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Journal of Systems science and Systems Engineering 2010年第1期19卷 85-104页

作者： Minghui XU school of Economics and management,wuhan university,wuhan 430072,china school of Economics and management Wuhan University Wuhan China

In this paper, we consider a newsvendor model in which a risk-averse manager faces a stochastic price-dependent demand in either an additive or a multiplicative form. An emergency purchase option is allowed after the realization of demand to satisfy the units that are short. By adopting Conditional value-at-risk （CVaR） as the decision criterion, we aim to investigate the optimal pricing and ordering decisions, and the effects of parameter changes in such a setting. We provide sufficient conditions for the uniqueness of the optimal policy for both demand models. We perforl~, comparative statics analysis to show how the optimal pricing and ordering decision behaves when changing parameters. We also compare our results with those of the newsvendor with a general utility function and with CVaR criterion under lost sales assumption. Our key results include：（i） For both demand models, the optimal selling price is decreasing in risk aversion. Hence, the optimal price of a risk-averse newsvendor is not greater than the optimal price of a risk-neutral newsvendor. （it） In contrary to the lost sales case, for the multiplicative demand model, the optimal order quantity may not be monotonic in risk aversion. Consequently, the optimal risk-averse order quantity may be lower or higher than the optimal risk- neutral counterpart. （iii） For the additive model, the optimal order quantity is strictly increasing in the emergency purchase price, while for the multiplicative model the optimal order quantity has no such a monotonic property. Some numerical examples are conducted to verify our claims and gain more insights about the risk-averse decision-making behaviors.

关键词： Newsvendor model inventory pricing risk aversion conditional value-at-risk

Sol-gel Preparation Copper-cadmium Halide DopedPhotochromic Glass Coating on Plate Glass

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 34-37页

作者： ShiyongLuo Jiayun Zhang Jixiang Liu Metallurgy school, university of science and technology Beijing, Beijing 100083, china wuhan university of technology, wuhan 430070, china Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China wuhan Univ Technol Wuhan 430070 Peoples R China

Copper-cadmium halide doped photochromic glass coating on plate glass has been prepared by a sol-gel process. The sample shows reversible photochromic effect. The results of X-ray diffraction (XRD) and infrared (IR) spectrum investigations indicate that the photochromic phase of tile coating is CuBr_xCl_(1-x), solid solution, and that the structure network of the coating is connected with the bonds of Si-O-Si, Si-O-B and Si-O-Al.

关键词： photochromic glass coating sol-gel photochromic phase, structure network

CABOSFV algorithm for high dimensional sparse data clustering

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Journal of university of science and technology Beijing 2004年第3期11卷 283-288页

作者： Sen Wu Xuedong Gao management school, university of science and technology Beijing, Beijing 100083, china Mgmt. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

An algorithm, Clustering Algorithm Based On Sparse Feature Vector (CABOSFV),was proposed for the high dimensional clustering of binary sparse data. This algorithm compressesthe data effectively by using a tool 'Sparse Feature Vector', thus reduces the data scaleenormously, and can get the clustering result with only one data scan. Both theoretical analysis andempirical tests showed that CABOSFV is of low computational complexity. The algorithm findsclusters in high dimensional large datasets efficiently and handles noise effectively.

关键词： clustering data mining sparse high dimensionality

β-Sialon Produced by Carbon Thermal Nitriding Reaction of Bauxite

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 209-213页

作者： Jun Wang, Nan Li, Caicheng Shi, Chengchang Jia ( Material science and Engineering school, university of science and technology Beijing, Beijing 100083, china Material science and Engineering school, wuhan university of science and technology, wuhan 430 Material science and Engineering school University of Science and Technology Beijing Beijing 100083 China Material science and Engineering school Wuhan University of Science and Technology Wuhan 430081 China

β-Sialon was produced by carbon thermal nitriding reaction in N_2 gas atmosphere when the mixtures of bauxite and anthracite were put into vertical furnace. According to the mass loss of raw materials and the result of X-ray diffration (XRD) of products, the influences of the process parameters on the compositions and relative contents of products, such as the fixed carbon content, the flow of N2, the soaking time and the temperature, were researched.

