检索结果-内蒙古大学图书馆

Using semi-definite programming for multi-constrained H-2 controller design in active noise and vibration control

JOURNAL OF VLSI signal processing SYSTEMS FOR signal IMAGE AND VIDEO TECHNOLOGY 1996年第1期14卷 57-66页

作者： Olkin, JA Titterton, PJ 1. Applied Control and Signal Processing Group SRI International 94025 Menlo Park CA

We consider the practical design of linear controllers to meet a given set of H-2 specifications. The Q-parametrization reduces the problem to a quadratic minimization subject to multiple quadratic constraints, which we solve using semi-definite programming (SDP) methods. Each SDP iteration requires calculating a primal and dual search direction and minimizing the cost function along the plane defined by these search directions. The primal direction requires solving a least squares problem whose normal equation matrix is composed of a block-Toeplitz portion plus other structured matrices. We make use of Kronecker products and FFT's to greatly reduce the calculation. The dual search direction and plane search are accelerated by low-rank representations of the SDP structured matrices. As an example, we design controllers which explore the optimal tradeoff between in-band residual and out-of-band enhancement of acoustic radiation from a (mathematically modeled) submerged spherical shell, while simultaneously constraining two sensitivity measures. For this example we show that significant reduction in out-of-band enhancement is possible with only minor in-band penalties.

关键词： Linear programming

来源：评论

学校读者我要写书评

暂无评论

ADAPTIVE SET-MEMBERSHIP IDENTIFICATION IN O (M) TIME FOR LINEAR-IN-PARAMETERS MODELS

引用

IEEE TRANSACTIONS ON signal processing 1993年第5期41卷 1906-1924页

作者： DELLER, JR ODEH, SF Department of Electrical Engineering Control Systems and Signal Processing Group: Speech Processing Laboratory Michigan State University East Lansing MI USA Department of Electrical Engineering Control Systems and Signal Processing Group: Speech Processing Laboratory Michigan State University East Lansing MI USA Department of Electrical Engineering University of Jordan Amman Jordan

This paper describes some fundamental contributions to the theory and applicability of optimal bounding ellipsoid (OBE) algorithms for signal processing. All reported OBE algorithms are placed in a general framework which fruitfully demonstrates the relationship between the set-membership principles and least square error identification. Within this framework, flexible measures for adding explicit adaptation capability are formulated and demonstrated through simulation. Computational complexity analysis of OBE algorithms reveals that they are of O (m2) complexity per data sample with m the number of parameters identified, in spite of their well-known propensity toward highly selective updating. Two very different approaches are described for rendering a specific OBE algorithm, the set-membership weighted recursive least squares algorithm, of O (m) complexity. The first approach involves an algorithmic solution in which a suboptimal test for innovation is employed. The performance is demonstrated through simulation. The second method is an architectural approach in which complexity is reduced through parallel computation.

关键词： signal processing algorithms Samarium Least squares methods signal processing Speech processing Adaptive signal processing Computational complexity Algorithm design and analysis Testing Technological innovation

来源：评论

学校读者我要写书评

暂无评论

Distributed bearing-only formation control with four agents and a weak control law

Distributed bearing-only formation control with four agents ...

引用

9th IEEE International Conference on control and Automation, ICCA 2011

作者： Bishop, Adrian N. NICTA Control and Signal Processing Group Canberra Research Laboratory Australia

ISBN: (纸本)9781457714757

A distributed control law for quadrilateral (four-agent) formation control with bearing-only measurements and relative pair-wise inter-agent angle constraints is introduced. The control law is weak in the sense that each agent is free to choose their own heading within a relatively large region of values. Indeed, the agents can determine their heading independently at run-time given any criteria they desire as long as certain relaxed conditions are met. A strong convergence result is established with ensures the desired formation configuration is globally asymptotically stable. Illustrative examples are provided to demonstrate the claims. © 2011 IEEE.

关键词： control theory

来源：评论

学校读者我要写书评

暂无评论

Higher-order time-frequency analysis and its application to fault detection in rotating machinery

引用

MECHANICAL SYSTEMS AND signal processing 1997年第4期11卷 637-650页

作者： Lee, SK White, PR Signal Processing and Control Group Institute of Sound and Vibration Research University of Southampton Southampton SO17 1BJ U.K.

