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Technical advantages embraced by blockchain, such as distributed ledger, P2P networks, consensus mechanisms and smart contracts, are highly compatible with addressing the security issues of transferring and storing judicial documents and obtaining the feedback and evaluation of judicial translation services in cases with foreign elements. Therefore, based on this, a consortium blockchain-based model for supervising the overall process of judicial translation services in cases with foreign elements is proposed.

Some judicial documents are required to be translated when there are language barriers in cases with foreign elements. The purpose of this paper is expected to address security issues, which is ignored, in the process of translating judicial documents.

The experimental results show that the model constructed in this paper can effectively guarantee the security and privacy of transferring and storing translated judicial documents in cases with foreign elements, and realize the credibility and traceability of feedbacks and evaluations of judicial translation services. In addition, the underlying network communications is stable and the speed for processing data can meet the requirements of practical application.

The research in this paper provides an innovative scheme for judicial translation services in cases with foreign elements. The model constructed is conducive to protecting the security of the transfer and storage of judicial documents and improving the efficiency and modernization ability of hearing cases with foreign elements.

The purpose of this paper is to study the microstructure and mechanical behaviour of smaller microbumps for high density solder interconnects.

The microstructure was analyzed by scanning electron microscopy and electron backscatter diffraction tests to determine the Sn grain number of the resultant microbumps. The nanomechanical properties of Sn microbumps were investigated by the nanoindentation and shearing tests to understand the failure mechanism and assess the reliability of ultra-high density solder interconnects with numbered grains.

Only one Sn grain is observed in the interconnect matrix when the microbumps are miniaturized to 40 μm or less. Because of the body-centred tetragonal lattice of ß-Sn unit cell, the mechanical properties of the one-grain Sn microbumps are remarkably anisotropic, which are proved by the difference of the elastic modulus and the stiffness in the different orientations. The shearing tests show that the one-grain Sn microbump has a typical brittle sliding fracture of monocrystal at different shearing speeds.

The paper provides a comparable study for the performance of the bigger solder joints and also makes preliminary research on the microstructure and mechanical behaviour of Sn microbumps with the diameter of 40 μm.

The findings in this paper provide methods of microstructure study by combination of EBSD test and metallographic analysis, mechanical study by combination of nanoindentation test and shearing test, which can provide good guidelines for other smaller microbumps. The strain rate sensitivity exponent of the one-grain Sn microbumps is consistent with the Pb-free bulk solder. This implies that the one-grain Sn microbump has a comparable flow stress to Sn37Pb solder, which is beneficial for Pb-free replacement in higher density microelectronic packaging.

The purpose of this paper is to explore how social value orientation and domain knowledge affect cooperation levels and transcription quality in crowdsourced manuscript transcription, and contribute to the recruitment of participants in such projects in practice.

The authors conducted a quasi-experiment using Transcribe-Sheng, which is a well-known crowdsourced manuscript transcription project in China, to investigate the influences of social value orientation and domain knowledge. The experiment lasted one month and involved 60 participants. ANOVA was used to test the research hypotheses. Moreover, inverviews and thematic analyses were conducted to analyze the qualitative data in order to provide additional insights.

The analysis confirmed that in crowdsourced manuscript transcription, social value orientation has a significant effect on participants’ cooperation level and transcription quality; domain knowledge has a significant effect on participants’ transcription quality, but not on their cooperation level. The results also reveal the interactive effect of social value orientation and domain knowledge on cooperation levels and quality of transcription. The analysis of the qualitative data illustrated the influences of social value orientation and domain knowledge on crowdsourced manuscript transcription in detail.

Researchers have paid little attention to the impacts of the psychological and cognitive factors on crowdsourced manuscript transcription. This study investigated the effect of social value orientation and the combined effect of social value orientation and domain knowledge in this context. The findings shed light on crowdsourcing transcription initiatives in the cultural heritage domain and can be used to facilitate participant selection in such projects.