关键词： β-Sialon bauxite anthracite carbon thermal nitriding processing parameter vertical furnace

Multispectral image fusion method based on intensity-hue-saturation and nonsubsampled three-channels non-separable wavelets

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Chinese Optics Letters 2010年第4期8卷 384-387页

作者：刘斌刘维杰彭嘉雄 school of Mathematics and Computer science hubei university Computer school Wuhan University Institute of Image Recognition and Artificial Intelligence Huazhong University of Science and Technology

A new multispectral image fusion method based on intensity-hue-saturation（IHS） transform and threechannel non-separable wavelets whose dilation matrix is[2,1;1,1]is *** multi-resolution decompositions of the intensity of multispectral image and panchromatic image are performed in nonsubsampled mode using the three-channel non-separable wavelet filter *** approximation images and the detail images of the multi-resolution pyramids are *** experimental results show that this method has good visual *** performance outperforms the IHS fusion *** discrete wavelet transform （DWT） fusion method,and the IHS-DWT fusion method in preserving spectral quality and high spatial resolution information.

关键词： Decomposition Discrete wavelet transforms Filter banks Visual communication

An architecture for mobile database management system

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Journal of university of science and technology Beijing 2002年第2期9卷 156-160页

作者： Dong Li and Yucai Feng Computer school, Huazhong university of science and technology, wuhan 430074, china Computer school Huazhong University of Science and Technology Wuhan 430074 China

In order to design a new kind of mobile database management system (DBMS)more suitable for mobile computing than the existent DBMS, the essence of database systems in mobilecomputing is analyzed. An opinion is introduced that the mobile database is a kind of dynamicdistributed database, and the concept of virtual servers to translate the clients' mobility to theservers' mobility is proposed. Based on these opinions, a kind of architecture of mobile DBMS, whichis of versatility, is presented. The architecture is composed of a virtual server and a local DBMS,the virtual server is the kernel of the architecture and its functions are described. Eventually,the server kernel of a mobile DBMS prototype is illustrated.

关键词： mobile database dynamic distributed database DBMS architecture virtual server data region

Numerical simulations and experimental investigations on transverse effects of two-wave mixing in a photovoltaic photorefractive crystal

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science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 856-863页

作者： CAI Xin1,2,LIU JinSong1 & WANG ShengLie1 1 wuhan National Laboratory for Optoelectronics,school of Optoelectronic science and Engineering,Huazhong university of science and technology,wuhan 430074,china 2 school of science,wuhan university of technology,wuhan 430070,china 1. wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China2. School of Science Wuhan University of Technology Wuhan 430070 China

The transverse effects of two Gauss waves mixing in a photovoltaic photorefractive crystal,i.e.,the dynamical evolutions of signal beam with different parameters,are traced numerically and *** the one-dimensional numerical simulations and two-dimensional experimental investigations show that the self-focusing effect of signal beam becomes more obvious as the intensity of pump beam and the angle between the signal and pump beams *** accordance with these results,the state of two Gaussian waves mixing is controllable.

关键词： numerical simulation experimental investigation two-wave mixing transverse effects Gaussian distribution

Analysis of the Difference of the Basic Pension by Regions

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Chinese Journal of Population,Resources and Environment 2007年第2期5卷 84-87页

作者： Ye Hanxiong, Wu Xiangling school of Political science and Public management, wuhan university, wuhan hubei 430072, china school of Political science and Public management Wuhan University Hubei 430072 Wuhan China

Nowadays, the disparity of the basic pension in local regions of china can be described as follows: the low level of the unification of the basic pension systems, the large disparity of the level of the basic pension, and unfairness of the enterprises’ payment for the basic pension in different local regions in china. These have already brought many negative influences, which have greatly held back the development of the society and national economy. We should build the basic pension system in all local regions of china as a whole, which can cover all people and decrease the disparity in different local regions in china.

关键词： the basic pension the disparity in the local regions harmonious development

Blank design optimization for stepped-section profile ring rolling

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science china(Technological sciences) 2010年第6期53卷 1612-1619页

作者： QIAN DongSheng & HUA Lin school of Materials science and Engineering,wuhan university of technology,wuhan 430070,china 1. school of Materials science and Engineering Wuhan University of Technology Wuhan 430070 China

A stepped-section ring consists of two rectangular section rings,a big ring and a small ring,joined *** kind of ring is difficult to process by the ring rolling technique because of its complex cross-sectional *** a reasonable blank design is *** this paper,four blank designs,one is a rectangular cross-section and the other three are stepped-sections with different step volumes,are proposed and compared with each other using theoretical analysis,FE simulation and *** is shown that three of the designs can lead to volume flow from small ring into big ring during rolling,which is disadvantageous for shape formation and dimensional precision;however,the other design may result in good ring shape and high dimensional ***,the optimal blank design is determined to be the one in which the volumes of the big and small rings of the initial blank are equal to those of the final rings,respectively.

关键词： ring rolling stepped-section ring optimization design FE simulation