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International Journal of Sediment Research 2011年第1期26卷 1-14页

The suspended sediment flux field in the Yellow and East china Seas(YECS) displays its seasonal variability.A new method is introduced in this paper to obtain the flux field via retrieval of ocean color remote sensing data,statistical analysis of historical suspended sediment concentration data,and numerical simulation of three-dimensional(3.) flow *** components of the sediment flux field include(i) surface suspended sediment concentration inverted from ocean color remote sensing data;(ii) vertical distribution of suspended sediment concentration obtained by statistical analysis of historical observation data;and(iii) 3. flow field modeled by a numerical *** the improved method,the 3. suspended sediment flux field in the YECS has been *** comparison with the suspended sediment flux field solely based on the numerical simulation of a suspended sediment transport model,the suspended sediment flux field obtained by the improved method is found to be more *** 3. suspended sediment flux field from ocean colour remote sensing and in situ observation are more closer to the ***,by quantitatively analyzing the newly obtained suspended sediment flux field,the quantity of sediment erosion and deposition within the different regions can be *** sediment exchange between the Yellow Sea and the East china Sea can be *** mechanism of suspended sediment transport in the YECS can be better *** particular,it is suggested that the long-term transport of suspended sediment is controlled mainly by the circulation pattern,especially the current in winter.

关键词： Suspended sediment flux field Seasonal variability Yellow and East china Seas Regression equation Numerical simulation

A puzzle of the radio-quiet quasar PG 1407+2.5:Are optical and X-ray emissions produced from a relativistic jet?

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Science china(Physics,Mechanics & Astronomy) 2011年第1期54卷 183-186页

作者： CHEN Liang 1,2.3.& BAI JinMing 1,2.1 National Astronomical Observatories/Yunnan Observatory,chinese Academy of Sciences,Kunming 650011,{3. 2.Key Laboratory for the Structure and Evolution of Celestial Objects,chinese Academy of Sciences,Kunming 650011,{3. 3.graduate University of chinese Academy of Sciences,Beijing 100049,{3. 1. National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China2. Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650011 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

PG 1407+2.5 is a radio quiet quasar that has a relativistic *** this report,we show some peculiar properties of its optical and X-ray emissions,which indicate possible non-thermal origins produced from the *** use a simple synchrotron + synchrotron self Compton (SSC) model to fit the emissions with different ratios of energy densities between the magnetic field and electrons (η≡U B/U e),which predicts a different γ-ray *** First LAT AGN Catalog (1LAC) did not include PG 1407+2.5,which indicates an upper limit of γ-ray *** upper limit constrains the ratio to be unreasonably large (η≥10 4-5).This inversely indicates that the optical and X-ray emissions may not be produced from the beaming *** discuss the physical implications of these results.

关键词： active galactic nuclei jet non-thermal emission PG 1407+2.5

Influence factors of sparse microwave imaging radar system performance:approaches to waveform design and platform motion analysis

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Science china(Information Sciences) 2012年第10期55卷 2301-2317页

作者： ZHANG Zhe 1,2.3.ZHANG BingChen 1,2.JIANG ChengLong 1,2.3.XIANG Yin 1,2.HONG Wen 1,2.& WU YiRong 1,2.1 Science and Technology on Microwave Imaging Laboratory,Beijing 100190,china 2.Institute of Electronics,chinese Academy of Sciences,Beijing 100190,china 3.graduate University,chinese Academy of Sciences,Beijing 100190,china 1. Science and Technology on Microwave Imaging Laboratory Beijing 100190 China 2. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China 3. graduate University Chinese Academy of Sciences Beijing 100190 China

Sparse microwave imaging radar is a newly developed concept of microwave imaging system,which tries to combine the traditional radar imaging system with sparse signal processing theories,achieving the aim of reducing the complexity of microwave imaging systems and enhancing the system *** this paper,we introduce some basic concepts of sparse signal processing theory,and then apply it to the traditional radar imaging system to get the mathematical model of sparse microwave imaging *** analyze the factors that determine the performance of sparse microwave imaging radar,including scene,waveform and *** to the radar model,we analyze how these factors influence the radar system and how to optimize *** results of the sparse microwave imaging radar system are also provided.

