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This paper uses numerical methods to investigate the collision and skidding of rolling elements in a cageless ball bearing. This paper aims to analyse the effects of the rotational speed and number of rolling elements on the rolling element collision and skidding.

Based on Hertzian theory and tribological theory, the collision contact model of the rolling element was established. Based on the proposed model, the differential equations of motion of the two degrees of freedom rolling element were constructed. The fourth-order Adams algorithm solved the collision contact force between the rolling elements. The sliding velocity between the rolling element and the inner and outer races was calculated.

The collision frequency and slip of rolling elements can be reduced by increasing the rotational speed appropriately and reducing the number of rolling elements by one.

The developed model can reveal the collision and slip characteristics of the rolling elements for cageless bearings. This study can provide theoretical guidance for the design and manufacture of cageless ball bearings.

A pine/co-PES composite (PCPES composite) was proposed as the feedstock for powder bed fusion (laser sintering, LS). This paper aims to provide some necessary experimental data and the theoretical foundation for LS of pine/co-PES, especially for the application of using the laser-sintered pine/co-PES parts as complex structural patterns in investment casting.

The PCPES composites with different pine loadings were mixed mechanically. The composite’s preheating temperature and processing temperature during LS were determined experimentally based on the material’s thermal behavior. The effects of pine powder on the binding mechanism of PCPES composites were discussed through analyzing the microstructure of the laser-sintered parts’. Mechanical properties and dimensional precision of laser-sintered PCPES parts in different pine loadings were tested, and the parts’ mechanical properties were strengthened by wax-infiltration post-processing. The influence extents of process parameters on the mechanical properties of laser-sintered 20 Wt.% pine/co-PES parts were investigated using a 1/2 fractional factorials experiment.

20 Wt.% pine/co-PES is considered to be a promising wood-plastic composite for laser sintering. The relationship between mechanical strength of its laser-sintered parts and process parameters was built up using mathematical formulas. Experimental results show density, tensile strength, flexural strength and surface roughness of laser-sintered 20 Wt.% pine/co-PES parts are improved by 72.7-75.0%, 21.9-111.3%, 26.8-86.2%, 27.0-29.1% after post-process infiltration with a wax. A promising application of the wax-infiltrated laser-sintered parts is for investment casting cores and patterns.

The proper process parameters and forming properties of laser-sintered parts are limited to the results of laser sintering experiments carried on using AFS 360 rapid prototyping device.

This investigation not only provides a new feedstock for laser sintering with the advantages of low cost and fabricability but also uses an advanced technique to produce personalized wood-plastic parts efficiently. Mathematical models between mechanical properties of laser-sintered PCPES parts and LS process parameters will guide the further LS experiments using the 20 Wt.% pine/co-PES composite. Besides, the laser-sintered PCPES parts after wax-infiltration post-processing are promising as complex structural patterns for use in investment casting.

This paper aims to propose a suitable atomizing solidification chitosan (CS) gel liquid extrusion molding technology for the three dimensional (3D) printing method, and experiments verify the feasibility of this method.

This paper mainly uses experimental means, combined with theoretical research. The preparation method, solidification forming method and 3D printing method of CS gel solution were studied. The CS gel printing mechanism and printing error sources are analyzed on the basis of the CS gel ink printing results, printing performance with different ratios of components by constructing a gel print prototype, experiments evaluating the CS gel printing technology and the effects of the process parameters on the scaffold formation.

CS printing ink was prepared; the optimal formula was found; the 3 D printing experiment of CS was completed; the optimal printing parameters were obtained; and the reliability of the forming prototype, printing ink and gel printing process was verified, which allowed for the possibility to apply the 3 D printing technology to the manufacturing of a CS gel structure.

This study can provide theoretical and technical support for the potential application of CS 3 D printed gels in tissue engineering.

A new kind of polymer mixture (co-PA-PES) was prepared in different mass ratios, by mixing polyether sulfone hot-melt adhesive (PES-HmA) and copolyamide B249 (PA-B249). This study aims to investigate its characteristics of laser sintering and get the optimal process parameters.

The effect of mass ratio of co-PA-PES on thermal behavior was analyzed using a simultaneous thermal analyzer, and the density and mechanical properties of sintered parts were tested to evaluate the performance of the polymeric system. Scanning electron microscopy and Fourier transform infrared spectroscopy were performed to characterize the microstructure and binding mechanism of sintered co-PA-PES parts. Specifically, mechanical properties of the mixture with 20 Wt.% PA-B249 were optimized based on a design of experiment methodology, along with the restriction of maximum absorbable laser energy density.

