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IEEE Conference on Decision and control

作者： Borhan M. Sanandaji Tyrone L. Vincent Michael B. Wakin Roland Toth Kameshwar Poolla Department of Electrical Engineering and Computer Science Colorado School of Mines Golden CO 80401 USA Delft Center for Systems and Control Delft University of Technology Mekelweg 2 2628 CD Delft The Netherlands Departments of Electrical Engineering and Computer Sciences and Mechanical Engineering University of California Berkeley CA 94720 USA

ISBN: (纸本)9781612848006

In this paper, we consider identifying Auto Regressive with eXternal input (ARX) models for both Linear Time-Invariant (LTI) and Linear Time-Variant (LTV) systems. We aim at doing the identification from the smallest possible number of observations. This is inspired by the field of Compressive Sensing (CS), and for this reason, we call this problem Compressive System Identification (CSI). In the case of LTI ARX systems, a system with a large number of inputs and unknown input delays on each channel can require a model structure with a large number of parameters, unless input delay estimation is performed. Since the complexity of input delay estimation increases exponentially in the number of inputs, this can be difficult for high dimensional systems. We show that in cases where the LTI system has possibly many inputs with different unknown delays, simultaneous ARX identification and input delay estimation is possible from few observations, even though this leaves an apparently ill-conditioned identification problem. We discuss identification guarantees and support our proposed method with simulations. We also consider identifying LTV ARX models. In particular, we consider systems with parameters that change only at a few time instants in a piecewise-constant manner where neither the change moments nor the number of changes is known a priori. The main technical novelty of our approach is in casting the identification problem as recovery of a block-sparse signal from an underdetermined set of linear equations. We suggest a random sampling approach for LTV identification, address the issue of identifiability and again support our approach with illustrative simulations.

关键词： LTI System identification delay estimation Mathematic Identifiability Model structures

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Universal squash model for optical communications using linear optics and threshold detectors

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Physical Review A 2011年第2期84卷 020303(R)-020303(R)页

作者： Chi-Hang Fred Fung H. F. Chau Hoi-Kwong Lo Department of Physics and Center of Computational and Theoretical Physics University of Hong Kong Pokfulam Road Hong Kong Center for Quantum Information and Quantum Control Department of Physics and Department of Electrical & Computer Engineering University of Toronto Toronto Ontario M5S 3G4 Canada

Transmission of photons through open-air or optical fibers is an important primitive in quantum-information processing. Theoretical descriptions of this process often consider single photons as information carriers and thus fail to accurately describe experimental implementations where any number of photons may enter a detector. It has been a great challenge to bridge this big gap between theory and experiments. One powerful method for achieving this goal is by conceptually squashing the received multiphoton states to single-photon states. However, until now, only a few protocols admit a squash model; furthermore, a recently proven no-go theorem appears to rule out the existence of a universal squash model. Here we show that a necessary condition presumed by all existing squash models is in fact too stringent. By relaxing this condition, we find that, rather surprisingly, a universal squash model actually exists for many protocols, including quantum key distribution, quantum state tomography, Bell's inequality testing, and entanglement verification.

关键词： Photons

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Evaluation of functional connectivity in control and ADHD subjects by generalized Canonical Correlation and Probabilistic Independent Component Analysis

Evaluation of functional connectivity in control and ADHD su...

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Iranian Conference of Biomedical engineering (ICBME)

作者： AmirEhsan Lashkari Hamid Soltanian-Zadeh GholamAli Hosseinzadeh Control and Intelligent Processing Center of Excellence Electrical and Computer Engineering Department Faculty of Engineering University of Tehran Tehran Iran Radiology Image Analysis Laboratory Henry Ford Health System Detroit MI USA

Functional connectivity can be evaluated by temporal correlation between spatial neurophysiologic events or correlation between neural activities of brain regions. Unlike anatomical connectivity which represents physical connections between two brain regions, functional connectivity investigates interactions between brain regions. In this study, we implemented and evaluated Probabilistic Independent Component Analysis (PICA) and generalized Canonical Correlation Analysis (gCCA) on resting state data of healthy subjects and subjects with ADHD disorders from NITRC database. This was done to detect brain functional connectivity and compare the results in normal and diseased subjects. In addition, speed of the methods was compared. Our study shows that relative to PICA, gCCA has higher precision and accuracy and lower computational complexity and run time in addition to capability of extracting more reproducible statistical maps in both control and ADHD subjects.

