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基于单节点重构改进小波包的电力系统谐波分析算法 被引量:13
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作者 尚秋峰 康丹 +1 位作者 李青 郭晓帅 《电力系统保护与控制》 EI CSCD 北大核心 2011年第3期74-77,94,共5页
在传统小波包算法中,虽然提高了频率分辨率,但是各子带存在产生虚假频率成分的情况,应用于电力系统谐波分析将产生严重的频率混叠现象。应用单节点重构改进小波包快速算法,利用快速傅里叶变换(FFT)和快速傅里叶逆变换(IFFT)对各子带信... 在传统小波包算法中,虽然提高了频率分辨率,但是各子带存在产生虚假频率成分的情况,应用于电力系统谐波分析将产生严重的频率混叠现象。应用单节点重构改进小波包快速算法,利用快速傅里叶变换(FFT)和快速傅里叶逆变换(IFFT)对各子带信号进行处理,并调整滤波器组使子带频带顺序排列。通过仿真实例将改进算法的结果与传统算法进行对比,结果证明,改进算法能更有效地避免重构信号中的频谱混叠和交错现象。 展开更多
关键词 小波包变换 谐波 频率混叠 交错 单节点重构
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基于ANSYS CFX的网络喷嘴内部流场计算 被引量:9
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作者 邱华 牟俊玲 +2 位作者 徐燃霞 葛明桥 苑志博 《纺织学报》 EI CAS CSCD 北大核心 2009年第2期104-108,共5页
为设计性能优良的用于化纤长丝网络加工的网络器,采用商业计算流体力学软件ANSYS CFX对网络器丝道内的可压缩流体进行模拟,并将模拟结果和以往的实验数据进行比较。结果表明,除了少数几个点外,计算结果和实验结果具有较好的一致性。此外... 为设计性能优良的用于化纤长丝网络加工的网络器,采用商业计算流体力学软件ANSYS CFX对网络器丝道内的可压缩流体进行模拟,并将模拟结果和以往的实验数据进行比较。结果表明,除了少数几个点外,计算结果和实验结果具有较好的一致性。此外,通过考察丝道纵向截面上的速度矢量的分布,认为丝道纵向截面上对称旋涡的分布有利于网络结的形成;通过考察横向截面上速度矢量分布,认为在较大的张力条件下,网络结不易形成;丝道中心处速度的大小决定了化纤长丝的开松程度。 展开更多
关键词 网络加工 丝道 流体计算 网络器性能
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农村体育发展的理论窠臼与实践反思——基于对X自然村村民非身体活动的行为考察 被引量:6
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作者 张庆武 《体育与科学》 CSSCI 北大核心 2016年第3期89-93,99,共6页
采用主题集成分析法、田野调查和案例分析法,基于交错性视域和理论对现有农村体育发展的困境和研究成果的差异困惑进行了研究范式的反思。研究认为:乡村公共体育空间术语应统筹农民体育概念丛的混乱;基于对X自然村村民的非身体活动考察... 采用主题集成分析法、田野调查和案例分析法,基于交错性视域和理论对现有农村体育发展的困境和研究成果的差异困惑进行了研究范式的反思。研究认为:乡村公共体育空间术语应统筹农民体育概念丛的混乱;基于对X自然村村民的非身体活动考察发现,村民几乎绝缘于现代体育活动但明显偏好于本土性的仪式性活动;前者主要源于慈善式的公共服务价值观以及乡村空间体育文化价值建构的乏力。农村体育呈现出了异质性特征,以后应对边缘性群体给予更多的关注。建构村落体育空间发展方面提出了内生代替植入的发展战略规划。对村落中的民间体育活动进行制度层面的保护和挖掘,进一步激发乡村体育空间的内生动力。 展开更多
关键词 身体活动 体育空间 村落 农民 交错性
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A computation design method for architectural artifacts adapted from traditional Kagome bamboo basketry techniques
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作者 Hiroyuki Shinohara Tung Hoi Peter Chan 《Frontiers of Architectural Research》 CSCD 2024年第2期249-264,共16页
This study is a digital form-finding and manual fabrication experiment in woven architectural design,with one traditional weaving style,Kagome,used to scale the craft up into an architectural-scale bamboo woven artifa... This study is a digital form-finding and manual fabrication experiment in woven architectural design,with one traditional weaving style,Kagome,used to scale the craft up into an architectural-scale bamboo woven artifact.Kagome is a trihexagonal pattern employed in traditional bamboo basketry as a triaxial weaving system,resulting in an object with a self-bracing capacity without the use of fasteners owing to its interlacing lattices.Although existing studies and tools have addressed triaxial weaving design and representation,the current consideration of the advantages of weaving with bamboo is insufficient.To address this research gap,this study develops a computational design method based on studies on bamboo basketry.This allows for the representation and exploration of design geometries using combinations of regular triangular meshes for the fabrication of Kagome woven bamboo artifacts.A full-scale mock-up was fabricated to evaluate the effectiveness of the method.The mock-up demonstrated the self-bracing properties of Kagome,but there were discrepancies between the mock-up and the design.Factors affecting bamboo weaving on an architectural scale have been identified within this study to inform future research on woven bamboo structures. 展开更多
