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Combination of Model-based Observer and Support Vector Machines for Fault Detection of Wind Turbines 被引量:10
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作者 Nassim Laouti Sami Othman +1 位作者 Mazen Alamir Nida Sheibat-Othman 《International Journal of Automation and computing》 EI CSCD 2014年第3期274-287,共14页
Support vector machines and a Kalman-like observer are used for fault detection and isolation in a variable speed horizontalaxis wind turbine composed of three blades and a full converter. The support vector approach ... Support vector machines and a Kalman-like observer are used for fault detection and isolation in a variable speed horizontalaxis wind turbine composed of three blades and a full converter. The support vector approach is data-based and is therefore robust to process knowledge. It is based on structural risk minimization which enhances generalization even with small training data set and it allows for process nonlinearity by using flexible kernels. In this work, a radial basis function is used as the kernel. Different parts of the process are investigated including actuators and sensors faults. With duplicated sensors, sensor faults in blade pitch positions,generator and rotor speeds can be detected. Faults of type stuck measurements can be detected in 2 sampling periods. The detection time of offset/scaled measurements depends on the severity of the fault and on the process dynamics when the fault occurs. The converter torque actuator fault can be detected within 2 sampling periods. Faults in the actuators of the pitch systems represents a higher difficulty for fault detection which is due to the fact that such faults only affect the transitory state(which is very fast) but not the final stationary state. Therefore, two methods are considered and compared for fault detection and isolation of this fault: support vector machines and a Kalman-like observer. Advantages and disadvantages of each method are discussed. On one hand, support vector machines training of transitory states would require a big amount of data in different situations, but the fault detection and isolation results are robust to variations in the input/operating point. On the other hand, the observer is model-based, and therefore does not require training, and it allows identification of the fault level, which is interesting for fault reconfiguration. But the observability of the system is ensured under specific conditions, related to the dynamics of the inputs and outputs. The whole fault detection and isolation scheme is evaluated using a wind turbine benchmark with a real sequence of wind speed. 展开更多
关键词 Fault detection and isolation wind turbine Kalman-like observer support vector machines data-based classification
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A Space Vector PWM Scheme for Multilevel Inverters Based on Two-Level Space Vector PWM 被引量:1
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《变频器世界》 2006年第12期26-27,共2页
Ⅰ. INTRODUCTION MULTILEVEL inverters are increasingly being used in high-power medium voltage applications due to their superior performance compared to two-level inverters, such as lower common-mode voltage, lower d... Ⅰ. INTRODUCTION MULTILEVEL inverters are increasingly being used in high-power medium voltage applications due to their superior performance compared to two-level inverters, such as lower common-mode voltage, lower dv/dt, lower harmonics in output voltage and current, and reduced voltage on the power switches. 展开更多
关键词 A Space vector PWM Scheme for Multilevel Inverters based on Two-Level Space vector PWM In
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A SYSTEM IDENTIFICATION METHOD USING VECTOR SPACE BASE FUNCTION
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作者 Lu Ziyi Yang Luxi He Zhenva(DSP Lab., Southeast University, Nanjing 210096) 《Journal of Electronics(China)》 1999年第2期146-151,共6页
This paper presents a new system identification approach using vector space base functions, and proposes two network structures based on Gamma sequence and Laguerre sequence. After analyzing and comparing these struct... This paper presents a new system identification approach using vector space base functions, and proposes two network structures based on Gamma sequence and Laguerre sequence. After analyzing and comparing these structures in detail, some simulation results to demonstrate the conclusions are given. 展开更多
关键词 System identification vector SPACE base FUNCTIONS Adaptive FILTER
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Multimode Process Monitoring Based on the Density-Based Support Vector Data Description
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作者 郭红杰 王帆 +2 位作者 宋冰 侍洪波 谭帅 《Journal of Donghua University(English Edition)》 EI CAS 2017年第3期342-348,共7页
