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Safety Research :

 

0.8
2023CiteScore
 
22-é ïðîöåíòèëü
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Safety, Risk, Reliability and Quality:

 

0.8
2023CiteScore
 
19-é ïðîöåíòèëü
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Statistic, Probability and Uncertainty :

 

0.8
2023CiteScore
 
13-é ïðîöåíòèëü
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SCImago Journal & Country Rank

 

 

 

 

 

 

METHODOLOGY FOR PREDICTING DEPENDABILITY MEASURES OF SWARM STRUCTURES OF UNMANNED AERIAL VEHICLES OF AGRICULTURAL APPLICATION

35-53

 

 

A.A. Kostiuk, V.E. Tsvetkov, P.S. Korolev, S.N. Polesskiy

 

 

 

This paper presents a methodology for predicting dependability measures of swarm structures of unmanned aerial vehicles used in agriculture. The main attention is paid to the development of mathematical models for assessing the dependability of hardware, software, and communication systems in drone swarms. Two types of UAVs are considered in the paper: DJI Phantom 4 RTK (for crop monitoring) and Tevel Aerobotics (for automated harvesting). The developed methodology improves the accuracy of dependability prediction of UAV swarm structures, which helps to optimize their maintenance and increase the efficiency of their application in agriculture. The developed mathematical model for predicting the dependability of swarm structures of agricultural UAVs includes a combination of hardware and software components and communication systems. 

 

Cite:  A.A. Kostiuk, V.E. Tsvetkov, P.S. Korolev, S.N. Polesskiy METHODOLOGY FOR PREDICTING DEPENDABILITY MEASURES OF SWARM STRUCTURES OF UNMANNED AERIAL VEHICLES OF AGRICULTURAL APPLICATION. Reliability: Theory & Applications. 2025, September 3(86):  35-53, DOI: https://doi.org/10.24412/1932-2321-2025-386-35-53


 

 

 

A COMPARATIVE ANALYSIS OF POWER ISHITA DISTRIBUTION EXPLORING ITS SIGNIFICANT CONTRIBUTION AND PRACTICAL APPLICATIONS

54-66

 

 

Rashid A. Ganaie, Manzoor A. Khanday, Dilawar A. Bhat, Yudhishther Singh Bagal

 

 

 

This research presents the development of a novel statistical model termed the weighted power Ishita distribution. The study delves into its fundamental structural properties, offering a comprehensive theoretical foundation. The parameters of proposed distribution are meticulously estimated through the maximum likelihood estimation method, ensuring robust and reliable results. To validate its applicability and demonstrate its superiority, the model is evaluated using three real-world lifetime data sets, highlighting its efficacy and potential for practical applications.

 

Cite:  Rashid A. Ganaie, Manzoor A. Khanday, Dilawar A. Bhat, Yudhishther Singh Bagal A COMPARATIVE ANALYSIS OF POWER ISHITA DISTRIBUTION EXPLORING ITS SIGNIFICANT CONTRIBUTION AND PRACTICAL APPLICATIONS. Reliability: Theory & Applications. 2025, September 3(86):  54-66, DOI: https://doi.org/10.24412/1932-2321-2025-386-54-66


 

 

 

THE DEVELOPMENT OF RISK-BASED THINKING PRINCIPLES AT A MACHINE-BUILDING ENTERPRISE UNDER CONDITIONS OF INDUSTRY 4.0

67-77

 

 

Yaroslav Vavilin

 

 

 

The article deals with the problem of formal introduction of risk-based thinking features in machine-building production under conditions of Industry 4.0 together with the expansion of the use of digital technologies. The research aims to address the following objectives: to analyze the necessity and influence of risk management implementation within the organization's quality management system; to determine the levels required for realizing risk-based thinking; to develop a methodological foundation for integrating risk-based thinking considering Industry 4.0 elements; to perform a comparative analysis of the proposed model with known risk management systems. The study employs well-established methods of process-based approaches (Deming-Shewhart cycle) and systems analysis. The authors make an attempt to formalize the work on ensuring the proper use of risk and capability management tools from the perspective of a system analysis and process approach. Works related to risk management at the stages of the Deming-Shewhart cycle are highlighted and the levels and components of the machine-building production system model that are subject to analysis are determined. The task of introducing risk-based thinking in quality management systems of machine- building enterprises is critical due to the increasing complexity of products, increasing consumer demands and the need to ensure increased safety. Risk analysis makes it possible to identify potential threats to product quality in advance, minimize the consequences of defects, reduce error correction costs and increase the competitiveness of the enterprise in the market.

 

Cite:  Yaroslav Vavilin THE DEVELOPMENT OF RISK-BASED THINKING PRINCIPLES AT A MACHINE-BUILDING ENTERPRISE UNDER CONDITIONS OF INDUSTRY 4.0. Reliability: Theory & Applications. 2025, September 3(86):  67-77, DOI: https://doi.org/10.24412/1932-2321-2025-386-67-77


 

APPLICATION OF WEIGHT MEASURE ORDERING FOR INTUITIONISTIC FUZZY CRITICAL PATH ANALYSIS

78-89

 

 

S. Priyadharshini, G. Deepa, S. Ramprasath

 

 

 

The intuitionistic fuzzy critical path problem is a frequent and important challenge in network optimization, particularly in the planning and management of complex projects. However, the traditional critical path approach often fails to accurately reflect real-world scenarios. To address this, we have developed a critical path strategy within an intuitionistic fuzzy framework. In this study, the critical path is determined using a ranking algorithm, where the edge weights are modeled as triangular intuitionistic fuzzy numbers (ITFN). We have introduced definitions for ranking strategies that help identify the intuitionistic fuzzy critical path. Additionally, a proposed criticality degree measures that significance of each activity. Examples are provided to illustrate the proposed strategy, and the simulation results of the ranking techniques are also presented.

 

Cite:  S. Priyadharshini, G. Deepa, S. Ramprasath APPLICATION OF WEIGHT MEASURE ORDERING FOR INTUITIONISTIC FUZZY CRITICAL PATH ANALYSIS. Reliability: Theory & Applications. 2025, September 3(86):  78-89, DOI: https://doi.org/10.24412/1932-2321-2025-386-78-89


 

 

 

A RANKING FUNCTION APPROACH BASED ON CENTROID FOR GENERALIZED HEXAGONAL FUZZY NUMBERS TO SOLVE FUZZY MULTI-OBJECTIVE TRANSPORTATION PROBLEMS

90-106

 

 

Ramakant Sharma, Sohan Lal Tyagi

 

 

 

In a real-world scenario, the decision maker is unsure about the precise value of transportation parameters due to uncontrolled factors such as fuel prices, weather conditions, product availability, and requirements. Therefore, o fuzzy numbers are used to handle these uncertainties. This Paper aims to find an efficient solution to fuzzy multi-objective transportation problems (FMOTP) where all parameters (objective functions, availabilities, requirements) are given in the form of generalized hexagonal fuzzy numbers. In the Proposed approach, FMOTP is transformed into Fuzzy Single-Objective Transportation Problems (FSOTP) using the geometric mean technique. A new ranking function based on the centroid and in-center point method for hexagonal fuzzy numbers defuzzifies the FSOTP into a Crisp Single-Objective Transportation Problem (CSOTP). The optimal solution for the transformed CSOTP is obtained using the proposed approach based on the zero-entry cell method. Using the optimal solution of CSOTP the fuzzy efficient solution of FMOTP is obtained. Additionally, two numerical problems are solved to elaborate the Proposed approach, and results are compared with other existing methods. A comparison and analysis of the results show that the proposed approach provides a more optimized solution for FMOTP. This approach is easily applicable to real-life transportation problems in which decision-makers are unsure about the exact value of parameters. 

 

Cite:  Ramakant Sharma, Sohan Lal Tyagi A RANKING FUNCTION APPROACH BASED ON CENTROID FOR GENERALIZED HEXAGONAL FUZZY NUMBERS TO SOLVE FUZZY MULTI-OBJECTIVE TRANSPORTATION PROBLEMS. Reliability: Theory & Applications. 2025, September 3(86):  90-106, DOI: https://doi.org/10.24412/1932-2321-2025-386-90-106


 

 

 

A STATISTICAL FRAMEWORK FOR ENHANCING PROCESS CONTROL AND RELIABILITY USING AUTOENCODERS RANDOM SURVIVAL FORESTS AND NHPP MODELING

107-125

 

 

P. Sricharani, P. Satya Shekar Varma, M. V. Lavanya

 

 

 

Statistical Process Control (SPC) plays a critical role in ensuring the reliability and quality of high-grade products. This study introduces two advanced machine learning methods to enhance SPC by integrating Auto encoders for anomaly detection and Random Survival Forests (RSF) for failure prediction. The Autoencoder model is employed to monitor real-time sensor data, learning the normal patterns of product quality and identifying deviations that indicate potential quality issues. By flagging anomalies when product performance metrics diverge from expected thresholds, the autoencoder helps to adjust SPC limits dynamically, improving responsiveness to emerging quality concerns. Additionally, RSF is used to predict the likelihood of product failure over time, based on historical failure data and process parameters. This predictive approach enables proactive interventions to prevent quality issues before they occur, enhancing long-term product dependability. Together, these machine learning methods create a comprehensive framework for real-time monitoring and failure prediction, providing a more adaptive and data driven approach to quality control. The integration of Auto encoders and RSF into the SPC methodology significantly advances the precision and effectiveness of product reliability assessment, offering a powerful tool for maintaining high-quality standards in manufacturing processes. 

 

Cite:  P. Sricharani, P. Satya Shekar Varma, M. V. Lavanya A STATISTICAL FRAMEWORK FOR ENHANCING PROCESS CONTROL AND RELIABILITY USING AUTOENCODERS RANDOM SURVIVAL FORESTS AND NHPP MODELING. Reliability: Theory & Applications. 2025, September 3(86):  107-125, DOI: https://doi.org/10.24412/1932-2321-2025-386-107-125


 

 

 

A BAYESIAN APPROACH TO RELIABILITY ANALYSIS IN THE STRESS-STRENGTH MODEL WITH WEIGHTED EXPONENTIAL DISTRIBUTIONS CONSIDERING FUZZINESS

126-139

 

 

Alka Yadav, Satyanshu Kumar Upadhyay

 

 

 

The paper considers a Bayesian approach to the analysis of reliability in a stress-strength model when both stress and strength follow a weighted exponential distribution. The main focus of the paper considers a situation when the available data incorporate fuzziness. The situations when stress and strength distributions have common shape parameters and also when they have different shape and scale parameters are entertained separately. The entire analysis is done using the Bayes paradigm using weak proper priors for the model parameters. Since the resulting posteriors are not available in analytically closed form, the paper uses the recourse of Markov chain Monte Carlo simulation technique. Finally, a numerical illustration is provided based on real data examples. The results are found to be satisfactory.

 

Cite:  Alka Yadav, Satyanshu Kumar Upadhyay A BAYESIAN APPROACH TO RELIABILITY ANALYSIS IN THE STRESS-STRENGTH MODEL WITH WEIGHTED EXPONENTIAL DISTRIBUTIONS CONSIDERING FUZZINESS. Reliability: Theory & Applications. 2025, September 3(86):  126-139, DOI: https://doi.org/10.24412/1932-2321-2025-386-126-139


 

 

 

SYSTEMATIC FAILURES IN FUNCTIONAL SAFETY AND THE PROBABILITY MEASURE

140-148

 

 

Hendrik Schabe

 

 

 

In this paper the probability measure is discussed. The point of interest is, whether probabilistic models are stable under different conditions and if they can be used further on, when conditions change. Systematic failures, as described in many standards of functional safety, play a role regarding this problem. Reducing systematic failures also means, to keep probabilistic calculus working. However, systematic failures have not been studied systematically regarding the question to keep the probability measure. An outline is given on the connection between systematic failures and the possibility to use probability calculus in technical problems in exploitation situations, where data from e.g. lab experiments are extrapolated to use conditions. 

 

Cite:  Hendrik Schabe SYSTEMATIC FAILURES IN FUNCTIONAL SAFETY AND THE PROBABILITY MEASURE. Reliability: Theory & Applications. 2025, September 3(86):  140-148, DOI: https://doi.org/10.24412/1932-2321-2025-386-140-148


 

 

 

DEVELOPMENT OF A NEW CURRENT LIMITING SYSTEM WITH AUTOMATIC REGULATION OF CUT-OFF CURRENT

149-154

 

 

R.Z. Sultanov, N.A. Aliyev, G.A. Aliyeva

 

 

 

The article considers the problem of ensuring reliable operation of DC electric drives under short- term overloads, when the installed power of the electric motor is limited. It is shown that the use of traditional current cutoff units does not allow for the effective use of the maximum permissible overload capacity of the motor when changing the reference speed. The dependence of the permissible overload current on the rotation speed is analyzed, and the limitations of the existing control schemes are identified. In this paper, the existing schemes of automated electric drives equipped with traditional current cutoff units are considered and their main disadvantages are identified. As a solution, a current limiting system with automatic regulation of the cutoff current is proposed, aimed at increasing the reliability and energy efficiency of adjustable electric drives. The key feature of the proposed system is to adapt the cutoff current value depending on the rotation speed of the motor, which allows dynamically matching the electromechanical characteristics of the drive with the permissible overload curve of the motor. A current limiting circuit for a DC electric drive is proposed, in which the cutoff current setting is automatically changed depending on the value of the specified speed. The circuit ensures full use of the maximum permissible overload capacity of the electric motor at all values of the setting voltage. 

 

Cite:  R.Z. Sultanov, N.A. Aliyev, G.A. Aliyeva DEVELOPMENT OF A NEW CURRENT LIMITING SYSTEM WITH AUTOMATIC REGULATION OF CUT-OFF CURRENT. Reliability: Theory & Applications. 2025, September 3(86):  149-154, DOI: https://doi.org/10.24412/1932-2321-2025-386-149-154


 

A NEW MIN-MAX RANKED SET SAMPLING SCHEME WITH UNEQUAL SAMPLE SIZES

155-171

 

 

O. Rahimi Dehcheraghi, S.M.T.K. MirMostafaee

 

 

 

In this paper, a new type of ranked set sampling scheme with unequal sample sizes called the new min-max ranked set sampling scheme with unequal sample sizes, is proposed to expedite the sampling process and reduce costs by utilizing fewer data compared to the existing ranked set sampling plans with unequal sample sizes, such as the minimum ranked set sampling scheme with unequal samples. We study the parameter estimation for the exponential distribution using the maximum likelihood and Bayesian methods based on the new scheme. The Metropolis-Hastings strategy is implemented to derive the approximate Bayesian estimates of the parameter under two loss functions. A simulation study is conducted, from which the effectiveness of the new scheme can be observed compared to the simple random sampling scheme and the minimum ranked set sampling scheme with unequal samples. A real data set is also analyzed. Finally, The paper ends with some remarks.

 

Cite:  O. Rahimi Dehcheraghi, S.M.T.K. MirMostafaee A NEW MIN-MAX RANKED SET SAMPLING SCHEME WITH UNEQUAL SAMPLE SIZES. Reliability: Theory & Applications. 2025, September 3(86):  155-171, DOI: https://doi.org/10.24412/1932-2321-2025-386-155-171


 

 

 

ANALYSIS OF MAPj, PH°/PH[, PH°/1 RETRIAL INVENTORY QUEUE, TWO WAY COMMUNICATION, (S, S) REPLENISHMENT POLICY, NEGATIVE ARRIVAL, WORKING BREAKDOWN AND REPAIR

172-186

 

 

G. Ayyappan, V. Ganesan

 

 

 

The retrial inventory queueing model with two-way communication, the (s, S) replenishment strategy, negative arrival, working breakdown, and repair are all topics that are discussed in this paper. Our assumption is that the arrival is a Markovian arrival process and that a server is the entity that is responsible for providing phase type services. When there is a positive inventory and the server is idle, the customer who arrives is instantly attended to their needs. In the event that this instance does not occur, the customer who is arriving will be moved to orbit, and a retrial customer from orbit will join afterwards if the server is idle and has positive inventory. When the inventory level is positive, the server will make outgoing calls that follow phase type distribution during the idle period. If the inventory level is zero, the server will continue to stay idle. A negative arrival may occur while the server is providing service. Since the server is experiencing a breakdown, the consumer will experience slow service at this time. After the slow service ends, the server will immediately begin the repair procedure, which follows a phase-type distribution. The policy of (s,S) is utilised to replenish the items. By employing the matrix analytic method, we are able to derive the steady state probability vector. Additionally, we address the busy period, performance measurements, and cost analysis, in addition to providing some numerical examples.

