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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

A New Clustering Algorithm for Categorical Attributes

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 318-322页

作者： Songfeng Lu, Zhengding Lu (college of Computer science and technology, Huazhong university of science and technology, wuhan 430074, china) college of Computer science and technology Huazhong University of Science and Technology Wuhan 430074 China

In traditional data clustering, similarity of a cluster of objects is measured by distance between objects. Such measures are not appropriate for categorical data. A new clustering criterion to determine the similarity between points with categorical attributes is pre- sented. Furthermore, a new clustering algorithm for categorical attributes is addressed. A single scan of the dataset yields a good clus- tering, and more additional passes can be used to improve the quality further.

关键词： data mining clustering similarity Information

DOUBLE Φ-FUNCTION INEQUALITY FOR NONNEGATIVE SUBMARTINGALES

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 211-216页

作者： MEI TAO(college of Mathematics and Computer sciences, wuhan university, wuhan 430072, china.) LIU PEIDE(college of Mathematics and Computer sciences, wuhan university, wuhan 430072, china.) college of Mathematics and Computer sciences Wuhan University Wuhan 430072 China

The authors establish a kind of inequalities for nonnegative submartingales which depend on two functions　ψ and ψ, and obtain the equivalent conditions for　Φ and ψ such that this kind of inequalities holds. In t... 详细信息

关键词： Matingale Nonnegative submartingale Maximal function Φ-function inequality

A quasi-physical algorithm for solving the linear separation problem in n-dimensional space

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Journal of Central South university of technology 2001年第4期8卷 272-277页

作者： HUANG Jia yuan (college of Computer science, Huazhong university of science and technology, wuhan 430074, china) 1. college of Computer science Huazhong University of Science and Technology 430074 Wuhan China

A quasi physical algorithm was proposed for solving the linear separation problem of point set in n dimensional *** original idea of the quasi physical algorithm is to find an equivalent physical world for the primitive mathematical problem and to observe the vivid images of the motion of matter in it so as to be inspired to obtain an algorithm for solving the mathematical problem. In this work, the electrostatics with two kinds of matter is found to be the equivalent physical world. As a result,the proposed algorithm is evidently more efficient and robust than the famous LMS algorithm and ETL algorithm. The efficiency of the quasi physical algorithm is about 10-50 times of the LMS algorithm’s for representative instances. A typical Boolean valued instance shows that it is hard for ETL algorithm but very easy for the quasi physical *** this instance, point set A and B is {000, 010, 011, 111} and {001,100}, respectively.

关键词： linear separation problem neural network algorithm quasi-physical method electrostatics

Fractal Nature of Crack Growth under Different Temperature

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Journal of Materials science & technology 1996年第2期12卷 143-148页

作者： Qunsheng CAO (Dept. of Physics, wuhan Yejin university of science & technology, wuhan 430081, china) Dept. of Physics Wuhan Yejin University of Science and Technology Wuhan 430081 China

We have studied numerically a simple crack growth model in a two-dimensional triangular lattice of bonds and nodes which incorporates the surface of a growing crack bond-breaking probability P-i similar to exp{(-V-i+E(i))phi(T)}, where E(i) is elastic energy stored in the i-th bond. Different energy temperature factors phi(T) are employed during crack formation and propagation process with a uniform dilation strain case and a shear case and with periodic boundary condition in the horizontal direction. Our results show that the patterns of the cracks generated are fractal structure and the effective fractal dimensionalities decrease with the increase of the temperature factor phi(T)(the absolute temperature T decreasing). In the paper we also discuss the relation between the effective fractal dimension D-eff (the radius R(g) of gyration) and the fractal dimensions D (the radius R of circular), and also give their modification values Omega about two kinds of methods in the lattice model.

关键词： Nature Fractal Nature of Crack Growth under Different Temperature

The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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science china(Technological sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1, QIAN Yingping1,3, WANG Guilan1 & ZHENG Qiguang2 1. School of Material science and technology, Huazhong university of science and technology, wuhan 430074, china 2. Institute of Laser technology and Engineering, Huazhong university of science and technology, wuhan 430074, china 3. Mechanical Engineering college, Hubei university of technology, wuhan 430068, china 1. School of Material science and technology Huazhong University of Science and Technology Wuhan 430074 China 3. Mechanical Engineering college Hubei University of Technology Wuhan 430068 China 2. Institute of Laser technology and Engineering Huazhong University of Science and Technology Wuhan 430074 China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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wuhan university Journal of Natural sciences 2002年第1期7卷 107-112页

作者： Zheng Hua 1 , Du Yu-min 2 1. Department of Chemical Engineering, wuhan university of technology, wuhan 430070, Hubei, china 2. college of Chemistry and Molecular sciences, wuhan university, wuhan 430072, Hubei, china wuhan university of technology Department of Chemical Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2%(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 30°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 30%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization

