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基于复杂类型数据的发现特征子空间模型(DFSSM)的研究 被引量:10
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作者 杨炳儒 唐菁 《中国工程科学》 2003年第1期56-61,68,共7页
探讨围绕知识发现领域中较为宏观、较为重大的问题。首先 ,根据复杂类型数据 (包括Web数据、多媒体数据、空间数据、时间序列数据等 )所具有的非线性动力学性质和特征 ,采用模式 (定义为Hilbert空间中的矢量 )来定量地表征复杂类型数据... 探讨围绕知识发现领域中较为宏观、较为重大的问题。首先 ,根据复杂类型数据 (包括Web数据、多媒体数据、空间数据、时间序列数据等 )所具有的非线性动力学性质和特征 ,采用模式 (定义为Hilbert空间中的矢量 )来定量地表征复杂类型数据的多变性及具有的不确定状态和行为 ,并用模式的变化来刻画其整体知识发现过程的发展和演变规律 ;其次 ,以知识发现系统内在机理的研究为基础 ,构造了复杂类型数据知识发现系统的总体结构模型———发现特征子空间模型DFSSM ;最后 ,用基于Web的文本挖掘系统和基于图像信息 (气象云图 )的知识发现系统作为实例进行了验证 ,结果表明DFSSM方法对于非结构化的文本数据及图像数据类型的知识发现过程具有指导性作用。因此 ,该结构模型具有较好的实用性与普适性 。 展开更多
关键词 发现特征空间模型 复杂类型数据 数据挖掘 文本挖掘 知识发现系统 结构化数据
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对光照变化鲁棒的多特征动态提取跟踪算法
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作者 李琳 余胜生 《武汉理工大学学报(信息与管理工程版)》 CAS 2014年第4期460-464,共5页
针对视觉跟踪算法光照自适应能力差的问题,提出了一种对光照变化鲁棒的多特征动态提取跟踪算法。该算法采用高效克服光照影响的特征提取方法,颜色子模型采用模糊直方图方法获取,在同态滤波基础上建立边缘子模型,运动子模型采用改进的三... 针对视觉跟踪算法光照自适应能力差的问题,提出了一种对光照变化鲁棒的多特征动态提取跟踪算法。该算法采用高效克服光照影响的特征提取方法,颜色子模型采用模糊直方图方法获取,在同态滤波基础上建立边缘子模型,运动子模型采用改进的三帧差分法提取。该算法还定义了一个新的特征融合模型,把多种互补的观测子模型动态融合,增强了观测模型的准确性,合理量化特征的可靠性使跟踪更稳定。同时采用改进的粒子重采样方法提高了跟踪准确度。实验结果表明,该算法能有效地避免光照变化对跟踪的影响,具有较好的鲁棒性。 展开更多
关键词 光照鲁棒 特征子模型 融合建模 重采样策略
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基于DCSSM的文本特征提取及文本挖掘研究 被引量:2
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作者 梁开健 《自动化技术与应用》 2005年第5期54-56,共3页
提出了用模式作为复杂类型数据的知识表示方法,结合结构化数据挖掘给出了基于复杂类型数据知识发现的结构模型——发现特征子空间模型DCSSM。在此基础上讨论了文本特征提取及文本挖掘的方法。
关键词 模式 发现特征空间模型 文本特征提取
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基于DFSSM的WEB文本挖掘过程的研究和应用
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作者 康迎曦 《湖南工程学院学报(自然科学版)》 2013年第3期44-46,共3页
给出DFSSM的一般性描述,通过对特征词选取方法的介绍和文本表示方法的分析,进而给出该模型下文本挖掘中具体过程,最后结合项目背景分析了DFSSM模型下文本挖掘的过程,从而设计出高效的文本挖掘工具.