 

Cite:  G. Ayyappan, V. Ganesan ANALYSIS OF MAPj, PH°/PH[, PH°/1 RETRIAL INVENTORY QUEUE, TWO WAY COMMUNICATION, (S, S) REPLENISHMENT POLICY, NEGATIVE ARRIVAL, WORKING BREAKDOWN AND REPAIR. Reliability: Theory & Applications. 2025, September 3(86):  172-186, DOI: https://doi.org/10.24412/1932-2321-2025-386-172-186


 

 

 

GROK'S ROLE IN TRANSFORMING COMMUNICATION FOR DISASTER RISK MANAGEMENT

187-191

 

 

Renat R. Khaydarov

 

 

 

The increasing prevalence of natural hazards, exacerbated by climate change and urbanization, underscores the urgency of effective disaster risk management (DRM) to safeguard communities and infrastructure. Technical assessments, laden with specialized terminology, often hinder stakeholder engagement, particularly among non-specialists critical to decision-making processes. This study explores the prospective applications of Grok, an AI model by xAI, in enhancing DRM through its advanced natural language processing capabilities. Grok can translate complex multi-hazard risk evaluations, develop tailored educational content, and support real-time early warning systems, fostering inclusive communication. The research aims to evaluate Grok's efficacy in bridging technical and non-technical domains, promoting informed urban planning and disaster preparedness. Ultimately, this research lays the groundwork for future empirical studies on Al-driven DRM innovations. 

 

Cite:  Renat R. Khaydarov GROK'S ROLE IN TRANSFORMING COMMUNICATION FOR DISASTER RISK MANAGEMENT. Reliability: Theory & Applications. 2025, September 3(86):  187-191, DOI: https://doi.org/10.24412/1932-2321-2025-386-187-191


 

 

 

METHODOLOGY FOR DETERMINING TYPICAL SCENARIOS OF TOTAL ELECTRICITY GENERATION BY GREEN SOURCES REDUCING THE RISK OF DISRUPTION OF BALANCE RELIABILITY

192-205

 

 

Rahmanov Nariman Rahman, Guliyev Huseyngulu Bayram, Ibrahimov Famil Shamil

 

 

 

The article proposes a methodology for identifying scenarios for aggregate electricity generation by renewable sources, such as wind and solar power plants, located in geographically diverse regions of the area with different climatic and weather conditions. To cover the demand of electric power systems, it is rational to use these green sources with complementarity from generation when planning load modes, as well as to reduce the risk of balance reliability of power systems. To determine the scenarios of aggregate generation of the used green sources, a cluster analysis is used based on the clustering of medoids using real-time measurements of wind speed, solar radiation and ambient temperature performed for all regions of the considered area where all green sources of electricity in the form of wind and solar power plants are installed. Clusters of these sources and loads are established separately and jointly. For each scenario of generation and planned growth in demand of the power system, the volume of additional capacity of green sources is estimated. The proposed methodology was tested on the example of the power system of Azerbaijan. The study found that, in order to reduce the risk of disruption to the system's balance reliability, scenarios of combined generation from wind farms located in the northern regions adjacent to the Caspian Sea with electricity generation from solar farms located in the southwestern regions of the country provide a more reliable way to increase the share of wind and solar generation in covering the planned demand growth compared to scenarios based on the separate use of these green energy sources. 

 

Cite:  Rahmanov Nariman Rahman, Guliyev Huseyngulu Bayram, Ibrahimov Famil Shamil METHODOLOGY FOR DETERMINING TYPICAL SCENARIOS OF TOTAL ELECTRICITY GENERATION BY GREEN SOURCES REDUCING THE RISK OF DISRUPTION OF BALANCE RELIABILITY. Reliability: Theory & Applications. 2025, September 3(86):  192-205, DOI: https://doi.org/10.24412/1932-2321-2025-386-192-205


 

 

 

REDUCING RENTAL COSTS IN TWO-STAGE HYBRID FSSP: BRANCH AND BOUND VS. HEURISTIC APPROACHES

206-216

 

 

Kanika Gupta, Deepak Gupta, Sonia Goel

 

 

 

This paper proposes a Branch and Bound (BB) based heuristic to solve a two-stage hybrid Flow Shop Scheduling Problem (HFSSP), incorporating practical constraints such as machine rental costs, transportation time, and job weightage. The scheduling environment includes multiple parallel machines at the first stage, where each job can be processed on any one machine, followed by a single rented machine at the second stage. To effectively model uncertainty in processing times, triangular fuzzy numbers are used. Additionally, transportation time between stages and job weightage are integrated into the model to reflect realistic industrial conditions. The proposed BB algorithm systematically explores the space of feasible job sequences, pruning non-promising branches to derive an optimal or near-optimal schedule under the given constraints. Its performance is benchmarked against two widely used heuristic approaches—NEH and GRASP-NEH—focusing on minimizing total elapsed time and rental cost of the second-stage machine. Experimental results indicate that the BB approach consistently outperforms the heuristic methods, particularly in reducing rental costs and providing better control over the utilization of the rented resource. While heuristic methods offer computational speed, they often compromise on cost efficiency and precision in handling fuzzy parameters. Overall, the study demonstrates the effectiveness of the BB method as a robust and efficient alternative for solving complex scheduling problems, especially in scenarios where minimizing rental costs is a critical objective. The integration of fuzzy processing times, transportation delays, and job priorities further enhances the practical relevance of the proposed approach.

 

Cite:  Kanika Gupta, Deepak Gupta, Sonia Goel REDUCING RENTAL COSTS IN TWO-STAGE HYBRID FSSP: BRANCH AND BOUND VS. HEURISTIC APPROACHES. Reliability: Theory & Applications. 2025, September 3(86):  206-216, DOI: https://doi.org/10.24412/1932-2321-2025-386-206-216


 

ON THE BURR TYPE IV DISTRIBUTION APPLIED TO LIFETIME SURVIVAL DATA

217-228

 

 

Claire Joy G. Mariquit, Bernadette F. Tubo

 

 

 

This study presents the Burr type IV (Burrjy) distribution, which is one of the twelve continuous distributions within the Burr family. The paper thoroughly evaluates its properties and applications in survival analysis. Key distributional characteristics such as survival, hazard, quantile, cumulative distribution, and probability density functions are derived. Density plots are simulated to illustrate common patterns, including J-shaped, U-shaped, and reversed J-shaped forms, frequently observed in engineering and reliability contexts. The applicability of the Burrjy distribution is demonstrated through three real-life datasets, each exhibiting distinct density shapes. The findings affirm the flexibility and robustness of the Burrjy distribution in modeling a variety of data shapes, underscoring its potential for broader applications in survival analysis and related fields. 

 

Cite:  Claire Joy G. Mariquit, Bernadette F. Tubo ON THE BURR TYPE IV DISTRIBUTION APPLIED TO LIFETIME SURVIVAL DATA. Reliability: Theory & Applications. 2025, September 3(86):  217-228, DOI: https://doi.org/10.24412/1932-2321-2025-386-217-228


 

 

 

A NON- MARKOVIAN RETRIAL QUEUE WITH NON PERSISTENT CUSTOMERS, GENERAL RETRIAL TIMES ALONG WITH REOCCURRING CUSTOMERS

229-237

 

 

S. Palaniammal, K. Kumar, R.Keerthana

 

 

 

A non-Markovian retrial queue with non persistent customers, general retrial times along with reoccurring customers is taken into concern in this place study. In this model, the retrial periods for reoccurring customers have an exponential distribution, while all the service periods and retrial periods for transitory customers are pretended to follow a general distribution. The PGF for the total amount of customers and the average amount of customers in the invisible waiting region is acquired by applying the supple-mentary variable method. We compute the waiting period delivery. Out of attention, special cases are conferred. Numerical outcomes are reveals.

 

Cite:  S. Palaniammal, K. Kumar, R.Keerthana A NON- MARKOVIAN RETRIAL QUEUE WITH NON PERSISTENT CUSTOMERS, GENERAL RETRIAL TIMES ALONG WITH REOCCURRING CUSTOMERS. Reliability: Theory & Applications. 2025, September 3(86):  229-237, DOI: https://doi.org/10.24412/1932-2321-2025-386-229-237


 

 

 

RELIABILITY OF ELECTRICAL MACHINES VIA POWER LOSS MODELING IN MATLAB

238-248

 

 

Sara Alimamedova, Saida Kerimova

 

 

 

The article discusses a reliable mathematical approach to calculating power losses in electrical equipment, which is a critical component in the design, analysis, and optimization of electric power systems. Ensuring accurate loss estimation requires detailed modeling of equipment parameters such as rated power, voltage, current, resistance, and material properties that influence energy dissipation. For alternating current systems, it is particularly important to consider the interaction of active and reactive components, as well as the losses occurring in conductors, magnetic circuits, and other elements. The application of proven mathematical models enables engineers to evaluate system efficiency and operational stability under different scenarios. MATLAB tools and algorithms play a key role in automating these calculations, allowing for precise simulations across a wide range of load conditions, voltage levels, and equipment configurations. This not only improves the accuracy of loss assessments but also supports optimization of design parameters to ensure long-term reliability, energy efficiency, and cost-effectiveness of electrical machines and systems.

 

Cite:  Sara Alimamedova, Saida Kerimova RELIABILITY OF ELECTRICAL MACHINES VIA POWER LOSS MODELING IN MATLAB. Reliability: Theory & Applications. 2025, September 3(86):  238-248, DOI: https://doi.org/10.24412/1932-2321-2025-386-238-248


 

 

 

RELIABILITY ANALYSIS AND PERFORMANCE OPTIMIZATION OF A 2-OUT-OF-4 REDUNDANT SYSTEM USING RPGT AND METAHEURISTIC ALGORITHMS

249-256

 

 

Shakuntla Singla, Shilpa Rani, Diksha Mangla

 

 

 

In this paper focuses on the reliability analysis and performance optimization of a 2-out-of-4 redundant system, modeled using the Regenerative Point Graphical Technique (RPGT). The study aims to evaluate system behavior under various failure and repair rate conditions and to determine optimal parameters that enhance system reliability and availability. The system consists of four units A, B, C, and D arranged in a 2-out-of-4 configuration, meaning the system continues to function as long as at least two units are operational. A state-space model is developed, where each state corresponds to a distinct combination of operational, failed, and repair conditions of these units. The transitions between these states are governed by exponentially distributed failure and repair processes, and are represented using a directed graph structure. Transition probabilities are derived from these time-dependent exponential distributions, allowing precise evaluation of system behavior. To enhance the system's performance, three metaheuristic optimization algorithms — Cuckoo Search Algorithm (CSA), Particle Swarm Optimization (PSO), and Genetic Algorithm (GA)-are employed. These algorithms are applied to optimize key system parameters: failure rates (A) and repair rates (p). The objective is to maximize the Mean Time to System Failure (MTSF) and steady-state availability, and to minimize the expected number of inspections required by the repair personnel. The comparative analysis of optimization results reveals the relative effectiveness of each algorithm. PSO consistently provides the highest values for MTSF and availability, indicating stronger performance in identifying optimal solutions. CSA also performs well, showing close results to PSO. GA, while effective, yields comparatively lower reliability indices. The outcomes demonstrate how advanced optimization techniques can be successfully integrated with RPGT-based modeling to develop a detailed and practical understanding of complex redundant systems. These insights support better maintenance planning, enabling organizations to improve reliability and reduce downtime in industrial, communication, and critical control systems. This methodology can be extended to other system configurations and industries, making it a valuable tool in the field of reliability engineering and operational research

 

Cite:  Shakuntla Singla, Shilpa Rani, Diksha Mangla RELIABILITY ANALYSIS AND PERFORMANCE OPTIMIZATION OF A 2-OUT-OF-4 REDUNDANT SYSTEM USING RPGT AND METAHEURISTIC ALGORITHMS. Reliability: Theory & Applications. 2025, September 3(86):  249-256, DOI: https://doi.org/10.24412/1932-2321-2025-386-249-256


 

 

 

CENSORED COUNT DATA REGRESSION MODELS: NUMBER OF CAESAREAN SECTION DELIVERIES USING INTEGRATED NESTED LAPLACE APPROXIMATION

257-269

 

 

Srinu Setti, B. Muniswamy

 

 

 

Count data depicts the frequency of an occurrence within a specific time frame. Consider the frequency of caesarean operations that women undergo during their lives. Almost every academic field, including management, economics, medicine, and industrial organizations, relies on count data. Count data is extensively utilized across various fields, including marketing, public health, and biomedical science. This study aims to estimate the posterior means, variances, or quantiles of the NCSD for women aged 15 to 49 in Andhra Pradesh, India, using the RCPRM and RCNBRM methodologies. The RCPRM and RCNBRM are used to determine the optimal fit. The secondary dataset NFHS-5 is used for the study. This research utilizes INLA to model the NCSD. Subsequently, it analyzed delivery patterns among pregnant women. Information criteria DIC and WAIC are utilized to compare for the best fit. The DIC values 4608.60 and 4593.90 of RCNBRM are less than the DIC values 4864.74 and 4860.68 of RCPRM. Thus, from the results, it is inferred that RCNBRM is the best fit for NCSD and that Breech Presentation, the present age of the respondent, High Blood Pressure, Child is Twin, Prolonged Labour, Education Level, and Heart Disease are significant determinants of the NCSD. Therefore, government policymakers need to consider these variables while making healthcare policies for women aged 15 to 49 years who are of childbearing age.

 

Cite:  Srinu Setti, B. Muniswamy CENSORED COUNT DATA REGRESSION MODELS: NUMBER OF CAESAREAN SECTION DELIVERIES USING INTEGRATED NESTED LAPLACE APPROXIMATION. Reliability: Theory & Applications. 2025, September 3(86):  257-269, DOI: https://doi.org/10.24412/1932-2321-2025-386-257-269


 

 

 

FIXED POINT THEOREMS IN TRICOMPLEX VALUED CONTROLLED METRIC SPACES

270-278

 

 

Shivani Chourasiya, Kavita Shrivastava

 

 

 

Throughout the years, scholars have broadened traditional fixed point theories to include more intricate structures like tricomplex valued metric spaces, aiming to tackle issues in multidimensional and hyper-complex contexts. While there is a rising interest in tricomplex valued spaces, the current literature addressing fixed point theorems in these areas presents several limitations. The existing research highlights numerous shortcomings; thus, this article employs innovative types of contraction mappings via a control function to illustrate fixed point theorems in tricomplex valued controlled metric spaces. These findings enhance the understanding of fixed point theory and pave the way for new applications in more complex and diverse mathematical frameworks. Consequently, our study fosters progress in the field, establishing a strong basis for future research and potential uses across various scientific and engineering fields. 

 

Cite:  Shivani Chourasiya, Kavita Shrivastava FIXED POINT THEOREMS IN TRICOMPLEX VALUED CONTROLLED METRIC SPACES. Reliability: Theory & Applications. 2025, September 3(86):  270-278, DOI: https://doi.org/10.24412/1932-2321-2025-386-270-278


 

 

 

BAYESIAN ESTIMATION OF POISSON-COMPOUNDED EXPONENTIAL TYPE DISTRIBUTION UNDER DIFFERENT LOSS FUNCTIONS

279-288

 

 

Na Elah, Peer Bilal Ahmad

 

 

 

Poisson moment exponential distribution is an important distribution and has gained special attention recently. It plays role in various fields, mostly in actuarial sciences. Thus its parametric estimation becomes important thing to do. The classical approach using the maximum likelihood method is the most used way to estimate the parameters of a distribution. In this paper, we considered the Bayesian approach to estimate the parameter of the distribution using beta prior which is a conjugate prior. The Bayes estimate for the parameter is obtained under Squared Error Loss Function (SELF) which is a symmetric loss function, Weighted SELF (WSELF) and Entropy Loss Function (ELF). Through a simulation study, the comparison is made on the performance of Bayes estimate under these loss functions with respect to Bias and Mean Square Error (MSE).