Ferroelectric properties of Bi_(3.4)Ho_(0.6)Ti_3O_(12) thin films prepared by sol-gel method

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science china(Technological sciences) 2008年第9期51卷 1439-1444页

作者： FU ChengJu1, HUANG ZhiXiong1, LI Jie2 & GUO DongYun3 1 School of Materials science and technology, wuhan university of technology, wuhan 430070, china 2 School of Mechanical Engineering, Chongqing university of science and technology, Chongqing 400050, china 3 Department of Physics, wuhan university, wuhan 430072, china School of Materials science and technology Wuhan University of Technology Wuhan 430070 China School of Mechanical Engineering Chongqing University of Science and Technology Chongqing 400050 China Department of Physics Wuhan University Wuhan 430072 China

We have prepared the Ho-substituted bismuth titanate (Bi3.4Ho0.6Ti3O12, BHT) thin films on Pt/Ti/SiO2/Si substrates using sol-gel method. The crystal structure and morphology of the films were characterized using X-ray diffraction and atomic force microscopy. The BHT film shows a single phase of Bi-layered Aurivillius structure and dense microstructure. The 2Pr and 2Ec of the 600-nm-thick BHT film were 38.4 μC/cm2 and 376.1 kV/cm, respectively at applied electric field 500 kV/cm. The dielectric constant and dielectric loss are about 310 and 0.015 at a frequency of 1 MHz, respectively. The Pr value decreased to 93% of its pre-fatigue values after 4.46×109 switching cycles at 1 MHz frenquency, and the BHT film shows good in-sulating behavior according to the test of leakage current.

关键词： Bi3.4Ho0.6Ti3O12 thin film sol-gel method ferroelectric property fatigue dielectric constant

Refrigerant Control Strategies for Residential Air-Conditioning and Heat-Pump System

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湖南大学学报（自然科学版） 2009年第S1期36卷 91-95页

作者： SU Shun-yu,ZHANG Chun-zhi,CHEN Jian(college of Urban Construction,wuhan university of science and technology,wuhan,Hubei 430070,china) college of Urban Construction Wuhan University of Science and Technology Wuhan 430070 China

This paper simulated the optimal refrigerant charge inventory of a refrigeration system in air-conditioning operation and heat-pump operation respectively,and studied the refrigerant control strategies in this *** void fraction in two-phase fluid region was calculated by Harms *** based on distributed parameter model and Harms model,the refrigerant charge inventory in condenser and evaporator were calculated and analyzed in air-conditioning conditions and heat-pump conditions,*** calculating results of different refrigerant mass between refrigeration and heating conditions indicate that the optimal refrigerant charge inventory in heat-pump conditions is lower than that in air-conditioning *** avoid the decrease of COP due to the surplus refrigerant in heating conditions,we introduced the liquid reservoir control method and associate capillary control *** of them could increase the heating capacity of the air-source heat *** difference of optimal refrigerant charge inventory in air-conditioning and heat-pump system can be controlled by the liquid reservoir or the associate capillary.

关键词： air-source heat pump control strategy distributed parameter model charge inventory

Peplomycin induces G1-phase specific apoptosis in liver carcinoma cell line Bel-7402 involving G2-phase arrest

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Acta Pharmacologica Sinica 2004年第12期25卷 132-138页

作者： Hong-ying CHEN2, Cong-yi ZHENG2, Guo-lin ZOU2, Da-xing XIE3, Jian-ping GONG3 2college of Life sciences, wuhan university, wuhan 430072 3Cancer Research Institute, Tongji Hospital, TongjiMedical college, Huazhong university of science and technology, wuhan 430072, china college of Life sciences Wuhan University Wuhan 430072 China

AIM: To investigate the mechanism of peplomycin (PEP)-induced apoptosis in liver carcinoma cell line (Bel-7402). METHODS: Growth inhibition by PEP was analyzed using 3- 4,5-Dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptotic cells were detected using Hoechest 33258 staining, and confirmed by flow cytometric analysis and DNA fragmentation analysis. The expression of cyclin A and B1 were determined by flow cytometry and Western blot. Annexin V assay was measured by flow cytometric analysis. RESULTS: PEP induced apoptosis and then inhibited cell proliferation in liver carcinoma cell line Bel-7402. Cells treated with PEP 50 μmol/Lfor 15 h were arrested in G2-phase with dramatical expression of cyclin A and a little change in cyclin B1. Almost all the apoptosis occurred in cells undergoing the G1-phase after treatment for 24 h. CONCLUSION: Peplomycin induced G1-phase specific apoptosis in Bel-7402 involving G2-phase arrest.

关键词： peplomycin Bel-7402 cells apoptosis cyclins cell cycle flow cytometry