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The division of labor of e-commerce transaction system is an important research topic. However, there is a certain disparity between the current mainstream research model and the reality, which leads to a biased result. This paper aims to find the effects of transaction efficiency on the evolution of e-commerce transaction system’s division of labor and the relationships between the results and other parameters.

This paper puts forward a definition of transaction efficiency based on transaction services and establishes a model of middleman’s specialized production decision of transaction services on this basis.

The research results show that the transaction efficiency plays an important role on the change of middlemen’s division of labor level. The degree of economic specialization, price of commodities and transaction services and other associated factors also affect middlemen’s division of labor.

This paper is of great significance for evaluating the development level and forecast the development direction of e-commerce.

The purpose of this paper is to establish a simplified model of the closed hydrostatic guideway for the rapid analysis of static and dynamic characteristics. Further, the influence of compressibility and dynamic frequency are taken into consideration in the new dynamic model.

The new model is based on the second kind of Lagrange equation. In this model, the closed hydrostatic guideway is supported by 12 pads, and each oil pad is equivalent to a nonlinear spring-damper system. The equivalent spring coefficient and damper coefficient of the oil pad are extracted by the three different equivalent methods. Finally, the validation experiments of step load response and dynamic stiffness are conducted on a hydrostatic guideway.

For solving the step response, the linear spring-damper model and the nonlinear spring-damper Model 1 are better than the nonlinear spring-damper Model 2. The accuracy of the three methods are very high for static stiffness calculation. For the calculation of dynamic stiffness, the nonlinear spring-damper Model 2 is better than the nonlinear spring-damper Model 1. The linear spring-damper model has low precision for dynamic stiffness calculation, especially at high frequency. The accuracy of the new model is validated by experiments.

The equivalent method of nonlinear spring-damper system has higher accuracy. Different equivalent methods should be adopted for different load types. The computational speeds of the new dynamic model with the three methods are much better than finite element method (about ten times).

The purpose of this paper is to introduce the structure design process of the cantilever spindle with limited installation space and wishing to increase its critical speed.

In this paper, the finite element method was used to analyze the influence of the supporting stiffness and the structure of the spindle on the critical speed, and then the structure of the spindle was designed; moreover, the experiment was accomplished and the experiment results show that the spindle can work stably.

Through analyzing the influence of the supporting stiffness and the structure of the spindle on the critical speed, the following conclusions could be obtained: the shape of the first-mode is the bend vibration of the cantilever of the spindle; the first-order critical speed of the spindle gradually decreases with the diameter and length of the cantilever increasing; the first-order critical speed of the spindle increases with the depth and diameter of the blind hole increasing; and the experiment was accomplished and the experiment results show that the spindle can work stably.

In this paper, the finite element method was used to design the spindle of the testing machine, and satisfactory results were obtained. It can provide a theoretical reference for the design of a similar spindle.

A question of interest is whether online social networks are effective in promoting behavioral changes and weight loss. The purpose of this paper is to examine the contagion effect of an online buddy network on individuals’ self-monitoring behavior.

This study collects data from an online weight-loss community and constructs an online buddy network. This study compares the effects of the network structure of the buddy network and the actor attributes when predicting self-monitoring performance by employing the auto-logistic actor attribute models.

This study confirms the contagion effect on weigh-in behavior in the online buddy network. The contagion effect is significantly predictive when controlling for actor attribute and other network structure effects.

There is limited evidence that one’s weight-related behavior can be affected by online social contacts. This study contributes to the literature on peer influence on health by examining the contagion effect on weight-related behavior between online buddies. The findings can assist in designing peer-based interventions to harness influence from online social contacts for weight loss.

Although a number of studies have researched food firms’ unethical practices, the mechanisms used to prevent these practices remain underexplored from the perspective of corporate governance. As independent directors (IDs) have been viewed as a mechanism to deter corporate misconducts, the purpose of this paper is to investigate the influences of the ratio of IDs on the board, IDs’ industrial experience and their participation in corporate governance training courses on food firms’ unethical production practices.

This study is based on a sample of 239 firm-year observations in Taiwanese food industries. The Poisson model with fixed effects was used to test the research hypotheses.

The results show that board independence and IDs with food industry expertise were not effective in deterring food firms from unethical production practices. The expected monitoring function of IDs would only realize when they complete a sufficient number of corporate governance training courses. These courses can make IDs aware of their responsibilities and roles in governing firms.

This study is the first to identify the effects of corporate governance practices on food firms’ unethical production practices. The value of this study may provide food firms practical solutions that enable corporate executives to behave ethically.

This research aims to investigate how backstage visibility affects intangibility and perceived risk at the pre-purchase stage and how service credence moderates the effect of backstage visibility on intangibility and perceived risk. It also focuses on the effect of backstage visibility on perceived service quality and value at the post-purchase stage and the moderating role of the service contact level.

This research tests the causal relationships between backstage visibility and customers’ service evaluations through two experimental studies.