Complex industry processes often need multiple operation modes to meet the change of production conditions. In the same mode,there are discrete samples belonging to this mode. Therefore,it is important to consider the... Complex industry processes often need multiple operation modes to meet the change of production conditions. In the same mode,there are discrete samples belonging to this mode. Therefore,it is important to consider the samples which are sparse in the mode.To solve this issue,a new approach called density-based support vector data description( DBSVDD) is proposed. In this article,an algorithm using Gaussian mixture model( GMM) with the DBSVDD technique is proposed for process monitoring. The GMM method is used to obtain the center of each mode and determine the number of the modes. Considering the complexity of the data distribution and discrete samples in monitoring process,the DBSVDD is utilized for process monitoring. Finally,the validity and effectiveness of the DBSVDD method are illustrated through the Tennessee Eastman( TE) process. 展开更多
关键词 Eastman Tennessee sparse utilized illustrated kernel Bayesian charts validity false
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Some Group Runs Based Multivariate Control Charts for Monitoring the Process Mean Vector
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作者 Mukund Parasharam Gadre Vikas Chintaman Kakade 《Open Journal of Statistics》 2016年第6期1098-1109,共13页
In this article, we propose two control charts namely, the “Multivariate Group Runs’ (MV-GR-M)” and the “Multivariate Modified Group Runs’ (MV-MGR-M)” control charts, based on the multivariate normal processes, ... In this article, we propose two control charts namely, the “Multivariate Group Runs’ (MV-GR-M)” and the “Multivariate Modified Group Runs’ (MV-MGR-M)” control charts, based on the multivariate normal processes, for monitoring the process mean vector. Methods to obtain the design parameters and operations of these control charts are discussed. Performances of the proposed charts are compared with some existing control charts. It is verified that, the proposed charts give a significant reduction in the out-of-control “Average Time to Signal” (ATS) in the zero state, as well in the steady state compared to the Hotelling’s T2 and the synthetic T2 control charts. 展开更多
关键词 Some Group Runs based Multivariate Control Charts for Monitoring the Process Mean vector
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Research of the Unity Theory Between Three-level Space Vector and Carrier-based PWM Modulation Strategy 被引量:28
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作者 CHEN Juan HE Yingjie WANG Xinyu LIU Jinjun 《中国电机工程学报》 EI CSCD 北大核心 2013年第9期I0010-I0010,共1页
两电平空间矢量脉宽调制(space vector pulse widthmodulation,SVPWM)与正弦脉宽调制(sinusoidal pulse widthmodulation,SPWM)存有一定的本质关系,对于三电平,在常见的8段式SVPWM序列中可以证明,SVPWM与SPWM本质上也存在某种统一... 两电平空间矢量脉宽调制(space vector pulse widthmodulation,SVPWM)与正弦脉宽调制(sinusoidal pulse widthmodulation,SPWM)存有一定的本质关系,对于三电平,在常见的8段式SVPWM序列中可以证明,SVPWM与SPWM本质上也存在某种统一。实际的SVPWM调制中,由于要考虑中点电压平衡、减少谐波等其它性能问题,一般会利用开关冗余状态得到8段以上的开关调制序列。目前的文献中还未曾有对这些情况进行统一性地验证,因此三电平SVPWM与SPWM的统一理论存在一定的不足。研究发现,可通过严格地理论推导将传统意义上的调制波分解为2个子调制波,再进行SPWM调制,可以得到与SVPWM完全吻合的序列。该文在此方法基础上深入研究了8段以上(10、12、14段)的SVPWM调制序列与SPWM的统一。经过严格地理论推导,成功实现了含任意段数的SVPWM序列与SPWM的统一。仿真结果证明了该理论的正确性。 展开更多
关键词 三电平逆变器 SVPWM 调制策略 统一理论 载波 矢量和 空间 研究人员
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Corner-Based Image Alignment using Pyramid Structure with Gradient Vector Similarity
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作者 Chin-Sheng Chen Kang-Yi Peng +1 位作者 Chien-Liang Huang Chun-Wei Yeh 《Journal of Signal and Information Processing》 2013年第3期114-119,共6页
This paper presents a corner-based image alignment algorithm based on the procedures of corner-based template matching and geometric parameter estimation. This algorithm consists of two stages: 1) training phase, and ... This paper presents a corner-based image alignment algorithm based on the procedures of corner-based template matching and geometric parameter estimation. This algorithm consists of two stages: 1) training phase, and 2) matching phase. In the training phase, a corner detection algorithm is used to extract the corners. These corners are then used to build the pyramid images. In the matching phase, the corners are obtained using the same corner detection algorithm. The similarity measure is then determined by the differences of gradient vector between the corners obtained in the template image and the inspection image, respectively. A parabolic function is further applied to evaluate the geometric relationship between the template and the inspection images. Results show that the corner-based template matching outperforms the original edge-based template matching in efficiency, and both of them are robust against non-liner light changes. The accuracy and precision of the corner-based image alignment are competitive to that of edge-based image alignment under the same environment. In practice, the proposed algorithm demonstrates its precision, efficiency and robustness in image alignment for real world applications. 展开更多
关键词 Corner-based Image Alignment CORNER Detection Edge-based TEMPLATE Matching Gradient vector
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A C-Based Variable Length and Vector Pipeline Architecture Design Methodology and Its Application
