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1 – 10 of 25Qingpeng Wang, Baodong Bai, Zhen An and Dezhi Chen
The purpose of this paper is to solve the reactive power adjustment and the overvoltage suppression problems in the extra high voltage (EHV) long distance grid, which often…
Abstract
Purpose
The purpose of this paper is to solve the reactive power adjustment and the overvoltage suppression problems in the extra high voltage (EHV) long distance grid, which often appears transient overvoltage, light load loss and other issues.
Design/methodology/approach
One 800 kV EHV magnetically saturation controllable reactor (MSCR) used self-power supply control system is designed. The structure and the working mechanism of the novel MSCR are analyzed in detail. Then the control and capacity step adjustment characteristics are obtained by experiments. The harmonic characteristic is studied by theoretical analysis and low voltage test.
Findings
To solve the problem of harmonics in the working current of nets windings, the fifth and the seventh filers are equipped between the compensation windings and the control system. The effectiveness of the harmonic suppression method is proved by simulation and experiments.
Originality/value
It proves that the 800 kV EHV MSCR design in this paper can achieve the purpose of the reactive power continuous linear adjustment, and the capacity adjustment is sensitive. After filtering, the harmonics level of the working current meets the standard of the EHV grid.
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Dezhi Chen, William Wei, Daiping Hu and Etayankara Muralidharan
Although there have been many discussions on the status and development of original equipment manufacturers (OEMs), theory on how they survive is minimal. Little is known about…
Abstract
Purpose
Although there have been many discussions on the status and development of original equipment manufacturers (OEMs), theory on how they survive is minimal. Little is known about how OEMs survive and upgrade to other business models, such as original design manufacturers (ODMs) and original brand manufacturers (OBMs), in emerging economies. The purpose of this paper is to extend the theory on the survival path of OEMs from the perspective of emerging countries by examining how OEMs survive cost pressures and upgrade to ODMs or OBMs.
Design/methodology/approach
Using a multi-case study method, this study analyzes the survival path employed by OEMs by examining eight firms in the Chinese toy industry.
Findings
This study shows that OEMs remain weak in the global toy industry chain due to labor costs. While some OEMs move to low-cost regions, others turn to OBM management, after transitioning through an ODM model, by investing in research and development and marketing.
Originality/value
This study explores the survival paths of OEM enterprises, showing that OEMs can first upgrade to ODMs and then to OBMs, or they can directly upgrade to OBMs. Shifting from OEM to ODM is an important step in the transition process, although the contract that OEMs have with their foreign partners does not change significantly.
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Using cointegration and Granger causality tests, examines thecausal relationship between defence spending and economic growth inmainland China over the period 1950‐1991. The…
Abstract
Using cointegration and Granger causality tests, examines the causal relationship between defence spending and economic growth in mainland China over the period 1950‐1991. The results show that defence spending is not cointegrated with the real economic growth rate, implying the lack of any long‐run equilibrium relationship between the two variables. In addition, Granger causality tests indicate causal independence between the two variables.
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Thomas C. Tuttle and Shengcheng Chen
Private philanthropy in China is an emerging element of civil society. This paper seeks to examine the role of productivity improvement in a private charity in the context of the…
Abstract
Purpose
Private philanthropy in China is an emerging element of civil society. This paper seeks to examine the role of productivity improvement in a private charity in the context of the relative roles of charities and private business in building a harmonious society. In addition, the paper aims to examine the philosophy of Capital Spirit proposed by Dr Lu Dezhi, founder of the Huamin Charity Foundation, as the basis for a Chinese model of private philanthropy.
Design/methodology/approach
This case study is based on an interview with Dr Lu Dezhi conducted in Beijing by the first author. The article is descriptive, but it also contains analysis of the approach described by Dr Lu in light of the World Confederation of Productivity Science model of SEE‐Productivity and previous history of efforts to shift management paradigms, e.g. quality management, etc.
Findings
Dr Lu provides a rational, systematic and philosophically grounded approach to creating and operating a private philanthropy in China. This model incorporates many of the key aspects of productivity science, including values‐based strategy, data‐based decision making, analysis and evaluation and continuous improvement. In a larger sense, Dr Lu outlines a philosophy that has the potential to shift the management paradigms of Chinese organizations to more sustainable practices.
Originality/value
The focus on productivity improvement in private philanthropy is a topic that is rarely discussed in the management literature. In addition, the approach taken to philanthropy by Dr Lu Dezhi and his philosophy of Capital Spirit as the basis for a “Chinese model” of philanthropy is unique. Finally, the discussion regarding the appropriate role of private sector businesses in an economy based on its stage of development is a unique contribution to the management literature. Contrasting this Chinese model with Western models provides a useful cultural contrast to examine this key question.
