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Over the past decades, there has been significant research effort dedicated to the development of autonomous vehicles. The decision-making system, which is responsible for driving safety, is one of the most important technologies for autonomous vehicles. The purpose of this study is the use of an intensive learning method combined with car-following data by a driving simulator to obtain an explanatory learning following algorithm and establish an anthropomorphic car-following model.

This paper proposed car-following method based on reinforcement learning for autonomous vehicles decision-making. An approximator is used to approximate the value function by determining state space, action space and state transition relationship. A gradient descent method is used to solve the parameter.

The effect of car-following on certain driving styles is initially achieved through the simulation of step conditions. The effect of car-following initially proves that the reinforcement learning system is more adaptive to car following and that it has certain explanatory and stability based on the explicit calculation of R.

The simulation results show that the car-following method based on reinforcement learning for autonomous vehicle decision-making realizes reliable car-following decision-making and has the advantages of simple sample, small amount of data, simple algorithm and good robustness.

This paper aims to design an automatic inspection system for the characters on tire molds, which involves a vision-based inspection method for the characters on tire molds.

An automatic inspection equipment is designed according to the features of the tire mold. To implement the inspection task, the corresponding image processing methods are designed, including image preprocessing, image mosaic, image locating and character inspection. Image preprocessing mainly contains fitting the contours of the acquired tire mold images and those of the computer aided design (CAD) as the arcs of two circles and polar transformation of the acquired images and the CAD. Then, the authors propose a novel framework to locate the acquired images into the corresponding mosaicked tire mold image. Finally, a character inspection scheme is proposed by combining an support-vector-machine-based character recognition method and a string matching approach. At the stages of image locating and character inspection, image mosaic is simultaneously used to label the defects in the mosaicked tire mold image, which is based on histograms-of-gradients features.

The experimental results indicate that the designed automatic inspection system can inspect the characters on the tire mold with a high accuracy at a reasonable time consumption.

The designed automatic inspection system can detect the carving faults for the characters on the tire molds, which are the cases that the characters are wrongly added, deleted or modified on the tire mold.

To the best of the authors’ knowledge, this is the first automatic vision-based inspection system for the characters on tire molds. An inspection equipment is designed and many novel image processing methods are proposed to implement the inspection task. The designed system can be widely applied in the industry.

This study aims to focus on the heat treatment influence on the corrosion resistance, adhesion of Streptococcus mutans and mechanical properties of CoCrMo alloys manufactured by the selective laser melting (SLM).

CoCrMo alloys were manufactured using the Dimetal-100 machine. X-ray diffraction (XRD), metallographic analysis, scanning electron microscopy (SEM), electrochemical corrosion, Vickers microhardness and tensile tests were used to characterize SLM-produced CoCrMo alloys and compare them with the ones manufactured by casting and with the ASTM F75 standard.

The electrochemical results showed that SLM900 samples had the best corrosion resistance in artificial saliva. The adhesion results showed least propagation and overall quantity of Streptococcus mutans on the SLM900 sample. The microhardness, tensile and yield strength of As-SLM, SLM900 and SLM1200D samples were measured according to the ASTM F75 standard. The elongation of SLM900 was less than 8 per cent, which does not meet the standard specifications. Analysis of the fracture morphology showed that the fracture mechanisms of As-SLM and SLM1200D belong to the quasi-cleavage fracture type, and the mechanical fracture mechanism of SLM900 can be characterized as brittle fracture.

This paper presents the adhesion properties of Streptococcus mutans on the surface of CoCrMo alloys manufactured by SLM and proposes how to regulate the effect of the heat treatment on the corrosion resistance and mechanical properties of CoCrMo alloys manufactured by SLM.

This paper aims to summarize design rules based on the process characteristics of selective laser melting (SLM) and structural optimization and apply the design rules in the lightweight design of an aluminum alloy antenna bracket. The design goal is to reduce 30 per cent of the weight while maintaining the stress levels in the original part.

To reduce weight as much as possible, the titanium alloy with higher specific strength was selected during the process of optimization. The material distribution of the bracket was improved by the topology optimization design. The redesign for SLM was used to obtain an optimization model, which was more suitable for SLM. The component performance was improved by shape optimization. The modal analysis data of the structural optimization model were compared with those of the stochastic lightweight model to verify the structural optimization model. The scanning data were compared with those of the original model to verify whether the model was suitable for SLM.

Structural optimization design for antenna bracket realized the mass decrease of 30.43 per cent and the fundamental frequency increase of 50.18 per cent. The modal analysis data of the stochastic lightweight model and the structural optimization model indicated that the optimization performance of structural optimization method was better than that of the stochastic lightweight method. The comparison results between the scanning data of the forming part and the original data confirmed that the structural optimization design for SLM lightweight component could achieve the desired forming accuracy.

