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This paper aims to investigate the thermal characteristics of the clutch hydraulic system under various oil flow conditions. Increasing the oil flow is one of the most important approaches to reduce the clutch temperature. However, the effect of the oil flow on the clutch temperature remains to be explored.

The thermal resistance network model and the lumped parameter method are used to study the thermal characteristics of the clutch hydraulic system. The predicted temperature variations of the clutch and the oil are compared with experimental data.

Results demonstrate that the larger the friction power is, the higher the temperatures of the clutch and the oil are. However, the temperature growth rates of the clutch and oil present different trends: the former decreases gradually and the latter increases constantly. Additionally, increasing the oil flow within a certain range gives rise to the decrease of clutch temperature and the increase of oil temperature; nevertheless, their variation trends are gradually weakening. When the oil flow is large enough, it brings a slight effect on the clutch temperature rise.

This paper extends the knowledge into the oil flow supply of the clutch hydraulic system. The conclusions can provide a theoretical guidance for the oil management of the transmission system. Additionally, the thermal resistance network model is also effective and efficient for other hydraulic equipment to predict the temperature variation.

Given the huge investment and complexity of information technology, it is imperative that boards of directors fully play their important role in promoting firms' IT success. This study aims to investigate the effects of boards of directors' external ties on firms' IT success from the perspective of resource dependence theory.

According to the method of the matched sample comparison group, a total of 576 samples of listed enterprises in three periods were obtained.

Results show that both boards' political ties and boards' business ties have a positive impact on firms' IT success. Environmental uncertainty and the institutional environment play different roles in the relationships between two types of external ties and firms' IT success. Specifically, the results show that the institutional environment can regulate the influence of the political association of directors on firms' IT success negatively. In addition, environmental uncertainty regulates the influence of directors' political association on firms' IT success negatively, as well as the influence of directors' commercial association with firms' IT success.

The external ties were measured by cross-sectional data. And the current study focused on two fundamental types of external ties.

Boards' external ties are studied from both political and business perspectives, and the effects of these two types of external ties on firms' IT success are compared. Additionally, the moderating effects of the institutional environment (macro level) and environmental uncertainty (micro level) in these relationships are investigated.

The purpose of this paper is to solve the problem that the analytic solution model of spatial three-dimensional coordinate measuring system based on dual-position sensitive detector (PSD) is complex and its precision is not high.

A new three-dimensional coordinate measurement algorithm by optimizing back propagation (BP) neural network based on genetic algorithm (GA) is proposed. The mapping relation between three-dimensional coordinates of space points in the world coordinate system and light spot coordinates formed on dual-PSD has been built and applied to the prediction of three-dimensional coordinates of space points.

The average measurement error of three-dimensional coordinates of space points at three-dimensional coordinate measuring system based on dual-PSD based on GA-BP neural network is relatively small. This method does not require considering the lens distortion and the non-linearity of PSD. It has simple structure and high precision and is suitable for three-dimensional coordinate measurement of space points.

A new three-dimensional coordinate measurement algorithm by optimizing BP neural network based on GA is proposed to predict three-dimensional coordinates of space points formed on three-dimensional coordinate measuring system based on dual-PSD.

The purpose of this paper is to examine the following research question in partner selection decisions in business-to-business strategic partnerships/collaborations literature: How do inertia and uncertainty affect partner selection? Explicitly, the paper analyzes how inertia of previous alliance selection routines and uncertainty of entire market movement shape firms’ preferences regarding exploratory partner selection (i.e. selecting new partners who never collaborate with the focal firm).

Grounded on inter-firm partnerships, partner selection and network theory literature, the study empirically tests a fine-grained sample of 511 open-end funds initiated by 61 fund management firms in China. To do so, it runs Tobit regression for main analysis and applies a variety of sensitivity analyses to check the robustness.