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Weishi Chen, Dong Liu, Lili Zhou, Qiquan Li and Dezhi Wu
The study aims to find potential method to enhance the stability and antioxidant activity of vitamins.
Abstract
Purpose
The study aims to find potential method to enhance the stability and antioxidant activity of vitamins.
Design/methodology/approach
Vitamin E (VE) and β-cyclodextrin (CD) were used to prepare the VE-β-CD inclusion complex via a solution method. The yielded VE-β-CD obtained from optimal experimental conditions was characterized. The mechanism of complex formation and the properties of the complex was investigated by steady-state and time-resolved fluorescence techniques. The antioxidant activity of VE-β-CD was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and compared with pure VE.
Findings
Three experimental factors – reaction temperature (T), molar ratio of VE to β-CD (rm) and inclusion time (t) – were studied for the preparation of VE-β-CD. At experimental conditions of T = 60°C, rm = 1:3 and t = 3 h, a maximum inclusion rate of VE (78.62%) was obtained. The Fourier-transform infrared spectroscopy (FTIR) shows that VE molecule was physically encapsulated by β-CD in the yielded product. Subsequentially, the steady-state fluorescence intensity of VE was found to increase upon encapsulation by β-CD due to the hindrance of fluorescence quenching of VE molecules inside the hydrophobic cavity of β-CD, and an inclusion constant K was determined to equal 3.58 × 103 L/mol from the fluorescence results. The fluorescent observation was confirmed by time-resolved fluorescence experiment as the lifetime of VE increased with an increase in β-CD concentration.
Originality/value
The ability of removing radicals by VE was significantly enhanced after the formation of inclusion complex with β-CD.
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Bin Wang, Wanbin Chen, Shan Gao and Dezhi Wang
This paper aims to prepare a composite film on LY12 aluminum (Al) alloy by immersing in dodecyl phosphate and cerium nitrate solution by self-assembling methods. The effect of…
Abstract
Purpose
This paper aims to prepare a composite film on LY12 aluminum (Al) alloy by immersing in dodecyl phosphate and cerium nitrate solution by self-assembling methods. The effect of dipping sequence in dodecyl phosphate and cerium nitrate solution on the corrosion resistance of the composite film is studied.
Design/methodology/approach
The corrosion resistance of the dodecyl phosphate/cerium composite film is investigated by electrochemical measurement and film composition analysis.
Findings
The dipping sequence in dodecyl phosphate and cerium nitrate solutions has a significant impact on the corrosion resistance of the composite film. It shows best corrosion resistance by first dipping in dodecyl phosphate and then dipping in cerium nitrate solution.
Originality/value
The research shown in this work lays a scientific basis of the film preparation for industrial applications in the future.
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Dezhi Li, Lugang Yu, Guanying Huang, Shenghua Zhou, Haibo Feng and Yanqing Wang
To propose a new investment-income valuation model by real options approach (ROA) for old community renewal (OCR) projects, which could help the government attract private…
Abstract
Purpose
To propose a new investment-income valuation model by real options approach (ROA) for old community renewal (OCR) projects, which could help the government attract private capital's participation.
Design/methodology/approach
The new model is proposed by identifying the types of options private capital has in the OCR project, selecting the option model most suitable for private capital investment decisions, improving the valuation model through the triangular fuzzy numbers to take into account the uncertainty and flexibility, and demonstrating the feasibility of the calculation model through an actual OCR project case.
Findings
The new model can valuate OCR projects more accurately based on considering uncertainty and flexibility, compared with conventional methods that often underestimate the value of OCR projects.
Practical implications
The investment-income of OCR projects shall be re-valuated from the lens of real options, which could help reveal more real benefits beyond the capital growth of OCR projects, enable the government to attract private capital's investment in OCR, and alleviate government fiscal pressure.
Originality/value
The proposed OCR-oriented investment-income valuation model systematically analyzes the applicability of real option value (ROV) to OCR projects, innovatively integrates the ROV and the net present value (NPV) as expanded net present value (ENPV), and accurately evaluate real benefits in comparison with existing models. Furthermore, the newly proposed model holds the potential to be transferred to various social welfare projects as a tool to attract private capital's participation.
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Dezhi Wu, Jingjun (David) Xu and Sue Abdinnour
The paper aims to investigate how a tablet's design features, namely, its navigation design and visual appearance, influence users' enjoyment, concentration and control, when…
Abstract
Purpose
The paper aims to investigate how a tablet's design features, namely, its navigation design and visual appearance, influence users' enjoyment, concentration and control, when using tablets for problem-solving, and thereafter how their core flow experiences impact their perceived performance and efficiency with problem-solving.
