Search results

The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system. This paper aims to define and substantiate the assessment of the structural integrity and dynamical integrity of high-speed trains in both theory and practice. The key principles and approaches will be proposed, and their applications to high-speed trains in China will be presented.

First, the structural integrity and dynamical integrity of high-speed trains are defined, and their relationship is introduced. Then, the principles for assessing the structural integrity of structural and dynamical components are presented and practical examples of gearboxes and dampers are provided. Finally, the principles and approaches for assessing the dynamical integrity of high-speed trains are presented and a novel operational assessment method is further presented.

Vehicle system dynamics is the core of the proposed framework that provides the loads and vibrations on train components and the dynamic performance of the entire vehicle system. For assessing the structural integrity of structural components, an open-loop analysis considering both normal and abnormal vehicle conditions is needed. For assessing the structural integrity of dynamical components, a closed-loop analysis involving the influence of wear and degradation on vehicle system dynamics is needed. The analysis of vehicle system dynamics should follow the principles of complete objects, conditions and indices. Numerical, experimental and operational approaches should be combined to achieve effective assessments.

The practical applications demonstrate that assessing the structural integrity and dynamical integrity of high-speed trains can support better control of critical defects, better lifespan management of train components and better maintenance decision-making for high-speed trains.

Firms aiming to enhance firm performance require specific investment and qualification of capability. However, the relationship between these factors and firm performance is influenced by boundary conditions. This study focuses on the role of shared values as a governance mechanism in moderating the relationship between specific investment, qualification of capability, and firm performance.

Drawing on transaction cost analysis, the authors develop a theoretical model to explore how shared values moderate the relationship between specific investment, qualification of capability, and firm performance. The authors collected data from 156 firms in Cote d’Ivoire, resulting in a sample of 216 observations. The authors employed hierarchical regression analysis and the “pick-a-point approach” to examine how specific investment and qualification of capability impact firm performance at different levels of shared values.

The results indicate that specific investment and qualification of capability have a partially positive impact on firm performance. Interestingly, shared values are an important moderating variable, acting as a boundary condition that affects the relationship between specific investment, qualification of capability, and firm performance. Specifically, specific investment leads to excellent firm performance only when shared values are not sufficiently high, whereas qualification of capability leads to superior firm performance only when shared values are sufficiently high.

This study has three research implications. First, this study enriches TCA literature by identifying shared values as a boundary condition and examining the moderating role of shared values. Second, the study findings discover new insights into how specific investment and qualification of capability enhance or inhabit organizational performance at different levels of shared values. Third, this study extends the existing research and reveals the specific conditions for positive or negative relationships between specific investment and organizational performance and qualification of capability and organizational performance.

First, compared to specific investment, qualification of capability has greater effect on organizational performance. Second, when considering whether to increase specific investment or/and improve qualification of capability, executives are encouraged to first evaluate their firm's level of shared values and then make appropriate strategic decision accordingly. Third, six tactics are recommended for enhancing shared values.

This study enriches the literature on transaction cost analysis and contributes to understanding the moderating role of shared values. The findings shed light on the specific investment, qualification of capability, and firm performance relationships. Additionally, this research highlights the importance of considering shared values as a boundary condition in examining these relationships.

Searching for a job is an important process that influences short- and long-term career outcomes as well as well-being and psychological health. As such, job search research has grown tremendously over the last two decades. In this chapter, the authors provide an overview of prior research, discuss important trends in current research, and suggest areas for future research. The authors conceptualize the job search as an unfolding process (i.e., a process through which job seekers navigate through stages to achieve their goal of finding and accepting a job) in which job seekers engage in self-regulation behaviors. The authors contrast research that has taken a between-person, static approach with research that has taken a within-person, dynamic approach and highlight the importance of combining between- and within-person designs in order to have a more holistic understanding of the job search process. Finally, authors provide some recommendations for future research. Much remains to be learned about what influences job search self-regulation, and how job self-regulation influences job search and employment outcomes depending on individual, contextual, and environmental factors.

