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The information entropy of a static dilaton black hole

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Science china(physics,Mechanics & Astronomy) 2008年第2期51卷 113-125页

作者： LIU ChengZhou Institute of Theoretical physics, Binzhou university, Binzhou 256600, china department of physics, Beijing Normal university, Beijing 100875, china Institute of Theoretical physics Binzhou University Binzhou China department of physics Beijing Normal University Beijing China

In accordance with holographic principle, by calculating the statistical entropy of the quantum field just at the event horizon of the Garfinkle-Horowitz-Strominger dilaton black hole, the information entropy of the black hole was investigated and the Bekenstein-Hawking formula was obtained. The results show that black hole entropy is identical with the statistical entropy of the quantum field at the horizon. Using the generalized uncertainty relation, the divergence of the state density near the event horizon in usual quantum field theory was removed, and the cutoffs and the little mass approximation in the heat gas method of black hole entropy were avoided. Thus, the microstates of the massive scalar field just at the event horizon of the static dilaton black hole were studied directly and a description on holograph principle was presented. By using residue theorem, the integral difficulty in the calculation was overcome, and the information entropy and the Bekenstein-Hawking formula were obtained quantitatively. Compared with the black hole entropy from the loop quantum gravity, the consistency of methods and results of calculating black hole entropy in non-commutative quantum field theory and loop quantum gravity was investigated. By this, the gravity correction constant in the generalized uncertainty relation was suggested and the sense of holographic principle was discussed.

关键词： black hole entropy holographic principle non-commutative quantum field theory event horizon loop quantum gravity

Langevin Treatment of Atomic Coherence Effect on Hybrid Erbium doped Fiber Amplification

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Chinese Journal of Lasers 1999年第6期8卷 3-5页

作者： LIU Fangxin 1,3 GUO Yang 2 MING Hai 2 ( 1 Structure Research Laboratory, 2.department of physics, 3 department of Astronomy and Applied physics, university of Science and Technology of china, Hefei 230026, china) 中国科学技术大学结构研究实验室结构分析开放实验室安徽合肥 230026 中国科学技术大学物理系安徽合肥

The effects of atomic coherence on hybrid erbium doped fiber amplifier (HEDFA) pumped simultaneously by two diode lasers with different frequencies are studied by using Langevin quantum theory. The expressions of coherence and incoherence gain are derived. The theoretical results show that HEDFA has a near flat bandwidth response from 1531 to 1568 nm and large coherence gain under the conditions of low temperature and small detuning.

关键词： atomic coherence hybrid erbium doped fiber amplifier LD pump

From the Green's Function in Tight-Binding Representation to Interatomic Many-body Potentials

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Journal of Materials Science & Technology 1999年第4期15卷 315-319页

作者： Shaojun LIU(department of physics, Beijing Normal university, Beijing 100875, china)Xiaobo WEI(department of physics, Liuzhou College of Education, Liuzhou 545005, china)Zhaodou CHEN Jun CAI and Benkun MA(department of physics, Beijing Normal university, department of physics Beijing Normal University Beijing 100875 China department of physics Liuzhou College of Education Liuzhou 545005 China

In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hopping integrals which are the physical origin of cohesion of atoms. For thesimple case of s-valent system, the inversion of the many-body potentials are discussed in detail by using the lattice inversion method.

关键词： Rev Li Chen From the Green’s Function in Tight-Binding Representation to Interatomic Many-body Potentials body

Improvement of the classification accuracy in discriminating diabetic retinopathy by multifocal electroretinogram analysis

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Progress in Natural Science:Materials International 2007年第8期17卷 913-918页

作者： Xu Jin~1 Hu Guangshu~(1**) Huang Houbin~2 (1.department of Biomedical Engineering,Tsinghua university,Beijing 100084,china 2.department of Ophthalmology,General Hospital of Chinese PLA,Beijing 100853,china) department of Biomedical Engineering Tsinghua University Beijing 100084 China department of Ophthalmology General Hospital of Chinese PLA Beijing 100853 China

The multifocal electroretinogram (mfERG) is a newly developed electrophysiological *** this paper,a classifi- cation method is proposed for early diagnosis of the diabetic retinopathy using mfERG *** records were obtained from eyes of healthy individuals and patients with diabetes at different *** each mfERG record,103 local responses were *** value of each point on all the mfERG local responses was looked as one potential feature to classify the experimental *** sub- sets were selected from the feature space by comparing the inter-intra *** on the selected feature subset,Fisher's linear classi- fiers were *** the final classification decision of the record was made by voting all the classifiers' *** the method to classify all experimental subjects,very low error rates were *** crucial properties of the diabetic retinopathy classification method are also discussed.

