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The purpose of this paper is to control flow separation over a NACA 4415 airfoil by applying unsteady forces to the separated shear layers using dielectric barrier discharge (DBD) plasma actuators. This novel flow control method is studied under conditions which the airfoil angle of attack is 18°, and Reynolds number based on chord length is 5.5 × 10⁵.

Large eddy simulation of the turbulent flow is used to capture vortical structures through the airfoil wake. Power spectral density analysis of the baseline flow indicates dominant natural frequencies associated with “shear layer mode” and “wake mode.” The wake mode frequency is used simultaneously to excite separated shear layers at both the upper surface and the trailing edge of the airfoil (dual-position excitation), and it is also used singly to excite the upper surface shear layer (single-position excitation).

Based on the results, actuations manipulate the shear layers instabilities and change the wake patterns considerably. It is revealed that in the single-position excitation case, the vortices shed from the upper surface shear layer are more coherent than the dual-position excitation case. The maximum value of lift coefficient and lift-to-drag ratio is achieved, respectively, by single-position excitation as well as dual-position excitation.

The paper contributes to the understanding and progress of DBD plasma actuators for flow control applications. Further, this research could be a beneficial solution for the promising design of advanced low speed flying vehicles.

Some essential issues about modeling of reverse logistics (RL) systems and product recovery networks include consideration of the qualities of the returned products, taking into account uncertainty and integrating the forward and reverse flows. The purpose of this paper is to develop the integrated RL model, which focuses on the control of inventory and production planning problems in a case of uncertainty in demand, quantities and qualities of returns.

The model involves a forward production route, three alternative recovery routes and a disposal route. Various levels of qualities are considered for returned products. A fuzzy mixed integer programming model (FMIP) is developed to provide a solution for the problems of production planning and inventory control. After maximizing the satisfaction degree, different solutions can have the same maximum. Moreover, policies that use all recovery routes and reduce the overall uncertainty have no chance to be chosen. To tackle these problems, a two-phase approach method is applied.

According to the results of the numerical example, using different and appropriate recovery options based on the quality of returns can significantly decrease the recovery costs. Similarly, it is shown that the two-phase approach can be an effective and efficient method to reach a satisfactory solution for such problems.

In this study, after maximizing the FMIP model, a two-phase approach ‒ as a novel optimization technique in this research ‒ is employed to achieve a desirable solution.

The purpose of this paper is to evaluate the effect of CRM performance and technological innovation on performance of media entrepreneurs considering firm size.

This is an analytical study used to empirically test the hypotheses proposed for SEM techniques using PLS and R packages. It used two steps in this way: the assessment of the outer model and the assessment of the inner model. Moreover, a bootstrapping method was employed to test indirect effects. Data were collected by distributing 127 questionnaires between the managers and deputies of active firms across Rasht, Iran.

The effect of CRM performance on SMEs performance development is partially mediated by media entrepreneurship. Moreover, the effect of technological innovation on SMEs performance development is mediated by media entrepreneurship. Furthermore, permutation test results indicated that there is no significant difference between small- and medium-sized firms.

This study used cross-sectional sampling method that can seriously limit result generalization. Therefore, conducting longitudinal studies is strongly recommended.

The results of IPMA matrix indicated the serious importance of technological innovation, as a variable with the highest importance for SMEs performance development. Nevertheless, this variable has received the lowest importance in the studied population. Therefore, SMEs’ managers should pay sufficient attention to the concepts of “product innovations” and “process innovations.”

This study is of high importance in that it has adopted new and effective indices for statistical analysis. IPMA matrix, permutation test, CTA and FIMIX are examples. In addition, plspm and Matrixpls packages in R were used for the first time in this study.

This study uses a phenomenology method to investigate the experiences of married Muslim women while having romantic conversations via online dating sites during the COVID-19 pandemic. Sixteen participants were selected via purposive sampling, and the data were gathered through semi-structured interviews. The results confirm that resistance to Islamic marriage limitations is the underlying reason accounting for Muslim women's romantic chat. However, “premarital experiences in virtual space” and “chat as a remedy for loneliness” create the causal conditions of romantic chat, and “experience of family restrictions” and a “sense of freedom” provides the foundation for an online romantic chat. It is worth noting that those who voice a sense of “unhappy marriage” and “husband's sexual coldness” are more likely to turn to sex chat during the COVID-19 pandemic. The consequences of digital romantic conversations for married Muslim women are “chat addiction” and “feeling a sense of betrayal.”

The purpose of this study is to assess the effect of process quality management (PQM) activities on firm's operational performance (OP) through the mediation of firm's absorptive capacity (AC).

This research builds on the theory of knowledge-based view to conduct a survey of 294 manufacturing companies in India. With the use of Hayes' PROCESS Macro in SPSS, the collected data were used to analyze the proposed mediating effect of firm's AC and moderating effects of leadership commitment (LC).

Study results suggest that both PQM and firm's AC contribute to improved OP and should be promoted. The firm's AC was found to partially mediate the impact of PQM on the firm's OP. Results also show that improved firm's AC can have a substantial effect on improvement in OP by stronger support of LC.

The results may lack generalizability due to the selected cross-sectional nature of the current study. Researchers are also encouraged to further test the proposed ideas using a longitudinal design approach.

To translate PQM initiatives into core strategic competencies, manufacturing firms need to develop their AC. Senior managers in the manufacturing sector should concentrate strongly on developing a knowledge-driven working culture to enhance operational efficiency and manufacturing productivity.