 

Cite:  Na Elah, Peer Bilal Ahmad BAYESIAN ESTIMATION OF POISSON-COMPOUNDED EXPONENTIAL TYPE DISTRIBUTION UNDER DIFFERENT LOSS FUNCTIONS. Reliability: Theory & Applications. 2025, September 3(86):  279-288, DOI: https://doi.org/10.24412/1932-2321-2025-386-279-288


 

 

 

OPTIMIZING FUZZY DETERIORATING INVENTORY MODEL WITH TIME DEPENDENT DEMAND AND PARTIAL BACKLOGGING UNDER RESALABLE RETURNS

289-299

 

 

Kapil Dave, Tanuj Kumar

 

 

 

This paper investigates with the development of a fuzzy inventory model with timevarying demand, deterioration and backlogging with resalable returns. The returns rate, demand and backlogging parameters are taken as trapezoidal fuzzy numbers. Numerical example is given to validate the proposed mathematical model which has been developed for determining the optimal cycle time and optimal total inventory cost and profit. Sensitivity analysis is also carried out to explore the effect of changes in the optimal solution with respect to change in various parameters. The aim of this paper is to develop inventory policies that minimize the total cost so that to get the maximum total profit in both crisp and fuzzy modeling, and comparison of crisp and fuzzy models. Our study focuses on de-fuzzifying the total cost using the signed distance method and comparing it with the crisp model. This inventory model incorporates fuzzy demand and constant holding cost per unit item under the reasonable return policy while considering the impact of deterioration as a linearly increasing function of time. The retailer allows its unsatisfactory costumers to return their products. We assume that the return product will be sold at the same price. Customers are allowed to return the product during any phase of the length of the replenishment cycle. The retailer does not return the full amount to its customers for the returned goods. He offers 80% of the initial amount of the product. The number of returns are assumed to be proportional to demand. The demand is dependent on time. Partial backlogging is an important issue in the inventory theory which is related how to deal with the unfulfilled demand that occurs due to the shortage of stock. In real practice some customers prefers to wait for backorder during the shortage time and some turns to buy from other sellers. The waiting time period for next replenishment determine whether the backlogging would be accepted or not. During the shortage period the longer the waiting time is, the smaller is the backlogging rate would be. So backlogging rate is a variable that depends on the waiting time for next replenishment.

 

Cite:  Kapil Dave, Tanuj Kumar OPTIMIZING FUZZY DETERIORATING INVENTORY MODEL WITH TIME DEPENDENT DEMAND AND PARTIAL BACKLOGGING UNDER RESALABLE RETURNS. Reliability: Theory & Applications. 2025, September 3(86):  289-299, DOI: https://doi.org/10.24412/1932-2321-2025-386-289-299


 

 

 

A COMPARATIVE ANALYSIS OF RESPONSE SURFACE METHODOLOGY IN LINEAR PROGRAMMING

300-309

 

 

Mushtaq A. Lone, S. A. Mir, R. Vijaykrishnaraj, Showkat Ahmad Bhat, Aafaq A. Rather, Raeesa Bashir, Manzoor A. Khanday, Aamir Majeed Parray

 

 

 

A linear mathematical programming approach has been employed to tackle the problem of land allocation in this comparative study. One design of experiment technique used in creating new processes and improving their efficiency is response surface approach. Different search methods have been employed in this study to identify the best distribution of agricultural land. The results of all formulated mathematical programming problem are obtained by using R software and different R functions like mexchalgorithmO and qconalgorithm (), argumants to these problems are bl, b2, b3 were developed. Furthermore, the Branch and Bound method has been utilized to provide the proper integer solution when the problem's solution turns out to be non-integer.

 

Cite:  Mushtaq A. Lone, S. A. Mir, R. Vijaykrishnaraj, Showkat Ahmad Bhat, Aafaq A. Rather, Raeesa Bashir, Manzoor A. Khanday, Aamir Majeed Parray A COMPARATIVE ANALYSIS OF RESPONSE SURFACE METHODOLOGY IN LINEAR PROGRAMMING. Reliability: Theory & Applications. 2025, September 3(86):  300-309, DOI: https://doi.org/10.24412/1932-2321-2025-386-300-309


 

 

 

REGRESSION WITH VOLATILE ERRORS IN THE PRESENCE OF MEASUREMENT ERRORS

310-321

 

 

Anna Thomas, Nimitha John

 

 

 

This study explores the estimation and testing of regression models with volatile errors when measurement errors are present. The presence of measurement error in models with heteroscedastic disturbances, such as those following an autoregressive conditional heteroscedasticity (ARCH) or Generalized ARCH (GARCH) structure, can lead to biased estimates and misleading inferences. To address this, we develop an estimation framework that accounts for both heteroscedasticity and mismeasured observations, ensuring consistent and asymptotically normal parameter estimates. We estimate the parameters using corrected score estimation and weighted linear regression, which effectively mitigate the impact of measurement error and hetroscedasticity. Additionally, we perform a Likelihood Ratio (LR) test to assess the significance of measurement errors in regression models with volatile errors. Through Monte Carlo simulations, we analyze the bias and efficiency of traditional estimators and demonstrate the robustness of our proposed approach. Finally, the methodology is applied to real-life economic and financial data, illustrating its practical relevance and effectiveness in empirical research. The findings contribute to improving statistical inference in models where measurement error and volatility coexist, ensuring more reliable and accurate parameter estimation. 

 

Cite:  Anna Thomas, Nimitha John REGRESSION WITH VOLATILE ERRORS IN THE PRESENCE OF MEASUREMENT ERRORS. Reliability: Theory & Applications. 2025, September 3(86):  310-321, DOI: https://doi.org/10.24412/1932-2321-2025-386-310-321


 

 

 

RISK-BASED THINKING AND MEASUREMENT UNCERTAINTY: ADDRESSING ISO/IEC 17025 CHALLENGES WITH MODERN TOOLS

322-329

 

 

Rashid Mammadov

 

 

 

ISO/IEC 17025, the internationally recognized standard for the competence of testing and calibration laboratories, fundamentally embeds risk-based thinking (RBT) as a cornerstone for achieving and maintaining the reliability of measurement results and the robust management of measurement uncertainty. This article critically examines the synergistic application of RBT to proactively address the inherent and often complex challenges associated with quantifying and controlling measurement uncertainty. It aims to provide laboratories with practical, actionable insights into leveraging modern tools and methodologies that are not only compliant with ISO/IEC 17025 requirements but also enhance operational effectiveness. By exploring a spectrum of advanced statistical techniques (such as Monte Carlo simulations and Bayesian approaches), the integration of sophisticated digital tools (including TIMS, specialized uncertainty software, and data analytics), and the adoption of innovative operational practices, this study delineates a clear roadmap. The ultimate goal is to empower laboratories to bolster confidence in their measurement outcomes, ensure unimpeachable metrological traceability, stringently adhere to regulatory and customer compliance, and foster a culture of continuous improvement in their quality management systems.

 

Cite:  Rashid Mammadov RISK-BASED THINKING AND MEASUREMENT UNCERTAINTY: ADDRESSING ISO/IEC 17025 CHALLENGES WITH MODERN TOOLS. Reliability: Theory & Applications. 2025, September 3(86):  322-329, DOI: https://doi.org/10.24412/1932-2321-2025-386-322-329


 

 

 

AN INTEGRATED APPROACH TO ENSURING THE RELIABILITY OF POWER TRANSMISSION LINES IN THE CONTEXT OF DIGITAL ENERGY

330-338

 

 

I.N. Rahimli, N.A. Ganiyeva

 

 

 

In the context of the rapid development of digital technologies and their large-scale implementation in various sectors of the economy, the energy industry is also entering a phase of deep digital transformation. One of the key areas of this transformation is increasing the reliability and manageability of the energy infrastructure, in particular, power transmission lines (PTL), which are the main element of the electricity transmission and distribution system. Modern challenges, such as the increasing load on the power grid, changing climate conditions and the need to integrate distributed energy sources, require new approaches to reliability management. This paper discusses the key elements of digital transformation, including the use of intelligent monitoring systems, the Internet of Things (IoT), big data analysis and artificial intelligence for diagnostics and forecasting the technical condition of power transmission lines. The need for a comprehensive strategy combining technical, organizational and information measures is substantiated. Recommendations are presented for the implementation of digital solutions in the practice of operating power lines in order to increase their fault tolerance, prompt response to incidents and the overall efficiency of the power system.

 

Cite:  I.N. Rahimli, N.A. Ganiyeva AN INTEGRATED APPROACH TO ENSURING THE RELIABILITY OF POWER TRANSMISSION LINES IN THE CONTEXT OF DIGITAL ENERGY. Reliability: Theory & Applications. 2025, September 3(86):  330-338, DOI: https://doi.org/10.24412/1932-2321-2025-386-330-338


 

 

 

IMPROVING THE RELIABILITY OF DISTRICT HEATING SYSTEMS AT CHP PLANTS UNDER VARIABLE THERMAL LOADS

339-344

 

 

G.K. Abdullayeva, R.K. Karimova, A.L. Bakhtiyarov

 

 

 

District heating systems powered by Combined Heat and Power (CHP) plants are critical for delivering thermal energy to residential, industrial, and municipal consumers. However, the variability of thermal load—driven by daily and seasonal demand fluctuations—poses significant challenges to system reliability. This paper presents a methodology for evaluating the reliability of such systems under dynamic thermal conditions. By combining deterministic modeling of thermal load profiles with a stochastic failure analysis of key components, the study performs a year-long simulation with hourly resolution. A time-dependent failure rate model is introduced, correlating failure intensity with the rate of change in thermal demand, thereby accounting for the mechanical and thermal stress experienced by pumps, valves, pipelines, and heat exchangers. Simulation results reveal that while modern CHP equipment has high baseline reliability, rapid thermal load transitions notably increase the likelihood of failures. These findings highlight the necessity of predictive maintenance strategies and adaptive control mechanisms. The proposed framework contributes to the development of resilient and smart district heating infrastructures capable of sustaining reliable operation under increasingly complex load dynamics.

 

Cite:  G.K. Abdullayeva, R.K. Karimova, A.L. Bakhtiyarov IMPROVING THE RELIABILITY OF DISTRICT HEATING SYSTEMS AT CHP PLANTS UNDER VARIABLE THERMAL LOADS. Reliability: Theory & Applications. 2025, September 3(86):  330-338, DOI: https://doi.org/10.24412/1932-2321-2025-386-339-344 


 

 

 

AN INTEGRATED APPROACH TO ENHANCING THE RELIABILITY OF SUBSTATION POWER SUPPLY SYSTEMS

345-353

 

 

Rahila Muradova

 

 

 

The reliability of substation power supply systems is a critical factor in ensuring the stability and uninterrupted operation of modern power grids. This paper examines advanced quantitative failure analysis methods that incorporate physical degradation processes, component interdependencies, and time-dependent failure characteristics. An integrated approach is proposed, combining structural redundancy, digital condition monitoring, thermal management, and predictive maintenance strategies. Modeling and statistical analysis confirm that implementing these comprehensive measures can increase system availability to 0.999 and reduce failure rates by 25- 40%. The methodology is applicable to both new substation designs and upgrades of existing infrastructure, supporting improved technical reliability and economic efficiency in operation. 

 

Cite:  Rahila Muradova AN INTEGRATED APPROACH TO ENHANCING THE RELIABILITY OF SUBSTATION POWER SUPPLY SYSTEMS. Reliability: Theory & Applications. 2025, September 3(86):  345-353, DOI: https://doi.org/10.24412/1932-2321-2025-386-345-353


 

 

 

KRISHNAV-P DISTRIBUTION AND ITS BIOMEDICAL APPLICATION

354-366

 

 

Praseeja C. B., Prasanth C. B.

 

 

 

This paper introduces a novel class of distributions, termed the KrishNav-P distribution (KNPD), developed through the application of a weighted distribution technique to the baseline Fav-Jerry distribution. The statistical properties of the KNPD are rigorously analyzed, and parameter estimation is performed using the maximum likelihood estimation method. To evaluate the practical applicability and performance of the proposed distribution, it is applied to a real-world dataset consisting of weight loss measurements (in kilograms) from 77 secondary school students aged 12 to 15 in the Thrissur District, Kerala. The data, collected between January and June 2021, pertain to students who experienced weight loss following a COVID-19 infection and tested the goodness of fit and the superiority of the distribution over the baseline and other existing distributions are also demonstrated. 

 

Cite:  Praseeja C. B., Prasanth C. B. KRISHNAV-P DISTRIBUTION AND ITS BIOMEDICAL APPLICATION. Reliability: Theory & Applications. 2025, September 3(86):  354-366, DOI: https://doi.org/10.24412/1932-2321-2025-386-354-366


 

 

 

OPTIMIZING PATHFINDING: A NOVEL ALGORITHM FOR GRAPH THEORY

367-380

 

 

Aijaz Ahmad Magray, Ajjaz Maqbool Dar, Firdous Ahmad, Aafaq A. Rather, R. Vijaykrishnaraj, D. Vedavathi Saraja, Syed M. Parveen, Raeesa Bashir

 

 

 

In this paper, a new proposed algorithm called the Pentacode-algorithm is successfully designed and implemented to solve the space and time problems associated with previous algorithms. Several parameters, such as Shortest Distance (SD), Time to Search Shortest Distance (TSSD), and Loss of Information Packets (LIP) have been checked and verified using the proposed algorithm. The simulation results achieved from the MATLAB tool authenticate the correct functionality of the proposed Pentacode-algorithm. Advance improvements have been proved in the proposed algorithm in terms of the space search and time issues. In addition, First-Node-Die (FND), Half-Node-Die (HND) and Last- Node-Die (LND) are determined in our results. The comparative results have shown that the Pentacode-algorithm is more proficient than the previous algorithm. This Pentacode-algorithm can be applied to warless communication systems, network routing and protocol multidirectional transmission and Quantum computing research. 

 

Cite:  Aijaz Ahmad Magray, Ajjaz Maqbool Dar, Firdous Ahmad, Aafaq A. Rather, R. Vijaykrishnaraj, D. Vedavathi Saraja, Syed M. Parveen, Raeesa Bashir OPTIMIZING PATHFINDING: A NOVEL ALGORITHM FOR GRAPH THEORY. Reliability: Theory & Applications. 2025, September 3(86):  367-380, DOI: https://doi.org/10.24412/1932-2321-2025-386-367-380


 

 

 

ANALYSING STRESS STRENGTH RELIABILITY OF LIFE TEST ON AEROSOL PARTICLES BY GOMPERTZ DISTRIBUTION USING NOVEL JOINT PROGRESSIVE CENSORING

381-389

 

 

Showkat Ahmad Lone

 

 

 

System reliability has become a popular subject of study in engineering due to its wide range of potential applications. When a reliability practitioner aims to observe a specific number of failed units, a balanced case of joint progressive censoring scheme is proposed to improve the efficiency of an experiment. This paper investigates parametric inference for system reliability using a novel case of joint progressive censoring, with a specific focus on two independent Gompertz populations. The system reliability parameter is estimated using both likelihood and Bayesian inferential approaches. The Metropolis-Hastings algorithm is employed to compute Bayesian estimates under different loss functions. Asymptotic confidence intervals and Bayesian credible intervals are also derived. A thorough simulation study is conducted to evaluate the performance of the proposed methods across various sample sizes. Additionally, to demonstrate the practical utility of the approach, virus-containing aerosol particles (VCAP) lifetime data under two velocities are analyzed. 

 

Cite:  Showkat Ahmad Lone ANALYSING STRESS STRENGTH RELIABILITY OF LIFE TEST ON AEROSOL PARTICLES BY GOMPERTZ DISTRIBUTION USING NOVEL JOINT PROGRESSIVE CENSORING. Reliability: Theory & Applications. 2025, September 3(86):  381-389, DOI: https://doi.org/10.24412/1932-2321-2025-386-381-389


 

 

 

A NEW COUNT DATA PROBABILITY MODEL: PROPERTIES AND APPLICATIONS

390-405

 

 

Morifat, Bilal Ahmad Para

 

 

 

In the field of count data analysis, over-dispersion poses significant challenges, often limiting the effectiveness of traditional Poisson model. To address this limitation, we propose a novel two parameter distribution as an extension of Poisson distribution namely two-Parameter Poisson Garima Distribution (TPPGD). This distribution enhances modeling flexibility for over-dispersed data, offering a superior fit for real-world datasets. In this paper we derive the theoretical properties of TPPGD, including its probability mass function, cumulative distribution function and different statistical properties. Parameter estimation has been done using the maximum likelihood method and the moment method. Finally, the validity of the proposed model is checked using different real world data sets. 

