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A general information theoretical proof for the second law of thermodynamics

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Science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 813-816页

作者： ZHANG QiRen department of Technical Physics, peking university, beijing 100871,{3. 1. department of Technical Physics Peking University Beijing 100871 China

It is shown that the conservation and the non-additivity of the information, together with the additivity of the entropy, make the entropy increase in an isolated system. The collapse of the entangled quantum state offers an example of the information non-additivity. Nevertheless, the non-additivity of information is also true in other fields in which the interaction information is important. Examples are classical statistical mechanics, social statistics and financial processes. The second law of thermodynamics is thus proven in its most general form. It is exactly true not only in quantum and classical physics but also in other processes in which the information is conservative and non-additive.

关键词： information conservation non-additivity of information entropy increase

Progress in cognitive neuroscientific studies of visual awareness

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Progress in Natural Science:Materials International 2009年第2期19卷 145-152页

作者： Qi Li,Haiyan Geng department of Psychology,peking university,{3. 100871,china [a]department of Psychology Peking University Beijing 100871 China

The psychological and neural mechanisms of consciousness are among the most baffling problems in cognitive neuroscience. In this field,visual awareness is a topic that has been largely investigated,due to easy manipulation and measurable effects. The present arti-cle begins with the phenomena of dissociations between visual awareness and visual stimulus,visual awareness and visual attention,as well as visual awareness and vision-guided behavior,along with the corresponding experimental evidence. Furthermore,the neural mechanism of visual awareness is also discussed. It has been generally believed that visual awareness is the function of higher-order cerebral areas; however,recent discoveries have demonstrated that feedback from higher-to lower-order cortex areas is necessary for generating consciousness. The present article presents an in-depth analysis regarding this feedback process,and exploring its relation-ship with the generation and mechanisms of consciousness. Finally,theoretical controversies and discrepancies,as well as result con-flicts from various studies,have been collected,compared and discussed. Because the field of consciousness continues to be an extremely mysterious and complicated psychological phenomenon,there is a great need for further studies to explore and clarify this topic.

关键词： Visual awareness Neural mechanism Feedback process Cortical areas

Dehydration melting of solid amphibolite at 2.0 GPa: Effects of time and temperature

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Science china Earth sciences 2005年第8期48卷 1120-1133页

作者： ZHOU Wenge1, XIE Hongsen1, LIU Yonggang1, ZHENG Xiaogang1, ZHAO Zhidan2 & ZHOU Hui3.1. Laboratory of Material in the Earth’s Interior, Institute of Geochemistry, Chinese Academy of sciences, Guiyang 550002, china 2. department of Geology, china university of Geosciences, beijing 100083. china 3. department of Geology, peking university, beijing 100871, china 1. Laboratory of Material in the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. department of Geology China University of Geosciences 100083 Beijing China 3. department of Geology Peking University 100871 Beijing China

Two sets of dehydration-melting with a natural solid amphibolite, collected from North Himalayan structure zone, Tibet, have been carried out in multi-anvil apparatus at 2.0 GPa and 800―1000℃, for 12―200 h. One is keeping the pressure at 2.0 GPa and the annealing time of 12 h, changing the temperature (800―1000℃). The other is keeping the pressure at 2.0 GPa and temperature at 850℃, varying the annealing time (12―200 h). The products are inspected with microscope and electron probe. The results indicate that at 2.0 GPa, annealing time of 12 h, garnets, melts and clinopyroxenes occur in amphibolite gradually with increasing temperature and the chemical compositions of melt vary from tonalite to granodiorite, and then to tonalite. However, at 2.0 GPa and 850℃, with the annealing time increasing, the garnets, melts and cli-nopyroxenes also occur in amphibolite gradually and the chemical compositions of melt vary from tonalite to granodiorite. In both cases, melts interconnect with each other when the contents of melt are over the 5 vol.%. the viscosities of the melt produced in amphibolite at temperature higher than 850℃ are on a level with 104 Pa·s. The interconnected melt with such a viscosity may segregate from the source rock and form the magma over reasonable geological time. Therefore, it is believed that at the lower part of the overthickened crust, the tonlitic and grano-dioritic magma may be generated through the dehydration melting of amphibolite.

关键词： solid amphibolite, high pressure, high temperature, time, partial melting.

Experimental measurement of growth patterns on fossil corals:Secular variation in ancient Earth-Sun distances

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Chinese Science Bulletin 2010年第35期55卷 4010-4017页

作者： ZHANG WeiJia1,3.4,LI ZhengBin2,3.& LEI Yang1 1 department of Physics,peking university,{3. 100871,china 2 department of Electrical Engineering and Computer Science,peking university,{3. 100871,china 3.State Key Laboratory of Advanced Optical Communication Systems & Networks,peking university,{3. 100871,china 4 Committee of Yuanpei Honors Program,peking university,{3. 100871,china department of Physics Peking University Beijing 100871 China State Key Laboratory of Advanced Optical Communication Systems & Networks Peking University Beijing 100871 China Committee of Yuanpei Honors Program Peking University Beijing 100871 China department of Electrical Engineering and Computer Science Peking University Beijing 100871 China

In recent years,much attention has been given to the increase in the Earth-Sun distance,with the modern rate reported as 5-15 m/cy on the basis of astronomical ***,traditional methods cannot measure the ancient leaving rates,so a myriad of research attempting to provide explanations were met with unmatched *** this paper we consider that the growth patterns on fossils could reflect the ancient Earth-Sun *** mechanical analysis of both the Earth-Sun and Earth-Moon systems,these patterns confirmed an increase in the Earth-Sun *** a large number of well-preserved specimens and new technology available,both the modern and ancient leaving rates could be measured with high precision,and it was found that the Earth has been leaving the Sun over the past 0.53.billion *** Earth's semi-major axis was 146 million kilometers at the beginning of the Phanerozoic Eon,equating to 97.6% of its current *** modern leaving rates are 5-14 m/cy,whereas the ancient rates were much *** results indicate a special expansion with an average expansion coefficient of 0.57H0 and deceleration in the form of Hubble *** the basis of experimental results,the Earth's semi-major axis could be represented by a simple formula that matches fossil measurements.

