The purpose of this paper is to discuss the state of the art on models and methods for reliability optimization problems (ROPs) including reliability allocation, redundancy allocation and reliability-redundancy allocation. There are literally few surveys for reviewing the literature of the ROPs. Tillman et al. (1980) classified the related papers by system structure, problem type, and solution methods, separately. In another work, Tzafestas (1980) reviewed system reliability optimization models and the optimization techniques. Yearout (1986) reviewed the literature related to standby redundancy. Kuo (2000) studied the system reliability optimization based on system structure and solution methods. Kuo and Prasad (2004) overviewed system reliability optimization methods. Later, Kuo (2007) reviewed recent advances in optimal reliability allocation problems. The present study adds to the previous literature surveys and focuses mainly on papers after year 2000 but with a quick review on the previous works so that the readers become familiar with the existing approaches. This research investigates the literature from system structure, system performance, uncertainty state and solution approach standpoints, simultaneously.

This study aims to the rise in global economic integration is due to an expansion in volatility spillovers. Therefore, it is extraordinarily necessary to analyze the volatility spillovers for growing and developed international locations through the use of portfolio funding and danger management. This lookup investigates the Volatility Spillovers of Sharia Index on 6 ASEAN international locations all through the Covid-19 Pandemic the usage of the EGARCH model. Data have been received from 5 international locations with enormous volatility spillovers, particularly Indonesia, Malaysia, Singapore, Thailand, and Vietnam, to decide the reciprocal relationship of the inventory index in ASEAN as properly as the route of volatility movements. The result confirmed that this lookup is necessary for ASEAN traders besides for the Philippines. Furthermore, this lookup has sturdy sensible significance due to the fact the correct prediction of the volatility spillovers in worldwide fairness markets is quintessential for decreasing portfolio risk.

The present study endeavors to show an application of the multi objective optimization on the basis of ratio analysis (MOORA) method and technique for order performance by similarity to ideal solution (TOPSIS) method to select optimal process parameters in sheet hydroforming process. The right choice of the process parameters is critical to produce a final part with proper quality. In order to meet this characteristic, the important properties are the cup final thickness (FT), required forming force (FF) and radial stress (RS) at cup wall region. Nine alternatives for selecting the process parameters were taken into consideration based on Taguchi L9 orthogonal array. The limit drawing ratio (LDR), maximum pressure and prebulge pressure were selected as input variables. To solve the problem of process parameters’ selection, the two mentioned methods were used. A compromised weighting approach composed of Entropy and analytic hierarchy process (AHP) methods were used to weight all criteria. The alternatives ranking were performed using MOORA and TOPSIS methods and then the results were compared. The results achieved in both of the assessment represent that the alternative number 3, leads to the best multi performance features of the process among the 9 experiments. In this experiment LDR is 1.81, maximum pressure and prebulge pressure are 37 MPa and 15 MPa, respectively.

It is considered that determining the factors influencing the purchase intentions of customers in the field of social commerce by taking into account the cultural structures specific to each region can give highly valuable feedback to companies in the commercial field where competition has considerably increased. To this end, in the present study, it was aimed to propose and test out a structural model for the factors of social commerce constructs, social influence, habit and trust, which affect the purchase intentions of consumers. The study group of the research consisted of 447 Facebook users who live in North Cyprus. The scale form used as the data collection tool in the study consisted of 6 parts. In the first part of the scale, closed-ended questions were asked to determine the socio-demographic characteristics of the participants. The other parts of the scale consisted of 4 items about social commerce constructs, 4 items about habit, 3 items about social influence, 4 items about trust and 3 items about purchase intention. The reliability coefficients for the scales ranged between 0.79 and 0.92. These results indicated that the reliability coefficients were at the desired level. Socio-demographic variables were summarized using descriptive statistics, frequency and percentage distribution. First, normality test analyses were performed on the scales, and it was concluded that the data showed a normal distribution (kurtosis and skewness values varied between +2 / -2). Following the normality test, the measurement model was tested. Within the framework of a structural model proposed regarding the factors influencing the purchase intention of customers who shop through social commerce, it was concluded that habit, social influence and social commerce constructs had a significant effect on purchase intention. It was also concluded that habit and social commerce constructs significantly influenced purchase intention through trust.

