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Comparisons of EVD and DVD

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 74-78页

作者： YAN Ming dai jian-hua HU Guo-rong GxSOC Research Institute Communication University of China Beijing 100024 P.R. China

The goal of the Enhanced Versatile Disc （EVD） standard is to define an advanced high definition disc competing with Digital Versatile Disc （DVD）. The EVD standard consists of the physical specification, the file system .specification, and the specification for audio/video data and Enhanced （ x ） Audio Coding （ExAC） technology. EVD is an integrated .system similar to DVD. Comprehensive comparisons of EVD and DVD are given in this paper. Their key differences include disc formats, file system structures, data structures, audio/video coding, and other issues. Among them, we emphasize on the logic structure of EVD data and its enhanced audio coding method ExAC. We can draw conclusions through these comparisons that EVD is more the advantageous.

关键词： EVD DVD logic structure ExAC MPEG-2

Hysteresis Loop of Energy Transfer in Two-Wave Mixing from 180° Domains in BaTiO_(3):Ce

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Chinese Physics Letters 1997年第2期14卷 100-102页

作者： WU jian-lao dai jian-hua ZHANG Hong-jun Laboratory of Optical Physics Institute of Physics&Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080

This paper reports an experimental observation that a hysteresis loop of energy transfer versus an external electric field is obtained in photorefractive two-wave mixing,which originates from 180°domains presented in... 详细信息

关键词： crystal. mixing hysteresis

Photorefractive Mutually-Pumped Phase Conjugation with Coherent Beams: Sensitivity to Small Perturbations

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Chinese Physics Letters 1999年第12期16卷 899-901页

作者： SHEN Jing-ling dai jian-hua ZHANG Hong-jun Laboratory of Optical Physics Institute of PhysicsChinese Academy of SciencesBeijing 100080 Department of Physics Capital Normal UniversityBeijing 100037

Mutually-pumped phase conjugation in BaTiO3 crystal with two coherent incident beams has been studied experimentally for the bridge configuration. We observed that when the two pump beams are blocked individually, the transient behavior of the phase conjugation reflectivity with coherent beams was greatly different from that with incoherent beams. The phase conjugate reflectivity was sensitive to small perturbations such as vibration, exhibiting a change of as much as a factor of 10. The response time to the vibration was measured to be about 0.3s.

关键词： coherent reflectivity conjugate

Minimal axiom group of similarity-based rough set model

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Frontiers of Electrical and Electronic Engineering in China 2006年第3期1卷 255-258页

作者： dai jian-hua PAN Yun-he Institute of Artificial Intelligence Zhejiang UniversityHangzhou 310027China

Rough set axiomatization is one aspect of rough set study to characterize rough set theory using dependable and minimal axiom ***,rough set theory can be studied by logic and axiom system *** classical rough set theory is based on equivalence relation,but the rough set theory based on similarity relation has wide ap-plications in the real *** characterize similarity-based rough set theory,an axiom group named S,consisting of 3 axioms,is *** reliability of the axiom group,which shows that characterizing of rough set theory based on similarity relation is rational,is ***,the minimization of the axiom group,which requests that each axiom is an equation and independent,is *** axiom group is helpful to research rough set theory by logic and axiom system methods.

关键词： rough set theory axioms minimization

Anomalous Emission And Carrier Effect of Fresh Porous Silicon

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Chemical Research in Chinese Universities 2002年第3期18卷 270-273页

作者： ZOU Bing-suo WU Zhen yu CAO Li dai jian-hua XIE Si-shen WANG jian ping Mostafa AEl-Sayed Optical Lab Institute of PhysicsChinese Academy of SciencesBeijing 100080P.R.China Laser Dynamics Laboratory School of Chemistry and BiochemistryGeorgia Institute of TechnologyAtlantaGA30332-0400

The emission and Fourier transformation infrared spectra of freshly prepared porous silicon(PS) and the silicon wafer were examined. Increasing temperature generally led to a decrease in the emission intensities of the PS samples, however, the freshly prepared sample showed an unusually large and sudden increase in its emission intensity at the specific temperature at which the hydrogen ion conductivity in the silicon wafer increased. The O-H vibrations of the silicon wafer also showed a sudden decrease at the same temperature. These results are consistent with the assumption that the luminescence of fresh PS comes from the carrier bound exciton in its confined nanostructure.