关键词 文本挖掘 发现特征空间模型 语义理解
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A robust feature extraction approach based on an auditory model for classification of speech and expressiveness 被引量:5
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作者 孙颖 V.Werner 张雪英 《Journal of Central South University》 SCIE EI CAS 2012年第2期504-510,共7页
Based on an auditory model, the zero-crossings with maximal Teager energy operator (ZCMT) feature extraction approach was described, and then applied to speech and emotion recognition. Three kinds of experiments were ... Based on an auditory model, the zero-crossings with maximal Teager energy operator (ZCMT) feature extraction approach was described, and then applied to speech and emotion recognition. Three kinds of experiments were carried out. The first kind consists of isolated word recognition experiments in neutral (non-emotional) speech. The results show that the ZCMT approach effectively improves the recognition accuracy by 3.47% in average compared with the Teager energy operator (TEO). Thus, ZCMT feature can be considered as a noise-robust feature for speech recognition. The second kind consists of mono-lingual emotion recognition experiments by using the Taiyuan University of Technology (TYUT) and the Berlin databases. As the average recognition rate of ZCMT approach is 82.19%, the results indicate that the ZCMT features can characterize speech emotions in an effective way. The third kind consists of cross-lingual experiments with three languages. As the accuracy of ZCMT approach only reduced by 1.45%, the results indicate that the ZCMT features can characterize emotions in a language independent way. 展开更多
关键词 speech recognition emotion recognition zero-crossings Teager energy operator speech database
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Analysis of nonlinearities and effects in direct drive electro-hydraulic position servo system 被引量:2
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作者 王洪杰 季天晶 +1 位作者 毛新涛 刘全忠 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第1期6-10,共5页
The direct drive electro-hydraulic servo system is a new approach hydraulic system. It is much smaller and easier controlled than traditional systems and is a perfect energy saver. This paper will briefly introduce th... The direct drive electro-hydraulic servo system is a new approach hydraulic system. It is much smaller and easier controlled than traditional systems and is a perfect energy saver. This paper will briefly introduce the popular nonlinearities in the electro-hydraulic system and analyse the effect of nonlinearities in direct drive electro-hydraulic position servo system by means of simulation research. Some valuable conclusions are given. 展开更多
关键词 direct drive electro-hydraulic system NONLINEARITIES EFFECT
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An Explanation of a Phenomenon in Relativistic Heavy-Ion Collisions
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作者 陈小凡 杨学栋 +2 位作者 陈志来 孙芳魁 苏润洲 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第4期640-642,共3页
The multi-source pion interferometry in relativistic heavy-ion collisions is presented and two-source models for hadron gas and hadron gas plus quark-gluon plasma are proposed. The models can resolve the HBT puzzle. F... The multi-source pion interferometry in relativistic heavy-ion collisions is presented and two-source models for hadron gas and hadron gas plus quark-gluon plasma are proposed. The models can resolve the HBT puzzle. For the same q and different direction of q, the two-pion correlation functions show characteristic oscillation behaviors, which may be used to distinguish the two-source models. Our research also showes that the multi-source pion correlations can resolve the HBT puzzle. 展开更多
关键词 multi-source pion interferometry HBT puzzle relativistic heavy-ion collisions
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Causal Relationship Model of Firm Characteristics Factors and Good Cooperate Governance Affecting the Performance of the Companies Listed on the Stock Exchange of Thailand
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作者 Senee Puangyanee Supisam Bhakdinarinath 《Management Studies》 2017年第6期589-597,共9页
The objective of this research was to develop the causal relationship model of firm characteristics factors and good corporate governance affecting the performance of the companies listed on the Stock Exchange of Thai... The objective of this research was to develop the causal relationship model of firm characteristics factors and good corporate governance affecting the performance of the companies listed on the Stock Exchange of Thailand. The developed model consisted of three latent variables and eight observable variables. The sample of this study was 338 companies listed on the Stock Exchange of Thailand. Data are from annual reports (form-56), annual financial statements and notes to the fmancial statements during the years 2010-2013. The statistics used in