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Chinese Geographical Science 2006年第2期16卷 109-115页

作者： CHEN Bao-ping ZHANG Jian-chun State Key Laboratory of Estuarine and Coastal Research East China Normal Un＆ersity Shanghai 200062 P. R. China Department of Geography Chizhou Teachers College of A nhui Province Chizhou 247000 P. R. China School of Humanities Hangzhou Teachers College Hangzhou 310036 P. R. China

Soil and water loss is now a major environmental problem in many areas of China, especially in the area of the Dabie Mountain, Anhui Province, which results in environmental degradation and does harm to the people＇s life and production there. Based on the observational records from the Dasha River, the authors analyze the character of the variation in flow and sediment in different flood and dry seasons from 1970 to 2000. The result shows that human activities had significantly reduced the sediment discharge and sediment module, and increased the runoff in low-water seasons since the 1980s. The average contribution rate ofhnman activities to decreasing sediment was 65.67%, and at the same period the contribution rate of runoff and rainfall was about 34.33%. Therefore, it is necessary to take the biological and engineering measures to solve the problem of soil and water loss in the Dasha River watershed.

关键词： river flow sediment discharge human activities effect Dasha River southwest of Anhui Province

Dunkl's Theory and Best Approximation by Entire Functions of Exponential Type in L_2-metric with Power Weight

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Acta Mathematica Sinica,English Series 2014年第10期30卷 1748-1762页

作者： Yong ping LIU chun Yuan SONG School of Mathematical Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education

In this paper, we study the sharp Jackson inequality for the best approximation of f ∈L2,k（Rd） by a subspace Ek2（σ）（SEk2（σ））, which is a subspace of entire functions of exponential type （spherical exponential type） at most σ. Here L2,k（Rd） denotes the space of all d-variate functions f endowed with the L2-norm with the weight vk（x）=Пζ∈R＋}（ζ,x）}2k（ζ）,which is defined by a positive subsystem R＋ of a finite root system R Rd and a function k（ζ）：R→R＋ invariant under the reflection group G（R） generated by R. In the case G（R） = Z2d, we get some exact results. Moreover, the deviation of best approximation by the subspace Ek2（σ）（SE2（σ）） of some class of the smooth functions in the space L2,k（Rd） is obtained.

关键词： Reflection group Dunkl transform Bessel function Jackson inequality continuous modulus

Analytical modeling for colloid-facilitated transport of N-member radionuclides chains in the fractured rock

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Nuclear Science and Techniques 2007年第6期18卷 336-343页

作者： TIEN Neng-Chuan JEN chun-ping Energy and Environment Research Laboratories Industrial Technology Research Institute Hsinchu 310 Taiwan Department of Mechanical Engineering National Chung Cheng University Chia Yi 62102 Taiwan

A precious analytical model for N-member radionuclide decay chains has been extended to include the ef- fect of radionuclide sorption with groundwater *** distribution coefficients were employed in the nu- clide decay chain to illustrate the present *** colloid concentration was assumed constant in time and space owing to equilibrium between colloid generation and sedimentation by chemical and/or physical ***- thermore,the diffusion of colloids into the rock matrix was ignored because the diameter of colloid is relatively large and colloids and fracture surfaces are *** results indicated that colloids could facilitate the transport of radionuclides and the large adsorbability of nuclides with colloids enlarged the effect of acceleration by *** influence of colloids on the radionuclide transport was expected to be crucial to the actinides with large adsorbability; however,the present results revealed that the low-adsorbing nuclides whose parent nuclides have large capability of sorption could be also facilitated significantly by colloids ***,the role of colloids played in the transport of the radionuclides decay chain should be assessed carefully in the radioactive waste *** analyti- cal method presented herein is helpful to verify/validate further complex far-field models.

关键词：分析模型放射性核素氮元素同位素

Colloid-facilitated effects on migration of radionuclides in fractured rock with a kinetic solubility-limited dissolution model

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Nuclear Science and Techniques 2010年第6期21卷 339-346页

作者： Jen, chun-ping Tien, Neng-chuan chung Cheng Univ Dept Mech Engn Taipei 62102 Taiwan Ind Technol Res Inst Energy & Environm Res Labs Hsinchu 31040 Taiwan

Nuclides can move with groundwater either as solutes or colloids,where the latter mechanism generally results in much shorter traveling time as the nuclides interact strongly with solid phases,such as *** the performance assessment,it is therefore essential to assess the relative importance of these two transport mechanisms for different *** relative importance of colloids depends on the nature and concentration of the colloids in ***(Pu),neptunium(Np),uranium(U) and americium(Am) are four nuclides of concern for the long-term emplacement of nuclear wastes at potential repository *** four actinides have a high potential for migrating if attached to iron oxide,clay or silica colloids in the *** sorption of the actinides by colloids in the groundwater may facilitate the transport of these nuclides along potential flow *** solubility-limited dissolution model can be used to assess the safety of the release of nuclear waste in geological disposal ***,it has been assumed that the solubility of the waste form is *** a nuclide reaches its solubility limit at an inner location near the waste form,it is unlikely that the same nuclide will reach its solubility limit at an outer location unless this nuclide has a parent *** is unlikely that the daughter nuclides will exceed their solubility limit due to decay of their parent *** present study investigates the effect of colloids on the transport of solubility-limited nuclides under the kinetic solubility-limited dissolution(KSLD) boundary condition in fractured *** release rate of the nuclides is proportional to the difference between the saturation concentration and the inlet aqueous concentration of the *** presence of colloids decreases the aqueous concentration of nuclides and,thus,increases the release flux of nuclides from the waste form.

