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Complex Behaviors of a Simple Traffic Model

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Communications in Theoretical Physics 2006年第5X期46卷 952-960页

作者： gao xing-Ru Department of Physics and Institute of Theoretical Physics Beijing Normal University Beijing 100875 China Fundamental Teaching Department Beijing Union University Beijing 100101 China

In this paper, we propose a modified traffic model in which a single car moves through a sequence of traffic lights controlled by a step function instead of a sine function. In contrast to the previous work [Phys. Rev. E 70 （2004） 016107], we have investigated in detail the dependence of the behavior on four parameters, ω,α,η and α1, and given three kinds of bifurcation diagrams, which show three kinds of complex behaviors. We have found that in this model there are chaotic and complex periodic motions, as well as special singularities. We have also analyzed the characteristic of the complex period motion and the essential feature of the singularity.

关键词： traffic model complex behavior chaos bifurcation diagram singularity

Human exploitation of carnivores in Pleistocene China: A case study of the faunal remains from Shuidonggou Locality 7

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Science China Earth Sciences 2020年第1期63卷 132-144页

作者： Shuangquan ZHANG Yue ZHANG Shuwen PEI xing gao Key Laboratory for Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China University of Chinese Academy of Sciences Beijing 100049China

Hominin-animal interactions at Pleistocene archaeological sites have been the main subject of research during human evolution. However, in contrast to that of ungulates, little is known about the evidence of human processing of carnivore species in this time interval of China. In this paper, we present the first case report of an interactive relationship between carnivore species and hunter-gathers in Pleistocene China, based mainly on a detailed taphonomic study of the faunal remains from Shuidonggou Locality 7. It seems highly probable that hominins butchered some individuals of carnivores and roasted bone elements with adhering meat at the site;whereas it’s equally feasible that these animals were exploited by hominins mainly for their pelt or fur. In either way, evidence from the site indicates novel strategies in adaptive behaviors adopted by Late Pleistocene foragers in harsh environments of Northwest China.

关键词： Shuidonggou locality 7(SDG7) Upper Palaeolithic Cut marks Burned bones Taphonomy Northwest China

Strong Convergence Theorems of Common Elements for Equilibrium Problems and Fixed Point Problems in Banach Spaces

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Acta Mathematicae Applicatae Sinica 2012年第2期28卷 337-350页

作者： xing-hui gao Hai-yun ZHOU College of Mathematics and Computer Science Yanan UniversityYanan 716000China Department of Mathematics Shijiazhuang Mechanical Engineering UniversityShijiazhuang 050003China

In this paper, we consider hybrid algorithms for finding common elements of the set of common fixed points of two families quasi-C-non-expansive mappings and the set of solutions of an equilibrium problem. We establish strong convergence theorems of common elements in uniformly smooth and strictly convex Banach spaces with the property （K）.

关键词： strong convergence projection quasi-Ф-nonexpansive mapping common elements theproperty (K)

Mechanism and microstructure of Eu(Ⅲ) interaction with γ-MnOOH by a combination of batch and high resolution EXAFS investigation

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Science China Chemistry 2013年第11期56卷 1658-1666页

作者： gao xing SHENG GuoDong HUANG YuYing Shanghai Synchrotron Radiation Facility (SSRF) Shanghai Institute of Applied PhysicsChinese Academy of Sciences School of Chemistry and Chemical Engineering Shaoxing University

In this paper, the macroscopic interaction method and high resolution EXAFS technique with a bent crystal analyzer were combined to study Eu（III） interaction mechanism and microstructure with y-MnOOH as a function of pH. The results indicated that Eu（III） interaction with y-MnOOH was apparently dependent on pH but independent of ionic strength, suggesting the for- mation of inner-sphere surface complexation for Eu（III） onto y-MnOOH. Results of EXAFS analysis indicated that Eu was surrounded by -9.00 atoms in first coordination shell at REu-O =2.40A, and second shell of Mn atoms at REu-Mn ≈ 3.60 was observed for the three adsorption samples. These findings suggested formation of a bidentate surface complex with Eu（III） bonding by edge sharing to MnO6-octahedron on y-MnOOH surface. Both the macroscopic interaction data and the molecular level evidence of Eu（III） microstructure at the 3,-MnOOH-water interface should be factored into better understanding the fate and mobility of Eu（III） and related radionuclides in the natural soil and water environment.

关键词： high resolution EXAFS technique bent crystal analyzer Eu(III) y-MnOOH interaction mechanism microstructure

The first ground tooth artifact in Upper Palaeolithic China

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Science China Earth Sciences 2019年第2期62卷 403-411页

作者： Yue ZHANG Shuangquan ZHANG xing gao Fuyou CHEN Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences CAS Center for Excellence in Life and Paleoenvironment University of Chinese Academy of Sciences

Scholars have long recognized the importance of organic artifacts to an improved understanding of the economic and social behavior of Palaeolithic hominins. However, in contrast to archaeological studies in other parts of the world, osseous industries from China have received only limited attention. As one of the first steps aiming at tipping this balance, the current paper examines, therefore, a shaped boar tusk—one particular element of hunter-gatherers’ tool kit at Shuidonggou Locality 12 (SDG12). Morphological and metrical comparisons of the tusk with both paleontological specimens and bone artifacts from the same site demonstrate that wear pattern on one of the dentin surfaces of the tooth is not significant different from occlusal attritions in living animals, while linear striations on the other dentin facet are most probably artificial grinding marks formed by prehistoric toolmakers in attempts to manufacture a scraper. The tusk specimen from SDG12 represents the first evidence of a ground tooth in Upper Palaeolithic China. The current study indicates that hominins in Shuidonggou area had achieved a deepened understanding of physical properties of osseous material available in environs and ultimately broadened their range of raw material selection by adding a particular element to the inventory of subsistence tools.

