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Reliability-based design optimizations (RBDOs) of engineering structures involve complex non-linear/non-differentiable performance functions, including both continuous and discrete variables. The gradient-based RBDO algorithms are less than satisfactory for these cases. The simulation-based approaches could also be computationally inefficient, especially when the double-loop strategy is used. This paper aims to present a pseudo-double loop flexible RBDO, which is efficient for solving problems, including both discrete/continuous variables.

The method is based on the hybrid improved binary bat algorithm (BBA) and weighed simulation method (WSM). According to this method, each BBA’s movement generates proper candidate solutions, and subsequently, WSM evaluates the reliability levels for design candidates to conduct swarm in a low-cost safe-region.

The accuracy of the proposed enhanced BBA and also the hybrid WSM-BBA are examined for ten benchmark deterministic optimizations and also four RBDO problems of truss structures, respectively. The solved examples reveal computational efficiency and superiority of the method to conventional RBDO approaches for solving complex problems including discrete variables.

Unlike other RBDO approaches, the proposed method is such organized that only one simulation run suffices during the optimization process. The flexibility future of the proposed RBDO framework enables a designer to present multi-level design solutions for different arrangements of the problem by using the results of the only one simulation for WSM, which is very helpful to decrease computational burden of the RBDO. In addition, a new suitable transfer function that enhanced convergence rate and search ability of the original BBA is introduced.

Generally, iterative methods which have some instability solutions in complex structural and non-linear mechanical problems are used to compute reliability index. The purpose of this paper is to establish a non-linear conjugate gradient (NCG) optimization algorithm to overcome instability solution of the Hasofer-Lind and Rackwitz-Fiessler (HL-RF) method in first-order reliability analysis. The NCG algorithms such as the Conjugate-Descent (CD) and the Liu-Storey (LS) are used for determining the safety index. An algorithm is found based on the new line search in the reliability analysis.

In the proposed line search for calculating the safety index, search direction is computed by using the conjugate gradient approach and the HL-RF method based on the new and pervious gradient vector of the reliability function. A simple step size is presented for the line search in the proposed algorithm, which is formulated by the Wolfe conditions based on the new and previous safety index results in the reliability analysis.

From the current work, it is concluded that the proposed NCG algorithm has more efficient, robust and appropriate convergence in comparison with the HL-RF method. The proposed methods can eliminate numerical instabilities of the HL-RF iterative algorithm in highly non-linear performance function and complicated structural limit state function. The NGC optimization is applicable to reliability analysis and it is correctly converged on the reliability index. In the NCG method, the CD algorithm is slightly more efficient than the LS algorithm.

This paper usefully shows how the HL-RF algorithm and the NCG scheme are formulated in first-order reliability analysis. The proposed algorithm is validated from six numerical and structural examples taken from the literature. The HL-RF method is not converged on several non-linear mathematic and complex structural examples, while the two proposed conjugate gradient methods are appropriately converged for all examples. The CD algorithm is converged about twice faster than the LS algorithm in most of the problems. Therefore, application of the NCG method is possible in reliability analysis.

The purpose of this research is to assess how full-time tenured academic staff promotion practices (SPP) in Malaysian private universities (MPUs) influence academic staff engagement (SE) and academic staff performance (SP).

The research used quantitative and descriptive methods, focusing on MPUs' academic staff as the unit of analysis. Sampling involved simple random and stratified techniques, with 314 academic personnel surveyed. Participant data was collected through a questionnaire, and study hypotheses were tested using partial least squares structural equation modeling (PLS-SEM) via a bootstrapping approach.

The findings show that SE somewhat mediates the connection between SPP and SP and that SPP significantly influences SP.

This study emphasizes the importance of impartiality and transparency within university administration when promoting academic staff. Universities should adopt modern strategies and approaches for advancing their employees to higher positions, doing so will motivate employees to fully invest in their work, leading to sustained high-performance levels.

This research has substantially improved the understanding and the practical utilization of literature about SP, SPP and SE. This improvement can potentially facilitate the development of models, theories, research initiatives, and practical strategies geared toward enhancing staff efficiency.

