The purpose is to bring together all bibliographic references of the published literature on electronic books (e‐books) and related technologies in one source so that it will save…
Abstract
Purpose
The purpose is to bring together all bibliographic references of the published literature on electronic books (e‐books) and related technologies in one source so that it will save time for others in conducting literature searches and reviewing the developments.
Design/methodology/approach
The information included in this bibliography is collected systematically from all the published sources in the world such as journal articles, conference papers, conference proceedings, books, reports and PhD theses on e‐books until the last quarter of 2004. Mainly it covers e‐books, e‐books publishing, the impact of e‐books on different types of users, e‐book publishing techniques and trends, e‐book user interfaces and other technologies related to e‐publications.
Findings
As computer usage continues to grow exponentially, the desire of users to use electronic publications (e‐publications) has also increased tremendously. This has led to the publication of materials in electronic form as e‐publications on both CD‐ROMs and web. The e‐book is one of the several forms of e‐publications and its popularity has been growing steadily for the past decade.
Originality/value
This bibliography will be useful to all researchers conducting research in any areas related to e‐books and e‐book publishing.
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Shujing Li, Xiaojuan Huang, Zhiheng He, Yongxiang Liu, Hui Qu and Jing Wu
The purpose of this paper is to introduce a double-stator switched reluctance machine (DS-SRM) for electric vehicles (EVs) and to propose multi-mode operations for this machine.
Abstract
Purpose
The purpose of this paper is to introduce a double-stator switched reluctance machine (DS-SRM) for electric vehicles (EVs) and to propose multi-mode operations for this machine.
Design/methodology/approach
Analysis of flux linkage distributions and torque characteristics using finite element method (FEM). Building a dynamic simulation model based on electromagnetic characteristics, mathematical equations and mechanical motion equations of the DS-SRM drive system. The paper proposes multi-mode operations (inner-stator excitation mode, outer-stator excitation mode and double-stator excitation mode) based on motor working regions. It also conducts simulation and experimental results to verify the effectiveness of the proposed multi-mode operations strategies and control schemes.
Findings
There is almost no electromagnetic coupling between the inner and outer stators due to the specially designed rotor structure and optimized windings polarity configuration. Analysis of flux linkage distributions and torque characteristics verified the independence of inner and outer stators. Proposal of multi-mode operations and corresponding control rules achieved the smooth switching between different modes.
Originality/value
The paper introduced the DS-SRM for EVs and proposed multi-mode operations, along with control rules, to optimize its performance. The specially designed rotor structure, optimized winding polarity configuration, and the proposed multi-mode operations contribute to the originality of the research.
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K.W.E. Cheng, K.F. Kwok, S.L. Ho and Y.L. Ho
Calculation of the winding losses of high frequency transformer based on one‐dimensional field analysis is normally inapplicable for complex winding configurations. This paper…
Abstract
Calculation of the winding losses of high frequency transformer based on one‐dimensional field analysis is normally inapplicable for complex winding configurations. This paper presents a matrix modeling method which can produce a generalized mechanism to solve the AC winding losses. The transformer is modeled in a matrix connected filament. This is an alternative method to the finite element and is a filament approach. Experimental results and computation results using the proposed method are found to have good agreement.
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Guochao Zheng, Fuli Wang, Baiping Yan and Runting Cheng
The purpose of this study is to suppress the temperature rise of high voltage wall bushing metal plate.
Abstract
Purpose
The purpose of this study is to suppress the temperature rise of high voltage wall bushing metal plate.
Design/methodology/approach
First, the authors built a model of a traditional metal plate and got the magnetic field intensity distribution by FEA tools. Optimized according to the magnetic field intensity distribution, the authors slot the traditional metal plate and embed permanent magnets in the slot. Finally, the authors got the temperature distribution diagrams of the above three cases at different current levels by FEA tools.
