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The purpose of this paper is to provide an experimental basis for studying the effects of laser remelting on the surface modification of arc-sprayed Al coating.

A layer of arc-sprayed Al coating on S355 steel was remelted with a CO₂ laser, and the surface-interface morphologies, compositions of chemical elements and phases of Al coating were analyzed with scanning electron microscopy, energy disperse spectroscopy and X-ray diffraction, respectively. The effects of laser remelting on compositions of chemical elements and bonding performance of Al coatings were discussed.

The result shows that there are some pores existing on the Al coating surface after arc spraying, and the combination mode of coating interface is primarily composed of mechanical bonding. The pores on the Al coating reduce after laser remelting, which improves the compact performance, and the mechanical binding mode by arc spraying is changed into metallurgical bonding. The Fe and Al atoms at the coating interface are distributed with gradient, and the stratified enrichment is evident, which improves binding performance of the Al coating. The Al coating exhibits general corrosion before laser remelting and local corrosion after laser remelting, which improves the corrosion resistance of Al coating.

The arc-sprayed Al coating is remelted by CO₂ laser, improving its microstructures and bonding mode with the substrate.

Session-based recommendation aims to predict the user's next preference based on the user's recent activities. Although most existing studies consider the global characteristics of items, they only learn the global characteristics of items based on a single connection relationship, which cannot fully capture the complex transformation relationship between items. We believe that multiple relationships between items in learning sessions can improve the performance of session recommendation tasks and the scalability of recommendation models. At the same time, high-quality global features of the item help to explore the potential common preferences of users.

This work proposes a session-based recommendation method with a multi-relation global context–enhanced network to capture this global transition relationship. Specifically, we construct a multi-relation global item graph based on a group of sessions, use a graded attention mechanism to learn different types of connection relations independently and obtain the global feature of the item according to the multi-relation weight.

We did related experiments on three benchmark datasets. The experimental results show that our proposed model is superior to the existing state-of-the-art methods, which verifies the effectiveness of our model.

First, we construct a multi-relation global item graph to learn the complex transition relations of the global context of the item and effectively mine the potential association of items between different sessions. Second, our model effectively improves the scalability of the model by obtaining high-quality item global features and enables some previously unconsidered items to make it onto the candidate list.

We make use of the Volunteered Geographic Information (VGI) data to extract the total extent of the roads using remote sensing images. VGI data is often provided only as vector data represented by lines and not as full extent. Also, high geolocation accuracy is not guaranteed and it is common to observe misalignment with the target road segments by several pixels on the images. In this work, we use the prior information provided by the VGI and extract the full road extent even if there is significant mis-registration between the VGI and the image. The method consists of image segmentation and traversal of multiple agents along available VGI information. First, we perform image segmentation, and then we traverse through the fragmented road segments using autonomous agents to obtain a complete road map in a semi-automatic way once the seed-points are defined. The road center-line in the VGI guides the process and allows us to discover and extract the full extent of the road network based on the image data. The results demonstrate the validity and good performance of the proposed method for road extraction that reflects the actual road width despite the presence of disturbances such as shadows, cars and trees which shows the efficiency of the fusion of the VGI and satellite images.

This study aims to investigate the initial corrosion behavior in aqueous solution of 20# seamless steel under (CO₂/aqueous solution) gas–liquid two-phase stratified flow conditions.

The initial corrosion behavior was studied through the weight loss methods, scanning electron microscopy with energy-dispersive x-ray spectroscopy and x-ray diffraction.

The corrosion rate of 20# steel obviously increases with the increasing gas pressure at different corrosion time when the CO₂ pressure is less than 0.11 MPa, and the increase of corrosion rate tends to be steady when the pressure exceeds 0.11 MPa. With the increase of CO₂ pressure, the corrosion products changed from flocculent to acicular, granular and scaly. A four-stage model for the growth of the corrosion product layer was proposed, namely, the diffusion reaction stage, the local film formation stage, the complete film formation stage and the densification stage of the product film.

