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To understand the service performance of full ceramic ball bearings under extreme working conditions and improve their service life, dynamic characteristic tests of full ceramic ball bearings under ultra-low temperature conditions were carried out by a low-temperature bearing life testing machine, and temperature rise and friction were measured under extreme low-temperature environment.

The heat-flow coupling model of bearing was established by CFD software, and the test results were further analyzed.

The results show that the temperature rise of the bearing is not obvious in the liquid nitrogen environment. With the increase of the chamber temperature, the lubrication state of the bearing changes, resulting in the temperature rise of the outer ring of the bearing. As the temperature of the test chamber increases, the friction force on the bearing increases first and then decreases under the action of multifactor coupling.

The research results provide test data and theoretical basis for the application of all-ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

Network embeddedness has been widely considered in enterprise innovation as an effective means of overcoming resource dilemmas. However, while focussing on acquiring external innovation resources, the existing research often ignores the vital role of internal routine updates. Therefore, this study explores the mechanism by which network embeddedness affects innovation performance of enterprises from the perspective of organisational routine updating.

This paper proposes a theoretical model based on social network theory and organisational routines–immune response theory. A total of 328 pieces of research data on high-tech enterprises in China were collected, and the hypotheses were verified using hierarchical regression analysis.

The results show that the two forms of network embeddedness – structural embeddedness and relational embeddedness, have a positive effect on enterprise innovation performance and a significant positive effect on organisational routine revision and organisational routine creation. Both organisational routine revision and organisational routine creation positively affect enterprise innovation performance and partially mediate the relationship between network embeddedness and enterprise innovation performance.

This conclusion provides a new perspective on the impact of network embeddedness on enterprise innovation performance and expands the related research on organisational routine updating. This study provides a theoretical reference for high-tech enterprises to improve their competitiveness and innovation performance through network embeddedness and organisational routine updating.

For flow around elongated bluff bodies, flow separations would occur over both leading and trailing edges. Interactions between these two separations can be established through acoustic perturbation. In this paper, the flow and the acoustic fields of a D-shaped bluff body (length-to-height ratio L/H = 3.64) are investigated at height-based Reynolds number Re = 23,000 by experimental and numerical methods. The purpose of this paper is to study the acoustic feedback in the interaction of these two separated flows.

The flow field is measured by particle image velocimetry, hotwire velocimetry and surface oil flow visualization. The acoustic field is modeled in two dimensions by direct aeroacoustic simulation, which solves the compressible Navier–Stokes equations. The simulation is validated against the experimental results.

Separations occur at both the leading and the trailing edges. The leading-edge separation point and the reattaching flow oscillate in accordance with the trailing-edge vortex shedding. Significant pressure waves are generated at the trailing edge by the vortex shedding rather than the leading-edge vortices. Pressure-based cross-correlation analysis is conducted to clarify the effect of the pressure waves on the leading-edge flow structures.

The understanding of interactions of separated flows over elongated bluff bodies helps to predict aerodynamic drag, structural vibration and noise in engineering applications, such as the aerodynamics of buildings, bridges and road vehicles.

This paper clarifies the influence of acoustic perturbations in the interaction of separated flows over a D-shaped bluff body. The contribution of the leading- and the trailing-edge vortex in generating acoustic perturbations is investigated as well.

Starting from corporate entrepreneurship, spin-off entrepreneurship and business model theory, this paper aims to examine the key influential factors and inherent mechanism in the process of business model transfer from parent enterprise to spin-off start-ups.

Grounded theory method is fit for constructing theoretical models, which can discover and interpret phenomenon and activities. According to the guidance of theoretical sampling and other core principles in grounded theory, this study extracts two parent enterprises named Haier and Phnix and lots of spin-offs derived from them.

This paper presents the theoretical framework that business models transfer from parents to spin-offs and probes into the embedding logic and connection relationship between factors and categories in this process, such as preconditions, incubation veins, business model elements, stripping mechanism and independent operations.

Although this study is focused on the manufacturing industry, the main characteristics, comparative advantages, governance rules summarized from transfer activities of business model in spin-off entrepreneurship can also bring inspirations to both parent enterprises and spin-off start-ups.

Excavates process and mechanism of business model transfer from internal to external, extends the theoretical perspectives about existing related theories such as corporate entrepreneurship, spin-off entrepreneurship and business model theory and reveals new approaches and methods on business model design, which is different from the past way.

The purpose of this paper is to study police powers and accountability from a comparative perspective in both China and Hong Kong.

This paper compares and contrasts police powers and accountability.

