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Recently, deep reinforcement learning is developing rapidly and shows its power to solve difficult problems such as robotics and game of GO. Meanwhile, satellite attitude control systems are still using classical control technics such as proportional – integral – derivative and slide mode control as major solutions, facing problems with adaptability and automation.

In this paper, an approach based on deep reinforcement learning is proposed to increase adaptability and autonomy of satellite control system. It is a model-based algorithm which could find solutions with fewer episodes of learning than model-free algorithms.

Simulation experiment shows that when classical control crashed, this approach could find solution and reach the target with hundreds times of explorations and learning.

This approach is a non-gradient method using heuristic search to optimize policy to avoid local optima. Compared with classical control technics, this approach does not need prior knowledge of satellite or its orbit, has the ability to adapt different kinds of situations with data learning and has the ability to adapt different kinds of satellite and different tasks through transfer learning.

Electrochromic window (ECW) has been gradually applied to building engineering in recent years. However, empirical study of this technology used in green building design is still lacking. This study aims to verify the lighting and energy-saving performance of ECW under a specific geographical environment.

The meditation pavilion of Jinwan new materials research institute in Zhuhai is taken for research object. Three kinds of sun-shading techniques, namely, ECW, Low-E window and ordinary glass window, with same specifications are selected as the building facade structure for simulation. Day lighting analysis, sun-shading performance and annual energy consumption are separately simulated in the same environment by the Autodesk Ecotect Analysis software. The energy-saving performance of ECW is obtained by comparisons.

Result shows that the shading performance of ECW is much better than ordinary window and Low-E window. When ECW is used in the east, west or top lighting interfaces of a building, about 40% of the total solar radiation can be reduced during daytime in summer. Taking the ordinary glass window as a basic reference, ECW can save about 90% of the annual energy consumption of the glass house. ECW can effectively reduce the annual refrigeration energy consumption of buildings in the subtropical region.

Reasonable use of ECW in the subtropical region can effectively reduce the annual energy consumption of buildings.

It is a precedent study to analyze the lighting performance and energy consumption of a glass house with ECW. The energy-saving characteristics and beautiful appearance of ECW shall make it a future green building technology.

The strength of printed parts by application of fused deposition modeling (FDM) has been broadly studied through experimental methods. However, constitutive behaviors of the printed parts in theory are still unclear. Therefore, this paper aims to focus on building an elasto-plastic model of the printed parts to reveal the constitutive behavior.

An elasto-plastic constitutive model that considers anisotropic characteristics is proposed. Tensile tests are performed for parameter identification by using different samples with varying printing angles. Finally, the constitutive model is completed and applied to the numerical analysis of a tensile procedure.

The experimental study indicated that the anisotropic characteristics are significant for elastic modulus and strength of printed parts. The polar anisotropic model is suitable for describing the anisotropic behavior of parts during the elastic deformation. The Hill model is suitable to describe the yield property. The elastic modulus and yield point of parts printed in any specific orientation can be calculated using the proposed constitutive model.

A theoretical model has been developed to describe the constitutive behavior of FDM printed part. This model can precisely describe the elastic behavior and yield point of parts printed with various orientations. This model can be applied to the finite element simulation of printed structures.

The purpose of this paper is to study the operation performance of the high-speed ramjet kinetic energy projectile using solid fuel ramjet as power plant that is a new short-range and small caliber projectile.

The numerical investigation on combustion characteristic of polyethylene in high-speed ramjet kinetic energy projectile is carried out in this paper. The flow characteristics’ differences are analyzed when ramjet works or do not work, and both the combustion characteristics and propulsive performance are analyzed when ramjet works.

The results show that with the increase of the abscissa x, the flame front is close to solid fuel surface at first and then keeps away from solid fuel surface. With the increase of the abscissa x, the temperature of solid fuel surface and regression rate of solid fuel continues to increase before re-attachment point and then decreases, which a maximum locate at the re-attachment point. Both the average temperature and the regression rate on the surface of the solid fuel tend to rise as the increase of inflow Mach number. As the inflow of Mach number increases, the mass flow rate of gaseous fuel increases.

The research results can provide useful database for the subsequent research on high-speed ramjet kinetic energy projectile.

This paper studies the operation characteristics of the ramjet projectile, especially the effect of the change of the flight velocity on the performance of high-speed ramjet projectile.

This article aims to study unionisation of foreign companies in China and to evaluate its effectiveness on representing labour rights and interests, so as to explore the relationships between the Chinese unions and other industrial relations actors.

The article is based on in‐depth interview of key stakeholders from national, regional and company trade unions, as well as company management personnel. An archive study of union and company files is also conducted.

The Chinese trade union has realised that its interests stem from both the increase of membership dues and expansion of the membership base. Unionisation in transnational corporations (TNCs) is a key approach to achieve the interests of the union, which conducts grassroots mobilisation to counteract non‐operative companies but turns a blind eye on labour interest violations in collaborative firms. From the aspect of the union, the effectiveness of unionisation depends on raising its power leverage by affording fewer duties for the workers. Labour rights and workers' demands are not the structural concern of unionisation in TNCs.

The article challenges the research framework about Chinese unionism, which mainly emphasises a state‐union relationship or draws a corporatism perspective. The article concludes that the power relationship between the union and firm has acted as the key theme of the power struggle among industrial relations actors of China.

This paper investigates whether the audit fees of Chinese listed firms are associated with the share pledging practice of the firm’s controlling shareholders.

This study uses the audit pricing model to estimate the association between the share pledging of listed firms and audit fees. Cross-sectional analysis is conducted on a large sample of Chinese listed firms during the period 2004 to 2019. The authors further test the moderating effects of listing on the Main Board, state ownership and abnormal audit report lag on the association between share pledging and audit fees. The results remain robust to various endogeneity tests including two-stage least squares instrumental variable analysis, entropy balancing analysis and difference-in-difference analysis.