The purpose of this paper is to design a new type of magnetic suction wall-climbing robot suitable for the wall inspection of wind turbine towers to solve the problems in manual maintenance tasks.

By analyzing the shortcomings of existing wall-climbing robots, a magnetic suction integrated wheel structure is designed to effectively combine the adsorption structure and transmission structure. To enable the robot to adapt to the curvature of the wall surface of a wind turbine tower, a passive adaptive curvature structure is designed. The effects of the air gap, the thickness of the wheel plates on both sides, the size of permanent magnets and the size of aluminum rings on the adsorption force are studied. Through mechanical model analysis under different instability conditions, the magnetic circuit of the magnetic wheel is optimized and designed.

Applying the wall-climbing robot to engineering practice, experiments have shown that the developed wall-climbing robot can move safely and stably on the wall of the wind turbine tower. The robot can also carry a load of 20 kg, and the designed adaptive structure can cause the magnetic wheel to deflect up to 20° relative to the vehicle body, fully meeting the curvature requirements of the minimum diameter end of the wind turbine tower.

This paper proposes a magnetic suction integrated wheel structure through analysis of the working environment. And the parameters affecting the magnetic wheel adsorption performance were optimized. Meanwhile, a passive adaptive wind turbine tower curvature structure was proposed.

High residual stress caused by the high temperature gradient brings undesired effects such as shrinkage and cracking in selective laser melting (SLM). The purpose of this study is to predict the residual stress distribution and the effect of process parameters on the residual stress of selective laser melted (SLMed) Inconel 718 thin-walled part.

A three-dimensional (3D) indirect sequentially coupled thermal–mechanical finite element model was developed to predict the residual stress distribution of SLMed Inconel 718 thin-walled part. The material properties dependent on temperature were taken into account in both thermal and mechanical analyses, and the thermal elastic–plastic behavior of the material was also considered.

The residual stress changes from compressive stress to tensile stress along the deposition direction, and the residual stress increases with the deposition height. The maximum stress occurs at both ends of the interface between the part and substrate, while the second largest stress occurs near the top center of the part. The residual stress increases with the laser power, with the maximum equivalent stress increasing by 21.79 per cent as the laser power increases from 250 to 450 W. The residual stress decreases with an increase in scan speed with a reduction in the maximum equivalent stress of 13.67 per cent, as the scan speed increases from 500 to 1,000 mm/s. The residual stress decreases with an increase in layer thickness, and the maximum equivalent stress reduces by 33.12 per cent as the layer thickness increases from 20 to 60µm.

The residual stress distribution and effect of process parameters on the residual stress of SLMed Inconel 718 thin-walled part are investigated in detail. This study provides a better understanding of the residual stress in SLM and constructive guidance for process parameters optimization.

Using the Shanghai pilot free trade zone (SPFTZ) as the testing ground for further reform and opening up,the links between global value chain (GVC) and pilot free trade zone (PFTZ) programs are mutually reinforcing. GVC creates opportunities for companies to use PFTZ to reduce their costs and increase their competitiveness, while PFTZ can facilitate the movement of goods within GVC and promote the development of GVC by attracting foreign investment. Overall, in SPFTZ, the industrial structure is promoted due to trade and investment facilitation, innovation promotion, and comprehensive service platform inside SPFTZ.

This study examined industrial upgrading in GVC (IUGVC) using five indicators under three quantitative dimensions: product, process, and skill upgrading. Difference-in-Differences (DID) model is employed for the impact assessment of SPFTZ. Parallel trend analysis and Granger causality analysis are performed to check the reliability of DID outcome. Finally, robustness test using exogenous control variables are carried out.

A positive impact of SPFTZ is found on IUGVC, which is due to promoting effect of SPFTZ on foreign direct investment and technological innovation. Based on the study's findings, policy recommendations are given, such as providing business support to enterprises operating inside a PFTZ.

From a GVC perspective, the impact of theSPFTZ establishment on IUGVC cannot be ignored, and is so far missing in the literature.