关键词： diabetic retinopathy multifocal electroretinogram feature selection linear classifier

HYDRODYNAMIC SIMULATION TO MOLD FILLING UNDER COUNTER GRAVITY

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Acta Metallurgica Sinica(English Letters) 2000年第2期13卷 780-783页

作者： J.M. Zeng and Y.H. Zhou 1) Institute of Materials Science, guangxi university, nanning 530004, china 2) department of Materials Science and Engineering, Shanghai Jiao Tong university, Shanghai 200030, china

In situ observations of the flow morphology during mold filling under counter gravity are conducted on a perspex water model by means of flow visualization, high speed photography and pattern processing. The experimental results indicate that influences of the dynamic factors on flow morphology can be expressed quantitatively with the parameterφ(k). The flow field takes on different morphology with change in values of φ(k). For thick and thin walled castings, the main dynamic factors influencing flow morphology are gravity and surface tension respectively. Under general circumstances, F_r and W_e should be equal in their values to guarantee the similarity between the prototype and the model in simulating mold filling under counter gravity by experiment.

关键词： casting mold filling hydrodynamics

Dynamics of Spin-2 Bose-Einstein Condensates

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Communications in Theoretical physics 2007年第12期48卷 1041-1046页

作者： HOU Jing-Min department of physics,Southeast university,Nanjing 211189,china department of physics Southeast University Nanjing 211189 China

We numerically simulate the dynamics of a spin-2 Bose-Einstein *** find that the initialphase plays an important role in the spin component *** spin mixing processes can fully cancel out due toquantum interference when taking some initial special *** all the spin mixing processes,the total spin is *** the initial population is mainly occupied by a component with the maximal or minimal magnetic quantum number,the oscillations of spin components cannot happen due to the total spin *** presence of quadratic Zeemanenergy terms suppresses some spin mixing processes so that the oscillations of spin components are suppressed in someinitial spin ***,the linear Zeeman energy terms have no effects on the spin mixing processes.

关键词： spinor Bose-Einstein condensates dynamics spin mixing

Relations Between Characteristic Function,Positive P-Representation and Coherent Thermal State

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Communications in Theoretical physics 2007年第7期48卷 67-70页

作者： FAN Hong-Yi XU Xing-Lei department of Material Science and Engineering,university of Science and Technology of china,Hefei 230026,china2.department of physics,Shanghai Jiao Tong university,Shanghai 200030,china3 department of physics,Heze university,Heze 274015,china department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China department of physics Shanghai Jiao Tong University Shanghai 200030 China department of physics Heze University Heze 274015 China

We employ the coherent thermal states(a kind of entangled states)in thermal field dynamics to establisha complete entangled state formalism expressing pseudo-classical representations of density operator for light ***,the relationship between the coherent thermal state and the characteristic function and the positive Prepresentation in quantum optics theory are obtained.

关键词： coherent thermal state characteristic function positive P-representation

Investigation on the High Temperature Internal Friction of a Subperitectic Al-Zr Alloy in Precipitating Process of ZrAl_3

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Rare Metals 1989年第3期9卷 20-26页

作者： Teng Gongqing Huang Changzhi department of physics,Northeast university of Technology,Shenyang,china Northeast Univ of Technology China

An inverted torsion pendulum has been used to study the high temperature internal friction of an Al-0.22wt% Zr *** experimental result has shown that the grain boundary internal friction peak shifted to lower temperature,the peak height des- cended and the activation energy related to this peak increased in the precipitating process of ZrAl_3 particle in the ***- while,the high temperature background descended so obviously as to be separated from the grain boundary internal *** internal friction peak caused by diffusion around ZrAl_3 particles has been *** mechanism of improvement of proper. ties of aluminium alloys containing a small amount of zirconium has also been discussed.

关键词： Zr Al

On the generalized Busemann-Petty problem

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Science china Mathematics 2007年第8期50卷 1103-1116页

作者： Song-jun L~(1,2+) Gang-song LENG~1 1.College of Mathematics and Computer Science,Chongqing Normal university,Chongqin 400047,china 2.department of Mathematics,Shanghai university,Shanghai 200444,china College of Mathematics and Computer Science Chongqing Normal University Chongqin China department of Mathematics Shanghai University Shanghai China

The generalized Busemann-Petty problem asks whether the origin-symmetric convex bodies in ? n with a larger volume of all i-dimensional sections necessarily have a larger volume. As proved by Bourgain and Zhang, the answer to this question is negative if i > 3. The problem is still open for i = 2, 3. In this article we prove two specific affirmative answers to the generalized Busemann-Petty problem if the body with a smaller i-dimensional volume belongs to given classes. Our results generalize Zhang’s specific affirmative answer to the generalized Busemann-Petty problem.

关键词： star body cross i-section dual mixed volume Radon transform 52A30 52A40