The study finds that audit fees are positively associated with the proportion of shares pledged by the listed firm’s controlling shareholder in China. The results also provide new evidence that the positive association between audit fees and the share pledging of controlling shareholders could be mitigated if the firm is listed on the Main Board and/or it is a state-owned enterprise. In contrast, pledged firms with abnormal audit report lag are found to have higher audit fees than their pledged counterparts without the excessively long audit delay.

Findings of this study have important practical implications to those charged with governance, as boards need to comprehensively understand the adverse consequences of share pledging when pursuing it as the firm’s major source of financing. The study also has policy implications for stock market regulators such as the China Securities Regulatory Commission in China. Regulators could consider developing a threshold-based share pledging disclosure and pledge ratio requirements based on factors such as a firm’s listing status and ownership structure.

This study provides new evidence on the audit-related consequences of share pledging in a significant capital market. Findings of this study also enrich the existing audit literature by introducing the share pledging activities of controlling shareholders into the audit pricing decision-making model.

The purpose of this paper is to study the effects of Cl⁻ and direct stray current on the soil corrosion of three grounding grid materials.

The electrochemical corrosion properties of three grounding grid materials, which include the Q235 steel, Q235 galvanized flat steel and copper, were measured by means of the weak polarization curve method and electrochemical impedance spectroscopy; the corrosion rate of specimens was calculated using the weight loss method; and the specimen surfaces were characterized using the scanning electron microscopy, energy-dispersive spectroscopy and X-ray diffraction analysis.

Results showed that both factors, Cl⁻ and direct stray current, can accelerate the corrosion rate of grounding grid materials. The magnitude of DC stray current density affected the mass transfer type and response frequency of the anode and cathode reaction of grounding materials, while the Cl⁻ contents of the soil only affect the mass transfer rate of the electrode material from the electrochemical impedance spectroscopy diagrams. The electric field generated by the DC stray current caused Cl⁻ directed migration. The larger the DC stray current density, the greater the diffusion process and the greater the weight loss rate of the grounding grid materials that would have a logarithmic relationship with the Cl⁻ content at the same DC stray current density. The corrosion resistance of the three materials is copper > Q235 galvanized flat steel > Q235 flat steel.

The paper provides information regarding the relationship among Cl⁻, direct stray current and corrosion of three grounding grid materials by means of electrochemical impedance spectroscopy. Meanwhile the weight loss rate is the logarithmic relationship with the Cl⁻ content, which is useful for understanding the corrosion mechanism of Q235 steel, Q235 galvanized flat steel and copper under the condition of Cl⁻ and direct stray current in soil.

Cosserat continuum models are motivated by modeling size effects in materials with micro-structure. While elastic Cosserat continuum models can reproduce size effects in deformation stiffness, inelastic models are often used to capture localization and post failure behavior of materials. In application of inelastic Cosserat models, parameter determination is a difficult issue not fully addressed. The purpose of this paper is to discuss parameter-related characteristic lengths in Cosserat continuum modeling of granular materials.

Based on a Cosserat continuum extension of a hypoplastic model for granular media, interpretation of additional parameters are sought through analysis of simple one-dimensional shear. Governing equations are obtained, respectively, for small strain shear formation and for stead flow state in localized zone.

Two characteristic lengths are obtained analytically for granular materials: one governs the size effect near boundaries in shear deformation, the other scales the thickness of shear band in failure. While both characteristic lengths are proportional to the micro-structure length (the mean grain diameter), the former is related to the micro-stiffness parameter, and the latter depends on the micro-strength parameter. The results reveal a connection between size effects, the micro-structure length and the material properties. The work also provides a new perspective to inelastic Cosserat continuum models, as well as a possible way for determination micro-deformation and strength parameters.

The results reveal a connection between size effects, the micro-structure length and the material properties. The work provides a new perspective and an interpretation to the micro-deformation and strength parameters of inelastic Cosserat continuum models, as well as a possible way for determination of these parameters.

This paper aims to present the first empirical liquidity measurement of China’s agricultural futures markets and study time-varying liquidity dependence across markets.

Based on both high- and low-frequency trading data of soybean and corn, this paper evaluates short-term liquidity adjustment in Chinese agricultural futures market measured by liquidity benchmark and long-term liquidity development measured by liquidity proxies.

By constructing comparisons, the authors identify the seminal paper of Fong, Holden and Trzcinka (2017) as the best low-frequency liquidity proxy in China’s agricultural futures market and capture similar historical patterns of the liquidity in soybean and corn markets. The authors further employ Copula-generalized autoregressive conditional heteroskedasticity models to investigate liquidity dependence between soybean and corn futures markets. Results show that cross-market liquidity dependence tends to be dynamic and asymmetric (in upper versus lower tails). The liquidity dependence becomes stronger when these markets experience negative shocks than positive shocks, indicating a concern on the contagion effect of liquidity risk under negative financial situations.

The findings of this study provide useful information on the dynamic evolution of liquidity pattern and cross-market dependence of fastest-growing agricultural futures in the largest emerging economy.

We reviewed U.S. federal and state sexual harassment court cases involving a prior workplace romance between the plaintiff and alleged harasser. Results of our content analysis show that, unlike employees’ decisions, judges’ decisions can be predicted from legal but not ethically salient extralegal case features. Hence, when compared to prior research, our study reveals the following discrepancy: judges follow a traditional legal model, whereas employees follow an ethical model when making decisions about romance‐harassment cases. Our study also reveals that the mere presence (versus absence) of a prior romance reduces the likelihood of a plaintiff’s success in a harassment case. We discuss implications for management practice and research from the perspective of legal and ethical decision making.