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This paper aims to improve the computational efficiency of higher-order accurate Noye–Hayman [NH (9,9)] implicit finite difference scheme for the solution of electromagnetic scattering problems in tunnel environments.

The proposed method consists of two major steps: First, the higher-order NH (9,9) scheme is numerically discretized using the finite-difference method. The second step is to use an algorithm based on hierarchical interpolative factorization (HIF) to accelerate the solution of this scheme.

It is observed that the simulation results obtained from the numerical tests illustrate very high accuracy of the NH (9,9) method in typical tunnel environments. HIF algorithm makes the NH (9,9) method computationally efficient for two-dimensional (2D) or three-dimensional (3D) problems. The proposed method could help in reducing the computational cost of the NH (9,9) method very close to O(n) usual O(n3) for a full matrix.

For simplicity, in this study, perfect electric conductor boundary conditions are considered. Future research may also include the utilization of meteorological techniques, including the effects of backward traveling waves, and make comparisons with the experimental data.

This study is directly applicable to typical problems in the field of tunnel propagation modeling for both national commercial and military applications.

The purpose of this paper is to provide a brief introduction of the finite difference based parabolic equation (PE) modeling to the advanced engineering students and academic researchers.

A three-dimensional parabolic equation (3DPE) model is developed from the ground up for modeling wave propagation in the tunnel via a rectangular waveguide structure. A discussion of vector wave equations from Maxwell’s equations followed by the paraxial approximations and finite difference implementation is presented for the beginners. The obtained simulation results are compared with the analytical solution.

It is shown that the alternating direction implicit finite difference method (FDM) is more efficient in terms of accuracy, computational time and memory than the explicit FDM. The reader interested in maximum details of individual contributions such as the latest achievements in PE modeling until 2021, basic PE derivation, PE formulation’s approximations, finite difference discretization and implementation of 3DPE, can learn from this paper.

For the purpose of this paper, a simple 3DPE formulation is presented. For simplicity, a rectangular waveguide structure is discretized with the finite difference approach as a design problem. Future work could use the PE based FDM to study the possibility of utilization of meteorological techniques, including the effects of backward traveling waves as well as making comparisons with the experimental data.

The proposed work is directly applicable to typical problems in the field of tunnel propagation modeling for both national commercial and military applications.

There are various types of film libraries. The majority exist to serve the needs of a parent organization—either a producing company, a Government department, or a television authority. Including the national libraries, who are concerned primarily with the preservation of their material, all are prepared to supply material to outside film‐making organizations subject to certain conditions. All, too, are concerned with the lending or distribution of show copies.

This study investigates the mechanism between work-family conflict (WFC) and job dissatisfaction by considering threat to family role as a mediator and role segment enhancement as a moderator.

The data were collected from 245 male and 245 female police officers using a questionnaire-based survey method through convenience sampling.

Results revealed that threat to family role partially mediates the association between WFC and job dissatisfaction. Role segment enhancement was also noted to weaken the association between WFC and job dissatisfaction. Moreover, the study revealed that male employees are more likely to draw a boundary between their work and family domain, which was not found in their female counterparts.

The survey for this study was conducted in a male-dominant developing country, so results may be different in developed countries. The study has theoretical and managerial implications.

This study adds value to the existing literature on work-family conflicts in the perspective of source attribution and boundary management. Further, to the best of researchers' knowledge, none of the previous studies have examined role segment enhancement and threat to family role among the police workforce.

This study aims to investigate the question concerning whether tournament incentives motivate chief executive officers (CEOs) to be socially responsible.

Data from all A-share Chinese companies listed on the Shanghai and Shenzhen stock exchanges for the period from 2010 to 2015 are used. To draw inferences from the data, ordinary least squares (OLS) regression and cluster OLS are used as a baseline methodology. To control for the possible issue of endogeneity, firm-fixed-effects regression, two-stage least squares regression and propensity score matching are used.

A reliable evidence is found that tournament incentives motivate CEOs to be more socially responsible. Additional analysis reveals that the positive effect of CEO tournament incentives on corporate social responsibility performance (CSRP) is more pronounced in state-owned firms than it is in non-state-owned firms. The study’s findings are consistent with tournament theory and the conventional wisdom hypothesis, which proposes that better incentives lead to competitiveness, which improves financial and social performance.

The study’s findings have implications for companies and regulators who wish to enhance CSRP by giving tournament incentives to top managers. Investment in social responsibility may reduce the conflict between executives and employees and improve the corporate culture.

This study contributes to the existing literature by providing the first evidence that CEOs’ tournament incentives play a vital role in CSRP. The study’s findings contribute to tournament theory.

The purpose of this paper is to investigate how employees’ Islamic work ethic might enhance their propensity to help their coworkers on a voluntary basis, as well as how this relationship might be invigorated by despotic leadership. It also considers how the invigorating role of despotic leadership might depend on employees’ gender.

Survey data were collected from employees and their supervisors in Pakistani organizations.

Islamic work values relate positively to helping behaviors, and this relationship is stronger when employees experience despotic leadership, because their values motivate them to protect their colleagues against the hardships created by such leadership. This triggering role of despotic leadership is particularly strong among female employees.

For organizations, the results demonstrate that Islamic work values may be important for creating a culture that promotes collegiality, to a greater extent when employees believe that their leaders act as despots who exploit their followers for personal gain.

