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The purpose of this study is to improve the global optimization ability of the Tabu search (TS) algorithm, and then improve the calculation efficiency and accuracy of rolling schedule in tandem cold rolling.

A case-based reasoning–Tabu search hybrid algorithm (CBRTS) has been presented. First, the case-based reasoning technology was adopted to obtain high-quality initial solution and then the TS algorithm was used for global optimization.

The optimization effect of CBRTS is compared with that of the traditional TS algorithm, and the analysis result indicates that the CBRTS has a faster convergence rate than TS, and the optimization results are closer to the global optimal. Meanwhile, the rolling schedule calculated by CBRTS is more reasonable, which can increase the production efficiency while giving full play to the capacity of equipment.

A CBRTS hybrid algorithm is presented. The strong dependence of the TS algorithm on the initial solution has been solved. The rolling schedule multi-objective optimization functions are established. The proposed algorithm is applied in a 1,450-mm tandem cold rolling production line. The improved method can reduce about half the iterations compared with the traditional one.

The purpose of this paper is to reduce the carbon footprint of food by adjusting the international trade and planting structure and to provide possible ideas for the improvement of the world's food green production and green trade.

Using the literature analysis method to collect carbon footprint data calculated based on the life cycle assessment (LCA) method, and establishing an optimization model and an ARIMA prediction model for empirical analysis, this paper explores the possibility to reduce carbon emissions by adjusting import structure and self-production structure.

The results show that only through the adjustment of the import structure, carbon emissions can be reduced by 3.29 million tons at the source of imports. When domestic self-production is included, a total of 4.51 million tons of carbon emissions can be reduced, this provides ideas for low-carbon emission reduction in agriculture and animal husbandry.

This article is the first to use the carbon footprint data obtained by other scholars using LCA to optimize and analyze the grain trade structure and planting structure from a low-carbon perspective, and obtain specific emission reductions.

The influence of Zn concentration on microstructure and corrosion performance of the Mg–xZn alloys microalloyed with Ca and Ce was investigated through optic microscopy, scanning electron microscopy, hydrogen evolution, dynamic polarization and electrochemical impedance spectroscopy experiments.

In this paper, Mg–xZn alloys (x = 0.5∼2.0 Wt.%) microalloyed with Ca and Ce (0.2 Wt.% each) were prepared.

As the increase of Zn concentration, the number of second phase particles (Mg-Zn-Ca, Mg-Zn-Ce and Mg-Ce phases) increased, and when the Zn concentration increased to 2.0 Wt.%, the new second phase Mg-Zn phase was precipitated.

The influence of Zn concentration on corrosion mechanism of Mg-xZn alloys microalloyed with Ca and Ce was revealed. Increasing of the Zn concentration resulted in the intensification of galvanic corrosion. When Zn concentration was 0.5 Wt.%, the alloy showed the lowest corrosion rate (0.61 mm y-1), which was about 1/2 of that of Mg-2.0Zn-0.2Ca-0.2Ce alloy.

In the process of cold rolled strip, there is tight coupling between flatness control and gauge control. The variation of the roll gap caused by the change of bending force will lead to the change of rolling force. Furthermore, it can cause a deep impact on the control accuracy of strip exit thickness and exit crown. The purpose of this paper is to improve the accuracy of the bending force preset value for cold rolled strip.

In this paper, the bending force preset control strategy with considering of rolling force was proposed for the first time and the preset objective function of bending force was established on the basis of the two-objective optimization of bending force and rolling force. Meanwhile, the multi-objective intelligent algorithm – INSGA-II – was used to solve the objective function.

The proposed bending force multi-objective preset model has been tested in a 1,450 mm tandem cold rolling line. The analyzed results of field data show that the deviations of strip exit thickness and exit crown are reduced effectively by using the improved model, and at the same time, more reasonable bending force preset values are obtained, which can enhance the accuracy of flatness preset control.

A preset model of bending force with considering flatness and gauge is proposed in this paper and the multi-objective function of bending force preset is established on the basis of the two-objective optimization of bending force and rolling force. The value lies in proposing a new decoupling method of rolling force and bending force.

The purpose of this study is to investigate the effects of capital market liberalization on audit reporting and pricing. The authors use the announcement of the Shanghai-Hong Kong Stock Connect program in China as a shock to capital market liberalization.

The authors use the difference-in-differences method to study the difference in changes in the frequency of modified audit opinions and audit fees between the treatment group and the control group.

This study finds that capital market liberalization increases reputational and litigation risks for auditors and leads to more conservative audit reports. In addition, capital market liberalization stimulates the management of eligible firms to improve the information environment, helps to reduce information asymmetry and decreases audit fees. Specifically, the authors identify the channels of active foreign institutional investors as a new governance mechanism through which capital market liberalization impacts eligible firm and auditor decisions.

This study complements the literature by showing that capital market liberalization may bring a new and strong governance mechanism for eligible firms and auditors.

This study may provide new references for active foreign institutional shareholders as a new and strong governance mechanism in weak institutional regimes such as China, auditors’ optimization decisions when litigation risks increase and management’s improvements in the information environment under the monitoring of foreign institutional shareholders.

Overall, this study contributes to the literature by showing that capital market liberalization can bring a new governance mechanism for the management of eligible firms and auditors in a weak institutional environment. Foreign institutional shareholders may be superior to the domestic market forces and other corporate governance in the role of monitoring the management of eligible firms and auditors.

