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On a non-abelian invariant on complex surfaces of general type Dedicated to Professor Sheng GONG on the occasion of his 75th birthday

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Science China Mathematics 2006年第12期49卷 1897-1900页

作者： CHEUNG Wing-Sum WONG bun Department of Mathematics University of Hong Kong Department of Mathematics University of California at Riverside

In this paper,we give certain homotopy and diffeomorphism versions as a generalization to an earlier result due to ***,bun Wong and Stephen *** concerning a local rigidity problem of the tangent bundle over compact su... 详细信息

关键词： Chern numbers complex surfaces of general type coholomogy group local moduli local deformation space Miyaoka-Yau inequality Yau's global rigidity theorem Yau's uniformization theorem.

Optimal Low-voltage Distribution Topology with Integration of PV and Storage for Rural Electrification in Developing Countries:A Case Study of Cambodia

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Journal of Modern Power Systems and Clean Energy 2020年第3期8卷 531-539页

作者： Vannak Vai Marie-Cecile Alvarez-Herault Bertrand Raison Long bun Department of Electrical and Energy Engineering(GEE) Institute of Technology of Cambodia(ITC)Phnom Penh 12150Cambodia Institute of Engineering UniversitéGrenoble Alpes38000 GrenobleFrance

This paper addresses an optimal design of low-voltage(LV)distribution network for rural electrification considering photovoltaic(PV)and battery energy storage(BES).It aims at searching for an optimal topology of an LV distribution system as well as the siting and sizing of PV and storage over a time horizon of 30 ***,the shortest-path algorithm(SPA)and first-fit bin-packing algorithm(FFBPA)are used to search for the optimal radial topology that minimizes the total length of the distribution line and improves the load ***,the optimal siting of decentralized BES(DeBES)is determined using a genetic algorithm(GA)to eliminate the undervoltage constraints due to the load *** iterative techniques are elaborated to size the maximum peak power of PV and the minimum number of DeBES that can be connected to an LV network without violating the voltage and current ***,the sizing strategy of centralized BES(CeBES)is developed to avoid reverse power flows into the medium-voltage(MV)***,a Monte Carlo approach is used to study the impact of load profile uncertainties on the topology.A non-electrified village in Cambodia has been chosen as a case study.

关键词： Battery energy storage(BES) low-voltage(LV)distribution network Monte Carlo photovoltaic(PV) electrification planning

Remarks on two theorems of Qi-Keng Lu

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Science China Mathematics 2008年第4期51卷 773-776页

作者： CHEUNG Wing-Sum WONG bun Department of Mathematics University of Hong Kong Department of Mathematics University of California

Two alternate arguments in the framework of intrinsic metrics and measures respectively of part of the proof of a famous theorem due to Qi-Keng Lu on Bergman metric with constant negative holomorphic sectional curvature are presented.A relationship between the Lu constant and the holo- morphic sectional curvature of the Bergman metric is *** recent progress of the Yau’s porblem on the characterization of domain of holomorphy on which the Bergman metric is K(?)hler-Einstein is described.

关键词： Bergman metric holomorphic sectional curvature intrinsic metrics and measures Qi-Keng Lu theorem 32F45 32Q05 32W20

7,8-dihydroxyflavone,a small molecular TrkB agonist,is useful for treating various BDNF-implicated human disorders

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Translational Neurodegeneration 2016年第1期5卷 9-17页

作者： Chaoyang Liu Chi bun Chan Keqiang Ye School of Information and Safety Engineering Zhongnan University of Economics and LawWuhan 430073P.R.China Department of Physiology University of Oklahoma Health Sciences Center940 Stanton L.Young Blvd.Oklahoma CityOK 73104USA Department of Pathology and Laboratory Medicine Emory University School of Medicine615 Michael StreetAtlantaGA 30322USA

