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Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists’ Spatial Behavior Simulator Based on GIS and Multi-Agent System

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Wuhan University Journal of Natural sciences 2005年第4期10卷 779-784页

作者： ZHANG Ren-jun 1.2 1. institute of Mountain Hazards and Environment, {1., Chengdu 61.041. Sichuan, china 2. Graduated School of the {1., Beijing 1.0039, china chinese academy of sciences Institute of Mountain Hazards and Environment Chengdu Sichuan China (GRID:grid.9227.e) (ISNI:***) Graduated School of the chinese academy of sciences Beijing China (GRID:grid.9227.e) (ISNI:***)

Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (Geographic Information System) to manage the spatial data,and Multi-Agent systemto simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such aslocation, cost, and state can be analyzed and predicted. Based on this analysis and prediction, themodel of assessing the carrying capacity of resorts is built. Our results show that TSBS will be aneffective tool to accurately assess the carrying capacity of tourist resorts.

关键词： tourist resort carrying capacity TSBS GIS Multi-Agent simulator

BRST quantization and canonical Ward identity of the supersymmetric electromagnetic interaction system

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Science china({1.,Mechanics & Astronomy) 2007年第3期50卷 339-347页

作者： HUANG YongChang1.3,4, JIANG YunGuo1.& LI XinGuo2,3 1.institute of Theoretical {1., College of Applied sciences, Beijing University of Technology, Beijing 1.0022, china 2 institute of Modern {1., chinese academy of sciences, Lanzhou 730000, china 3 Center of Theoretical Nuclear {1., National Laboratory of Heavy Ion Collisions, chinese academy of sciences, Lanzhou 730000, china 4 china Center of Advanced Science and Technology (World Laboratory), Beijing 1.0080, china 1. institute of Theoretical {1. College of Applied Sciences Beijing University of Technology Beijing 100022 China 3. Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Collisions Chinese Academy of Sciences Lanzhou 730000 China 4. china Center of Advanced Science and Technology (World Laboratory) Beijing 100080 China 2. institute of Modern {1. Chinese Academy of Sciences Lanzhou 730000 China

According to the method of path integral quantization for the canonical constrained system in Becchi-Rouet-Stora-Tyutin scheme, the supersymmetric electromagnetic interaction system was quantized. Both the Hamiltonian of the supersymmetric electromagnetic interaction system in phase space and the quantization procedure were simplified. The BRST generator was constructed, and the BRST transforma- tions of supersymmetric fields were gotten; the effective action was calculated, and the generating functional for the Green function was achieved; also, the gauge generator was constructed, and the gauge transformation of the system was ob- tained. Finally, the Ward-Takahashi identities based on the canonical Noether theorem were calculated, and two relations between proper vertices and propaga- tors were obtained.

关键词： supersymmetric electromagnetic interaction BRST quantization Ward identity

Algebraically explicit analytical solu-tions for the unsteady non-Newtonian swirling flow in an annular pipe

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Science china({1.,Mechanics & Astronomy) 2006年第4期49卷 396-400页

作者： CAI Ruixian1.& GOU Chenhua1.2 1. institute of Engineering Thermo{1., chinese academy of sciences, Beijing 1.0080, china 2. Graduate School, chinese academy of sciences, Beijing 1.0080, china 1. institute of Engineering Thermo{1. Chinese Academy of Sciences Beijing 100080 China 2. Graduate School Chinese Academy of Sciences Beijing 100080 China

This paper presents two algebraically explicit analytical solutions for the incompressible unsteady rotational flow of Oldroyd-B type in an annular pipe. The first solution is derived with the common method of separation of variables. The second one is deduced with the method of separation of variables with addition developed in recent years. The first analytical solution is of clear physical meaning and both of them are fairly simple and valuable for the newly developing computational fluid dynamics. They can be used as the benchmark solutions to verify the applicability of the existing numerical computational methods and to inspire new differencing schemes, grid generation ways, etc. Moreover, a steady solution for the generalized second grade rheologic fluid flow is also presented. The correctness of these solutions can be easily proven by substituting them into the original governing equation.

关键词： analytical solution, Oldroyd-B type fluid, swirling flow, non-Newtonian.

Persistent anomalous flows over the subtropical western Pacific insummer

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chinese Science Bulletin 1998年第8期43卷 672-675页

作者： ZHUANG Shiyu\+1.and JI Liren\+2 1. National Meteorological Centre, china Meteorological Administration, Beijing 1.0081. china 2. LASG, institute of Atmospheric physics, chinese academy of sciences, Beijing 1.0080, china National Meteorological Ccntre China Meteomlcgical Administration Beijing China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The distribution of global persistent anomalies shows that the subtropical western Pacific is a key region with high_frequency occurrence of persistent anomalies. Analyses of streamfunction anomalies, OLR anomalies etc. suggest that the convective heating related to Indian monsoon might be responsible for the development of WPA. The results of numerical experiment by two linear barotropic models support the observation.