Study 1 shows that customers who are exposed to backstage cues perceive less pre-purchase risk in the service than those who are not exposed. Pictures plus text information are more effective than text illustrations alone for risk reduction. This risk reduction effect is stronger for high-credence than for low-credence services and is partially mediated by the perceived intangibility of the service. Study 2 reveals that customers with access to backstage cues perceive higher service quality and higher overall value from service experiences. The value increase is more significant for high-contact than for low-contact services.

Future research could apply different methods to different data sources to provide further insight about backstage visibility.

The findings of this research suggest that allowing customers to view some backstage activities before purchase helps tangibilize the service, achieve more effective communication with customers and create more positive service experiences.

The purpose of this study is to develop a normal contact stiffness (NCS) model among three disks of the assembled rotor system, which systematically considers the friction coefficient, the asperities interaction and the elastoplastic contact regime.

Based on the revised fractal theory, considering the friction effect, the elastoplastic contact regime and the asperities interaction in a simple way, the total NCS among three disks of the rod-fastening rotor bearing system is established. Effects of fractal dimension and roughness, friction coefficient, asperities interaction and material properties on the normal stiffness are investigated by simulations and the relevant comparisons are given for examining the reasonability of the proposed model.

NCS will decrease when asperities interaction and friction are included. As the load increases, the influences of asperities interaction and friction on stiffness become serious. NCS will be enhanced when the elastoplastic regime is considered.

A comprehensive NCS model is developed. It provides a theoretical basis for the modeling of the NCS for multi-interfaces.

The purpose of this paper is to provide an optimization method of robot cladding path, which is helpful to solve the problem of path under-optimization in laser cladding forming (LCF) based on robot.

First, the error influence parameters need setting before the cladding path generation, and the model of seeking appropriate error influence parameters is established based on the particle swarm optimization (PSO). Second, to solve the problem of collapse during the LCF process, the reason for collapse is analyzed and a robot cladding path error optimization method based on the layer path interpolation is proposed. Finally, the simulation and experiments are carried out.

Under the premise of giving the expected error of stereo lithography (STL) model, the optimal range of the chord height and the angle control can be quickly found by using PSO algorithm. Aiming at the collapse problem in the laser cladding process, a robot cladding path optimization method based on the layer path interpolation is proposed. A four-layer path interpolation simulation and the contrast experiments before and after the path optimization are completed; the results show that the robot cladding path optimization method can solve the problem of the collapse in laser cladding.

Robot cladding path optimization is one of the key technologies of LCF, and the quality of the robot cladding path is affected by STL model error and the path optimization method. This paper proposed a robot cladding path optimization method for LCF. This method can be used in other additive manufacturing techniques.

The quality of cladding path is important for LCF; this paper first proposed the optimization method of the robot cladding path for LCF to solve the collapse problem.

The purpose of this paper is to focus on the selection of the optimum porous material modified with poly-dopamine coating for peptides enrichment. The adsorption behaviors for peptides and the antioxidant capacity of peptides fraction purified by the porous materials were investigated.

The optimum porous material with the highest adsorption capacity for peptides was selected for surface modification. The surface modified porous material was characterized by SEM, nitrogen adsorption-desorption isotherm and color change.

The results showed that the porous material was successfully modified with poly-dopamine coating. Adsorption capacity for peptides of the modified porous material was enhanced compared to the original porous material. Antioxidant capacity of peptides fraction enriched by the modified porous material was much higher than that enriched by the original porous material, indicating that the introduction of poly-dopamine coating was inclined to enrich peptides with certain amino acid residues.

The structures of peptides are a bit not clear, which is the subject of future investigation.

This contribution provides a method to design and prepare porous materials with poly-dopamine coating to separate and enrich peptides or peptides fraction with high antioxidant capacity.

It showed that polarity, surface area, pore diameter and interactions were contributed to high adsorption capacity. The peptides fraction purified by the modified porous material showed excellent antioxidant capacity through results of reduction of DPPH radical, because of the enrichment of the peptides with certain amino acids residues which were considered to enhance radical scavenging capacity. This paper provides new insights into designing and preparing porous materials with poly-dopamine coating to enrich peptides fraction with high antioxidant capacity.

This paper aims to investigate how a Chinese firm’s strategic orientation impact its knowledge acquisition from its foreign alliance partners through governance mechanisms used in the Sino-foreign alliance partnership.

This research first proposes an integrated model which links a firm’s strategic orientations (entrepreneurial and market orientations), governance mechanism (contract and trust controls), and its knowledge acquisition together. Then, this research collected data from 198 Chinese firms involved in Sino-foreign alliances to test the conceptual model.

For entrepreneurial-oriented alliance firms, a moderate level of contract and a high level of trust are the most efficient uses of control mechanisms for Chinese firms’ knowledge acquisition. In comparison, for market-oriented alliance firms, both contract and trust control mechanisms should be used at the moderate level to achieve maximum knowledge acquisition from their foreign partners.

By introducing a new antecedent for the choice of control mechanisms in the context of Sino-foreign alliance relationships, this study empirically finds a non-linear relationship between contract control and knowledge acquisition and confirms the significant role of trust in facilitating knowledge acquisition between alliance partners from the perspective of alliance firms in emerging markets.