关键词 Traditionalbamboo craft Triaxialmaterial interlacing BAMBOO Computational design methods Mesh block combinationsystem Architecturalwoven artifact
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Scatter correction method for cone-beam CT based on interlacing-slit scan 被引量:3
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作者 黄魁东 张华 +2 位作者 史仪凯 张亮 徐哲 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期515-521,共7页
Cone-beam computed tornography (CBCT) has the notable features of high efficiency and high precision, and is widely used in areas such as medical imaging and industrial non-destructive testing. However, the presence... Cone-beam computed tornography (CBCT) has the notable features of high efficiency and high precision, and is widely used in areas such as medical imaging and industrial non-destructive testing. However, the presence of the ray scatter reduces the quality of CT images. By referencing the slit collimation approach, a scatter correction method for CBCT based on the interlacing-slit scan is proposed. Firstly, according to the characteristics of CBCT imaging, a scatter suppression plate with interlacing slits is designed and fabricated. Then the imaging of the scatter suppression plate is analyzed, and a scatter correction Calculation method for CBCT based on the image fusion is proposed, which can splice out a complete set of scatter suppression projection images according to the interlacing-slit projection images of the left and the right imaging regions in the scatter suppression plate, and simultaneously complete the scatter correction within the fiat panel detector (FPD). Finally, the overall process of scatter suppression and correction is provided. The experimental results show that this method can significantly improve the clarity of the slice images and achieve a good scatter correction. 展开更多
关键词 cone-beam computed tomography scatter correction interlacing slits image fusion
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一个基于运动自适应去隔行算法的视频系统 被引量:3
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作者 刘陟 吕炳朝 康波 《现代电子技术》 2005年第16期89-91,共3页
在大多数现代高端视频产品中,逐行技术被广泛应用以获得比传统隔行系统质量更高的图像。本文讨论了现有各种算法的利弊,采用了一种基于运动自适应的算法,给出了这种算法的VLSI结构实现,并在此基础上构造了整个视频系统,给出了一个实用... 在大多数现代高端视频产品中,逐行技术被广泛应用以获得比传统隔行系统质量更高的图像。本文讨论了现有各种算法的利弊,采用了一种基于运动自适应的算法,给出了这种算法的VLSI结构实现,并在此基础上构造了整个视频系统,给出了一个实用的、高性能的逐行视频系统的实现。 展开更多
关键词 逐行 隔行 运动自适应 VLSI结构 视频系统
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Coolplus纤维加工工艺及其产品性能研究 被引量:3
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作者 关燕 刘亦军 +2 位作者 林旭 臧勇 王显琪 《棉纺织技术》 CAS CSCD 北大核心 2003年第9期5-8,共4页
详细分析了Coolplus纤维的结构特点 ,并与其他纤维进行了性能对比 ,介绍了Coolplus纤维与Ten celA 10 0纤维混纺纱的纺纱工艺技术要点及减少混纺纱毛羽的技术措施 ,并对Coolplus纤维与棉交织织物的织部工艺进行了探讨。通过测试分析Cool... 详细分析了Coolplus纤维的结构特点 ,并与其他纤维进行了性能对比 ,介绍了Coolplus纤维与Ten celA 10 0纤维混纺纱的纺纱工艺技术要点及减少混纺纱毛羽的技术措施 ,并对Coolplus纤维与棉交织织物的织部工艺进行了探讨。通过测试分析Coolplus纤维混纺针织品的吸湿排湿性能 。 展开更多
关键词 COOLPLUS纤维 加工工艺 结构特点 混纺纱 毛羽 交织织物 吸湿排湿性能 改性聚酯纤维
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网络丝生产工艺探讨 被引量:3
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作者 赵友云 王玉秀 《聚酯工业》 CAS 2002年第3期19-20,25,共3页
用HEBERLEINP2 12网络喷嘴 ,在法国ICBTFTF12E3加弹机上生产不同网络度和牢度的网络丝。探讨了网络张力、压缩空气压力等工艺条件与网络度和牢度的关系 ;优化工艺参数 ,生产的网络丝满足了市场多样化的需求。
关键词 网络丝 生产工艺 涤纶 DTY 加弹机
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Development of Sichuan Brocade with Imitating Embroidery Effect Based on Free-Floats Interlacing Weave 被引量:1
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作者 Dekun Ma Ming Cheng +3 位作者 Dan Zheng Xiaomin Fan Weijie Wang Jia Fang 《Journal of Textile Science and Technology》 2020年第1期11-18,共8页