Current research study can be considered as one of the very few empirical analyses that investigated the mediating impact of the firm's AC on the PQM-firm's OP relationship. In the operations management (OM) literature, the investigation of the moderating effect of LC on the mediation of the firm's AC between the PQM and OP metrics can be considered to be a noteworthy theoretical addition.

This study aims to test the asymmetric impact of institutional ownership on firm performance. This study does it through an examination of the hypotheses of efficient monitoring and convergence of interests from the Tehran Stock Exchange (TSE).

Using a panel smooth transition regression model, as a new econometric technique, this paper examined the data to explore the asymmetric impact of institutional ownership on firm performance. With regard to 177 firms for the period 2009 to 2018 from TSE. Performance proxies are returned on asset (ROA), return on equity (ROE) and Tobins’ Q.

The empirical for three performance proxies results strongly rejected the null hypothesis of linearity and the test for no remaining nonlinearity indicated a model with one transition function and one threshold parameters. The first regime (levels of institutional ownership below 28.5% and 43.5% for ROA and Tobins’ Q) showed that performance increases with institutional ownership while the trend was reversed in the second regime (levels of institutional ownership above 28.5% and 43.5% for ROA and Tobins’ Q percent). Also, institutional shareholders percent between 4.2 and 14.1 explain the positive relationship between institutional shareholders and ROE.

Furthermore, the findings of this study suggest that the application of institutional ownership theories calls for more inquiry.

This paper aims to propose a stepwise method to improve the sustainability of manufacturing processes.

The proposed approach is based on an extensive literature review and research around the environmental, economic and social pillars of sustainability in manufacturing firms. Considering the lean approach, the manufacturing processes are mapped in a value stream and analyzed through the extensive identified sustainability criteria.

The findings reveal the consumption and waste of natural and nonrenewable resources, through going beyond the existing boundaries and focusing on relevant derived production pieces and tracing to their origins. The findings also present the effect of the time value of money on sustainability by using the cost–time profile as a sustainability criterion. This research finds out the employees’ impacts on sustainability improvement through an effective focus on technical, cultural and personal aspects.

The research outcomes provide operations managers and decision-makers in the field of sustainability with a practical platform to comprehend and assess the factors contributing to the manufacturing process sustainability and to plan relevant corrective actions accordingly.

The extended view of sustainability criteria in this research as well as its visual-analytical approach will help practitioners to assess and improve sustainability in their operations in a more holistic way.

One of the issues currently being discussed around the globe, and especially in the tourism industry, is revisit intention. This study uses a bibliometric analysis strategy based on the Web of Science (WOS) database to examine the literature on revisit intention.

In this study, a sample of 482 articles was analyzed. The R programming language was used to process the data and graph the results.

The results found the occurrence of publications by year, publication source information and authors, journals, countries, institutions, thematic maps, current trends of topics in hospitality and tourism toward revisiting intention, and the most cited papers in revisit intention. This study highlights the importance of revisiting intention in the hospitality and tourism industry. The bibliometric analysis helps to set the research agenda on revisit intention.

To the best of the authors’ knowledge, this is the first study of its kind to present an empirical evaluation of revisit intention using inclusive mapping.

This study is primarily aimed at investigating the asymmetric impact of institutional ownership on the relationship between stock liquidity and stock return. It was conducted by testing the hypotheses regarding efficient monitoring and adverse selection from Tehran Stock Exchange (TSE).

Using a panel smooth transition regression model and selecting 183 firms for the period from 2009 to 2019 from TSE, this study examined the data to explore the asymmetric impact of institutional ownership on the relationship between stock liquidity and stock return.

The results show a positive impact by institutional ownership on the relationship between stock liquidity and stock return in the first regime (threshold level 39%), whereas in the second regime, there is a negative impact by institutional ownership on the relationship between stock liquidity and stock return. Furthermore, the firms were divided into two groups based on the market value. The first group includes those with a market share less than the mean total market value of the sample. The second group includes firms with a market share higher than the mean total market value of the sample (large firms). The results illustrate that the threshold level is 32% and 44% for the first and second groups, respectively.

The findings of this study suggest that institutional ownership theories require closer inquiry.

Students’ academic achievement is a multifaceted phenomenon. While depression can suppress academic performance, academic satisfaction can promote it. This study aims to investigate the relationship between depression and academic satisfaction among students studying at Shahroud University of Medical Sciences.

This cross-sectional study was carried out on 312 undergraduate students of Shahroud University of Medical Sciences. Data collection tools included demographic data form, University Student Depression Inventory and academic satisfaction scale. Data were collected by a simple random sampling method and self-reporting by the participants. Data were analyzed using descriptive and inferential statistics (multivariate multiple regression analysis and multivariate linear regression).

The participants’ mean depression and academic satisfaction scores were 71.92 ± 22.94 and 53.70 ± 9.69, respectively. In addition, the depression score was significantly and inversely correlated with students' academic satisfaction (r = −0.122, p-value = 0.031). Moreover, there was a significant correlation between students’ depression with marital status, level of the semester, interest in the field of study and study topic.

This study emphasizes improving education, spiritual and social support and strengthens strategies to deal with depression and medical science students’ related factors.

Students of medical sciences are exposed to depression during their college years, which is related to their academic satisfaction.