Results show that inertia in previous partner selection has a negative effect on exploration. Importantly, these inertial forces impact domestic firms but not international firms. Market uncertainty also affects exploratory partner selection: short-term market uncertainty encourages exploration, whereas long-term uncertainty inhibits it. These effects also depend on firms’ type: long-term market uncertainty has a negative effect on exploration for international firms but not for domestic firms. Both types of firms exhibit a stronger tendency toward exploration when they encounter short-term uncertainty. However, this inclination is stronger in international firms.

Earlier research has examined how inertia affects exploitation but largely overlooked its effect on exploration. A critical examination of firm and environment level factors provides a deeper understanding of why and when firms have inconsistent preferences for specific partner selection strategies. Thus, this study offers a unique perspective for understanding firms’ exploratory partner selection by focusing on two important characteristics of focal firms: one internal (inertia) and one external (market uncertainty) in nature.

The application of massive open online courses (MOOCs) helps integrate sustainable development goals (SDGs) into architectural curricula. The essence of MOOC development is building an education platform that promotes the sharing and continuing of global education resources.

This study establishes a four-dimensional evaluation model based on the four characteristics of MOOCs. The quadrilateral area evaluation method is used to create an evaluation radar chart to comprehensively evaluate satisfaction and demand in the traditional teaching model of architectural technology. This study discusses whether the curriculum is suitable for the development of MOOCs and how to optimize the sustainable pedagogical mode according to its characteristics to meet future teaching needs and realize the sustainable development of education.

Satisfaction evaluation found that current education is not open enough from the students' perspective; therefore, MOOCs enhance students' participation and significantly reduce future learning costs. Through demand evaluation, it was found that both teachers and students believed that the lack of direct and effective communication between them and the difficulty in ensuring the learning effect were problems that must be addressed in MOOCs.

This study focused on the sustainability of MOOCs in curriculum development. It emphasizes the combination of MOOCs' teaching modes and the course itself and provides specific guidance and suggestions for improving the course. It uses an evaluation method for objective analysis and visualization.

Nested within the industrial organization and corporate finance literature, this paper aims to analyze the market for cross-border mergers and acquisitions (M&A) in the world economy, developed economies, developing economies and transition economies. As multinational companies hold a large proportion of cash reserves and expand into diverse geographic markets, the paper aims to examine market patterns of high-valuation cross-border acquisition transactions. Specifically, it proposes a framework explaining the influential factors, motives and effects of high-valuation transactions by discussing some case evidences.

Drawing upon inductive and deductive logic, the paper discusses market trends and market patterns of cross-border M&A transactions by triangulating archival data analyses and accessible M&A literature. Some case examples are derived from news archive and official source sites. Regarding sample period, it considers the past two decades 1994-2013 to show market trends in various institutional settings and the past decade 2004-2013 to present market patterns of 62 high-valuation cross-border deals.

The transaction analysis indicates four cycles in the market trend, namely, growing period (1994-2000); declining, but promising period (2001-2006); financial crisis period (2007-2008); and recovering, but reversing period (2009-2013). A number of acquisitions undertaken by firms from emerging economies around the 2007-2008 global financial crisis have exemplified geographic (product) diversification as a primary motive of firm’s global strategy. In particular, a large proportion of sample high-valuation deals are spotted in developed economies such as the USA and the UK. In case of industry pattern, a good number of high-valuation deals are noticed in banking and finance, telecommunications and oil and gas sector.

Although several scholars have examined cross-border acquisitions in economics, corporate finance, strategy and international business literature, there is hardly any study that analyzes high-profile cross-border M&A deals. An exclusive market analysis of high-valuation international deals is important for several reasons. This paper fills this knowledge gap by showing both market trends and market patterns of cross-border M&A transactions. Importantly, to date, this paper is the first to propose a framework explaining the influential factors, motives and effects of high-valuation M&A transactions.

The current literature lacks discussion on the effects of synergy among multiple factors at different levels on foreign subsidiary performance. The purpose of this paper is to explore the configuration of factors affecting foreign subsidiary performance.

