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This study aims to uncover the underlying mechanism between the time length of We-media videos and customer satisfaction (CS)/participation (CP) based on experiential marketing theory.

Two datasets were collected from Bilibili; 308 data were used with bootstrapping for multiple linear regressions (MLR) to test the hypotheses, and 2,670 data were used for structural equation modelling (SEM) to verify robustness.

Videos’ time length acts as both a price and provision element of experiential marketing. As a price element, its linear term affects CS negatively but CP positively. As a provision element, its quadratic term affects CS positively but CP negatively.

Marketing management personnel and video creators at Bilibili could optimise videos’ time length as suggested. We-media video platforms should encourage high-quality videos with sufficient time lengths to improve CS. Video creators could balance CS and CP, as suggested.

This research proposed platform, provision, price and propagation as experiential marketing elements concerning experiences in online virtual encounters. It found CS was affected positively by provision but negatively by price, whereas the opposite is true for CP. Time length affects CS/CP as both a price and provision element, which may explain the neglect of significant relationships between the time length and marketing performances of videos.

This paper aims to present a method of optimal singularity-free motion planning under multiple objectives and multiple constrains for the 6-DOF parallel manipulator, which is used as an execution mechanism for the automated docking of components.

First, the distribution characteristics of the Jacobian matrix determinant in local workspace are studied based on the kinematics and a sufficient and necessary condition of singularity-free path planning in local workspace is proposed. Then, a singularity-free motion path of the end-effector is generated by a fifth-order B-spline curve and the corresponding trajectories of each actuator are obtained via the inverse kinematics. Finally, several objective functions are defined to evaluate the motion path and an improved multi-objective particle swarm optimization algorithm-based on the Pareto archive evolution is developed to obtain the optimal singularity-free motion trajectories.

If the initial pose and the target pose of the end-effector are both singularity-free, a singularity-free motion path can be planned in the local workspace as long as all the values of each pose elements in their own directions are monotonous. The improved multi-objective particle swarm optimization (IMPSO) algorithm is effective and efficient in the optimization of multi-objective motion planning model. The optimal singularity-free motion path of the end-effector is verified in the component docking test. The docking result is that the movable component is in alignment with the fixed one, which proves the feasibility and practicability of the proposed motion path method to some extent.

The proposed method has a certain novelty value in kinematic multi-objective motion planning of parallel manipulators; it also increases the application prospect of parallel manipulators and provides attractive solutions to component assembly for those organizations with limited cost and that want to find an option that is effective to be implemented.

The purpose of this paper is to present the design and implementation of a new manipulator with six joints driven by a single DC motor.

The manipulator consists of several modules, each of which has the twisting and pivoting degrees of freedom. Two clutches and one brake are mounted to control each joint. A clutch model based on PWM control is built to compute the average velocity of each clutch. Two parameters are involved in the model: PWM frequency and duty ratio. PWM frequency is limited by the natural frequencies of structure with all postures. The theoretical duty ratio should be adjusted according to the clutch model. Two experiments – line tracking and arc tracking – are carried out to verify the effectiveness of the control system.

The study has designed a manipulator with six joints driven by a single DC motor which powers all the modules through a main shaft and several clutches. In the manipulator, all the modules are supplied with a constant speed input and provide a bi‐directional variable output. Experimental results show the clutch model built for the manipulator can be applied to the joint control of all multi‐joint manipulators.

The paper describes a dexterous and light‐weight manipulator driven by a single motor and designed with bi‐directional joints.

Extant research has paid considerable attention to the effects of enterprise social media (ESM) on employees' work attitudes and outcomes, yet the authors know little about the influence of job demands arising from the implementation of ESM. Drawing on resource allocation theory, the purpose of this study is to unravel how ESM-related job demands influence employee outcomes.

This study conducts a two-wave time-lagged survey of 223 employees from 53 teams in 14 financial service firms in China to test the conceptual model.

The findings of this paper indicate that ESM-related job demands have indirect effects on employee outcomes (i.e. job satisfaction and work–family conflict), and emotional exhaustion plays an intermediary role in these relationships. Specifically, ESM-related job demands have a U-shaped effect on emotional exhaustion.

This study combines job demands with ESM research and clarifies the mechanism behind how ESM-related job demands at different intensity affect employee outcomes from a new perspective. Moreover, this study’s findings suggest several beneficial courses of action for managers to take advantage of ESM.

The purpose of this paper is to investigate the mechanical behavior and propagation of cracks of numerical granite samples through the Brazilian split test and to provide a reference for predicting the behavior of real granite samples.

The numerical models of granite containing two fissures are established using the parallel bond model (PBM) and the smooth joint model (SJM) in PFC2D. The peak stresses, number of cracks and anisotropic ratios are obtained to study the influence of the mineral composition and the angle of inclination of rock bridge on the strength, failure mode and deformation characteristics.

The numerical results obtained show that the mineral composition has a marginal influence on the peak stress. When the angle of inclination of rock bridge β increases, the peak stress drops to its minimum value at β = 90° and then gradually increases to a relatively low level. The behavior of cracks falls into three categories based on the distribution of cracks. By analyzing the stress–strain curve and the process of crack propagation for sample No. 4 with β = 60°, it is found that the process of failure can be divided into four stages and tensile cracks dominate. The anisotropic ratios of peak stress and a number of cracks obtained show that the peak stress is low anisotropic and the number of cracks is medium anisotropic.

This paper presents a numerical simulation method to analyze mechanical behavior and propagation of cracks under different conditions. The proposed method and the results obtained are useful for predicting the behavior of real granite samples in laboratory and engineering projects.

