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Advanced information feedback strategy in intelligent two-route traffic flow systems

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science china(Information {2.) 2010年第11期53卷 2265-2271页

作者： DONG ChuanFei1,2. MA Xu1,3.& WANG BingHong1,4 1department of Modern Physics and Nonlinear science Center, University of science and technology of china (USTC), hefei 2.0026, china 2.chool of earth and Atmospheric sciences, Georgia Institute of technology, Atlanta, GA 3.3.2. USA 3.department of Physics, Syracuse University, Syracuse, NY 13.0}4, USA 4The Research Center for Complex System science, University of Shanghai for science and technology and Shanghai Academy of System science, Shanghai 2.0093. china 1. department of Modern Physics and Nonlinear science Center University of Science and Technology of China (USTC) Hefei 230026 China2. School of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta GA 30332 USA3. Department of Physics Syracuse University Syracuse NY 13244 USA4. The Research Center for Complex System Science University of Shanghai for Science and Technology and Shanghai Academy of System Science Shanghai 200093 China

The optimal information feedback has a significant effect on many socioeconomic systems like stock market and traffic systems aiming to make full use of resources. In this paper, we study dynamics of traffic flow with real-time information. The influence of a feedback strategy named vehicle number feedback strategy (VNFS) is introduced, in which we only calculate the vehicle number of first 500 route sites from the entrance. Moreover, the two-route traffic system has only one entrance and one exit, which is different from those in the previous work. Our model incorporates the effects of adaptability into the cellular automaton models of traffic flow, and simulation results by adopting this optimal information feedback strategy have demonstrated higher efficiency in controlling spatial distribution of traffic patterns than the other three information feedback strategies, i.e., TTFS, MVFS and CCFS.

关键词： vehicle number feedback strategy two-route selecting traffic flow intelligent vehicle cellular automaton model

Hamiltonian Formalism of de-Sitter Invariant Special Relativity

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Communications in Theoretical Physics 2007年第7期48卷 27-36页

作者： YAN Mu-Lin XIAO Neng-Chao HUANG Wei Interdisciplinary Center for Theoretical Study,University of science and technology of{2.,{3. 2.0026,chinaLI Si department of Mathematics,University of science and technology of{2.,{3. 2.0026,china Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei 230026 China department of Mathematics University of Science and Technology of China Hefei 230026 China

The Lagrangian of Einstein's special relativity with universal parameter c(SR_c)is invariant under Poincarétransformation,which preserves Lorentz metric η_μν.The SR_c has been extended to be one which is invariant underde Sitter transformation that preserves so-called Beltrami metric B_(μv).There are two universal parameters,c and R,inthis Special Relativity(denoted as SR_(cR)).The Lagrangian-Hamiltonian formulism of SR_(cR) is formulated in this *** canonic energy,canonic momenta,and 10 Noether charges corresponding to the space-time's,de Sitter symmetryare *** canonical quantization of the mechanics for SR_(CR)-free particle is *** physics related to itis discussed.

关键词： de-Sitter invariance special relativity canonic energy and canonic momenta Beltrami metric

Petrogenesis and Geochemistry of Neogene Basalts in Eastern Anhui

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Acta Geologica Sinica(English Edition) 1995年第4期69卷 406-419页

作者： Zhi Xiachen, Chen Daogong and Yang Jindepartment of earth and {2. {3., University of science andtechnology of china, hefei, Anhui Jiang M inxi department of earth and {2. {3. University of Science and Technology of China Hefei Anhui

The basalt terrain of the Neogene Huangguoshan and. Guiwu Formations of eastern Anhui on the east side of the Tancheng-Lujiang fault belt is one of a few Cenozoic basalt terrains in eastern china for which detailed geochemical study has not been conducted. This paper reports the abundances of major elements and more than 2. trace elements (including REE) of 2. samples and the Nd, Sr and Pb isotopic compositions of 11 samples from the eastern Anhui basalt terrain, thus more or less systematically revealing the geochemical characteristics of this continental basalt suite. The paper discusses the origin of the basalt suite and the character and process of its mantle source. The basalt suite was derived from a heterogeneous continental lithospheric mantle with end members characteristic of the EMI-type oceanic basalt mantle, which was affected by mantle metasomatism (or enrichment of trace elements) and was characterized by a multi-stage evolution under open conditions.