 

Cite:  Morifat, Bilal Ahmad Para A NEW COUNT DATA PROBABILITY MODEL: PROPERTIES AND APPLICATIONS. Reliability: Theory & Applications. 2025, September 3(86):  390-405, DOI: https://doi.org/10.24412/1932-2321-2025-386-390-405


 

 

 

RELIABILITY, AVAILABILITY AND MAINTAINABILITY (RAM) ANALYSIS OF SOME PROCESS INDUSTRIES: A CRITICAL REVIEW OF LITERATURE

406-421

 

 

Punam Rani, Sangeeta Malik, Arun Kumar

 

 

 

This paper reviews the literature on reliability, availability, and maintainability analysis of process industrial systems. In today's automated world, it is unfeasible to live exclusive of reliable systems, so every one of the working engineering system be anticipated to remain operational with maximum effectiveness for the longest period of time, or reliable operation. Throughout the years, the primary goal has been to concentrate on the system presentation in excess of an extended period of time; in essence, these are case studies on the system concert of industrial systems. While achieving 100% failure-free operation in production is not practicable, industrial systems that can be repaired can have their system failures minimized. In this paper, an effort has been made to compile the necessary literature and offer some helpful advice on how to broaden the field for more beneficial outcomes on system performance.

 

Cite:  Punam Rani, Sangeeta Malik, Arun Kumar RELIABILITY, AVAILABILITY AND MAINTAINABILITY (RAM) ANALYSIS OF SOME PROCESS INDUSTRIES: A CRITICAL REVIEW OF LITERATURE. Reliability: Theory & Applications. 2025, September 3(86):  406-421, DOI: https://doi.org/10.24412/1932-2321-2025-386-406-421


 

 

 

ANALYSIS OF JOINT MULTIPLY TYPE-II CENSORED DATA USING THE GIBBS SAMPLER ALGORITHM 

422-434

 

 

Vishal Singh, Akanksha Gupta and S. K. Upadhyay

 

 

 

This paper introduces a systematic approach for analyzing data under joint multiply type-II censoring. The study assumes a one-parameter exponential lifetime distribution and focuses on estimating unknown parameters. The maximum likelihood method is used to obtain frequentist point estimates, while a Bayesian framework is adopted to draw the corresponding Bayes inferences. To effectively handle censored data, an extended Gibbs sampler algorithm is employed, treating the unknown observations as further unknowns and estimating them accordingly. This methodology ensures a comprehensive and robust inference process by simultaneously addressing parameter uncertainty and the challenges posed by the censored observations.

 

Cite:  Vishal Singh, Akanksha Gupta and S. K. Upadhyay ANALYSIS OF JOINT MULTIPLY TYPE-II CENSORED DATA USING THE GIBBS SAMPLER ALGORITHM . Reliability: Theory & Applications. 2025, September 3(86):  422-434, DOI: https://doi.org/10.24412/1932-2321-2025-386-422-434


 

 

 

RELIABLE HYBRID OPTIMIZATION FOR SUPPLY CHAIN INVENTORY SYSTEMS

435-454

 

 

Ajay Singh Yadav, S. Viswanathan, Navin Ahlawat, Bhavani Viswanathan, Anupam Swami, Mohammed Abid

 

 

 

This study explores the optimization of blood supply chain inventory management through innovative approaches, specifically Bee Colony Optimization (BCO) and Genetic Algorithms (GA). The research addresses challenges in healthcare logistics, emphasizing the integration of organizational units involved in blood sourcing, production, distribution, and marketing. Key considerations include the potential conflicts between cost minimization in sourcing decisions and the focus on throughput in production and distribution. The study highlights the significance of achieving an optimal balance to ensure a reliable and efficient blood supply for patient care. Bee Colony Optimization and Genetic Algorithms, inspired by natural processes, offer promising solutions to the complexities of blood inventory management. BCO mimics collaborative foraging behavior, creating optimal paths marked by pheromones. Genetic Algorithms replicate natural selection to iteratively enhance solutions. The research aims to provide valuable insights into the application of these algorithms, contributing to the evolution of efficient blood supply chain management. The anticipated outcomes include improved healthcare logistics, ensuring timely access to blood products and enhancing patient safety and outcomes.

 

Cite:  Ajay Singh Yadav, S. Viswanathan, Navin Ahlawat, Bhavani Viswanathan, Anupam Swami, Mohammed Abid RELIABLE HYBRID OPTIMIZATION FOR SUPPLY CHAIN INVENTORY SYSTEMS. Reliability: Theory & Applications. 2025, September 3(86):  435-454, DOI: https://doi.org/10.24412/1932-2321-2025-386-435-454


 

 

 

ALPHA-POWER-BURR-HATKE-EXPONENTIAL MODEL: PROPERTIES, SIMULATIONS AND APPLICATIONS BASED ON UNCENSORED AND PROGRESSIVE TYPE-II-CENSORED SAMPLES

455-472

 

 

Adubisi O. D., Joshua T., David A. A.

 

 

 

This study introduced a novel two-parameter model known as the alpha power Burr Hatke exponential (APBHE) model, characterized by constant, increasing-constant, upside-down bathtub, decreasing and increasing failure shapes. Structural properties and basic reliability functions are derived. The Simulation study carried out for both uncensored and progressive type-II censored samples indicated that the maximum likelihood estimation (MLE) performed quite well in producing good parameter estimates at finite sample sizes and tend to the true parameter value quicker than the maximum spacing product (MBS) method with minimum bias. Specifically, the censored schemes simulation disclosed that the MSE and bias values decrease as the sample size increases for the various censoring proportions. To demonstrate the flexibility and relevance of the APBHE model, a real-life bladder-cancer dataset is examined and the APBHE model achieved the best performance when compared with other competing models. Additionally, the log-APBHE model and log-APBHE regression model functions are presented for further explorations. 

 

Cite:  Adubisi O. D., Joshua T., David A. A. ALPHA-POWER-BURR-HATKE-EXPONENTIAL MODEL: PROPERTIES, SIMULATIONS AND APPLICATIONS BASED ON UNCENSORED AND PROGRESSIVE TYPE-II-CENSORED SAMPLES. Reliability: Theory & Applications. 2025, September 3(86):  455-472, DOI: https://doi.org/10.24412/1932-2321-2025-386-455-472


 

 

 

MULTI- REFERENCE SKIP- LOT SAMPLING OF TYPE 3 (MR-SkSP-3)

473-484

 

 

Meby Joseph Manoj, Azarudheen S.

 

 

 

In the current industrial sector, the rate of defective products present in the lots has been decreasing and most of the products keeps up a good history of quality throughout the production also. Skip-lot sampling plans are the suitable acceptance sampling plan for the situations where the series of products shows a stable and excellent quality. The skip-lot sampling plans are still widely used because of its reduced sampling cost and efforts, because the plan only needs to inspect a fraction of the lots submitted after a continues series of lots with excellent quality. This approach makes the skip-lot plan more cost-effective than the other sampling plans, thus making it an economically important plan. The current study incorporated a modification on the skip-lot sampling of type 3 and designated it as multi- reference skip lot sampling of type 3. The proposed plan has the provision of having multiple reference plans in normal and skipping inspection of a skip-lot sampling plan, unlike the traditional skip-lot plans which has the same reference plan in all phases. The performance measures of the proposed plan are derived using the power series approach. A designing methodology to determine the optimal parameters for the plan using the unity value approach is also described with the help of a numerical illustration. Behaviour of the operating characteristic curves for varying set of parameters are also analysed for the plan. Comparison of the proposed plan is done between the conventional plans using performance measure values and graphical representations. This analysis shows that the new plan is able to effectively optimize the preferences of producer and consumer simultaneously, where the traditional plans fail to. The analysis is supported with the help of graphical representations and tabulated values. 

 

Cite:  Meby Joseph Manoj, Azarudheen S. MULTI- REFERENCE SKIP- LOT SAMPLING OF TYPE 3 (MR-SkSP-3). Reliability: Theory & Applications. 2025, September 3(86):  473-484, DOI: https://doi.org/10.24412/1932-2321-2025-386-473-484


 

 

 

ENHANCING ACCURACY IN ESTIMATING POPULATION MEAN THROUGH MODIFIED RATIO ESTIMATORS IN RANKED SET SAMPLING

485-494

 

 

S. A. Sabo, A. A. Osi, I. Z. Musa, H. U. Abubakar, A. Muhammad, U. Abubakar 

 

 

 

This study aimed to improve the ratio estimation under rank set sampling by proposing some new modified estimators using auxiliary information on the size of the sample. The expressions for the bias and mean squared error of the proposed modified estimators are derived up to the first order of approximation using Tailor series expansion. A theoretical efficiency comparison between the proposed and competing estimators was done and the conditions upon which the proposed estimators expect to outperform the competing estimators were stated. Results from the numerical work indicate that the new proposed improved estimators are better than the already existing ones, showing a lower mean square error, coefficient of variation, and a considerable gain in efficiency. The new proposed estimators emerge as the optimal choice, outperforming the competing ones, and should therefore be used in applications.

 

Cite:  S. A. Sabo, A. A. Osi, I. Z. Musa, H. U. Abubakar, A. Muhammad, U. Abubakar  ENHANCING ACCURACY IN ESTIMATING POPULATION MEAN THROUGH MODIFIED RATIO ESTIMATORS IN RANKED SET SAMPLING. Reliability: Theory & Applications. 2025, September 3(86):  485-494, DOI: https://doi.org/10.24412/1932-2321-2025-386-485-494


 

 

 

SURVEY ON NON-MARKOVIAN QUEUE WITH PHASE SERVICE USING SUPPLEMENTARY VARIABLE TECHNIQUE

495-518

 

 

Binay Kumar, Sudeep Singh Sanga, Aditya Kumar

 

 

 

In the present article, we provide a comprehensive overview and literature review on performance modeling of queueing systems with phase service, utilizing the supplementary variable technique. We discuss the scenarios that necessitate phase service and explain how the supplementary variable technique is applied to analyze non-Markovian models. Additionally, we offer a summary of the fundamental concepts and existing literature on queueing systems with phase service. Our review covers research conducted over the past decade (2014-2024) on queues featuring phase service, including aspects such as bulk arrival, service interruptions, and discouragement. The review systematically explores models incorporating bulk arrivals, service interruptions, customer discouragement, and other complex operational features. By consolidating recent advancements and identifying common modeling approaches, this work aims to provide valuable insights for researchers and practitioners engaged in the analysis and design of advanced queueing systems. 

 

Cite:  Binay Kumar, Sudeep Singh Sanga, Aditya Kumar SURVEY ON NON-MARKOVIAN QUEUE WITH PHASE SERVICE USING SUPPLEMENTARY VARIABLE TECHNIQUE. Reliability: Theory & Applications. 2025, September 3(86):  495-518, DOI: https://doi.org/10.24412/1932-2321-2025-386-495-518


 

 

 

MATHEMATICAL AND RELIABILITY MODELS OF MACHINE LEARNING ALGORITHMS FOR EARLY BRAIN CANCER DETECTION

519-532

 

 

Ajay Singh Yadav, Navin Ahlawat, Bhavani Viswanathan, Garima Pandey, Anupam Swami, Anjali Malik

 

 

 

Early detection of brain cancer is critical for improving patient outcomes, and this study explores the use of Logistic Regression, Reliability Modeling, and mathematical techniques for better diagnostic accuracy. Logistic Regression, a statistical model for binary classification, is used to predict tumor malignancy based on imaging features, offering probabilistic predictions that can guide clinical decisions. Reliability Modeling evaluates the performance and robustness of diagnostic systems, ensuring accurate detection despite varying conditions. By combining these methods, we can improve both the prediction accuracy and reliability of diagnostic systems. The research also integrates optimization and statistical inference to refine these models, ensuring they are both accurate and statistically sound. Hybrid models that combine deep learning with Logistic Regression further enhance the detection of brain tumors by leveraging the strengths of both approaches. The study underscores the potential of AI and mathematical models to revolutionize brain cancer diagnostics, offering more reliable, interpretable, and efficient tools for early detection and improved patient outcomes.

 

Cite:  Ajay Singh Yadav, Navin Ahlawat, Bhavani Viswanathan, Garima Pandey, Anupam Swami, Anjali Malik MATHEMATICAL AND RELIABILITY MODELS OF MACHINE LEARNING ALGORITHMS FOR EARLY BRAIN CANCER DETECTION. Reliability: Theory & Applications. 2025, September 3(86):  519-532, DOI: https://doi.org/10.24412/1932-2321-2025-386-519-532


 

 

 

IMPROVING THE QUALITY OF INTERVAL PATTERN RECOGNITION BY DIVIDING THE PATIENT SAMPLE IN MEDICAL RESEARCH

533-538

 

 

Gurami Tsitsiashvili, Vera Nevzorova, Pavel Dunts, Angelina Talko, Marina Osipova

 

 

 

In this paper, we consider a way to improve the quality of interval pattern recognition by dividing the sample into parts. This method is used to study erythrocyte and platelet germs of haematopoiesis for the ability to positively treat haematological patients from COVID-19. Along with this, this method of improving the quality of interval recognition is used to identify predictors of "difficult" tracheal intubation during artificial ventilation during anaesthetic support of surgical interventions. Despite the rather strong difference between these medical tasks, they are united in this research context by the possibility of improving the quality of recognition through a more specialized study of each sub sample of patients after dividing the sample into parts.

 

Cite:  Gurami Tsitsiashvili, Vera Nevzorova, Pavel Dunts, Angelina Talko, Marina Osipova IMPROVING THE QUALITY OF INTERVAL PATTERN RECOGNITION BY DIVIDING THE PATIENT SAMPLE IN MEDICAL RESEARCH. Reliability: Theory & Applications. 2025, September 3(86):  533-538, DOI: https://doi.org/10.24412/1932-2321-2025-386-533-538


 

 

 

EFFICIENT ESTIMATION OF POPULATION MEAN USING MEDIAN OF AUXILIARY VARIABLE AND SIMULATION UNDER SRS

539-550

 

 

RizwanYousuf

 

 

 

In this study, we propose two modified ratio estimators for the estimation of the population mean of a study variable using the median of an auxiliary variable. Theoretical expressions for the bias and mean squared error (MSE) of the proposed estimators are derived under simple random sampling. We establish the conditions under which these estimators outperform existing modified ratio estimators. To validate the theoretical findings, both an empirical study using natural population data and a comprehensive simulation study are conducted. The simulation results consistently demonstrate the superior efficiency of the proposed estimators across varying sample sizes and correlation structures. These findings highlight the practical applicability and robustness of the proposed estimators in survey sampling.

 

Cite:  RizwanYousuf EFFICIENT ESTIMATION OF POPULATION MEAN USING MEDIAN OF AUXILIARY VARIABLE AND SIMULATION UNDER SRS. Reliability: Theory & Applications. 2025, September 3(86):  539-550, DOI: https://doi.org/10.24412/1932-2321-2025-386-539-550


 

 

 

ENHANCING SHORE HARDNESS AND RELIABILITY OF SS 316L REINFORCED PMMA NANOCOMPOSITES THROUGH RESIN 3D PRINTING PROCESS OPTIMIZATION

551-561

 

 

Upender Punia, Ramesh Kumar Garg

 

 

 

Over the last ten years, 3D printing has made great progress and expanded its applicability in a number of industries, including dentistry. Dental items including temporary and permanent crowns, bridges, drill guides, and jaw implants may be made using resin 3D printing. To create novel 3D-printable materials and improve their functionality, a lot of research is being done. The shore hardness of 316L-reinforced PMMA nanocomposites for dental applications is examined in this work. Three important process parameters—exposure time (3-5 seconds), layer height (20-40 microns), and post-curing duration (10-30 minutes)—are used to assess the hardness of manufactured specimens. Shore hardness is optimised using Response Surface Methodology (RSM), which yields a maximum shore hardness of88.90 SHD at 4.75 seconds of exposure time, 30.7 microns of slice height, and 23.2 minutes of post-curing time. 

