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基于神经网络的线图数据处理模型 被引量:1
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作者 陈东 《机械设计与制造》 北大核心 2005年第4期46-48,共3页
提出了一种能够一次处理一组线图数据的新方法,基于神经网络的基本原理,建立了能够处理线图数据的神经网络模型,并且详细的讨论了径向基函数神经网络的具体应用。成为处理线图数据尤其是多线图数据的有利工具。处理过程主要分成三步:(1... 提出了一种能够一次处理一组线图数据的新方法,基于神经网络的基本原理,建立了能够处理线图数据的神经网络模型,并且详细的讨论了径向基函数神经网络的具体应用。成为处理线图数据尤其是多线图数据的有利工具。处理过程主要分成三步:(1)采集数据,建立输入、输出矩阵,(2)训练网络模型,(3)检验误差。文中给出了应用实例及误差分析。 展开更多
关键词 多线图 矩阵输入 矩阵输出 神经网络
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Low-dimensional multi-spectral space for color reproduction based on nonnegative constrained principal component analysis 被引量:1
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作者 王莹 曾平 +1 位作者 罗雪梅 谢琨 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期486-490,共5页
In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonne... In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonnegative constrained principal component analysis method is proposed to construct a low-dimensional multi-spectral space and accomplish the conversion between the new constructed space and the multispectral space. First, the reason behind the negative data is analyzed and a nonnegative constraint is imposed on the classic PCA. Then a set of nonnegative linear independence weight vectors of principal components is obtained, by which a lowdimensional space is constructed. Finally, a nonlinear optimization technique is used to determine the projection vectors of the high-dimensional multi-spectral data in the constructed space. Experimental results show that the proposed method can keep the reconstructed spectral data in [ 0, 1 ]. The precision of the space created by the proposed method is equivalent to or even higher than that by the PCA. 展开更多
关键词 spectral color science nonnegative constrained principal component analysis low-dimensional spectral space nonlinear optimization multi-spectral images spectral reflectance
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Prediction of Demand and Tendency of the Book Market in China
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作者 李海霞 孙学良 赵黎明 《Transactions of Tianjin University》 EI CAS 2002年第3期216-220,共5页
The prediction model of the demand of the book market in China from the quantitative angle is established,and the total demand of the books for years from 2002 to 2004 is predicted.The effects of the gross domestic pr... The prediction model of the demand of the book market in China from the quantitative angle is established,and the total demand of the books for years from 2002 to 2004 is predicted.The effects of the gross domestic product,household consumption,price and population on the demand of books are also analyzed.In the end,it is summarized that the acceleration of the development of Chinese book industry,the refinement of the books,the innovation of the advertisement,the series of the structure and the steady increase of the price will become the remarkable characteristics of the book market. 展开更多
关键词 book market DEMAND multiple linear regression
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CEE-Gr:A Global Router with Performance Optimization Under Multi-Constraints
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作者 张凌 经彤 +3 位作者 洪先龙 许静宇 XiongJinjun HeLei 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第5期508-515,共8页
A global routing algorithm with performance optimization under multi constraints is proposed,which studies RLC coupling noise,timing performance,and routability simultaneously at global routing level.The algorithm is... A global routing algorithm with performance optimization under multi constraints is proposed,which studies RLC coupling noise,timing performance,and routability simultaneously at global routing level.The algorithm is implemented and the global router is called CEE Gr.The CEE Gr is tested on MCNC benchmarks and the experimental results are promising. 展开更多
关键词 VLSI/ULSI physical design global routing multi constraints performance optimization
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Hypergraph High-Dimension Clustering Algorithm for Optimized Cooperative Wireless Multicast 被引量:1
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作者 Chen Yueyun Liu Wei Lin Fuhong Zhou Xianwei 《China Communications》 SCIE CSCD 2012年第8期135-139,共5页
In order to guarantee the wireless multicast throughput at a minimum cost, we propose a layered hypergraph high-dimension clustering algorithm (LayerHC) considering the channels and statistical locations of mobile mem... In order to guarantee the wireless multicast throughput at a minimum cost, we propose a layered hypergraph high-dimension clustering algorithm (LayerHC) considering the channels and statistical locations of mobile members. The algorithm can achieve a minimum multicast spanning tree to obtain a minimum number of relays and effective cooperative areas with low computational complexity. 展开更多
