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The purpose of this research is to achieve a novel magnetic nutation drive for an industry robotic wrist reducer.

A novel magnetic nutation drive is proposed, and the structure and principle of the designed magnetic nutation drive are described in this study. Three-dimensional finite element analysis is used to compute the magnetic and torque of the magnetic nutation drive. Furthermore, a prototype of this novel magnetic nutation drive device is developed with 3D printing technology and tested to verify the feasibility of the proposed structure and principle.

The simulation and experimental results indicated that the proposed magnetic nutation drive device could meet the desired specifications, and that this novel magnetic nutation drive device successfully realized the non-contact transmission ratio of 105:1 required for a robotic wrist reducer.

This novel magnetic nutation drive is low-cost and easy to make and use, and which provides the non-contact transmission ratio of 105:1 required for a robotic wrist reducer.

For the first time, this research applies the permanent magnet drive technology to nutation drive and puts forward a new non-contact nutation drive mode. The novel drive mode can solve some problems of the traditional mechanical contact nutation drive, such as vibration, friction loss, mechanical fatigue and necessity of lubrication. The proposed non-contact nutation drive device can achieve a high reduction ratio with compact structure and can be suitable for industry application.

The current literature lacks discussion on the effects of synergy among multiple factors at different levels on foreign subsidiary performance. The purpose of this paper is to explore the configuration of factors affecting foreign subsidiary performance.

The methodology adopted in this paper is the fuzzy-set qualitative comparative analysis (fsQCA). The data are obtained from 125 foreign subsidiaries of Chinese MNCs through questionnaire surveys and secondary data.

The research results reveal that five configurations of antecedent conditions predict high foreign subsidiary performance, and the other two configurations predict not-high performance.

This paper’s main limitation is its only focus on foreign subsidiaries of Chinese MNCs, which means that the findings should be generalized with precaution. The most valuable implication is to identify the configurations that lead to high and not-high foreign subsidiary performance.

This paper addresses the question of how interdependent factors at the national and corporate level are beneficial to foreign subsidiaries’ performance.

This study makes the following contributions to current theories: It provides (1) new insights for understanding the complex causality between antecedent conditions and foreign subsidiary performance and (2) a practical reference for the multinational operations of foreign subsidiaries.

The purpose of this paper is to investigate the impact of social and economic factors on home ownership as an investment in American urban areas.

The authors run a spatial analysis using home ownership data on 817 American counties from US Census Bureau’s 2013 American Community Survey.

While the amenity value of home ownership is found to be important to overall housing tenure decisions, it is found to be less so for the ownership cohort without mortgages. Economic factors are found to impact the spatial pattern of owner-occupied housing without mortgage differently than that of all owner-occupied housing. The implications of these differences for investors are explored.

The results may lack generalizability outside of the American urban areas.

As a result of the findings of this study, a shift in investor focus from minimizing initial housing costs to sustainable housing costs is recommended.

This study provides insights into the social and economic dimensions of owner-occupied housing in order to create a more profitable investing policy for promoting home ownership.

In recent years, hotels in China have been interested in leveraging social media platforms to facilitate interactions with and among consumers. Such brand engagement efforts on social media networks are believed to promote brands through co-creation of consumer experiences and values. This study was conducted in the context of Chinese hotels. The paper aims to identify two forms of brand engagement via social media platforms – consumer-initiated engagement and firm-initiated engagement – and to examine their effects on hotels’ display advertising effectiveness.

This study collected a comprehensive data set. First, the authors collected display advertisement data from two hotel chains in China. Second, the authors gathered the two hotels’ engagement data from Weibo. A generalized linear mixed model was used in data analysis.

The findings of the study indicate that both forms of brand engagement on social media network sites positively influence display advertising effectiveness. Moreover, for a strong brand, consumer-initiated engagement is more influential in increasing display advertising effectiveness; however, for a weak brand, firm-initiated engagement gains more clicks and conversions from advertisements.

As hotels in China continue to leverage online media platforms to reach, engage with and co-create value with potential and existing consumers, this study provides managers with insight as to how they can achieve higher advertising effectiveness by engaging with consumers on a consistent basis on social media.

This study mainly contributes to recent increasing research on engagement and value co-creation by providing a lens through which to assess the relationship between brand engagement via social media networks and online display advertising effectiveness.

Ultra-high molecular weight polyethylene (UHMWPE) is adopted in water-lubricated bearings for its excellent performance. This paper aims to investigate the tribological properties of UHMWPE with a molecular weight of 10.2 million (g mol^‐1) under different molding temperatures.

The UHMWPE samples were prepared by mold pressing under constant pressure and different molding temperatures (140°C, 160°C, 180°C, 200°C, 220°C). The friction and wear tests in water were conducted at the RTEC tribo-tester.