This paper aims to present a control method to realize the constant force grinding of automobile wheel hub.

A constant force control strategy combined by extended state observer (ESO) and backstepping control is proposed. ESO is used to estimate the total disturbance to improve the anti-interference and stability of the system and Backstepping control is used to improve the response speed of the system.

The simulation and grinding experimental results show that, compared with the proportional integral differential control and active disturbance rejection control, the designed controller can improve the dynamic response performance and anti-interference ability of the system and can quickly track the expected force and improve the grinding quality of the hub surface.

The main contribution of this paper lies in the proposed of a new constant force control strategy, which significantly improved the stability and precision of grinding force.

This study considers the “technology creation” characteristic of technical knowledge-intensive business services (T-KIBS) and examines how human capital and intellectual property rights (IPR) protection affect the location choice of foreign direct investment (FDI) in China for two types of T-KIBS: (1) information transmission, software and information technology (ICT) services and (2) scientific research and technology (SCI) services.

Our empirical analysis is based on panel data on 22 Chinese provinces from 2009 to 2017. We use the generalized method of moments estimation for the regression analysis.

FDI in ICT services prefers regions with high human capital, while FDI in SCI services favors regions with good IPR protection.

Future research could use more comprehensive data and qualitative interviews to enhance the findings.

These findings provide a foundation for China’s future policy on attracting FDI into T-KIBS, especially in areas related to human capital and IPR protection.

This study bridges the research gap on the FDI location choice of T-KIBS in China by clarifying the influences of human capital and IPR protection and providing theoretical support for the location choice of T-KIBS FDI.

Considering the response lag and viscous slip oscillation of the system caused by cylinder piston friction during automatic polishing of aero-engine blades by a robotic pneumatic end-effector, the purpose of this study is to propose a constant force control method with adaptive friction compensation.

First, the mathematical model of the pneumatic end-effector is established based on the continuous LuGre model, and the static parameters of the LuGre model are identified to verify the necessity of friction compensation. Second, aiming at the problems of difficult identification of dynamic parameters and unmeasurable internal states in the LuGre model, the parameter adaptive law and friction state observer are designed to estimate these parameters online. Finally, an adaptive friction compensation backstepping controller is designed to improve the response speed and polishing force control accuracy of the system.

Simulation and experimental results show that, compared with proportion integration differentiation, extended state observer-based active disturbance rejection controller and integral sliding mode controller, the proposed method can quickly and effectively suppress the polishing force fluctuation caused by nonlinear friction and significantly improve the blade quality.

The pneumatic force control method combining backstepping control with the friction adaptive compensation based on LuGre friction model is studied, which effectively suppresses the fluctuation of normal polishing force.

Considering the influence of environmental noise and modeling error during the process of the robotic automatic grinding aero-engine blade, this study aims to propose a method based on the extended state observer (ESO) to reduce the fluctuation of normal grinding force.

First, the measurement range of the six-dimensional force sensor is calibrated according to the maximum acceleration of end-effector and grinding force. Second, the gravity and zero drift compensation model is built to compensate for measurement error. Finally, the switching function is designed based on the difference between the expected grinding force and the actual feedback value. When the value of function stays within the switching band, a nonlinear active disturbance rejection control (ADRC) loop is applied. When the function value reaches outside the switching band, an ESO-based sliding mode control (SMC) loop is applied.

The simulated and experimental results show that the proposed control method has higher robustness compared with proportion-integral-derivative (PID), Fuzzy PID and ADRC.

The processing parameters of this paper are obtained based on the single-factor experiment without considering the correlation between these variables. A new control strategy is proposed, which is not only used to control the grinding force of blades but also promotes the development of industrial control.

ESO is used to observe environmental interference and modeling errors of the system for real-time compensation. The segment control method consisting of ESO-based SMC and ESO-based ADRC is designed to improve the robustness. The common application of the two parts realizes suppression of fluctuation of grinding force.