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The purpose of this paper is to study thermal-fluid-solid coupling deformation and friction failure mechanism of bearing friction pairs under the working conditions of high speed and heavy load.

The deformation is simulated based on thermal-fluid-solid coupling method, its deformation distribution law is revealed and the relationships of deformation of friction pairs, rotational speed and bearing weight are obtained.

The results prove that the oil film temperature rises sharply, the lubricating oil viscosity decreases rapidly, the film thickness becomes thinner, the deformation increases, the whole deformation is uneven and the boundary lubrication or dry friction are caused with the increase in rotational speed and bearing load.

The conclusions provide theoretical method for deformation solution and friction failure mechanism of hydrostatic thrust bearing.

The purpose of this paper is to describe a simulation and experimental research concerning the effect of recess depth on the lubrication performance of a hydrostatic thrust bearing by constant rate flow.

The computational fluid dynamics and finite volume method have been used to compute the lubrication characteristics of an annular recess hydrostatic thrust bearing with different recess depths. The performances are oil recess pressure, oil recess temperature and oil film velocity. The recess depth has been optimized. A test rig is established for testing the pressure field of the structure of hydrostatic thrust bearing after recess depth optimization, and experimental results show that experimental data are basically identical with the simulation results, which demonstrates the validity of the proposed numerical simulation method.

The results demonstrate that the oil film temperature decreases and the oil film pressure first increases and then decreases with an increase in the recess depth, but oil film velocity is constant. To sum up comprehensive lubrication performance, the recess depth of 3.5 mm is its optimal value for the annular recess hydrostatic thrust bearing.

The computed results indicate that to get an improved performance from a constant flow hydrostatic thrust bearing, a proper selection of the recess depth is essential.

This paper aims to study the influence of cylindrical texture parameters on the lubrication performance of static and dynamic pressure thrust bearings (hereinafter referred to as thrust bearings) and to optimize their lubrication performance using multiobjective optimization.

The influence of texture parameters on the lubrication performance of thrust bearings was studied based on the modified Reynolds equation. The objective functions are predicted through the BP neural network, and the texture parameters were optimized using the improved multiobjective ant lion algorithm (MOALA).

Compared with smooth surface, the introduction of texture can improve the lubrication properties. Under the optimization of the improved algorithm, when the texture diameter, depth, spacing and number are approximately 0.2 mm, 0.5 mm, 5 mm and 34, respectively, the loading capacity is increased by around 27.7% and the temperature is reduced by around 1.55°C.

This paper studies the effect of texture parameters on the lubrication properties of thrust bearings based on the modified Reynolds equation and performs multiobjective optimization through an improved MOALA.

The purpose of this paper was to obtain the lubrication characteristics of heavy hydrostatic bearing in heavy equipment manufacturing industry through theoretical analysis and numerical simulation.

This paper discusses the influence of oil film thickness variation on velocity field, outlet-L and outlet-R flow velocity under the hydrostatic bearing running in no-load 0 N, load 400 KN, full load 1,500 KN and rotating speeds of 10 r/min, 20 r/min, 30 r/min, 40 r/min, 50 r/min and 60 r/min, by using dynamic mesh technology and FLUENT software.

When the working table rotates clockwise, in the change process of oil film thickness, the fluid flow pattern of the lubricating oil at the edge of the sealing oil is the rule of laminar flow, and the oil cavity has a vortex. The outlet-R flow velocity becomes higher and higher by increasing the bearing load and working table speed, and the flow velocity increases with the decrease in oil film thickness; the outlet-L flow velocity increases with the decrease in oil film thickness under low rotating speed (less than 10 r/min) condition and decreases with the decrease of oil film thickness under high rotating speed (more than 60 r/min) condition.

The influence of the oil film thickness on the flow state distribution of the oil film was analyzed under different working conditions, and the influence rules of oil film thickness on the flow velocity of hydrostatic bearing oil pad was obtained by using dynamic mesh technology.

This paper aims to develop methods for generating disassembly tasks for selective disassembly. The disassembly task contains the disassembly information, namely, disassembly direction, disassembly tool and selective disassembly sequence.

Ontology is adopted to represent the product, and ontology rules are used to represent the disassembly knowledge. A product ontology model (POM) is introduced on the basis of material, connection matrix and interference matrix. Two types of disassembly knowledge are taken into account, one is the disassembly knowledge of disassembly tool selection and the other is the disassembly knowledge of special connections. Based on the POM and the disassembly knowledge, decision support methods are designed to generate disassembly tasks.

A centrifugal pump is used to demonstrate the proposed methods, and the result shows that the methods work well.

The methods developed in this study are fundamental approaches. The ontology and the ontology rules can be extended with more disassembly knowledge.

The main contribution of this research is the development of methods for representing disassembly knowledge based on ontology rules and the decision support methods for generating disassembly tasks.

During the early 1970s, faced with the serious demographic situation, China began to fully implement the policy of family planning in urban and rural regions. Nowadays, the problems of pension and medical care for aged parents confronted by the first generation of the one‐child family have begun to gradually appear. Meanwhile, China's population and the family planning are also faced with some problems that are difficult to solve, including unbalanced fertility rate of urban and rural population, the gender imbalance, the difficulty of the risk diversification in a one‐child family, as well as the profound contradiction between the stability of the family planning policy and the drive of administrative measures. Therefore, it is necessary to establish the integrated‐scheduled life security system of the one‐child family in urban and rural areas, in order to overcome the problems and to promote the transformation of the family planning policy. The purpose of this paper is to discuss the life security system for China's one‐child families.

