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The purpose of this paper is to search the optimal arrangement scheme of random motion accuracy of joints for optimal synthesis of pose repeatability which can make robot design more reasonable and reduce the development cost of robots.

In this paper, a mathematical model of pose repeatability, which includes positioning repeatability and orientation repeatability of robots, is established. According to the ISO 9283 standard, an optimal synthesis method of pose repeatability for collaborative robots is introduced, and three optimization objective functions are proposed. The optimization model is solved by using numerical analysis software, and the optimal arrangement scheme of random motion accuracy of joints is obtained which meets the requirements of pose repeatability of robot.

It is found that, in three optimization objective functions, the single-objective evaluation function of maximization of joint motion error is more suitable for optimal synthesis of pose repeatability. In practice, due to the safety factor, the test results of pose repeatability are better than the results of optimal synthesis of pose repeatability.

This method makes robot design more reasonable and reduces the development cost of robots.

This work is the first time to optimize the orientation repeatability of collaborative robots. Because the pose repeatability of most robots is tested by the ISO 9283 standard, so this method which is based on this standard is more suitable for the performance requirements of robot products.

The paper aims to reduce the low-frequency resonance and residual vibration of the robot during the operation, improve the working accuracy and efficiency. A reduced weight and large load-to-weight ratio can improve the practical application of a collaborative robot. However, flexibility caused by the reduced weight and large load-to-weight ratio leads to low-frequency resonance and residual vibration during the operation of the robot, which reduces the working accuracy and efficiency. The vibrations of the collaborative robot are suppressed using a modified trajectory-planning method.

A rigid-flexible coupling dynamics model of the collaborative robot is established using the finite element and Lagrange methods, and the vibration equation of the robot is derived. Trajectory planning is performed with the excitation force as the optimization objective, and the trajectory planning method is modified to reduce the vibration of the collaborative robot and ensure the precision of the robot terminal.

The vibration amplitude is reduced by 80%. The maximum torque amplitude of the joint before the vibration suppression reaches 50 N·m. After vibration suppression, the maximum torque amplitude of the joint is 10 N·m, and the resonance phenomenon is eliminated during the operation process. Consequently, the effectiveness of the modified trajectory planning method is verified, where the vibration and residual vibration in the movement of the collaborative robot are significantly reduced, and the positioning accuracy and working efficiency of the robot are improved.

This method can greatly reduce the vibration and residual vibration of the collaborative robot, improve the positioning accuracy and work efficiency and promote the rapid application and development of collaborative robots in the industrial and service fields.

This chapter examines the changing state–university–student relationships in post/socialist China since the late 1980s. We begin with an introduction to four salient themes in scholarship on Chinese post/socialism that are highly relevant to higher education: globalization, gradualism, civic society, and a critique of holism. These themes help us explain interrelated educational trends that affect the state–university–student relationship: the globalization, “massification,” and stratification of higher education; the redefined role of the state in university governance and management; higher education marketization and privatization; and the quest for meaning and (e)quality in and through higher education. Our general argument is that during the “socialist” period the main relationship central to higher learning was between the state and students. Universities were agents of the state; from a legal point of view, indeed, universities did not have an independent status from the state. In the “post-socialist” era the university–student relationship has become more significant. We examine this reconfiguration through two case studies, one on the development of college student grievance and rights consciousness, and the other on reforms in higher education student services administration. When looked at from the point of view of the state, we see that appropriation and implementation of policies and regulations shaping student rights and services are in partial contradiction with state policies to accelerate economic growth and bolster party authority. From the point of view of universities, we see institutions grappling with how to deliver on forward-looking structures and actions while navigating between the state's policy mandates and growing expectations and demands of its student and business stakeholders. From the point of view of students, we see how constrained agency, uncertainty, and the power of the credential motivates social praxis. At all levels of the state–institution–student relationship actors are employing a kind of pragmatic improvisation (one of the salient features of post/socialism) captured by the well-known Chinese proverb “groping for stones to cross the river.” This saying is an apt metaphor for the tentative searching by state, institution, and individual for a safe foothold in the post/socialist world.

The purpose of this paper is to develop a novel type of full‐size flight control iron bird based on a passive electronic hydraulic servo loading system.

On the basis of mathematical modeling of passive loading system math model, the detailed design process of the flight control iron bird is presented. Subsequently, the system digital simulation and physical verification are also given.

Experimental results show that the proposed approach can reduce the redundant forces and improve the system dynamic and force‐tracking accuracy.