关键词： sparse microwave imaging radar synthetic aperture radar compressive sensing Lq regularization waveform design

Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2.3., ZHOU Wancun 1 ,ZHOU Jieming 4 , ZHU Mingcang 3.5 1. Institute of Mountain Hazards and Environment, chinese Academy of Sciences , Chengdu 610041, Sichuan, china 2. {2. University of chinese Academy of Sciences, Beijing 100049, china 3. Sichuan Institute of Land Resource Management, Chengdu 610041, Sichuan , china 4. Department of Resources and Environment Science, Sichuan Normal University , Chengdu 610061, Sichuan, china 5. College of Information Engineering, Chengdu University of Technology, Chengdu 610059, Sichuan, china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China graduate University of chinese Academy of Sciences Beijing China Sichuan Institute of Land Resource Management Chengdu Sichuan China Department of Resources and Environment Science Sichuan Normal University Chengdu Sichuan China College of Information Engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2.02. the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

Characteristics of chlorine isotope distribution and analysis on sylvinite deposit formation based on ancient salt rock in the western Tarim Basin

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Science china Earth Sciences 2005年第11期48卷 1913-1920页

作者： TAN Hongbing1,2. MA Haizhou1, XIAO Yingkai1, WEI Haizhen1,2. ZHANG Xiying1 & MA Wandong1 1. Institute of Salt Lakes, chinese Academy of Sciences, Xining 810008,{3. {2. of the chinese Academy of Sciences, Beijing 10003.,{3. 1. Institute of Salt Lakes Chinese Academy of Sciences 810008 Xining China 2. graduate school of the chinese Academy of Sciences 100039 Beijing China

During formation of the Tarim Basin, there repetitively happened seawater invasion for it was ever connected with wide Paleo-mediterranean Sea. At the same time, for the applica-tion of tectonic and paleoenvironmental condition, the basin deposits many sequences of thick strata of evaporites, especially in its two largest subbasins of Kuqa in the north and Shaqa in the southwest. Therefore, the western Tarim Basin has been considered to be a favorable location to prospect ancient sylvinite deposit. But it is unfortunate that the Br×103.Cl ratio, as a common geochemical index to uncover clues of sylvinite deposit, is almost invalid to indicate the stage of ancient brine condensation for very low content of bromine in salt rock samples (less than 10?6 commonly) in the western Tarim Basin evaporites. Fortunately, we noticed recently that the val-ues of chlorine isotope (δ 3.Cl value) for salt rock samples follow some clear laws from place to place, which in the Shaqa subbasin, all δ 3.Cl values of salt rock samples behaved negatively and on the contrary, they all surprisingly showed positive values in the Kuqa subbasin. Based on conclusions of previous research and referring to the ratios of Br×103.Cl for salt rock or brine samples, we proved that the chlorine isotope (δ 3.Cl) could be used as an effective index to find ancient sylvinite deposit in those evaporites rock basin with low content of Br element back-ground, such as the Tarim Basin. Thus according to the new index of chlorine isotope, we con-clude that the concentration of ancient brines formed ancient salt rocks is much more concen-trated in the Shaqa subbasin than that in the Kuqa subbasin. Particularly, the δ 3.Cl value of salt rock in Kashi depression of the western Shaqa subbasin is greatly negative (

关键词： the Tarim Basin, chlorine isotope, ancient salt rock, ancient sylvinite deposit, deposit stage

Impact Assessment and Protection of Outstanding Landscape Integrity in a Natural Heritage Site:Fairy Valley,Kanas Nature Reserve,Xinjiang,china

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Journal of Mountain Science 2011年第1期8卷 46-52页