This study aims to investigate the coupling reaction of epoxide and CO₂ catalysed by alkali metal salts in the presence of ß-cyclodextrin (ß-CD) derivatives to generate cyclic carbonates at various conditions.

The coupling reaction was catalysed by alkali metal salts. The effects of the co-catalysts were investigated by using the conversion rate of raw materials. The affecting factors, such as reaction temperature, amount of the co-catalyst and reaction time, were explored. The possible mechanism of the coupling reaction was discussed.

Results showed that the structure of ß-CD is an important factor influencing the catalytic activity for the coupling reaction of epoxide with CO₂. The catalytic system of 2,3,6-trimethyl-ß-CD with potassium iodide (KI) showed a high catalytic activity. The protocol was expanded to various epoxides, which provided the corresponding cyclic carbonates in excellent yields. The apparent decrease in the yields was not detected after four recycling times. Moreover, the mechanism for the synergetic effect of the catalyst was proposed.

The coupling reactions were achieved in the presence of different structure of ß-CD as co-catalysts. The affecting of substituent of ß-CD were investigated.

Micro-holes are drilled and plated in flexible printed circuit boards (FPCs) for connecting circuits from different layers. More holes, with diameters smaller than 0.3 mm, are required to be drilled in smaller areas with flexible circuits’ miniaturization. The micro-hole quality of micro-drilling is one of the biggest issues of the flexible circuit manufacturers’ production. However, it is not easy to control the quality of micro-holes. The purpose of this study was to conduct research on the tool wear characteristics of FPC drilling process and its influence on micro-hole quality to improve the micro-hole quality of FPC.

The tool-wear characteristics of micro-drills after FPC drilling were observed. The influence of spindle speed, feed rate, number of drilled holes and entry board materials on tool-wear was analyzed. The hole qualities of FPC micro-drilling were measured and observed. The relationship between tool-wear and hole quality was analyzed.

The result showed that the tool-wear characteristics of FPC micro-drilling was similar to the tool-wear characteristics of rigid printed circuit board (RPC) micro-drilling. Abrasive wear occurred on both the main cutting edges and the chisel edges of micro-drills, even though there was no glass fiber reinforcing the cloth inside FPC. Resin adhesion was observed on the chisel edge. The influence of feed and number of drilled holes on tool-wear was significant. Tool-wear significantly influences the hole quality of FPC. Tool-wear will largely decrease the hole position accuracy of FPC micro-holes. Tool-wear will increase the thickness of PI nail heads and the height of exit burrs. Fracture was the main difference between tool wear of FPC and RPC micro-drilling. Resin adhesion of RPC was much more severe than FPC micro-drilling. Increasing the spindle speed properly may improve tool life and hole quality.

The technology and manufacturing of FPC has been little investigated. Research on micro-drilling FPC and research data is lacking so far. The micro-hole quality directly affects the reliability of FPC. Thus, improving the micro-hole quality of FPC is very important.

Although leveraging social media to access healthcare information is nothing new, a boom in short video apps offers new potential for disseminating health-related information. However, it is still unclear how short video apps might facilitate and benefit users’ consumption of health information. Furthermore, the technology features of short video apps complicate attempts to conduct research about them; as a consequence, they have been understudied. For addressing these concerns, this study adopts an affordance perspective to investigate the relationship between affordances and user experience and to examine factors that contribute to users’ intention to continue using short video apps to obtain health information.

Drawing upon affordance theory, we constructed a research model that integrates four types of affordances (livestreaming, searching, meta-voicing and recommending), three types of user experience (immersion, social presence and credibility perception), and user’s intention to continue use. We employed an online survey and obtained a sample of 372 valid responses from TikTok (DouYin) users in China. The partial least squares (PLS) method was used to analyze the data.

The study found that the user experience, in terms of social presence, immersion and credibility perception, can significantly predict users’ intention to continue using short video apps to obtain health information. Furthermore, the user experience was positively associated with the different affordances provided by the short video apps.

