检索结果-内蒙古大学图书馆

Computing and Information Technology (ICCIT-1441), 2020 International Conference on

作者： Hafaiedh Hajer Saoudi Yahia Benamor Anouar Chrifi-Alaoui Larbi Okba Taouali University of Tunis Higher National School of Engineering of Tunis (ENSIT) Tunis Tunisia Laboratory of Automatic Signal and Image Processing (LARATSI) National School of Engineers of Monastir University of Monastir Monastir Tunisia Laboratory of Control and Energy Management Laboratory (CEMLab) National engineering school of Sfax University of Sfax Sfax Tunisia Verne IUT of Amiens Avenue of Faculties Laboratory of Innovative Technologies of the University of Picardy Jules Amiens France Faculty of Computers and Information Technology University of Tabuk Tabuk Saudi Arabia

ISBN: (数字)9798350353839

ISBN: (纸本)9798350353846

There are several issues with energy quality when wind energy is integrated into electrical networks. This study further classifies these problems, focusing particularly on harmonics and short-term voltage fluctuations resulting from the integration of two types of wind turbines: the first type is the Squirrel Cage Induction Generator (SCIG), and the second type is the Double-Fed Induction Generator (DFIG). Additionally, it explores methods and tools to mitigate these challenges. The article focuses on future opportunities and current trends in improving the integration of Wind Energy Conversion Systems (WECS) into power grids. Through steady-state time series simulations, the study presents case studies examining voltage fluctuations, an important concern for power quality. Using the IEEE 14-bus test, designed to accommodate various operating conditions and wind power penetrations, the study assesses the impact on power quality. These systems feature synchronous generators connected by automated voltage regulators (AVR) to buses 2 and 4.

关键词： Voltage fluctuations Regulators Fluctuations Power quality Time series analysis Synchronous generators Wind turbines Steady-state Voltage control Wind energy conversion

来源：评论

学校读者我要写书评

暂无评论

INTERFERENCE-TOLERANT TIME-DIFFERENCE-OF-ARRIVAL ESTIMATION FOR MODULATED signalS

引用

IEEE TRANSACTIONS ON ACOUSTICS SPEECH AND signal processing 1988年第9期36卷 1385-1395页

作者： GARDNER, WA CHEN, CK Signal and Image Processing Laboratory Department of Electrical Engineering and Computer Science University of California슠Davis Davis CA USA Signal and Image Processing Laboratory Department of Electrical Engineering and Computer Science University of California Davis Davis CA USA

A method for estimation of the difference in the times of arrival of wavefronts of two separate sensors is introduced. The method, called SPECCORR, exploits the spectral correlation property, called spectral coherence, that essentially all modulated signals exhibit to obtain estimates that are highly tolerant to severely corruptive noise and interference. This tolerance is explained theoretically and demonstrated with simulations.< >

关键词： Interference Time difference of arrival Noise measurement Narrowband Autocorrelation Direction of arrival estimation Antenna measurements Design methodology signal design

来源：评论

学校读者我要写书评

暂无评论

signal INTERCEPTION - A UNIFYING THEORETICAL FRAMEWORK FOR FEATURE DETECTION

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 1988年第8期36卷 897-906页

作者： GARDNER, WA Signal and Image Processing Laboratory Department of Electrical Engineering and Computer Science University of California Davis CA USA

The unifying framework of the spectral-correlation theory of cyclostationary signals is used to present a broad treatment of weak, random signal detection for interception purposes. The relationships among a variety of previously proposed ad hoc detectors, optimum detectors, and newly proposed detectors are established. The spectral-correlation-plane approach to the interception problem is put forth as especially promising for detection, classification, and estimation in particularly difficult environments involving unknown and changing noise levels and interference activity. A fundamental drawback of the popular radiometric methods in such environments is explained.

