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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.

The cable inspection robot is essential in maintaining bridge cables. The purpose of this paper is to summarize the maintenance methods of bridge cables. It summarizes the advantages and disadvantages of the critical structures of the external overall frame, intermediate adhesion device, attachment mechanism and driving method of the cable inspection robot. Finally, it discusses the challenges the cable inspection robot faces and the direction of future research.

This paper summarizes the research progress of the cable inspection robot and details the advantages and disadvantages of critical structures such as the external frame, intermediate adhesion device, attachment mechanism, driving method and safe return device of the robot. Finally, it points out the future direction of cable inspection robots, including lightweight design, hybrid design, multi-robot cooperative work, multi-technology integration and intelligent cable inspection digital twin model.

The cables are the main load-bearing components of a bridge, and their safety is crucial. However, subjected to varying loads and environmental influences over a long period, cables are prone to damage, threatening the bridge’s stability. Cable inspection robots can comprehensively detect and repair cable damage, significantly improving efficiency and safety.

This paper provides a comprehensive review of the current research on cable inspection robots, enabling readers to have a comprehensive and systematic understanding of the critical structures and key technologies of cable inspection robots and providing scientific references for researchers working on cable inspection robots.

This study aims to examine the mediating role of social influence on the relationship between key predictors of E-pharmacy adoption among young consumers based on the unified theory of adoption and use of technology (UTAUT).

This study employs a quantitative correlational research design. Based on cluster sampling, data was collected from 306 university students from three public universities in southwestern Nigeria. Data was analysed using partial least square structural equation modeling.

The primary determinant driving the adoption of e-pharmacy is performance expectancy. Social influence plays a partial mediating role in linking performance expectancy to e-pharmacy adoption. In contrast, it fully mediates the relationship between effort expectancy, facilitating conditions and the adoption of e-pharmacy services.

This study provides theoretical clarity on recent issues within the UTAUT framework. Findings highlight the complexity of how social factors interact with individual beliefs and external conditions in determining technology acceptance.

Research includes information relevant to access the impact of e-pharmacy services on healthcare accessibility, affordability and quality in developing countries.

The findings extend the adoption of technology literature in healthcare and offer a new understanding of adoption dynamics. The results emphasize the importance of performance expectancy in driving e-pharmacy adoption, providing a clear direction for stakeholders to enhance service quality and user experience of e-pharmacy. Additionally, the mediating effect of social influence highlights the significance of peer recommendations, celebrity endorsements and social media campaigns in shaping consumer adoption of e-pharmacies among young people.

In the context of the severe global challenges posed by climate and environmental issues, this paper aims to explore the connection between female Chief Executive Officers (CEOs) and the level of sustainable development in companies. This study aims to investigate the impact of female CEOs on corporate ESG performance and provide a detailed analysis of the underlying mechanisms.

This study uses a sample of listed companies from 2010 to 2021, as reported by Bloomberg. This study uses logit regression models to test hypotheses and conduct robustness tests using the generalized method of moments, propensity score matching and heckman two statge tests.

The research findings indicate that female CEOs can enhance a company’s ESG performance, primarily by elevating the level of green innovation and engaging in more philanthropic activities. When environmental uncertainty is high, the risk-averse attitude of female CEOs may diminish the enhancement of ESG performance. However, granting a higher proportion of equity to female CEOs incentivizes risk-taking, thereby strengthening the improvement of ESG performance. Further analysis reveals that the impact of female CEOs on ESG performance is more significant in non-state-owned enterprises, high-pollution industries, and companies with low financing constraints.

The authors have shown that two key ways in which female CEOs enhance a company’s ESG performance are by increasing the level of green innovation and assuming more social responsibility. Nonetheless, this remains a shortcoming of this work, opening a door for future research to examine and enrich. There may be other possible mechanisms explaining the influence of female CEOs on corporate ESG performance. More research is warranted about the CEO’s additional traits, which were not considered in this study but may have an impact on a company’s ESG performance. Finally, while the analysis has delved into the moderating effects of external factors such as environmental uncertainty and CEO ownership on the influence of female CEOs on corporate ESG performance, there is room for exploring whether other factors also play a moderating role in future studies.