this study were descriptive statistics. The causal model was analyzed through a path analysis with LISREL 8.80 Student Edition. The results showed as follows. By testing the consistence of the causal model of finn characteristics (CHA), the assumed model was consistent with empirical data. Based on the statistical test, the Chi-Square was 22.08. The statistical probability (p) was 0.077, the degree of freedom (dO was to 0, 2/2 was 1.58, RMSEA was 0.041, SRMR was 0.037, GFI was 0.98, CFI was 0.99, AGFI was 0.96. The latent variable of firm characteristics (CHA) had directly negative impact on performance (PAL) with a statistical significance level of 0.01. A path coefficient was 0.18. However, CHA variable did not indirectly influence performance (PAL) and it had directly negative impact on good corporate governance (GGN) with a path coefficient of 0.02 without statistical significance level. The latent variable of good corporate governance (GGN) had directly positive impact on the performance (PAL) with a statistical significance level of 0.05, with a path coefficient of 0.18. 展开更多
关键词 ftrm characteristics good corporate governance PERFORMANCE
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Pseudo-invariant Eigen-Operator Method for Solving Field-Intensity-Dependent Jaynes-Cummings Model
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作者 俞挞汐 范洪义 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期257-260,共4页
By using Gumming (JC) model. energy-level gap of this the pseudo invariant eigen-operator method we The pseudo-invariant eigen-operator is found in JC Hamiltonian is derived. This approach seems analyze the field-in... By using Gumming (JC) model. energy-level gap of this the pseudo invariant eigen-operator method we The pseudo-invariant eigen-operator is found in JC Hamiltonian is derived. This approach seems analyze the field-intensity-dependent Jaynes terms of the supersymmetric generators. The concise. 展开更多
关键词 pseudo-invariant eigen-operator energy-level gap Jaymes-Cummings model
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Establishing an Initial Electron Beam Model with Monte Carlo Simulation for a Single 6 MV X-ray Medical Linac Based on Particle Dynamics Characteristics
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作者 ZHAO Hong-bin KONG Xiao-xiao +2 位作者 LI Quan-feng LIN Xiao-qi BAO Shang-lian 《Chinese Journal of Biomedical Engineering(English Edition)》 2009年第2期47-54,66,共9页
Objective:In this study,we try to establish an initial electron beam model by combining Monte Carlo simulation method with particle dynamic calculation(TRSV)for the single 6 MV X-ray accelerating waveguide of BJ-6 med... Objective:In this study,we try to establish an initial electron beam model by combining Monte Carlo simulation method with particle dynamic calculation(TRSV)for the single 6 MV X-ray accelerating waveguide of BJ-6 medical linac.Methods and Materials:1.We adapted the treatment head configuration of BJ-6 medical linac made by Beijing Medical Equipment Institute(BMEI)as the radiation system for this study.2.Use particle dynamics calculation code called TRSV to drive out the initial electron beam parameters of the energy spectrum,the spatial intensity distribution,and the beam incidence angle.3.Analyze the 6 MV X-ray beam characteristics of PDDc,OARc in a water phantom by using Monte Carlo simulation(BEAMnrc,DOSXYZnrc)for a preset of the initial electron beam parameters which have been determined by TRSV,do the comparisons of the measured results of PDDm,OARm in a real water phantom,and then use the deviations of calculated and measured results to slightly modify the initial electron beam model back and forth until the deviations meet the error less than 2%.Results:The deviations between the Monte Carlo simulation results of percentage depth doses at PDDc and off-axis ratios OARc and the measured results of PDDm and OARm in a water phantom were within 2%.Conclusion:When doing the Monte Carlo simulation to determine the parameters of an initial electron beam for a particular medical linac like BJ-6,modifying some parameters based on the particle dynamics calculation code would give some more reasonable and more acceptable results. 展开更多
关键词 initial electron beam model particle dynamic calculation Monte Carlosimulation medical linear accelerator
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The Testing Intelligence System Based on Factor Models and Self-Organizing Feature Maps
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作者 A.S. Panfilova L.S. Kuravsky 《Journal of Mathematics and System Science》 2013年第7期353-358,共6页