The purpose of this paper is to study the influence of friction coefficient of materials with different elastic modulus on the variation of velocity and load under water lubrication and oil lubrication conditions.

Low-viscosity lubricating oil and water were used as lubricants to test the friction performance of the ball-disc contact friction pair in the lubrication state on the universal micro-tribometer multi-functional friction and wear test system.

In the same speed range, the lubrication states from soft to rigid materials are not necessarily similar to each other. Generally, the material with low elastic modulus is suitable in low-viscosity lubricant environments, while the material with high elastic modulus has relatively smaller friction coefficients in oil-lubricated environments compared with water lubrication. However, the coefficients of polyethylene, polytetrafluoroethylen and polyoxymethylene are exceeded by rubber’s coefficients under water lubrication in the same experiment environments, and their lubrication states are not affected by lubricants. The friction coefficient of the friction pair decreases with the increase of loads; however, it does not apply to all materials. The friction coefficients of materials with smaller elastic modulus such as rubber under high loads are rather large. Therefore, the elastic modulus of the material under high loads is a factor to be considered.

The Stribeck curves study of the ball-disk contact friction pair comprising soft and rigid materials, whose elastic modulus is from hundreds of GPa to a few of MPa, was carried out. The influence of different speeds, loads and lubricants on the friction coefficient of the friction pair was revealed, which provided a research basis for the selection and matching of friction pair materials.

To implement a risk-based regulatory approach, this paper aims to make an assessment on customers' money laundering risk and conducts some applications.

During the transition of a regulatory approach from “rule-based” to “risk-based”, this paper considers that the area of a customer, types of business and the industries to which the customer belongs are the main indicators to judge money laundering risk of a customer. Based on the statistical analysis of 221 typical money laundering cases, first-class index weights are given by using the entropy weight method and then by combining with the membership function, this paper determines a customer’s money laundering risk levels. On the basis of the entropy weight method, this paper uses the C5.0 algorithm to construct a decision tree model and then carries out application research on customer money laundering risk assessment to verify the effectiveness of the entropy weight method and the decision tree model.

This empirical research found the weights of three key money laundering indicators: customer areas, business types and corresponding industries.

Asserting that current money laundering risk assessments of customers are marginal at best, this paper contends from the perspective of practice, and applies the entropy weight method and the decision tree model for money laundering risk assessment of customers.

This paper aims to present a method to improve the sensitive and low probabilities of false alarm of a manipulator in a human–robot interaction environment, which can improve the performance of the system owing to non-linear uncertainty in the model of the robot controller.

A novel collision detection method based on adaptive residual estimation is proposed, promoting the detection accuracy of the collision of the manipulator during operation. First, a general momentum residual estimator is designed to incorporate the non-linear factors of the manipulator (e.g. joint friction, speed and acceleration) into the residual-related uncertainty of the model. Second, model parameters are estimated through gradient correction. The residual filter is used to determine the dynamic threshold, resulting in higher detection accuracy. Finally, the performance of the residual estimation scheme is evaluated by comparing the dynamic threshold with residual in real-time experiments where a single Universal Robot 5 robot end–effector collides with the obstacle.

Experimental results demonstrate that the collision detection system can improve sensitivity and lead to low probabilities of false alarm of non-linear uncertainty in the model.

The method proposed in this article can be applied to industry and human–robot interaction area.

An adaptive collision detection method is proposed in this paper to address non-linear uncertainties of the model in industrial application.

The purpose of this paper is to differentiate between intra- and inter-regional diversification and explore how each affects firm performance. Existing studies show that both intra- and inter-regional expansion provide benefits and incur costs but the findings are mixed. This study aims to explain the mixed findings.

This study uses secondary data and quantitative methodologies to test hypotheses.

Using data from 663 Canadian firms over a six-year period (2006–2011), the authors find that the relationship between firm performance and the depth and width of intra-regional expansion is nonlinear. The authors also find a sigmoid-shaped relationship between firm performance and inter-regional diversification, i.e., performance initially increases with home regional diversification, decreases with bi-regional diversification and finally increases again with multi-regional diversification.

The findings of this study shed light on the current debate on the merits of inter- and intra-regional diversification and have important theoretical and managerial implications.

This study aims to improve the welding quality and efficiency, and an algorithm should be designed to realize tracking space-curved fillet weld joints.

Fillet weld joints tracking based on the two wheels and the horizontal slider coordinated movement has been studied. The method of pattern recognition is used to identify the height deviation, and the analysis of the accuracy corresponding to recognizing height deviations has been researched. The proportional control algorithm is used to control the vertical and horizontal sliders movement, so fillet weld joints tracking in the height direction has been achieved. Based on wheels and vertical and horizontal sliders coordinated movement, the algorithm of space-curved fillet weld joints tracking has been researched.

Some experiments have been done, and experimental results show that the welding robot can track space-curved fillet weld joints with high accuracy and good reliability.

The welding robot can improve the welding quality and efficiency.

The welding robot can track fillet weld joints in ship panels, and it was shown that the welding robot could track space-curved fillet weld joints with high accuracy and good reliability.

The welding robot has many industrial and social applications.

There are various forms of fillet weld joints in the industry, and the fillet weld is curved in the space. Experimental results show that the welding robot can track space-curved fillet weld joints with good stability and high precision.