In facing business competition in the manufacturing industry, it continues to adapt. Demands start from employees who are expected to continue to grow and leaders who are also changing. This is aimed at staying in business and also retaining the best employees by planning some changes in how to train and assign employees electronically as well as changing leadership styles to adapt to today's digital era. This study aims to determine the influence of E-learning, e-task and leadership style in the manufacturing industry in Indonesia. The data collection method in this study uses a questionnaire with 130 respondents. in this study using four variables, namely thirteen dimensions and twenty-six indicators. The analytical method used is descriptive analysis, and the test instrument uses SEM AMOS. The results showed that e-learning organization and e-task as well as leadership style had a significant and significant effect on Employee Engagement. the most factor great influence is the leadership style; This means that employees expect to get a new style in accordance with this digital era since there has been a change in the concept of employee engagement, where employees will feel they do not have a sense of engagement with the company if the attitude of the leader who is not sensitive to all aspects of changes in the effects of the digital era is caused by changes in employee behavior in this era where information is very easy to obtain for employees to know the conditions anywhere else that offers an advantage. compared to where they work now.

Recently, Symbiotic Organisms Search (SOS) algorithm is being used for solving complex problems of optimization. This paper proposes an Improved Symbiotic Organisms Search (I-SOS) algorithm for solving different complex unconstrained global optimization problems. In the improved algorithm, a random weighted reflective parameter and predation phase are suggested to enhance the performance of the algorithm. The performances of this algorithm are compared with the other state-of-the-art algorithms. The parametric study of the common control parameter has also been performed.

Inflation is an important factor influencing traditional economic order quality models. Marketing strategy depends on inflation due to public demand and availability of the materials. This paper presents an optimal inventory policy for deteriorating items using exponential demand rate under permissible delay in payments. Mathematical model has been derived under two cases: case I: cycle time is greater than or equal to permissible delay period, case II: cycle time is less than permissible delay period by considering holding cost as a function of time. Numerical examples and sensitivity analysis are given to reflect the numerical results. Mathematica software is used for finding optimal solutions.

The aim of this research is to identify the main determinants of Kosovo outbound tourists influencing the use of e-services in the hospitality industry. To test hypotheses, we used Partial Least Squares Path Modeling (PLS-PM). Findings suggest that the intention of Kosovo outbound tourists to use e-services in the hospitality industry is influenced positively by performance expectancy, facilitating conditions, perceived value, and satisfaction with information quality. We found that expected effort and social influence have no impact on the intention to use e-services. The relationship between users’ behavioral intentions and satisfaction with the information provided and real use behavior is confirmed. The perceived value depends on cost-savings, enjoyment and convenience from the use of e-services in hospitality.

This paper introduces a new comprehensive four-parameter distribution called the modified generalized linear failure rate (MGLFR) distribution. The method generalizes some well-known and most commonly used distributions in reliability such as exponential, Rayleigh, linear failure rate, generalized linear failure rate and modified Weibull distribution. The study also investigates some essential properties of this new distribution and considers the problem of the evaluation of system reliability by describing the lifetimes of components based on a fuzzy MGLFR distribution and by developing fuzzy reliability characteristics. The results can be applied to determine the reliability of real objects where parameters of lifetime variable are subject to uncertainty.

The selection of air compressor is a Multiple Criteria Decision Making (MCDM) problem including conflicting criteria and various alternatives. Selecting the appropriate air compressor is an important decision for the company as it affects the energy consumption and operating cost. To aid the decision making process in the companies, MCDM methods are proposed in the literature. In all MCDM methods, the main goal is to select the best alternative or to rank a set of given alternatives. In this paper, the air compressor is selected for a spinning mill of a textile company with an integrated approach based on MACBETH (Measuring Attractiveness by a Categorical Based Evaluation TecHnique) and COPRAS (COmplex PRoportional ASsessment) methods. MACBETH method is utilized to determine the weights of the criteria. Then COPRAS method is used to determine the ranking of the alternatives and select the best one.