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A new notion of soundness in bare public-key model

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Progress in Natural Science:Materials International 2003年第12期 47-51页

作者： ZHAO Yunlei 1,2. * and ZHU hong 1(1. department of Computer Science, Fudan {2., Shanghai 2.0433, China 2. department of Computer Science, city university of hong kong, hong kong, China) department of Computer Science，Fudan university，Shanghai 2.0433，China department of Computer Science，city university of hong kong，{2.，China department of Computer Science，Fudan university，Shanghai 2.0433，China

A new notion of soundness in bare public key (BPK) model is presented. This new notion just lies in between one time soundness and sequential soundness and its reasonableness is justified in the context of resettabl... 详细信息

关键词： bare public key model resettable zero knowledge pseudorandom functions complexity leveraging.

Assessment of biochemical concentrations of vegetation using remote sensing technology

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Journal of Geographical Sciences 2002年第3期12卷 321-330页

作者： DING Shengyan, GU Jidong, QIAN Lexiang(1. College of Environment and Planning, Henan university, Kaifeng 475001, China 2. department of Ecology & Biodiversity, The university of hong kong, hong kong, China) College of Environment and Planning Henan University Kaifeng 475001 department of Ecology & Biodiversity The University of Hong Kong 香港

The main biochemicals (such as lignin, protein, cellulose, sugar, starch, chlorophyll and water) of vegetation are directly or indirectly involved in major ecological processes, such as the functions of terrestrial ecosystems (i.e., nutrient-cycling processes, primary production, and decomposition). Remote sensing techniques provide a very convenient way of data acquisition capable of covering a large area several times during one season, so it can play a unique and essential role provided that we can relate remote sensing measurements to the biochemical characteristics of the Earth surface in a reliable and operational way. The application of remote sensing techniques for the estimation of canopy biochemicals was reviewed. Three methods of estimating biochemical concentrations of vegetation were included in this paper: index, stepwise multiple linear regression, and stepwise multiple linear regression based on a model of the forest crown. In addition, the vitality and potential applying value are stress

关键词： biochemicals vegetation remote sensing techniques

基于多光谱图像角度融合测定库尔勒香梨理化指标

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光谱学与光谱分析 2024年第3期44卷 649-655页

作者：刘鸿阳孔德国罗华平高峰王聪颖塔里木大学机械电气化工程学院新疆阿拉尔843300 自治区教育厅普通高等学校现代农业工程重点实验室新疆阿拉尔843300

基于多光谱图像角度融合,提出了一种库尔勒香梨快速无损检测的方法。以库尔勒香梨为研究对象,应用多光谱成像采集系统,以10°为间隔,获取了相对方位角为10°~90°内的多光谱图像。使用ENVI5.1软件进行多光谱图像角度融合并提取感兴趣区... 详细信息

基于多光谱图像角度融合,提出了一种库尔勒香梨快速无损检测的方法。以库尔勒香梨为研究对象,应用多光谱成像采集系统,以10°为间隔,获取了相对方位角为10°~90°内的多光谱图像。使用ENVI5.1软件进行多光谱图像角度融合并提取感兴趣区域(ROI),获得多光谱数据。对光谱反射率、波段和相对方位角进行了皮尔逊相关性分析,发现波段和相对方位角都对光谱反射率呈极显著相关性,且相对方位角相关系数为0.1大于波段相关系数0.053,有必要在建模过程中加入相对方位角因素。采用标准正态变量变换(SNV)、均值中心化变换(MC)、卷积平滑处理(S_G)和归一化处理(Nor)等预处理方法,选用偏最小二乘回归(PLSR)建立全波段检测模型,通过校正集相关系数(R_(c))、预测集相关系数(R_(p))、校正集均方根误差(RMSEC)和预测集均方根误差(RMSEP)对模型的效果进行评价,对比探究特征角度下和角度融合下库尔勒香梨关键指标的模型检测效果。结果表明:采用角度融合处理后,所建立的PLSR和SVM模型预测效果都有显著提升。预测库尔勒香梨含水率最优模型为采用角度融合的偏最小二乘回归模型(AF-PLSR),其R_(c)为0.936, RMSEC为0.2.8,R_(p)为0.901, RMSEP为0.2.5;预测库尔勒香梨硬度和糖度的最优模型为以角度融合的支持向量机模型(AF-SVM),R_(c)分别为0.894、 0.905, RMSEC为0.52.、 0.376;R_(p)为0.830、 0.901, RMSEP为0.532. 0.379。角度融合将不同角度下的光谱数据结合在一起,获得了比单一角度更加丰富的信息,得到了更加完善的光谱。所建立的检测模型精度更高。结果证明:基于多光谱图像角度融合技术预测库尔勒香梨的含水率、硬度和糖度是可行的。为提高多光谱无损检测精度和高光谱无损检测精度提供了一种新的思路。