关键词： Cyclostationary signal Environments Frameworks Unknown interceptions RANDOM signalS feature detections correlation theory

来源：评论

学校读者我要写书评

暂无评论

NONSTATIONARY LEARNING CHARACTERISTICS OF THE LMS ALGORITHM

引用

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS 1987年第10期34卷 1199-1207页

作者： GARDNER, WA Signal and Image Processing Laboratory Department of Electrical and Computer Engineering University of California Davis USA

Upper and lower bounding first-order linear recursions for the mean-squared error realized with the LMS algorithm subjected to a sequence of independent nonstationary training vectors are derived. These bounds coincide to give the exact evolution of mean-squared error for the problem of identification of a nonrecursive time-varying system with white-noise excitation. This leads to an exact formula for time-averaged mean-squared error that is used to study optimization of the step-size parameter for minimum time-average misadjustment. New results on dependence of the minimal step size and the minimum misadjustment on the degree of nonstationarity are obtained.

关键词： Least squares approximation System identification Adaptive filters Algorithm design and analysis Vectors Time varying systems Gaussian distribution signal processing image processing

来源：评论

学校读者我要写书评

暂无评论

CONTROL OF NONLINEAR-SYSTEMS WITH MARKOVIAN PARAMETER CHANGES

引用

IEEE TRANSACTIONS ON AUTOMATIC CONTROL 1991年第2期36卷 233-238页

作者： MARITON, M Signal and Image Processing Laboratory Matra Sep Imagerie et Informatique Saint Quentin-en-Yvelines France

The control of hybrid systems is considered where a totally observed state process is generated by a nonlinear stochastic differential equation whose parameters are functions of a random jump process, called the plant regime. Regime transitions typically represent target maneuvers in a tracking system. The control task is split between a jump detection and identification (JDI) filter and a discrete adaptation, or reconfiguration. A design is presented that takes into account the errors of the JDI device and the plant nonlinearities to produce a near optimal passively adaptive control law with an easily implemented affine structure.

关键词： Nonlinear control systems Control systems Nonlinear systems Hybrid power systems Stochastic systems Differential equations Target tracking Filters Error correction Adaptive control

来源：评论

学校读者我要写书评

暂无评论

ON THE SPECTRUM OF PSEUDO NOISE

引用

PROCEEDINGS OF THE IEEE 1986年第4期74卷 608-609页

作者： GARDNER, WA CHEN, CK Signal and Image Processing Laboratory Department of Electrical and Computer Engineering University of California Davis CA USA

Although the magnitude of the discrete Fourier transform of a maximal-length shift-register sequence is flat, except for its value at zero frequency, the higher resolution spectral content given by the Fourier-series transform is highly erratic. This little-known fact is described, and its ramifications on fast Fourier transforms of one-digit-extended pseudo noise and zero-padded pseudo noise are explained.

关键词： Discrete Fourier transforms Autocorrelation Frequency Interpolation Fourier transforms White noise Fast Fourier transforms Prediction algorithms Fourier series signal processing

来源：评论

学校读者我要写书评

暂无评论

ADVANCES IN MATHEMATICAL-MODELS FOR image-processing

引用

PROCEEDINGS OF THE IEEE 1981年第5期69卷 502-528页

作者： JAIN, AK Signal and Image Processing Laboratory Department of Electrical and Computer Engineering University of California Davis CA USA

Several state-of-the-art mathematical models useful in image processing are considered. These models include the traditional fast unitary transforms, autoregessive and state variable models as well as two-dimensional linear prediction models. These models introduced earlier [51], [52] as low-order finite difference approximations of partial differential equations are generalized and extended to higher order in the framework of linear prediction theory. Applications in several image processing problems, including image restoration, smoothing, enhancement, data compression, spectral estimation, and filter design, are discussed and examples given.

关键词： Mathematical model image processing Predictive models Transforms Finite difference methods Partial differential equations Prediction theory image restoration Smoothing methods Data compression

来源：评论

学校读者我要写书评

暂无评论

A two-stage approach for managing actuators redundancy and its application to fault tolerant flight control

引用

Chinese Journal of Aeronautics 2015年第2期28卷 469-477页

作者： Zhong Lunlong Félix Mora-Camino Tianjin Key Laboratory for Advanced Signal and Image Processing Civil Aviation University of China Automation Research Group of MAIAA ENAC Toulouse University