 

Cite:  Upender Punia, Ramesh Kumar Garg ENHANCING SHORE HARDNESS AND RELIABILITY OF SS 316L REINFORCED PMMA NANOCOMPOSITES THROUGH RESIN 3D PRINTING PROCESS OPTIMIZATION. Reliability: Theory & Applications. 2025, September 3(86):  551-561, DOI: https://doi.org/10.24412/1932-2321-2025-386-551-561


 

 

 

IMPACT OF FIBERS WEIGHT PROPORTION AND SURFACE TREATMENTS ON THE RELIABILITY OF HYBRID EPOXY COMPOSITE

562-572

 

 

Manjeet Chahar, Rajneesh Kumar

 

 

 

Natural fiber-reinforced composites (NFRCs) are attracting growing interest in many technical applications owing to their environmentally sustainable and economical properties. This study investigates the impact of weight proportion of fibers and surface treatments on the tensile strength of hybrid epoxy composites reinforced with hemp, jute, and bamboo. Prior to composite fabrication, the fibers underwent alkali and saline treatments at different concentrations (3, 5, and 7 wt. %). The composites were fabricated via the hand lay-up technique by varying wt. proportion of fibers (10,15, and 20 wt. %). The tensile strength is optimized using Response Surface Methodology (RSM), which yields highest tensile strength of 63.11 MPa at 14.24 wt. % of fibers fraction and 5.40 wt. % concentration of alkali treatment. Findings of this study demonstrate that reliability of the hybrid composite significantly enhanced due to improvement in strength of the composite. The treated hybrid composites have favourable properties, rendering them a feasible and sustainable option for automobile components and other lightweight structural applications. 

 

Cite:  Manjeet Chahar, Rajneesh Kumar IMPACT OF FIBERS WEIGHT PROPORTION AND SURFACE TREATMENTS ON THE RELIABILITY OF HYBRID EPOXY COMPOSITE. Reliability: Theory & Applications. 2025, September 3(86):  562-572, DOI: https://doi.org/10.24412/1932-2321-2025-386-562-572


 

 

 

COMPARISON OF CLASSICAL AND BAYESIAN APPROACHES FOR ESTIMATING THE SCALE PARAMETER OF THE INVERSE POWER RAYLEIGH DISTRIBUTION

573-586

 

 

Aadil Ahmad Mir, S.P. Ahmad, Sofi Mudasir Ahad

 

 

 

This manuscript investigates the parameter estimation of the Inverse Power Rayleigh Distribution (IPRD) using both Classical and Bayesian approaches. Parameters are estimated via Maximum Likelihood Estimation (MLE) and Bayesian methods under three prior assumptions: Jeffreys prior, extended Jeffreys prior, and quasi prior. Bayesian estimators, along with their associated risks, are evaluated using various symmetric and asymmetric loss functions, including the squared error loss function, Al-Bayyatis new loss function, precautionary loss function and entropy loss function. The performance of the estimators is assessed through simulated data based on the mean squared error (MSE) criterion. Results indicate that the Bayesian approach generally provides more accurate estimates with lower MSE compared to the classical MLE method.

 

Cite:  Aadil Ahmad Mir, S.P. Ahmad, Sofi Mudasir Ahad COMPARISON OF CLASSICAL AND BAYESIAN APPROACHES FOR ESTIMATING THE SCALE PARAMETER OF THE INVERSE POWER RAYLEIGH DISTRIBUTION. Reliability: Theory & Applications. 2025, September 3(86):  573-586, DOI: https://doi.org/10.24412/1932-2321-2025-386-573-586


 

 

 

THE IMPACT OF RAM ON SYSTEM PERFORMANCE: A REVIEW

587-591

 

 

Parveen Sihmar, Vikas Modgil, Sandeep Kumar

 

 

 

One of the requirements that industrial systems must meet is that they must function effectively for a prolonged period. The system's performance is a vital component for failure-free operation; yet, in actual fact, it is extremely rare for any production system to be completely failure-free. Over the course of the past twenty-five years, a comprehensive and critical literature assessment of reliability, maintainability, and availability (RAM) approaches has been carried out. These approaches have the potential to assist in the enhancement of the performance of complex systems. The review of a few publications resulted in the provision of comprehensive information regarding the historical and contemporary situation of RAM procedures in the research field and enterprises. A review of RAM tools and approaches can help in doing qualitative and quantitative analysis of complex systems. The author of this research tried to focus on a few of the key components of RAM methods. 

 

Cite:  Parveen Sihmar, Vikas Modgil, Sandeep Kumar THE IMPACT OF RAM ON SYSTEM PERFORMANCE: A REVIEW. Reliability: Theory & Applications. 2025, September 3(86):  587-591, DOI: https://doi.org/10.24412/1932-2321-2025-386-587-591


 

 

 

THE QUASI-STATIONARY DISTRIBUTION OF A COMPLEX TWO-UNIT REPAIRABLE SYSTEM

592-600

 

 

Miriam Kalpana Simon, Jasmine Rathi S., Late Dr. K. Shankar Bhat

 

 

 

Like the first-busy-period in a queuing system, the time-to-system-failure is an important characteristic of a reliability system. In some reliability systems the time-to-system-failure may be sufficiently large to allow the residual life of the system to settle down to a state of statistical equilibrium. The conditional limit distribution of the residual lifetime, also known as the quasi- stationary distribution, plays a vital role in the statistical analysis of such systems. In this work, the quasi-stationary distribution for the residual lifetime of a two-unit complex reparable system is obtained using regenerative stochastic process. The results of the study are numerically illustrated assuming exponential lifetime distribution for the units. 

 

Cite:  Miriam Kalpana Simon, Jasmine Rathi S., Late Dr. K. Shankar Bhat THE QUASI-STATIONARY DISTRIBUTION OF A COMPLEX TWO-UNIT REPAIRABLE SYSTEM. Reliability: Theory & Applications. 2025, September 3(86):  592-600, DOI: https://doi.org/10.24412/1932-2321-2025-386-592-600


 

 

 

LIFO-BASED OPTIMIZATION OF TWO-WAREHOUSE INVENTORY SYSTEMS WITH DETERIORATING ITEMS

601-613

 

 

Amit Kumar, Ajay Singh Yadav, Dharmendra Yadav, Bhavani Viswanathan

 

 

 

In this study, a two-warehouse inventory model for the red wine industry is presented, focusing on items that deteriorate. The model takes into account the effects of inflation and operates on the LIFO (Last In, First Out) distribution policy. The goal is to minimize the total inventory cost, including the cost of maintaining inventory and the cost of purchasing new inventory. The model assumes a constant and known demand for red wine over time, with no permitted shortages. The stock system consists of warehouse A and warehouse B, with starting stocks fixed in each case. Inventory balance equations track inventory levels at each warehouse, taking into account transfers between warehouses and customer demand. The LIFO shipping policy is implemented to determine the quantities transferred between warehouses. Inflation is factored into the model by adjusting the cost of buying new inventory. This adjustment may be based on historical inflation rates or other relevant factors. The objective function is to minimize the total inventory cost, taking into account inventory costs and inflation-adjusted purchasing costs. The model provides a framework for making decisions about stock levels and transfer rates between warehouses. By optimizing these decisions, the model aims to achieve cost savings while ensuring that demand is met without bottlenecks. The model results can serve as a guide for inventory management strategies in the red wine industry, taking into account the specific challenges presented by the spoiled nature of the product and the impact of inflation. 

 

Cite:  Amit Kumar, Ajay Singh Yadav, Dharmendra Yadav, Bhavani Viswanathan LIFO-BASED OPTIMIZATION OF TWO-WAREHOUSE INVENTORY SYSTEMS WITH DETERIORATING ITEMS. Reliability: Theory & Applications. 2025, September 3(86):  601-613, DOI: https://doi.org/10.24412/1932-2321-2025-386-601-613


 

 

 

STOCHASTIC MODELING AND ANALYSIS OF A PARALLEL SYSTEM WITH DIFFERING UNIT QUALITIES AND CATASTROPHIC FAILURES 

614-624

 

 

Priya Baloda, Amit Kumar, Vikas Garg

 

 

 

In this paper, we conduct a stochastic analysis of a system comprising of two dissimilar units operating in parallel. One unit, characterized by two distinct types of failures, is considered high merit, while the other unit, with only one type of malfunction, is deemed low merit. We introduce the concept of catastrophic failure for the system. It is assumed that a single serviceman is responsible for both repair and replacement tasks. A regenerative point-based approach is employed to estimate various reliability characteristics. Additionally, we analyze the proposed model graphically to illustrate the effects of failure, repair, and replacement rates on the system's mean time to system failure (MTSF), availability, and profit. 

 

Cite:  Priya Baloda, Amit Kumar, Vikas Garg STOCHASTIC MODELING AND ANALYSIS OF A PARALLEL SYSTEM WITH DIFFERING UNIT QUALITIES AND CATASTROPHIC FAILURES . Reliability: Theory & Applications. 2025, September 3(86):  614-624, DOI: https://doi.org/10.24412/1932-2321-2025-386-614-624


 

 

 

ANALYSIS OF METHODS FOR ELIMINATION OF THE BRUSH-CONTACT ASSEMBLY OF THE ASG OF WIND TURBINES

625-633

 

 

N.S. Mammadov, M. Marufov, K.M. Mukhtarova

 

 

 

Traditional generator designs that use brush-and-contact assemblies to transmit electric current between rotating and stationary parts of the device are subject to significant drawbacks. The main problems associated with the use of brush-and-contact assemblies include mechanical wear of brushes and slip rings, sparking, electrical losses and high operating costs, which leads to reduced reliability and increased maintenance costs. Elimination of brush-and-contact assemblies is an urgent task, since it allows to significantly increase the reliability of devices and simplify their operation, especially in difficult climate conditions and high wind turbine installations. The article analyzes two modern approaches to solving this problem: installation of a brushless exciter and use of a rotating transformer. Each of these methods has its own advantages and disadvantages. The general electrical circuit of a brushless exciter device based on an asynchronized synchronous generator is presented. The general electrical circuit of an asynchronized synchronous generator with a rotating transformer is also presented. An innovative solution is also considered, which involves installing a battery on the rotating part of the generator, which acts as a contactless power source for the rotor winding and provides energy storage. 

 

Cite:  N.S. Mammadov, M. Marufov, K.M. Mukhtarova ANALYSIS OF METHODS FOR ELIMINATION OF THE BRUSH-CONTACT ASSEMBLY OF THE ASG OF WIND TURBINES. Reliability: Theory & Applications. 2025, September 3(86):  625-633, DOI: https://doi.org/10.24412/1932-2321-2025-386-625-633


 

 

 

CONSTRUCTION OF COMPLETE STOCHASTIC LIFE CYCLES OF HIGHLY CRITICAL INFRASTRUCTURES

634-645

 

 

Sviatoslav Timashev, Anna Bushinskaya

 

 

 

The article describes a risk-based approach to constructing the full life cycle (LC) of HCI with accounting for climate change. In this case, the objective function (OF) of HCI risk management as a function of time is reduced to the generalized cost of operating a strategically important object in the time interval “'from (birth) cradle / to grave". The life cycle, built on the basis of these data, makes it possible to evaluate and predict: (1) the inherent design reliability of the HCI, (2) the probabilities of all types of failures of the HCI; (3) the monetary consequences of these failures; (4) risks associated with random times of diagnostics, repairs and restoration of HCI and with the moments of its failures; (5) the overall risk of HCI at each moment of its existence with accounting for climate change. 

 

Cite:  Sviatoslav Timashev, Anna Bushinskaya CONSTRUCTION OF COMPLETE STOCHASTIC LIFE CYCLES OF HIGHLY CRITICAL INFRASTRUCTURES. Reliability: Theory & Applications. 2025, September 3(86):  634-645, DOI: https://doi.org/10.24412/1932-2321-2025-386-634-645


 

 

 

EXPLORING SOME NEW CONTRIBUTION TO RAM AWADH DISTRIBUTION WITH COMPARATIVE PROPERTIES AND ITS APPLICATIONS

646-658

 

 

Manzoor A. Khanday, Rashid A. Ganaie, Aboubakar Ahmat Alwali Bourma, T. Vivekanandan, R. Shenbagaraja

 

 

 

In this study, a novel extension of the Ram Awadh distribution referred to as length biased Ram Awadh distribution is proposed and systematically developed. This distribution is constructed by applying length-biased transformation to the baseline Ram Awadh distribution, making it more suitable for modeling data where longer durations or larger values are more likely to be observed. A comprehensive exploration of the distribution's statistical properties is presented, including the derivation of moments, harmonic mean, reliability function, failure rate function, reverse hazard rate function, order statistics, entropy as well as the bonferroni and Lorenz curves. Parameter estimation is conducted through the maximum likelihood estimation method, ensuring robustness and efficiency. The practical utility and goodness of fit of the proposed model are demonstrated through its application to three real-life datasets, highlighting its flexibility and improved performance in empirical context.

 

Cite:  Manzoor A. Khanday, Rashid A. Ganaie, Aboubakar Ahmat Alwali Bourma, T. Vivekanandan, R. Shenbagaraja EXPLORING SOME NEW CONTRIBUTION TO RAM AWADH DISTRIBUTION WITH COMPARATIVE PROPERTIES AND ITS APPLICATIONS. Reliability: Theory & Applications. 2025, September 3(86):  646-658, DOI: https://doi.org/10.24412/1932-2321-2025-386-646-658


 

 

 

A COMPARATIVE STUDY OF GENERALIZED ARADHANA DISTRIBUTION WITH SIGNIFICANT STATISTICAL PROPERTIES AND APPLICATIONS

659-671

 

 

Rashid A. Ganaie, V. P. Soumya, R. Shenbagaraja,Manzoor A. Khanday

 

 

 

This study introduces a novel extension of the generalized Aradhana distribution, termed the length biased generalized Aradhana distribution. The proposed distribution is formulated by applying the length biased technique to the baseline generalized Aradhana distribution, enhancing its applicability in reliability and survival analysis. Fundamental statistical properties, including moments, order statistics, reliability functions and entropy are rigorously derived to characterize the distribution's behavior. The parameters of proposed model are estimated using the maximum likelihood estimation method to ensure statistical efficiency. To assess its practical utility, the distribution is applied to two real-world lifetime data sets, demonstrating its superior performance and robustness compared to existing models. These findings highlight the significance and applicability of the length biased generalized Aradhana distribution in modeling lifetime data. 

 

Cite:  Rashid A. Ganaie, V. P. Soumya, R. Shenbagaraja,Manzoor A. Khanday A COMPARATIVE STUDY OF GENERALIZED ARADHANA DISTRIBUTION WITH SIGNIFICANT STATISTICAL PROPERTIES AND APPLICATIONS. Reliability: Theory & Applications. 2025, September 3(86):  659-671, DOI: https://doi.org/10.24412/1932-2321-2025-386-659-671


 

 

 

ENHANCING PRODUCT QUALITY AND OPERATIONAL EFFICIENCY THROUGH STATISTICAL QUALITY CONTROL

672-681

 

 

M. A. Khanday, A. Jain, A. A. Khan, Y. Ahmad, A. A. Rather

 

 

 

The foundation of success in the modern business environment is maintaining constant quality and efficiency across supply chains. The paper presents a clear and comprehensive analysis as it delves into the complexities of quality control in the supply chain for makeup products. By utilizing a diverse range of statistical techniques, such as descriptive statistics, control chart analysis, and ANOVA, and able to reveal important information about defect rates and the overall field of quality control procedures. This research reveals the complex interactions between different elements that affect defect rates, with a focus on the crucial functions that lead time and shipping carriers play in the supply chain for makeup products. By means of a methodical and thorough examination, we not only reveal the stability that is innate to the manufacturing process but also identify critical areas that are ripe for improvement. Determine areas for improvement by carefully examining the data; this will set the stage for increased operational effectiveness and higher standards of quality. This paper bridges the gap between theoretical understanding and real- world applications, rather than just existing in the domain of theoretical conjecture. Provide participants in the makeup product supply chain with practical insights that can lead to observable outcomes by combining academic accuracy with real-world relevance. In order to enable stakeholders to confidently and precisely navigate the complexities of quality control, this paper acts as a beacon of guidance. Stakeholders can enhance operational performance, reduce risks, and foster a continuous improvement culture by Furthermore, by maintaining an intense focus on raising customer satisfaction, this analysis clears the path for long-term success in the competitive and dynamic makeup product market. 