Impulsive acoustic and vibration signals within rotating machinery are often induced by irregular impacting. The detection of these impulses can be useful for fault diagnosis purposes. Recently there has been an increasing trend towards the use of higher-order statistics for fault detection within mechanical systems based on the observation that impulsive signals tend to increase the kurtosis values. This paper considers the use of the third- and fourth-order Wigner moment spectra, called the Wigner bi- and tri-spectra respectively, for analysing such signals. Expressions for the auto- and cross-terms in these distributions are presented and discussed. It is shown that the Wigner trispectrum is a more suitable analysis tool and its performance is compared to its second-order counterpart for detecting impulsive signals. These methods are also applied to measured data sets from a car engine and an industrial gearbox. (C) 1997 Academic Press Limited.

关键词： Rotating machinery

来源：评论

学校读者我要写书评

暂无评论

Mapping scalp topographies of rhythmic EEC activity using temporal decorrelation based constrained ICA

Mapping scalp topographies of rhythmic EEC activity using te...

引用

Conference Proceedings - 26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBC 2004

作者： James, C.J. Hesse, C.W. Signal Processing and Control Group ISVR University of Southampton Southampton United Kingdom

Independent Component Analysis (ICA) methods are being increasingly applied to the analysis of electromagnetic (EM) brain signals. However, these powerful techniques still generally require subjective a posteriori analysis in order to visualise neurophysiologically meaningful components in the outputs. Standard implementations of ICA are restrictive mainly due to the square mixing assumption (i.e., as many sources as measurement channels) - this is especially so with large multichannel recordings. There are many instances in neurophysiological analysis where there is strong a priori information about the signals being sought;as in tracking the changing scalp topographies of rhythmic activities. Through constraining the ICA solution it is possible to extract signals that are statistically independent, yet which are similar to some reference signal which incorporates the a priori information. We demonstrate this method on a multichannel recording of an epileptiform electroencephalogram (EEG), where we automate the repeated simultaneous extraction of both rhythmic seizure activity, as well as alpha-band activity, over an epoch of EEG. Subjective analysis of the results shows scalp topographies with realistic spatial distributions which conform to our neurophysiologic expectations. This work shows that constraining ICA can be a very useful technique, especially in automated systems and we demonstrate that this can be successfully applied to EM brain signal analysis.

关键词： Electroencephalography

来源：评论

学校读者我要写书评

暂无评论

On false-data attacks in robust multi-sensor-based estimation

On false-data attacks in robust multi-sensor-based estimatio...

引用

9th IEEE International Conference on control and Automation, ICCA 2011

作者： Bishop, Adrian N. Savkin, Andrey V. Control and Signal Processing Group Canberra Research Lab Australia Sydney Australia

ISBN: (纸本)9781457714757

State estimation in critical networked infrastructure such as the transportation and electricity (smart grid) networks is becoming increasingly important. Consequently, the security of state estimation algorithms has been identified as an important design factor in order to safeguard critical infrastructure. In this paper we study false-data attacks on robust state estimation in multi-sensor-based systems. Specifically, we suppose there is a group of attacking entities that want to compromise the integrity of the state estimator by hijacking certain sensors and distorting their outputs. We consider an underlying class of uncertain (discrete-time) systems and we outline a decentralized set-valued state estimation algorithm that recursively produces an ellipsoidal set of all those state estimates consistent with the measurements and modelling assumptions. We then show that in order for the attack to go undetected, the distorted measurements need to be carefully designed. In particular, we compute a set of those measurements which are consistent with the modelling assumptions. This set then forms the basis for a test to detect false-data attacks and provides a quantitative measure of the resilience of the system to false-data attacks. We also briefly discuss how an attacker can design their false-data attack in some optimal fashion while ensuring it goes undetected. © 2011 IEEE.

关键词： Critical infrastructures

来源：评论

学校读者我要写书评

暂无评论

On the use of spectrally constrained ICA applied to single-channel letal EEG recordings within a dynamical embedding framework

On the use of spectrally constrained ICA applied to single-c...