In safety-critical systems such as transportation aircraft, redundancy of actuators is introduced to improve fault tolerance. How to make the best use of remaining actuators to allow the system to continue achieving a desired operation in the presence of some actuators failures is the main subject of this paper. Considering that many dynamical systems, including flight dynamics of a transportation aircraft, can be expressed as an input affine nonlinear system, a new state repre- sentation is adopted here where the output dynamics are related with virtual inputs associated with the intended operation. This representation, as well as the distribution matrix associated with the effectiveness of the remaining operational actuators, allows us to define different levels of fault tol- erant governability with respect to actuators＇ failures. Then, a two-stage control approach is devel- oped, leading frst to the inversion of the output dynamics to get nominal values for the virtual inputs and then to the solution of a linear quadratic （LQ） problem to compute the solicitation of each operational actuator. The proposed approach is applied to the control of a transportation air- craft which performs a stabilized roll maneuver while a partial failure appears. Two fault scenarios are considered and the resulting performance of the proposed approach is displayed and discussed.

关键词： Actuator allocation Fault tolerant control Flight control Linear quadratic （LQ）problem Nonlinear control

来源：评论

学校读者我要写书评

暂无评论

THE ROLE OF SPECTRAL CORRELATION IN DESIGN AND PERFORMANCE ANALYSIS OF SYNCHRONIZERS

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 1986年第11期34卷 1089-1095页

作者： GARDNER, WA Signal and Image Processing Laboratory Department of Electrical and Computer Engineering University of California Davis CA USA

The popular class of synchronizers that consist of a quadratic nonlinearity followed by a phase-lock loop is investigated, and it is shown that the optimum design of the quadratic transformation is characterized in terms of a spectral correlation function for the signal to be synchronized to. It is also shown that the SNR performance of this quadratic transformation, and the mean-square phase jitter of the phaselock loop are both characterized in terms of spectral correlation functions. The conditions under which the optimum quadratic transformations, for symbol synchronization of BPSK, QPSK, SQPSK, and MSK, and for carrier synchronization of BPSK, reduce to the well-known matched-filter-squarer are identified. In addition, the well-known zeromean-square-phase-jitter condition is generalized from PAM to all synchronizable signals, and is characterized in terms of the spectral correlation function. The low-SNR maximum-likelihood synchronizer for all quadratically synchronizable signals is characterized in terms of a multiplicity of maximum-SNR quadratic spectral-line generators. A closed form implementation in terms of a matched filter, squarer, and symbol-rate-synchronized averager is obtained for BPSK and QPSK signals.

关键词： Performance analysis Frequency synchronization Binary phase shift keying Quadrature phase shift keying Timing Jitter signal generators Matched filters Oscillators Clocks

来源：评论

学校读者我要写书评

暂无评论

A UNIFYING VIEW OF 2ND-ORDER MEASURES OF QUALITY FOR signal CLASSIFICATION

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 1980年第6期28卷 807-816页

作者： GARDNER, WA Signal and Image Processing Laboratory Department of Electrical and Computer Engineering University of California Davis CA USA

The major purpose of this paper is to promote interchange between the fields of pattern recognition and communications, in the realm of statistical classification. The general class of second-order measures of quality for statistical classification is defined. The variety of members in this class that have been used by practitioners or proposed by theorists for numerical pattern-classification and signal waveform-classification are compared and contrasted. The several measures that are the most generally applicable are shown to be either equivalent to each other or characterizable in terms of each other, thereby revealing an inherent unity. For example, the ratio of between-class-scatter to within-class-scatter used in pattern recognition and the ratio of signal-energy to noise-energy used in communications are unified through an identification of signal with between-class-scatter and noise with within-class-scatter. Results on equivalences are stated and proved for waveform classification rather than numerical classification in order to complement the extensive literature on the latter, and to emphasize applicability to communications. This entails introduction of a scatter ratio for waveforms. In a companion paper, second-order measures of quality are used as a basis for a general nearestprototype signal-classification methodology; canonical signal features for this methodology are identified, and a general approach for determining appropriate class prototypes is given. These two papers provide an integrated approach to the design of a complete signal classifier, i.e., feature extraction and discriminant-functional design tailored to fit a minimumdistance discrimination rule.

关键词： Pattern classification signal design signal processing Pattern recognition signal to noise ratio Scattering Prototypes Feature extraction Probability Communications Society

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：