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作者 Takashi Kambe Nobuyuki Araki 《Circuits and Systems》 2012年第1期10-16,共7页
The size and performance of a System LSI depend heavily on the architecture which is chosen. As a result, the architecture design phase is one of the most important steps in the System LSI development process and is c... The size and performance of a System LSI depend heavily on the architecture which is chosen. As a result, the architecture design phase is one of the most important steps in the System LSI development process and is critical to the commercial success of a device. In this paper, we propose a C-based variable length and vector pipeline (VVP) architecture design methodology and apply it to the design of the output probability computation circuit for a speech recognition system. VVP processing accelerated by loop optimization, memory access methods, and application-specific cir- cuit design was implemented to calculate the Hidden Markov Model (HMM) output probability at high speed and its performance is evaluated. It is shown that designers can explore a wide range of design choices and generate complex circuits in a short time by using a C-based pipeline architecture design method. 展开更多
关键词 Variable Length and vector PIPELINE Architecture C-based Design System LSI SPEECH Recognition
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Reliability-based multidisciplinary design optimization using incremental shifting vector strategy and its application in electronic product design 被引量:10
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作者 Z.L.Huang Y.S.Zhou +2 位作者 C.Jiang J.Zheng X.Han 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2018年第2期285-302,共18页
Use of multidisciplinary analysis in reliabilitybased design optimization(RBDO) results in the emergence of the important method of reliability-based multidisciplinary design optimization(RBMDO). To enhance the effici... Use of multidisciplinary analysis in reliabilitybased design optimization(RBDO) results in the emergence of the important method of reliability-based multidisciplinary design optimization(RBMDO). To enhance the efficiency and convergence of the overall solution process,a decoupling algorithm for RBMDO is proposed herein.Firstly, to decouple the multidisciplinary analysis using the individual disciplinary feasible(IDF) approach, the RBMDO is converted into a conventional form of RBDO. Secondly,the incremental shifting vector(ISV) strategy is adopted to decouple the nested optimization of RBDO into a sequential iteration process composed of design optimization and reliability analysis, thereby improving the efficiency significantly. Finally, the proposed RBMDO method is applied to the design of two actual electronic products: an aerial camera and a car pad. For these two applications, two RBMDO models are created, each containing several finite element models(FEMs) and relatively strong coupling between the involved disciplines. The computational results demonstrate the effectiveness of the proposed method. 展开更多
关键词 Reliability-based design optimization(RBDO) Multidisciplinary design optimization(MDO) Incremental shifting vector(ISV) Decoupling algorithm Electronic product
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虚拟场景中基于Motion Vector的人群图像绘制算法
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作者 霍奕 王喜年 +3 位作者 张瑜 陈敬利 马海滨 张鹏飞 《计算机工程与应用》 CSCD 北大核心 2009年第23期173-175,199,共4页
针对虚拟场景中大规模人群图像绘制时由于采集图像数量有限,在视点连续变化时出现跳变的问题,提出了一种基于Motion Vector的图像绘制算法,该算法通过移动原始图像的像素位置生成相邻视点位置的图像,使得各个离散采样之间能够连续过渡,... 针对虚拟场景中大规模人群图像绘制时由于采集图像数量有限,在视点连续变化时出现跳变的问题,提出了一种基于Motion Vector的图像绘制算法,该算法通过移动原始图像的像素位置生成相邻视点位置的图像,使得各个离散采样之间能够连续过渡,很好地解决了由于采样不足而引起的跳变问题,同时保证了绘制系统的实时性,实验结果验证了该算法的有效性。 展开更多
关键词 虚拟现实 人群仿真 基于图像的绘制 运动矢量
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An E-Commerce Recommender System Based on Content-Based Filtering 被引量:3
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作者 HE Weihong CAO Yi 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1091-1096,共6页
Content-based filtering E-commerce recommender system was discussed fully in this paper. Users' unique features can be explored by means of vector space model firstly. Then based on the qualitative value of products ... Content-based filtering E-commerce recommender system was discussed fully in this paper. Users' unique features can be explored by means of vector space model firstly. Then based on the qualitative value of products informa tion, the recommender lists were obtained. Since the system can adapt to the users' feedback automatically, its performance were enhanced comprehensively. Finally the evaluation of the system and the experimental results were presented. 展开更多
关键词 E-COMMERCE recommender system personalized recommendation content-based filtering vector Spatial Model(VSM)
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Image Processing on Geological Data in Vector Format and Multi-Source Spatial Data Fusion
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作者 Liu Xing Hu Guangdao Qiu Yubao Faculty of Earth Resources, China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期278-282,共5页
