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双馈式可变速抽水蓄能机组无功特性分析 被引量:12
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作者 王欣竹 韩民晓 Bitew Girmaw Teshager 《电网技术》 EI CSCD 北大核心 2019年第8期2918-2924,共7页
分析双馈式可变速抽水蓄能机组的无功输出特性,对于提高机组并网运行能力及电力系统电压稳定性具有重要意义。提出了一种基于V形曲线分析机组定子侧无功特性及调节机理的方法。建立双馈电机等效电路及数学模型,分析不同运行工况下双馈... 分析双馈式可变速抽水蓄能机组的无功输出特性,对于提高机组并网运行能力及电力系统电压稳定性具有重要意义。提出了一种基于V形曲线分析机组定子侧无功特性及调节机理的方法。建立双馈电机等效电路及数学模型,分析不同运行工况下双馈电机各电气量的相量关系,得到定子电流随转子电压变化的V形曲线。研究了不同运行工况下V形曲线变化情况,重点分析了有功功率、转差率对V形曲线变化影响。基于Matlab/Simulink平台分别进行稳态和动态仿真验证,仿真结果表明双馈异步电机具备类似于同步电机的无功调节特性,证明了V形曲线法对于系统无功特性分析结果的正确性和有效性。 展开更多
关键词 双馈式可变速抽水蓄能 相量模式 V形曲线 无功特性
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Modeling and monitoring of nonlinear multi-mode processes based on similarity measure-KPCA 被引量:10
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作者 WANG Xiao-gang HUANG Li-wei ZHANG Ying-wei 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第3期665-674,共10页
A new modeling and monitoring approach for multi-mode processes is proposed.The method of similarity measure(SM) and kernel principal component analysis(KPCA) are integrated to construct SM-KPCA monitoring scheme,wher... A new modeling and monitoring approach for multi-mode processes is proposed.The method of similarity measure(SM) and kernel principal component analysis(KPCA) are integrated to construct SM-KPCA monitoring scheme,where SM method serves as the separation of common subspace and specific subspace.Compared with the traditional methods,the main contributions of this work are:1) SM consisted of two measures of distance and angle to accommodate process characters.The different monitoring effect involves putting on the different weight,which would simplify the monitoring model structure and enhance its reliability and robustness.2) The proposed method can be used to find faults by the common space and judge which mode the fault belongs to by the specific subspace.Results of algorithm analysis and fault detection experiments indicate the validity and practicability of the presented method. 展开更多
关键词 process monitoring kernel principal component analysis (KPCA) similarity measure subspace separation
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Correlation of the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma 被引量:8
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作者 Shenjiang Li Xiangsheng Xiao +3 位作者 Shiyuan Liu Huimin Li Chengzhou Li Chenshi Zhang 《The Chinese-German Journal of Clinical Oncology》 CAS 2007年第4期345-349,共5页
Objective:To evaluate the correlation of the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma(SBA).Methods:46 patients with solitary bronchogenic adenocarci... Objective:To evaluate the correlation of the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma(SBA).Methods:46 patients with solitary bronchogenic adenocarcinomas (SBA)(diameter≤4 cm)underwent multi-location dynamic contrast material-enhanced(nonionic contrast material was administrated via the antecubital vein at a rate of 4 mL/s by using an autoinjector 90 mL,4×5 mm or 4×2.5 mm scanning mode with stable table were performed)serial CT.Precontrast and postcontrast attenuation on every scan was recorded.Perfusion (PBA),peak height(PHBA),ratio of peak height of the SPN to that of the aorta(BA-to-A ratio)and mean transit time(MTT)were calculated.The correlation between peak height of the aorta(PHA)and parameters of the SBA(PHBA,BA-to-A ratio,PBA,and MTT)and those among parameters of the SBA were assessed by means of linear regression analysis.Regression equation among parameters of the SBA were obtain by means of stepwise regression.Results:The correlation between the SBA peak height(PHBA,36.78 HU±12.02)and the aortic peak height(PHA)was significant(r=0.506,P<0.0001).No significant cor- relation was found between the BA-to-Apeak height ratio(15.33%±4.55)and the aortic peak height(r=0.130,P=0.388> 0.05)as it was between the SBA perfusion(PBA,31.86 mL/min/100 g±9.74)and the aortic peak height(r=0.049,P=0.749 >0.05).The SBA perfusion correlated with the PHBA and the BA-to-A peak height ratio(r=0.394,P=0.007<0.05;r=0.407, P=0.005<0.05).The PHBA correlated positively with the BA-to-A peak height ratio(r=0.781,P<0.0001).Mean transit time was 14.84 s±5.52.PBA=18.500+0.872×BA-to-A ratio.BA-to-A ratio=4.467+0.295×PHBA.Conclusion:The linear correlation between the SBA perfusion and BA-to-Aratio and that between BA-to-Aratio and PHBA can be expressed by equation. It is possible to design a simpler scanning procedure of investigation of bronchogenic adenocarcinoma angiogenesis. 展开更多
关键词 bronchogenic adenocarcinoma blood flow pattern CT quantifiable parameters linear correlation