关键词： continental alkali basalt EM I-type mantle end-member eastern Anhui

New stylophorans(Echinodermata) from the Upper Cambrian of Guangxi,South china

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science china {2. {3. 2008年第2期51卷 181-186页

作者： HAN NaiRen1 & CHEN GuiYing1,2.1 department of Resources and Environmental Engineering, Guilin University of technology, Gulin 541004,{2. 2.Faculty of earth sciences,{2. University of Geoscience, Wuhan 43.074,{2. department of Resources and Environmental Engineering Guilin University of Technology Gulin 541004 China Faculty of earth sciences China University of Geoscience Wuhan 430074 China

This paper describes for the first time the cornute stylophorans (Echinodermata) in china. The new material came from the Guole Formation of the Furongian (Late Cambrian) in the Guole area of Jingxi, Guangxi Province, South china. These new cornute specimens are preserved in situ and found along with well-preserved trilobites and brachiopods. One new species, Phyllocystis jingxiensis sp. nov., is proposed to accommodate these unusual materials. The new species is defined by the small, heart-shaped theca with the frame composed of ten narrow, smooth and thick marginal plates, three adoral plates and distinctive zygal and aulacophore. Both supracentrals and infracentrals are polygonal-outlined. The marginal plate M1' on the inferior face extends posteriorly to form zygal that possesses a broadened proximal end and the proximal portion joining with the conjunction between M4 and M5 on the inferior face. Aulacophore comprises ten segments at its proximal part and is conical at the middle part (named stylocone). Its distal portion is rather long and bears conspicuous ambulacrum grooves. Tectals are horizontally arranged on superior face and obliquely arranged on inferior face. Both cothurnopore and anal pyramid are vaguely seen on the right anterior corner and the extremity of theca's superior face.

关键词： Phyllocystis Stylophora Echinodermata Cambrian Guangxi South china

A land surface model incorporated with soil freeze/thaw and its application in GAME/Tibet

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science china {2. {3. 2006年第12期49卷 1311-1322页

作者： HU Heping1, YE Baisheng2. ZHOU Yuhua3.& TIAN Fuqiang1 1. department of Hydraulic Engineering, Tsinghua University, Beijing 100084, china 2. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of {2., Lanzhou 73.000, china 3. department of Civil Engineering, Massachusetts Institute of technology, USA 1. department of Hydraulic Engineering Tsinghua University Beijing 100084 China 2. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 3. department of Civil Engineering Massachusetts Institute of Technology USA

Land surface process is of great importance in global climate change, moisture and heat exchange in the interface of the earth and atmosphere, human impacts on the environment and eco- system, etc. Soil freeze/thaw plays an important role in cold land surface processes. In this work the diurnal freeze/thaw effects on energy partition in the context of GAME/Tibet are studied. A sophisti- cated land surface model is developed, the particular aspect of which is its physical consideration of soil freeze/thaw and vapor flux. The simultaneous water and heat transfer soil sub-model not only reflects the water flow from unfrozen zone to frozen fringe in freezing/thawing soil, but also demon- strates the change of moisture and temperature field induced by vapor flux from high temperature zone to low temperature zone, which makes the model applicable for various circumstances. The modified Picard numerical method is employed to help with the water balance and convergence of the numerical scheme. Finally, the model is applied to analyze the diurnal energy and water cycle char- acteristics over the Tibetan Plateau using the Game/Tibet datasets observed in May and July of 1998. Heat and energy transfer simulation shows that: (i) There exists a negative feedback mechanism between soil freeze/thaw and soil temperature/ground heat flux; (ii) during freezing period all three heat fluxes do not vary apparently, in spite of the fact that the negative soil temperature is higher than that not considering soil freeze; (iii) during thawing period, ground heat flux increases, and sensible heat flux decreases, but latent heat flux does not change much; and (iv) during freezing period, soil temperature decreases, though ground heat flux increases.