The geological data are constructed in vector format in geographical information system (GIS) while other data such as remote sensing images, geographical data and geochemical data are saved in raster ones. This paper... The geological data are constructed in vector format in geographical information system (GIS) while other data such as remote sensing images, geographical data and geochemical data are saved in raster ones. This paper converts the vector data into 8 bit images according to their importance to mineralization each by programming. We can communicate the geological meaning with the raster images by this method. The paper also fuses geographical data and geochemical data with the programmed strata data. The result shows that image fusion can express different intensities effectively and visualize the structure characters in 2 dimensions. Furthermore, it also can produce optimized information from multi-source data and express them more directly. 展开更多
关键词 geological data GIS-based vector data conversion image processing multi-source data fusion
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电机气隙磁场调制统一理论研究进展与展望 被引量:8
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作者 程明 马钲洲 +2 位作者 花为 汪波 王政 《中国电机工程学报》 北大核心 2025年第4期1220-1236,I0001,共18页
电机气隙磁场调制统一理论于2017年由作者团队提出以来,便因在电机原理分析、性能计算和拓扑创新方面的优势,成为行业内的热点研究方向,经过多年的深入研究,在电机气隙磁场调制机理、气隙磁场调制数学表征方法等方面取得了多项原创性成... 电机气隙磁场调制统一理论于2017年由作者团队提出以来,便因在电机原理分析、性能计算和拓扑创新方面的优势,成为行业内的热点研究方向,经过多年的深入研究,在电机气隙磁场调制机理、气隙磁场调制数学表征方法等方面取得了多项原创性成果。该文从理论、技术和应用3个层面综述电机气隙磁场调制理论的最新研究进展,包括:提出磁感、磁容调制器,将磁场调制模态拓展为频率调制、幅值调制和相位调制,提出“基波+谐波”的多工作波电机设计思想等,厘清电机气隙磁场调制理论与传统电机理论的关系等。最后,对气隙磁场调制统一理论未来研究与发展方向进行展望。 展开更多
关键词 电机理论 磁场调制理论 谐波利用 多工作波电机 矢量磁路理论 磁感 电能
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A Creative Approach to Reducing Ambiguity in Scenario-based Software Architecture Analysis 被引量:1
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作者 Xi-Wen Wu Chen Li +1 位作者 Xuan Wang Hong-Ji Yang 《International Journal of Automation and computing》 EI CSCD 2019年第2期248-260,共13页
In software engineering, a scenario describes an anticipated usage of a software system. As scenarios are useful to understand the requirements and functionalities of a software system, the scenario-based analysis is ... In software engineering, a scenario describes an anticipated usage of a software system. As scenarios are useful to understand the requirements and functionalities of a software system, the scenario-based analysis is widely used in various tasks, especially in the design stage of software architectures. Although researchers have proposed various scenario-based approaches to analyse software architecture, there are still limitations in this research field, and a key limitation is that scenarios are typically not formally defined and thus may contain ambiguities. As these ambiguities may lead to defects, it is desirable to reduce them as many as possible. In order to reduce ambiguity in scenario-based software architecture analysis, this paper introduces a creative computing approach to scenario-based software requirements analysis. Our work expands this idea in three directions. Firstly, we extend an architecture description language(ADL)-based language – Breeze/ADL to model the software architecture. Secondly, we use a creative rule – combinational rule(CR) to combine the vector clock algorithm for reducing the ambiguities in modelling scenarios. Then, another creative rule – transformational rule(TR) is employed to help to transform our Breeze/ADL model to a popular model – unified modelling language(UML) model. We implement our approach as a plugin of Breeze, and illustrate a running example of modelling a poetry to music system in our case study.Our results show the proposed creative approach is able to reduce ambiguities of the software architecture in practice. 展开更多
关键词 Creative computing vector clock algorithm scenario-based analysis of SOFTWARE ARCHITECTURE sequence diagram Breeze/ ARCHITECTURE description language (ADL)
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Key Technology in Developing Web-Based Engineering Drawing CAI Software 被引量:7
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作者 Feng Kaiping Zuo Zongyi (Guangdong University of Technology, Guangzhou 510090, China) Wen Junwen (Physics Department, Zhanjiang Normal College Jinhua 316101, China) Miscillaneous 《Computer Aided Drafting,Design and Manufacturing》 2000年第2期89-95,共7页
Key techniques to improve the quality of developing Web-based engineering drawing CAI software are discussed and some experience in applying commercial tools for generating vector drawing, concise representation of 3D... Key techniques to improve the quality of developing Web-based engineering drawing CAI software are discussed and some experience in applying commercial tools for generating vector drawing, concise representation of 3D solids, real-time interactive animation, data management etc. is illustrated. A Web-based Engineering Drawing CAI software 'Solid Projection' has been implemented by using these techniques. 展开更多