关键词：多光谱成像融合光谱库尔勒香梨偏最小二乘回归

TAX EVASION:MODELS WITH SELF-AUDIT

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Journal of Systems Science & Complexity 2008年第4期21卷 487-518页

作者： Kin Keung LAI department of Management Sciences City University of Hong Kong College of Business Management Hunan University

Different from traditional tax audit, supervision with self-audit is a combination of audit by the taxpayer himself and audit by the tax authority. This paper mainly studies a taxpayer＇s optimal policy of tax evasion under supervision with self-audit and its related properties, in order to deduce some effective suggestions and theoretical bases to restrain tax evasion. Assuming that only a certain proportion of evaded tax can be discovered when the audit is executed, the authors first formulate a static model with self-audit. This model is divided into two stages. At the first stage, taxpayers declare their taxes, then the tax authority chooses audit objects, based on a known probability, and announces the result; if the taxpayer is chosen, he will enter the second stage, during which he has a chance to pay the evaded tax and the corresponding late fees and then is audited by the tax authority. The authors show the existence and uniqueness of the optimal amount of tax evasion at the first stage and the optimal proportion to self-expose at the second stage. The authors also discuss the related properties of the interior solution, and do elasticity analyses on some parameters. Besides, the authors extend the static model into the corresponding two-period model, and study the existence and uniqueness of the solution of the extended model. Finally, under the assumption that tax evasion can only be discovered with a certain probability when the audit is executed, the authors formulate another static model with self-audit and investigate its properties.

关键词： Existence and uniqueness of the solution self-audit static model tax evasion two-period model.

Finite element analysis for general elastic multi-structures

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Science China mathematics 2006年第1期49卷 109-129页

作者： HUANG Jianguo, SHI Zhongci & XU Yifeng department of {2., Shanghai Jiao long university, Shanghai 2.02.0, China Division of Computational Science, E-lnstitute of Shanghai Universities, Shanghai Normal university, Shanghai 2.02.4, China Institute of Computational {2., Academy of {2. and Systems Science, Chinese Academy of Sciences, Beijing 100080, China department of {2., Chinese university of hong kong, Shatin, N. T., hong kong, China department of mathematics Shanghai Jiao Tong University Shanghai 200240 China Division of Computational Science E-Institute of Shanghai Universities Shanghai Normal University Shanghai 200234 China Institute of Computational mathematics Academy of Mathematics Systems Science Chinese Academy of Sciences Beijing 100080 China department of mathematics Chinese University of Hong Kong Shatin N. T. Hong Kong China

A finite element method is introduced to solve the general elastic multi-structure problem, in which the displacements on bodies, the longitudinal displacements on plates and the longitudinal displacements on beams are discretized using conforming linear elements, the rotational angles on beams are discretized using conforming elements of second order, the transverse displacements on plates and beams are discretized by the Morley elements and the Hermite elements of third order, respectively. The generalized Korn's inequality is established on related nonconforming element spaces, which implies the unique solvability of the finite element method. Finally, the optimal error estimate in the energy norm is derived for the method.

关键词： elastic multi-structures, finite elements, generalized Korn's inequality, unique solvability, error estimates.

Surface Microstructure Characterization of Sol-gel Derived Porous TiO_2.Thin Films

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Rare Metals 2001年第3期20卷 157-163页

作者： Jiaguo Yu, Jimmy C. Yu, Bei Cheng, A. S. K. Li, Pak Kan Tse 1) department of Chemistry, The Chinese university of {2., {2., China 2. State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan university of Technology, W Chinese Univ hong kong Dept Chem Hong Kong Hong Kong Peoples R China Wuhan Univ Technol State Key Lab Adv Technol Mat Synth & Proc Wuhan 430070 Peoples R China Chinese Univ hong kong Dept Phys Hong Kong Hong Kong Peoples R China

Porous TiO2.thin films were prepared from alkoxide solutions with and without polyethylene glycol (PEG) by sol-get route on soda lime glass, and were characterized by atomic force microscopy (AFM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The results show that TiO2.film prepared from precursor solution without PEG is composed of spherical particles of about 100 nm and several nanometer mesoporous pores. With the increase of the amount of PEG added to the precursor solution, the diameter and the depth of the pores in the resultant films increas on the decomposition of PEG during heat-treatment, which lead to them increase of the surface roughness of the films. XRD and TEM results show that the single anatase phase is precipitated and there are some orientation effects in (101) direction.

