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IEEE Energytech

作者： Peter Kascak Ralph Jansen Timothy Dever Aleksandr Nagorny Kenneth Loparo NASA Glenn Research Center Cleveland OH USA ResMed Motor Technologies Inc. Chatsworth CA USA Department of Electrical Engineering and Computer Science Case Western Reserve University Cleveland OH USA

In standard motor applications, traditional mechanical bearings represent the most economical approach to rotor suspension. However, in certain high performance applications, rotor suspension without bearing contact is either required or highly beneficial. Such applications include very high speed, extreme environment, or limited maintenance access applications. This paper extends upon a novel bearingless motor concept, in which full five-axis levitation and rotation of the rotor is achieved using two motors with opposing conical air-gaps. By leaving the motors' pole-pairs unconnected, different d-axis flux in each pole-pair is created, generating a flux imbalance which creates lateral force. Note this is approach is different than that used in previous bearingless motors, which use separate windings for levitation and rotation. This paper will examine the use of feedforward control to counteract synchronous whirl caused by rotor imbalance. Experimental results will be presented showing the performance of a prototype bearingless system, which was sized for a high speed flywheel energy storage application, with and without feedforward control.

关键词： Rotors Permanent magnet motors Synchronization Force Induction motors Reluctance motors

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Comparison of Fixed Speed Wind Turbines Models: A Case Study

Comparison of Fixed Speed Wind Turbines Models: A Case Study

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Annual Conference on IEEE Industrial Electronics Society

作者： Gonzalo Bustos Luis S. Vargas Freddy Milla Doris Saez Hamid Zareipour Alfredo Nunez Electrical Engineering Department Universidad de Chile Electrical and Computer Engineering Department University of Calgary Delft Center for Systems and Control Delft University of Technology

ISBN: (纸本)9781467324199

This paper presents a model comparison of a fixed speed wind turbine (FSWT) operating on a real wind farm. By relying on real data obtained from a wind farm operating in the Chilean Interconnected System, three different models are identified and analyzed. First, a phenomenological model based on physical principles governing the production of electricity from wind power is considered. This model is fine-tuned in accordance with practical considerations, such as wind correction factors. Then, a linear model and a Takagi & Sugeno (T&S) fuzzy model are identified. From the experimental results, the linear model is the simplest one, but also the one that presents the worst performance indexes. The best prediction capability is obtained with the T&S model;however, in terms of interpretability, the phenomenological model outperforms the other two black-box models.

关键词： Wind Turbine Model Validation Dynamic Simulation Fixed Speed Wind Turbine Fuzzy Modeling

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Fractional-order circuit elements with memory

Fractional-order circuit elements with memory

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International Carpathian control Conference (ICCC)

作者： 1Ivo Petráš YangQuan Chen Institute of Control and Informatization of Production Processes BERG Faculty Technical University of Košice Kosice Slovakia Department of Electrical and Computer Engineering Center for Self-Organizing and Intelligent Systems Utah State University Logan UT USA

This paper deals with the fractional-order memristive, memcapacitative, and meminductive systems and their utilization in design of the new circuits with memory. We provide a mathematical description of such systems by using a technique of the fractional calculus. Some possible applications of “mem” systems are mentioned in article as well.

关键词： Memristors Capacitors Inductors Fractional calculus Equations

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Quantum key distribution with delayed privacy amplification and its application to the security proof of a two-way deterministic protocol

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Physical Review A 2012年第3期85卷 032308-032308页

作者： Chi-Hang Fred Fung Xiongfeng Ma H. F. Chau Qing-yu Cai 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 Canada State Key Laboratory of Magnetics Resonances and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 People's Republic of China

Privacy amplification (PA) is an essential postprocessing step in quantum key distribution (QKD) for removing any information an eavesdropper may have on the final secret key. In this paper, we consider delaying PA of the final key after its use in one-time pad encryption and prove its security. We prove that the security and the key generation rate are not affected by delaying PA. Delaying PA has two applications: it serves as a tool for significantly simplifying the security proof of QKD with a two-way quantum channel, and also it is useful in QKD networks with trusted relays. To illustrate the power of the delayed PA idea, we use it to prove the security of a qubit-based two-way deterministic QKD protocol which uses four states and four encoding operations.