Owing to the diversity of consumer’s demand, the traditional Sichuan brocade products have to be innovated in order to survive in a competitive environment. Since the construction of traditional Sichuan brocade was c... Owing to the diversity of consumer’s demand, the traditional Sichuan brocade products have to be innovated in order to survive in a competitive environment. Since the construction of traditional Sichuan brocade was composed of basic-weave, the surface of the fabric shows a regular interweaving planar texture and is difficult to represent a three-dimensional effect. Inspired by embroidery handcraft, this paper attempts to achieve the embroidery-like effect on the fabric through the jacquard process. Based on the multi-backed structure of traditional Sichuan brocade, we adopted the zoned-combination design mode and added extra free-floats interlacing weave in the area where we want to show the embroidered effect and arranged the interlacing points by referring to the feature of the pattern. As a result, designed Sichuan brocades by this method are capable of displaying embroidered effect with high realism and three-dimensionality. This approach improves the artistic effect of the traditional Sichuan brocade and provides a technical reference for further texture design of jacquard fabrics. 展开更多
关键词 Free-Floats interlacing Weave Imitating EMBROIDERY SICHUAN BROCADE
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Bounding Inequalities for Eigenvalues of Principal Submatrices
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作者 Achiya Dax 《Advances in Linear Algebra & Matrix Theory》 2019年第2期21-34,共14页
Ky Fan trace theorems and the interlacing theorems of Cauchy and Poincaré are important observations that characterize Hermitian matrices. In this note, we introduce a new type of inequalities which extend these ... Ky Fan trace theorems and the interlacing theorems of Cauchy and Poincaré are important observations that characterize Hermitian matrices. In this note, we introduce a new type of inequalities which extend these theorems. The new inequalities are obtained from the old ones by replacing eigenvalues and diagonal entries with their moduli. This modification yields effective bounding inequalities which are valid on a larger range of matrices. 展开更多
关键词 Cauchy interlacing THEOREM POINCARÉ interlacing THEOREM Ky Fan Trace Theorems NON-HERMITIAN MATRICES Normal MATRICES Bounding INEQUALITIES
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Evolutionary dynamics analysis of complex network with fusion nodes and overlap edges 被引量:1
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作者 YANG Yinghui LI Jianhua +2 位作者 SHEN Di NAN Mingli CUI Qiong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第3期549-559,共11页
Multiple complex networks, each with different properties and mutually fused, have the problems that the evolving process is time varying and non-equilibrium, network structures are layered and interlacing, and evolvi... Multiple complex networks, each with different properties and mutually fused, have the problems that the evolving process is time varying and non-equilibrium, network structures are layered and interlacing, and evolving characteristics are difficult to be measured. On that account, a dynamic evolving model of complex network with fusion nodes and overlap edges(CNFNOEs) is proposed. Firstly, we define some related concepts of CNFNOEs, and analyze the conversion process of fusion relationship and hierarchy relationship. According to the property