First, the findings of this study highlight the beneficial societal and economic effects of choosing female CEOs. The inclination to take on social responsibility and care for the environment are both higher among female CEOs. Furthermore, the authors have also discovered that female CEOs possess unique advantages in promoting corporate sustainability and enhancing ESG standards. This can contribute to breaking down stereotypes about gender roles in the workplace. Finally, this research shows that organizational heterogeneity and market risks have an impact on female CEOs’ capacity to improve company ESG performance.

A significant innovation of this paper lies in its unique focus on the connection between female CEOs and corporate ESG performance, along with the underlying mechanisms. Against the backdrop of sustainable development, the paper integrates social gender theory, upper echelon theory and agency theory into a comprehensive framework, shedding light on the influence of female CEOs on ESG performance and the associated mechanisms.

This study aims to improve the force sensing performance of the robot joint for the safety and flexibility of physical human–robot interaction.

A force sensing mechanism (FSM) for an S-shaped spring of a robot variable stiffness actuator (VSA) was designed. The yield strength of the spring material, geometric and assembly structure constraints of the VSA are all considered for the actuator deflection limit design. The elastic deformation model is solved in reverse to obtain the local deformation limit profile of the S-spring at different spring angles. The deformation limit mechanism is manufactured by three-dimensional printing and assembled with S-springs. The force sensing function for the VSA is achieved by the input and output shaft encoders and stiffness model. The FSM is verified by torque-deflection experiments with variable stiffness.

The yield strength of the S-spring material is the strictest constraint for elastic deformation. Experimental results show that the external force can be quickly and reliably perceived. As the spring angle increases (stiffness increases), the hysteresis and nonlinear error decrease. Under the constraint of the FSM, the maximum deflection also decreases rapidly.

The designed FSM based on the deformation and stiffness model provides a comprehensive design reference in a VSA with nonlinear elastic mechanisms, which is ignored but important for exploring the VSAs potential.

Drawing on the tenets of institutional theory, the purpose of this study is to examine the impact of Confucianism on technology for social good, while also considering the moderating influence of extrinsic informal institutions (foreign culture) and intrinsic formal institutions (property rights).

This study constructs a comprehensive database comprising 9,759 firm-year observations in China by using a sample of Chinese A-share listed firms from 2016 to 2020. Subsequently, the hypotheses are examined and confirmed, with the validity of the results being upheld even after conducting endogenous and robustness tests.

The findings of this study offer robust and consistent evidence supporting the notion that Confucianism positively affects technology for social good through both incentive effect and normative effect. Moreover, this positive influence is particularly prominent in organizations with limited exposure to foreign culture and in nonstate-owned enterprises.

The findings contribute to the literature by fostering a deep understanding of technology for social good and Confucianism research, and further provide a nuanced picture of the role of foreign culture and property rights in the process of technology for social good in China.

The impact of banking deregulation on firms and economic growth is heavily researched, but not the effects on banks’ risk-taking. This study aims to investigate the impact of China’s 2009 banking deregulation on bank risk-taking, particularly from a balance sheet capacity perspective.

Using a difference-in-differences approach, this study examines how deregulation affects bank risk-taking. A three-stage regression strategy is employed to conduct mechanism analysis.

The results reveal that deregulated banks exhibit higher levels of risk-taking. Mechanism analysis confirms the bank balance sheet capacity channel: deregulation helps strengthen the net interest margin of deregulated banks, which enhances their balance sheet capacity and subsequently increases their risk appetite. In addition, deregulation improves firms’ access to long-term credit in regions with limited credit availability, especially for smaller firms, thereby expanding the financial sector’s service outreach.

While banking deregulation enhances credit availability for firms and supports the real economy, it also raises banks’ risk-taking, posing challenges to financial stability. Our study highlights the trade-off between supporting the real economy and maintaining financial stability under banking deregulation.

This study fills a gap in research on the effects of banking deregulation on bank risk-taking, highlighting the critical role of balance sheet capacity in this process.

This study aims to examine the extent to which information asymmetry affects investment efficiency and whether the presence of blockholders moderate this relationship.

We employ the data of firms listed on the Malaysian stock exchange for the period 2010–2018, to compose our sample. Our final sample includes the 100 largest non-financial firms based on market capitalization. Collectively, these 100 companies contribute 84.2% to the total market capitalization (MYR 1,730bn) which is representative of the whole market. The ordinary least squares regressions were used as the main estimation technique. The system generalized method of moments, two-stage least squares and propensity score matching were also used, to address potential endogeneity concerns.