This paper summarizes geometric constraints in SLM and derives design rules of structural optimization based on the process characteristics of SLM. SLM design rules make structural optimization design more reasonable. The combination of structural optimization design and SLM can improve the performance of lightweight antenna bracket significantly.

This paper aims to investigate the Chinese employment relationship under the framework of psychological contracts. The authors explored the effects of firm ownership (in terms of state-owned and private enterprises) and employment type (in terms of permanent and temporary employees) on employee perceptions of psychological contract. In addition, the associations between fulfilled psychological contract and various dimensions of employee attitudes were examined.

The authors adopted a questionnaire as the primary instrument to investigate the impact of firm ownership and employment type on psychological contract perceptions and outcomes. The analysis was based on a Chinese sample of a size of 363 employees.

The results indicate that state-owned employees overall reported fewer promises (employer under-obligation promised psychological contract), while private employees tended to have more promises (mutual high obligation, employer over-obligation and quasi-spot obligation promise-based psychological contract). Permanent employees reported high fulfillment (employer over-obligation, mutual high obligation and employer under-obligation fulfilled psychological contract). In contrast, temporary employees presented many promises (mutual high obligation promised psychological contract) and low fulfillment (quasi-spot fulfilled psychological contract). In general, firm ownership had weak effects on permanent and temporary employees’ perceptions of promise-based psychological contract, but no significant influence on fulfillment-based psychological contract. Moreover, psychological contract fulfillment was positively related to employees’ fairness perception and job satisfaction, while negatively related to the intention to quit. The authors failed to find comprehensive statistical support for the moderating effects of firm ownership or employment type.

The study contributes to the literature through a number of ways. First, instead of psychological contract breach, the authors use psychological contract fulfillment as a direct measure to examine the relationship between psychological contract and employees’ attitudes. Second, they investigate the effects of firm ownership on employment relationship under the psychological contract framework, enriching the institutional lens of the issue. Third, while majority of psychological contract studies concerning employment type concentrate on either permanent or temporary employees, the authors take both types into account. Fourth, they integrate perspectives of firm ownership and employment type. Finally, the authors perform the study in the Chinese context, which offers extra evidence to the body of psychological contract literature.

This paper aims to explore the determinants of maternal and infant health knowledge (M&IHK) adoption and sharing in the short video from an empathy theory perspective. We explore how to transfer users from free health knowledge to health-related product purchase intention, which is vital for platform knowledge management and service.

Focusing on the M&IHK, this study proposes four processes of health knowledge adoption and sharing – knowledge quality persuasion process; source credibility persuasion process; affective empathy emotion process; and cognitive empathy emotion process – to build a framework of M&IHK adoption and sharing. Furthermore, based on adoption and sharing, we explore whether they can promote health-related product purchase intentions. A theoretical model is constructed and tested via Smart PLS in 388 samples.

In a short video context, perceived knowledge quality and perceived source credibility are still two determinants of health knowledge adoption and sharing. On the contrary, perceived affective empathy and perceived cognitive empathy are two new determinants of health knowledge adoption, but not of health knowledge sharing. Adoption of M&IHK is more driven by both rational thinking and emotional thinking than sharing-only driven by emotional thinking. Adoption and sharing both contribute to health-related product purchase intention, but the female’s intention is more related to rational adoption than the male, which is only related to emotional sharing.

This paper is arguably the first study to examine how short videos impact the mechanisms of M&IHK adoption, sharing and health-related products' purchase intention. It’s perhaps the first study to integrate empathy theory into health knowledge management.

The shortage of organ donors is an under-researched global issue that demands immediate attention. This attention should begin at the government level and related organizations. In Malaysia, the shortage of organ donations has been a pressing issue faced by the Ministry of Health Malaysia (MOH) for a considerable length of time. In reaction to this issue, the MOH deployed the Organ Donation Awareness Strategic Campaign Plan by using the platform of social media to disseminate information regarding organ donation to the public. However, the number of registrations is still low among Malaysians. Moreover, the observation from the literature shows that there are limited studies which have been initiated to focus on social media in the context of organ donation campaigns.

The quantitative research design has been used to understand the issue. Three hundred and eighty-four completed questionnaires were collected from the target sample, which comprised university students in Malaysia. For this study, partial least squares structural equation modelling was used for data analysis.

The result shows that information usefulness is vital because it will lead individuals to adopt organ donation information on social media. More specifically, predictors that positively influence youth or university students to accept information as useful are visual information, information sharing, accessibility of information, needs of information and attitude towards information. Subsequently, information usefulness positively influences information adoption. In the meantime, information quality and credibility do not significantly affect information usefulness.

The findings of this study may assist MOH or interested parties in designing a sound marketing strategy in the context of organ donation promotion by providing empirical evidence.

The study provides empirical evidence about information characteristics in the context of organ donation promotion.