关键词： persistent anomalies subtropical high Indian monsoon anomalous forcing.

Parentage determination of an isolated Yangtze finless porpoise population Neophocaena phocaenoides asiaeorientalis in the Yangtze Tian-e-Zhou Baiji National Natural Reserve based on molecular data

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Progress in Natural Science:Materials International 2005年第2期15卷 54-61页

作者： XIA Junhong 1.2, ZHENG Jinsong 1.2, XU Limei 1.2 and WANG Ding1.(1. institute of Hydrobiology, {1., Wuhan 430072, china 2. Graduate School of the {1., Beijing 1.0039, china) institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. Graduate School of the chinese academy of sciences Beijing 100039 China

Reproductive behaviors are poorly known for the Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis. In this study, the parentage of an isolated Yangtze finless porpoise population inhabiting the Yangtze Tian-e-Zhou Baiji National Natural Reserve is determined by analysis of microsatellite loci and mitochondrial DNA (mtDNA) control region sequences, and the porpoise's reproductive behaviors are studied. Overall 4 full parentage assignments and additional 3 single parentage assignments were determined for the population of 23 individuals. The analysis shows that their estimated reproductive cycle is shorter than that reported previously and there probably exists an overlapping between gestation and lactation period. The study also shows that the female does not show fidelity to a particular male for breeding and vice versa, the oldest males did not monopolize mating and the dominance rank could not be so strict for the porpoise society. Moreover, the porpoise's mating pattern and relatedness among candidate parents are discussed here. These results provide important information for making guidelines of management and conservation for this protected population.

关键词： Yangtze finless porpoise isolated population reproductive behavior parentage

Forecasting the summer rainfall in North china using the year-to-year increment approach

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Science china Earth {1. 2009年第4期52卷 532-539页

作者： FAN Ke1. LIN MeiJing1.2 & GAO YuZhong3 1.Nansen-Zhu International Research Center, institute of Atmospheric {1., chinese academy of sciences, Beijing 1.0029, china 2 Graduate University of the chinese academy of sciences, Beijing 1.0049, china 3 Heilongjiang Meteorological Administration, Harbin 1.0030, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of the chinese academy of sciences Beijing 100049 China Heilongjiang Meteorological Administ

A new approach to forecasting the year-to-year increment of rainfall in North china in July-August (JA) is proposed. DY is defined as the difference of a variable between the current year and the preceding year (year-to-year increment). NR denotes the seasonal mean precipitation rate over North china in JA. After analyzing the atmospheric circulation anomalies associated with the DY of NR, five key predictors for the DY of NR have been identified. The prediction model for the DY of NR is established by using multi-linear regression method and the NR is obtained (the current forecasted DY of NR added to the preceding observed NR). The prediction model shows a high correlation coefficient (0.8) between the simulated and the observed DY of NR throughout period 1.65-1.99, with an average relative root mean square error of 1.% for the percentage of precipitation rate anomaly over North china. The prediction model makes a hindcast for 2000-2007, with an average relative root mean square error of 21. for the percentage of precipitation rate anomaly over North china. The model reproduces the downward trend of the percentage of precipitation rate anomaly over North china during 1.65-2006. Because the current operational prediction models of the summer precipitation have average forecast scores of 60%-70%, it has been more difficult to forecast the summer rainfall over North china. Thus this new approach for predicting the year-to-year increment of the summer precipitation (and hence the summer precipitation itself) has the potential to significantly improve operational forecasting skill for summer precipitation.

关键词： annual increment North china precipitation prediction prediction skill

Forcing mechanism of the Pleistocene east Asian monsoon variations in a phase perspective

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Science china Earth {1. 2005年第10期48卷 1708-1717页

作者： TIAN Jun1.2, WANG Pinxian1. CHENG Xinrong1. WANG Rujian1.& SUN Xiangjun1.3 1. State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, china 2. {1. of Geology and Geophysics, chinese academy of sciences, Beijing 1.0029, china 3. {1. of Botany, chinese academy of sciences, Beijing 1.0093, china State Key Laboratory of Marine Geology Tongji University Shanghai china institute of Geology and Geo{1. chinese academy of sciences Beijing china institute of Botany {1. Beijing china