关键词： Correlation Magnetic resonance imaging Independent component analysis Educational institutions Biomedical engineering Probabilistic logic Basal ganglia

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Annual International Conference of the IEEE engineering in Medicine and Biology Society

作者： Jinyin Zhang Gustavo Sudre Xin Li Wei Wang Douglas J. Weber Anto Bagic Department of Electrical and Computer Engineering Carnegie Mellon University Program in Neural Computation (PNC) Center for the Neural Basis of Cognition Carnegie Mellon University Department of Physical Medicine & Rehabilitation and the Department of Bioengineering University of Pittsburgh Department of Neurology University of Pittsburgh

ISBN: (纸本)9781424441211

To investigate the neural activity corresponding to different cognitive states, it is of great importance to localize the cortical areas that are associated with task-related modulation. In this paper, we propose a novel discriminant pattern source localization (DPSL) method to analyze MEG data. Unlike most traditional source localization methods that aim to find "dominant" sources, DPSL is developed to capture the "differential" sources that distinguish different cognitive states. As will be demonstrated by the experimental results in this paper, the proposed DPSL method offers superior accuracy to identify the spatial locations of task-related sources.

关键词： Position measurement discriminant analysis Magnetoencephalography Localization method

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Trajectory extension methods for model predictive direct torque control

Trajectory extension methods for model predictive direct tor...

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Annual IEEE Conference on Applied Power Electronics Conference and Exposition (APEC)

作者： Yashar Zeinaly Tobias Geyer Bo Egardt Delft Center for Systems and Control Delft University of Technnology Netherlands Department of Electrical and Computer Engineering University of Auckland New Zealand Department of Signals and Systems Chalmers University of Technology Sweden

This paper focuses on model predictive direct torque control (MPDTC), which is a recent control scheme for three-phase ac electric drives combining the notions of model predictive control (MPC) and direct torque control (DTC). Using a dynamic model of the drive, MPDTC predicts several future switch transitions, extends the outputs and chooses the inverter switch positions that minimize the switching frequency or the switching losses. The performance of MPDTC depends on the accuracy of the predictions. However, MPTDC schemes with very accurate predictions are computationally demanding necessitating very fast controller hardware. New methods for extending the output trajectories are proposed that yield fast yet accurate predictions giving rise to a computationally efficient MPDTC scheme. The advantages of the proposed methods are shown in terms of the associated computational complexity and the accuracy of the predictions.

关键词： Trajectory Stators Switches Rotors Inverters computational modeling Predictive models

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Fire evacuation model with confidence intervals

Fire evacuation model with confidence intervals

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2011 7th IEEE International Conference on Automation Science and engineering, CASE 2011

作者： Gao, Yuan Luh, Peter B. Zhao, Qianchuan Zhang, Hui Wu, Nan Qiao, Lifeng Tsinghua University Beijing 100084 China Tsinghua-UTC Research Institute for Integrated Building Energy Safety and Control System China Department of Electrical and Computer Engineering University of Connecticut United States Chair Professors Group CFINS Tsinghua University Beijing China Center for Public Safety Research Tsinghua University Beijing 100084 China UTRC China

ISBN: (纸本)9781457717307

In building fire evacuation, good guidance can speed up egress process and occupants may be injured due to lack of information and guidance. There are many studies on building egress systems, which use relevant information (e.g., fire condition and its evolution) to calculate and provide guidance to occupants. However, information used to generate guidance may be uncertain, and it is difficult to provide the guidance under uncertainty. How to provide effective guidance to occupants under uncertainty and how to evaluate the confidence of the guidance are critical issues. To describe the confidence of the guidance, the concept of "confidence intervals" is used. By comparing "confidence intervals" with a threshold, acceptable guidance is provided. Testing examples show that the confidence of the guidance can be evaluated and unacceptable guidance can be differentiated with the use of confidence intervals. © 2011 IEEE.

关键词： Fires

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Tuning method for second-order active disturbance rejection control

Tuning method for second-order active disturbance rejection ...

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Chinese control Conference (CCC)

作者： Xing Chen Donghai Li Zhiqiang Gao Chuanfeng Wang State Key Lab of Power Systems Dept of Thermal Engineering Tsinghua University Beijing 100084 China The Center for Advanced Control Technologies Department of Electrical and Computer Engineering Cleveland State University OH 44115 USA

A simple tuning method for second-order active disturbance rejection control (ADRC) that achieves high performance and good robustness for a wide range of processes is presented. ADRC is a novel control strategy whose exciting performance has been shown by literatures. The proposed method makes ADRC become easy to tune and more practical. Once the desired settling time is given, only one parameter need to be tuned during the design procedure, which can be found by monotonously increasing. Examples are given to show the effectiveness and flexibility of the method. Simulations demonstrate that second-order ADRC can handles processes with various characteristics, including low- and high-order, large dead time, non-minimum phase, unstable and distributed parameter systems.