关键词： sol-gel route porous TiO2.thin films surface microstructure characterization

Convergence Rate to Stationary Solutions for Boltzmann Equation with External Force

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Chinese Annals of mathematics,Series B 2006年第4期27卷 363-378页

作者： Seiji UKAI Tong YANG Huijiang ZHAO department of Applied -mathematics Yokohama National University 79-5 Tokiwadai Hodogaya-ku Yokohama 240-8501 Japan. department of mathematics City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong China. School of mathematics and Statistics Wuhan University Wuhan 430072 China.

For the Boltzmann equation with an external force in the form of the gradient of a potential function in space variable, the stability of its stationary solutions as local Maxwellians was studied by S. Ukai et al. （2.05） through the energy method. Based on this stability analysis and some techniques on analyzing the convergence rates to stationary solutions for the compressible Navier-Stokes equations, in this paper, we study the convergence rate to the above stationary solutions for the Boltzmann equation which is a fundamental equation in statistical physics for non-equilibrium rarefied gas. By combining the dissipation from the viscosity and heat conductivity on the fluid components and the dissipation on the non-fluid component through the celebrated H-theorem, a convergence rate of the same order as the one for the compressible Navier-Stokes is obtained by constructing some energy functionals.

关键词： Convergence rate Boltzmann equation with external force Energy functionals Stationary solutions

Synthesis and optical limiting in copolymers of C_(60) and 1-phenyl-1-butyne

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Chinese Chemical Letters 2000年第1期11卷 21-22页

作者： hong Yao XU Shan Yi GUANG Ben Zhong TANG ({2. of Chemistry, Anhui university, Hefei 2.0039 {2. of Chemistry, hong kong university of Science & Technology, Clear Water Bay, Kowloon, hong kong) Anhui Univ Dept Chem Hefei 230039 Peoples R China hong kong Univ Sci & Technol Dept Chem Kowloon Peoples R China

While WC_16-Ph_4Sn is a poor catalyst for the polymerization of l-phenyl-butyne (PB) at room temperature, it effectively polymerizes PB in the presence of C_(60), giving high molecular weight polymers in high yields. The polymer is soluble in THF and chloroform and spectroscopic analysis reveals that Coo has copolymerized with PB. Thus, C_(60) plays dual roles of comonomer and cocatalyst in the acetylene polymerization. The copolymers strongly attenuate 532.nm laser pulses, whose limiting performance is superior to that of parent C_(60)

关键词： C_(60) polyacetylene fullerene polymer.

The Response of Carbonate System to Watershed Urbanization Process in a Semi-Arid River

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Journal of Ocean university of China 2024年第4期23卷 991-1002页

作者： LI Yunxiao DANG Jiajia HUANG Xiao YANG hong WANG Xiao LI Lina BAI Jie CHEN Xi department of Environmental Science College of Resource and EnvironmentShanxi Agricultural UniversityTaigu 030801China Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China department of Geography and Environmental Science University of ReadingWhiteknightsReading RG66ABUK Marine Agriculture Research Center Tobacco Research InstituteChinese Academy of Agricultural SciencesQingdao 266101China 5 Key Laboratory of Marine Environmental Science and Ecology Ministry of EducationCollege of Environmental Science and EngineeringOcean University of ChinaQingdao 266100China

Different from rivers in humid areas,the variability of riverine CO_(2. system in arid areas is heavily impacted by anthropogenic disturbance with the increasing urbanization and water *** this study,the water chemistry and the controls of carbonate system in an urbanized river(the Fenhe River)on the semi-arid Loess Plateau were *** water chemistry of the river water showed that the high dissolved inorganic carbon(DIC)concentration(about 37 mg L^(-1))in the upstream with a karst land type was mainly sourced from carbonate weathering involved by H_(2.CO_(3) and H_(2.SO_(4),resulting in an oversaturated partial pressure of CO_(2.(pCO_(2.)(about 800μatm).In comparison,damming resulted in the widespread appearance of non-free flowing river segments,and aquatic photosynthesis dominated the DIC and pCO_(2. spatiality demonstrated by the enriched stable isotope of DIC(δ^(13)CDIC).Especially in the mid-downstream flowing through major cities in warm and low-runoff August,some river segments even acted as an atmospheric CO_(2. *** noteworthy is wastewater input leading to a sudden increase in DIC(>55 mg L^(-1))and pCO_(2.(>4500μatm)in the downstream of Taiyuan city,and in cold November the increased DIC even extended to the outlet of the *** results highlight the effects of aquatic production induced by damming and urban sewage input on riverine CO_(2. system in semi-arid areas,and reducing sewage discharge may mitigate CO_(2. emission from the rivers.

关键词： dissolved inorganic carbon stable carbon isotope carbonate weathering aquatic photosynthesis sewage input the Fenhe River