关键词： Porous silicon Silicon wafer Carrier effect

Manifestation of Quantum Chaos in the Spectra of Quantum Well with Tilted Magnetic Field

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Chinese Physics Letters 1999年第2期16卷 140-142页

作者： LIU Bo dai jian-hua ZHANG Guang-cai ZHANG Hong-jun Laboratory of Optical Physics Institute of Physics&Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080

Two statistical properties,the nearest neighbor energy level spacing distribution P(s)and the spectral rigidityΔ3(L),are reported for energy level of a quantum well in a tilted magnetic ***-reversal(T)symmetry is broken in the *** system is invariant under the anti-unitary combination of symmetric operations which include T,leading to what is called false *** the increasing magnetic field,P(s)andΔ3(L)change from Brody type-like distribution to the Gaussian orthogonal ensemble(GOE)*** result is a clear manifestation of quantum chaos in the system and is in agreement with the prediction of which the false T-violation suffices to give the energy spectra the properties of the GOE,instead of the Gaussian unitary ensemble(GUE).The result indicates that the system translates from mixed-type state to quantum chaotic ***,the spectral rigidityΔ3(L)turns into GUE with the magnetic field *** different demonstration of P(s)and theΔ3(L)is due to the counting of only finite semi-classical orbits.

关键词： field. quantum unitary

Eigenvalues and Eigenfunctions of a Stadium-Shaped Quantum Dot Subjected to a Perpendicular Magnetic Field

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Chinese Physics Letters 1998年第9期15卷 628-630页

作者： LIU Bo ZHANG Guang-cai dai jian-hua ZHANG Hong-jun Laboratory of the Optical Physics Institute of Physics&Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080

The eigenvalues and eigenfunctions of the stadium-shaped quantum dot subjected to a constant magnetic field in the perpendicular direction are computed by a simple and efficient *** the magnetic field increasing,the nearest-neighour-energy-level-spacing distribution of the stadium-shaped quantum dot is found to transform gradually from the Wigner distribution to the Poisson *** transition of the nearest-neighour-energy-level-spacing distribution indicates that system changes from quantum chaotic to *** variation of the spatial charge distribution indicates that the system varies from bulk Landau state to the edge state that mainly affects the transport properties of the stadium-shaped quantum *** change of the two dimensional charge distribution near the anticrossing point is also discussed.

关键词： method. quantum shaped

Relationship between alanine aminotransferase levels and metabolic syndrome in nonalcoholic fatty liver disease

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第8期9卷 616-622页

作者： Zhou-wen CHEN Li-ying CHEN Hong-lei dai jian-hua CHEN Li-zheng FANG Department of General Practice Sir Run Run Shaw Hospital School of Medicine Zhejiang University Hangzhou 310016 China

Objective： To investigate the relationship between alanine aminotransferase （ALT） levels and metabolic syndrome （MS） in nonalcoholic fatty liver disease （NAFLD）. Methods： A total of 26527 subjects who received medical health checkup in our hospital from January 2005 to July 2007 were enrolled in the study. The diagnosis of fatty liver was based on ultrasound imaging. MS was defined according to the criteria of the Adult Treatment Panel III. ALT, triglyceride （TG）, high density lipoprotein cholesterol （HDL-c）, fasting plasma glucose （FPG）, height, weight, waist circumference （WC）, systolic blood pressure （SBP） and diastolic blood pressure （DBP） were measured in each subject to analyze the relationship between MS and ALT activity Results：（1） The prevalence of NAFLD in men （30.94%） was significantly higher than that in women （15.65%）; （2） The incidence of MS in NAFLD （33.83%） was significantly greater than that in non-NAFLD （10.62%）; （3） Of the 6470 subjects with NAFLD, in the age-adjusted partial correlation analysis, there were statistically significant correlations between the ALT levels and most metabolic risk factors in each sex （P〈0.01）, except that ALT levels multiple stepwise regression analysis, SBP lost its significance, and had no correlation with HDL-c in women. Moreover, in the WC, body mass index （BMI）, age, DBP, TG and FPG were independently associated with ALT levels in both sexes （P〈0.05）. HDL-c remained significant and was independently related to ALT levels in men; （4） ALT levels were significantly higher in subjects with MS compared to those without MS （P〈0.001）. Mean ALT levels increased with the number of MS components in each sex （P〈0.05 for trend）. Conclusion： We found a strong relationship between ALT levels and MS in NAFLD and revealed that the cluster of MS components might be the predictor for ALT elevations.

关键词： Nonalcoholic fatty liver disease (NAFLD) Alanine aminotransferase (ALT) Metabolic syndrome (MS)

Immune algorithm for discretization of decision systems in rough set theory

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第4期7卷 602-606页

作者： JIA Ping dai jian-hua CHEN Wei-dong PAN Yun-he ZHU Miao-liang Institute of Artificial Intelligence Zhejiang University Hangzhou 310027 China

Rough set theory plays an important role in knowledge discovery, but cannot deal with continuous attributes, thus discretization is a problem which we cannot neglect. And discretization of decision systems in rough set theory has some particular characteristics. Consistency must be satisfied and cuts for discretization is expected to be as small as possible. Consistent and minimal discretization problem is NP-complete. In this paper, an immune algorithm for the problem is proposed. The correctness and effectiveness were shown in experiments. The discretization method presented in this paper can also be used as a data pre- treating step for other symbolic knowledge discovery or machine learning methods other than rough set theory.

关键词： Rough sets Discretization Immune algorithm Decision system