关键词： Tuning Robustness Observers Mathematical model Transfer functions Process control Stability analysis

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Universal Steganalysis Based on Local Prediction Error in Wavelet Domain

Universal Steganalysis Based on Local Prediction Error in Wa...

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International Conference on Intelligent Information Hiding and Multimedia Signal Processing (IIHMSP)

作者： Anahita Shojaei-Hashemi Mostafa Mehdipour-Ghazi Shahrokh Ghaemmaghami Hamid Soltanian-Zadeh School of Electrical and Computer Engineering College of Engineering University of Tehran Tehran Iran Electronics Research Institute Sharif University of Technology Tehran Iran Image Analysis Laboratory Department of Radiology Henry Ford Health System Detroit MI USA Control and Intelligent Processing Center of Excellence School of Electrical and Computer Engineering College of Engineering University of Tehran Tehran Iran

A passive universal image steganalysis method is proposed that is shown to be of higher detection accuracy than existing truly blind steganalysis methods including Farid's and the WAM. This is achieved by improving some weaknesses of Farid's steganalysis scheme in feature extraction, that is, instead of deriving an over-determined equation system for each sub band of the wavelet decomposition, the sub bands are divided into overlapping blocks and an over-determined equation system is constructed for each block. To guarantee the existence of finite answers, the over-determined equation systems are solved in a way different from Farid's by using Moore-Penrose pseudo-inverse concept. Further improvement to the performance is achieved by adding diagonal directions and increasing the number of moments. The comparative evaluations confirm the superiority of the proposed method over prevalent blind steganalysis schemes.

关键词： Equations Mathematical model Payloads Transform coding Correlation Educational institutions Reliability

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A Review of Energy Efficiency in Data Processing centers

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Journal of Energy and Power engineering 2011年第4期5卷 361-372页

作者： C. Redondo A. Fern/mdez Castile and Leon Technological Center for Supercomputing （FCSC） Edificio CRAI- TIC Campus de Vegazana s/n University of Le6n E-24071-Lean Spain Electrical Engineering and Systems Engineering and Automatic Control Department Faculty of lndustrial and Computer Engineering University of Leon E-24071-Leon Spain

This article explores, through a case study, measures of energy efficiency in data processing centers. An analysis of this case demonstrates how the design criteria could improve the rate of consumption in IT centers, which is currently the second most contaminating industry on the planet, and is the responsible for 2% of CO2 emissions, surpassed only by the aeronautical industry. The present and future situation of IT center energy consumption and associated environmental effects is analyzed, and also looks at how state-of-the-art technology, correctly implemented, could ensure significant rationalization of data processing center energy consumption. The article will examine optimization techniques, specific problems and case studies.

关键词： Energy management data processing centers energy efficiency.

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Wavelet-based EEG denoising for automatic sleep stage classification

Wavelet-based EEG denoising for automatic sleep stage classi...

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International Conference on Electronics, Communications and computers (CONIELECOMP)

作者： Edson Estrada Homer Nazeran Gustavo Sierra Farideh Ebrahimi S. Kamaledin Setarehdan Department of Electrical and Computer Engineering University of Texas El Paso El Paso TX USA Autónoma de Ciudad Juárez Instituto de Ciencias Biomédicas Universidad Chih Mexico Control and Intelligent Processing Center of excellence Department of Electrical and Computer Engineering University of Tehran Tehran Iran

In automatic sleep stage classification, as in any other signal processing task involving the easily contaminated EEG signals, denoising constitutes a crucial pre-processing step that must be addressed before carrying out further analysis on the EEG signals. Discrete wavelet transform offers an effective solution for denoising nonstationary signals such as EEG due to its shrinkage property. In this paper, we explored the application of wavelet denoising method to EEG signals acquired during different sleep stages classified according to the RK rules, with the objective to identify suitable thresholding rules and threshold values. Preliminary results showed that the combination of soft thresholding rule applied to the Detailed wavelet coefficients with the Universal threshold value produced better performance measures such as a smaller Minimum Squared Error (MSE) and a larger signal-to-Noise Ratio (SNR). Similarly improved results were obtained for Stage 1, Stage 2, Stage 3, Stage 4 and REM stage EEG signals using this combination. Such thresholding rule and values are equally well applicable to denoising EEG epochs acquired from deep sleep stages.

关键词： Electroencephalography Discrete wavelet transforms Noise reduction Signal to noise ratio Sleep Finite impulse response filter

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