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The purpose of this study is to investigate resource-constrained multi-project scheduling problems (RCMPSP) involving uncertainty in the form of time-dependent renewable resource reliability. A key focus is to minimize the makespan (completion time) of projects when resources can become unavailable or fail over time at non-constant rates. Accounting for realistic resource reliability seeks to provide scheduling solutions that better reflect potential delays in practical multi-project environments.

A new discrete-time binary integer programming formulation of RCMPSP is expanded to include time-dependent resource reliability and simultaneously evaluate the time-dependent failure rate and constant repair rate of a resource. A new hybrid immune genetic algorithm with local search (HIGALS) is developed to solve this NP-hard problem. HIGALS incorporates a new coding mechanism, initialization method and local search operator.

A case study tests the proposed HIGALS approach. The validity of the mathematical model is confirmed by solving small-sized problems with GAMS software. The proposed HIGALS algorithm is validated by solving small-sized problems and comparing its solutions with GAMS. The superiority of HIGALS is demonstrated by comparing its solutions with six basic algorithms on medium- and large-sized problems. Results show that HIGALS outperforms existing algorithms, achieving an average reduction in makespan of over 11.79%, while maintaining the advantages of genetic, immune and local search algorithms and avoiding their disadvantages.

Considering time-dependent resource reliability can help project managers plan for disruptions and delays in resource-critical projects. HIGALS provides decision support for robust multi-project scheduling.

This study contributes to the field by investigating RCMPSP with time-dependent renewable resource reliability, which reflects real-world uncertainty more accurately. HIGALS presents a novel approach to balance intensification and diversification for this challenging problem.

Most projects are facing delays, and accelerating the pace of project progress is a necessity. Project managers are responsible for completing the project on time with minimum cost and with maximum quality. This study provides a trade-off between time, cost, and quality objectives to optimize project scheduling.

The current paper presents a new resource-constrained multi-mode time–cost–quality trade-off project scheduling model with lags under finish-to-start relations. To be more realistic, crashing and overlapping techniques are utilized. To handle uncertainty, which is a source of project complexity, interval-valued fuzzy sets are adopted on several parameters. In addition, a new hybrid solution approach is developed to cope with interval-valued fuzzy mathematical model that is based on different alpha-levels and compensatory methods. To find the compatible solution among conflicting objectives, an arithmetical average method is provided as a compensatory approach.

The interval-valued fuzzy sets approach proposed in this paper is denoted to be scalable, efficient, generalizable and practical in project environments. The results demonstrated that the crashing and overlapping techniques improve time–cost–quality trade-off project scheduling model. Also, interval-valued fuzzy sets can properly manage expressions of the uncertainty of projects which are realistic and practical. The proposed mathematical model is validated by solving a medium-sized dataset an adopted case study. In addition, with a sensitivity analysis approach, the solutions are compared and the model performance is confirmed.

This paper introduces a new continuous-based, resource-constrained, and multi-mode model with crashing and overlapping techniques simultaneously. In addition, a new hybrid compensatory solution approach is extended based on different alpha-levels to handle interval-valued fuzzy multi-objective mathematical model of project scheduling with influential uncertain parameters.

This study aims to identify and accurately assess the risk factors of competitors’ cooperation in the NPD project.

New product development (NPD) is essential to the survival of companies and surpassing other competitors. A key prerequisite for the success of an NPD project is the timing of new product delivery to the market. The main challenge faced by many project managers is the delay in execution and completion phases due to the complex nature and uncertainty of these projects. Rival companies' cooperation reduces the time spent on an NPD project which is an excellent way to reduce the risk of losing the market, but it increases other risk factors.

Based on the results, the security and confidentiality of innovation, the competitors attracting human resources and the company’s brand credibility factors were ranked higher than other factors and should be predicted and managed before cooperating with competitors.

This paper proposed a new model to assess risk factors in cooperation with rival companies in NPD projects. This model takes into account new parameters, for example, negative and positive risks, negative and positive passable risks and risk-based multi-objective optimization by ratio analysis plus full multiplicative form methodology for the rival companies cooperation in NPD projects. To evaluate the efficiency of the proposed model, a real case of the R&D unit of Iran Khodro Company was studied.

A multi-objective mixed-integer linear program (MILP) model is developed to address this problem. The primary objective is to minimize the total restructuring cost, while the secondary objective aims to enhance the customer service level. To tackle the NP-hard nature of the problem, the non-dominated sorted genetic algorithm (NSGA-II) and a hybrid NSGA-II with the ɛ-constraint method are employed. The hybrid method combines the strengths of the ɛ-constraint method with NSGA-II. Various performance metrics, including the number of Pareto solutions (NPS), normalized set coverage and spacing metrics, are utilized to compare the characteristics of the non-dominated fronts obtained by NSGA-II and the hybrid methods.

The Restructuring Facility Location Problem involves the closure, resizing or opening of a group of facilities and the assignment of customers to these selected facilities. The objective is to provide the required service to customers while minimizing the overall restructuring costs. This paper introduces a novel multi-objective model for hierarchical facilities called the Multi-Objective Restructuring Hierarchical Facility Location Problem (MO-RHFLP). The model specifically includes primary- and secondary-level facilities, with the primary facility offering broad coverage. In MO-RHFLP, customers within the coverage range of the primary facility can receive service from there.