关键词 cooperative wireless multicast HYPERGRAPH high-dimension clustering
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Imaging technologies in oilfield applications 被引量:2
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作者 XIE C.G. NORTH R. +3 位作者 WILT M. ZHANG P. DENACLARA H. LEVESQUE C. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第12期1394-1400,共7页
In this paper, we describe some recent imaging technologies developed by Schlumberger for oilfield downhole mul- tiphase flow production logging (PL) and cross-well electromagnetic (EM) survey applications. FloScan Im... In this paper, we describe some recent imaging technologies developed by Schlumberger for oilfield downhole mul- tiphase flow production logging (PL) and cross-well electromagnetic (EM) survey applications. FloScan Imager (FSITM) has been introduced as a 3-phase oil/gas/water flow PL tool for deviated and horizontal wells. FSI sensors can map fluid velocity and holdup profiles along a vertical diameter of the wellbore at every survey depth, enabling a robust estimate of the individual phase flow rates in complex flow regimes. The cross-well EM survey is based on cross-borehole induction logging technique and provides resistivity distribution at a reservoir scale. It is a useful tool for reservoir management and is most effective in dynamic fields where fluid saturations are variable in time and space. The tool can be used to identify (water or steam) flooded and bypassed regions. By monitoring changes in the resistivity spatial distribution with time, cross-well EM survey is very effective at mapping inter-well temperature and structure. Some field examples are shown for both FloScan Imager PL tool and cross-well resistivity imaging survey. 展开更多
关键词 OILFIELD Production logging (PL) Multiphase flow IMAGING TOMOGRAPHY Cross-well resistivity
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PROJECTION BASED STATISTICAL FEATURE EXTRACTION WITH MULTISPECTRAL IMAGES AND ITS APPLICATIONS ON THE YELLOW RIVER MAINSTREAM LINE DETECTION 被引量:1
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作者 Zhang Yanning Zhang Haichao +2 位作者 Duan Feng Liu Xuegong Han Lin 《Journal of Electronics(China)》 2009年第3期359-365,共7页
Mainstream line is significant for the Yellow River situation forecasting and flood control.An effective statistical feature extraction method is proposed in this paper.In this method, a between-class scattering matri... Mainstream line is significant for the Yellow River situation forecasting and flood control.An effective statistical feature extraction method is proposed in this paper.In this method, a between-class scattering matrix based projection algorithm is performed to maximize between-class differences, obtaining effective component for classification;then high-order statistics are utilized as the features to describe the mainstream line in the principal component obtained.Experiments are performed to verify the applicability of the algorithm.The results both on synthesized and real scenes indicate that this approach could extract the mainstream line of the Yellow River automatically, and has a high precision in mainstream line detection. 展开更多
关键词 Mainstream line PROJECTION Between-class scatter matrix High-order statistics SKEWNESS
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On k-Star Arboricity of Graphs
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作者 陶昉昀 林文松 《Journal of Donghua University(English Edition)》 EI CAS 2014年第3期335-338,共4页
A star forest is a forest whose components are stars. The star arboricity of a graph G,denoted by sa( G),is the minimum number of star forests needed to decompose G. Let k be a positive integer. A k-star forest is a... A star forest is a forest whose components are stars. The star arboricity of a graph G,denoted by sa( G),is the minimum number of star forests needed to decompose G. Let k be a positive integer. A k-star forest is a forest whose components are stars of order at most k + 1. The k-star arboricity of a graph G,denoted by sak( G),is the minimum number of k-star forests needed to decompose G. In this paper,it is proved that if any two vertices of degree 3 are nonadjacent in a subcubic graph G then sa2( G) ≤2.For general subcubic graphs G, a polynomial-time algorithm is described to decompose G into three 2-star forests. For a tree T and[Δ k, T)/k]t≤ sak( T) ≤[Δ( T)- 1/K]+1,where Δ( T) is the maximum degree of T.kMoreover,a linear-time algorithm is designed to determine whether sak( T) ≤m for any tree T and any positive integers m and k. 展开更多
关键词 star arboricity k-star arboricity linear k-arboricity cubic graphs subcubic graphs
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Local curve fitting based Lagrange multiplier selection for Id-slice in multi-view video coding 被引量:1
