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This paper aims to focus on the spatial docking task of unmanned vehicles under ground conditions. The docking task of military unmanned vehicle application scenarios has strict requirements. Therefore, how to design a docking robot mechanism to achieve accurate docking between vehicles has become a challenge.

In this paper, first, the docking mechanism system is described, and the inverse kinematics model of the docking robot based on Stewart is established. Second, the genetic algorithm-based optimization method for multiobjective parameters of parallel mechanisms including workspace volume and mechanism flexibility is proposed to solve the problem of multiparameter optimization of parallel mechanism and realize the docking of unmanned vehicle space flexibility. The optimization results verify that the structural parameters meet the design requirements. Besides, the static and dynamic finite element analysis are carried out to verify the structural strength and dynamic performance of the docking robot according to the stiffness, strength, dead load and dynamic performance of the docking robot. Finally, taking the docking robot as the experimental platform, experiments are carried out under different working conditions, and the experimental results verify that the docking robot can achieve accurate docking tasks.

Experiments on the docking robot that the proposed design and optimization method has a good effect on structural strength and control accuracy. The experimental results verify that the docking robot mechanism can achieve accurate docking tasks, which is expected to provide technical guidance and reference for unmanned vehicles docking technology.

This research can provide technical guidance and reference for spatial docking task of unmanned vehicles under the ground conditions. It can also provide ideas for space docking missions, such as space simulator docking.

This study aims to address the issue of random movement and non coordination between docking mechanisms and locking mechanisms, and proposes a comprehensive dynamic docking control architecture that integrates perception, planning, and motion control.

Firstly, the proposed dynamic docking control architecture uses laser sensors and a charge-coupled device camera to perceive the pose of the target. The sensor data are mapped to a high-dimensional potential field space and fused to reduce interference caused by detection noise. Next, a new potential function based on multi-dimensional space is developed for docking path planning, which enables the docking mechanism based on Stewart platform to rapidly converge to the target axis of the locking mechanism, which improves the adaptability and terminal docking accuracy of the docking state. Finally, to achieve precise tracking and flexible docking in the final stage, the system combines a self-impedance controller and an impedance control algorithm based on the planned trajectory.

Extensive simulations and experiments have been conducted to validate the effectiveness of the dynamic docking system and its control architecture. The results indicate that even if the target moves randomly, the system can successfully achieve accurate, stable and flexible dynamic docking.

This research can provide technical guidance and reference for docking task of unmanned vehicles under the ground conditions. It can also provide ideas for space docking missions, such as space simulator docking.

This paper aims to investigate an autonomous obstacle-surmounting method based on a hybrid gait for the problem of crossing low-height obstacles autonomously by a six wheel-legged robot. The autonomy of obstacle-surmounting is reflected in obstacle recognition based on multi-frame point cloud fusion.

In this paper, first, for the problem that the lidar on the robot cannot scan the point cloud of low-height obstacles, the lidar is driven to rotate by a 2D turntable to obtain the point cloud of low-height obstacles under the robot. Tightly-coupled Lidar Inertial Odometry via Smoothing and Mapping algorithm, fast ground segmentation algorithm and Euclidean clustering algorithm are used to recognize the point cloud of low-height obstacles and obtain low-height obstacle in-formation. Then, combined with the structural characteristics of the robot, the obstacle-surmounting action planning is carried out for two types of obstacle scenes. A segmented approach is used for action planning. Gait units are designed to describe each segment of the action. A gait matrix is used to describe the overall action. The paper also analyzes the stability and surmounting capability of the robot’s key pose and determines the robot’s surmounting capability and the value scheme of the surmounting control variables.

The experimental verification is carried out on the robot laboratory platform (BIT-6NAZA). The obstacle recognition method can accurately detect low-height obstacles. The robot can maintain a smooth posture to cross low-height obstacles, which verifies the feasibility of the adaptive obstacle-surmounting method.

