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Physico-Chemical Properties and Laboratory Hyperspectral Reflectance of Coastal Saline Soil in Shangyu City of zhejiang Province, China

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Pedosphere 2003年第3期13卷 193-198页

作者： SHI ZHOU, HUANG MINGXIANG and LI YANinstitute of Agricultural Remote Sensing and information System, zhejiang University, hangzhou 310029 (China) institute of Agricultural Remote Sensing and information System Zhejiang University Hangzhou 310029 China

4. and 50 composite soil samples were collected, respectively, from twoagricultural fields, that were enclosed and reclaimed from coastal tidal-flat areas in 1996 and 1984.espectively, in Shangyu of zhejiang Province, China, to investigate the physico-chemicalproperties and the hyperspectral characteristics of the saline soils and to make an assessment ontheir relationships. The reflectance spectra of saline soils were measured using a spectroradiometerin laboratory. The mean spectral curves of the saline soils from the two sites different inreclamation year showed that the saline soil taken from the recently reclaimed land with highersalinity demonstrated a lower reflectance intensity in the spectral region from about 550 nm to 2300nm. In addition, nine absorption bands, i.e., 4.8 nm, 530 nm, 670 nm, 880 nm, 94. nm, 14.0 nm, 1900nm, 2 200 nm and 2 300 nm, were chosen as the spectral bands to investigate the relationshipsbetween soil physico-chemical properties by means of Pearson correlation analysis. Finally, thefirst two principal components were calculated from nine absorption bands and used to discriminatethe saline soil samples taken from two sampled fields. The results indicate that it is feasible todetect physico-chemical properties of saline soils from fields reclaimed for varying time periods onthe basis of the hyperspectral data.

关键词： coast hyperspectral reclamation saline soils

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Low-complexity distributed differential spacetime coding scheme for amplify-and-forward cooperative networks

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science in China(Series F) 2009年第8期52卷 1418-1427页

作者： YU XiangBin1,2, BI GuangGuo3 & XU WeiYe4.1 College of information science and technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China 2 department of Electronic Engineering, City University of Hong Kong, Hong Kong, China 3 National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096, China 4.department of Communication Engineering, Nanjing institute of technology, Nanjing 211167, China College of information science and technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China department of Electronic Engineering City University of Hong Kong Hong Kong China National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China department of Communication Engineering Nanjing Institute of Technology Nanjing 211167 China

By introducing a space-time coding scheme based on amicable orthogonality, we develop a distributed differential space-time coding scheme with the amplify-and-forward （AF） method for wireless cooperative networks. The scheme requires no knowledge of the channel state information at both transmitters and receivers, and effectively decreases the realization complexity due to no channel estimation. Moreover, it has lower decoding complexity and higher coding advantage than the existing scheme, thus avoiding the shortcoming of exponential decoding complexity of some existing schemes. According to the pairwise error probability （PEP） analysis of the system, the power allocations of source and relay terminals are jointly optimized, and as a result, the PEP is minimized, which will provide a helpful guideline for system design. Numerical calculation and simulation results show that the developed scheme is superior to the existing scheme. Moreover, the scheme with optimal power allocation yields obvious performance improvement over that with equal power allocation.

关键词： differential space-time coding cooperative communication amplify-and-forward method power allocation

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Image stylization with enhanced structure on GPU

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science China(information sciences) 2012年第5期55卷 1093-1105页

作者： LI Ping 1,SUN HanQiu 1,SHENG Bin 1,2 & SHEN JianBing 3 1 department of Computer science and Engineering,The Chinese University of Hong Kong,Hong Kong,China 2 department of Computer science and Engineering,Shanghai Jiao Tong University,Shanghai 20024.,China 3 School of Computer science and technology,Beijing institute of technology,Beijing 100081,China 1. department of Computer science and Engineering The Chinese University of Hong Kong Hong Kong China2. Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China3. School of Computer Science and Technology Beijing Institute of Technology Beijing 100081 China

This paper presents a graphics processing unit (GPU) based stylization approach that preserves the fine structure between the original and the stylized images using gradient *** abstraction and painterly stylization methods focused on contrast manipulation only,and thus the detailed salient structures of the input images are always destroyed when performing the current stylization techniques because of limitations like unavoidable salience information loss caused by contrast *** propose an image structure map to naturally model the fine structure existing in the original ***-based structure tangent generation and tangent-guided image morphology are used to construct the structure *** image structure map,unlike an edge map,not only systematically models the boundary information within the imagery but also accentuates the underlying inner structure detail for further *** facilitate the final stylization via parallel bilateral grid and structure-aware stylizing optimization on a GPU-CUDA platform in real *** multiple experiments,the proposed method consistently demonstrates efficient and high quality image stylization performance.