difference of various nodes and edges, fusion nodes and overlap edges are subsequently split, and then the CNFNOEs is transformed to interlacing layered complex networks(ILCN). Secondly,the node degree saturation and attraction factors are defined. On that basis, the evolution algorithm and the local world evolution model for ILCN are put forward. Moreover, four typical situations of nodes evolution are discussed, and the degree distribution law during evolution is analyzed by means of the mean field method.Numerical simulation results show that nodes unreached degree saturation follow the exponential distribution with an error of no more than 6%; nodes reached degree saturation follow the distribution of their connection capacities with an error of no more than 3%; network weaving coefficients have a positive correlation with the highest probability of new node and initial number of connected edges. The results have verified the feasibility and effectiveness of the model, which provides a new idea and method for exploring CNFNOE's evolving process and law. Also, the model has good application prospects in structure and dynamics research of transportation network, communication network, social contact network,etc. 展开更多
关键词 complex network with fusion nodes and overlap edges(CNFNOEs) interlacing layered complex networks(ILCN) local world dynamic evolvement split saturation attraction factor
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Deleting Vertices and Interlacing Laplacian Eigenvalues 被引量:3
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作者 Baofeng WU Jiayu SHAO Xiying YUAN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2010年第2期231-236,共6页
The authors obtain an interlacing relation between the Laplacian spectra of a graph G and its subgraph G-U,which is obtained from G by deleting all the vertices in the vertex subset U together with their incident edge... The authors obtain an interlacing relation between the Laplacian spectra of a graph G and its subgraph G-U,which is obtained from G by deleting all the vertices in the vertex subset U together with their incident edges.Also,some applications of this interlacing property are explored and this interlacing property is extended to the edge weighted graphs. 展开更多
关键词 interlacing inequality EIGENVALUE SPECTRUM Laplacian matrix
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A New Method of Solving the Index Problem for Sturm-Liouville Eigenvalues
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作者 GUI-XIA WANG JIONG SUN 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2015年第4期1001-1012,共12页
Based on some recent results for interlacing eigenvalue intervals from 1-parameter families of se- quences of eigenvalue inequalities, a new method is given to solving the index problem for Sturm-Liouville eigenvalues... Based on some recent results for interlacing eigenvalue intervals from 1-parameter families of se- quences of eigenvalue inequalities, a new method is given to solving the index problem for Sturm-Liouville eigenvalues for coupled self-adjoint boundary conditions in the regular case. The key is a new characteristic principle for indices for Sturm-Liouville eigenvalues. The algorithm corresponding on the characteristic princi- ple are discussed, and numerical examples are presented to illustrate the theoretical results and show that the algorithm is valid. 展开更多
关键词 self-adjoint Sturm-Liouville problems indices of eigenvalues coupled boundary conditions Priiferangle interlacing Eigenvalue Intervals numerical computations.
