Tien‐Fu Lu, Daniel C. Handley, Yuen Kuan Yong and Craig Eales
Micromanipulation has enabled numerous technological breakthroughs in recent years, from advances in biotechnology to microcomponent assembly. Micromotion devices commonly use…
Abstract
Micromanipulation has enabled numerous technological breakthroughs in recent years, from advances in biotechnology to microcomponent assembly. Micromotion devices commonly use piezoelectric actuators (PZT) together with compliant mechanisms to provide fine motions with position resolution in the nanometre or even sub‐nanometre range. Many multiple degree of freedom (DOF) micromotion stages have parallel structures due to better stiffness and accuracy than serial structures. This paper presents the development of a three‐DOF compliant micromotion stage with flexure hinges and parallel structure for applications requiring motions in micrometres. The derivation of a simple linear kinematic model of the compliant mechanism is presented and simulation results before and after calibration are compared with results from finite element (FE) modeling and experiments. The position control system, which uses an experimentally determined constant‐Jacobian, and its performance are also presented and discussed.
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This study examines the impact of the trading volume on Initial Public Offering (IPO) initial return in the context of an emerging market from January 2006 to December 2016…
Abstract
This study examines the impact of the trading volume on Initial Public Offering (IPO) initial return in the context of an emerging market from January 2006 to December 2016. Models consist of hierarchical and multiple regressions have been evaluated. Our results show, firstly, IPO provides an average of 21.90% of initial return to investors on the first trading day, 9.08% of return on the second day of trading, and 7.12% of return on the third day of return. Secondly, there is a positive relationship between the oversubscription ratio and initial return and no relationship between trading volume and initial return on the first three trading day. Thirdly, the trading volume does not act as a moderator that worsens the relationship between the oversubscription ratio and initial return. Lastly, this study shows that investors should actively participate in the subsequent trading of an IPO. Higher participation will bring greater liquidity and shareholder wealth in the stock market. To the authors' knowledge, this is the first study on the moderating effect of trading volume on IPO initial return in an emerging market.
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Yong Rong Chan, Sankaranarayanan Seetharaman, Jerry Y.H. Fuh and Heow Pueh Lee
This study aims to assess the feasibility of laser powder bed fusion (LPBF) processing using as-received gas-atomized spherical Neodymium-Iron-Boron (NdFeB) powder (17–68 µm)…
Abstract
Purpose
This study aims to assess the feasibility of laser powder bed fusion (LPBF) processing using as-received gas-atomized spherical Neodymium-Iron-Boron (NdFeB) powder (17–68 µm), compared to literature methods that sieve to a narrow size range (<40 µm).
Design/methodology/approach
The research involves single track and layer printing, process optimization and subsequent heat treatment and magnetic annealing. The experimental approach includes conducting systematic printing trials to assess the impact of various parameters on printed track and layer quality, and refining printing parameters through iterative testing. Heat treatment and magnetic annealing are applied to achieve the desired magnetic properties.
Findings
A minimum linear energy density of 0.10 J/mm is required for continuous track formation, with track width largely unaffected by varying linear energy densities. An optimal hatch spacing of approximately 42% overlap avoids layer defects, with 0.10 mm spacing suitable for layer thicknesses between 30 and 80 µm. A stable processing window for energy density (EA) of 0.6–1.0 J/mm2 was identified, allowing cuboid printing despite some discontinuous tracks, indicating potential fusion issues. Maximizing volumetric energy density (EV) within this range correlates positively with part density, achieving 92% density, coercivity of 490 kA/m and remanence of 496 mT. Post-treatment, density increased to 96%, coercivity to 582 kA/m and remanence to 544 mT.
Originality/value
This study fills a significant gap in LPBF literature for NdFeB by using the original wider size range of spherical powder without sieving, demonstrating improved cost-effectiveness, material efficiency and build efficiency. These findings offer practical recommendations for addressing the challenges related to LPBF processing of NdFeB powder.
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Mingfeng Tang, Xiaogang Chen, Qiaohua Li and Yong Lu
This paper aims to determine whether Chinese university entrepreneurship education matches the needs of undergraduates and whether the entrepreneurial interests and expectations…
Abstract
Purpose
This paper aims to determine whether Chinese university entrepreneurship education matches the needs of undergraduates and whether the entrepreneurial interests and expectations of students who have received university entrepreneurship education differ from those of students who have not. The authors hope that the research findings can provide practical implications and suggestions for improving university entrepreneurship education.
Design/methodology/approach
The authors chose one business university, two technology universities, and one medical university in Sichuan province and sent questionnaires to 350 randomly selected undergraduates. Based on data from 315 valid questionnaires, the authors conducted an empirical analysis.
Findings
The authors found that university entrepreneurship education does not fully satisfy students' needs. The authors also found no significant difference between the entrepreneurial interests and expectations of students who have received entrepreneurship education and those who have not.
Originality/value
The existing studies mainly focus on the supply side of university entrepreneurship education but ignored the demand side. The research is to understand the demand side – namely, students' needs for university entrepreneurship education. Are university students interested in new-business creation?. What are their needs for entrepreneurship education? Does Chinese university entrepreneurship education fit those needs? And finally, do the entrepreneurial interests and expectations of students who have received university entrepreneurship education differ from those of students who have not? Moreover, the study context consisted of one business university, two technology universities, and one medical university in a fast-developing region – Sichuan province. These universities are representative of the main categories of Chinese universities. Finally, the authors employ both qualitative and quantitative research methodologies to conduct the study.
