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Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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science china Chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2. HONG Xiaozhong3. GU Fang1 & BA Xinwu1 1. College of Chemistry and Environment science, Hebei University, Baoding 071002. {3. 2. International Center for Materials Physics, {2. Academy of sciences, Shenyang 110016, {3. 3. College of Physics science and Technology, Hebei University, Baoding 071002. {3. College of Chemistry and Environment science Hebei University Baoding China International Center for Materials Physics Chinese Academy of Sciences Shenyang China College of Physics science and Technology Hebei University Baoding China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

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基于群体共识的动态大群体应急决策方法

系统科学与数学 2024年

作者：梁霞郭洁刘培德刘政敏 1.山东财经大学管理科学与工程学院 2.南京航空航天大学经济与管理学院南京航空航天大学经济与管理学院山东财经大学管理科学与工程学院

为提高应急决策的及时性,决策结果的可靠性和客观性,本文提出一种基于群体共识的动态大群体应急决策方法.首先,利用专家间的意见相似网络构建了考虑子群体内部凝聚力的聚类模型,并进一步探讨了考虑专家评价信息犹豫度的专家权重确定方法... 详细信息

为提高应急决策的及时性,决策结果的可靠性和客观性,本文提出一种基于群体共识的动态大群体应急决策方法.首先,利用专家间的意见相似网络构建了考虑子群体内部凝聚力的聚类模型,并进一步探讨了考虑专家评价信息犹豫度的专家权重确定方法.其次,利用专家间意见相似度和犹豫度建立了个性反馈调整机制用于指导未达成共识的专家调整评价.在上述工作的基础上,构建了考虑专家犹豫行为的动态大群体应急决策方法.最后,通过Z市特大暴雨案例分析验证了本文所提方法的可行性.同时,通过对比分析和仿真分析验证了本文所提方法可以有效的提高决策效率,降低决策的时间成本.

关键词：应急决策大群体群体共识聚类

Gerbes and twisted orbifold quantum cohomology

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science china {2. 2008年第6期51卷 995-1016页

作者： PAN JianZhong~1 RUAN YongBin~(2.3. YIN XiaoQin~(1,3.) 1 Institute of mathematics,Academy of mathematics and {2. science,chinese Academy of sciences,Beijing 100080,china 2.Department of mathematics,University of Wisconsin-Madison,WI 53.06,USA 3.Department of mathematics,The Hong Kong University of science and Technology,Hong Kong,china Institute of mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China Department of mathematics University of Wisconsin-Madison Madison USA Department of mathematics The Hong Kong University of Science and Technology Hong Kong China

In this paper,we construct an orbifold quantum cohomology twisted by a flat gerbe. Then we compute these invariants in the case of a smooth manifold and a discrete torsion on a global quotient orbifold.

关键词： gerbe orbifold quantum cohomology 53.45

Affine bracket algebra theory and algorithms and their applications in mechanical theorem proving

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science china {2. 2007年第7期50卷 941-950页

作者： Ning ZHANG~(1+) Hong-bo LI~2.1 china Institute for Actuarial science (CIAS),Central University of Finance and Economics,Beijing 100081,china 2.Academy of mathematics and systems science,chinese Academy sciences,Beijing 100080,china china Institute for Actuarial science (CIAS) Central University of Finance and Economics Beijing China Academy of mathematics and systems {2. Chinese Academy Sciences Beijing China

This paper discusses two problems:one is some important theories and algorithms of affine bracket algebra;the other is about their applications in mechanical theorem *** we give some efficient algorithms including the boundary expanding algorithm which is a key feature in *** analyze the characteristics of the boundary operator and this is the base for the implementation of the *** also give some new theories or methods about the exact division,the representations and structure of affine geometry and so *** practice,we implement the mechanical auto-proving system in Maple 10 based on the above algorithms and *** we test about more than 100 examples and compare the results with the methods before.

关键词： mechanical theorem proving geometric invariance bracket algebra affine geometry affine bracket algebra 68T15 03.3.