Brain-derived neurotrophic factor(BDNF)regulates a variety of biological processes predominantly via binding to the transmembrane receptor tyrosine kinase *** is a potential therapeutic target in numerous neurological,mental and metabolic ***,the lack of efficient means to deliver BDNF into the body imposes an insurmountable hurdle to its clinical *** address this challenge,we initiated a cell-based drug screening to search for small molecules that act as the TrkB agonist.7,8-Dihydroxyflavone(7,8-DHF)is our first reported small molecular TrkB agonist,which has now been extensively validated in various biochemical and cellular *** binding to the extracellular domain of TrkB,7,8-DHF triggers TrkB dimerization to induce the downstream ***,7,8-DHF is orally bioactive that can penetrate the brain blood barrier(BBB)to exert its neurotrophic activities in the central nervous *** reports suggest 7,8-DHF processes promising therapeutic efficacy in various animal disease models that are related to deficient BDNF *** this review,we summarize our current knowledge on the binding activity and specificity,structure-activity relationship,pharmacokinetic and metabolism,and the pre-clinical efficacy of 7,8-DHF against some human diseases.

关键词： Flavonoids Neurotrophin BDNF Mimetic compound Receptor agonistic activity

Fabrication of Microlens Array and Its Application:A Review

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 10-18页

作者： Wei Yuan Li-Hua Li Wing-bun Lee Chang-Yuen Chan State Key Laboratory of Ultra-precision Machining Technology Partner Laboratory in the Hong Kong Polytechnic University Shenzhen Branch of State Key Laboratory of Ultra-precision Machining Technology PolyU Shenzhen Research Institute

Microlens arrays are the key component in the next generation of 3D imaging system, for it exhibits some good optical properties such as extremely large field of view angles, low aberration and distortion, high temporal resolution and infinite depth of field. Although many fabrication methods or processes are proposed for manufacturing such precision component, however, those methods still need to be improved. In this review, those fabrication methods are categorized into direct and indirect method and compared in detail. Two main challenges in manufacturing microlens array are identified: how to obtain a microlens array with good uniformity in a large area and how to produce the microlens array on a curved surface? In order to effectively achieve control of the geometry of a microlens,indirect methods involving the use of 3D molds and replication technologies are suggested. Further development of ultraprecision machining technology is needed to reduce the surface fluctuation by considering the dynamics of machine tool in tool path planning. Finally, the challenges and opportunities of manufacturing microlens array in industry and academic research are discussed and several principle conclusions are drawn.

关键词： Microlens array Ultraprecision machining 3D image system MEMS

A planetary companion orbiting the intermediate-mass G Giant HD 173416

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Chinese Journal of Astronomy and Astrophysics 2009年第1期9卷 1-4页

作者： Yu-Juan Liu bun＇ei Sato Gang Zhao Hiroyasu Ando National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Tokyo Institute of Technology 2-12-10okayama Meguro-ku Tokyo 152-8550 Japan National Astronomical Observatory of Japan National Institutes of Natural Sciences 2-21-1 Osawa Mitaka Tokyo 181-8588 Japan Deparfment of Astronomy Graduate University for Advanced Studies Shonan Village Hayama Kanagawa 240-0193 Japan

The discovery of a planetary companion to the intermediate-mass late-type giant star HD173416 from precise Doppler surveys of G and K giants at Xinglong station and Okayama Astrophysical Observatory （OAO） is presented in this letter. The planet has a minimum mass of 2.7 MJ, an eccentricity of 0.21, a semimajor axis of 1.16 AU and an orbital period of 324 days.

关键词： planetary systems -- stars individual HD173416 - stars PlanetarySystems -- techniques: radial velocities

A Dynamic Forecasting System with Applications in Production Logistics

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厦门大学学报（自然科学版） 2002年第S1期41卷 133-134页

作者： CHEUNG Chi-fai LEE Wing-bun LO Victor Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hung HomDepartment of Industrial and Systems EngineeringThe Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong ChinaKowloonHong Kong China Kaz (Fast East) Ltd Room 1705-07Kodak House II39 Healthy Street EastNorth Point Hong Kong China