 

Cite:  M. A. Khanday, A. Jain, A. A. Khan, Y. Ahmad, A. A. Rather ENHANCING PRODUCT QUALITY AND OPERATIONAL EFFICIENCY THROUGH STATISTICAL QUALITY CONTROL. Reliability: Theory & Applications. 2025, September 3(86):  672-681, DOI: https://doi.org/10.24412/1932-2321-2025-386-672-681


 

 

 

ANALYSIS OF MODELING METHODS OF LINEAR AND NONLINEAR AUTOMATIC CONTROL SYSTEMS 

682-689

 

 

S.M. Kerimova, S.J. Alimamedova

 

 

 

The article discusses the stability of automatic control systems (ACS). The stability of the automatic control system is the main characteristic of the automatic return of the system to its initial state of equilibrium after exposure to certain influencing factors on this system. In other words, it is the property of the system to maintain its resistance to external influences and its efficiency. The issue of reliability is aimed at preventing unforeseen and dangerous consequences of system instability, especially in such diverse fields as aviation, energy, and industry. A stable system ensures more accurate performance of the specified functions and is less prone to probable failure, and they can work for a long time without human intervention. An important place in the issue of determining the stability of ACS is occupied by the identification of errors that occur mainly during transients occurring in systems. The detected error is determined by the difference between the input signal (setpoint) and the input signal. In addition, the error that occurs in the system depends on different types of input signals, so these inputs can be stepwise, linear, etc. they can be typical. It should be noted that bias error analysis is useful only for stable systems. That is, before investigating an error in the system, it is necessary to determine the stability of this system. The article also considered the issue of calculating the error in the system with negative feedback. Using the Matlab/Simulink program, algorithms related to the detection of an error in the ACS are compiled. When studying the issues of ACS stability, the issue of regulating the gain coefficients of various types through a PID (ProportionaTIntegral-Derivative) regulator is being investigated. 

 

Cite:  S.M. Kerimova, S.J. Alimamedova ANALYSIS OF MODELING METHODS OF LINEAR AND NONLINEAR AUTOMATIC CONTROL SYSTEMS . Reliability: Theory & Applications. 2025, September 3(86):  682-689, DOI: https://doi.org/10.24412/1932-2321-2025-386-682-689


 

 

 

THE POWER GENERALIZED KAVYA MANOHARAN TRANSFORMATION: APPLICATIONS IN RELIABILITY AND LIFETIME REGRESSION

690-704

 

 

Jinet Mariya Jojy, Sajesh T. A., Nicy Sebastian

 

 

 

A new class of distributions is introduced through the exponentiated generalization of the Kavya Manoharan transformation, referred to as the Power Generalized Kavya Manoharan (PGKM) transformation. In parallel systems, applying power transformations to the distribution of individual components yields the system's overall distribution. This generalization enhances the model's flexibility and accuracy. In this context, we propose a transformation to generate a novel class of distributions, specifically by developing a distribution based on the Inverse Weibull distribution as the baseline. We investigate the behaviour of the hazard rates of these distributions, along with other analytical properties. Reliability measures for both single-component and multi-component stress-strength models are derived. The parameters of the proposed model are estimated using the maximum likelihood method, and simulation studies confirm the consistency of these estimates. Additionally, the new life distribution is applied to a real dataset, demonstrating superior fit when compared to various existing distributions in the literature. The distribution is further re-parametrized with location-scale parameters and employed in a lifetime regression analysis, with application provided to a practical dataset. 

 

Cite:  Jinet Mariya Jojy, Sajesh T. A., Nicy Sebastian THE POWER GENERALIZED KAVYA MANOHARAN TRANSFORMATION: APPLICATIONS IN RELIABILITY AND LIFETIME REGRESSION. Reliability: Theory & Applications. 2025, September 3(86):  690-704, DOI: https://doi.org/10.24412/1932-2321-2025-386-690-704


 

 

 

INFERENCES FOR ALPHA POWER TRANSFORMED INVERSE LINDLEY DISTRIBUTION BASED ON ORDER STATISTICS WITH APPLICATIONS

705-725

 

 

Sumit Kumar, Anju Goyal, Devendra Kumar, Narinder Kumar

 

 

 

The alpha power-transformed inverse Lindley distribution (APTIL) consist of one shape and one scale parameter. In some cases, the moments of the APTIL distribution may not exist due to its heavy tail, so we instead focus on the concept of inverse moments. In this paper, order statistics is used to derive the expression for moments, product moments and moment generating function for this distribution. The entropy of using order statistics for the APTIL distribution is also derived. Furthermore, tabulated values of the inverse moments of order statistics are provided for various sample sizes and parameter combinations. Three classical estimation techniques, viz., maximum product spacing estimators, least squares estimators, and weighted least squares estimators, are considered for parameter estimation and also evaluate the model parameters based on Type-II censored data. A Monte Carlo simulation-based approach is employed to assess the accuracy and validity of these estimators and the ensuing results. Finally, an empirical study using available real-life data sets demonstrates the utility of the distribution. 

 

Cite:  Sumit Kumar, Anju Goyal, Devendra Kumar, Narinder Kumar INFERENCES FOR ALPHA POWER TRANSFORMED INVERSE LINDLEY DISTRIBUTION BASED ON ORDER STATISTICS WITH APPLICATIONS. Reliability: Theory & Applications. 2025, September 3(86):  705-725, DOI: https://doi.org/10.24412/1932-2321-2025-386-705-725


 

 

 

IN FUZZY MENGER SPACE, CERTAIN FPT USING OCCASIONALLY WEAKLY COMPATIBLE MAPPING THAT USES A-CLAS FUNCTION

726-734

 

 

Heera Ahirwar, Kavita Shrivastava

 

 

 

In this paper, we present new common fixed point theorems in the setting of fuzzy Menger spaces by considering self-mappings that satisfy the condition of occasional weak compatibility. The analysis is enriched through the incorporation of A-class functions, which serve as control functions in the formulation of contractive type conditions. This approach allows for the generalization and extension of several known results in the field of fuzzy fixed point theory. The structure of fuzzy Menger spaces, combined with the flexibility of A-class functions, enables the establishment of sufficient conditions for the existence and uniqueness of common fixed points among a family of self-mappings. To support the theoretical results, we also provide illustrative examples that demonstrate the applicability and effectiveness of the proposed theorems. The findings contribute to the broader understanding of fixed point results in fuzzy environments and highlight the utility of occasionally weakly compatible mappings under generalized contractive settings. 

 

Cite:  Heera Ahirwar, Kavita Shrivastava IN FUZZY MENGER SPACE, CERTAIN FPT USING OCCASIONALLY WEAKLY COMPATIBLE MAPPING THAT USES A-CLAS FUNCTION. Reliability: Theory & Applications. 2025, September 3(86):  726-734, DOI: https://doi.org/10.24412/1932-2321-2025-386-726-734


 

 

 

RELIABILITY ASSESSMENT OF LOW-VOLT AGE NETWORKS UNDER LIGHTNING-INDUCED OVERVOLTAGES TRANSFERRED FROM MEDIUM-VOLTAGE SYSTEMS

735-742

 

 

I.A. Guseynova

 

 

 

This article investigates the reliability implications of lightning-induced overvoltages transferred from medium-voltage (MV) systems to low-voltage (LV) networks. Special emphasis is placed on the role of distribution transformers and the importance of accurate modeling for evaluating surge transfer mechanisms. Simulations and experimental comparisons reveal that conventional capacitive Pi-circuits significantly overestimate transferred voltages. The study highlights the key parameters influencing surge magnitudes, such as earth resistance, transformer proximity, line configuration, and insulator flashovers. Based on analytical models and real case studies, the paper provides recommendations for enhancing the surge immunity and operational reliability of LV systems under lightning conditions. 

 

Cite:  I.A. Guseynova RELIABILITY ASSESSMENT OF LOW-VOLT AGE NETWORKS UNDER LIGHTNING-INDUCED OVERVOLTAGES TRANSFERRED FROM MEDIUM-VOLTAGE SYSTEMS. Reliability: Theory & Applications. 2025, September 3(86):  735-742, DOI: https://doi.org/10.24412/1932-2321-2025-386-735-742


 

 

 

ENHANCING THE RELIABILITY OF RELAY- CONTACTOR CONTROL SYSTEMS IN INDUSTRIAL AND ENERGY APPLICATIONS

743-751

 

 

Gultakin Hasanova, Sonakhanim Babayeva

 

 

 

Relay-contactor systems remain essential components in power control and automation circuits, particularly in critical industrial and energy infrastructure. Despite the increasing use of solid- state and programmable devices, electromechanical relays and contactors are still widely employed due to their robustness, electromagnetic isolation, and high switching capabilities. However, their reliability is subject to various failure mechanisms including contact wear, coil overheating, and mechanical degradation. This paper presents a systematic analysis of these reliability challenges, supported by statistical modeling, environmental correction factors, and empirical data. Advanced diagnostic techniques and predictive maintenance strategies are discussed, including the integration of intelligent monitoring systems capable of tracking temperature, contact resistance, and response time. The study also explores architectural solutions for improving the redundancy and resilience of DC auxiliary power systems, focusing on protection automation. The technical and economic benefits of intelligent relay systems over conventional ones are demonstrated. Results indicate that adopting adaptive reliability management and smart diagnostics significantly reduces failure rates and improves system availability.

 

Cite:  Gultakin Hasanova, Sonakhanim Babayeva ENHANCING THE RELIABILITY OF RELAY- CONTACTOR CONTROL SYSTEMS IN INDUSTRIAL AND ENERGY APPLICATIONS. Reliability: Theory & Applications. 2025, September 3(86):  743-751, DOI: https://doi.org/10.24412/1932-2321-2025-386-743-751


 

 

 

FRACTIONAL INTEGRAL INEQUALITIES AND THEIR Q-EXTENSION

752-757

 

 

Farooq Ahmad, Ajjaz Maqbool, D.K. Jain, R. Vijaykrishnaraj, Aafaq A. Rather, D. Vedavathi Saraja, Syed M. Parveen, Raeesa Bashir , Showkat Ahmad Bhat

 

 

 

This paper aims to establish novel fractional integral inequalities for synchronous functions associated with the Chebyshev functional, incorporating the Gauss hyper geometric function. By employing advanced integral techniques, we derive refined bounds that extend and generalize existing results in the literature. The final section explores several special cases, particularly fractional integral inequalities involving Riemann-Liouville type fractional integral operators. Furthermore, we discuss potential applications of these findings in various mathematical and applied fields, highlighting their significance in fractional calculus and related domains. 

 

Cite:  Farooq Ahmad, Ajjaz Maqbool, D.K. Jain, R. Vijaykrishnaraj, Aafaq A. Rather, D. Vedavathi Saraja, Syed M. Parveen, Raeesa Bashir , Showkat Ahmad Bhat FRACTIONAL INTEGRAL INEQUALITIES AND THEIR Q-EXTENSION. Reliability: Theory & Applications. 2025, September 3(86):  752-757, DOI: https://doi.org/10.24412/1932-2321-2025-386-752-757


 

 

 

DESIGN OF SKIP LOT SAMPLING PLAN (SKSP-3) WITH SINGLE SAMPLING PLAN AS A REFERENCE PLAN USING BOREL DISTRIBUTION

758-768

 

 

Jayalakshmi S., Gopinath M.

 

 

 

Skip-lot sampling plans (SkSPs) have long been recognized as effective strategies for minimizing inspection efforts in quality control, especially within high-volume manufacturing settings. This study proposes a Skip-Lot Sampling Plan of Type SkSP-3, constructed using Single Sampling Plans (SSPs) by attributes, under the probabilistic framework defined by the Borel distribution. Given its suitability for modeling rare or intermittent events, the Borel distribution provides a solid foundation for representing quality characteristics in such contexts. The presentation of the proposed SkSP-3 plan is assessed by means of Operating Characteristic (OC) curves and benchmarked against corresponding SSPs under identical conditions. The results reveal that the SkSP-3 plan achieves notably smaller sample sizes while preserving similar OC behavior, particularly at low defect levels. This work contributes to the body of literature by presenting a robust and cost-effective methodology for designing SkSPs under Borel distribution assumptions, thereby enhancing inspection efficiency without compromising quality standards. 

 

Cite:  Jayalakshmi S., Gopinath M. DESIGN OF SKIP LOT SAMPLING PLAN (SKSP-3) WITH SINGLE SAMPLING PLAN AS A REFERENCE PLAN USING BOREL DISTRIBUTION. Reliability: Theory & Applications. 2025, September 3(86):  758-768, DOI: https://doi.org/10.24412/1932-2321-2025-386-758-768


 

 

 

ANALYZING SOLUTIONS OF FUZZY NABLA DYNAMIC EQUATIONS ON TIMESCALES: A GENERALIZED HUKUHARA APPROACH

769-783

 

 

Leelavathi R., Hari Kishore R., Mohana Rupa S. V. D., Muneera A.

 

 

 

In this paper, we study linear first-order fuzzy nabla dynamic equations on time scales (LFNDET's) under the framework of generalized Hukuhara nabla differentiability and also interpret various results of LFNDET's by employing the Variation of constant formula. A key result concerns the generalized nabla Hukuhara derivative for the product of a crisp function and a fuzzy function on time scales. Furthermore, we derive solutions to these equations using various approaches to generalized Hukuhara nabla differentiability. The behavior of these solutions highlights the importance and applicability of the generalized fuzzy nabla derivative in the context of nabla dynamic equations on time scales. 

 

Cite:  Leelavathi R., Hari Kishore R., Mohana Rupa S. V. D., Muneera A. ANALYZING SOLUTIONS OF FUZZY NABLA DYNAMIC EQUATIONS ON TIMESCALES: A GENERALIZED HUKUHARA APPROACH. Reliability: Theory & Applications. 2025, September 3(86):  769-783, DOI: https://doi.org/10.24412/1932-2321-2025-386-769-783


 

 

 

EXPLORING REDUNDANCY OPTIMIZATION TECHNIQUES FOR SYSTEM PERFORMANCE 

784-800

 

 

Parveen Kumar, Dalip Singh, Anil Kumar Taneja

 

 

 

System reliability optimization remains a dynamic and evolving challenge, influenced by continuous advancements in mathematical modeling, engineering innovation, and management strategies. This study includes documents on reliability, availability, maintainability, dependability, testability, cost-benefit analysis, life-cycle failures, maintenance modeling, and asset integrity management. However, this article is mainly concerned with documents that focus on redundancy optimization problems (i.e., k out of n system, warm, hot, cold standby redundancy, system reliability analysis in different failure and repair conditions, redundancy allocation in several system configurations, and so on) that apply to Telecommunications, Aerospace and Aviation, Industrial Automation, Network Servers and IT Systems, Transportation Systems. In addition, documents on the Oil and Gas Industry, Data Centers, and critical Infrastructure that are part of process industries are included. We analyze as many documents as possible by combining commonly used keywords. Additionally, the paper identifies emerging trends such as adaptive and hybrid redundancy strategies and the integration of intelligent techniques like Supplymentry variable techniques, regenerative point techniques, Genetic algorithm, and machine learning for real-time reliability management. By synthesizing findings from recent literature, this review aims to guide future research and practical implementations, supporting the design of cost-effective, robust, and resilient systems for modern computing environments.

 

Cite:  Parveen Kumar, Dalip Singh, Anil Kumar Taneja EXPLORING REDUNDANCY OPTIMIZATION TECHNIQUES FOR SYSTEM PERFORMANCE . Reliability: Theory & Applications. 2025, September 3(86):  784-800, DOI: https://doi.org/10.24412/1932-2321-2025-386-784-800


 

 

 

TWO STAGE FLOW SHOP SCHEDULING PROBLEM INCLUDING PROBABILITY UNDER LR FUZZY NUMBER

801-815

 

 

Pooja Kaushik, Deepak Gupta, Sonia Goel

 

 

 

Often known as the hybrid flow shop (HFS), the scheduling of flow shops with several parallel machines per stage is a challenging integrated problem that arises in many real-world scenarios. This study addresses bi stage flow shop scheduling problem involving parallel equipotential machines at each stage, where processing times are characterized as LR-type fuzzy numbers to encapsulate inherent uncertainties. Recognizing the criticality of minimizing the makespan under imprecise conditions, we employ four distinct reference functions to compute fuzzy makespan, thereby offering a diversified perspective on solution robustness. Four distinct fuzzy ranking (reference) functions are employed for defuzzification and comparison. The scheduling problem is solved using a Branch and Bound (B&B) algorithm tailored to accommodate fuzzy parameters and parallel machine constraints. Comparative analyses with an adapted version of branch and bound method are conducted to benchmark performance under varying degrees of fuzziness. Results underscore the efficacy and adaptability of the proposed approach, revealing nuanced improvements in makespan estimation and scheduling performance across varying fuzziness levels. This investigation not only enriches the theoretical landscape of fuzzy scheduling but also provides practical insights for complex manufacturing systems operating under uncertainty. This work not only extends classical scheduling methodologies into the fuzzy domain but also highlights the potential of integrating multiple reference functions within exact solution frameworks. The objective is to minimize the makespan under fuzzy conditions. To handle the fuzziness in processing times, A comparative analysis of the results obtained using each reference function is conducted to evaluate their effectiveness in producing optimal or near-optimal schedules. The study highlights the impact of the choice of reference function on the computational efficiency and solution quality, offering insights for better decision-making in uncertain manufacturing scenarios. These functions serve to transform fuzzy numbers into comparable crisp values, thereby enabling traditional scheduling algorithms to process the data effectively. The focus of this research is to evaluate the impact of each reference function on the scheduling performance and to analyze the variation in results with respect to makespan minimization. The findings offer significant theoretical contributions to fuzzy scheduling literature and practical implications for industries where uncertainty in processing times is a critical factor. 