The deep sea records from the ODP Sites 1.43 and 1.44 in the northern and southern South china Sea (SCS), including foraminiferal δ 1.O and δ 1.C, Opal% and pollen percentage, reveal that the variations of the east Asian monsoon have been closely correlated with the variations of the Earth’s orbital parameters (eccentricity, obliquity and precession) and the global ice volume on orbital scale. All the monsoonal proxies show strong 1.0 ka, 41.ka and 23 ka cycles. Although G. ruber δ 1.C of Site 1.43 is coherent with the ETP (ETP= normalized (eccentricity + obliquity-precession) at eccentricity, obliquity and precession bands, most of the coherent relationship focuses on the precession band, and the other monsoonal proxies are coherent with the ETP only at the precession band, which indicate that precession dominates the Pleistocene tropical climate changes. The phase relationship of the monsoonal proxies with the foraminiferal δ 1.O implies that the global ice volume changes have played a significant role in modulating the east Asian monsoon climate, at least dominating the winter monsoon. This forcing mechanism of the east Asian monsoon is apparently different from that of the Indian ocean mon-soon. The variations of the east Asian monsoon at the precession band, at least that of the winter monsoon, have been controlled not only by the sensible heating but also by the latent heating of the surface water in the South china Sea.

关键词： South china Sea, ODP, east Asian monsoon, orbital forcing, global ice volume.

The dynamical properties of Rydberg hydrogen atom near a metal surface

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Science china({1.,Mechanics & Astronomy) 2005年第6期48卷 667-675页

作者： GE Meihua1. ZHANG Yanhui1. WANG Dehua2, DU Mengli3 & LIN Shenglu1.1. College of physics and Electronics, Shandong Normal University, Jinan 25001., {1. 2. Department of Mathematics and physics, Shandong institute of Architecture and Engineering, Jinan 25001., {1. 3. institute of Theoretical physics, chinese academy of sciences, Beijing 1.0080, {1. 1. College of physics and Electronics Shandong Normal University 250014 Jinan China 2. Department of Mathematics and physics Shandong Institute of Architecture and Engineering 250014 Jinan China 3. institute of Theoretical {1. Chinese Academy of Sciences 100080 Beijing China

The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion clearly. In this paper we choose the atomic principal quantum number as n = 20. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distance d. When d is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system is integrable. When d becomes smaller, there exists a critical value dc. For d > dc, the system is near-integrable and the motion is regular. While chaotic motion appears for d < dc, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the metal surface.

关键词： Rydberg hydrogen atom, van der Waals interaction, Poincaré surface of section, closed orbit theory, chaos.

Special relativity and theory of gravity via maximum symmetry and localization

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Science china Mathematics 2008年第4期51卷 568-603页

作者： GUO HanYing institute of Theoretical {1. chinese academy of sciences Beijing 1.0080 china 1. institute of Theoretical {1. Chinese Academy of Sciences Beijing 100080 China

Like Euclid, Riemann and Lobachevski geometries are on an almost equal footing, based on the principle of relativity of maximum symmetry proposed by Professor Lu Qikeng and the postulate on invariant universal constants c and R, the de Sitter/anti-de Sitter (dS/AdS) special relativity on dS/AdS-space with radius R can be set up on an almost equal footing with Einstein’s special relativity on the Minkowski-space in the case of R→∞.Thus the dS-space is coin-like: a law of inertia in Beltrami atlas with Beltrami time simultaneity for the principle of relativity on one side, and the proper-time simultaneity and a Robertson-Walker-like dS-space with entropy and an accelerated expanding S 3 fitting the cosmological principle on another side.If our universe is asymptotic to the Robertson-Walker-like dS-space of R ? (3/Λ)1.2, it should be slightly closed in O(Λ) with entropy bound S ? 3πc 3 k B /ΛG?. Contrarily, via its asymptotic behavior, it can fix on Beltrami inertial frames without ‘an argument in a circle’ and acts as the origin of inertia.There is a triality of conformal extensions of three kinds of special relativity and their null physics on the projective boundary of a 5-d AdS-space, a null cone modulo projective equivalence [ $ \mathcal{N} $ ] ? ? P (AdS 5). Thus there should be a dS-space on the boundary of S 5 × AdS 5 as a vacuum of supergravity.In the light of Einstein’s ‘Galilean regions’, gravity should be based on the localized principle of relativity of full maximum symmetry with a gauge-like dynamics. Thus, this may lead to the theory of gravity of corresponding local symmetry. A simple model of dS-gravity characterized by a dimensionless constant g ?(ΛG?/3c 3)1.2 ～ 1.?61.shows the features on umbilical manifolds of local dS-invariance. Some gravitational effects out of general relativity may play a role as dark matter.The dark universe and its asymptotic behavior may already indicate that the dS special relativity and dS-gravity be the foundati

关键词： special relativity de Sitter invariance gravity local de Sitter invariance umbilical manifold 83A05 83D05 53A35 53B50