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Risk Analysis on Groundwater Resources Carrying Capacity Based on Blind Number Theory

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Wuhan University Journal of Natural sciences 2007年第4期12卷 669-676页

作者： ZHANG Ji1,2.YU Sujun3.. Key Laboratory of Mountain Hazards and Surface Process,chinese Academy of {2./Institute of Mountain Hazards and Environment,chinese Academy of {2.,Chengdu 610041,Sichuan,china 2. graduate University of the chinese Academy of {2.,beijing 100049,china 3. {12. of Environmental Science and Engineering,Southwest Jiaotong University,Chengdu 610041,Sichuan,china Key Laboratory of Mountain Hazards and Surface Process Chinese Academy ofSciences/Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041Sichuan China

Blind numbers of evaluation indices about groundwater resources carrying capacity are defined from the concomitancy of randomness, fuzziness, grey property and unascertainment of groundwater system. Based on fuzzy theory, a comprehensive evaluation model on groundwater resources carrying capacity is constructed with blind information. Then a risk assessment model of surcharge about groundwater resources carrying capacity is established on blind reliability theory. The probable value ＂＊＂ matrix of fuzzy membership degree about carrying capacity corresponding to each judgment level can be obtained with the aid of blind algorithm as well as the subjective reliability ＂×＂ matrix. And then a graph of ＂groundwater carrying capacity v.s. accumulative reliability＂ can be gained Based on the graph, fuzzy membership degree of groundwater resources carrying capacity to each judgment level under different risk probability can be got. Thus, a comparatively reasonable judgment to groundwater resources carrying capacity might be obtained, with comprehensive analysis to the state of society, economy technology and ecology.

关键词： blind number theory groundwater resources carrying capacity evaluation risk analysis

Debating about the climate warming

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Progress in Natural Science:Materials International 2006年第1期16卷 1-6页

作者： WANG Shaowu1, LUO Yong2. ZHAO Zongci2. DONG Wenje2.and YANG Bao3.(1.Department of Atmospheric sciences, {2. of Physics, Peking University, beijing 100871,{3. 2. Laboratory for Climate Studies,{3. Meteorological Administration, beijing 100081,{3. 3. Institute of Cold and Arid Regions Environmental and Engineering, chinese Academy of sciences, Lanzhou 73.000,{3.) [a] Department of Atmospheric sciences School of Physics Peking University Beijing China [b] Laboratory for Climate Studies China Meterological Administration Beijing China [c] Institute of Cold and Arid Regions Environmental and Engineering Chinese Academy of Sciences Lanzhou China

Debating about the climate warming is reviewed. Discussions have focused on the validity of the temperature reconstruction for the last millennium made by Mann et al. Arguments against and for the reconstruction are introduced. Temperature reconstructions by other authors are examined, including the one carried out by Wang et al. in 1996. It is concluded that: (1) Ability of reproducing temperature variability of time scale less than 10 a is limited, so no sufficient evidence proves that the 1990s was the warmest decade, and 1998 was the warmest year over the last millennium. (2. All of the temperature reconstructions by different authors demonstrate the occurrence of the MWP (Medieval Warm Period) and LIA (Little Ice Age) in low frequency band of temperature variations, though the peak in the MWP and trough in LIA varies from one reconstruction to the others. Therefore, terms of MWP and LIA can be used in studies of climate change. (3. The warming from 1975 to 2.00 was significant, but we do not know if it was the strongest for the last millennium, which needs to be proved by more evidence.

关键词： climate warming MWP LIA the 2.th century.

A Test on Different Types of the Time Curve of Hardness Ratio of Gamma-Ray Bursts based on the Curvature Effect

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chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 451-464页

作者： Lan-Wei Jia National Astronomical Observatories/Yunnan Observatory,chinese Academy of sciences,Kunming 650011,{2. {3. school of chinese Academy of sciences,beijing 100049,{2. National Astronomical Observatories/ Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China and graduate school of {2. Academy of {3. Beijing 100049 China

We analyzed a sample of 66 gamma-ray bursts （GRBs） and statistically confirmed the prediction on the time curve of the hardness ratio of GRBs made by Qin et al. based on the curvature effect. In their analysis, GRB pulses are divided into three types according to the shape of their raw hardness ratio （RHR） time curves, defined as to include the background counts to the signal counts, so as to make use of counts within small time intervals. Of the three types, very hard sources exhibit a perfect pulse-like profile （type 1）, hard bursts possess a pulse-like profile with a dip in the decay phase （type 2., and soft bursts show no pulse-like profile but have only a dipped profile （type 3.. In terms of the conventional hardness ratio, type 3.sources are indeed generally softer than those of type 1 and type 2. in agreement with the prediction. We found that the minimum value of RHR is sensitive in distinguishing the different types. We propose that GRB pulses can be classified according to the minimum value of RHR and that the different type sources may be connected with different strengths of the shock or/and the magnetic field.