Design/methodology/approach
This study uses a field survey approach to engage 87 participants in a decision sciences class to use eTextbooks and a few other associated educational apps including CourseSmart app for e-notes and highlighting, sketchbook app and a calculator app in tablets to resolve class problems at a large US university.
Findings
This study finds that the tablet's interface design features (navigation and visual appearance) make users engrossed in their problem-solving processes with perceived enjoyment, concentration and control. This, in turn, impacts their perceived performance and efficiency. Moreover, visual appearance plays the most significant role in arousing users' affective emotions (i.e. enjoyment), while interface navigation is crucial to engage users' deep concentration (i.e. cognition) and control for problem-solving.
Practical implications
Modern tablets are being used widely in various sectors. More in-depth user flow experience design associated with tablet use for problem-solving contexts should be further advocated in order to provide more engaging and meaningful flow experiences to users.
Originality/value
This study shows that the design of the tablet interface can engage users in problem-solving processes in both affective and cognitive ways. It provides valuable insights on tablet interface design for problem-solving.
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Xiaogen Liu, Shuang Qi, Detian Wan and Dezhi Zheng
This paper aims to analyze the bearing characteristics of the high speed train window glass under aerodynamic load effects.
Abstract
Purpose
This paper aims to analyze the bearing characteristics of the high speed train window glass under aerodynamic load effects.
Design/methodology/approach
In order to obtain the dynamic strain response of passenger compartment window glass during high-speed train crossing the tunnel, taking the passenger compartment window glass of the CRH3 high speed train on Wuhan–Guangzhou High Speed Railway as the research object, this study tests the strain dynamic response and maximum principal stress of the high speed train passing through the tunnel entrance and exit, the tunnel and tunnel groups as well as trains meeting in the tunnel at an average speed of 300 km·h-1.
Findings
The results show that while crossing the tunnel, the passenger compartment window glass of high speed train is subjected to the alternating action of positive and negative air pressures, which shows the typical mechanic characteristics of the alternating fatigue stress of positive-negative transient strain. The maximum principal stress of passenger compartment window glass for high speed train caused by tunnel aerodynamic effects does not exceed 5 MPa, and the maximum value occurs at the corresponding time of crossing the tunnel groups. The high speed train window glass bears medium and low strain rates under the action of tunnel aerodynamic effects, while the maximum strain rate occurs at the meeting moment when the window glass meets the train head approaching from the opposite side in the tunnel. The shear modulus of laminated glass PVB film that makes up high speed train window glass is sensitive to the temperature and action time. The dynamically equivalent thickness and stiffness of the laminated glass and the dynamic bearing capacity of the window glass decrease with the increase of the action time under tunnel aerodynamic pressure. Thus, the influence of the loading action time and fatigue under tunnel aerodynamic effects on the glass strength should be considered in the design for the bearing performance of high speed train window glass.
Originality/value
The research results provide data support for the analysis of mechanical characteristics, damage mechanism, strength design and structural optimization of high speed train glass.
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Dezhi Li, Huan Zhou, Shenghua Zhou, Guanying Huang, Xiaoming Ma, Yongheng Zhao, Wentao Wang and S. Thomas Ng
The study aims to pioneer an innovative approach for the evaluation of government portal websites (GPWs) by introducing an eye-tracking-based method. The research meticulously…
Abstract
Purpose
The study aims to pioneer an innovative approach for the evaluation of government portal websites (GPWs) by introducing an eye-tracking-based method. The research meticulously pinpoints and analyses the distinct usability issues and challenges that users encounter while navigating and interacting with GPWs.
Design/methodology/approach
This study devises an eye-tracking-based GPW usability evaluation approach, which focuses on the major functions (i.e. government information disclosure, government services and interactive responses) of GPWs. An Entropy Weighted Technique for Order Preference by Similarity to an Ideal Solution (EW-TOPSIS) method is employed to process eye-tracking indicator results for deriving GPW usability results.
Findings
The proposed approach is demonstrated to assess the usability of 12 GPWs in pilot smart cities in China, and it is found that most GPWs have lower-than-average usability. GPWs with low usability require more cognitive load that exhibit increased fixation and saccade. The comparisons among the GPW usability results from (1) the eye-tracking experiment, (2) questionnaire surveys and (3) the ready-made performance evaluation report validate the effectiveness of eye-tracking-based GPW usability evaluation.
Originality/value
The work contributes to shifting the GPW usability evaluation approach from a subjective judgment paradigm to an objective paradigm, as well as provides implications for enhancing GPW usability, including improving search function, reducing website complexity and prioritizing user needs.
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