The purpose of this paper is to analyze the unbalanced magnetic pull (UMP) of the rotor of traction motor and the influence of the UMP on thermal characteristics of traction motor bearing.

The unbalanced magnetic pull on the rotor with different eccentricity was calculated by Fourier series expansion method. A bearing thermal analysis finite element model considering both the vibration of high-speed train caused by track irregularity and the UMP of traction motor rotor was established. The validity of the model is verified by experimental data obtained from a service high-speed train.

The results show that thermal failure of bearing subassemblies most likely occurs at contact area between the inner ring and rollers. The UMP of rotor of traction motor has a significant effect on the temperature of the inner ring and roller of the bearing. When the eccentricity is 10%, the temperature can even be increased by about 12°C. Therefore, the UMP of rotor of traction motor must be considered in thermal analysis of traction motor bearing.

In the thermal analysis of the bearing of the traction motor of high-speed train, the UMP of the rotor of the traction motor is considered for the first time

This paper aims to clarify the spatial connection characteristics and organization mode of logistics economy of 21 cities in Guangdong Province under the background of the integrated development of Guangdong, Hong Kong and Macao Bay area, and explore the spatial development characteristics and influencing factors of logistics economy in Guangdong Province.

This paper constructs the development level model of urban logistics economy in Guangdong Province from three aspects: demand level, supply level and support level, and uses the entropy weight method to measure the development level index of urban logistics economy in Guangdong Province. Then, the traffic accessibility index model is used to measure the traffic accessibility index between cities in Guangdong Province. Finally, using the social network analysis method, combined with the development level index of urban logistics economy in Guangdong Province and the urban traffic access index in Guangdong Province, this paper analyzes the spatial connection characteristics and influencing factors of logistics economy network in Guangdong Province.

There are regional differences in the development level of logistics economy in Guangdong Province; The overall network density of its logistics economic connection is large, but there is an imbalance in the network structure, and the core edge phenomenon is obvious; Logistics economic space presents the characteristics of double core development.

Because the research object is the spatial connection characteristics of logistics economy in Guangdong Province, the research results may lack universality. Therefore, researchers are encouraged to put forward further tests.

By studying the spatial connection mode of logistics economy in 21 cities in Guangdong Province, China, this paper promotes the original methods and empirical contributions, and constructs the research framework of spatial relationship of logistics economy. This research framework is universal to a certain extent.

This paper is conducive to promoting the integrated development of logistics economy in Guangdong Province and improving the balance of regional development of logistics economy.

Firstly, this study provides a new perspective to understand the spatial relationship and spatial spillover of logistics economy from relational data rather than attribute data. Secondly, This study enriched and broadened the research topic of spatial correlation of logistics economy. Thirdly, this research aims to promote the original methods and empirical contributions. Specifically, this study establishes a comprehensive research framework on the spatial network structure of logistics economy.

This study aims to evaluate the effect of thermal aging temperature on the properties of Cu/Al joints.

A new method in which 1 µm Zn-particles and SAC0307 with a particle size of 25–38 µm were mixed to fill the joint and successfully achieved the micro-joining of Cu/Al under ultrasonic-assisted at 200°C, and then, the effect of aging temperature on the properties of Cu/Al joints at different aging times was researched.

The results showed that the Cu interface intermetallic compounds (IMCs) had the same composition and had two layers with Cu₅Zn₈ near the Cu substrate and CuZn₅ near the solder. As the aging time increased, CuZn₅ gradually transformed to Cu₅Zn₈, and the thickness of the CuZn₅ layer gradually decreased until CuZn₅ disappeared completely. There was a Sn–Zn solid solution at the Al interface, and the composition of the Al interface of the Cu/Al joints did not change with changing temperature. The IMC thickness at the Cu interface of the joints continued to increase, and the shear strength of the Cu/Al joints decreased with increasing aging temperature and time. Compared with the as-received samples, the IMC thickness of the Cu interface of joints increased by 371.8% and the shear strength of the Cu/Al joints was reduced by 83.2% when the joints were aged at 150°C for 24 h. With an increase in aging temperature, the fracture mode of the Cu/Al joints changed from being between solder balls and Zn particles to between Zn particles.

With increasing aging temperature, the shear strengths of the Cu/SACZ/Al joints decreased at the same aging time, the shear strength of Cu/SACZ/Al joints at 150°C for 24h decreased by 83.2% compared with that of the as-received joints.

This study aims to research properties of Cu/SAC0307 mixed solder balls/Cu joints with different Zn-particles content at low-temperature under ultrasonic assisted.

A new method that 1µm Zn particles and Sn-0.3Ag-0.7 (SAC0307) with a particle size of 25–38 µm were mixed to fill the joint and successfully achieved micro-joining of Cu/Cu under ultrasonic-assisted at low temperature.

The results showed that with a continuous increase in the Zn-particle content, the interfacial intermetallic compounds (IMCs) of the upper and lower interfaces of joints gradually changed from scallop-shaped Cu₆Sn₅ to wavy-shaped Cu₅Zn₈. Moreover, the IMC thickness of the upper/lower interface of joints first decreased and then increased with increasing Zn-particle content. The shear strengths of joints increased with Zn-particle content, the shear strength of joints went to a maximum of 29.76 MPa when the Zn-particle content was 40%, an increase of 62.6% compared to joints without Zn particles. However, as the Zn-particle content continued to increase, the shear strengths of the joints decreased. Additionally, when the Zn content increased to 50%, because the oxidation degree of Zn particles increased, the joints were mainly broken among Zn particles.

A new method that 1µm Zn particles and Sn-0.3Ag-0.7 (SAC0307) with a particle size of 25–38 µm were mixed to fill the Cu/Cu joint at 180°C.