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Scheme for Implementing Quantum Search Algorithm in a Cluster State Quantum Computer
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作者 WANG Yan-Hui ZHANG Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1487-1490,共4页
Using cluster state and single qubit measurement one can perform the one-way quantum computation. Here we give a detailed scheme for realizing a modified Grover search algorithm using measurements on cluster state. We... Using cluster state and single qubit measurement one can perform the one-way quantum computation. Here we give a detailed scheme for realizing a modified Grover search algorithm using measurements on cluster state. We give the measurement pattern for the cluster-state realization of the algorithm and estimated the number of measurement needed for its implementation. It is found that O(2^3n/^2n^2) number of single qubit measurements is required for its realization in a cluster-state quantum computer. 展开更多
关键词 cluster state long algorithm control-phase gate measurement pattern
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SHAPE-BASED TIME SERIES SIMILARITY MEASURE AND PATTERN DISCOVERY ALGORITHM
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作者 ZengFanzi QiuZhengding +1 位作者 LiDongsheng YueJianhai 《Journal of Electronics(China)》 2005年第2期142-148,共7页
Pattern discovery from time series is of fundamental importance. Most of the algorithms of pattern discovery in time series capture the values of time series based on some kinds of similarity measures. Affected by the... Pattern discovery from time series is of fundamental importance. Most of the algorithms of pattern discovery in time series capture the values of time series based on some kinds of similarity measures. Affected by the scale and baseline, value-based methods bring about problem when the objective is to capture the shape. Thus, a similarity measure based on shape, Sh measure, is originally proposed, andthe properties of this similarity and corresponding proofs are given. Then a time series shape pattern discovery algorithm based on Sh measure is put forward. The proposed algorithm is terminated in finite iteration with given computational and storage complexity. Finally the experiments on synthetic datasets and sunspot datasets demonstrate that the time series shape pattern algorithm is valid. 展开更多
关键词 Shape similarity measure Pattern discovery algorithm Time series data mining
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Relativistic Consistent Angular-Momentum Projected Shell-Model: Relativistic Mean Field 被引量:3
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作者 LIYan-Song LONGGui-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期429-434,共6页
We develop a relativistic nuclear structure model, relativistic consistent angular-momentum projected shell-model (RECAPS), which combines the relativistic mean-field theory with the angular-momentum projection method... We develop a relativistic nuclear structure model, relativistic consistent angular-momentum projected shell-model (RECAPS), which combines the relativistic mean-field theory with the angular-momentum projection method. In this new model, nuclear ground-state properties are first calculated consistently using relativistic mean-field (RMF) theory. Then angular momentum projection method is used to project out states with good angular momentum from a few important configurations. By diagonalizing the hamiltonian, the energy levels and wave functions are obtained. This model is a new attempt for the understanding of nuclear structure of normal nuclei and for the prediction of nuclear properties of nuclei far from stability. In this paper, we will describe the treatment of the relativistic mean field. A computer code, RECAPS-RMF, is developed. It solves the relativistic mean field with axial-symmetric deformation in the spherical harmonic oscillator basis. Comparisons between our calculations and existing relativistic mean-field calculations are made to test the model. These include the ground-state properties of spherical nuclei <SUP>16</SUP>O and <SUP>208</SUP>Pb, the deformed nucleus <SUP>20</SUP>Ne. Good agreement is obtained. 展开更多
关键词 relativistic consistent angular-momentum projected shell-model relativistic mean field projected shell model PECAPS-RMF
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Novel similarity measures for face representation based on local binary pattern
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作者 祝世虎 封举富 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第2期223-226,共4页