关键词 Web-based education vector drawing true 3D model real-time interaction Vh
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Monitoring models for base flow effect and daily variation of dam seepage elements considering time lag effect 被引量:14
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作者 Shao-wei Wang Ying-li Xu +1 位作者 Chong-shi Gu Teng-fei Bao 《Water Science and Engineering》 EI CAS CSCD 2018年第4期344-354,共11页
Affected by external environmental factors and evolution of dam performance, dam seepage behavior shows nonlinear time-varying characteristics. In this study, to predict and evaluate the long-term development trend an... Affected by external environmental factors and evolution of dam performance, dam seepage behavior shows nonlinear time-varying characteristics. In this study, to predict and evaluate the long-term development trend and short-term fluctuation of the dam seepage behavior, two monitoring models were developed, one for the base flow effect and one for daily variation of dam seepage elements. In the first model, to avoid the influence of the time lag effect on the evaluation of seepage variation with the time effect component of seepage elements, the base values of the seepage element and the reservoir water level were extracted using the wavelet multi-resolution analysis method, and the time effect component was separated by the established base flow effect monitoring model. For the development of the daily variation monitoring model for dam seepage elements, all the previous factors, of which the measured time series prior to the dam seepage element monitoring time may have certain influence on the monitored results, were considered. Those factors that were positively correlated with the analyzed seepage element were initially considered to be the support vector machine(SVM) model input factors, and then the SVM kernel function-based sensitivity analysis was performed to optimize the input factor set and establish the optimized daily variation SVM model. The efficiency and rationality of the two models were verified by case studies of the water level of two piezometric tubes buried under the slope of a concrete gravity dam.Sensitivity analysis of the optimized SVM model shows that the influences of the daily variation of the upstream reservoir water level and rainfall on the daily variation of piezometric tube water level are processes subject to normal distribution. 展开更多
关键词 Dam seepage monitoring model Time lag effect Support vector machine(SVM) Sensitivity analysis base flow Daily variation Piezometric tube water level
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Identification of Question and Non-Question Segments in Arabic Monologues Using Prosodic Features: Novel Type-2 Fuzzy Logic and Sensitivity-Based Linear Learning Approaches
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作者 Sunday Olusanya Olatunji Lahouari Cheded +1 位作者 Wasfi G. Al-Khatib Omair Khan 《Journal of Intelligent Learning Systems and Applications》 2013年第3期165-175,共11页
In this paper, we extend our previous study of addressing the important problem of automatically identifying question and non-question segments in Arabic monologues using prosodic features. We propose here two novel c... In this paper, we extend our previous study of addressing the important problem of automatically identifying question and non-question segments in Arabic monologues using prosodic features. We propose here two novel classification approaches to this problem: one based on the use of the powerful type-2 fuzzy logic systems (type-2 FLS) and the other on the use of the discriminative sensitivity-based linear learning method (SBLLM). The use of prosodic features has been used in a plethora of practical applications, including speech-related applications, such as speaker and word recognition, emotion and accent identification, topic and sentence segmentation, and text-to-speech applications. In this paper, we continue to specifically focus on the Arabic language, as other languages have received a lot of attention in this regard. Moreover, we aim to improve the performance of our previously-used techniques, of which the support vector machine (SVM) method was the best performing, by applying the two above-mentioned powerful classification approaches. The recorded continuous speech is first segmented into sentences using both energy and time duration parameters. The prosodic features are then extracted from each sentence and fed into each of the two proposed classifiers so as to classify each sentence as a Question or a Non-Question sentence. Our extensive simulation work, based on a moderately-sized database, showed the two proposed classifiers outperform SVM in all of the experiments carried out, with the type-2 FLS classifier consistently exhibiting the best performance, because of its ability to handle all forms of uncertainties. 展开更多
关键词 ARABIC Monologues Prosodic Features Type-2 FUZZY LOGIC Systems Sensitivity based LINEAR LearningMethod Support vector Machines
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Research on Vehicle Tracking Method Based on YOLOv8 and Adaptive Kalman Filtering: Integrating SVM Dynamic Selection and Error Feedback Mechanism