This newly‐developed flight control iron bird system has been successfully applied in the flight control system design of some fighters.

The proposed approach for flight control iron bird is new and significant for the design of fighter flight control systems.

The purpose of this paper is to analyze volatility transmission between the Japanese stock and foreign exchange markets.

In contrast to the existing literature, industry‐level stock data are applied to a trivariate Baba, Engle, Kraft and Kroner‐generalised autoregressive conditional heteroscedasticity (BEKK‐GARCH) model that also includes comparable US industrial stocks returns as a control variable.

Using daily data over the study period 1994‐2007, it was found that news shocks in the Japanese currency market account for volatility transmission in eight of the ten industrial sectors considered. Evidence was also found of significant asymmetric effects in five of these industries.

While the BEKK‐GARCH model enables analysis of volatility transmission between the stock and foreign markets against a background of conditional correlation and asymmetries, the model requires the estimation of a large number of parameters, which can be problematic for a limited dataset.

The paper's findings have important implications for understanding international volatility transmission involving the stock and foreign exchange markets. This in turn can provide insight into investor behaviour.

This study aims to evaluate the thermal performance of phase change materials (PCMs) microcapsules (MCs) attached using SiO₂ microspheres and investigate the thermal regulation effect on the coated denim fabric.

The PCM microcapsule was prepared by in situ polymerization using a mixture of solid paraffin and butyl stearate as core material (CM) and methyl methacrylate as a monomer. The SiO₂ microparticles were attached to the outer layer of the membrane to enhance the thermal performance of MCs. The morphology, chemical structure, latent heat storage and thermal resistance of MCs were characterized. PCM MCs were coated on the denim fabric and thermo-gravimetric analysis was conducted; thermal insulation and thermal infrared imaging performance of the coated fabrics were also investigated.

The diameters of SiO₂ particles and PCMs MCs were 300-500 nm and 1 μm, respectively. SiO₂ was wrapped on single-wall PCMs MCs with the mass ratio of 1:5. With the addition of SiO₂, the phase transition temperature range of MCs increased from 34°C to 39°C, and the endothermic and exothermic latent heat decreased by 5.35 J/g and 10.07 J/g, respectively. The degradation rate of MCs was significantly slowed down at high temperature. The denim fabric coated with MCs revealed thermal regulation property. After absorbing heat, the MCs slowed down the rate of heat loss and extended the heat release time.

The phase transition temperature of the composite CM was wide, and the latent heat storage was reduced. The addition of SiO₂ particles can significantly slow down the rate of heat loss, but it further reduces the latent heat storage performance.

The method developed provided a simple and practical solution to improve the thermal regulation performance of fabrics.

The method of adjusting the phase transition temperature range of the composite CM is novel and many applications could be found in preparation of PCMs and thermal management.

Simulation is a well-known technique for using computers to imitate or simulate the operations of various kinds of real-world facilities or processes. The facility or process of interest is usually called a system, and to study it scientifically, we often have to make a set of assumptions about how it works. These assumptions, which usually take the form of mathematical or logical relationships, constitute a model that is used to gain some understanding of how the corresponding system behaves, and the quality of these understandings essentially depends on the credibility of given assumptions or models, known as VV&A (verification, validation and accreditation). The main purpose of this paper is to present an in-depth theoretical review and analysis for the application of VV&A in large-scale simulations.

After summarizing the VV&A of related research studies, the standards, frameworks, techniques, methods and tools have been discussed according to the characteristics of large-scale simulations (such as crowd network simulations).

The contributions of this paper will be useful for both academics and practitioners for formulating VV&A in large-scale simulations (such as crowd network simulations).

This paper will help researchers to provide support of a recommendation for formulating VV&A in large-scale simulations (such as crowd network simulations).

Science and technology innovation policy has important strategic significance with respect to the promotion of an innovation orientation in our country, and the classification and measurement of regional science and technology innovation policy urgently require research attention.

In this paper, we use text mining and principal component analysis to analyze the classification and measurement of technology innovation policy based on data obtained from Zhongguancun Science Park.

The empirical results indicate that regional science and technology innovation policy can be divided into four types: authoritative, guiding, urgent and periodical. The key measurements are function type, intensity, resource supply, funding level and funding effectiveness.

A comparative analysis is performed to investigate the different types of regional science and technology innovation policy measurement. Additionally, the study’s limitations are discussed, and future research directions are proposed.