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In this research work, the general form of reliability measures, which include availability, mean time to failure (MTTF), and sensitivity analysis, are investigated with their graphical representation, which would help designers and engineers improve the reliability of the system. Along with reliability assessment, a mathematical model is developed and solved to achieve the minimum cost of the system as well as maximum reliability.

In the proposed work, a general model of a solar seed sowing machine is considered for reliability evaluation using the Markov model process. The proposed system is a series-parallel arrangement of components where three components, namely the solar panel, batteries and direct current (DC) motor, are connected in series while all the operators are connected in parallel. The implemented Markov model approach assesses several parameters of reliability, which opens the scope for improvement in reliability and other measures like mean time to failure (MTTF) and sensitivity of the proposed system. So that the machine can deliver the desired output on the field. Also, the particle swarm optimization (PSO) algorithm is applied to optimize the cost of the system with the desired level of reliability.

Implementation of PSO provides the optimal cost for the proposed system with a predetermined level of reliability, which shows the relationship between reliability and cost of the system. Also, the Markov process approach provides the availability function, reliability function, reliability at different time values, MTTF and sensitivity of the proposed system.

This work evaluates the crucial characteristics of reliability for the proposed solar seed sowing machine using the Markov model which is a stochastic model. The assessment of reliability measures such as MTTF, availability and sensitivity plays a vital role in measuring and improving the performance of the machine in the actual environment. Examining the data obtained in this research is of great importance for the manufactures and system designers. Also, the powerful optimization technique PSO is implemented to solve a non-linear mixed-integer programming problem that provides the optimal cost for the system with desired reliability.

Ensuring safe operation of a urea fertilizer plant (UFP) is a vital aspect for its functioning and production. Clearly the safe operation of such systems can only be archived with proper and effective maintenance scheduling and through controlling its failures as well as repairs of the components. Also for this, the concern plant management must have the information regarding the failures that affects the system's performance most/least. The objective of this study is to analyze mathematically the factors that are responsible for the failure/degradation of the decomposition unit of UFP.

The considered system has been modeled by the aid of Markov's birth–death process with two types of failures for its components: variable (which are very similar in practical situations) and constant. The mathematical model is solved by the help of Laplace transform and supplementary variable technique.

In the present paper, the availability, reliability and mean time to failure (MTTF) are computed for the decomposition unit of the UFP. The critical components that affect the reliability and MTTF of the decomposition unit are identified through sensitivity analysis.

In this paper, a mathematical model based on the working of the decomposition unit of a UFP has been developed by considering two types of failure, namely, variable failures rates and constant failure rates (which has not been done in the literature for the decomposition unit). Conclusions in this paper are good references for the improvement of the same.

The purpose of this paper is to evaluate the reliability and signature reliability of solar panel k-out-of-n-multiplex system with the help of universal generating function.

Energy scarcity and global warming issues have become important concerns for humanity in recent decades. To solve these problems, various nations work for renewable energy sources (RESs), including sun, breeze, geothermal, wave, radioactive and biofuels. Solar energy is absorbed by solar panels, referred to as photovoltaic panels, which then transform it into electricity that can be used to power buildings or residences. Remote places can be supplied with electricity using these panels. Solar energy is often generated using a solar panel that is connected to an inverter for power supply. As a result, a converter reliability evaluation is frequently required. This paper presents a study on the reliability analysis of k-out-of-n systems with heterogeneous components. In this research, the universal generating function methodology is used to identify the reliability function and signature reliability of the solar array components. This method is commonly used to assess the tail signature and Barlow-Proschan index with independent and identically distributed components.

The Barlow-Proschan index, tail signature, signature, expected lifetime, expected cost and minimal signature of independent identically distributed are all computed.

This is the first study of solar panel k-out-of-n-multiplex systems to examine the signature reliability with the help of universal generating function techniques with various measures.

The purpose of this paper is to evaluate the reliability and structure function of refrigeration complex system consisted of four components in complex manner.

Although, a variety of methodologies have been used to assess the refrigeration system's reliability function that has proven to be effective, the universal generating function approach is the basis of this research study, which is used in the calculation of a domestic refrigeration system with four separate components that are related in series and parallel with a corresponding sample to form a complex machine.

In this paper, signature reliability of the refrigeration system has been evaluated with the universal generating function technique. There are four components present in the proposed system in complex (series and parallel) manner. The tail signature, signature, Barlow–Proschan index, expected lifetime and expected cost of independent identically distributed are all computed.

This is the first study of domestic refrigeration system to examine the signature reliability with the help of universal generating function techniques with various measures. Refrigeration systems are an essential process in industries and home applications as they perform cooling or the maintain temperature at the desired value. A cycle of refrigeration consists of four main components such as, heat exchange, compression and expansion with a refrigerant flowing through the units within the cycle.

The ideology of this article is to study the performance concerns of SDN Controllers, with the help of developed SRGM and thereby obtain its optimal testing duration. The effect of undetected uncertainty in the parameter values have also been catered in the proposal.

These uncertainties in the parameter values are studied as the risk of not meeting desired set of requirements, whose removal causes additional cost. Considering these two constructs as attributes of MAUT, the controller's optimal testing duration is obtained.

The article focuses towards obtaining the optimal duration for which the SDN Controllers must be tested. It was observed that the inculcation of risk-attribute has provided the higher utility value as compared to any other existing scenarios.