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作者 Liping Zheng Hao Gou +1 位作者 Kaiwen Xiao Moran Qiu 《Open Journal of Applied Sciences》 2024年第12期3569-3588,共20页
Vehicle tracking plays a crucial role in intelligent transportation, autonomous driving, and video surveillance. However, challenges such as occlusion, multi-target interference, and nonlinear motion in dynamic scenar... Vehicle tracking plays a crucial role in intelligent transportation, autonomous driving, and video surveillance. However, challenges such as occlusion, multi-target interference, and nonlinear motion in dynamic scenarios make tracking accuracy and stability a focus of ongoing research. This paper proposes an integrated method combining YOLOv8 object detection with adaptive Kalman filtering. The approach employs a support vector machine (SVM) to dynamically select the optimal filter (including standard Kalman filter, extended Kalman filter, and unscented Kalman filter), enhancing the system’s adaptability to different motion patterns. Additionally, an error feedback mechanism is incorporated to dynamically adjust filter parameters, further improving responsiveness to sudden events. Experimental results on the KITTI and UA-DETRAC datasets demonstrate that the proposed method significantly improves detection accuracy (mAP@0.5 increased by approximately 3%), tracking accuracy (MOTA improved by 5%), and system robustness, providing an efficient solution for vehicle tracking in complex environments. 展开更多
关键词 Multi-Target Tracking YOLOv8-based Detection Adaptive Filtering Support vector Machine Error Feedback Mechanism
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Formability of Rare Earth-Containing Solid Solution Based on Compounds with Scheelite-Type Structure
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作者 Luo Yunyun Bao Xinhua +2 位作者 Lu Wencong Chen Nianyi Xia Yiben 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第4期I0010-I0010,共1页
The regularities of the solid solutions between the scheelite-type compounds and rare earth molybdates or tungstates were investigated by the atomic parameter-support vector machine method and the intelligent database... The regularities of the solid solutions between the scheelite-type compounds and rare earth molybdates or tungstates were investigated by the atomic parameter-support vector machine method and the intelligent database of phase diagrams of molten salt systems. The crystal structure of scheelite-type compounds having M^1M^′Ⅲ (XO4)2(X = Mo, W) as common formula and the formability of the continuous solid solution between these compounds and rare earth molybdates or tungstates were also investigated. Besides, the cell constants of these compounds can be calculated by some semi-empirical equations. Based on the obtained relationships, the results of computerized prediction of the solid solubility of T1Pr (MoO4)2-Pr2 (MoO4)3 system have good agreement with experimental results. 展开更多
关键词 scheelite-type structure solid solution support vector machine (SVM) intelligent data base of phase diagrams rare earth materials design
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Content-based image retrieval applied to BI-RADS tissue classification in screening mammography 被引量:1
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作者 Júlia Epischina Engrácia de Oliveira Arnaldo de Albuquerque Araújo Thomas M Deserno 《World Journal of Radiology》 CAS 2011年第1期24-31,共8页
AIM:To present a content-based image retrieval(CBIR) system that supports the classification of breast tissue density and can be used in the processing chain to adapt parameters for lesion segmentation and classificat... AIM:To present a content-based image retrieval(CBIR) system that supports the classification of breast tissue density and can be used in the processing chain to adapt parameters for lesion segmentation and classification.METHODS:Breast density is characterized by image texture using singular value decomposition(SVD) and histograms.Pattern similarity is computed by a support vector machine(SVM) to separate the four BI-RADS tissue categories.The crucial number of remaining singular values is varied(SVD),and linear,radial,and polynomial kernels are investigated(SVM).The system is supported by a large reference database for training and evaluation.Experiments are based on 5-fold cross validation.RESULTS:Adopted from DDSM,MIAS,LLNL,and RWTH datasets,the reference database is composed of over 10000 various mammograms with unified and reliable ground truth.An average precision of 82.14% is obtained using 25 singular values(SVD),polynomial kernel and the one-against-one(SVM).CONCLUSION:Breast density characterization using SVD allied with SVM for image retrieval enable the development of a CBIR system that can effectively aid radiologists in their diagnosis. 展开更多
关键词 COMPUTER-AIDED diagnosis CONTENT-baseD IMAGE retrieval IMAGE processing Screening MAMMOGRAPHY SINGULAR value decomposition Support vector machine
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