A magnetless axial-flux machine for range-extended electric vehicle

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A new fault-tolerant flux-reversal doubly-salient magnetless motor drives with four-phase topology

Paper no. YD-014184The proposed fault-tolerant flux-reversal doubly-salient (FT-FRDS) magnetless motor drive consists of armature winding for driving and DC-field winding for field excitation. The purpose of this paper is to investigate two remedial strategies for fault-tolerant operations of the proposed motor drive under short-circuit faults. First, short-circuit phase can be disabled and the short-circuit fault can then be regarded as the open-circuit fault. By reconstructing the healthy armature phases, the reduced torque can be remedied and this is known as the fault-tolerant brushless AC (FT-BLAC) operations. Second, short-circuit fault can also be remedied based on the DC-field regulation alone, and this is known as the fault-tolerant DC-field (FT-DC) operation. These two remedial operations are compared and verified by the finite-element-method (FEM). © 2015 IEEE.postprin

Fault signature of a flux-switching DC-field generator

Paper no. EH-12Flux-switching DC-field (FSDC) machine has the merits of low-cost and flux control ability. Furthermore, this type of machine also possesses the advantage of fault-tolerant capability [1]. However, a few studies have been done on the analyses of fault signatures of this type of machine even though it has two sets of windings [2]. © 2015 IEEE.published_or_final_versio

An efficient offshore wind-wave hybrid generation system using direct-drive multitoothed rotating and linear machines

This paper presents an offshore wind-wave hybrid generation (WWHG) system, which can efficiently harness the offshore wind and wave energy. The key is to use the multitoothed doubly-salient permanent-magnet (MDSPM) machines for serving the rotating generator and the linear generator. Different from the traditional wind or wave generation system, this WWHG system integrates the wind generation part and wave generation part together to directly harness the wind and wave energy without gear box. The system configuration and machine design are analyzed and discussed in detail. Also, the finite-element method is performed to verify the validity of the proposed two machine design. The results tell that the system has the high reliability and can be upgraded to the suitable size for offshore hybrid-source energy conversion in practical application. © 2014 IEEE.published_or_final_versio

A review of landslide problems and mitigation measures in Chongqing and Hong Kong: Similarities and differences

The cities of Chongqing and Hong Kong are both located at hilly areas which are highly populated, with buildings and major highways located very close to slopes and earth-retaining structures. Landslides and rockfalls are very common in both cities, and large expenditures are being incurred by both Governments on the investigation, design and implementation of mitigation and preventive measures to reduce the likelihood of the loss of life and economic losses due to landslides. As a result of the collaborative studies and technical exchange programs between the University of Hong Kong and the Chongqing Jianzhu University, a more in-depth understanding of the landslide problem, methodology and mitigation measures in Chongqing and Hong Kong was achieved. The objective of this paper is therefore to: (1) highlight the similarities and differences of the slope safety problems which these cities have been facing and (2) present and compare the key technical approaches these two cities have been undertaken to reduce the risk of landslide and rockfalls, so that both cities could benefit from the experience and lesson learnt. Based on the review of literature and published case records, it is concluded that the city of Chongqing has to deal with natural hazards such as earthquake, river erosion and flooding more than that in Hong Kong, but both cities have been applying practical and latest technology to mitigating the landslide problem. It is recommended that the city of Chongqing should consider establishing a sustainable long-term landslide management plan and that the landslide prevention system being used in Hong Kong could be a good reference starting point. © 2004 Elsevier B.V. All rights reserved.postprin

Design and analysis of a new multitoothed magnetless doubly salient machine

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A comparison between a conventional optical method and image-analysis for measuring the unimpeded eruption rate of the rat mandibular incisor

The impeded/unimpeded eruption rates of the rat incisor have been much studied. The most commonly used optical microscopic method, which has inherent weaknesses, was compared here with an image-analysis method to measure the eruption rate of the mandibular incisor. The study also evaluated the incisal edge as a reference point for the measurement of the unimpeded eruption rate, and the frequency of shortening the mandibular incisor. The image-analysis method was found to be a simple and reliable technique that could replace the optical method. There was no significant difference between the data from the two methods; their κ coefficients were similar at the 0.99 level. It was concluded that shortening the incisor in the measurement of the unimpeded eruption rate should be done at least every 48 h, and that the incisal edge of the shortened incisor can be used as the reference point for that measurement. © 2002 Elsevier Science Ltd. All rights reserved.postprin

Changing School Culture - Using IT to Cope with Individual Learning Differences in Schools