The successful face recognition based on local binary pattern(LBP)relies on the effective extraction of LBP features and the inferring of similarity between the extracted features.In this paper,we focus on the latter ... The successful face recognition based on local binary pattern(LBP)relies on the effective extraction of LBP features and the inferring of similarity between the extracted features.In this paper,we focus on the latter and propose two novel similarity measures for the local matching methods and the holistic matching methods respectively.One is Earth Mover's Distance with Hamming and Lp ground distance(EMD-HammingLp),which is a cross-bin dissimilarity measure for LBP histograms.The other is IMage Hamming Distance(IMHD),which is a dissimilarity measure for the whole LBP images.Experiments on FERET database show that the proposed two similarity measures outperform the state-of-the-art Chi-square similarity measure for extraction of LBP features. 展开更多
关键词 similarity measurement local binary pattern Earth Mover's Distance IMage Euclidean Distance
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High-Speed Geometric Quantum Computation with Trapped Thermal Ions via Vibrational Mode Decay
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作者 陈昌永 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期275-281,共7页
We utilize the general displacement operator proposed recently [C.Y. Chen, et al., Phys. Rev. A 74 (2006) 032328] to investigate a high-speed geometric quantum computation via vibrational mode decay of two trapped t... We utilize the general displacement operator proposed recently [C.Y. Chen, et al., Phys. Rev. A 74 (2006) 032328] to investigate a high-speed geometric quantum computation via vibrational mode decay of two trapped thermal ions. We find that, under some special conditions, the geometric phase gating is somewhat faster in the heating case than in the ideal case. We also investigate analytically the influence from the vibrational mode heating on the fidelity and the success probability of the implementation. 展开更多
关键词 geometric gate disspation collective motion decay
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Entanglement and Energy for Vibrationally Localized States in Molecule CS2
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作者 Zi-xin Yang Xing Shen Xi-wen Hou 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第3期295-298,I0001,共5页
The dynamics of quantum entanglement described by the yon Neumann entropy is studied for the localized states of Fermi-resonance coupling vibrations in molecule CS2, where the interacting energy between the stretching... The dynamics of quantum entanglement described by the yon Neumann entropy is studied for the localized states of Fermi-resonance coupling vibrations in molecule CS2, where the interacting energy between the stretching and the bending modes is considered to establish a connection between entanglement and energy. It is shown that entanglement reveals dominant anti-correlation with the interacting energy for the stretch-localized state, while that exhibits dominantly positive correlation for the bend-localized state. The entanglement and the energy for the dislocalized states are discussed as well. Those are useful for molecular quantum computing and quantum information in high dimensional states. 展开更多
关键词 ENTANGLEMENT Quantum entropy Vibrational analysis
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Quantum entanglement of the binomial field interacting with a cascade three-level atom beyond the rotating wave approximation 被引量:6
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作者 PEN XueZao CONG HongLu +1 位作者 WANG XuWen XIA JianPing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第9期1625-1630,共6页
In this paper, the quantum entanglement between a single mode binomial field and a cascade three-level atom is calculated mechanically without the rotating wave approximation. The numerical results indicate that the q... In this paper, the quantum entanglement between a single mode binomial field and a cascade three-level atom is calculated mechanically without the rotating wave approximation. The numerical results indicate that the quantum entanglement at the first few periods is reduced notably due to the fact that the atom is initially in the superposition state. With increasing field parameter 17, the period of the entanglement evolution becomes obvious and the quantum decoherence phenomenon emerges in a short time. 展开更多
关键词 binomial state field quantum entanglement field entropy
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