Findings
Slotted metal plate is beneficial to suppress magnetic induction intensity, but the improvement of the magnetic induction intensity uniformity is not obvious. The method of embedding a permanent magnet in a slotted metal plate can optimize the magnitude and uniformity of the magnetic induction intensity in the metal plate. The larger the current passing through the metal plate, the better the temperature suppression effect of the slotted metal plate and the slotted metal plate embedded in the permanent magnet.
Originality/value
The effect of structural factors, slotting plate and setting permanent magnets on slots on the temperature of supporting plate is studied. The paper proposes two methods, slotting metal panels and embedding permanent magnet metal panels, to solve the problems of eddy current loss and high calorific value of the panel, which is of great significance to the safety of the grid equipment.
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This paper seeks to consider the design of small, naturally cooled, and high‐frequency (in excess of 10 kHz) inductors. Its purpose is to show that the design of such inductors…
Abstract
Purpose
This paper seeks to consider the design of small, naturally cooled, and high‐frequency (in excess of 10 kHz) inductors. Its purpose is to show that the design of such inductors can be obtained from the solution of a signomial program. In its most general form, the signomial program calls for minimising the total mass (or cost) of the inductor whilst ensuring the satisfaction of the inductance value together with constraints imposed by the copper fill‐factor, the allowed temperature rise, Kirchhoff's mmf law, and the core flux density.
Design/methodology/approach
The signomial program is solved using a sequential geometric programming (SGP) approach specifically tailored to the inductor design problem. In essence, SGP seeks a constrained minimum mass (or cost) solution by optimally setting the inductor geometry parameters, the air‐gap length, and the relevant electrical and magnetic quantities.
Findings
Design results reveal that including the inductor geometry parameters in the set of problem variables leads to significant savings in the inductor mass (or cost).
Practical implications
In cases where there are restrictions on the inductor weight, the optimal solution of the signomial program can be used for manufacturing inductors having cores with non‐standard sizes. In other applications where core dimensions are chosen from the manufacturer's database, the SGP approach can be used to complete the design by either maximising the inductance value or minimising the total loss whilst enforcing a given inductance value.
Originality/value
This work presents a first attempt to optimise an inductor design via signomial programming. The proposed solution methodology is based on SGP, but specifically adapted to the inductor design problem.
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The purpose of this paper is to present a new method of measuring thermal resistance of power light-emitting diodes (LEDs). Properties of power LEDs strongly depend on their…
Abstract
Purpose
The purpose of this paper is to present a new method of measuring thermal resistance of power light-emitting diodes (LEDs). Properties of power LEDs strongly depend on their internal temperature. The value of this temperature depends on the cooling conditions characterized by thermal resistance.
Design/methodology/approach
The new method of measuring the value of this parameter belongs to the group of electric methods. In this method, the problem of estimating the value of electrical power converted into light is solved. By comparing the values of the case temperature obtained for the LED operating in the forward mode and the reverse-breakdown mode, the thermal power is estimated. On the basis of the measured value of the thermally sensitive parameter (the LED forward voltage) and the estimated value of the thermal power, thermal resistance is calculated.
Findings
The elaborated method was used to measure thermal resistance of the selected types of power LEDs operating at different cooling conditions. The correctness of the elaborated measurement method was proved by comparing the results of measurements obtained with the use of the new method and the infrared method.
Research limitations/implications
On the basis of the obtained results of measurements and the catalog data of the tested diodes, the dependence of the measurement error of thermal resistance of the LED on its luminous efficiency is discussed.
Originality/value
The new measurement method is easy to use and more accurate than the classical method of thermal resistance measurement of the diode.
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Sumeet Khalid, Faisal Khan, Basharat Ullah, Zahoor Ahmad and Siddique Akbar
This paper aims to provide an overview of the recent developments and new topologies of single-phase moving magnet linear oscillating actuators (MMLOAs). The key advantage of the…
Abstract
Purpose
This paper aims to provide an overview of the recent developments and new topologies of single-phase moving magnet linear oscillating actuators (MMLOAs). The key advantage of the MMLOA when compared with conventional LOA is the absence of screws, gears and crankshaft mechanism, which results in fewer mechanical parts, simple structure, easy fabrication, lower noise levels and negligible frictional losses.