The life security system for the one‐child family proposed by this paper consists of three issues: the basic security based on the level of social security, the additional security of the policy insurance and the supplementary security of the commercial insurance. The paper begins with the history of the family planning policy in the first section and then go through some relevant articles regarding complementary measures such as maternity insurance, rural endowment insurance that only focused on one aspect of issues associated with the family planning. In section three, four typical problems are listed for the purpose of following discussion of corresponding solutions which are full of deficiency in section four. In part five, the integrated planning of the life security system for Chinese one‐child family is elaborated with risk and fund management. In the last part, we conclude that the family planning policy maintains stable, whereas measures to be taken are adjusted along with changeable new problems.

The policy insurance plays an increasingly important role in dealing with the life security of older people in one‐child families. It may be better to promote the kind of insurance.

The paper comprehensively discusses the life security system for Chinese families in compliance with the family planning policy.

Restaurant entrepreneurs are increasingly leveraging crowdfunding as an alternative financing mechanism. In the context of restaurant crowdfunding, studies have identified factors related to campaign communication that affect crowdfunding success from the entrepreneurs’ perspective. Integrating a funder perspective, this study aims to investigate the role of the consumption value offered by rewards and builds a value-based understanding of restaurant crowdfunding.

This study uses a sample of 3,134 restaurant campaigns launched on the Kickstarter crowdfunding platform, and texts of 34,128 rewards were analyzed using a Python program. A hierarchical linear regression approach with a generalized logistic regression model was adopted to test hypothesized relationships.

Drawing upon consumption value theory (CVT), this study finds that in restaurant crowdfunding, utilitarian value holds a strong inverted-U relationship and participatory value holds a strong linear relationship with crowdfunding success. However, socioemotional value does not have a significant effect on outcomes. This study also finds evidence for positive effects of greater variety, higher number of rewards and lower average pledge level on restaurant crowdfunding success.

This study extends the literature on restaurant crowdfunding by integrating insights on the effects of value offered through rewards. Primarily, this study finds evidence for distinct effects of consumption values for restaurant crowdfunding audience. Practically, this study holds implications for reward menu design and value offering design for restaurant entrepreneurs seeking crowdfunding.

Restaurant crowdfunding has been studied to a limited extent, with extant literature focusing on characteristics of campaign descriptions. The role of rewards is uncovered using CVT and thus a value-based understanding of restaurant crowdfunding is presented.

The purpose of this paper is to investigate the influence of religious entrepreneurs on bank loans and further examine the moderating effect of entrepreneurial gender.

In 2010, the Chinese national survey reported the different religious beliefs of private entrepreneurs. Using this set of survey data, the authors obtain a sample of 4,330 Chinese family firms and employ the Tobit regression approach to examine the relationship between the amount of bank loans and the religious background of entrepreneurs. In addition, the authors use the propensity score matching approach to address the endogeneity issue.

Based on the data from the 2010 national survey, the authors document that the amount of bank loans is significantly higher for Chinese family firms with religious entrepreneurs than for their counterparts. This finding suggests that religious individuals are inclined to be more ethical and honest and Chinese family firms with religious entrepreneurs transfer soft information to banks, and eventually lenders favor religious entrepreneurs with more bank loans. Moreover, the authors reveal that the amount of bank loans is significantly larger for firms with female entrepreneurs than for those without female entrepreneurs. In addition, entrepreneurial gender attenuates the positive relationship between religious entrepreneurs and bank loans.

This study is one of few studies to examine the influence of an entrepreneur’s religious belief on bank credit decisions and adds to previous studies about religious influence on corporate behavior by revealing a positive association between religious entrepreneurs and bank loans. Moreover, this study validates that female entrepreneurs exert positive effects on the amount of bank loans and attenuate the positive influence of religious entrepreneurs on bank loans.

Despite the critical contribution of serial backers in advancing crowdfunding volumes, few studies have addressed the phenomenon of serial backing. Research on the motivations of backers suggests that cognitive antecedents influence pledging in crowdfunding projects according to the theory of planned behavior. However, intrinsic factors associated with different dimensions of well-being may also explain crowdfunding support. This study seeks to advance the understanding of drivers of serial backing by combining the theory of planned behavior and the theory of well-being.

The study draws on survey data from 336 serial backers, complemented by objective data on the number of campaigns and amounts invested by backers from Headstart, the largest crowdfunding platform in Israel. The research model is tested using structural equation modeling.

The findings indicate that the well-being of serial backers mediates the impact of attitude, subjective norms and social norms on their loyalty. However, while loyalty can be explained by elements of both theories, it does not translate into actual serial backing behavior.

This study is the first to systematically explore serial backers' motivations in crowdfunding and the influence of these motivations on their actual behavior. It combines two previously separate theories, the theory of planned behavior and the theory of well-being.

This paper aims to study the impact of CEOs’ personality and social connections on corporate risk-taking in the Russian market.

Using a sample of 93 large listed Russian corporations between 2008 and 2016, this study tests a range of personal traits, including the classical personal characteristics like age and tenure, some country-specific traits such as connections and military experience, as well as other human and social capital characteristics.

This study finds non-linear relationships between corporate risk-taking and CEO age and tenure. This study also finds that firms run by CEOs with military experience take more corporate risk. On the CEOs’ social capital side, this study’s results suggest that both political and educational connections are positively related to corporate risk-taking.

This study also tests some traits that have usually been ignored by the literature, such as marital and family status.