 

Cite:  Pooja Kaushik, Deepak Gupta, Sonia Goel TWO STAGE FLOW SHOP SCHEDULING PROBLEM INCLUDING PROBABILITY UNDER LR FUZZY NUMBER. Reliability: Theory & Applications. 2025, September 3(86):  801-815, DOI: https://doi.org/10.24412/1932-2321-2025-386-801-815


 

FERMATEAN QUADRIPARTITIONED NEUTROSOPHIC FUZZY GRAPH

816-828

 

 

V. Divya, J. Jesintha Rosline

 

 

 

A fuzzy graph is a mathematical technique that represents relationship of an objects with uncertainty or imprecision, using nodes and edges with membership degrees to indicate the strength of connections. It provides an important paradigm for modelling and handling real world optimization tasks. Neutrosophic graphs extend classical graph theory to handle uncertain, imprecise and inconsistent information, enabling the modeling of complex relationships with varying degrees of truth, indeterminacy and falsity. This framework provides a more nuanced understanding of complex systems, allowing for improved accuracy and increased flexibility in decision-making, network analysis and optimization problems. Neutrosophic graphs can be applied to various fields, including multi-criteria decision-making, supply chain management and logistics, where uncertain or imprecise data is common. The extension of Neutrosophic set is the Quadripartitioned Neutrosophic Set. The division of indeterminacy function of the Neutrosophic set into the contradiction and ignorance component is termed as Quadripartitioned Neutrosophic Set. Associated with each vertex are values of truth, contradiction, ignorance and falsity that reflects it characteristics of a graph. Similarly, for each edge, these values signify the strength or reliability of the relationship between the connected vertices. Quadripartitioned Neutrosophic Fuzzy graph gives an accurate representation of uncertainty which leads to a greater clarity of complex systems and relationships. It has an emerging applications in social network analysis, image processing and decision making systems. Fermatean Neutrosophic Graph is a hybrid model of Fermatean and Neutrosophic graph. This enhancement provides an increased capacity to handle uncertain and unclear data. In contrast to traditional neutrosophic values, this framework operates with truth, indeterminacy and falsity membership degrees constrained by the condition that the sum of their third powers is less than or equal to two. In this article, a new graph is defined called Fermatean Quadripartitioned Neutrosophic Fuzzy Graph (FQNFG). We proposed the order, size, complete, complement and strong of Fermatean Quadripartitioned Neutrosophic Fuzzy Graph. Furthermore, the paper establishes operations for FQNFG such as composition, Cartesian product, Cross product and lexicographic product are also studied. 

 

Cite:  V. Divya, J. Jesintha Rosline FERMATEAN QUADRIPARTITIONED NEUTROSOPHIC FUZZY GRAPH. Reliability: Theory & Applications. 2025, September 3(86):  816-828, DOI: https://doi.org/10.24412/1932-2321-2025-386-816-828


 

RELIABILITY BASED AN ATTRIBUTE CONTROL CHART USING EXPONENTIATED EXPONENTIAL- POISSON DISTRIBUTION UNDER HYBRID CENSORING

829-840

 

 

B. Gokila, A. Sheik Abdullah

 

 

 

The Exponentiated Exponential-Poisson (EEP) distribution, an advanced extension of traditional lifetime models, offers greater adaptability in representing product lifetimes by more precisely capturing variations in failure rates. To handle incomplete lifetime data, a Hybrid censoring technique is employed, combining elements of both Type-I and Type-11 censoring to establish a more robust methodology for lifetime analysis. Naturally, np control charts are used to monitor the count of defective units within a sample. The primary aim is to detect shifts in product lifetime distributions, which are crucial for quality control and reliability assessment. However, this study introduces a modification to the control chart, shifting its focus from simply counting failures to tracking the median lifetime, thereby enhancing its capability to identify changes in product reliability over time. The efficiency of the control chart is measured using the Average Run Length (ARE), which estimates the expected number of observations before an out-of-control signal is triggered. By carefully adjusting the chart's parameters, the study ensures that the in-control ARL aligns closely with a predefined target, thereby improving its reliability. This research is dedicated to developing an np control chart designed to monitor the median lifetime of products that follow the EEP distribution within a Hybrid censoring Scheme. Numerical examples and simulated data are provided to illustrate its real-world applicability. By optimizing control chart parameters based on ARL, the study enhances monitoring precision for product reliability, making it a valuable tool in industries where accurate lifetime assessment is critical. 

 

Cite:  B. Gokila, A. Sheik Abdullah RELIABILITY BASED AN ATTRIBUTE CONTROL CHART USING EXPONENTIATED EXPONENTIAL- POISSON DISTRIBUTION UNDER HYBRID CENSORING. Reliability: Theory & Applications. 2025, September 3(86):  829-840, DOI: https://doi.org/10.24412/1932-2321-2025-386-829-840


 

 

 

ENHANCING THE RELIABILITY OF POWER SYSTEMS BY OPTIMIZING LIGHTNING PROTECTION OF OVERHEAD TRANSMISSION LINES

841-852

 

 

Elbrus Ahmedov, Kubra Mukhtarova

 

 

 

This paper addresses the reliability issues of power systems caused by lightning-induced overvoltages resulting from lightning strikes to components of overhead transmission lines (OHL). It is demonstrated that lightning discharges are one of the key causes of transmission line outages and significant economic losses. A method is proposed to improve the efficiency of lightning protection by upgrading the design of lightning protection cables using V-shaped metallic elements to increase the protection zone. Calculations were carried out to assess the expansion of the protection zone depending on the geometrical parameters of the design. A mathematical model was developed and implemented in the MATLAB Simulink environment to analyze the behavior of OHL under direct lightning strikes to the shield wire and phase conductors. The model takes into account lightning current parameters, structural characteristics of supports, grounding device properties, and insulation parameters. Simulation results showed a significant influence of grounding resistance on the level of resulting overvoltages and the effectiveness of lightning protection. The proposed technical solutions can be used to enhance the lightning resistance and operational reliability of overhead transmission lines, especially in regions with high lightning activity. 

 

Cite:  Elbrus Ahmedov, Kubra Mukhtarova ENHANCING THE RELIABILITY OF POWER SYSTEMS BY OPTIMIZING LIGHTNING PROTECTION OF OVERHEAD TRANSMISSION LINES. Reliability: Theory & Applications. 2025, September 3(86):  841-852, DOI: https://doi.org/10.24412/1932-2321-2025-386-841-852

 

 

 

ON RELIABILITY STRESS-STRENGTH MODEL USES SHOCK-MODEL APPROACH TO FOLLOW MUKHERJEE-ISLAM DISTRIBUTION

853-861

 

 

Vijayakumar. B., M. Manoharan

 

 

 

A component or system exposed to shocks will result in system or device damage. The strength of a produced product is a variable quantity that requires modelling as a random variable. It is necessary to evaluate the stress conditions of the operating system. Strength and stress are both thought of as random variables, which is made clear by the term "stress-strength model." With the inter-arrival time following the Mukherjee-Islam distribution and strength following an exponential distribution, we attempted to create a model in this study. Graphs are used to support numerical examples that are provided. 

 

Cite:  Vijayakumar. B., M. Manoharan ON RELIABILITY STRESS-STRENGTH MODEL USES SHOCK-MODEL APPROACH TO FOLLOW MUKHERJEE-ISLAM DISTRIBUTION. Reliability: Theory & Applications. 2025, September 3(86):  853-861, DOI: https://doi.org/10.24412/1932-2321-2025-386-853-861


 

 

 

DESIGN AND FABRICATION OF HIGH-GAIN, LOW CROSS-POLARIZATION PLANAR VIVALDI ANTENNA FOR UWB APPLICATIONS

862-874

 

 

Balvant J Makwana, Shahid S. Modasiya

 

 

 

This paper presents the design, simulation, and experimental validation of a corrugated Vivaldi antenna optimized for ultra-wideband (UWB) operation at high bandwidth. Fabricated on glass epoxy substrate, the antenna employs edge corrugations to minimize cross-polarization while maintaining high gain across the operational bandwidth. Full-wave electromagnetic simulations guided the design optimization, with radiation patterns and return loss parameters serving as key performance metrics. A prototype was fabricated and tested in an anechoic chamber, yielding a measured high gain with a very good peak gain over a wide range of frequency. Cross-polarization levels were effectively suppressed, ranging from approximately very low at both high and low frequencies. The close agreement between simulated and measured return loss parameters with impedance matching better and radiation characteristics validates the proposed design methodology. The presented approach confirms that cost-effective glass epoxy substrates can achieve performance comparable to specialized high-frequency materials when combined with strategic geometric modifications. The design is well suited for UWB applications in radar, wireless communication, and microwave imaging systems.

 

Cite:  Balvant J Makwana, Shahid S. Modasiya DESIGN AND FABRICATION OF HIGH-GAIN, LOW CROSS-POLARIZATION PLANAR VIVALDI ANTENNA FOR UWB APPLICATIONS. Reliability: Theory & Applications. 2025, September 3(86):  862-874, DOI: https://doi.org/10.24412/1932-2321-2025-386-862-874


 

 

 

AIRPORT SAFETY MANAGEMENT: A PROACTIVE MODEL BASED ON RISK ASSESSMENT AND BENCHMARKING

875-891

 

 

Abdellah Hanine, Abdellah El Barkany

 

 

 

This study presents a practical, context-sensitive approach to managing airport safety that combines the PDCA cycle with benchmarking techniques within a structured risk assessment framework. Given that ensuring operational safety in airports requires precisely recognizing, classifying, and successfully mitigating specific hazards, this study addresses this issue by creating a tailored risk assessment table. This tool, designed specifically for airport environments, clearly categorizes hazards based on their likelihood and severity and uses a novel equation developed in this study to correctly determine Safety Performance Indicators (SPI) and Safety Performance Targets (SPT). These indicators allow safety managers to effectively track performance trends, compare outcomes to other airports, and align safety policies with ICAO regulations. The cyclical nature of repetitive improvement in PDCA is assured, and value is added through benchmarking by applying tested best practices, enhancing the quality of decisions. A case study with airport safety practitioners establishes the practical applicability and value of this methodology in risk prioritization and pushing forward the drivers of corrective action. Collectively, the results demonstrate how this strategy supports proactive risk control and operational safety, and develops a sustainable culture of continuous improvement—a key component of effective airport safety management.

 

Cite:  Hanine, A., El Barkany, A. AIRPORT SAFETY MANAGEMENT: A PROACTIVE MODEL BASED ON RISK ASSESSMENT AND BENCHMARKING. Reliability: Theory & Applications. 2025, September 3(86):  875-891, DOI: https://doi.org/10.24412/1932-2321-2025-386-875-891


 

 

 

ON COPING WITH CENSORING IN SURVIVAL DATA USING FUZZY THEORY

892-898

 

 

Jaisankar, R., Haripriya, H.

 

 

 

Aim: The problem of censoring is the main concern in Survival Analysis which makes the analysis complex and may lead to unreliable results like less precise parameter/survival/hazard estimates, wider confidence intervals, reduced power to detect differences between groups, sometimes especially when the proportion of censored observations is high. In particular, if the censoring is informative that is reacted to the event, serious bias may be expected to present in the estimates. Omitting censored observations prices with loss of information and adding them is often embedded with a lack of information. It is proposed to implement fuzzy methodology for dealing with censored observations in Survival data so as to minimize their impact on the survival/hazard estimates. This paper suggests a modified approach based on the Fuzzy Theory, in which, the censored observations could be incorporated effectively. Methods: Many statistical procedures are advised to tackle censoring, in both parametric and non-parametric realms. However, their application mainly depend on the nature of censoring, whether right or left or interval censored. Even when their applied, still some lacuna may persist which could be completely eradicated when there is no censoring. Different types of fuzzy numbers are applied both to the censored and uncensored observations according to their nature and the results of the same were tested in case of the non-parametric procedure, the Kaplan-Meier estimator, using log rank test. Results: On the application of the proposed methodology one may obtain the survival probabilities which are reasonably calculated for even censored observations. The median survival time observed by the application of this methodology gives lesser value than the median obtained by the classical Kaplan eier method. The survival curve obtained by the proposed method is different from the survival curve of the classical Kaplan eier method and since the proposed methodology addresses all points of time and hence may give reliable estimates of survival probability. Conclusion: When compared with the classical Kaplan-Meier method, the proposal method gives survival probabilities which are slightly differ from the estimate obtained from non-fuzzy methodology. Since the survival probabilities can be calculated even for censored observations using fuzzy numbers, it is expected that the proposed modelling may be better than the classical Kaplan-Meier estimator.

 

Cite:  Jaisankar, R., Haripriya, H. ON COPING WITH CENSORING IN SURVIVAL DATA USING FUZZY THEORY. Reliability: Theory & Applications. 2025, September 3(86):  892-898, DOI: https://doi.org/10.24412/1932-2321-2025-386-892-898


 

 

 

BIOGEOGRAPHY-BASED RELIABILITY OPTIMIZATION

899-908

 

 

Deepika Garg, Sarita Devi, Doorgeshwaree Devi Heeramun, Nakul Vashishth

 

 

 

Biogeography-based optimization (BBO) is an effective optimization algorithm originally introduced by Dan Simon in 2008. It is inspired by the principles of biogeography. It mimics the process of migration and colonization of different species, where the behavior of species is determined by their habitats and the available resources. However, BBO can suffer from slow convergence and premature convergence for high-dimensional optimization problems. To address these issues, opposition-based learning (OBL) has been integrated with BBO. OBL uses the concept of generating an opposite solution to an existing solution and combining them to form a new search direction. This helps to improve the diversity of the population and accelerate the convergence speed of the algorithm. The combination of BBO and OBL has shown promising results in solving various optimization problems, including engineering design, scheduling, and feature selection. This approach has proved to be efficient and robust, making it an attractive alternative to other optimization algorithms. In this research study, the redundancy Allocation Problem (RAP) is solved with BBO and OBL-BBO. Computational results confirm the robustness and superiority of this new model over previous ones in optimizing the reliability of the system. Besides, the proposed algorithm OBL-BBO outperforms the previous ones BBO in finding good results. 

 

Cite:  Deepika Garg, Sarita Devi, Doorgeshwaree Devi Heeramun, Nakul Vashishth BIOGEOGRAPHY-BASED RELIABILITY OPTIMIZATION. Reliability: Theory & Applications. 2025, September 3(86):  899-908, DOI: https://doi.org/10.24412/1932-2321-2025-386-899-908


 

 

 

IMPROVING THE RELIABILITY OF SOLAR ENERGY SYSTEMS USING FLOATING PHOTOVOLTAIC TECHNOLOGIES

909-919

 

 

M.T.Babayev

 

 

 

This paper explores floating solar panels (FSPs) as a promising and cost-effective solution for enhancing the reliability and sustainability of solar power systems. The analysis focuses on the technical, environmental, and economic benefits of FSPs compared to traditional land-based installations. Floating systems offer improved operational reliability and energy efficiency due to natural cooling, land conservation, lower environmental impact, and reduced water evaporation — particularly vital in regions with limited freshwater resources. Deploying FSPs on artificial reservoirs and flooded quarries not only reduces land-use pressure but also contributes to lower capital and operational expenditures. Case studies from Azerbaijan and Japan demonstrate the reliability, resilience, and ecological viability of floating solar solutions under various climatic conditions. Although initial investments may be higher, long-term assessments reveal that FSPs can deliver more consistent performance and greater cost-effectiveness in regions with high solar irradiance and available water surfaces. The paper provides a comprehensive overview of floating photovoltaic technologies, highlighting their role in improving the reliability and stability of solar energy supply.