The study can provide the theory and engineering foundation for the environmental perception of the unmanned platform. It provides environmental information to support follow-up work, for example, on the planning of obstacles and obstacles.

This study is a reference for manufacturers who are promoting their product-service system (PSS) development. Currently, improvements in both digital customization and sustainability for various smart PSS categories have been considered rarely. This paper addresses this research gap by developing relevant models.

The development trends of customization-oriented PSS are described in a literature review. An in-depth multiple-case study methodology is adopted, and seven manufacturing companies are sampled. The goal is to identify digital customization measures that can be employed on representative smart PSS models and to explore how these models can create sustainable value.

This study provides valuable insights by uncovering a synthesis framework for achieving customization of the product/use/result-oriented smart PSSs, and the relevant representative smart functions are summarized. This identifies how digital customization capabilities can improve sustainability, including direct economic value for customers as well as additional social benefits and environmental improvements during customization.

Currently, the influence of digitalization on customized offerings and the relevant impact on sustainability development have not been fully addressed to date. This study provides comprehensive information with a reference value for digital customization transformation among the three main types of smart PSS.

This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/17488840610639681. When citing the article, please cite: Xiujie Jiang, Huixian Sun, Xiaomin Chen, Zhihua Wang, Li Zhang, Daxing Wang, (2006), “Utilization of a COTS component in temperature measurement system for microgravity fluid experiment on SZ-4 spaceship”, Aircraft Engineering and Aerospace Technology, Vol. 78 Iss: 1, pp. 45 - 49.

The purpose of this paper is to investigate the relationships between supply chain quality management (SCQM) and firm performance (including quality safety performance and sales performance) leveraging social co-regulation as a moderator.

Using survey data collected from 203 food manufacturers in China, a series of hierarchical linear modeling analyses were conducted to test hypotheses on the relationships between SCQM and firm performance.

The findings are threefold. First, all three dimensions of food SCQM practices, i.e., supplier quality management, internal quality management, and customer quality management, have significant positive effects on an enterprise's quality safety performance and sales performance. Second, SCQM practices can also increase sales performance indirectly through quality safety performance as a mediator. Third, while social co-regulation has no significant effect on the relationship between supplier quality management and quality safety performance, it has a significant moderating effect on the relationship between internal quality management and quality safety performance, customer quality management and quality safety performance.

This study not only integrates SCQM with social co-regulation but also explores the regulating effect of social co-regulation through empirical analysis, thereby providing a theoretical base for future research. However, this research is confined to China and so the results are not necessarily generalizable to other countries.

The findings inform managers of the importance in enhancing awareness of food quality and safety as well as in improving their sensitivity to salient quality demands of external stakeholders in order to achieve better SCQM practices. The findings can also inform policymakers of the significance in designing a systematic multi-agent cooperation mechanism for food SCQM as well as to build an effective information sharing mechanism for social co-regulation of food safety.

This study contributes to knowledge by empirically examining the relationships of SCQM practices with firm performance. It also expands the scope of SCQM research by incorporating social co-regulation in the study framework.

Addressing users’ migration is a prerequisite for the sustainable development of the sharing economy. Ethical concerns that may lead to users’ migration are frequent in sharing economy platforms. Therefore, this study explores whether the long-term governance of sharing economy platforms can effectively mitigate users’ migration caused by ethical concerns.

Using a questionnaire survey of 549 participants, this study investigated the mechanism of users’ migration and governance strategies in the platform ecosystem based on trust theory.

The results indicate that users’ ethical concerns regarding the platform ecosystem significantly and positively influence their migration. Furthermore, users’ continued trust played a significant mediating role in the relationship between ethical concerns and users’ migration. The results also showed that future orientation and resilience significantly moderated the impact of users’ ethical concerns on their continued trust, thereby weakening this effect.

The author clarified the relationship between ethical concerns and users’ migration, identified the underlying mechanisms and provided guidance on how to mitigate migration behavior. However, users’ migration is influenced by various factors beyond ethical concerns. In addition to some factors that lead to migration, other factors make users stay on the platform. Future research should integrate multiple factors.

