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Characteristics of the Lower Yellow River channel shrinkage and its discriminant parameters

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Science china(Technological Sciences) 2010年第5期53卷 1374-1386页

作者： HU ChunHong1 & ZHANG GuoGang2 1 china institute of Water Resources and Hydropower Research,Beijing 100038,china 2 Guangdong Electric Power Design institute,Guangzhou 510663,china china institute of Water Resources and Hydropower Research Guangdong Electric Power Design institute

This paper analyzes the changing trends of the Lower Yellow River(LYR) transverse profile parameters and their aberrance points by the time series analysis *** results show that there has been a trend of changes in the LYR channel transverse profile parameters since the *** main river channel has a tendency of shrinkage year by year and the trend will be continued in the *** main features of the LYR channel shrinkage are remarkable reductions of bankfull dis-charges and bankfull areas,corresponding decreases of bankfull widths,average bankfull water depths and maximal bankfull water depths,as well as increases of bankfull water levels and width-depth ratios *** discriminant parameters for threshold of the LYR main channel shrinkage were put *** indicates that the LYR main channel began to shrink in the 1970s and has entered into a serious phase of channel shrinkage since the *** incompatible index of discharged water-sediment processes of the Sanmenxia Reservoir was introduced,which revealed that there was a trend of increasing in the incompatibility between water flow and sediment *** relations between the LYR main channel shrinkage parameters and discharged water-sediment processes of the Sanmenxia Reservoir were founded,which indicate that the LYR main channel shrinkage can be mitigated and improved through the regulation of discharged water-sediment processes of the reservoir,especially through the regulation of water-sediment incompatible *** LYR channel for water and sediment transportation can be restored and maintained.

关键词： Lower Yellow River time series analysis main river channel shrinkage discriminant parameters of channel shrinkage water-sediment incompatible index

Mechanical decision for a class of integral inequalities

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Science china(Information Sciences) 2010年第9期53卷 1800-1815页

作者： YANG Lu1,3,YU WenSheng1,2* & YUAN RuYi2 1Shanghai Key Laboratory of Trustworthy Computing,Software Engineering institute,East china Normal University,Shanghai 200062,china 2the Key Laboratory of Complex Systems and Intelligence Science,institute of Automation,Chinese Academy of Sciences,Beijing 100190,china 3Laboratory for Automated Reasoning and Programming,Chengdu institute of Computer Applications,Chinese Academy of Sciences,Chengdu 610041,china Shanghai Key Laboratory of Trustworthy Computing Software Engineering Institute East China Normal University The Key Laboratory of Complex Systems and Intelligence Science Institute of Automation Chinese Academy of Sciences Laboratory for Automated

A class of integral inequalities is transformed into homogeneous symmetric polynomial inequalities beyond Tarski model,where the number of elements of the polynomial,say n,is also a variable and the coefficients are functions of *** is closely associated with some open problems formulated recently by Yang et *** Timofte's dimension-decreasing method for symmetric polynomial inequalities,combined with the inequality-proving package BOTTEMA and a program of implementing the method known as successive difference substitution,we provide a procedure for deciding the nonnegativity of the corresponding polynomial inequality such that the original integral inequality is mechanically decidable;otherwise,a counterexample will be *** effectiveness of the algorithm is illustrated by some more examples.

关键词： integral inequality symmetric polynomial inequality Timofte’s dimension-decreasing method successive difference substitution mechanical decision inequality-proving package BOTTEMA

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中建滨湖设计总部,成都,四川,中国

世界建筑 2024年第4期 16-19页

作者： china Southwest Architectural Design and Research institute Corp. Ltd. 中国建筑西南设计研究院有限公司

作为西南地区首个近零能耗建筑项目,中建滨湖设计总部从地域气候适应性的节能研究出发,考虑冬夏不同工况,突破体型系数的限制,提出了夏热冬冷地区超低能耗建筑设计的理论及方法。项目综合运用被动式策略、主动式技术与可再生能源,结合... 详细信息

作为西南地区首个近零能耗建筑项目,中建滨湖设计总部从地域气候适应性的节能研究出发,考虑冬夏不同工况,突破体型系数的限制,提出了夏热冬冷地区超低能耗建筑设计的理论及方法。项目综合运用被动式策略、主动式技术与可再生能源,结合工业化技术与新材料研发,最终实现形式空间、建筑技术与能耗性能的良好匹配。