关键词： land surface model,soil freeze/thaw,GAME/Tibet,simultaneous liquid,vapor and heat transfer.

Research on the dynamics of the South china Sea opening:Evidence from analogue modeling

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science china {2. {3. 2006年第10期49卷 1053-1069页

作者： SUN Zhen1,2. ZHOU Di1, ZHONG Zhihong3. XIA Bin2. QIU Xuelin1, ZENG Zuoxun4 & JIANG Jianqun5 1. CAS Key Laboratory of Marginal Sea Geology, South china Sea Institute of Oceanology, Chinese Academy of {3., Guangzhou 5103.1, china 2. CAS Key Laboratory of Marginal Sea Geology, Guangzhou Institute of Geochemistry, Chinese Academy of {3., Guangzhou 510640, china 3. department of technology, Shenzhen Branch of CNOOC, Guangzhou 5102.0, china 4. Faculty of earth {3., china University of Geo{3., Wuhan 43.074, china 5. Hainan Oil & Gas Exploration Company, Liaohe Oilfield Petrochina, Panjin 12.010, china 1. CAS Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. CAS Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China 3. department of technology Shenzhen Branch of CNOOC Guangzhou 510240 China 4. Faculty of earth sciences China University of Geosciences Wuhan 430074 China 5. Hainan Oil & Gas Exploration Company Liaohe Oilfield PetroChina Panjin 124010 China

Independent of Indochina extrusion, the South china Sea experienced a process from passive continental rifting to marginal sea drifting. According to the fault patterns in the Beibu Gulf basin and the Pearl River Mouth basin, the continental rifting and early spreading stage from 3.2}to 2. Ma were controlled by extensional stress field, which shifted clockwise from southeastward to south southeastward. From 2. Ma on, the sea spread in NW-SE direction and ceased spreading at around 15.5 Ma. Integrated geological information with the assumption that the South china Sea developed along a pre-Cenozoic weakness zone, we did analogue experiments on the South china Sea evolu- tion. Experiments revealed that the pre-existing weakness zone goes roughly along the uplift zone between the present Zhu-1 and Zhu-2.depression. The pre-existing weakness zone is composed of three segments trending NNE, roughly EW and NEE, respectively. The early opening of the South china Sea is accompanied with roughly 15° clockwise rotation, while the SE sub-sea basin opened with SE extension. Tinjar fault was the western boundary of the Nansha block (Dangerous Ground), while Lupar fault was the eastern boundary of the Indochina, NW-trending rift belt known as Zengmu basin developed between above two faults due to block divergent of Indochina from Nansha. In the experiment, transtensional flower structures along NW-trending faults are seen, and slight inversion occurs along some NE-dipping faults. The existence of rigid massifs changed the orientations of some faults and rift belt, and also led to deformation concentrate around the massifs. The rifting and drifting of the South china Sea might be caused by slab pull from the proto South china Sea subducting toward Borneo and/or mantle flow caused by India-Asia collision.

关键词： South china Sea, rifting and drifting, clockwise rotation, analogue modeling, rigid massifs.

Comparison of dark energy models:A perspective from the latest observational data

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中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1631-1645页

作者： LI Miao1,2.LI XiaoDong2.3.& ZHANG Xin1,4 1Kavli Institute for Theoretical Physics china,Chinese Academy of {3.,Beijing 100190,{2. 2.ey Laboratory of Frontiers in Theoretical Physics,Institute of Theoretical Physics,Chinese Academy of {3.,Beijing 100190,{2. 3.nterdisciplinary Center for Theoretical Study,University of science and technology of china,hefei 2.0026,{2. 4department of Physics,College of {3.,Northeastern University,Shenyang 110004,{2. 1. Kavli Institute for Theoretical Physics china Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China3. Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei 230026 China4. Department of Physics College of Sciences Northeastern University Shenyang 110004 China