A four-stage model for the growth of the corrosion product layer on the pipe wall surface under this condition was proposed, namely, the diffusion reaction stage, the local film formation stage, the complete film formation stage and the densification stage of the product film. The growing process and densification mechanism of corrosion products layer were discussed.

This study aims to take advantage of the unprecedented anti-corruption campaign launched in China in December 2012 and examine the effect of improved public governance on tunneling.

This study uses a sample of Shanghai and Shenzhen Stock Exchange listed companies from 2010 to 2014 and conduct regression analyses to investigate the effect of improved public governance attributed to the anti-corruption campaign on tunneling.

This study finds that the level of tunneling decreased significantly after the anti-corruption campaign, suggesting that increased public governance effectively curbs tunneling. Cross-sectional results show that this mitigating effect is more pronounced for non-SOE firms, especially non-SOE firms with political connections, firms audited by non-Big 8 auditors, firms with a large divergence between control rights and cash flow rights and firms located in areas with lower marketization.

This study highlights the importance of anti-corruption initiatives in improving public governance and in turn reducing tunneling. This study provides important implications for many other emerging economies to improve public governance.

This study contributes to the literature on the role of public governance in constraining corporate agency problems and advances the understanding of the economic consequences of China's anti-corruption campaign in the context of tunneling.

The specific iron losses of amorphous alloy material are extremely low compared with silicon steel material. The iron losses of motors may reduce by replacing the silicon steel core with an amorphous alloy core. However, one drawback of amorphous alloy material is that the specific iron losses will increase a lot after the motor manufacturing process. This paper aims to study the influences of interlaminar insulator solidifying and annealing on amorphous alloy material. The iron losses of motors made of amorphous alloy and baseline silicon steel sheets are compared and discussed.

This paper opted for an exploratory study using the experimental analysis and loss separation methods. Two amorphous alloy cores are produced and tested. The iron losses of motors made of amorphous alloy and silicon steel sheets are calculated and compared based on the measured specific iron losses. Three wound amorphous alloy core samples are made and measured. The iron losses are separated and compared by considering the manufacturing influences.

This paper provides empirical insights about what change is brought in amorphous alloy material after manufacturing. The results have shown that, for amorphous alloy cores without the annealing process, the loss increase caused by solidifying is mainly the eddy current loss, while it is mainly the hysteresis loss component for annealed amorphous alloy cores.

This paper presents for the first time the measured results of manufactured amorphous alloy cores. This paper fulfils the need to manufacture amorphous alloy motors properly for the producers.

The purpose of this paper is the research of a novel gesture-based dual-robot collaborative interaction interface, which achieves the gesture recognition when both hands overlap. This paper designs a hybrid-sensor gesture recognition platform to detect the both-hand data for dual-robot control.

This paper uses a combination of Leap Motion and PrimeSense in the vertical direction, which detects both-hand data in real time. When there is occlusion between hands, each hand is detected by one of the sensors, and a quaternion-based algorithm is used to realize the conversion of two sensors corresponding to different coordinate systems. When there is no occlusion, the data are fused by a self-adaptive weight fusion algorithm. Then the collision detection algorithm is used to detect the collision between robots to ensure safety. Finally, the data are transmitted to the dual robots.

This interface is implemented on a dual-robot system consisting of two 6-DOF robots. The dual-robot cooperative experiment indicates that the proposed interface is feasible and effective, and it takes less time to operate and has higher interaction efficiency.

A novel gesture-based dual-robot collaborative interface is proposed. It overcomes the problem of gesture occlusion in two-hand interaction with low computational complexity and low equipment cost. The proposed interface can perform a long-term stable tracking of the two-hand gestures even if there is occlusion between the hands. Meanwhile, it reduces the number of hand reset to reduce the operation time. The proposed interface achieves a natural and safe interaction between the human and the dual robot.