Markov chain approach to identifying Wiener systems

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science china(Information {2.) 2012年第5期55卷 1201-1217页

作者： ZHAO WenXiao 1,2.& CHEN HanFu 1,2.1 Key Laboratory of systems and Control,Institute of systems {2.,AMSS,chinese Academy of sciences,Beijing 100190,china 2.National Center for mathematics and Interdisciplinary sciences,chinese Academy of sciences,Beijing 100190,china Key Laboratory of systems and Control Institute of Systems Science AMSS Chinese Academy of Sciences Beijing China National Center for mathematics and Interdisciplinary sciences Chinese Academy of Sciences Beijing China

Identification of the Wiener system composed of an infinite impulse response (IIR) linear subsystem followed by a static nonlinearity is *** recursive estimates for unknown coefficients of the linear subsystem and for the values of the nonlinear function at any fixed points are given by the stochastic approx-imation algorithms with expanding truncations (SAAWET).With the help of properties of the Markov chain connected with the linear subsystem,all estimates derived in the paper are proved to be strongly *** comparison with the existing results on the topic,the method presented in the paper simplifies the convergence analysis and requires weaker conditions.A numerical example is given,and the simulation results are consistent with the theoretical analysis.

关键词： Wiener system recursive identification stochastic approximation Markov chain strong consis-tency

Range inclusion of operators on non-archimedean Banach space

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science china {2. 2010年第12期53卷 3215-3224页

作者： WANG PengHui 1 & ZHANG Xu 2.3.1 School of mathematics, Shandong University, Jinan 2.0100, {3. 2.Key Laboratory of {2. and Control, Academy of mathematics and {2. science, chinese Academy of sciences, Beijing 100190, {3. 3.School of mathematics, Sichuan University, Chengdu 610064, {3. School of mathematics Shandong University Jinan China Key Laboratory of systems and Control Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China School of mathematics Sichuan University Chengdu China

In this paper, we establish some range inclusion theorems for non-archimedean Banach spaces over general valued fields. These theorems provide close relationship among range inclusion, majorization and factorization for bounded linear operators. It is found that these results depend strongly on a continuous extension property, which is always true in the classical archimedean case, but may fail to hold for the non-archimedean setting. Several counterexamples are given to show that our results are sharp in some sense.

关键词： range inclusion majorization factorization non-archimedean Banach space continuous extension property

The optical near-field speckles and their first order statistics on the basis of the integral equations of electromagnetic field

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science china(Physics,Mechanics & Astronomy) 2004年第3期47卷 365-380页

作者： CHENG Chuanfu1, 2. SONG Hongsheng2. LIU Chunxiang2. REN Xiaorong2. ZHANG Ningyu3. TENG Shuyun1 & XU Zhizhan1 1. Shanghai Institute of Optics and Fine Mechanics, chinese Academy of sciences, P. O. Box 800-2.1, Shanghai 2.1800, {2. 2. Department of Physics, Shandong Normal University, Jinan 2.0014, {2. 3. Shandong Institute of Architecture and Engineering, Jinan 2.0014, {2. Shanghai Institute of Optics and Fine Mechanicschinese Academy of sciencesShanghai{2. Department of PhysicsShandong Normal UniversityJinanchina Shandong Institute of Architecture and EngineeringJinanchina

From Helmholtz equation of the harmonic electromagnetic waves, the integral equations of the light field at the medium boundaries are obtained by use of the Green's theorem and are discretized into linear equation set with the values of the light field and its derivative as the unknowns. On solving the linear equation set, we realize the rigorous computations of the light fields at the boundaries. Then the intensities of the light waves scattered by the random self-affine fractal surfaces in the optical near-field are calculated, and the propagation characteristics, the evolutions of the contrast and the intensity probability density function of the near-field speckles are studied in detail. The near-field speckles are much different from the conventional speckles in the diffraction regions and in the imaging systems. There are obvious local fluctuations in the intensity distributions of the near-field speckles and such fluctuations disappear after propagating a distance of one wavelength from the medium surfaces. For the random surfaces with smaller lateral correlation lengths, the speckle contrasts approach the saturation values and the speckle fields approach Gaussian distribution within the near-field, while for the random surfaces with larger lateral correlation lengths, such evolutions become comparatively slow.