关键词： image stylization non-photorealistic rendering real-time processing GPU image abstraction

Influence of magnetic current on the ground state entanglement in an isotropic transverse XY chain

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Progress in Natural science:Materials International 2007年第10期17卷 1147-1151页

作者： Liu Dan1,2 , Zhang Yong3 and Long Guilu1,2(1. Key Laboratory for Atomic and Molecular Nanosciences, and department of Physics, Tsinghua University, Beijing 100084. China 2. Center of Quantum information science and{4., Tsinghua National Laboratory for information science and{4., Beijing 100084. China 3. institute of Physics, School of sciences, Beijing University of Posts and Telecommunications, Beijing 100876, China) Key Laboratory for Atomic and Molecular Nanosciences and Department of Physics Tsinghua University Beijing 100084 China Center of Quantum information science and technology Tsinghua National Laboratory for information Science and Technology Beijing 100084 China institute of Physics School of Sciences Beijing University of Posts and Telecommunications Beijing 100876 China

We study the ground state entanglement in a three-qubit XY chain under the influence of a magnetization current. It is found that the ground state changes from a W state to a disentangled state as the magnetic field varies. When the Lagrange multiplier λ>3, namely under a strong magnetic current, the ground state holds onto a W state for a large range of the magnetic field strength. A phase transition to the magnetization-current phase occurs under a certain condition.

关键词： Heisenberg-XY chain magnetic-current phase transition.

An Improved Heuristic Ant-Clustering Algorithm

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计算机工程与应用 2004年第29期40卷 133-134,158页

作者： YunfeiChen YushuLiu JihaiZhao departmentofComputerscienceandEngineering SchoolofInformationScienceandTechnologyBeijingInstituteofTechnologyBeijing100081

An improved heuristic ant-clustering algorithm(HAC)is presented in this paper.A device of ’memory bank’ is proposed,which can bring forth heuristic knowledge guiding ant to move in the bi-dimension grid *** device lowers the randomness of ants’ moving and avoids the producing of"un-assigned data object".We have made some experiments on real data sets and synthetic data *** results demonstrate that HAC has superiority in misclassification error rate and runtime over the classical algorithm.

关键词：蚁群聚类算法记忆存储体人工智能启发式知识引导

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L1/2 regularization

science China(information sciences) 2010年第6期53卷 1159-1169页

作者： XU ZongBen 1 , ZHANG Hai 1,2 , WANG Yao 1 , CHANG XiangYu 1 & LIANG Yong 3 1 institute of information and System science, Xi'an Jiaotong University, Xi'an 71004., China 2 department of Mathematics, Northwest University, Xi'an 710069, China 3 University of science and technology, Macau 999078, China 1. institute of information and System science Xi’an Jiaotong University Xi’an 710049 China2. Department of Mathematics Northwest University Xi’an 710069 China3. University of Science and Technology Macau 999078 China

In this paper we propose an L1 /2 regularizer which has a nonconvex *** L 1/2 regularizer is shown to have many promising properties such as unbiasedness, sparsity and oracle properties.A reweighed iterative algorithm is proposed so that the solution of the L 1/2 regularizer can be solved through transforming it into the solution of a series of L 1 *** solution of the L 1/2 regularizer is more sparse than that of the L 1 regularizer, while solving the L 1/2 regularizer is much simpler than solving the L 0 *** experiments show that the L 1/2 regularizer is very useful and efficient, and can be taken as a representative of the Lp(0 < p < 1) regularizer.