关键词： gamma-rays burst -- gamma-rays observations - methods statistical

Synthetic aperture radar tomography sampling criteria and three-dimensional range migration algorithm with elevation digital spotlighting

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Science in china(Series F) 2009年第1期52卷 100-114页

作者： TAN WeiXian1,2.3., HONG Wen1,2. WANG YanPing1,2. LIN Yun1,2.3.& WU YiRong1,2.1 State Key Laboratory of Microwave Imaging Technology, {2. 100190, china 2.Institute of Electronics, chinese Academy of {3., {2. 100190, china 3.graduate school, chinese Academy of {3., {2. 100190, china State Key Laboratory of Microwave Imaging Technology Beijing 100190 China Institute of Electronics Chinese Academy of Sciences Beijing 100190 China graduate school Chinese Academy of Sciences Beijing 100190 China

Based on the general geometric model of multi-baseline Synthetic Aperture Radar Tomography （TomoSAR）, the three-dimensional （3.D） sampling criteria, the analytic expression of the 3.D Point Spread Function （PSF） and the 3.D resolution are derived in the 3.D wavenumber domain in this paper. Considering the relationship between the observation geometry and the size of illuminated scenario, a 3.D Range Migration Algorithm with Elevation Digital Spotlighting （RMA-EDS） is proposed. With this algorithm 3.D images of the area of interest can be directly and accurately reconstructed in the 3.D space avoiding the complex operations of 3.D geometric correction. Finally, theoretical analyses and simulation results are presented to demonstrate the shift-varying property of the 3.D PSF and the spatialvarying property of the 3.D resolution and to demonstrate the validity of the 3.D RMA-EDS.

关键词： synthetic aperture radar tomography (TomoSAR) three-dimensional (3.D) SAR imaging 3.D sampling criteria 3.D resolution,3.D range migration algorithm with elevation digital spotlighting (RMA-EDS)

Twistor bundle theory and its application

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Science china Mathematics 2004年第4期47卷 605-616页

作者： PENG Chia-Kuei & TANG ZizhouDepartment of Mathematics, graduate school of {2. Academy of {3., beijing 10003., china Department of Mathematical {3., Tsinghua University, beijing 100084, china 1. Department of Mathematics Graduate School of Chinese Academy of Sciences 100039 Beijing China 2. Department of Mathematical sciences Tsinghua University 100084 Beijing China

Over an oriented even dimensional Riemannian manifold(M 2. ,ds2.), in terms of the Levi-Civita connection form Ω and the canonical form Θ on the bundle of positive orthonormal frames, we give a detailed description of the twistor bundle Гm = SO(2.)/U(m)? J +(@#@ M,ds2.) →M. The integrability on an almost complex structureJ compatible with the metric and the orientation, is shown to be equivalent to the fact that the corresponding cross section of the twistor bundle is holomorphic with respect toJ and the canonical almost complex structureJ 1 onJ +(M,ds2.), by using moving frame theory. Moreover, for various metrics and a fixed orientation onM, a canonical bundle isomorphism is established. As a consequence, we generalize a celebrated theorem of LeBrun.

关键词： almost complex structure, integrability, twistor bundle.

Improvement of different source function expressions in SWAN model for the Bohai Sea

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Progress in Natural Science:Materials International 2005年第8期15卷 720-724页

作者： YIN Baoshu1*, YANG Dezhou1, SHA Rina 1,2.and CHENG Minghua1(1. Institute of Oceanology, chinese Academy of sciences, Qingdao 2.6071,{2. 2. {3. school of the chinese Academy of sciences, beijing 10003.,{2.) Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China. graduate school of the {2. Academy of {3. Beijing 100039 China

The simulating wave nearshore （SWAN） wave model has been widely used in coastal areas, lakes and estuaries. However, we found a poor agreement between modeling results and measurements in analyzing the chosen four typical cases when we used the default parameters of the source function formulas of the SWAN to make wave simulation for the Bohai Sea. Also, it was found that at the same wind process the simulated results of two wind generation expressions （Komen, Janssen） demonstrated a large difference. Further study showed that the proportionality coefficient α in linear growth term of wave growth source function plays an unperceived role in the process of wave development. Based on experiments and analysis, we thought that the coefficient α should change rather than be a constant. Therefore, the coefficient α changing with the variation of friction velocity U*was introduced into the linear growth term of wave growth source function. Four weather processes were adopted to validate the improvement in the linear growth term. The results from the improved coefficient α agree much better with the measurements than those from the default constant coefficient α. Furthermore, the large differences of results between Komen wind generation expression and Janssen wind generation expression were eliminated. We also experimented with the four weather processes to test the new white-capping mechanisms based on the cumulative steepness method. It was found that the parameters of the new white-capping mechanisms are not suitable for the Bohai Sea, but Alkyon's white-capping mechanisms can be applicable to the Bohai Sea after amendments, demonstrating that this improvement of parameter α can improve the simulated results of the Bohai Sea.

