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In response to the complex external structure of high-precision aviation plugs, which makes it difficult to search outside the hole and adjust inside the hole during automated assembly. This paper aims to propose an assembly framework that combines multi-agent search and variable parameter compliant control to solve this problem.

First, a multi-agent search strategy (MAS) based on Gaussian Mixture Model and Deep Q-Network was proposed to optimize displacement direction and actions, thereby improving search speed and success rate. Then, a variable parameter admittance control method (RL-VPA) based on dual delay depth deterministic policy gradient (TD3) was proposed, which dynamically optimized the internal parameters of the admittance controller and adopted state space discretization to improve convergence speed and assembly efficiency.

Compared to spiral search and single-agent search, the average search success rate has improved by approximately 10% and 6.6%. Compared to fixed admittance control and other RL-based methods, the average assembly success rate has increased by approximately 38.6%, 22% and 8.6%. Compared with the training results of the model without state discretization, it was found that state discretization helps the model converge quickly. To verify the generalization ability of the assembly framework, experiments were conducted on three different pin counts of aviation plugs, the assembly success rate reached 86.7%, all of which showed good assembly results. Finally, combining state space discretization to reduce the impact of environmental noise, improve training effectiveness and convergence speed.

MAS has been proposed to optimize displacement direction and action, improving search speed and success rate. RL-VPA is designed to dynamically optimize the internal parameters of the admittance controller, enhancing the robustness and generalization ability of the model. Additionally, state space discretization is combined to improve training effectiveness and convergence speed.

Construction workers’ safety behavior has been proven to be crucial in preventing occupational injuries and improving workplace safety, and organizational safety support provides essential resources to promote such behavior. However, the specific mechanisms of how organizational safety support affects safety behavior have not been thoroughly explored. Therefore, this study explored the relationship between workers’ perceived organizational safety support (perceived supervisor/coworker safety support) and safety behavior (safety task/contextual behavior), while considering the mediating effects of safety motivation, emotional exhaustion, and the moderating effect of psychosocial safety climate.

Based on the quantitative research method, the hypothesis was tested. The data were collected from 500 construction workers using a structured questionnaire. Observed variables were tested using confirmatory factor analysis, and the path coefficient of fitted model was then analyzed including the associated mediating and moderating effects.

The study found that (1) safety support from both supervisors and coworkers directly forecasted both types of safety behavior, (2) safety motivation was primarily predicted by perceived supervisor safety support, and perceived coworker safety support better predicted emotional exhaustion. Safety motivation mediated the relationship between perceived supervisor safety support and safety contextual behavior, and emotional exhaustion mediated the relationship between both types of safety support and both types of safety behavior, (3) psychosocial safety climate moderated the pathway relationships mediated by safety motivation and emotional exhaustion, respectively.

The samples of this study were mostly immersed in eastern culture and the construction industry, and the cultural and industry diversity of the samples deserves further consideration to enhance the universality of the results. The cross-sectional approach may have some impact on the accuracy of the results. In addition, other potential mediating variables deserve to be explored in future studies.

This study provides a new basis for extending current theoretical frameworks of organizational safety support and safety behavior by using a moderated mediation model. Some practical insights on construction safety management have also been proposed based on the research findings. It is recommended that practitioners should further raise awareness of the critical role of supervisor-worker and worker-coworker relationships, as high levels of safety support from the supervisor/worker respectively effectively encourage safety motivation, alleviate emotional exhaustion, and thus improve workers’ safety performance. Meanwhile, the psychosocial health conditions of workers should also receive further attention.

The purpose of this study is to examine whether service innovation capability can affect firm performance in the architecture, engineering and construction (AEC) context, and, if so, how.

This study developed a theoretical framework illustrating the performance impacts of service innovation capability through the business model in the AEC sector. An empirical study was conducted to test the hypotheses using 374 valid questionnaires using structure equation model (SEM).

The results verify that service innovation capability positively influences firm performance mediated by the business model. As to the direct effect, service innovation capability is positively associated with firm performance.

This study highlights how service innovation capability affects performance and reveals the underlying mechanism.

Medicine distribution logistics pattern in pharmaceutical supply chains is a hot topic, which aims to predict applicable and efficient medicine distribution patterns so that the medicine can be distributed effectively. This research aims to propose a new method, named density-distance method, that works based on Kth proximity using patient features (including age, gender, education, inherent diseases, systemic diseases and disorders); geographical features (city, state, population, density, land area) and supply chain features (destination and transportation system).

The proposed method of this research consists of two main phases where in the first phase, quantitative data analytics will be carried out to find out the significant factors and their impacts on medicine distribution. Then, in the next phase, a new Kth-proximity density-distance-based method is proposed to determine the best locations for the wholesalers while designing a supply chain.

The findings show that the proposed method can effectively design a supply chain network using realistic features. In addition, it is found that while the distance-density aggregate index is applied, the wholesalers' locations will be different compared to classic supply chain designs. The results show that age, public hygiene level and density are the most influential during designing new supply chains.

The outcomes of this research can be used in the medicine supply chains to predict appropriate medicine distribution logistics patterns.

In this research, the machine learning method based on the nearest neighbor has been used for the first time in the design of the supply chain network.

Gears are prone to instantaneous failure when operating under extreme conditions, affecting the machinery’s service life. With numerous types of gear meshing and complex operating conditions, this study focuses on the gear–rack mechanism. This study aims to analyze the effects and optimization of biomimetic texture parameters on the line contact tribological behavior of gear–rack mechanisms under starvation lubrication conditions.