 

Cite:  M.T.Babayev IMPROVING THE RELIABILITY OF SOLAR ENERGY SYSTEMS USING FLOATING PHOTOVOLTAIC TECHNOLOGIES. Reliability: Theory & Applications. 2025, September 3(86):  909-919, DOI: https://doi.org/10.24412/1932-2321-2025-386-909-919

 

 

 

RELIABILITY-BASED OPTIMIZATION OF TWO-WAREHOUSE SUPPLY CHAIN MODELS

920-933

 

 

Ajay Singh Yadav, S. Viswanathan, Navin Ahlawat, Bhavani Viswanathan, Anupam Swami

 

 

 

This study presents a reliability-based optimization framework for managing a two-warehouse inventory system in the dairy industry, specifically addressing the complexities posed by product spoilage, shortages, and inflation. The proposed mathematical model integrates key inventory management principles with spoilage dynamics, shortage scenarios, and economic inflation, under a First-In-First- Out (FIFO) dispatching policy. By prioritizing the shipment of older stock, the model aims to reduce spoilage and enhance product turnover. It incorporates dairy product expiration rates to determine optimal replenishment and dispatch strategies while also identifying and mitigating potential operational bottlenecks. Additionally, the influence of inflation on inventory-related costs is embedded within the model to reflect real-world economic fluctuations. Through the application of advanced optimization algorithms implemented in MATLAB, the model seeks to minimize total inventory costs and improve supply chain efficiency. Overall, this research offers a comprehensive and practical tool for enhancing inventory decision-making in perishable goods industries like dairy. 

 

Cite:  Ajay Singh Yadav, S. Viswanathan, Navin Ahlawat, Bhavani Viswanathan, Anupam Swami RELIABILITY-BASED OPTIMIZATION OF TWO-WAREHOUSE SUPPLY CHAIN MODELS. Reliability: Theory & Applications. 2025, September 3(86):  920-933, DOI: https://doi.org/10.24412/1932-2321-2025-386-920-933


 

 

 

ANALYSIS OF M, MAP/PH/2 NON- PREEMPTIVE PRIORITY QUEUEING INVENTORY SYSTEM WITH BREAKDOWN, REPAIR AND (s, S) POLICY 

934-948

 

 

G. Ayyappan, M. Thilakavathy

 

 

 

We analyze a non-preemptive priority queueing model in this research that has two heterogeneous servers, each of which has its own queue. Queue 1 possesses a low priority status with infinite capacity and queue 2 possesses a high priority status with finite capacity. We made the assumption that arrival follows M, MAP and service time follows Phase-type distribution. Server 1 is always available in the system; Server 2 is an unreliable server. With a (s, S) policy, the inventory is filled up and an exponential distribution is scheduled for the replenishment time. Using the matrix analytical approach, a stationary probability vector was assessed, and a stability criterion was created for our system. Performance metrics are also studied using this technique. Both two and three-dimensional displays are used to show the numerical examples.

 

Cite:  G. Ayyappan, M. Thilakavathy ANALYSIS OF M, MAP/PH/2 NON- PREEMPTIVE PRIORITY QUEUEING INVENTORY SYSTEM WITH BREAKDOWN, REPAIR AND (s, S) POLICY . Reliability: Theory & Applications. 2025, September 3(86):  934-948, DOI: https://doi.org/10.24412/1932-2321-2025-386-934-948


 

 

 

ABOUT WAYS TO INCREASE RELIABILITY AND ECONOMY OF STEAM BOILER INSTALLATIONS OF BLOCK POWER PLANTS

949-958

 

 

Farzaliyev Y.Z.

 

 

 

The new method and algorithm of management by reliability and profitability of work of steam boiler installations block power stations is developed. The essence of a method is reduced to definition of "weak parts» and to formation of recommendations. In a basis of a database and program model, there are results of measurement and calculation of technical and economic parameters steam boiler installations. And the method allows to formulate the main directions of increasing the efficiency of individual control steam boiler installations and steam boiler installations of power plants as a whole. Improving the efficiency management system of the steam boiler installations allows, first of all, to reduce operating costs. The developed method allows us to consider the obtained results as methodological support for personnel in organizing the operation, maintenance and repair of steam boiler installation. Therefore, the relevance of this problem is obvious 

 

Cite:  Farzaliyev Y.Z. ABOUT WAYS TO INCREASE RELIABILITY AND ECONOMY OF STEAM BOILER INSTALLATIONS OF BLOCK POWER PLANTS. Reliability: Theory & Applications. 2025, September 3(86):  949-958, DOI: https://doi.org/10.24412/1932-2321-2025-386-949-958


 

 

 

A NOVEL METHOD TO ASSESSING PROCESS VARIATION WITH A CONFIDENCE INTERVAL OF SAMPLE STANDARD DEVIATION

959-964

 

 

Boya Venkatesu, G. Siva, Christophe Chesneau, V. Sai Sarada

 

 

 

One of the great tools of statistical process control for evaluating patterns of variation in the process is the control chart. In this article, we focus on developing a new approach to estimating process parameters in a control chart using confidence intervals (CIs) of sample standard deviations. They have the property of providing additional information about the quality of the estimate. A Monte Carlo simulation is used to investigate the accuracy of the obtained CIs. The performance of the classical and new approaches is compared in terms of standard error using simulated samples. The simulation results show that the new approach outperforms the classical approach.

 

Cite:  Boya Venkatesu, G. Siva, Christophe Chesneau, V. Sai Sarada A NOVEL METHOD TO ASSESSING PROCESS VARIATION WITH A CONFIDENCE INTERVAL OF SAMPLE STANDARD DEVIATION. Reliability: Theory & Applications. 2025, September 3(86):  959-964, DOI: https://doi.org/10.24412/1932-2321-2025-386-959-964


 

 

 

DIFFERENT ESTIMATION METHODS AND VALIDATION FOR THE EXTENSION EXPONENTIAL DISTRIBUTION

965-980

 

 

Rochdi Nouadri, Nacira Seddik-Ameur, Khaoula Aidi

 

 

 

This study investigates the extended exponential distribution proposed by Nadarajah and Haghighi, which can effectively model data with a mode at zero and accommodate varying hazard rates—whether increasing, decreasing, or constant. Unlike other distributions, it allows for scenarios where the hazard function increases while the probability density function decreases monotonically. The focus is on exploring alternative estimation methods to maximum likelihood estimation for this distribution, including the maximum product of spacing, Cramer-von Mises, Anderson-Darling, Right-tail Anderson-Darling, Left-tail Anderson-Darling, and Kolmogorov- Smirnov tests. A novel approach using initial data is proposed to develop an effective goodness-of- fit criterion tailored for validating this model. Extensive simulations with thousands of samples are conducted to assess the performance of these estimation methods and the practicality of the proposed goodness-of-fit test. Real data applications are also utilized to demonstrate the applicability and effectiveness of the extended exponential distribution in real-world scenarios. This research expands the statistical modelling toolkit by providing robust estimation techniques and validation criteria specifically designed for the characteristics of the extended exponential distribution. 

 

Cite:  Rochdi Nouadri, Nacira Seddik-Ameur, Khaoula Aidi DIFFERENT ESTIMATION METHODS AND VALIDATION FOR THE EXTENSION EXPONENTIAL DISTRIBUTION. Reliability: Theory & Applications. 2025, September 3(86):  965-980, DOI: https://doi.org/10.24412/1932-2321-2025-386-965-980


 

 

 

CONSTRUCTION OF A NEW ATTRIBUTE CONTROL CHART BASED ON RAYLEIGH DISTRIBUTION UNDER HYBRID CENSORING - A BAYESIAN APPROACH

981-989

 

 

T. Kavitha, M. Gunasekaran

 

 

 

Statistical Process Control (SPC) is a quality control approach that makes use of statistical tools to understand, monitor, and improve a process. A control chart is a tool for monitoring process performance that consists of a visual indication to detect anomalous deviations because of assignable causes. This chart compares the values of a quality attribute to the control limits. In the quality control process, the control chart is often generated by ignoring parameter uncertainty. The identification of changes in the parameter(s) within the probability distribution of one or more process-related variables is an essential part of monitoring. Estimating the parameters is essential since this might have an impact on the control chart's long-term performance in a controlled or out-of-control condition. This article provides a novel attribute control chart in the form of a Bayesian approach based on the Rayleigh lifetime distribution and the Hybrid censoring technique. A Bayesian approach will be used to calculate the control chart parameters and average run length. The control chart parameters are determined for various combinations of values, and the performance of the developed control chart is evaluated using the Average Run Length (ARE). Numerical examples are used to explain the proposed control chart, and simulated data is used to show how it might be used.

 

Cite:  T. Kavitha, M. Gunasekaran CONSTRUCTION OF A NEW ATTRIBUTE CONTROL CHART BASED ON RAYLEIGH DISTRIBUTION UNDER HYBRID CENSORING - A BAYESIAN APPROACH. Reliability: Theory & Applications. 2025, September 3(86):  981-989, DOI: https://doi.org/10.24412/1932-2321-2025-386-981-989


 

 

 

ENHANCING THE RELIABILITY OF THERMAL POWER SYSTEMS USING MEMBRANE-BASED WATER TREATMENT TECHOLOGIES

990-998

 

 

Ahmadova J.A.

 

 

 

The reliability and efficiency of thermal power plants (TPPs) are largely determined by the quality of water treatment systems that maintain a stable water-chemical regime (WCR) for boilers and auxiliary equipment. In scenarios where seawater with high salinity and variable composition is used as the primary water source, conventional treatment methods—such as ion exchange, chemical coagulation, and thermal desalination—prove inadequate and resource-intensive. This study investigates the application of a hybrid membrane-based configuration comprising ultrafiltration (UF), reverse osmosis (RO), and membrane distillation (MD). The proposed system enables the production of high-purity demineralized water, reduces operational risks, and lowers energy consumption through the utilization of low-grade waste heat. Based on pilot data and modeled performance, the UF-RO-MD cascade achieves up to 99% desalination efficiency with specific energy consumption in the range of 1.9-2.5 kWh/m3 and a significant reduction in scaling potential. A simplified case study is provided to illustrate the high effectiveness of membrane technologies in enhancing the sustainability and resilience of TPP operations, especially in coastal regions with limited freshwater availability. 

 

Cite:  Ahmadova J.A. ENHANCING THE RELIABILITY OF THERMAL POWER SYSTEMS USING MEMBRANE-BASED WATER TREATMENT TECHOLOGIES. Reliability: Theory & Applications. 2025, September 3(86):  990-998, DOI: https://doi.org/10.24412/1932-2321-2025-386-990-998


 

 

 

A NOVEL ENERGY-EFFICIENT APPROACH TO DETECT AND MITIGATE RPL ROUTING ATTACKS IN IOT NETWORK

999-1013

 

 

Deepak Upadhyay, Hiteishi Diwanji

 

 

 

Communication networks are constantly at risk from routing attacks, which have the potential to disrupt the network performance, information flow and jeopardize network integrity. Network resources and Energy consumption attacks on the Internet of Things (IoT) are the main targets to bring down the services of Internet of Things devices with attacks such as Denial of Service, Jamming etc. Node mobility results in frequent changes to network topology. This increases energy consumption and reduces node lifetimes, which can disrupt overall network functionality. To overcome these problems the author has proposed a hybrid and lightweight A Novel Energy-Efficient Approach to Detect and Mitigate RPL (EEADM-RPL) protocol considering control messages with route metrics in different detection and mitigation algorithm to mitigate the Blackhole attack, Rank attack and Sybil attacks under mobility environment at a time. An attack scenario created with the algorithms for all attacks using control messages and attributes of packets. The EEADM-RPL protocol uses basic RPL control messages, neighbor table, trust calculation, and a minimum rank hysteresis objective function to detect and eliminate the attacks. This protocol is suitable for industrial systems to handle cyber-attack and for the Vulnerability Assessment and Penetration Testing audit. The Cooja simulator, part of the Contiki operating system, simulates the attacks without mobility and with mobility demonstrates the effectiveness affecting the network and the resources. The outcomes of the simulation are compared with those of current protocols. According to the data, the proposed protocol demonstrates improvements over the conventional RPL protocols in several metrics: the average parent change ratio by 87.94%, the average packet loss ratio by 69.17%, end-to-end latency by 67.85%, and both energy consumption and end-to-end delay by 13.07%.

 

Cite:  Deepak Upadhyay, Hiteishi Diwanji A NOVEL ENERGY-EFFICIENT APPROACH TO DETECT AND MITIGATE RPL ROUTING ATTACKS IN IOT NETWORK. Reliability: Theory & Applications. 2025, September 3(86):  999-1013, DOI: https://doi.org/10.24412/1932-2321-2025-386-999-1013


 

 

 

EXPERT METHOD OF RANK PENALTIES

1014-1021

 

 

Alexander Bochkov, Nikolay Zhigirev, Alla Kuzminova

 

 

 

Voting methods include a variety of systems and technologies designed to facilitate the electoral process. These methods can range from the use of traditional paper ballots to modern electronic systems, each with unique features and functions. Heuristic peer review methods use simplified decision-making processes to evaluate complex scenarios, especially in areas such as usability and forecasting. These methods improve efficiency and accuracy by combining expert information with heuristic principles to improve results in a variety of applications. While heuristic methods offer significant advantages for expert evaluations, they can also lead to errors if not applied carefully, emphasizing the need for balanced approaches to complex evaluations. We propose an algorithm for finding the most consistent decision of experts in determining the leader in an alternative ranking problem.

 

Cite:  Alexander Bochkov, Nikolay Zhigirev, Alla Kuzminova EXPERT METHOD OF RANK PENALTIES. Reliability: Theory & Applications. 2025, September 3(86):  1014-1021, DOI: https://doi.org/10.24412/1932-2321-2025-386-1014-1021


 

 

 

SYSTEM RELIABILITY AND PROFITABILITY CONSIDERING CONCEPTS OF WARRANTY AND INSURANCE: AN OVERVIEW

1022-1039

 

 

Kajal Sachdeva, Gulshan Taneja, Amit Manocha

 

 

 

The concepts of reliability, warranty, and insurance are interwoven in certain respects. System warranties and insurance coverage, whether provided by the manufacturer or a third party, reflect the system's potential reliability and offer consumers a sense of security. Conversely, enhancing system reliability during the development process can help reduce warranty and insurance costs. The purpose of this study is to compile the existing literature and provide a structured review of system reliability evaluation, incorporating the concepts of warranty, pricing, and insurance policies. Synthesizes the ideas, models, and methodologies that various authors have included in their study. To achieve this, a detailed review of 111 journal articles published between 1992 and the present was conducted. The primary focus areas of the review include system reliability, warranty policies, insurance mechanisms, and cost analysis. In addition, the study highlights potential directions for future research in this domain. 

 

Cite:  Kajal Sachdeva, Gulshan Taneja, Amit Manocha SYSTEM RELIABILITY AND PROFITABILITY CONSIDERING CONCEPTS OF WARRANTY AND INSURANCE: AN OVERVIEW. Reliability: Theory & Applications. 2025, September 3(86):  1022-1039, DOI: https://doi.org/10.24412/1932-2321-2025-386-1022-1039


 

 

 

ATTRIBUTE CONTROL CHART BASED ON RAYLEIGH DISTRIBUTION: A BAYESIAN APPROACH 

1040-1053

 

 

M. Gunasekaran, T. Kavitha, S. M. Karthik

 

 

 

Statistical Process Control is a quality control approach that uses statistical tools to assess, monitor, and optimize processes. A control chart plays a crucial role in this method by tracking the performance of a process and providing a visual signal to detect any irregular deviations caused by specific assignable factors. It compares the values of a quality attribute against predetermined control limits. In typical quality control procedures, control charts are often created without considering parameter uncertainty. However, it is essential to identify any shifts in the parameters of the probability distribution linked to one or more variables associated with the process to ensure effective monitoring. Evaluating these parameters is vital, as it can influence the long-term functionality of the control chart in both controlled and uncontrolled environments. This article introduces an innovative attribute control chart that utilizes a Bayesian methodology based on the Rayleigh lifetime distribution, specifically applied under accelerated life testing with a hybrid censoring technique. The parameters for the control chart will be established through various combinations of values using a Bayesian approach, while the effectiveness of the control chart will be evaluated through the Average Run Length (ARL). Numerical examples will illustrate the proposed control chart, and simulated data will showcase its potential application. The effectiveness of the proposed control chart will be quantified through ARLs for different shift constants, sample sizes, and additional parameters such as p, Lower Control Limit, and Upper Control Limit. 

 

Cite:  M. Gunasekaran, T. Kavitha, S. M. Karthik ATTRIBUTE CONTROL CHART BASED ON RAYLEIGH DISTRIBUTION: A BAYESIAN APPROACH . Reliability: Theory & Applications. 2025, September 3(86):  1040-1053, DOI: https://doi.org/10.24412/1932-2321-2025-386-1040-1053