关键词：可再生能源工业化技术体型系数气候适应性新材料研发西南地区

A distributed estimator for on-road target tracking with lane estimation and identification

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Science china(Information Sciences) 2010年第12期53卷 2495-2505页

作者： CHEN YangSheng The Thirty-Eighth Research institute,china electronics Technology Group Corporation,199 Xiangzhang Blvd,Hefei 230088,china The Thirty-Eighth Research institute China Electronics Technology Group Corporation

For ground target tracking with road constraints,the existing methods ignore the road width,which can lead to significant biases of the target state estimates when the road width is *** this paper,based on the proposed novel two-dimensional(2D) road representation which additionally allows to model target lateral motion,a distributed estimator(DE) with lane estimation and identification is *** estimator uses radar and image sensor based local estimates to provide a global estimate of the target displacement from the road *** local estimators,the updated lane estimations are used for *** representative simulation results show that the proposed estimator achieves much better estimation performance than the mileage estimator(ME),and the lane identifier can effectively identify the lane which the target is in.

关键词： on-road target tracking road representation lateral motion interact multi-model(IMM) algo-rithm fusion lane identification

Theoretical study of ZnO adsorption and bonding on Al_2O_3(0001) surface

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Science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 664-675页

作者： LI Yanrong1,YANG Chun1,2,XUE Weidong1,LI Jinshan3 & LIU Yonghua3 1.institute of Microelectronics and Solid State electronics,University of Electronic Science and Technol- ogy of china,Chengdu 610054,china 2.institute of Mathematics and Software Science,Sichuan Normal University,Chengdu 610068,china 3.institute of Chemical Materials,china Academy of Engineering Physics,Mianyang 621000,china institute of Microelectronics and Solid State electronics University of Electronic Science and Technology of China Chengdu 610054 China institute of Mathematics and Software Science Sichuan Normal University Chengdu 610068 China institute of Chemical Materials China Academy of Engineering Physics Mianyang 621000 China

ZnO adsorption on sapphire (0001) surface is theoretically calculated by using a plane wave ultrasoft pseudo-potential method based on ab initio molecular dynamics. The results reveal that the surface relaxation in the first layer Al-O is reduced, even eliminated after the surface adsorption of ZnO, and the chemical bonding energy is 434.3(±38.6) kJ·mol?1. The chemical bond of ZnO (0.185 ± 0.01 nm) has a 30° angle away from the adjacent Al-O bond, and the stable chemical adsorption position of the Zn is deflected from the surface O-hexagonal symmetry with an angle of about 30°. The analysis of the atomic populations, density of state and bonding electronic density before and after the adsorption indicates that the chemical bond formed by the O2 of the ZnO ? and the surface Al3+ has a strong ionic bonding characteristic, while the chemical bond formed by the Zn2+ and the surface O2 has an obvious covalent characteristic, which ? comes mainly from the hybridization of the Zn 4s and the O 2p and partially from that of the Zn 3d and the O 2p.

关键词： α-Al2O3 (0001) ZnO ab initio molecular dynamics chemical adsorption density of states

Report on Cardiovascular Health and Diseases in china 2023:An Updated Summary

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Biomedical and Environmental Sciences 2024年第9期37卷 949-992页

作者： National Center for Cardiovascular Diseases The Writing Committee of the Report on Cardiovascular Health and Diseases in china Shengshou Hu .

Since 1990,china has made considerable progress in resolving the problem of“treatment difficulty”of cardiovascular diseases(CVD).The prevalent unhealthy lifestyle among Chinese residents has exposed a massive proportion of the population to CVD risk factors,and this situation is further worsened due to the accelerated aging population in *** remains one of the greatest threats to the health of Chinese *** terms of the proportions of disease mortality among urban and rural residents in china,CVD has persistently ranked *** 2021,CVD accounted for 48.98%and 47.35%of deaths in rural and urban areas,*** out of every five deaths can be attributed to *** implement a national policy“focusing on the primary health institute and emphasizing prevention”and truly achieve a shift of CVD prevention and treatment from hospitals to communities,the National Center for Cardiovascular Diseases has organized experts from relevant fields across china to compile the“Report on Cardiovascular Health and Diseases in china”annually since *** 2024 report is established based on representative,published,and high-quality big-data research results from cross-sectional and cohort population epidemiological surveys,randomized controlled clinical trials,large sample registry studies,and typical community prevention and treatment cases,along with data from some projects undertaken by the National Center for Cardiovascular *** firsthand data not only enrich the content of the current report but also provide a more timely and comprehensive reflection of the status of CVD prevention and treatment in china.