The results demonstrate that the NSGA-II-based method performs well in terms of normalized set coverage and spacing metrics. However, the hybrid method outperforms NSGA-II in these aspects. Additionally, the hybrid method achieves a mutation in the NPS metric.

The present study, from three perspectives, has continued the way of the previous studies in restructuring channels. First, the multi-objective problem of restructuring the bi-level network executed in this study contains both levels of the network opening, closing and resizing. Taking a different perspective, the MO-RHFLP problem is introduced through the formulation of a multi-objective MILP model. This model serves as a framework for addressing the MO-RHFLP. By developing the hybrid ɛ-constraint method with NSGA-II, we solve the proposed problem.

In this paper, the uncertainties important components and the structure status are obtained by using the condition monitoring, expert groups and multiple membership functions by creating a fuzzy system in MATLAB software.

In the form of fuzzy type, the average structural safety must be followed to replace the damages or to absolutely control the decision-making. Uncertainty in the functionality of hydraulic automated guided vehicles (AGVs), without knowing the reliability of pieces, can cause failure in the manufacturing process. It can be controlled by the condition monitoring pieces done by measurement errors and ambiguous boundaries.

As a result, this monitoring could increase productivity with higher quality in delivery in flexible manufacturing systems with an increase of 70% reliability mutilation for the hydraulic AGV parts.

Hydraulic AGVs play a vital role in flexible manufacturing in recent years. Lately, several strategies for maintenance and repairing of hydraulic AGVs exist in the industry but are still confronted with many uncertainties. The hydraulic AGV is faced with uncertainty after 10 years of working in terms of reliability. Reconstruction of the old parts with the new parts may not have the quality and durability.

The purpose of this paper is to identify factors affecting word-of-mouth (WOM) towards Islamic Banking (IB) in Jordan through understanding the roles of service quality and perceived value.

A self-administered survey was hand-delivered to the targeted sample of Islamic banks customers in Jordan. The authors delivered 400 questionnaires to customers from which 352 were deemed valid for the analysis. Exploratory and confirmatory factor analyses were performed to assess the research constructs validity and composite reliability. Structural path analysis was also used to test the research model and hypothesised relationships between the variables.

Service quality has a positive and significant effect on perceived value and WOM towards IB. Convenience has a positive and significant effect on perceived value. Finally, perceived value has a positive and significant effect on WOM towards IB. Service quality exerted the strongest effect on perceived value and WOM. Also, 38 per cent of variation in perceived value was caused by religious motives, service quality and convenience path, whereas 34 per cent of variation in WOM towards IB was caused by perceived value, service quality and convenience path.

Future research needs to investigate other factors that may affect customers’ WOM concerning IB such as perceived bank image, trust and subjective norms. Future research should investigate other dimensions of perceived value such as social, psychological, emotional, sacrifice value and product values and how they affect WOM. From an international marketing standpoint, comparative studies between Jordanian and non-Jordanian Islamic customers are potential areas of future research for international marketing strategies and cross-cultural consumer behaviour analysis.

The paper identifies the determinants of WOM towards IB. Managers should focus on executing service quality strategies customised towards IB. Convenience is a major driver of perceived value and, then, WOM towards IB. Managers need to focus on key marketing messages that enhance religious motives in customers’ minds and hearts; however, attracting new customers and retaining the current ones depend on the perceived benefits in the areas of service quality, convenience and several value aspects.

This study is the first of its kind to test a model of WOM determinants in IB in Jordan. The study is thought to have made a reasonable contribution to consumer behaviour literature and, specifically, for decision-making process through developing and testing a model of WOM determinants towards IB. The study offers CEOs and marketing managers of Islamic banks new insights into the determinants of WOM and how they contribute to consumers’ decision-making process and attitudes to achieve the intended behavioural outcomes towards IB, which were not available at their hands before. These empirical findings are crucial inputs for marketing strategy formulation and implementation.

This paper aims to investigate the corrosion inhibition ability of 4–(4-nitrophenyl) thiazol-2-amine (NPT) on the copper in 1 M HCl.

The corrosion inhibitory ability of NPT on the copper in 1 M HCl was studied by electrochemical impedance spectroscopy, scanning electron microscopy and atomic force microscopy. Theoretical calculations (molecular dynamics simulation, density functional theory and the nucleus independent chemical shift [NICS] as aromaticity indicator of the molecule) were also performed.

The corrosion inhibition efficacy of this compound was about 80%. Nyquist plots display a small arc contributed to the film or oxide layer resistance and a large loop associated with charge transfer resistance. The inhibitor adsorption was under Langmuir’s adsorption model. ΔG⁰_ads values point to the presence of physical and chemical adsorption. Results of quantum chemical calculations showed that NPT has better interaction with copper than NPTH⁺. NICS of NPT in benzene or thiazole rings was less negative compared to NICS of NPTH⁺. Thus NPT shows less aromaticity compared with NPTH⁺, showing NPT can have better interaction with copper than NPTH⁺. NPT had more negative E_int value and more interactions with the Cu relative to NPTH⁺, this result was in agreement with the results of quantum chemical calculations.