The incentive cost of enterprises increases significantly with the rapid growth of the social commerce (SC) market. In this context, enterprises need to develop the optimal strategy to improve incentive effectiveness and reduce cost. Different types of consumers’ responses to incentives bring different values to enterprises. Hence, this paper proposes the social commerce value network (SCVN) to help enterprises study the contributions of different types of consumers to the network.

Based on the graphical evaluation and review technique (GERT), the authors construct the social commerce value GERT (i.e. SCV-GERT) network and design three progressive experiments for estimating the value contributions of “network stage”, “consumer type”, and “resource type” to the SCVN under the same incentives. The authors initialize the SCV-GERT model with consumer data in SC and distinguish the most valuable consumers by adjusting the incentive parameters.

The results show that the SCV-GERT model can well describe the value flow of SCVN. The incentive on forwarding consumers brings the greatest value gain to the SCVN, and social trust contributes the most to forwarding consumers.

Under the guidance of the results, platforms and enterprises in SC can select the optimal type of consumers who bring the maximum network value so as to improve the effectiveness of incentive strategy and reduce marketing costs. A four-level incentive system should be established according to the ranking of the corresponding value gains: forwarding consumers > agent consumers > commenting consumers > potential consumers. Enterprises also need to find ways to improve the social resource investments of consumers participating in SC.

This paper investigates the incentive problem in SC grounded in the SCVN and uses the GERT method to construct the SCV-GERT model, which is the first attempt to introduce GERT into the SC context. This study also makes up for the lack of comparative research on different types of consumers in SC and can provide support for enterprises’ customer relationship management and marketing decisions.

Goal orientation shapes employees’ approach to and interpretation of workplace aspects such as supervisors’ behavior. However, research has not fully examined the effect of goal orientation as an antecedent of abusive supervision. Drawing from victim precipitation theory, this study aims to fill this research gap by investigating how employees’ goal orientation influences their perception of abusive supervision.

Two studies were conducted to test the hypotheses. In Study 1, 181 employees in 45 departments participated in the survey, and multilevel confirmatory factor analysis, two-level path model and polynomial regression were used. In Study 2, 108 working adults recruited from a professional online survey platform participated in a two-wave time-lagged survey. Confirmatory factor analysis, hierarchical linear regression and polynomial regression were used.

This study found that employees’ learning goal orientation was negatively related to their perception of abusive supervision. In contrast, performance-avoidance goal orientation was positively related to their perception of abusive supervision, whereas performance-approach goal orientation was unrelated to this perception. Moreover, employees’ perception of abusive supervision was greater when learning and performance-approach goal orientation alignment occurred at lower rather than higher levels, and when performance-avoidance and performance-approach goal orientation alignment occurred at higher rather than lower levels.

This research identified two novel victim traits as antecedents of abusive supervision – employees’ learning goal orientation and performance-avoidance goal orientation. Furthermore, adopting a multiple goal perspective, the authors examined the combined effects of goal orientation on employees’ perception of abusive supervision.

The cruise industry has witnessed steady growth, with passenger volume increasing from 17.8 million in 2009 to 30 million in 2019. In the context of global competition and an uncertain business environment, competition in business has changed dramatically from battles of “firm versus firm” to “supply chain versus supply chain”. Hence, the purpose of this paper is to understand the cruise industry from a chain perspective, which has not drawn widespread research attention.

This paper brings together the insights, opinions, concepts and frameworks from a literature review of different disciplines (maritime shipping, tourism management, logistics management, operations management and supply chain management) and analysis results from 22 semi-structured interviews to make an early attempt to conceptualise the cruise supply chain (CSC).

The cruise supply chain is elaborated on the process, the role of each entity and its characteristics by comparing with the maritime supply chain and tourism supply chain. Based on the understanding of the CSC, two specific characteristics of the Chinese CSC are examined, which need further investigation.

The CSC is articulated with detailed processes and characteristics based on the literature review and empirical study. The findings of this paper not only advance the knowledge of the supply chain in the cruise industry but also highlight the importance of further research on the CSC.