关键词： speckle, near-field optics, first order statistics, Green's function.

Case studies on mesoscale structures of heavy rainfall system in the Yangtze River generated by Meiyu front

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science china Earth {2. 2005年第8期48卷 1303-1311页

作者： LIU Liping1, RUAN Zheng1 & QIN Danyu2.1. chinese Academy of Meteorological sciences, Beijing 100081, {2. 2. Nanjing Institute of Meteorology, Nanjing 2.0044, {2. chinese Academy of Meteorological sciences Beijing China Nanjing Institute of Meteorology Nanjing China

A heavy rainfall system was observed over the Yangtze River during Meiyu season by using dual-Doppler radar systems in the field experiment conducted by the project of National Fundamental Research Planning “Research on formation mechanism and the prediction theory of hazardous weather over china”. The three-dimensional mesoscale kinematic structure and process of a heavy rain on 2. and 2. July, 2.02.are investigated by using the radial velocity and dual-Doppler radar technique. The results show that a southwest-northeast oriented rain band with the length of about 1000 km involves numbers of meso-β or meso-γ-scale convective cells with the size of 2.―50 km. The heavy rain band in the middle reaches of the Yangtze River ex-ists in a low-level wind shear. The interaction between southwest low-level jet on the southern side of wind shear and east wind on the northern side formed the updraft. The wind disturbance, wind shear and convergence generate the convective action. The new cell developed in right rear flank of rain band and moved to the southwest wind area, where the vapor is abundant. This kind of echo can last a long time and developed well. The strong convective echoes are often ac-companied by the meso-γ-scale vortex and convergence.

关键词： heavy rainfall in Meiyu front, mesoscale structure, dual-Doppler radar, middle reaches of the Yangtze River, low-level jet.

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science china Earth {2. 2004年第10期47卷 896-911页

作者： ZHANG Changhou1,2. WU Ganguo1,2. WANG Genhou2. ZHANG Weijie2.& SONG Honglin2.1. Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology, china University of Geosciences, Ministry of Education of china, Beijing 100083. china 2. School of Earth sciences and Mineral Resources, china University of Geosciences, Beijing 100083. china Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology China University of Geosciences Ministry of Education of China Beijing China School of Earth sciences and Mineral Resources China University of Geosciences Beijing China

The northwest trending tectonic belt in the middle part of the Mesozoic intraplate Yanshan Orogenic Belt, northeast Hebei Province, is composed of thrusts, extensional faults, strike-slip faults and syntectonic sedimentations as well. The northeastward basement-involved major thrusting deformation occurred between 174Ma and 168MaBP and was followed by an intrusion of the granitic plutonic rocks. As a part of the post-thrusting extensional deformations a northwest extending volcano-sedimentation system of Late Jurassic and Early Cretaceous formed in the southwest side of the belt. These volcano-sedimentary sequences are divided into Tuchengzi Formation, Zhangjiakou Formation, Yixian Formation and Jiufotang Formation re- spectively. They are characterized by southeastward migration as a result of the increasing down-dip slip displacement along the major extensional fault toward the southeast of the belt. The provenance area of the Jiufotang Formation north to it experienced southwestward thrusting during and after its later sedimentation. The thrusting in this stage resulted in the formation of an asymmetric footwall syncline with vergence to SW in the Jiufotang Formation in the NE side of the basin. Finally a dextral strike-slip deformation occurred along the NW tectonic belt. The striking tectono-geomorphological features and present seismic activities along this belt indicate that it has been being active since Cenozoic era and is still in the active state at present. This northwest extending tectonic belt was following the same direction and location as the existing fault systems within the basement as revealed by former geological and geophysical studies. So it is reasonable to infer the Mesozoic deformation along this belt to be a result of reactivation of the basement structures in a favorable tectonic stress field. The reactivation of basement struc- tures might be taken as one of the mechanisms of intraplate deformation and orogeny.

关键词： Yanshan Orogenic Belt, northwest extending tectonic complex, thrust system, geochronology.