The findings of this study have several implications. First, the study contributes to the health information behavior literature by incorporating the aspect of user experience. Moreover, the study extends the application of affordance theory to users’ health information acquisition, and it carries some practical implications on how to leverage the great potential of short video apps to serve public health communication better.

The advanced technology enables retailers to develop customer profile analysis (CPA) to implement personalized pricing. However, considering the efficiency of developing CPA, the benefit to different retailers of implementing more precise personalized pricing remains unclear. Thus, this essay aimed to investigate the impact of efficiency on participants’ strategies and profits in the supply chain.

A two-stage game model was introduced in the presence of a manufacturer who sets his wholesale price and a retailer that decides her CPA strategy. The equilibrium results were generated by backward induction.

Most retailers are willing to develop the highest CPA to implement perfect personalized pricing, but those inefficient retailers with high production costs would like to determine a middle CPA to implement bounded personalized pricing. The retailers’ profits may decrease with the efficiency of developing CPA when the efficiency is middle. In this case, as the efficiency improves, the manufacturer increases the wholesale price, resulting in lower demand and thus lower profits. Moreover, define a Pareto Improvement (PI) strategy as one that benefits both manufacturers and retailers. Therefore, uniform pricing is a PI when the unit cost is high and the efficiency is low; personalized pricing is a PI when the unit cost is low and the efficiency is low or high; otherwise, there is no PI.

This study is the first that investigates how the retailer develops CPA to implement personalized pricing on a comprehensive spectrum, which can provide practical insights for retailers with different efficiencies.

The purpose of this paper is to estimate the impact of China's outward foreign direct investment (OFDI) conducted by exporting firms on their productivity.

This study uses two Chinese firm-level datasets. To reduce the bias when merging the two datasets, this study uses a comprehensive link approach to obtain more observations. The propensity score matching method is employed together with the difference-in-difference and difference-in-difference-in-difference approaches to identify the casual effects.

The study finds that exporting firms become more productive through learning effect via OFDI, and the positive impact of OFDI on total factor productivity materializes very quickly but subject to diminishing return. The study also finds that state-owned enterprises gain less learning effect via OFDI than private-owned enterprises, and firms with higher export intensity or larger size tend to gain less improvement in productivity via OFDI.

This is one of the first studies to investigate empirically the impact of OFDI conducted by exporting firms on their productivity. In particular, the study analyzes three types of firm heterogeneous factors, namely, ownership, export intensity and size, in affecting exporting firms' learning effect via OFDI.

Many waste-to-energy (WTE) plants are constructed and operated using the public-private partnership (PPP) mode in China. However, risk events of PPP WTE incineration projects sometimes occur. This study aims to clarify the relationship of risks in China's PPP WTE incineration projects and identify the key risks accordingly and risk transmission paths.

A risk list of PPP WTE incineration projects was obtained based on literature analysis. Moreover, a hybrid approach combining fuzzy sets, decision-making trial and evaluation laboratory (DEMATEL) and interpretive structural modeling (ISM) was developed to analyze the causality of risks, explore critical risks and reveal the risk transmission paths. The quantitative analysis process was implemented in MATLAB.

The results show that government decision-making risk, government credit risk, government supervision behavior risk, legal and policy risk, revenue and cost risk and management capacity risk are the critical risks of PPP WTE incineration projects in China. These critical risks are at different levels in the risk hierarchy and often trigger other risks.

Currently, there is a lack of exploration on the interaction between the risks of PPP WTE incineration projects. This study fills this gap by examining the key risks and risk transfer pathways of PPP WTE incineration projects from the perspective of risk interactions. The findings can help the public and private sectors to systematically understand the risks in PPP WTE incineration projects, thus enabling them to identify the risks that need to be focused on when making decisions and to optimize risk prevention strategies. The proposed hybrid approach can offer methodological ideas for risk analysis of other types of PPP projects.