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Yong Lu, Wei Zhang, Yuan‐yang Zhao, Zhi‐zhong Wang and Peng‐cheng Shu
The balanced vane pump is a common transmission component in hydraulic systems. Since the physicochemical properties of water and seawater are different from that of mineral oil…
Abstract
Purpose
The balanced vane pump is a common transmission component in hydraulic systems. Since the physicochemical properties of water and seawater are different from that of mineral oil, some problems can occur, for instance, poor lubrication, more leakage, and more corrosion. The paper aims to demonstrate the technical feasibility for the water hydraulic vane pump.
Design/methodology/approach
The material combinations were selected based on related research in literature. The volumetric efficiency and suction performance were measured in the current experiment. The relations between gap clearances and leakage flow, the contact and the friction forces between a vane tip and a cam contour were simulated based on mathematic models.
Findings
The soft‐hard material combinations in the prototype pump show preferable friction characteristics during tests. The axial clearances are the main channels of leakage flow. Pin type vane pump can reduce the contact force of the vane tip.
Originality/value
This paper outlines some key problems of the water hydraulic vane pump, such as the friction pair material,the structure, and the contact force of the vane tip by means of testing the basic performance of pump and mathematic model.
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Zongming Tang, Ian (Yi) Liu, Yong Lu and Dan Yang
In 2005, China carried out a major reform that allows the previously untradeable shares controlled by large shareholders to become tradable in the secondary market. This reform…
Abstract
Purpose
In 2005, China carried out a major reform that allows the previously untradeable shares controlled by large shareholders to become tradable in the secondary market. This reform and subsequent dramatic change of behavior of controlling shareholders, offer researchers a unique opportunity to study the behavior of controlling shareholders and its implication for corporate governance. Asset injection, by which controlling shareholders sell their high quality assets to the listed companies they controlled, became instantly popular after the reform. The purpose of this paper is to provide strong evidence that such asset injection improves both the Tobin's Q and the composite financial performance score of the injected firm.
Design/methodology/approach
Due to the availability of sample data, this paper focuses on two major types of assets injection: the listed companies purchase the large shareholders' physical assets or equity assets (their shares of other companies) in cash; and the listed companies purchase the large shareholders' physical assets or equity assets through private stock offering, often increasing the share proportion of large shareholders.
Findings
The research findings suggest that this full listing reform aligned the interest of controlling shareholders with the company and that controlling shareholders change their behavior from tunneling to propping.
Originality/value
The contributions of this paper are threefold: First, the paper provides strong evidence of large shareholders' propping behavior. Second, the authors use long‐term corporate financial performance measures to study the impact of asset injection. Third, the authors investigate what types of injections will have a bigger impact on financial performance of the injected firms.
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Zhicheng Song, Xiang Li, Xiaolong Yang, Yao Li, Linkang Wang and Hongtao Wu
This paper aims to improve the kinematic modeling accuracy of a spatial three-degrees-of-freedom compliant micro-motion parallel mechanism by proposing a modified modeling method…
Abstract
Purpose
This paper aims to improve the kinematic modeling accuracy of a spatial three-degrees-of-freedom compliant micro-motion parallel mechanism by proposing a modified modeling method based on the structural matrix method (SMM).
Design/methodology/approach
This paper analyzes the problem that the torsional compliance equation of the circular notched hinge is no longer applicable because it is subject to bilateral restrained torsion. The torsional compliance equation is modified by introducing the relative length coefficient. The input coupling effect, which is often neglected, is considered in kinematic modeling. The symbolic expression of the input coupling matrix is obtained. Theory, simulation and experimentation are presented to show the validity of the proposed kinematic model.
Findings
The results show that the proposed kinematics model can improve the modeling accuracy by comparing the theoretical, finite element method (FEM) and experimental method.
Originality/value
This work provides a feasible scheme for CMPM kinematics modeling. It can be better applied to the optimization design based on the kinematic model in the future.
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Xue Zhang, Yezheng Liu, Xin Li and Jianshan Sun
Leveraging information technology (IT) to improve the treatment and support of patients is a widely studied topic in healthcare. For chronic diseases, such as diabetes, the use of…
Abstract
Purpose
Leveraging information technology (IT) to improve the treatment and support of patients is a widely studied topic in healthcare. For chronic diseases, such as diabetes, the use of information technology is even more important since its effect extends from a clinic environment to patients’ daily life. The purpose of this paper is to investigate the impacts of one widely adopted information technology, the mobile phone, on diabetes treatment, specifically on the complicated process of patients’ health, emotions and compliance.
Design/methodology/approach
We leverage a unique longitudinal dataset on diabetes patients’ health status in rural areas of China to study the problem. We also cross-link the dataset with mobile carrier data to further differentiate mobile phone use to phone calls and network use. To address the endogeneity concerns, we apply PSM and a series of instrument variables.
Findings
We identify clear evidence that mobile phone use can significantly improve patients’ emotions and compliance, where the effect is generally larger on patients in worse health conditions. While mobile phone calls clearly benefit diabetes patients, we do notice that mobile phone network use has a negative moderating effect with patients’ health condition on improving compliance.
Originality/value
This study not only enriches our theoretical understanding of the role of mobile phones in diabetes management, it also shows the economic benefit of promoting patients’ use of mobile phones, which should be considered by medical care providers and medical policymakers.