(Email: [email protected]) Dr. Lee Kar Tin is Head of the Department of Information and Applied Technology, Hong Kong Institute of Education and Associate Dean, School of Creative Arts, Sciences and Technology. Prior to her current position she was Director, Multimedia and Online Developments of the Faculty of Education at the University of Melbourne as well as an academic member of Education Faculty where she coordinated the implementation of multimedia and web-based delivery developments of various departments and initiated IT related faculty professional development programs for staff. Throughout her career she has been proactively involved in many IT initiatives and facilitated many seminars and workshops for teachers and principals in schools, for faculty in tertiary institutions and for government bodies. She has been invited as keynote and guest speaker and as consultant for various organizations.This presentation is based on a project which is currently in progress in conjunction with the Curriculum Development Institute (CDI) and two partner schools. It focuses on the use of information technology (IT) resources to explore and establish learning and teaching strategies for coping with individual differences in primary classrooms. The teachers involved have developed a resource base that supports innovative delivery models for implementation in their classrooms. In preparing these resources a careful selection is made of appropriate IT resources and tools that can be used to cater for individual learning differences. These resources are designed to run on an online Integrated Learning Environment (ILE) which provides students with the flexibility of working at their own pace at any time from anywhere. The idea is to assist teachers to make use of this tool in an effective way so that they can easily adapt their teaching strategies for specific contexts in order to enhance classroom learning and achieve a beneficial educational outcome. Through continual refinement, the system will then become truly adaptive and sensitive to individual learning differences. The ILE allows teachers to use a variety of teaching strategies, provides a secure basis from which teachers can plan lessons to meet the needs of all students in the class, and, allows teachers to use a wide range of learning resources to provide students with opportunities to develop initiative and independent learning and enable students to enjoy learning through use of IT and be motivated by it.published_or_final_versionCentre for Information Technology in Education, University of Hong Kon

Oxygen-Vacancy-Induced Orbital Reconstruction of Ti Ions at the Interface of LaAlO3/SrTiO3 Heterostructures: A Resonant Soft-X-Ray Scattering Study

Resonant soft-x-ray scattering measurements have been performed to investigate interface electronic structures of (LaAlO3/SrTiO3) superlattices. Resonant scattering intensities at superlattice reflections show clear evidence of degeneracy lifting in t(2g) states of interface Ti ions. Polarization dependence of intensities indicates the energy of d(xy) states is lower by similar to 1 eV than two other t(2g) states. The energy splitting is insensitive to epitaxial strain. The orbital reconstruction is induced by oxygen vacancies and confined to the interface within two unit cells, indicating charge compensation at the polar interfaces. DOI: 10.1103/PhysRevLett.110.017401X112723Nsciescopu

Comparison of effects of sleeve gastrectomy, duodenal-jejunal bypass and ileal transposition for type II diabetes

Oral Presentations: OS9 - Surgery for Diabetes: no. OS9.02INTRODUCTION: Sleeve gastrectomy (SG), duodenal jejuna bypass (DJB) and ileal transposition (IT) have been reported to be effective for the treatment of T2DM. OBJECTIVES: It is unknown which procedure has a stronger anti-diabetic effect. The purpose of this study was to compare the effectiveness of these novel procedures METHODS: SG, DJB, IT and sham operation of each procedure were performed in 10-12 weeks old Goto-Kakizaki rats, a spontaneous non-obese model of T2DM. The glucose homeostasis effect was evaluated by measuring fasting glucose (FBG) and glycosylated haemoglobin (HbA1c). Gut hormonal profiles and lipid absorption were also examined. Rats were observed for 1 year. RESULTS: All three procedures had significant lower FBG when compared to the respective sham groups. DJB and IT had lower FBG than SG (SG vs DJB, p=0.023; SG vs IT, p=0.009) whereas DJB and IT had a similar FBG level, p=0.678. For HbA1c, all procedures had lower levels than the respective sham groups, p<0.001. The HbA1c of SG rebounded on 8th week whereas HbA1c of DJB and IT remained at low level. SG had a significant higher HbA1c level than DJB and IT, p<0.001 while DJB and IT had a similar level, p=0.685. GLP-1 and PYY were raised in DJB and IT whereas GIP level increased in DJB. All three procedures have different lipid absorption profile. CONCLUSION: SG, DJB and IT all had anti-diabetic effect. DJB and IT had more potent anti-diabetic effect than SG. Each procedure has different effects on metabolic diseases and their clinic application deserve individual consideration.published_or_final_versio