Production logistics involve the co-ordination of ac tivities such as production and materials control (PMC), inventory management, p roduct life cycle management, etc. Those activities demand for an accurate forec asting model. However, the conventional methods of making sell and buy decision based on human forecast or conventional moving average and exponential smoothing methods is no longer be sufficient to meet the future need. Furthermore, the un derlying statistics of the market information change from time to time due to a number of reasons such as change of global economic environment, government poli cies and business risks. This demands for highly adaptive forecasting model which is robust enough to response and adapt well to the fast changes in the dat a characteristics, in other words, the trajectory of the "dynamic characteristic s" of the data. In this paper, an adaptive time-series modelling method was proposed for short -term dynamic forecasting. The method employs an autoregressive (AR) time-seri es model to carry out the forecasting process. A modified least mean square (MLM S) adaptive filter algorithm was established for adjusting the AR model coeffici ents so as to minimise the sum of squared of forecasting errors. A prototype dyn amic forecasting system was built based on the adaptive time-series modelling m ethod. Basically, the dynamic forecasting system can be divided into two phases, i.e. the Learning Phase and the Application Phase. The learning procedures star t with the determination of upper limit of the adaptation gain based on the conv ergence in the mean square criterion. Hence, the optimum ELMS filter parameters are determined using an iteration algorithm which changes each filter parameter i.e. the order, the adaptation gain andthe values initial coefficient vector on e by one inside a predetermined iteration range. The set of parameters which giv es the minimum value for sum of squared errors within the iteration range is sel ecte

关键词： adaptive time-series model dynamic forecasting production logistics modified least mean square algorithm

The Effect of Dietary Nutrient Density on Growth Performance, Physiological Parameters, and Small Intestinal Type IIb Sodium Phosphate Co-transporter Expression in Broilers

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Journal of Animal Science and Biotechnology 2011年第2期2卷 102-110页

作者： Sidoeun bun State Key Laboratory of Animal Nutrition College of Animal Science and Technology China Agricultural University

A 3 × 4 factorial experiment was con- ducted to determine the effect of dietary nutrient den- sity on growth performance, physiological parame- ters, and small intestinal epithelial phosphate trans- porter expression in broiler chicks fed different dietary nutrient density （DND） and non-phytate phosphorus （NPP） levels. Dietary energy densities used had ME values of 2,850, 2,950, and 3,050 kcal/kg of diet and the NPP levels were 0.35%, 0.40%, 0.45%, and 0.50% within each ME value. Crude protein and essential amino acids levels were maintained propor- tionally to dietary ME levels. Each of the twelve diets was fed to five pens of seven male broiler chicks from 1 to 21 days of age. Broiler growth performance, ser- um physiological parameters, 1-hydroxylase activity in the kidney, type-IIb sodium phosphate co-trans- porter （NaPi-IIb）, and vitamin D receptor （VDR） expression levels in the duodenal mucosa were deter- mined. Our results showed that an increase in dietary nutrient density increased body weight and improved feed conversion. Additionally, serum parathyroid hormone concentration, 1-a-hydroxylase activity in the kidney, NaPi-IIb mRNA expression and VDR protein expression in the duodenal mucosa increased as DND increased. Feed intake and body weight in- creased as NPP levels increased. Serum parathyroid hormone, VDR and NaPi-IIb gene expression also in- creased as the level of NPP in the diet increased at the medium range level. The results of this study suggest that high DND can increase small intestinal type IIb sodium dependent phosphate co-transporter mRNA expression by up-regulating parathyroid hormone and activation of 1-ot-hydroxylase activity which might be in consistent with high growth rate of broilers. Small intestinal NaPi-IIb mRNA expression increases linear- ly only within the range of dietary NPP dosage levels close to the requirement recommended in the broilers feeding standards.

关键词： broiler dietary nutrient density intestinal phosphate transporter non-phytate phosphorus

Erosion and Sediment Disasters in Cambodia1

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Earthquake Research in China 2002年第3期16卷 207-209页

作者： bun Hean Vin bun Pov Ministry of Water Resources and Meteorology Ministry of Water Resources and Meteorology #47 Norodom Blvd. Phnom Penh Cambodia#47 Norodom Blvd. Phnom Penh Cambodia

This report first gives a general description of Cambodia and then discusses its topographic and geological features. Finally, the current situation concerning erosion and sediment disasters is discussed.

关键词： Topographic and geological features Erosion and sediment disasters