Learning as the way in which labor acquire new knowledge and skills has important strategic implications for the competitive advantage of an organization. The purpose of this paper is to present an agent-based modeling (ABM) approach to investigate the learning behavior of workers. The effect of interactions among different workers as well as the factors affecting the workers’ learning behavior is assessed using the proposed ABM approach.

For this purpose, the processes through which the competency value of worker is changed are understood and the workers’ learning behavior is modeled, taking account of various influencing factors such as knowledge flow, social ability to teach and forgetting factor.

The proposed model is implemented on a real steel structure project to evaluate its applicability and performance. The variation in the competency value of different workers involved in the project is simulated over time taking account of all the influencing factors using the proposed ABM approach.

In order to assess the effect of interactions among welders as well as the welders’ characteristics on their learning behavior, the competence value of different welders is evaluated.

This research presents an ABM approach to investigate the workers’ learning behavior. To evaluate the performance of the proposed ABM approach, it was implemented on a real steel structure project. The learning behavior of different welders (agents) was simulated taking account of their interactions as well as the factors affecting the welders’ learning behavior. The project involved the welding of a 240-ton steel structure. The initial project duration was estimated as 100 days. In this project, it has been planned to execute the welding process using three different welders namely welder A, B and C.

The purpose of the study has been to fill the gap detected in the literature and to analyze whether the application of management of R&D in accordance with UNE 166002:2021 allows companies to obtain higher product innovation and better performance, specifically incremental and radical product innovations.

The population used in this study included Spanish manufacturing organizations that were active, had more than 50 employees according to the SABI. The information was collected through a structured questionnaire previously tested using a company specializing in the sector under the supervision of the authors. A total of 1,154 companies were randomly contacted in order to reach an acceptable number of 225 valid questionnaires. The data analysis has been carried out with structural equation methodology.

The results obtained with a sample of 225 companies show that the application of this standard for innovation management promotes the development of new products with incremental and radical changes, and improves business performance. It has also been found that incremental and radical product innovations mediate the relationship between this standard and performance.

Firstly, the survey is only addressed to the company's operations manager. Secondly, the sample used is cross-sectional, whereas innovation management implies a broad implementation process.

Managers must know that radical and incremental product innovation can improve the company's operational performance. And the most direct implication of this work is that, those companies that are committed to the development of innovations should seriously consider the application of the principles incorporated in Standard 166,002, as an instrument that improves the results of innovation in the organization. Since this SIMS promotes both types of innovations, it improves results directly and indirectly through these product innovations.

The existing literature indicates that no empirical study has focused on the benefits of this SIMSs for innovation and BP. This paper fills this gap detected in the literature and analyzes the results of the implementation of this standard on incremental and radical product innovations and business performance.

The purpose of this research is to investigate the relationships among Syrian consumers’ information motivation and beliefs about and attitude towards Web advertising.

A cross-sectional investigation is conducted and the proposed model is tested and revised using structural equation modeling technique.

The results indicate that information motivation predicts three dimensions of beliefs about Web advertising, i.e. positively for information and entertainment; and negatively for irritation. It is found also that information motivation positively influences consumers’ attitudes towards advertising. As well as, information, entertainment and irritation are found to partially mediate the relationship between information motivation and attitude towards Web advertising. Additionally, values corruption is found to negatively influence Syrian consumers’ attitudes toward Web advertising.

Researchers are advised to use the validated scales in the present study when it comes to measure beliefs about and attitudes toward Internet advertising in the Syrian context or other Arab countries contexts. Also, further investigations using longitudinal design are needed to check the validity of our results on a longer period of time, besides using qualitative methods along with quantitative analyses could produce a wider vision to the results. Additionally, it is recommended that other types of Internet usage motivation are included in future studies’ models.

Advertisers promoting in Syria are encouraged to influence Syrian consumers’ attitudes towards Web advertising to be more positive and less negative through offering free and high-quality content of information, especially for Internet users with high levels of informative motivation. Additionally, producing informative, enjoyable, less annoying and less values corruptive could help promoting for favorable attitudes towards Web advertising.

This research comes to be one of the first studies to investigate Syrian consumers’ beliefs about and attitudes towards Internet advertising. Also, this study provides evidence of the direct relationship between information motivation and general attitudes towards Web advertising.