Liquid phase fusion was considered as the main sintering mechanism for co-PA-PES, and mechanical interlocking was the dominant binding mechanism. The effects of mass ratios of this material on the thermal properties, density and mechanical properties were obtained via data results. Additionally, compared to neat PES-HmA, co-20 Wt.% PA-PES showed a 71.7 per cent increase in tensile strength, 24.4 per cent increase in flexural strength and 102.1per cent increase in impact strength.

This paper proposed a new kind of polymer mixture as the feedstock for laser sintering with the advantages of low price and easy processing. The filler of PA-B249 effectively improved the performance of the polymer mixture, including but not limited to mechanical properties.

In this study, the authors examined demand-side credit in rural China with the aims of understanding attribute preferences and the willingness of farmers to pay for credit.

The authors implemented an in-the-field discrete choice experiment (DCE) using a D-optimal block (6 × 9 × 3) design applied to 420 farm households across five Chinese provinces (Shandong, Sichuan, Shaanxi, Jiangsu and Henan) in the summer and fall of 2018. The DCE included six attributes including the interest rate, term of loan, type of loan, type of repayment, type of institution and mobile banking services.

Conditional and mixed logit results indicated a downward sloping credit demand curve with variable elasticity across regions. Provincial willingness-to-pay (WTP) indicators suggested that farmers were willing to pay a premium for long-term ( 0.03–0.687%) and low collateral credit loans ( 0.79–2.93%). Also, four of five provinces indicated a preference for loan amortization rather than lump-sum payment. Interestingly, in comparison to the Agricultural Bank of China (ABC), only farmers in Shandong, Sichuan and Shaanxi indicated a preference for rural credit cooperatives (RCCs)/banks and the Postal Savings Bank of China (PSBC). Another quite surprising result was bank services, in our case, access to mobile banking did not appear to induce WTP for agricultural credit. While conditional and mixed logit regression coefficients were similar (and therefore robust), the authors found that there was substantial heterogeneity across attribute preferences on term of loan, type of loan and amortization. Preferences for type of lender and mobile banking were generally homogenous. This result alone suggested that lenders should consider offering a suite of credit products with different attributes in order to maximize the potential pool of borrowers. While there were some differences across provinces, farmers appeared to be indifferent to lenders, and it did not appear that offering banking services such as mobile banking had any bearing on credit decisions.

This paper presents a first step in using in-the-field choice experiments to better understand rural finance in China. Although the sample size satisfies conventional levels of significance and rank conditions, the authors caution against attributing results to China as a whole. Different provinces have different institutional structures and agricultural growing conditions and economies and these effects may differentially affect WTP for credit. Although by all indications farmers were aware of credit, not all farmers, in fact a minority, actually borrowed from a financial institution. This is not unusual in China, but for these farmers, the DCE was posed as hypothetical. Likewise, the study’s design was based on a generic credit product typical of rural China, and the authors caution against making inferences about other products with different attributes and risk structures.

This study is motivated by the rapidly changing dynamic in China's agricultural economy. With specific reference to new laws and regulations about the transfer of land use rights (LURs), China's agricultural economy is undergoing significant and rapid change which will require better understanding by policy makers, lenders and practitioners of the changing credit needs of farmers, including the new and emerging class of commercial farmers.

To the best of the authors’ knowledge, the authors believe that the result provided in this paper present the first use of in-the-field DCE and are the first to be reported in either the English or Chinese literature on rural credit product design.

The main purpose of present study is to investigate how familial collectivism and gender affect the psychological contract violation–turnover intention relationship by comparing Chinese with American samples.

In total, 688 and 892 full-time workers were recruited, respectively, from China and the USA to form the two samples. Then, three-way interaction regression models were used to test the hypotheses.

The results indicate that familial collectivism will negatively moderate the psychological contract violation–turnover intention relationship in the Chinese sample and positively moderate their relationship in the American sample. Moreover, the moderating effect of familial collectivism on the relationship between psychological contract violation and turnover intention is significant among the male employees and insignificant among the female employees for Chinese sample. Whereas for the American sample, the moderating effects are significant among both the male and the female employees.

This study improves the theoretical model of Turnley and Feldman (1999) by examining the moderating effect of familial collectivism and gender differences on the relationship between psychological contract violation and turnover intention. And two samples (China vs the USA) are used in the study, which helps to explain the possible difference in influencing the relationship between psychological contract violation and turnover intention between two nations. The main practical implication for managers is that organizations should recognize the importance of the gender role and individuals’ culture orientation when implementing different human resource management policies.