关键词： waves SWAN model wave growth source function new proportionality coefficient formula.

Discovery of submicron diamonds within kimberlite in Liaoning Province, china and its significance

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chinese Science Bulletin 1997年第11期42卷 939-941页

作者： BAO Yanan, T. V. Dubuchick and T. D. Liabchekov1. graduate school in {2., {3. Mining University, {2. 100083. china 2. Moscow Resources Institute of Mineral Materials, Russia 3. Resources Institute of Deposit Geology, Russian Academy of sciences, Russia graduate school in {2. Chinese Mining University Beijing China Moscow Resources Institute of Mineral Materials Russia Resources Institute of Deposit Geology Russian Academy of Sciences Russia

ALTHOUGH a lot of research work on diamond mineralogy has already been done,the formationand development of diamond leave much to be *** have done some researches onthe diamond samples with obvious crystal-growing cha... 详细信息

关键词： submicron diamond lath-shape aggregative parent material.

Cotton pixel identification with CBERS-02.CCD data based on spectral knowledge

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Science china(Technological sciences) 2005年第S2期48卷 129-144页

作者： LI Jing1,2.3. LIU Qinhuo1,3. LIU Qiang1, CHEN Liangfu1, BO Junhua3.& LI Shaokun3.1. State Key Laboratory of Remote Sensing Science, IRSA, chinese Academy of sciences, beijing 100101,{3. 2. graduate University of chinese Academy of sciences, beijing 100049,{3. 3. The Key Oasis Eco-agriculture Laboratory of Xinjiang Production and Construction Corps, Shi Hezi 83.000,{3. 1. State Key Laboratory of Remote Sensing Science IRSA Chinese Academy of Sciences 100101 Beijing China 2. graduate University of chinese Academy of {2. 100049 Beijing China 3. The Key Oasis Eco-agriculture Laboratory of Xinjiang Production and Construction Corps 832000 Shi Hezi China

In this paper the in-situ experiment data are collected from the Spectral Library to estimate the possible values of the primary structural parameters in each cotton growing season by statistics. Based on these values the spectra of the cotton major growing seasons were simulated and analyzed using the canopy reflectance model, SAILH. In this way we also simulated the cotton pixel spectra corresponding to CBERS-02.CCD and took them as the reference spectra for spectra fitting. Then No.143.Regiment of No.8 Agricultural Division of Xinjiang Production and Construction Corps (XPCC) was chosen as the study area, and two spectra fitting methods, Mahalanobis distance and spectra angle, were used to identify cotton pixel from CBERS-02.CCD image of the study area. At last we analyzed the effect of the calibration coefficients error on cotton identifying. The results showed that within 4% error the spectral angle classifier can still have a good performance.

关键词： CBERS-02 cotton pixel identification spectra fitting.

Nonlinear interactions between gravity waves and background winds

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Progress in Natural Science:Materials International 2007年第6期17卷 639-644页

作者： Liu Xiao1,2.and Xu Jiyao1(1. State Key Laboratory for Space Weather, Center for Space Science and Applied Research, chinese Academy of sciences, {2. 100080,{3. 2. graduate University of chinese Academy of sciences, beijing 10003.,{3.) [a]State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China [b]graduate University of chinese Academy of {2. Beijing China

Using the nonlinear propagating gravity waves (GW) model in the two-dimensional compressible atmosphere and the linear GW theory, the process of GW propagation in different background winds, e.g. the direction of the background wind is opposite to (dead wind) or the same as (tail wind) the direction of the horizontal phase velocity of GW, is studied. The results show that the dead wind prolongs the vertical wavelength and accelerates GW propagation. Therefore, GW propagates up to a higher height becomes instable in a short time and eventually induces an inverse jet flow. Then, the vertical wavelength is becoming short due to the nonlinear interactions between GW and the inverse jet flow. The vertical wavelength and group velocity decrease after GW propagates into the tail wind. The initial instable time is delayed. Although most of GW is trapped in the instable region, some of GW propagates above the instable region. Compared with GW propagation in the tail wind, the nonlinear interactions between GW and the dead wind are also strong. In contrast, the linear GW theory predicts that GW can propagate freely in the dead wind. The vertical wavelength simulated by the nonlinear numerical model is different from that predicted by the linear theory greatly after GW propagates into the dead wind.

关键词： gravity waves background winds vertical group velocity vertical wavelength nonlinear interactions.