引用

2005 27th Annual International Conference of the Engineering in Medicine and Biology Society, IEEE-EMBS 2005

作者： James, C.J. Hesse, C.W. Signal Processing and Control Group ISVR University of Southampton Southampton United Kingdom

ISBN: (纸本)0780387406

Within a dynamical embedding (DE) framework it is possible to extract information on multiple-sources underlying just a single channel recording of electromagnetic brain activity. Independent Component Analysis (ICA) is a technique which, when used in conjunction with DE, can identify and extract statistically independent sources underlying these single channel recordings. However, these powerful techniques still generally require subjective a posteriori analysis in order to visualise neurophysiologically meaningful components in the outputs. For this reason we introduce a variant of ICA known as constrained ICA (cICA) which allows for the extraction of one of many sources underlying the measurement signal, through the provision of a basic reference signal. This constraint can be chosen to reflect neurophysiological prior knowledge of the sources in question given the measured signal. Here we present a technique which allows for the application of spectral constraints on single channel recordings of epileptic EEG data. We show that through a combination of DE and cICA it is possible to extract meaningful information on epileptic seizures and other rhythmic activity from just a single channel of EEG. We further show that accurate extraction of the sources of interest is not critically dependent on the closeness of the measurement channel to the location of the source activity. © 2005 IEEE.

关键词： Electroencephalography

来源：评论

学校读者我要写书评

暂无评论

Classification of Fruits using Probabilistic Neural Networks - Improvement using Color Features

Classification of Fruits using Probabilistic Neural Networks...

引用

IEEE Region 10 Conference on TENCON

作者： Mustafa, Nur Badariah Ahmad Arumugam, Kumutha Ahmed, Syed Khaleel Sharrif, Zainul Abidin Md Signal Processing and Control Systems (SPaCS) Research Group College of Engineering Universiti Tenaga Nasional Malaysia

ISBN: (纸本)9781457702556

This paper presents a novel approach for the development of an intelligent fruit sorting system using techniques from Digital Image processing and Artificial Neural Networks. The aim is to develop a fast and effective classification method along with a target of 100% efficiency. Five fruits;i.e., apples, bananas, carrots, mangoes and oranges were analysed and seventeen features were extracted based on the fruits' morphological and colour characteristics. A regular digital camera was used to acquire the images, and all manipulations were performed in a MATLAB/SIMULINK environment. The results obtained were a significant improvement over a previous study.

关键词： Fruit Classification Colour Recognition Morphological Feature Analysis PNN RGB HSI

来源：评论

学校读者我要写书评

暂无评论

Blind source separation in single-channel EEG analysis: An application to BCI

Blind source separation in single-channel EEG analysis: An a...

引用

28th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS'06

作者： James, C.J. Wang, S. IEEE Signal Processing and Control Group ISVR University of Southampton Southampton United Kingdom

ISBN: (纸本)1424400325

In this work we present a technique for applying Blind Source Separation (BSS) to single channel recordings of Electromagnetic (EM) brain signals. Single channel recordings of brain signals are preprocessed through the method of delays, and the delay matrix processed with the BSS technique described here called LSDIAGTD which uses temporal decorrelation to implement the now popular Independent Component Analysis (ICA) algorithm. This allows the identification and extraction of statistically independent sources underlying these single channel recordings. In particular we depict the analysis of single channel recordings from a Brain-Computer Interfacing paradigm. We show that BSS technique applied in this way extracts a series of codebook vectors representing the spectral content underlying the recorded signal. It then becomes possible to identify and extract particular rhythmic activity underlying the recordings. We show that rhythmic activity in the 8 to 12Hz band can be extracted in the case of imagined hand movements for a particular BCI paradigm. © 2006 IEEE.

关键词： Electroencephalography

来源：评论

学校读者我要写书评

暂无评论

Automatic choice of the number of nearest neighbors in locally linear embedding 1

引用

Lecture Notes in Computer Science

作者： Valencia-Aguirre, Juliana Álvarez-Mesa, Andrés Daza-Santacoloma, Genaro Castellanos-Domínguez, Germán Control and Digital Signal Processing Group Universidad Nacional de Colombia Manizales Colombia

ISBN: (数字)9783642102684

ISBN: (纸本)3642102670

Locally linear embedding (LLE) is a method for nonlinear dimensionality reduction, which calculates a low dimensional embedding with the property that nearby points in the high dimensional space remain nearby and similarly co-located with respect to one another in the low dimensional space [1]. LLE algorithm needs to set up a free parameter, the number of nearest neighbors k. This parameter has a strong influence in the transformation. In this paper is proposed a cost function that quantifies the quality of the embedding results and computes an appropriate k. Quality measure is tested on artificial and real-world data sets, which allow us to visually confirm whether the embedding was correctly calculated. © 2009 Springer-Verlag Berlin Heidelberg.

关键词： Cost functions

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：