作者： HAN Fang1,2.YANG Zhaoping1,LIU Xinyu1,2.DI Feng3.1 Xinjiang Institute of Ecology and Geography,chinese Academy of Sciences,Urumqi 83.011,{3. 2.{2. University of chinese Academy of Sciences,Beijing 100049,{3. 3.Xinjiang Department of Science and Technology,Urumqi 83.011,{3. Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China graduate University of chinese Academy of Sciences Beijing China Xinjiang Department of Science and Technology Urumqi China

The essential purpose of the Convention Concerning the Protection of World Cultural and Natural Heritage is to protect the integrity of heritage *** landscape is the core embodiment of the aesthetic value of a natural heritage *** paper proposes a new assessment method from the point of view of the protection of heritage *** is used to measure the degree of outstanding landscape integrity under the human and natural impact in natural heritage *** paper employ three indices,a visual index of outstanding landscape,a harmony index of the artificial landscape and a disturbance index of damaged landscape,to measure the impact of landscape *** impact assessment model is based on a weighted combination of the three *** study site is the Fairy Valley,Kanas Nature Reserve,Xinjiang Uygur Autonomous Region in northwest *** information employed is derived from field investigation and a Digital Elevation Model(DEM).A comprehensive evaluation of the Fairy valley was undertaken and it was determined that the outstanding landscape values are being *** protection methods are proposed to reduce the adverse effects and maintain landscape quality,thereby providing site managers with suggestions for the protection of natural heritage *** broadly,the paper contributes novel methods of landscape assessment applicable to natural protected areas.

关键词： Landscape integrity Landscape impact assessment Landscape protection Natural heritage site Kanas Nature Reserve Xinjiang

Artificial coordinating field and its application to motion planning of robots in uncertain dynamic environments

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Science china(Technological Sciences) 2004年第5期47卷 577-594页

作者： JING Xingjian1, 2. WANG Yuechao1 & TAN Dalong1 1. Robotics Laboratory, Shenyang Institute of Automation, chinese Academy of Sciences, Shenyang 110016, china {2., chinese Academy of Sciences, Beijing 10003., china Correspondence should be addressed to Jing Xingjian 1. Robotics Laboratory Shenyang Institute of Automation Chinese Academy of Sciences 10016 Shenyang China 2. graduate school Chinese Academy of Sciences 10039 Beijing China

Artificial coordinating fields (ACF) are proposed to deal with the motion planning problems of mobile robots in uncertain dynamic environments. An ACF around an obstacle can generate two orthogonal force vectors to a robot: one is called the coordinating force vector which is purposively designed in this paper, and the other is the repulsive force vector which is the same as that in a conventional artificial potential field. The ACF is designed according to the updated motion purpose and the relative states of the robot with respect to its local environment, and it also satisfies the robot’s dynamic constraints. The direction of the coordinating force can be determiend on line according to an optimal evaluation function. The ACF can effectively remove the local minima, and reduce the oscillation of the planned trajectory between multiple obstacles. Only local knowledge of the environments is needed in the ACF-based motion planning. The properties of the ACF such as controllability, adaptability, safety and reachability are studied and discussed in detail in this paper. Theoretical analysis and simulations are given to illustrate our main results.

关键词： artificial coordinating fields, artificial potential fields, mobile robots, motion planning, uncertain dynamic environments.

Sea level variations in the South china Sea inferred from satellite gravity,altimetry,and oceanographic data

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Science china Earth Sciences 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2.ZHONG Min 1,3.& XU HouZe 1,3.1 State Key Laboratory of Geodesy and Earth’s Dynamics,Institute of Geodesy and Geophysics,chinese Academy of Sciences,Wuhan 43.077,china 2.{2. University of chinese Academy of Sciences,Beijing 100049,china 3.Institute of Geophysics,Huazhong University of Science and Technology,Wuhan 43.074,china 1. State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Institute of Geophysics Huazhong University of Science and Technology Wuhan 430074 China