Inspired by the microstructure of shark skin surface, a diamond-shaped biomimetic texture was designed to improve the tribological performance of gear–rack mechanism under starved lubrication conditions. The line contact meshing process of gear–rack mechanisms under lubrication-deficient conditions was simulated by using a block-on-ring test. Using the response surface method, this paper analyzed the effects of bionic texture parameters (width, depth and spacing) on the tribological performance (friction coefficient and wear amount) of tested samples under line contact and starved lubrication conditions.

The experimental results show an optimal proportional relationship between the texture parameters, which made the tribological performance of the tested samples the best. The texture parameters were optimized by using the main objective function method, and the preferred combination of parameters was a width of 69 µm, depth of 24 µm and spacing of 1,162 µm.

The research results have practical guiding significance for designing line contact motion pairs surface texture and provide a theoretical basis for optimizing line contact motion pairs tribological performance under extreme working conditions.

This case study investigates the accessibility and inclusivity of the built environment for students with disabilities at a Malaysian public university.

Utilizing a qualitative approach, the research captures the lived experiences of four undergraduates with physical and visual disabilities through semi-structured interviews guided by the Americans with Disabilities Act checklist.

Findings reveal mixed levels of accessibility across campus, highlighting well-designed areas with accessible pathways and ramps, contrasted with others lacking adequate features and posing significant risks, especially for visually impaired students. The study identifies key design shortcomings, including insufficient safety features in staircases and inconsistent availability of modern technological aids and human assistance. Despite some commendable initiatives, the research underscores the need for comprehensive accessibility audits, consistent application of universal design principles and improved support services. Limitations of the study include its small sample size and focus on a single institution.

By addressing these challenges, universities can foster a more inclusive and supportive environment for students with disabilities, promoting equality within higher education.

Following the tradition of scholarship showing that elites institutionalize their tastes via cultural philanthropy, this chapter investigates patronage of Asian art at the Metropolitan Museum of Art. Drawing on content analysis of museum press releases and other documents, I conceptually elaborate and empirically illustrate different patterns of Asian art patronage among Asian and white patrons as well as among Asian patrons from different ethnic groups. Engaging theory asserting that elites legitimate art tied to their ethnoracial heritage through supporting it at cultural organizations, I elaborate how Asian elites are especially committed to supporting Asian art at the museum. In addition, I illustrate how, compared with each other, Asian elites particularly champion art from their respective ethnic groups – for example, Chinese elites support Chinese art at higher levels than Asian elites who are not Chinese, and Indian elites support Indian art at higher levels than Asian elites who are not Indian. This chapter advances theory about elites and cultural legitimation, elites and organizational contributions, and progressiveness within the elite.

This study aims to report the development and experimental evaluation of two kinds of PANI@semiconductor based photocathodic anti-corrosion coating, for application on stainless steel substrates.

PANI was in situ chemical polymerized on TiO₂ and BiVO₄ particles, and FT-IR and SEM/EDS were used to understand the characteristics and elemental distribution of the composite particles. Composite coatings, which consisted of epoxy, PANI@TiO₂ or PANI@BiVO₄ and graphene, were prepared on the 304L stainless steel. Photoelectrochemical response measurement, electrochemical tests and immersion tests were used to assess the anti-corrosion performance of the prepared coatings in 45°C 3.5 wt.% NaCl solution. And the corrosion protection mechanism was further explained by combining with surface observation.

The photoelectrochemical response tests revealed the good photocathodic effect of the coatings, and the reversible oxidation-reduction properties of PANI (pseudocapacitive effect) leading to the repeated usage of the coatings. Consequently, the anti-corrosion mechanism of the composite coating is attributed to the physical barrier effect of the coating, the anodic protection effect of PANI and the photocathodic and energy store effect.

These kind coatings could prevent corrosion from day to night for stainless steel, which has great engineering application prospects on stainless steel corrosion protection.

This study aims to integrate perspectives of transaction costs and capabilities to investigate how the configurational fit between outsourcing strategies, asset specificity of projects and the capabilities of general contractors could achieve high outsourcing performance.

Employing fuzzy-set qualitative comparative analysis, this study analyzes 31 outsourcing cases in construction projects to examine outsourcing performance under different combinations of transaction costs and capabilities.

The findings highlight six different but functionally equivalent configurations to high outsourcing performance, which vary according to attributes of projects and capabilities of contractors. Further, this study develops four context-dependent paths that link outsourcing strategies to high outsourcing performance: leading practitioner, collaborative manager, partnership dependent, and struggler.

How do contractors in construction projects navigate outsourcing practices to high performance? This study provides a configurational perspective to make outsourcing strategy decisions. Based on the firm’s capabilities and project asset specificity, contractors are encouraged to select from six different but functionally equivalent combinations and thereby four outsourcing strategies, namely leading practitioner, collaborative manager, partnership dependent, and struggler, to achieve high outsourcing performance.

This study contributes to the body of knowledge by offering a holistic perspective that integrates production and transaction costs to analyze contractors’ outsourcing strategies, contributing to the integration of the transaction cost perspective and capability perspective.

Investigation of the anomalies associated with crashes and jackpots in the Chinese stock market.

We propose a logit model to predict the events of crashes and jackpots in the Chinese stock market. The model introduces a new variable of the price-to-sales ratio and takes into account the market states, Up and Down.

The anomalies associated with crashes and jackpots are not related to variations in economic conditions, but are associated with limits to arbitrage. High-liquidity stocks have strong mispricing effects. The institutions’ speculative trading will push liquid stock prices further away from their fundamentals but avoid buying illiquid stocks with a higher probability of price crashes and jackpots.

We propose a logit model to predict the extreme events of both crash and jackpot in the Chinese stock market. Our model effectively disentangles from CRASHP and JACKP. Compared with the traditional model, it substantially enhances in-sample and out-sample predictions. Based on the predictions of the extreme events, we find two strong and robust pricing effects associated with ex ante CRASHP and JACKP in the Chinese stock market.