The friction coefficient and wear loss decreased first and rose later with the increasing molding temperature. The minimums of the friction coefficient and wear loss were found at the molding temperatures of 200°C. At low melting temperatures, the UHMWPE molecular chains could not unwrap thoroughly, leading to greater abrasive wear. On the other hand, high melting temperatures will cause the UHMWPE molecular chains to break up and decompose. The optimal molding temperatures for UHMWPE were found to be 200°C.

Findings are of great significance for the design of water-lubricated UHMWPE bearings.

This paper aims to evaluate the corrosion resistance of fusion zones in different heat treated condition from laser welded Mg-Gd-Y alloys and analyze their intrinsic corrosion mechanism.

The corrosion behavior of fusion zone from laser-welded Mg-Gd-Y alloy joints in the as-welded, ageing and solution + ageing conditions was investigated in the 3.5 wt.% NaCl solution by immersion tests.

The corroded surface of as-welded fusion zone consists of dark and bright regions, and the bright regions were composed of high-density needle-like products, whereas some different extended direction of the cracks with lots of long ultrafine needle-shaped corrosion products appeared in the dark regions. The corrosion resistance of the fusion zone is slightly decreased after the ageing treatment.

The solution + ageing treated fusion zone exhibits the highest corrosion resistance than that of the as-welded and ageing treated state because of the full dissolution of the cathodic coarse eutectic compound, grains growth and relatively compact protective films. The inhomogeneous distribution of the β′ can somewhat improve the corrosion rate of solution + ageing treated fusion zone when compared with base metal.

The purpose of this study was to investigate the tribological properties of bulk Fe₂B with pre-oxidation treatment.

Bulk Fe₂B was oxidized in an electric box furnace with a soaking time of 9 min under 750°C in air. Then, the tribological experiments were carried out on an UMT-Tribolab tester.

The oxide layer was composed of Fe, Fe₂O₃, Fe₃O₄, B₂O₃ and H₃BO₃. The oxidative direction of bulk Fe₂B was perpendicular to the sample surface. But, the oxidative direction of Fe₂B crystals was irregular. At 0.1 m/s, the friction coefficient was the lowest. The effects of shortening the running-in period of friction and reducing the friction coefficient by pre-oxidation treatment at 0.1 m/s were remarkable. Nevertheless, the effect of pre-oxidation treatment was futile at 0.2 m/s. Wear mechanisms of oxidized Fe₂B mainly were adhesive and abrasive wear.

The effects of shortening the running-in period of friction and reducing the friction coefficient by pre-oxidation treatment were remarkable.

The purpose of this paper is to propose a novel strategy of optimal parameters configuration and placement for sensitive equipment.

In this study, clamped thin plate is considered as the foundation form, and a novel composite system is proposed based on the two-stage isolation system. By means of the theory of mechanical four-pole connection, the displacement amplitude transmissibility from the thin plate to precision equipment is derived. For the purpose of performing optimal design of the composite system, a novel multi-objective idea is presented. Multi-objective particle swarm optimization (MOPSO) algorithm is adopted as an optimization technique, which can achieve a global optimal solution (gbest), and selecting the desired solution from an equivalent Pareto set can be avoided. Maximum and variance of the four transmitted peak displacements are considered as the fitness functions simultaneously; the purpose is aimed at reducing the amplitude of the multi-peak isolation system, meanwhile pursuing a uniform vibration as far as possible. The optimization is mainly organized as a combination of parameter configuration and placement design, and the traversal search of discrete plate is performed in each iteration for the purpose of achieving the global optimum.

An important transmissibility based on the mechanical four-pole connection is derived, and a composite vibration isolation system is proposed, and a novel optimization problem is also defined here. This study reports a novel optimization strategy combined with artificial intelligence for parameters and placement design of precision equipment, which can promote the traditional view of two-stage vibration isolation.

Two-stage vibration isolation systems are widely applied to the vibration attenuation of precision equipment, but in these traditional designs, vibration participation of foundation is often ignored. In this paper, participation of foundation of equipment is considered, and a coherent new strategy for equipment isolation and foundation vibration is presented. This study shows a new vision of interdisciplinary including civil engineering, mechanical dynamics and computational science.

A number of automated tools will be required for the purpose of enabling efficient services in air traffic control. The purpose of this paper is to devise an optimal flight trajectory search method that optimizes airspace system efficiency for 3D space in the presence of uncertainties.

This paper put forward an optimization model for generating applicable solutions of multi-aircraft conflict resolution problem, and the solution is based on the principle of optimality.

The conflict resolution problem between multiple aircraft can be described by spatial discretization, and the approach taken digitizes the 3D space into a grid of nodes.

The simulation examples are given to illustrate the validity of trajectory search model and stress on the impact of different system parameters.

Realistic constraints that are convenient to operate are incorporated in the system model, and the results show that it can provide reliable decision-making for conflict avoidance.