Sea level variations(SLVs) can be divided into two major components:the steric SLV and the mass-induced *** two components of SLV in the South china Sea(SCS) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced SLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced SLV in the SCS with annual amplitude of 2.7±0.4 cm,which is consistent with the annual amplitude of 2.7±0.3.cm estimated from the steric-corrected *** the inter-annual timescales,the mean SLV in the SCS shows a large oscillation,which is mainly caused by the steric *** trend of mean SLV inferred from altimetry in the SCS is 5.5±0.7 mm/yr for the period of 1993.2.09,which is significantly higher than the global sea level rise rate of 3.3.0.4 mm/yr in the same *** is no obvious trend signal in the mass-induced SLV detected from GRACE that indicates the water exchange between the SCS and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the South china Sea sea level variation

Insulin-sensitizing effects of a novel α-methyl-α-phenoxylpropionate derivative in vitro

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Acta Pharmacologica Sinica 2007年第3期28卷 417-422页

作者： Hao-shu WU~(2.4) Juan-hong YU~(3.4) Ying-yin LI~2.Yu-she YANG~3.Qiao-jun HE~2.Yi-jia LOU~(2.5) Ru-yun JI~3.~2.epartment of Pharmacology and Toxicology,College of Pharmaceutical Sciences,Zhejiang University,Hangzhou 3.0058,china ~3.tate Key Laboratory of Drug Research,Shanghai Institute of Materia Medica,Shanghai Institutes for Biological Sciences,graduate {2. of the chinese Academy of Sciences,Shanghai 2.12.3.china Department of Pharmacology and Toxicology College of Pharmaceutical Sciences Zhejiang University Hangzhou 310058 China Department of State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Graduate School of the Chinese Academy of Sciences Shanghai 201203 China

Aim:To examine the insulin sensitizing effects of a novel α-methyl-α-phenoxylpropionate derivative YY2. in insulin-sensitive cell ***:Theperoxisome proliferator-activated receptor γ（PPARγ）agonist bioactivities of YY2.were detected by a preadipocyte differentiation ***-PCR and Westernblotting analysis were used to detect the expression of the target gene or *** effects of YY2. on insulin-mediated glucose consumption were determined inthe HepG2.human hepatocellular carcinoma ***:YY2. could enhancethe differentiation of preadipocytes to adipocytes and upregulate the gene ex-pression of PPARγ2.as well as the protein expression of insulin receptor sub-strate-1（IRS-1）,glucose transporter-4（GLUT4）,and adiponectin（ACRP3.）.Theeffects on GLUT4 and ACRP3. could be reversed by the PPARγ inhibitor ***,YY2. efficiently reduced glucose consumptions in HepG2.cells after2. h culture,and the effects were related to insulin and YY2. ***:YY2.,a potential insulin-sensitizing agent like rosiglitazone,couldenhance glucose consumption in HepG2.cells in a concentration-and insulin-dependent *** may improve the insulin resistance associated with type 2.iabetes.

关键词： YY2. peroxisome proliferator-activated receptor y insulin sensitivity glucose consumption

Power functions with low uniformity on odd characteristic finite fields

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Science china Mathematics 2010年第8期53卷 1931-1940页

作者： ZHA ZhengBang 1,3.& WANG XueLi 2.1 school of Mathematical Sciences,Luoyang Normal University,Luoyang 47102.,{3. 2.school of Mathematical Sciences,South china Normal University,Guangzhou 51063.,{3. 3.State Key Laboratory of Information Security,graduate University of chinese Academy of Sciences,Beijing 100049,{3. 1. school of Mathematical Sciences Luoyang Normal University Luoyang 471022 China3. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China2. School of Mathematical Sciences South China Normal University Guangzhou 510631 China

In this paper,we give some new low differential uniformity of some power functions defined on finite fields with odd *** corollaries of the uniformity,we obtain two families of almost perfect nonlinear functions in GF... 详细信息

关键词： almost perfect nonlinear function differential uniform function finite field