关键词： Cardiovascular disease Risk factor Prevalence Mortality Rehabilitation Basic research Medical device development Health economics

Constrained Bézier curves' best multi-degree reduction in the L2-norm

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Progress in Natural Science:Materials International 2005年第9期15卷 843-850页

作者： ZHANG Renjiang 1,2 ** and WANG Guojin1(1. institute of Computer Images and Graphics, Zhejiang University, Hangzhou 310027, china 2. china institute of Metrology, Zhejiang, Hangzhou 310034, china) institute of Computer Images and Graphics Zhejiang University Hangzhou 310027 China. State Key Laboratory of CAD&CG Zhejiang University Hangzhou 310027 China. china institute of Metrology Zhejiang Hangzhou 310034 China

In computer aided geometric design, the degree reduction of the parameter curve is a key technique in data exchange and data compression. The various existing methods of degree reduction cannot decide whether the degree reduction curve satisfying the given tolerance exists beforehand, cannot give approximation of the best multi-degree reduction, or cannot provide explicit expression and error formula of the degree reduction curve. In this paper, we propose an entirely new method, which can hurdle the above flaws completely. For a given Bézier curve of degree n, we can easily decide whether a Bézier reduction curve of degree m exists, which has equal derivatives with the given curve up to （r-1）-th and （s-1）-th orders （r,s≤m） respectively at the endpoints, so the approximating error is less than the given tolerance ε in the L2-norm. If the curve exists, the explicit expression can be given.

关键词： computer aided design Bézier curve degree reduction L2-norm tolerance.

De-interlacing technique based on total variation with spatial-temporal smoothness constraint

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Science in china(Series F) 2007年第4期50卷 561-575页

作者： YIN XueMin1,2,3, YUAN JianHua1,2, LU XiaoPeng1,2 & ZOU MouYan1,2 1 institute of electronics, Chinese Academy of Sciences, Beijing 100080, china 2 Graduate School, Chinese Academy of Sciences, Beijing 100039, china 3 Jiuquan Satellite Launch Center, Lanzhou 732750, china institute of electronics Chinese Academy of Sciences Beijing 100080 China

This paper introduces a new method of converting interlaced video to a progressively scanned video and image, The new method is derived from Bayesian framework with the spatial-temporal smoothness constraint and the MAP is done by minimizing the energy functional, The half-quadratic regularization method is used to solve the corresponding partial differential equations （PDEs）, This approach gives the improved results over the conventional de-interlacing methods, Two criteria are proposed in the paper, and they can be used to evaluate the performance of the de-interlacing algorithms,

关键词： video processing de-interlacing total variation spatio-temporai smoothness constraint PDEs half-quadratic regularization

Evolution of terraces Ⅰ–Ⅲ along the Anning River, western Sichuan, based on pollen records and terrace structure

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Science china Earth Sciences 2011年第1期54卷 127-135页

作者： CHENG JianWu1,2 1 institute of Geology, china Earthquake Administration, Beijing 100039, china 2 Earthquake Administration of Gansu Province, Lanzhou 730000, china institute of Geology China Earthquake Administration Beijing China Earthquake Administration of Gansu Province Lanzhou China

This study reconstructs the long-term evolution of river terraces over large spatial scales along the Anning River, western Sichuan, and identifies external factors controlling terrace formation. Pollen record analysis and terrace structure indicate that formation of the middle section of terraces I-III resulted from the interaction of changing climates and uplift of the margins of the Qinghai-Tibet Plateau. The relative influence of climate and uplift in terrace formation changes in different periods. The terraces reveal multiple, gradual uplift events on the eastern Qinghai-Tibet Plateau, which is of great significance for determining uplift mechanisms across the entire plateau.

关键词： Anning River in western Sichuan terrace formation pollen paleoclimate