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A Subspace Iteration for Calculating a Cluster of Exterior Eigenvalues
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作者 Achiya Dax 《Advances in Linear Algebra & Matrix Theory》 2015年第3期76-89,共14页
In this paper we present a new subspace iteration for calculating eigenvalues of symmetric matrices. The method is designed to compute a cluster of k exterior eigenvalues. For example, k eigenvalues with the largest a... In this paper we present a new subspace iteration for calculating eigenvalues of symmetric matrices. The method is designed to compute a cluster of k exterior eigenvalues. For example, k eigenvalues with the largest absolute values, the k algebraically largest eigenvalues, or the k algebraically smallest eigenvalues. The new iteration applies a Restarted Krylov method to collect information on the desired cluster. It is shown that the estimated eigenvalues proceed monotonically toward their limits. Another innovation regards the choice of starting points for the Krylov subspaces, which leads to fast rate of convergence. Numerical experiments illustrate the viability of the proposed ideas. 展开更多
关键词 EXTERIOR EIGENVALUES Symmetric Matrices SUBSPACE ITERATIONS interlacing Restarted Krylov Methods
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基于运动补偿的视频自适应去隔行算法
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作者 牛帆 李冬梅 李朝晖 《电视技术》 北大核心 2008年第z1期88-90,共3页
针对传统的去隔行算法存在的问题,提出了一种新的基于运动补偿的视频自适应去隔行算法,主要内容包括双向块匹配运动估计、自适应参考域值设置。测试结果表明本算法能够高质量地去除视频图像的隔行效应。
关键词 隔行效应 去隔行 双向块匹配运动估计 自适应参考域值设置 运动补偿
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Some Applications on the Method of Eigenvalue Interlacing for Graphs
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作者 LI Jian Xi CHANG An 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2008年第2期251-256,共6页
The Method of Eigenvalue Interlacing for Graphs is used to investigate some problems on graphs, such as the lower bounds for the spectral radius of graphs. In this paper, two new sharp lower bounds on the spectral rad... The Method of Eigenvalue Interlacing for Graphs is used to investigate some problems on graphs, such as the lower bounds for the spectral radius of graphs. In this paper, two new sharp lower bounds on the spectral radius of graphs are obtained, and a relation between the Laplacian spectral radius of a graph and the number of quadrangles in the graph is deduced. 展开更多
关键词 eigenvalues interlacing adjacency matrix Laplace matrix quotient matrix
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Relation between some variations of soil and surface vegetation and desertization in agriculture-pasture interlacing zone——An example from Kangbao County, North Hebei, China
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作者 SHENGXue-bing LIUYun-xia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第1期112-115,共4页
The studied agriculture\|pasture interlacing zone has its specific natural conditions, at which the natural systems are unstable, their self\|regulation capability is low and the equilibrium is easily broken, and henc... The studied agriculture\|pasture interlacing zone has its specific natural conditions, at which the natural systems are unstable, their self\|regulation capability is low and the equilibrium is easily broken, and hence the habitat is fairly vulnerable. During last 20 years the increasing population and livestock, over\|reclamation, over\|pasturing, over\|deforesting, and other intensified negative human activities in the zone resulted in coarsening of surface soil, decrease of organic mater content in soil, reduction of vegetation coverage, variation and degradation of flora structure, and hence in desertization of the land, although average of gales and sandstorms some decreased and the climate tended to be better in the region. However, the frequent sandstorms occurring in the springs of last and present years has attracted much attention. Investigations confirmed that the main cause for the phenomena is the unreasonable human activities rather than the natural factors. 展开更多
关键词 agriculture\|pasture interlacing zone SOIL SANDSTORM desertization
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On the Decomposition of a Bounded Closed Interval of the Real Line into Closed Sets
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作者 Edgar A. Cohen 《Advances in Pure Mathematics》 2013年第4期405-408,共4页