The purpose of this paper is to propose and examine an integrated model of spectator satisfaction in mass participant sport events.

The Wuhan marathon, held in the middle of China, was selected serve for the study to examine the antecedents and consequences of spectator satisfaction at mass participant sport events. Data were collected from 956 spectators of the event on the day of the race. Structural equation modeling was used to examine the research model proposed by this study.

Structural equation modeling results indicate the following. First, the event image and perceived social impact of the event are important predictive factors of spectator satisfaction. Second, spectator satisfaction is positively associated with behavioral intentions toward the event and the sponsors' product. Third, spectator satisfaction plays a significant mediating role between the antecedents and consequences; specifically, compared to perceived social impacts of the event, event image has greater indirect effects on both event-related behavioral intentions and event sponsors' products.

Until now, there has not been an integrated research study on the sport spectator satisfaction model in the context of mass participant sport events. This paper thus extends the understanding of the spectator satisfaction in the context of mass participant sport events, and the findings provide valuable implications for holding cities and event organizers of mass participant sport events in emerging countries.

Based on the resource-gain-development framework, this study aims to explore the mediating mechanism of work–family enrichment (WFE) and psychological distress, and the potential positive effect of co-worker support, on employees’ work behaviour.

Data was obtained via a three-stage survey with 400 frontline employees from 13 distinct industries.

This study found that family-supportive leadership (FSL) has a positive impact on employees’ taking charge behaviour (TCB). WFE and psychological distress partially mediated the effect of FSL on TCB and WFE and psychological distress played a serial mediating role between FSL and TCB. Co-worker support positively moderated the relationship between FSL and WFE, TCB and psychological distress.

Managers should consider the problems and difficulties that employees may encounter in completing their work tasks and performance and minimise the interference of non-work factors on employees’ work status. Organisations should also facilitate diversity training for managers to respond to employees’ work and life problems and display family support behaviour.

This study confirmed the role of FSL in WFE, psychological distress and TCB. The results can provide guidance for managers to motivate employees’ TCB.

The purpose of this paper is to discuss the evolution of the food traceability system in China, examine factors that affect consumers' perception of a food traceability system, and determine their willingness to pay for having the system.

Beijing, one of the largest pork markets in urban China, was chosen and 400 consumers were randomly interviewed using questionnaires and finally a logistic model was employed to analyze consumers' willingness to pay for traceable pork.

The authors found that consumers' perception of pork traceability system is subject to a comparatively low level. Purchasing of traceable pork is affected by gender, self‐evaluation of health, awareness of the traceability system, concern about food safety, and the stochastic price willing to pay.

The paper is the first to quantify Chinese consumers' valuation for traceable pork and it helps pork producers and marketers understand consumers' willingness to pay a small premium of 4.5 RMB/kg (0.7 USD) for traceable pork. This finding has imperative policy implications that could help the government deal with the high cost associated with the use of a pork traceability system.

The purpose of this paper is to develop a novel interval Multi-Objective Optimization by a Ratio Analysis plus the Full Multiplicative Form(MULTIMOORA) with combination weights to evaluate the employment quality of college graduates, where the criteria are expressed by interval numbers and the weights of criteria are completely unknown.

Firstly, considering the subjective uncertainty of the weights of the criteria, the interval best worst method (I-BWM) was present to determine the subjective weights of the criteria. Secondly, by the improved interval number distance measure, an improved interval deviation maximization method (I-MDM) was introduced to detemine the objective weights. In the following, based on the I-BWM and the improved I-MDM, a combination weighting method that takes into account the subjective and objective weights is proposed. Finally, a multi-criteria decision-making method based on the interval MULTIMOORA with combination weights is present to evaluate the employment quality of college graduates, and then a comparative analysis with some of the existing distance measures of interval numberswas conducted to illustrate the flexibility.

According to the data of the Report on Employment Quality of Chinese College Graduats released by Mycos Research Institute in 2016–2020 and 2021–2022, the proposed method was used to evaluate the employment quality of college graduates during the period before and after the COVID-19 epidemic. The results verify that the method is more reasonable because the subjective and objective weights of the criteria can be fully considered. Finally, the feasibility and practicability of the proposed method are further verified by varying parameters.

Present an evaluation method on the employment quality of college graduates based on the Interval MULTIMOORA with combination weights considering the subjective and objective weights. And the proposed method is proved that it can provide a more reasonable evaluation results. At the same time, it is verified that the feasibility and the practicability of the proposed method are affected by varying parameters in the paper.