The methodology adopted in this paper is the fuzzy-set qualitative comparative analysis (fsQCA). The data are obtained from 125 foreign subsidiaries of Chinese MNCs through questionnaire surveys and secondary data.

The research results reveal that five configurations of antecedent conditions predict high foreign subsidiary performance, and the other two configurations predict not-high performance.

This paper’s main limitation is its only focus on foreign subsidiaries of Chinese MNCs, which means that the findings should be generalized with precaution. The most valuable implication is to identify the configurations that lead to high and not-high foreign subsidiary performance.

This paper addresses the question of how interdependent factors at the national and corporate level are beneficial to foreign subsidiaries’ performance.

This study makes the following contributions to current theories: It provides (1) new insights for understanding the complex causality between antecedent conditions and foreign subsidiary performance and (2) a practical reference for the multinational operations of foreign subsidiaries.

This paper aims to provide a new drilling entry board for printed circuit board (PCB) process, superior in heat dissipation, lubrication, water solubility and hole location accuracy, achieving an excellent drilling process.

Using a mixture of polyethylene glycol (PEG) and water-soluble adhesives as hydrosoluble, endothermic and lubricant resins and aluminum foils as baseplates, a series of coated and aluminous entry boards (CABs) for PCB drilling was successfully prepared. The surface appearance of the entry boards was observed clearly by scanning electron microscopy (SEM). The endothermic and lubricant effects of the resins applied on the CABs was characterized by differential scanning calorimetry (DSC) and their water solubility was tested in the normal-temperature water (25°C). Moreover, the CABs’ good drilling properties were tested when they were used for PCB drilling.

The SEM analysis showed that the surfaces of the resin layers coated on the CABs whose coating thicknesses were less than 80 μm were smoother and flatter, which could improve hole location accuracy and reduce drill breakage ratio. By virtue of DSC, the endothermic and lubricant effects of the CABs were proven. The fusion of PEG in the resin layers could absorb the heat produced by drilling, restrain the temperature of the drill bit and hole rising and lubricate the drill bit efficiently when a hole was being drilled, which could achieve high-quality holes with good production efficiency. The water-soluble test showed that the prepared CABs had excellent water solubility at normal temperature, enabling the resin left on the hole walls and in the flute of the drill bit to be washed away easily and thereby improving the drilling efficiency and quality. The drilling tests showed that the increase in the thickness of the CABs’ coating could improve the hole location accuracy and alleviate the bit wear. In addition, the suitable coating thickness could ensure the firm adhering of the resin coating the aluminum foil, effectively avoid drill intertwist and prevent the resin debris from blocking the drilled holes on the surface of the entry board, which could hinder chip removal, resulting in poor hole wall quality and drill breakage.

This paper has a remarkably high industrial practicality in the PCB manufacture process.

Flow force is one of the crucial factors affecting the performance of conical throttle valves. The purpose of this paper is to determine the relationship between the flow force and operating parameters of the conical throttle valve.

The flow force of the throttle valve can be obtained by the difference between the axial force and static pressure on the valve spool. In this paper, the internal fluid is divided into two regions and the axial force and static pressure are obtained, respectively. In addition, a two-dimensional axisymmetric simulation model and experimental test are carried out to validate the results of the flow force.

It can be seen that the theoretical, simulation and experimental results exhibit high agreement with each other and the error between them decreases with the increase in the size of the opening. The curves of pressure distribution reveal that the pressure on the spool first decreases then increases when it reaches the minimum pressure at the orifice. Additionally, the minimum pressure decreases with the increase of opening and pressure difference. The results also indicate that the increase in the size of the opening and inlet pressure has a positive effect on the flow force. However, the increase in outlet pressure has a negative effect on the flow force.

In this paper, the flow force calculation model of conical throttle valve is established and the influence of operating parameters on the flow force of conical throttle valve is studied.