We document a positively significant association of information asymmetry with investment inefficiency. These results imply that information asymmetry reduces investment efficiency and enhances sub-optimal investments. We also document that blockholders negatively moderate the relationship of information asymmetry with investment inefficiency. Further analyses show that investment inefficiency is higher in low-growth firms than in high-growth firms because of higher information asymmetry.

We focus on Malaysia, which is a predominantly common-law Anglo-Saxon country. Graff (2008) documented that the investors are treated differently across legal systems and there are differences between the continental European and Anglo-Saxon countries. La Porta et al. (1999) documented that investors tend to have more legal protection in Anglo-Saxon countries. Therefore, our results may not be generalized to countries with different legal systems.

An important implication of our findings is that stakeholders may encourage the presence of blockholders and give them a voice to weaken the positive relationship between information asymmetry and investment inefficiency.

This study contributes to the contingency literature by investigating the moderating effect of an important governance mechanism, i.e. the presence of blockholders on information asymmetry-investment efficiency nexus. Despite being important, this moderating effect has been largely overlooked in the literature. Our study contributes by providing an understanding of how blockholders can influence investment decisions, offering insights for academics, investors and policymakers focused on improving the efficacy of investment decisions and governance structure.

The purpose of this paper is to analyze and compare the mechanical properties of sintered nanosilver with different porosities at both the mesoscopic and macroscopic scales and to conduct a multiscale analysis of the porosity effect on the mechanical properties of sintered nanosilver.

This paper establishes a mesoscopic model for the uniaxial tension of sintered nanosilver and a macroscopic model for chips containing sintered silver layers. Using the finite element method, combined with crystal plasticity theory and unified creep plasticity theory, a multiscale analysis is conducted for the mechanical properties of sintered nanosilver. First, stress distribution characteristics under uniaxial tensile loading for different porosities in sintered nanosilver polycrystal models are analyzed at the mesoscopic scale. Second, at the macroscopic scale, the mechanical performance of sintered nanosilver layers with varying porosities in high-power chip models under cyclic loading is analyzed. Finally, the porosity influence on the damage evolution in sintered nanosilver is summarized, and simulations are conducted to explore the evolution of damage parameters in sintered nanosilver under different porosities.

In the mesoscopic model, the presence of mesoscale voids affects the stress distribution in sintered nanosilver subjected to tensile loading. Sintered nanosilver with lower porosity exhibits higher tensile strength. In the macroscopic model, sintered nanosilver layers with lower porosity correspond to a more uniform stress distribution, whereas higher porosity leads to faster accumulation of plastic strain in the sintered layer. During chip packaging processes, improving processes to reduce the porosity of sintered layers can delay the initiation of damage and the propagation of cracks in sintered nanosilver.

During chip packaging processes, improving processes to reduce the porosity of sintered layers can delay the initiation of damage and the propagation of cracks in sintered nanosilver.

This paper innovatively uses a mesoscopic crystal plasticity constitutive model and a macroscopic unified creep plasticity constitutive model to analyze the mechanical behavior of sintered nanosilver with different porosities. It comprehensively investigates and explains the influence of porosity on the mechanical performance of sintered nanosilver across multiple scales.

The study aims to investigate the impact of state ownership on company market performance, i.e. on share price returns and volatility, during the COVID-19 pandemic.

The study analyzes data from 125 companies listed on the Warsaw Stock Exchange between 2019 and 2020. Cumulative abnormal rates of return and quarterly standard deviation are used to measure investment return and price volatility. Panel ordinary least square regression models assess the influence of state ownership on stock market dynamics.

Our findings indicate that state ownership has a dual impact on share prices: it reduces both share price growth and volatility. The significant reduction in share price volatility provides evidence that state ownership enhances stability in uncertain market conditions, benefiting from governmental support.

Our findings convey to investors that state ownership promotes share price stability but may not lead to substantial increases in market value. To maintain a stable SOE share price, the state as a shareholder should be credible to investors, i.e. act transparently and inform the market about planned activities.

Previous studies concentrate mainly on the impact of state ownership on financial performance during the pandemic, while in a much lesser scope on market performance. We contribute to the literature by providing a more comprehensive understanding of the impact of state ownership on corporate market performance, particularly during the pandemic, through the lens of agency theory and resource-based theory.