This study reveals the mechanism of action between users’ migration and ethical concerns in the platform ecosystem and sheds light on the output of long-term orientation practices of the platform.

The purpose of this paper is to form good cutting qualities in glass-epoxy material for opening flexible areas of rigid-flex printed circuit boards (PCB) by ultraviolet (UV) laser cutting.

The cut width and cut depth of glass-epoxy materials were both observed to evaluate their cutting qualities. The heat affected zone (HAZ) of the glass-epoxy material was also investigated after UV laser cutting. The relationships between the cut width and the parameters of various factors were analyzed using an orthogonal experimental design.

The cut width of the glass-epoxy material gradually increased with the increment of the laser power and Z-axis height, while cutting speed and laser frequency had less effect on the cut width. Optimal parameters of the UV laser process for cutting glass-epoxy material were obtained and included a laser power of 6W, a cutting speed of 170 mm/s, a laser frequency of 50 kHz and a Z-axis height of 0.6 mm, resulting in an average cut width of 25 μm and small HAZ.

Flexible areas of rigid-flex PCBs are in good agreement with the cutting qualities of the UV laser. The use of a UV laser process could have important potential for cutting glass-epoxy materials used in the PCB industry.

This paper aims to convict the offender of real concurrence offenses of the most severe offense and applying the most severe penalty will result in no distinction between the perpetrator who conducted more than one act and the one who conducted only one act. This approach deviates from the purpose of criminal law. The real concurrence of offenses means several offenses, the perpetrator’s dangerousness and culpability are much higher than the perpetrator who commits just one crime, so combined punishments for several offenses should be applied to the real concurrence of offenses.

If the depositors are acquaintances or relatives and friends, the relationship can be explained by “personality trust.” If the depositors are strangers, but they have complied with their duties of care, the deposit relationship can be explained by “system trust.”

The real concurrence of offenses means several offenses, the perpetrator’s dangerousness and culpability are much higher than the perpetrator who commits just one crime, so combined punishments for several offenses should be applied to the real concurrence of offenses.

The principle of choosing the most severe punishment applied to the real concurrence of offense should be abolished. As the perpetrator separately conducts two acts at different times, these acts infringe on different legal interests. Although these acts exist closely, the authors cannot deny that these acts constitute more than one offense.

The structure and protective effect of Al-coated Nd-Fe-B magnets before and after grain boundary diffusion were studied to explore the feasibility of improving the corrosion resistance of Nd-Fe-B magnets by Al coating and Al grain boundary diffusion.

The Al coating was deposited on sintered Nd-Fe-B magnets by magnetron sputtering, and then the Al-coated Nd-Fe-B magnets were put into the vacuum tube furnace for grain boundary diffusion process. The influence of Al coating and grain boundary diffusion process on the corrosion resistance of Nd-Fe-B magnets was investigated using electrochemical tests.

Results showed that the Al coating thickness increases, the corrosion current density of Al-coated magnets first increases and then decreases with increasing coating time. The Al coating particles transform from small millet shaped particles to equiaxed polygonal particles, and finally to big millet shaped particles with increasing coating time. The diffusion temperature has little effect on the corrosion potential, and the corrosion current density of Al-diffused magnets after grain boundary diffusion is much higher than that of Al-coated magnets before grain boundary diffusion. The corrosion potential and corrosion current density of magnets first increase, and then decrease with increasing tempering temperature.

As for high intrinsic coercivity Nd-Fe-B magnets, Poor preparation of Al coatings can result in Al coatings lacking protective properties, and the Al coating should be used cautiously as the surface protective coating of magnets. Grain boundary diffusion leads to the disappearance of Al coating, and reduces the corrosion resistance of Nd-Fe-B magnets, while tempering treatment can improve the corrosion resistance of Al-diffused magnets.