Presented is a new testing system based on using the factor models and self-organizing feature maps as well as the method of filtering undesirable environment influence. Testing process is described by the factor mode... Presented is a new testing system based on using the factor models and self-organizing feature maps as well as the method of filtering undesirable environment influence. Testing process is described by the factor model with simplex structure, which represents the influences of genetics and environmental factors on the observed parameters - the answers to the questions of the test subjects in one case and for the time, which is spent on responding to each test question to another. The Monte Carlo method is applied to get sufficient samples for training self-organizing feature maps, which are used to estimate model goodness-of-fit measures and, consequently, ability level. A prototype of the system is implemented using the Raven's Progressive Matrices (Advanced Progressive Matrices) - an intelligence test of abstract reasoning. Elimination of environment influence results is performed by comparing the observed and predicted answers to the test tasks using the Kalman filter, which is adapted to solve the problem. The testing procedure is optimized by reducing the number of tasks using the distribution of measures to belong to different ability levels after performing each test task provided the required level of conclusion reliability is obtained. 展开更多
关键词 Self-organizing feature maps intelligence testing Kalman filter
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Study of the cavity-magnon-polariton transmission line shape 被引量:1
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作者 Michael Harder LiHui Bai +2 位作者 Christophe Match Jesko Sirker CanMing Hu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第11期70-80,共11页
We experimentally and theoretically investigate the microwave transmission line shape of the cavity-magnon-polariton(CMP)created by inserting a low damping magnetic insulator into a high quality 3D microwave cavity. W... We experimentally and theoretically investigate the microwave transmission line shape of the cavity-magnon-polariton(CMP)created by inserting a low damping magnetic insulator into a high quality 3D microwave cavity. While fixed field measurements are found to have the expected Lorentzian characteristic, at fixed frequencies the field swept line shape is in general asymmetric. Such fixed frequency measurements demonstrate that microwave transmission can be used to access magnetic characteristics of the CMP,such as the field line width H. By developing an effective oscillator model of the microwave transmission we show that these line shape features are general characteristics of harmonic coupling. At the same time, at the classical level the underlying physical mechanism of the CMP is electrodynamic phase correlation and a second model based on this principle also accurately reproduces the experimental line shape features. In order to understand the microscopic origin of the effective coupled oscillator model and to allow for future studies of CMP phenomena to extend into the quantum regime, we develop a third, microscopic description,based on a Green's function formalism. Using this method we calculate the transmission spectra and find good agreement with the experimental results. 展开更多
关键词 cavity-magnon-polariton strong-coupling microwave cavity ferromagnetic resonance
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Study of Soil-Water Characteristic Curve Using Microscopic Spherical Particle Model 被引量:22
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作者 YANG Song LU Ting-Hao 《Pedosphere》 SCIE CAS CSCD 2012年第1期103-111,共9页
When variations occur in the water content or dry bulk density of soil,the contact angle hysteresis will affect the soil-water characteristic curve(SWCC).The occurrence of the contact angle hysteresis can be divided i... When variations occur in the water content or dry bulk density of soil,the contact angle hysteresis will affect the soil-water characteristic curve(SWCC).The occurrence of the contact angle hysteresis can be divided into slipping and pinning.It is difficult to determine the effect of pinning existence on SWCC by tests.In this study,the effect of contact angle hysteresis on SWCC was analyzed either in the case of no variations in soil dry bulk density with changes in soil water content or no variations in soil water content with changes in soil dry bulk density.In both cases,soil particles were simplified to the spherical particle model.Based on the geometrically mechanic relationship between the particles and connecting liquid bridges,a physical model for predicting the SWCC was derived from the spherical particle model.Adjusting parameters made the model applicable to various soils,that is,the cohesive soil was considered as micron-sized spherical particles.Through the simulations on SWCC test data of sand,silt,clay,and swelling soil,it was confirmed that the physical model possessed good reliability and practicability.Finally,the analysis of rationality of contact angle was performed based on the basic assumptions of the model. 展开更多
关键词 connecting liquid bridge contact angle hysteresis dry bulk density physical model
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