关键词：地球太阳古代距离生长模式实验石珊瑚量化

Design of a new dynamical core for global atmospheric models based on some efficient numerical methods

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Science china Mathematics 2004年第z1期47卷 4-21页

作者： WANG Bin, WAN Hui, Jl Zhongzhen, ZHANG Xin, YU Rucong, YU Yongqiang & LIU HongtaoState Key Laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics, Institute of atmospheric Physics, Chinese Academy of sciences, beijing 100029, china department of Computational Mathematics, Academy of Mathematics and System sciences, peking university, beijing 100871, china Chinese Acad Sci Inst Atmospher Phys State Key Lab Numer Modeling Atmospher Sci & Geop Beijing 100029 Peoples R China peking Univ Acad Math & Syst Sci Dept Computat Math Beijing 100871 Peoples R China

A careful study on the integral properties of the primitive hydrostatic balance equations for baroclinic atmosphere is carried out, and a new scheme todesign the global adiabatic model of atmospheric dynamics ispresented. This scheme includes a method of weighted equal-areamesh and a fully discrete finite difference method with quadraticand linear conservations for solving the primitive equationsystem. Using this scheme, we established a new dynamical corewith adjustable high resolution acceptable to the availablecomputer capability, which can be very stable without anyfiltering and smoothing. Especially, some important integralproperties are kept unchanged, such as the anti-symmetries of thehorizontal advection operators and the vertical convectionoperator, the mass conservation, the effective energy conservationunder the standard stratification approximation, and so on. Somenumerical tests on the new dynamical core, respectively regardingits global conservations and its integrated performances inclimatic modeling, incorporated with the physical packagesfrom the Community atmospheric Model Version 2 (CAM2) of NationalCenter for atmospheric Research (NCAR), are included.

关键词： dynamical core, equal-area mesh, anti-symmetry, effective energy conservation.

Raising approximation order of refinable vector by increasing multiplicity

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Science china Mathematics 2006年第1期49卷 86-97页

作者： YANG Shouzhi & PENG Lizhong department of Mathematics, Shantou university, Shantou 515063. china LMAM, School of Mathematical {3., peking university, beijing 100871, china department of Mathematics Shantou University Shantou 515063 China LMAM School of Mathematical Sciences Peking University Beijing 100871 China

An algorithm is presented for raising an approximation order of any given orthogonal multiscaling function with the dilation factor a. Let φ(x) = [φ1(x),φ2(x),…,φr(x)]T be an orthogonal multiscaling function with the dilation factor a and the approximation order m. We can construct a new orthogonal multiscaling function φnew(x) = [ φT(x). f3.+1(x),φr+2(x),…,φr+s(x)}T with the approximation order m + L(L ∈ Z+). In other words, we raise the approximation order of multiscaling function φ(x) by increasing its multiplicity. In addition, we discuss an especial setting. That is, if given an orthogonal multiscaling function φ(x) = [φ1 (x), φ2(x), …, φr(x)]T is symmetric, then the new orthogonal multiscaling function φnew(x) not only raise the approximation order but also preserve symmetry. Finally, some examples are given.

关键词： orthogonal, multiscaling functions, approximation order, symmetry.

Generalized Chow Forms and Reduction of Semi-Stable Varieties

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Acta Mathematica Sinica,English Series 2000年第2期16卷 219-228页

作者： Qingchun Tian department of Mathematics,peking university,{3. 100871,P.R.china department of Mathematics Peking University Beijing 100871 P. R. China

In this note,by using the method of ***[1],we obtain the local version of a theorem of BGS[2]which links Faltings heights of projective varieties with the Philippon heights for the corresponding generalized Chow *** the stable reduction theorem of ***[1],we prove that Chow semistabilities and generalized Chow semistabilities are the same.

关键词： Deligne Pairing Faltings Height Chow forms

Steady States of Some Models for Van derWaals Fluids

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Communications in Nonlinear Science and Numerical Simulation 1998年第3期3卷 163-167页

作者： Shaoqiang TANG(department of Mechanics and Engineering Science, peking university, beijing 100871,{3.) department of Mechanics and Engineering Science Peking University Beijing 100871 China

We study the steady states of some models for van der Waals fluid. Inparticular, for a mass viscosity model, we show that there is no "cavitation’ wave. Wealso consider the closed orbits, heterocliaic orbits, and the... 详细信息

关键词： steady state phase transition mixed-type problem

Asymptotic theory for the MLE from randomly censored exponential samples

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Chinese Science Bulletin 1998年第13期43卷 1071-1076页

作者： WANG Qihua department of Probability and Statistics, peking university, beijing 100871,{3. department of Probability and Statistics Peking University Beijing China

The MLE of the parameter of the exponential population from the censored observations is considered. The Edgeworth expansions for the Studentized MLE are established by representing the relevant statistic as a U\|statistic plus a remainder. A semiparametric bootstrap method is introduced to the random censored model and the accuracy of bootstrap approximation of the MLE is investigated. Furthermore, it is shown that the MLE is asymptotically minimax efficient.

关键词： maximum likelihood estimate Edgeworth expansion bootstrap approximation asymptotic minimax efficiency law of iterated logarithm.