NPT is an efficient corrosion inhibitor for copper in HCl. Theoretical calculations showed that NPT can have better interaction with copper than NPTH⁺. The results of the theoretical studies were in good agreement with the experimental studies.

This paper aims to peruse the influence of second law analysis for electrically conducting fluid of a Casson nanofluid over a wedge. For activation energy, a modified Arrhenius function is used.

The highly non-linear governing equations are developed using similarity transformations and then computed numerically via Keller–Box method.

The influences of emerging parameters on velocity, temperature distribution and concentration of nanoparticle are explained and presented via graphs and tables. Also, the behavior of fluid flow is investigated through the coefficient of skin friction, Nusselt and Sherwood numbers. Results reveal that the velocity profile enhances due to increasing Casson parameter and magnetic parameter, whereas the temperature distribution and concentration of nanoparticle decrease with larger vales of Casson parameter. It is inspected that the concentration boundary layer increases due to activation energy and decreases due to reaction rate and temperature differences.

The authors believe that all the numerical results are original and significant which are used in biomedicine, industrial, electronics and transportation. The results have not been considered elsewhere.

In the face of major disasters, the Chinese people's willingness to donate has increased and the result is that the donation paths have increased. However, there are certain differences in the choice of donation paths for different types of individuals. It is crucial to pay more attention to the attitude and donation path selection of donors and propose strategies to promote individual donation behavior. The purpose of this study is to propose a conceptualized moderated mediation model for testing the linkage between individual attitude and donation path selection through the mediating effect of donors' behavioral intention and the moderating effect of behavioral difficulty perception or social pressure between donors' attitude and their donation path selection.

Based on a questionnaire survey of 628 community workers during COVID-19 in China. Self-reported measures were used to obtain data on IA, BI, SP, BDP and DPS. Survey data were used to test the proposed model using hierarchical regression analysis. Mediation analyses with bootstrap via PROCESS were used to ascertain the proposed relationship.

The results showed that individual attitude are positively related to donation path selection. Moreover, this study finds that behavioral intention serves as a mediator in the relationships between individual attitude and donation path selection. The social pressure and behavioral difficulty perception negatively moderate the relationship between individual attitude and behavioral intention.

There are still some shortcomings in this study: First, although the data collected at multiple points in this study are all individual data. Future research can add evaluations of relatives, friends or colleagues to individual scheduling of survey subjects to reduce homology errors. Second, although this study has verified the mediating role of the opposite sex, some of the mediating results show that there may be other variables that play a role in the relationship between individual attitudes and donation path selection. In the research on path selection, the integrated theoretical perspective has rich connotations but has not attracted enough attention from the academic community. This research is only based on this single theoretical perspective to construct, verify and explain the model, and there should be other integrated theories. The fit point can be used to analyze the influence mechanism of individual attitudes on the choice of donation path.

First of all, we must deepen our understanding of the connotation and role of individuals' attitudes. In the event of a major epidemic, the following two types of measures will be taken to improve individuals' attitudes toward specific donation paths: First, the sponsors of each donation should do their best to donors and provide more information about donations, because the more information resources they have, the stronger the experience of the corresponding donation path, and the more they will choose the path. The sponsor of the second donation must show concern for major epidemics that are prone to occur and a desire to help people affected by disasters, so as to enhance the emotional identity of the donor, thereby increasing the probability of the donor choosing a specific donation path. Secondly, donation sponsors should be wary of the negative influence of social pressure on the donation path selection of individual donors. Donation sponsors can train individuals who are willing to donate, guide them in social relations, online public opinion and other pressure methods and improve the possibility of individuals choosing specific donation routes.

Deepen the understanding of the content and effectiveness of the behavioral difficulty perception that has a profound impact on the donor. The greater the tendency to make a path choice is often affected by the individual's perception of the difficulty of behavior. The perception of difficulty of a certain donation path will cause the individual to retreat and inhibit the possibility of the individual choosing the path. Therefore, donation sponsors should take all measures to make their own donation channels simpler and more efficient, thereby reducing the individual's perception of the difficulty of donation behavior.

Drawing on TPB theory, a theoretical framework is constructed that specifies the process through which individual attitude affects donation path selection to expand collective understandings of individual attitude in the donation context. Furthermore, the boundary conditions of the underlying process are investigated, which further enhances the contribution of this paper to the extant literature on individual attitude.

The purpose of this paper is to study very fast transient overvoltages (VFTOs) in the secondary winding of air‐cored Tesla transformers and also study the resulting electric field stresses.

An exhaustive model based on Multi‐conductor Transmission Lines (MTLs) theory has been used. The governing telegraphist's equations have been solved by Finite Difference Time Domain (FDTD) method.

The results demonstrated that there are some overvoltages at the end and middle turns that should be considered in insulation design. The magnitudes of these overvoltages are several times more than the steady state value of the corresponding turn which cause very high electric field stresses.

The paper describes results obtained from an original and innovative implementation of FDTD method in transmission line modelling and is applied properly to air‐cored pulse transformers.