It has been shown by Sierpinski that a compact, Hausdorff, connected topological space (otherwise known as a continuum) cannot be decomposed into either a finite number of two or more disjoint, nonempty, closed sets o... It has been shown by Sierpinski that a compact, Hausdorff, connected topological space (otherwise known as a continuum) cannot be decomposed into either a finite number of two or more disjoint, nonempty, closed sets or a countably infinite family of such sets. In particular, for a closed interval of the real line endowed with the usual topology, we see that we cannot partition it into a countably infinite number of disjoint, nonempty closed sets. On the positive side, however, one can certainly express such an interval as a union of c disjoint closed sets, where c is the cardinality of the real line. For example, a closed interval is surely the union of its points, each set consisting of a single point being closed. Surprisingly enough, except for a set of Lebesgue measure 0, these closed sets can be chosen to be perfect sets, i.e., closed sets every point of which is an accumulation point. They even turn out to be nowhere dense (containing no intervals). Such nowhere dense, perfect sets are sometimes called Cantor sets. 展开更多
关键词 CANTOR SETS CARDINALITY DISJOINT Closed SETS DYADIC Representation interlacing DYADIC Expansions Generators of SETS Nowhere Dense
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DSPs/FPGAs Comparative Study for Power Consumption, Noise Cancellation, and Real Time High Speed Applications
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作者 Alon Hayim Michael Knieser Maher Rizkalla 《Journal of Software Engineering and Applications》 2010年第4期391-403,共13页
Adaptive noise data filtering in real-time requires dedicated hardware to meet demanding time requirements. Both DSP processors and FPGAs were studied with respect to their performance in power consumption, hardware a... Adaptive noise data filtering in real-time requires dedicated hardware to meet demanding time requirements. Both DSP processors and FPGAs were studied with respect to their performance in power consumption, hardware architecture, and speed for real time applications. For testing purposes, real time adaptive noise filters have been implemented and simulated on two different platforms, Motorola DSP56303 EVM and Xilinx Spartan III boards. This study has shown that in high speed applications, FPGAs are advantageous over DSPs with respect of their speed and noise reduction because of their parallel architecture. FPGAs can handle more processes at the same time when compared to DSPs, while the later can only handle a limited number of parallel instructions at a time. The speed in both processors impacts the noise reduction in real time. As the DSP core gets slower, the noise removal in real time gets harder to achieve. With respect to power, DSPs are advantageous over FPGAs. FPGAs have reconfigurable gate structure which consumes more power. In case of DSPs, the hardware has been already configured, which requires less power consumption? FPGAs are built for general purposes, and their silicon area in the core is bigger than that of DSPs. This is another factor that affects power consumption. As a result, in high frequency applications, FPGAs are advantageous as compared to DSPs. In low frequency applications, DSPs and FPGAs both satisfy the requirements for noise cancelling. For low frequency applications, DSPs are advantageous in their power consumption and applications for the battery power devices. Software utilizing Matlab, VHDL code run on Xilinix system, and assembly running on Motorola development systems, have been used for the demonstration of this study. 展开更多
关键词 Four QUADRANT (4Q) Converter interlacing TRACTION Systems Power Quality Analysis
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An Automatic Recognizer for Iraqi License Plates Using ELMAN Neural Network
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作者 Abdul Hussein Mohsin Abbas H. Hassin Iman Qais Abdul Jaleel 《Journal of Software Engineering and Applications》 2010年第12期1163-1166,共4页
License plate recognition system plays an important role in many applications. An automatic recognizer for Iraqi License Plates using ELMAN Neural network is proposed in this manuscript. The processing procedures are ... License plate recognition system plays an important role in many applications. An automatic recognizer for Iraqi License Plates using ELMAN Neural network is proposed in this manuscript. The processing procedures are developed in several stages. Experimental results are reported in the end of the paper to illustrate the performance of the proposed method. 展开更多
关键词 FOUR QUADRANT (4Q) CONVERTER interlacing TRACTION Systems Power Quality Analysis
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