We compare some popular dark energy models under the assumption of a flat universe by using the latest observational data including the type Ia supernovae Constitution compilation,the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey,the cosmic microwave background measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observations and the determination of H0 from the Hubble space *** comparison statistics such as the Bayesian and Akaike information criteria are applied to assess the worth of the *** statistics favor models that give a good fit with fewer *** on this analysis,we find that the simplest cosmological constant model that has only one free parameter is still preferred by the current *** other dynamical dark energy models,we find that some of them,such as the αdark energy,constant w,generalized Chaplygin gas,Chevalliear-Polarski-Linder parametrization,and holographic dark energy models,can provide good fits to the current data,and three of them,namely,the Ricci dark energy,agegraphic dark energy,and Dvali-Gabadadze-Porrati models,are clearly disfavored by the data.

关键词： dark energy models observational constraints model comparison information criteria

PROPULSIVE PERFORMANCE AND VORTEX SHEDDING OF A FOIL IN FLAPPING MOTION

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Journal of Hydrodynamics 2003年第5期15卷 7-12页

作者： Yang Yan, Lu Xi yun, Yin Xie zhen department of Mechanics and Mechanical Engineering, University of science and {2. of{3., hefei 2.0026,{3., department of Mechanics and Mechanical Engineering University of Science and Technology of China Hefei 230026 China

The propulsive performance and vortex shedding of oscillating foil, whichmimics biological locomotion, were numerically investigated. The objectives of this study were todeal with unsteady force, in particular thrust force, exerted on the foil in pitching and plungingmotions, and to explore the relation of the propulsive performance with vortex structures near thefoil and vortex shedding in the near wake. The two-dimensional incompressible Navier-Stokesequations in the vorticity and stream-function formulation were solved by fourth-order essentiallycompact finite difference schemes for the space derivatives and a fourth-order Runge-Kutta schemefor the time advancement. To reveal the mechanism of the propulsive performance, the unsteady forceand the shedding of the trailing- and leading-edge vortices of the foil were analyzed. The effectsof some typical factors, such as the frequency and amplitude of the oscillation, the phasedifference between the pitching and plunging motions, and the thickness ratio of the foil, on thevortex shedding and unsteady force were discussed.

关键词： vortex dynamics vortex shedding thrust force unsteady flow flappingmotion

Metallogenic geochemistry of Sb-mineralization in southern margin of North china platform

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Chinese science Bulletin 1999年第S2期44卷 17-18页

作者： YANG Xiaoyong~1, YANG Xueming~1, ZHANG Jianjun~2. CAO Gaoshe~2.and ZHANG Zhengwei~2.1. {3. of earth and {2. sciences, University of science and Technlogy of china, hefei 2.0026, china 2. Institute of Geology, Henan Bureau of Geology and Mineral Resources, Zhengzhou 450053. china department of earth and {2. {3. University of Science and Technology of China Hefei 230026 China Institute of Geology Henan Bureau of Geology and Mineral Resources Zhengzhou 450053 China

1 Geological setting THE Sb mineralization zone in the south margin of North china platform is located in the transitional edgeof North china plate and Yangtze plate, belonging to Qinling fold system, whose tectonic line is inNWW-SEE direction regionally. Because of the huge compression caused by the collision of the twoplates, the rocks undergone strong deformation and metamorphism have very complicated structures. Theregional deep fault-Shuanghuaishu fault-controls Sb-mineralization zone belt, and all the Sb-oredeposits or mineralized spots appear alone at the very southern margin of the fault. The lithostragraphirunits in the mineralized zone are relatively simple, mainly composed of Jiebei Group （Pt2./sub>J2./sup>） of QinglingFormation （with middle-high metamorphsim） and the upper Triassic system （with little metamorphism）.

关键词： Sb-mineralization metallognic geochemistry North china plateform.