The implications are many, including different political systems in which China is more authoritarian or paternalistic whereas Hong Kong is more pluralistic; checks and balances mechanisms in Hong Kong are far greater than in China; and the concept of accountability to the public is different in that Hong Kong police are accountable to members of the public but the mainland Chinese police force has a limited and top-down concept of accountability.

An original comparative approach to policing in Hong Kong and China.

Pursuit of meaning is at the heart of much of organizational life. It has implications for how different organizational stakeholders associate value to various organizational initiatives. Research on meaning has generally shown that effort increases meaning and favorable valuation of and willingness to pay for economic activities by organizational stakeholders. The authors build on and advance this research by offering theory and experimental evidence showing that effort, particularly at high levels, results in enhanced meaning and favorable valuation when effort does not threaten the focal stakeholders' resources through expectation disconfirmation.

Three experimental studies are designed and conducted in this research. In one study, the authors replicate prior research findings that establish labor generally increases meaning and favorable valuation. In the two subsequent studies, the authors test the proposed hypothesis in this research and check for robustness of the empirical analysis.

The authors find that any internalized threat to the focal stakeholder's resources coupled with a high exertion of effort decreases, rather than increases, meaning and favorable valuation of and willingness to pay for economic activities.

The theory and empirical evidence in this research advance the understanding of how organizational stakeholders may associate effort-induced meaning with various economic activities in counter-intuitive ways. The findings also highlight the importance of recognizing and shaping the expectations of organizational stakeholders in influencing willingness to pay in organizational settings.

The purpose of this study is to develop a piezoresistive absolute micro-pressure sensor for altimetry. For this application, both high sensitivity and high overload resistance are required. To develop a piezoresistive absolute micro-pressure sensor for altimetry, both high sensitivity and high-overload resistance are required. The structure design and optimization are critical for achieving the purpose. Besides, the study of dynamic performances is important for providing a solution to improve the accuracy under vibration environments.

An improved structure is studied through incorporating sensitive beams into the twin-island-diaphragm structure. Equations about surface stress and deflection of the sensor are established by multivariate fittings based on the ANSYS simulation results. Structure dimensions are determined by MATLAB optimization. The silicon bulk micromachining technology is utilized to fabricate the sensor prototype. The performances under both static and dynamic conditions are tested.

Compared with flat diaphragm and twin-island-diaphragm structures, the sensor features a relatively high sensitivity with the capacity of suffering atmosphere due to the introduction of sensitive beams and the optimization method used.

An improved sensor prototype is raised and optimized for achieving the high sensitivity and the capacity of suffering atmosphere simultaneously. A general optimization method is proposed based on the multivariate fitting results. To simplify the calculation, a method to linearize the nonlinear fitting and optimization problems is presented. Moreover, a differential readout scheme attempting to decrease the dynamic interference is designed.

The purpose of this paper is to examine the business-government nexus in Hong Kong as a special case, thereby contributing to a comparative examination of various significant variables affecting the study of political and economic developments in East Asia.

The paper considers the privileged position afforded to the major business groups in Hong Kong’s political system as part of the pro-Beijing United Front. It adopts a historical perspective, relying on existing literature including media reports. As the author is both an academic and a long-term pro-democracy activist, his actual experiences and extensive interviews with various important participants in Hong Kong’s business and political communities offer valuable perspectives.

In the past, the business-government nexus was perceived to be a positive factor that contributed to the territory’s economic growth. In the past decade or so, though, increasing dissatisfaction with the Hong Kong government’s performance and the widening gap between the rich and the poor have led to the emergence of a legitimacy deficit on the part of the government, resulting in rising demands for democracy which have not been met. Divisions on these issues within the local business community have posed a severe challenge to the continuation of the business-government nexus.

The author’s actual experiences and his interviews with other participants in Hong Kong’s politics provide observations of significant value. The Occupy Central campaign, which took off in the territory in 2014, demands serious consideration in terms of its political development and a key element for consideration is the response of the business-government nexus to it.

This paper aims to introduce the history and major achievement of the Chinese private enterprise survey (CPES), which is one of the most enduring large-scale nationwide sample surveys in China, providing important micro firm-level data for understanding and studying the development of Chinese enterprises and entrepreneurs over the past 26 years.

The main body of this paper is based on a bibliometric analysis of all literature using CPES until 2017.

This paper discusses problems that users may encounter during data mining. By doing so, it can assist other researchers to get a better understanding of what has been done (e.g. journals, topics, scholars and institutions) and do their research in a more targeted way.

As members of the survey project team, the authors also take a prospect of the future data design and use, as well as offer some suggestions about how to use the CPES data to improve high-quality development and business environment evaluation in China.

This paper is the first to provide an overall picture of academic papers in China and abroad that have used the CPES data.