Plenty of SRGM have been proposed in the literature which talks about the testing stop time determination problems. But, none of them have considered the impact of risk of not meeting the requirements (reliability) along with cost to obtain its testing stop time. Further, validation of the proposed model in presented with the help of two releases versions of SDN controller platform, ONOS, entitled as “Kingfisher” and “Loon” and has acquired promising results.

The aim of the present work is to develop a method to find the preventive measures for COVID-19 and their priorities. These preventive measures are prioritized according to the expert opinion.

An integrated method using the Kano model and Fuzzy-AHP is used to achieve the study objectives. First, the preventive measures are identified according to the expert. Next, the Kano model is used to determine the different Kano categories for remedial activities that are identified by the World Health Organization (WHO) and other medical authorities. Finally, Fuzzy-AHP is applied to determine the weights of these activities and assign the priorities according to their impact.

It is observed that the activity Avoid Travelling is the most important classification or category with the highest weight as compared to the other activities and sub-activities. It is also noticed that the category packed food items get the lowest weight and is the least important classification or category. In this work, two different approaches, designed for different purposes, provide similar results and verify each other.

Research contributing to the classification and prioritization of preventive activities using Kano and Fuzzy-AHP methods is not available. In the critical time of COVID-19, when governments are obliged to deal with many infected patients and a high number of deaths, one can focus on different preventive activities according to their classification, weights and ranks.

The sustainable and circular growth of agro-produce is crucial in today's era. The current paper focuses on identifying the drivers which promote sustainability as well as circularity in the agro-produce supply chain and favor its implementation in agro-produce supply chain.

Drivers are identified by carrying out a brief literature review and then short-listed based on the expert's opinion. The crucial drivers identified are then categorized into four groups, i.e. farms, social, government and organization. A DEMATEL-DANP approach is used to analyze the relation among subfactors and factors by deriving network relations map. Further, the weights of each subfactor are measured followed by calculating the ranks of the drivers in significance with successful implementation of sustainable circular economy.

This study has applied DEMATEL-DANP approach to analyze the relationship among four factors and twelve sub factors and their contribution towards adopting the culture of sustainable circular economy in agro-produce supply chain. The results show that “Integration of farmers” and “Updated infrastructure and tools of the farm to promote diverse farming” are primary drivers for implementing SCE in APSC.

The research explored the domains of sustainability and circularity separately. Drivers that could accelerate the implementation of circularity in agro-produce in a sustainable manner were identified. This will help in designing sustainable circular model for working of the agro-produce supply chain.

This study aims to explore a paradigm for using servitization in circular supply chains, with research fields including smart, sustainable supply chains, circular economy, innovation, digital technology, product service systems and sustainability as focal areas.

A comprehensive statistical analysis of the literature on servitization, circular economy and smart supply chains reveals the history of the industry, including scholarly work, major concerns and future research prospects. The database for the analysis is provided by Scopus. Consequently, 288 research articles were reviewed, and the research trends of servitization, circular supply chains and smart supply chains from 2014 to 2022 (Q1) were covered.

The analysis reconnoitres bibliometric statistics highlighting notable authors, contemporary keywords for sifting through the literature, scientific dimensions related to smart supply chain, servitization and the circular economy, historical growth based on exploration trends and country-by-country investigation of the research field. The study also proposes a conceptual framework that illustrates how a greater emphasis on removing barriers to servitization could increase the efficiency of various circular supply chains. Given this, there is room for further research into the role servitization plays in ensuring long-term sustainability.

This paper helps to understand current scholarly publications on servitization, smart supply chains and their significance in the circular economy. It also provides a template to utilize the field’s prior accomplishments as a guide to future research opportunities.

This paper aims to find the best tools to influence the improvement of sustainability in food supply chains (FSCs) by conducting a systematic review of articles. The reader will learn how the different industry 4.0 tools (I4.0T) benefit the FSC and the limitations of each tool.

A review of 436 articles published during the period 2019 to 2022 referenced in the Scopus and Web of Science databases was performed. The review was limited to articles published in English and directly related to Industry 4.0, circular economy and sustainability in the food supply chain.

The results show different contributions of I4.0, with some being more influential than others in improving sustainability in FSCs; for example, Internet of Things and Blockchain have been shown to contribute more toward transparency, traceability, process optimization and waste reduction.

The paper's contribution consisted of ranking according to their importance and the I4.0T that affect sustainability in FSCs by classifying the aspects of each tool and the sustainability factors through a categorization by the Analysis Hierarchy Process.

Present work deals with the partial substitution of cement by waste demolished concrete powder (WDP) for reducing the carbon footprints of concrete.

Control specimens and the specimens with 20% WDP as fractional substitute of cement were prepared. The waste powder was thermally activated at 825 °C prior to its use in the mix. The prepared specimens were evaluated in terms of density, workability, mechanical strength, Ultrasonic pulse velocity (UPV) and rebound hammer (RH).

The results showed that with the substitution, the workability of the mix increased, while the density decreased. A decrement within a 20% limit was found in compressive strength. The UPV and RH results were closely linked to the other results as mentioned above.

The study deals with only M15 concrete and the substitution level of only 20% as a baseline.

The concrete containing 20% WDP is lightweight and more workable. Moreover, its strength at 28 days is 14 MPa, only 1 MPa lesser than the characteristic strength.

The WDP can be recycled and the dumping in landfills can be reduced. This is an important effort towards the decarbonation of concrete.

Previous literature indicates that the WDP has been frequently used as a partial replacement of aggregates. However, some traces of secondary hydration were also reported. This work considers the effect of partial substitution of cement by the WDP.