This study elaborates how employees’ Islamic work ethic influences the likelihood that they help their coworkers, particularly in work contexts marked by stress-inducing leadership.

This paper aims to address essential questions regarding social entrepreneurial intentions. Do traits such as perceived social impact, social worth and social network influence, social entrepreneurial intentions among the young populous generation of Pakistan? To get a deeper insight, this paper further raises questions regarding the relationship of these predictors and social entrepreneurial intentions with empathy which is considered as a key determinant and a distinguishing trait to become a social entrepreneur.

This paper involves a quantitative research design using a partial least square structural equation modeling approach to measure the effects of the structural model. For this, a cross-sectional survey was conducted with a purposive sample of 247 university students from Pakistan.

Results showed a positive relationship between antecedents and social entrepreneurial intentions. Overall analysis exhibited social worth as a dominant trait and social network as the least influencing trait to impact social entrepreneurial intentions.

It will help micro and macro-level policymakers including government officials and NGOs and educators to create awareness and provide support and encouragement to individuals who aim to initiate social enterprise.

The present study makes significant contributions to the social entrepreneurship literature, as it is one of the first academic studies on social entrepreneurial intentions in Pakistan. This paper enriches the theoretical foundation by assessing the influence of perceived social impact, social worth and social network on social entrepreneurial intentions. Also, the relationship of Empathy with each of these antecedents is examined for the first time in the social entrepreneurial intentions context which is a valuable contribution both theoretically and practically.

Using the conservation of resources (COR) theory, the present study aims to examine the role of participative leadership in frontline service employees (FLEs)’ service recovery performance. The present study also tests FLEs’ role breadth self-efficacy (RBSE) as a theoretically relevant mediator and FLE trait mindfulness as an important moderator.

Data were collected using time-lagged (three rounds, two weeks apart) from two sources (193 FLEs and 772 customers, who experienced a service failure). Structural equation modeling (Mplus, 8.6) was employed to analyze the data.

The results revealed that participative leadership was positively associated with FLEs service recovery performance, both directly and indirectly, via RBSE. The results also showed that FLE trait mindfulness moderated the link of participative leadership with RBSE and the indirect association of participative leadership with service recovery performance, via RBSE.

This study suggests that organizational leaders who exhibit participative leadership behavior are valuable for organizations. By demonstrating such behaviors, they boost FLEs' RBSE, which in turn improves their service recovery performance.

The present work makes important contributions to the literature on service recovery performance by foregrounding two important yet overlooked antecedents (participative leadership and RBSE) of FLE service recovery performance. The present work also contributes to the nascent literature on the antecedents and outcomes of RBSE in service contexts.

Winglets play a major role in saving fuel costs because they reduce the lift-induced drag formed at the wingtips. The purpose of this paper is to obtain the best orientation of the winglet for the Office National d’Etudes et de Recherches Aérospatiales (ONERA) M6 wing at Mach number 0.84 in terms of lift to drag ratio.

A computational fluid dynamics analysis of the wing-winglet configuration based on the ONERA M6 airfoil on drag reduction for different attack angles at Mach 0.84 was performed using analysis of systems Fluent. First, the best values of cant and sweep angles in terms of aerodynamic performance were selected by performing simulations. The analysis included cant angle values of 30°, 40°, 45°, 55°, 60°, 70° and 75°, while for the sweep angles 35°, 45°, 55°, 65° and 75° angles were used. The aerodynamic performance was measured in terms of the obtained lift to drag ratios.

The results showed that slight alternations in the winglet configuration can improve aerodynamic performance for various attack angles. The best lift to drag ratio for the winglet was achieved at a cant angle of 30° and a sweep angle of 65°, which caused a 5.33% increase in the lift to drag ratio. The toe-out angle winglets as compared to the toe-in angles caused the lift to drag ratio to increase because of more attached flow at its surface. The maximum value of the lift to drag ratio was obtained with a toe-out angle (−5°) at an angle of attack 3° which was 2.53% greater than the zero-toed angle winglet.

This work is relatively unique because the cant, sweep and toe angles were analyzed altogether and led to a significant reduction in drag as compared to wing without winglet. The wing model was compared with the results provided by National Aeronautics and Space Administration so this validated the simulation for different wing-winglet configurations.

This study aims to review relevant studies concerning consumer purchase of halal-certified products. A total of 35 studies related to the consumer purchasing behavior of halal-certified products in top-tier journals have been identified according to the recommended systematic literature review methodology.

A systematic literature review approach was implemented to examine, summarize and finally interpret the relevant research stream pertaining to consumer purchase of halal-certified products.

There are five research streams extracted from this systematic review, halal study context, theories adapted, covariance-based-structural equation modeling (SEM) vs partial least square-SEM, Muslim vs nonMuslim consumer and role of religiosity. Despite the growing interest in the quantitative approach in consumer purchase behavior in halal-certified products, scholars in halal consumer studies must have a greater extent of work. These include incorporating diverse theories in the framework, an advanced SEM approach, and relevant determinants to capture consumer purchasing of halal-certified products in the highly anticipated and profitable Muslim market.

Findings would help researchers in halal studies to consider and contemplate critical issues, according to the research stream presented in this review.

To the best of the authors’ knowledge, this study is the first review of quantitative studies on consumer purchases of halal-certified products.