关键词： machine learning variable selection regularizer compressed sensing

Communication network designing:Transmission capacity,cost and scalability

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science China(information sciences) 2012年第11期55卷 2454-2465页

作者： ZHANG GuoQiang1,2,3 & ZHANG GuoQing1 1institute of computing technology,Chinese Academy of sciences,Beijing 100190,China 2School of Computer science and technology,Nanjing Normal University,Nanjing 21004.,China 3Provincial Key Laboratory for Computer information Processing technology,Soochow University,Suzhou 215000,China 1. institute of computing technology Chinese Academy of Sciences Beijing 100190 China2. School of Computer Science and Technology Nanjing Normal University Nanjing 210046 China3. Provincial Key Laboratory for Computer Information Processing Technology Soochow University Suzhou 215000 China

Despite the growing number of works centering around the traffic dynamics on complex networks,these researches still have some common shortcomings,e.g.,too simple traffic flow model and lack of considerations for the designing cost and scalability *** paper builds on a more realistic traffic flow model,and offers a holistic view on the network designing *** addition to the extensively studied transmission capacity,this paper takes designing cost and scalability as two other designing objectives,and presents a quantitative study of how different designing choices independently and collectively influence these objectives by the introduction of a cartesian coordinate *** is shown that different kinds of network topologies display different shapes of achievable solution spaces and exhibit different abilities to achieve cost-effective and scalable *** particular,we find the philosophy underlying empirical network designing and engineering today fails to meet the cost-effective and scalable designing requirements,and propose a cost-effective and scalable designing scheme for BA-like networks,i.e.,the efficient routing combined with effective betweenness based link bandwidth *** addition,when designing a thoroughly new network from the beginning,we find that ER network is a good candidate to achieve cost-effective and scalable designing in most settings.

关键词： cost-effective communication network designing network transmission efficiency network topology traffic dynamics next generation network scalable network designing

Study on Omni- directional Vision System Calibration Method Based on Line

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微计算机信息 2006年第34期 262-264页

作者： (School of information science & Engineering, Northeastern University)Wang,Yu Xu,Xinhe (The department of automation,North China Electric Power University)Wang,Yong (Changchun institute of{4.)

This paper introduces the study on omni- directional vision system calibration method using central catadioptric projection property of space line. The catadioptric image point of space line was captured applied ray- tracing algorithm. A conic fitting algo- rithm based on least- square theory was raised which be used in catadioptric image fitting of line. System imaging parameter was de- termined by cholsky decomposition and omni- directional vision system was calibration. The calibration experiment on real omni- di- rectional vision system verifies its effect.

关键词： omni-directional vision system calibration conics fit ray-tracing algorithm

l-SkyDiv query:Effectively improve the usefulness of skylines

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science China(information sciences) 2010年第9期53卷 1785-1799页

作者： HUANG ZhenHua1,2*,XIANG Yang1 & LIN ZiYu3 1department of Computer science and technology,Tongji University,Shanghai 201804.China 2The Key Laboratory of Embedded System and Service computing,Ministry of Education,Tongji University,Shanghai 200092,China 3department of Computer science and technology,Peking University,Beijing 100871,China 1. department of Computer science and technology Tongji University Shanghai 201804 China2. The Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 200092 China3. Department of Computer Science and Technology Peking University Beijing 100871 China

Skyline query processing has recently received a lot of attention in database *** a set of multi-dimensional objects,the skyline query finds the objects that are not dominated by *** the best of our knowledge,the existing researches mainly focus on how to efficiently return the whole skyline ***,as the cardinality and dimensionality of input dataset increase,the number of skylines grows exponentially,and hence this "huge" skyline set is completely useless to *** by the above fact,in this paper,we present a novel type of l-SkyDiv query,which only returns l skylines having maximum diversity,to improve the usefulness of skyline ***,we prove that the l-SkyDiv query belongs to the NP-Hard problem theoretically,and propose three efficient heuristic algorithms whose time complexities are polynomial to fast implement the proposed ***,we present detailed theoretical analyses and extensive experiments,demonstrating that our algorithms are both efficient and effective.

关键词： skyline query diversity heuristic algorithm query optimization performance evaluation