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作者 Shi-fang XU Guo-bin CHEN +1 位作者 Hua-dong PAN Ji-lin LIU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第6期778-785,共8页
The rate and distortion of Id-slice do not fit the globally linear relationship on a logarithmic scale. Lagrange multiplier selection methods based on the globally linear approximate relationship are neither efficient... The rate and distortion of Id-slice do not fit the globally linear relationship on a logarithmic scale. Lagrange multiplier selection methods based on the globally linear approximate relationship are neither efficient nor optimal for multi-view video coding (MVC). To improve the coding efficiency of MVC, a local curve fitting based Lagrange multiplier selection method is proposed in this paper, where Lagrange multipliers are selected according to the local slopes of the approximate curves. Experi-mental results showed that the proposed method improves the coding efficiency. Up to 2.5 dB gain was achieved at low bitrates. 展开更多
关键词 Id-slice Lagrange multiplier Local curve fitting Multi-view video coding (MVC)
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A fake projective plane constructed from an elliptic surface with multiplicities (2,4) 被引量:1
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作者 KEUM JongHae 《Science China Mathematics》 SCIE 2011年第8期1665-1678,共14页
Given any (2,4)-elliptic surface with nine smooth rational curves,eight (2)-curves and one (3)-curve,forming a Dynkin diagram of type [2,2][2,2][2,2][2,2,3],we show that a fake projective plane can be constructed from... Given any (2,4)-elliptic surface with nine smooth rational curves,eight (2)-curves and one (3)-curve,forming a Dynkin diagram of type [2,2][2,2][2,2][2,2,3],we show that a fake projective plane can be constructed from it by taking a degree 3 cover and then a degree 7 cover.We also determine the types of singular fibres of such a (2,4)-elliptic surface. 展开更多
关键词 fake projective plane properly elliptic surface cyclic covering
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Self-assembly and chemical processing of block copolymers:A roadmap towards a diverse array of block copolymer nanostructures 被引量:3
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作者 WYMAN Ian LIU GuoJun 《Science China Chemistry》 SCIE EI CAS 2013年第8期1040-1066,共27页
Block copolymers can yield a diverse array of nanostructures.Their assembly structures are influenced by their inherent structures,and the wide variety of structures that can be prepared especially becomes apparent wh... Block copolymers can yield a diverse array of nanostructures.Their assembly structures are influenced by their inherent structures,and the wide variety of structures that can be prepared especially becomes apparent when one considers the number of routes available to prepare block copolymer assemblies.Some examples include self-assembly,directed assembly,coupling,as well as hierarchical assembly,which can yield assemblies having even higher structural order.These assembly routes can also be complemented by processing techniques such as selective crosslinking and etching,the former technique leading to permanent structures,the latter towards sculpted and the combination of the two towards permanent sculpted structures.The combination of these pathways provides extremely versatile routes towards an exciting variety of architectures.This review will attempt to highlight destinations reached by LIU Guojun and coworkers following these pathways. 展开更多
关键词 block copolymers SELF-ASSEMBLY chemical processing CROSSLINKING
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An efficient algorithm for factoring polynomials over algebraic extension field 被引量:1
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作者 SUN Yao WANG DingKang 《Science China Mathematics》 SCIE 2013年第6期1155-1168,共14页
An efficient algorithm is proposed for factoring polynomials over an algebraic extension field defined by a polynomial ring modulo a maximal ideal. If the maximal ideal is given by its CrSbner basis, no extra Grbbner ... An efficient algorithm is proposed for factoring polynomials over an algebraic extension field defined by a polynomial ring modulo a maximal ideal. If the maximal ideal is given by its CrSbner basis, no extra Grbbner basis computation is needed for factoring a polynomial over this extension field. Nothing more than linear algebraic technique is used to get a characteristic polynomial of a generic linear map. Then this polynomial is factorized over the ground field. From its factors, the factorization of the polynomial over the extension field is obtained. The algorithm has been implemented in Magma and computer experiments indicate that it is very efficient, particularly for complicated examples. 展开更多
关键词 algorithm FACTORIZATION algebraic extension field
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