关键词： Upper Palaeolithic Osseous artifacts Boar tusk Grinding Splitting Shuidonggou

New progress in understanding the origins of modern humans in China

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Science China Earth Sciences 2017年第12期60卷 2160-2170页

作者： gao xing PENG Fei FU QiaoMei LI Feng Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044 University of the Chinese Academy of Sciences Beijing 100049China Department of Early Prehistory and Quaternary Ecology University of TubingenTubingen 72070Germany

Hypotheses concerning the origins of modern humans have been intensively debated, and two competing models, the recent "Out-of-Africa" and "Multiregional Evolution" paradigms, have dominated research and discussions for decades. Evidence from China has played a fundamental role in this debate: regional continuity and replacement by populations in-migrated from Africa have both been suggested and supported mainly by paleoanthropologists and geneticists, respectively. As more evidence has accumulated, new results obtained, and more scholars from various disciplines become involved, supporters of the recent "Out-of-Africa" model agree more or less with the "Multiregional Evolution" model regarding the complex history of modern humans and their interbreeding with other archaic populations(e.g., Neandertals). Recent discoveries of new human fossils, Paleolithic archaeological materials, and ancient DNA evidence in China have yielded a large body of information regarding the formation and development of modern humans in this region. However, controversies continue, including that most molecular biologists insist on the replacement of archaic populations by modern humans dispersed from Africa, while most paleoanthropologists and archaeologists propose an enhanced "Continuity with Hybridization" model. In this paper, we compile new results and progress in China and present the current debates and issues on the origins of modern humans. Finally, we offer several suggestions for future studies.

关键词： China Origins of modern humans Modern behavior Recent out-of-Africa Continuity with hybridization Interdisciplinary research

Technology diffusion and population migration reflected in blade technologies in northern China in the Late Pleistocene

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Science China Earth Sciences 2016年第8期59卷 1540-1553页

作者： LI Feng CHEN FuYou WANG YingHua gao xing Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Inner Mongolia Museum Hohhot 010010 China

In recent years, the origin and evolution of modern human behaviors have become a common topic of research in Paleolithic archaeology. One important part of modern human behavior, blade technology, was once thought to be unique to modern humans. Recent studies have suggested that variations in blade technology do not fully correspond to modern populations. However, the standardization, diversity, discontinuity in terms of time distribution, and differences in spatial distribution of blade technology give it an important role in discussions of modes of adaptation, diffusion of technology, and population migration of hominins. By categorizing the major blade assemblages in China, we show that there were two blade reduction methods in northern China: the Levallois method and the prismatic method. Dating back 40000–30000 years, the Levallois and prismatic blade method combined to form the characteristics of the early stage of the Upper Paleolithic. Artifacts bearing such characteristics are located in Northwest China, Northeast China, and the Qinghai-Tibet Plateau. The unearthed blades are similar in technological organization and are connected geographically with those discovered in Siberia and Mongolia, which also indicates a distinct border from those discovered in northern China. This fact is suggestive of population immigration. About 29000–25000 years ago, a combination of prismatic blades and microblades was developed in the hinterland of China; however whether it can be regarded as the representative of population migration or only a technological adaption remains undetermined. We suggest that the system of production of different blades should be distinguished in the study of blade assemblages and that different blade methods should not be integrated into a single technical system to discuss technology diffusion and population dispersal.

关键词： North China Late Pleistocene Blade technology Technology diffusion Human migration

The first photometric analysis of the totally eclipsing contact binary V811 Cep

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Research in Astronomy and Astrophysics 2021年第8期21卷 99-105页

作者： Xiang gao Kai Li xing gao Yuan Liu Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China Xinjiang Astronomical Observatory Urumqi 830011China Qilu Institute of Technology Jinan 250200China

The first photometric analysis of V811 Cep was carried *** first complete light curves of V,R and I bands are *** analysis was carried out by the Wilson-Devinney(W-D)program,and the results show that V811 Cep is a median-contact binary(f=33.9(±4.9)%)with a mass ratio of *** is a W-subtype contact binary,that is,the component with less mass is hotter than the component with more mass,and the light curves are asymmetric(O’Connell effect),which can be explained by the existence of a hot spot on the component with less *** orbital inclination is i=88.3°,indicating that it is a totally eclipsing binary,so the parameters obtained are *** the O-C analyzing,it is found that the orbital period decreases at the rate of P=-3.90(±0.06)×10^(-7)d yr^(-1),which indicates that the mass transfer occurs from the more massive component to the less massive one.

关键词： binaries:close binaries:eclipsing stars:evolution stars:individual(V811 Cep)

Nickel-Catalyzed Difluoroalkylation of （Hetero）aryl Bromides with Unac-tivated 1-Bromo-l,l-difluoroalkanes

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Chinese Journal of Chemistry 2018年第11期36卷 1059-1062页

作者： Xu He xing gao xingang Zhang Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China

Although extensive efforts on fluoroalkylations have been made over the past decade, new and efficient methods to incorporate fluorinated groups into organic molecules remain highly desirable. Herein, we report an efficient method for catalytic synthesis of difluoroalkylated (hetero)arenes through nickel‐catalyzed reaction between readily accessible (hetero)aryl bromides and unactivated 1‐bromo‐1,1‐difluoroalkanes. The reaction exhibits high functional group tolerance and broad substrate scope, providing a cost‐efficient and straightforward route for applications in medicinal chemistry.

关键词： arylbromides 1‐bromo‐1 1‐difluoroalkanes cross‐coupling difluoroalkylations fluorine nickel