关键词：核素迁移胶体浓度溶解度动力学裂隙岩体模型地下水溶质锕系元素

Boundary value problems for two types of degenerate elliptic systems in R^4

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Applied Mathematics(A Journal of Chinese Universities) 2016年第4期31卷 469-480页

作者： WANG Li-ping WEN guo-chun School of Mathematics and Information Science Hebei Normal University LMAM School of Mathematical Sciences Peking University

Firstly, the Riemann boundary value problem for a kind of degenerate elliptic sys- tem of the first order equations in R4 is proposed. Then, with the help of the one-to-one correspondence between the theory of Clifford valued generalized regular functions and that of the degenerate elliptic system＇s solution, the boundary value problem as stated above is trans- formed into a boundary value problem related to the generalized regular functions in Clifford analysis. Moreover, the solution of the Riemann boundary value problem for the degenerate elliptic system is explicitly described by using a kind of singular integral operator. Finally, the conditions for the existence of solutions of the oblique derivative problem for another kind of degenerate elliptic system of the first order equations in R4 are derived.

关键词： Clifford analysis generalized regular function degenerate elliptic system Riemann boundaryvalue problem oblique derivative problem.

Normal Forms for Periodic Orbits of Real Vector Fields

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Acta Mathematica Sinica,English Series 2008年第5期24卷 797-808页

作者： ping WANG Hao WU Wei gu LI School of Mathematical Sciences Peking University Beijing 100871 P. R. China

We consider normal forms of real vector fields near periodic orbits and provide sufficient conditions for their smooth linearization. In addition, the main results also assert the existence of vertical local foliation... 详细信息

关键词： normal form Homotopy method foliation

Neurotoxicity and Biomarkers of Lead Exposure: a Review

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Chinese Medical Sciences Journal 2013年第3期28卷 178-188页

作者： Kang-sheng Liu Jia-hu Hao Yu Zeng Fan-chun Dai ping-qing gu State Key Laboratory of Reproductive Medicine Department of Clinical Laboratory Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University Department of Maternity and Child Health Care School of Public HealthAnhui Medical University Child Health Care Department Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University Obstetrical Department Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University Department of Epidemiological and Health Statistics School of Public Health of Nanjing Medical University

Appropriate selection and measurement of lead biomarkers of exposure are critically important for health care management purposes,public health decision making,and primary prevention *** is one of the neurotoxicants that seems to be involved in the etiology of *** are generally classified into three groups:biomarkers of exposure,effect,and *** main body compartments that store lead are the blood,soft tissues,and bone;the half-life of lead in these tissues is measured in weeks for blood,months for soft tissues,and years for *** the brain,lead-induced damage in the prefrontal cerebral cortex,hippocampus,and cerebellum can lead to a variety of neurological disorders,such as brain damage,mental retardation,behavioral problems,nerve damage,and possibly Alzheimer’s disease,Parkinson’s disease,and *** paper presents an overview of biomarkers of lead exposure and discusses the neurotoxic effects of lead with regard to children and adults.

关键词： lead poisoning biological monitoring neurotoxicity neurodevelopment

Passive, Stable and Order-Adjustable SBS Q-Switching Fiber Laser

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Chinese Physics Letters 2018年第8期35卷 28-31页

作者： guan Wang Lixin Xu chun gu Department of Optics and Optical Engineering University of Science and Technology of China

We propose a new method to separate different orders of an all-fiber passive Q-switching stimulated Brillouin scattering（SBS） laser. We use two fiber Bragg gratings connected by two circulators for the filtering. We obtain a stabilized pulse laser and measure the pulse width of different orders. The first order of SBS has a central wavelength of 1549.75 nm, an average output power of 9 mW, and a pulse width of 400 ns. The pulse width of SBS is reduced by the higher-order signals with the larger fluctuations.

关键词： SBS Passive Stable and Order-Adjustable SBS Q-Switching Fiber Laser

Subspace identification for continuous-time errors-in-variables model from sampled data

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1177-1186页

作者： ping WU chun-jie YANG Zhi-huan SONG State Key Lab of Industrial Control Technology Zhejiang University Hangzhou 310027 China

We study the subspace identification for the continuous-time errors-in-variables model from sampled ***,the filtering approach is applied to handle the time-derivative problem inherent in continuous-time *** generalized Poisson moment functional is focused.A total least squares equation based on this filtering approach is *** by the idea of discrete-time subspace identification based on principal component analysis,we develop two algorithms to deliver consistent estimates for the continuous-time errors-in-variables model by introducing two different instrumental *** determination and other instrumental variables are *** usefulness of the proposed algorithms is illustrated through numerical simulation.

关键词： System identification Errors-in-variables Continuous-time system Subspace method

Conditional privacy protection authentication scheme based on bilinear pairings for VANET

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The Journal of China Universities of Posts and Telecommunications 2020年第1期27卷 62-71页

作者： Song Cheng gu Xin'an ping Yuan Zhang Yadong School of Computer Science and Technology Henan Polytechnic UniversityJiaozuo 454000China School of Information Engineering Xuchang UniversityXuchang 461000China

To solve the problem of security and efficiency of anonymous authentication in the vehicle Ad-hoc network(VANET), a conditional privacy protection authentication scheme for vehicular networks is proposed based on bilinear pairings. In this scheme, the tamper-proof device in the roadside unit(RSU) is used to complete the message signature and authentication process together with the vehicle, which makes it more secure to communicate between RSU and trusted authority(TA) and faster to update system parameters and revoke the vehicle. And this is also cheaper than installing tamper-proof devices in each vehicle unit. Moreover, the scheme provide provable security proof under random oracle model(ROM), which shows that the proposed scheme can meet the security requirements such as conditional privacy, unforgeability, traceability, etc. And the results of simulation experiment demonstrate that this scheme not only of achieves high efficiency, but also has low message loss rate.

关键词： VANET anonymous authentication bilinear pairings conditional privacy protection