Design/methodology/approach
The review included papers up to August 2021. The structural designs of alternative topologies are deliberated in detail, and their relative merits and demerits are evaluated. Specific design issues, including pole and tooth number combinations, stroke length, magnet pole ratio and split ratio, are investigated. The imperative phenomena of the resonance, as well as the adjustable stroke, are also discussed in detail.
Findings
The electromagnetic performance in terms of thrust force of selected MMLOA topologies is compared. It is observed that the MMLOA with flux bridge topology has the highest thrust force of 365 N because of the large volume of the permanent magnets (PMs) used, which consequently increased the mass of the mover but based on overall performance analysis, single-phase end ferromagnetic Halbach surface-mounted PM LOA has the highest efficiency around 92%.
Originality/value
This review provides a comparative analysis for different tubular MMLOA topologies based on design construction and their electromagnetic performances.
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Abstract
Purpose
An improved simulation model of switched reluctance motor (SRM) for steady-state operation that considers the core losses in the stator and rotor is established to obtain the steady performance of the high-speed SRM during the design, analysis and control of SRM driving system more accurately.
Design/methodology/approach
The transient core loss model for the material and SRM is presented. Then a new method for calculating the flux density of the motor in real time is introduced, and a steady-state simulation model of the SRM including real-time transient core losses calculation model is established according to the transient flux density. Because the transient core losses calculated by above method are the total core losses of the motor, a core losses distribution method is proposed and the steady-state simulation model of the SRM including the distributed core losses’ effect on the phase winding is established.
Findings
The comparison results show that the proposed model has higher accuracy than the traditional model, excluding core losses, especially at the moments when phase voltage is turn-on and turn-off. The proportion of the core losses to the motor losses increases with the increase in speed. So, the core losses’ effect on the steady-state performance of the high-speed SRM cannot be ignored.
Originality/value
The method to obtain flux density in the real time is presented and the improved steady-state simulation model of SRM that considering transient core losses is proposed.
Details
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Ghassem Faezian, Ahmad Darabi and Nader Sargolzaei
This study aims to design the rotor geometry of switched reluctance motor (SRM) in a completely flexible way. In the proposed method, there is no default geometry for the rotor…
Abstract
Purpose
This study aims to design the rotor geometry of switched reluctance motor (SRM) in a completely flexible way. In the proposed method, there is no default geometry for the rotor. The initial geometry of the rotor can start from a circle or any other shape and depending on the required performance takes the final shape during the optimal design. In this way, the best performance, possible with geometric design, can be achieved.
Design/methodology/approach
The rotor boundary of a 4/2 SRM is defined by a few B-splines. Some control points are located around the rotor and changing their locations causes customized changes in the rotor boundary. Locations of these points are defined as design variables. A 2-D finite element analysis using MATLAB/PDE is applied to the SRM model and sensitivity analysis is used to optimization design by means of minimizing of objective function.
Findings
The proposed method has many more capabilities for matching different objective functions. For the suggested objective function, while the conventional rotor torque profile difference with the desired torque profile reaches 40%, this difference for B-spline rotor is about 17%. Experimental results from a prototype motor have a close agreement with analysis results.
Originality/value
The B-splines have been used to design machines and electromagnetic devices. However, this method is used for the first time in design of the whole rotor of a SRM.
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Patrick Sik‐wah Fong, Qiping Shen and Eddie W.L. Cheng
Aims at developing an analytical framework for benchmarking value management. After a review of the extant literature on value management, identifies several critical success…
Abstract
Aims at developing an analytical framework for benchmarking value management. After a review of the extant literature on value management, identifies several critical success factors and related performance metrics. These critical success factors, such as management commitment, facilitator’s skills, brainstorming, group effectiveness, customer satisfaction, etc., represent the key characteristics of the value management methodology. Such a framework provides a foundation for researchers to undertake further research on benchmarking value management. It also serves as an evaluation platform for value management teams to assess their performance.