This study aims to investigate the possible effect of Citrus latifolia (CL) extract on biomarkers of oxidative stress, including lipid peroxidation products in rats fed a high cholesterol diet

Hypercholesterolemia was induced by feeding normocholesterolemic rats 1 per cent cholesterol-enriched diet for 15 days. An experimental group (n = 20) was divided into two groups (n = 10) and fed the same diet with or without CL lyophilized aqueous extract (1 per cent) for four weeks. At day 28, ten rats from each group were killed.

Treatment with CL lyophilized aqueous extract compared with the untreated group had decreased plasma total cholesterol (TC) (−36 per cent), triacylglycerols (−48 per cent), isoprostanes values (−74 per cent) and reduced thiobarbituric acid reactive substances in erythrocytes (−21 per cent). However, the supplementation of CL peels in the hypercholesterolemic diet enhanced superoxide dismutase (+69 per cent), glutathione reductase (+30 per cent) and catalase activities (+34 per cent).

In hypercholesterolemic rats, administering CL extract ameliorates dyslipidemia and attenuates lipid peroxidation in tissues. These results suggest that CL could be beneficial in the primary treatment of hypercholesterolemia and oxidative damage caused by a high-cholesterol diet.

The purpose of this study is to determine the impact of job security on doctors’ retention, with job satisfaction and job embeddedness as the mediators. In doing so, the authors seek to contribute to the existing literature by providing additional empirical evidence on the links between job security, job satisfaction, job embeddedness and employee retention by using social exchange theory.

An empirical study was conducted on doctors working in public hospitals in Pakistan. Data from selected public hospitals were collected using semi-structured questionnaires. The simple random sampling method was applied for participant selection and partial least squares-structural equation modelling was used for data analysis purposes.

The findings confirmed the direct and mediation relationships. Thus, all of this study’s hypotheses are supported. The results indicate that job security can improve doctors’ retention. Further, job satisfaction and job embeddedness play crucial roles in mediating the direct relationship.

This study elaborates job security in health-care sector of Pakistan and also provides empirical evidence of the antecedents and mediators of doctors’ intention to continue working in the health-care industry.

Since the election of June 2009, the Islamic Republic of Iran has witnessed a huge crisis with the outburst of street protests and demonstrations, challenging its validity. Indeed, it has been so intense that it has shaken the whole Islamic Republic for the first time since the 1979 Iranian revolution. What has happened since the disputed election was an upheaval few had anticipated, an opening of Pandora's box, with millions daring to question the, Velayate Fagih, the most important constituent of the Islamic Republic. This postelection period has created a “revolutionary”’ potential that has so far been met with repressive force and violence on the part of the ruling elites leaving no leverage for compromise. Of course, in the 30 years since the revolution, the Islamic Republic's power structures have faced factionalism. These recent developments demonstrate how deeply rooted run the contradictions and differences between the various groups. This upheaval has thrown all sorts of questions into the air: could Iran remain as a Republic? Or would Iran turn into a God's Kingdom, ever more dictatorial in its approach? Or would the splits within the ruling elites continue to crack the fabric of the regime? Will there be a similar schism to that which took place during the Constitutional Revolution in the early 20th century when a leading member of the clergy, Noori, was finally hanged in July 1909 for being openly against reform? Finally, what is the possibility of change beyond the Islamic Republic in Iran?

Drawing on expectancy violation theory, this study aims to assess the impact of corporate environmental irresponsibility (CEI) on workplace deviant behaviors (WDB) of Generation Z and Millennials through the mediation of moral outrage.

The data were collected from 328 nonmanagerial employees working in the refinery, petroleum and power distribution companies who have been convicted for committing environmental irresponsibility by a court of law. Multigroup analysis (MGA) was used to estimate the hypothesized relationships.

Results revealed that CEI affects WDBs positively. Moreover, the MGA results demonstrated that the deviant behavior of Generation Z in response to environmental irresponsibility is higher than of the Millennials.

Theoretically, the findings implicate that harming the environment will cost organizational performance through deviant behaviors.

This study provides a new lens for the executive management that eliminating social irresponsibility is more important than incurring sustainability initiatives, especially from the new generation’s perspective.

The originality of this study is that it confirmed the impact of CEI on employees’ deviant behaviors; and extended the scope of expectancy violation theory to the field of human resources.