关键词： QUANTUM communication PUBLIC key cryptography QUBITS COMMUNICATION & technology INFORMATION technology -- Security measures DATA encryption (computer science)

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Continuous-variable quantum key distribution using thermal states

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Physical Review A 2012年第2期86卷 022318-022318页

作者： Christian Weedbrook Stefano Pirandola Timothy C. Ralph Center for Quantum Information and Quantum Control Department of Electrical and Computer Engineering and Department of Physics University of Toronto Toronto M5S 3G4 Canada Department of Computer Science University of York Deramore Lane York YO10 5GH United Kingdom Centre for Quantum Computation and Communication School of Mathematics and Physics University of Queensland St Lucia Queensland 4072 Australia

We consider the security of continuous-variable quantum key distribution using thermal (or noisy) Gaussian resource states. Specifically, we analyze this against collective Gaussian attacks using direct and reverse reconciliation where both protocols use either homodyne or heterodyne detection. We show that in the case of direct reconciliation with heterodyne detection, an improved robustness to channel noise is achieved when large amounts of preparation noise is added, as compared to the case when no preparation noise is added. We also consider the theoretical limit of infinite preparation noise and show a secure key can still be achieved in this limit provided the channel noise is less than the preparation noise. Finally, we consider the security of quantum key distribution at various electromagnetic wavelengths and derive an upper bound related to an entanglement-breaking eavesdropping attack and discuss the feasibility of microwave quantum key distribution.

关键词： CONTINUOUS functions VARIABLES (Mathematics) QUANTUM theory ENERGY levels (Quantum mechanics) GAUSSIAN distribution ROBUST control

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A Recursive Local Linear Estimator for Identification of Nonlinear ARX Systems *

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IFAC Proceedings Volumes 2012年第16期45卷 1517-1522页

作者： Wen-Xiao Zhao Wei Xing Zheng Er-Wei Bai Key Laboratory of Systems and Control Academy of Mathematics and Systems Science CAS Beijing P. R. China National Center for Mathematics and Interdisciplinary Sciences CAS Beijing P. R. China School of Computing Engineering and Mathematics University of Western Sydney Penrith NSW 2751 Australia Department of Electrical and Computer Engineering University of Iowa Iowa City IA 52242 USA

In this work, we propose a recursive local linear estimator (RLLE) for identification of nonlinear autoregressive systems with exogenous inputs, along with an analysis of its strong consistency and asymptotical mean s... 详细信息

关键词： Nonlinear ARX systems recursive identification local linear estimator almost sure convergence

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Finite-key analysis for measurement-device-independent quantum key distribution

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Physical Review A 2012年第2期86卷 022332-022332页

作者： Ting-Ting Song Qiao-Yan Wen Fen-Zhuo Guo Xiao-Qing Tan State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China Center for Quantum Information and Quantum Control Department of Electrical and Computer Engineering and Department of Physics University of Toronto Toronto Ontario Canada M5S 3G4 Department of Mathematics College of Information Science and Technology Jinan University Guangzhou Guangdong 510632 China

The length of signal pulses is finite in practical quantum key distribution. The finite-key analysis of an unconditional quantum key distribution is a burning problem, and the efficient quantum key distribution protocol suitable for practical implementation, measurement-device-independent quantum key distribution (MDI QKD), was proposed very recently. We give the finite-key analysis of MDI QKD, which removes all detector side channels and generates many orders of key rate higher than that of full-device-independent quantum key distribution. The secure bound of the ultimate key rate is obtained under the statistical fluctuations of relative frequency, which can be applied directly to practical threshold detectors with low detection efficiency and highly lossy channels. The bound is evaluated for reasonable values of the observed parameters. The simulation shows that the secure distance is around 10 km when the number of sifted data is 1010. Moreover the secure distance would be much longer in practice because of some simplified treatments used in our paper.

关键词： QUANTUM measurement DEPENDENCE (Statistics) QUANTUM statistics DETECTORS FLUCTUATIONS (Physics) SIMULATION methods & models ENERGY consumption

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Voxel-based treatment prediction of glioblastoma multiform tumor using diffusion tensor imaging

Voxel-based treatment prediction of glioblastoma multiform t...

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IEEE EMBS International Conference on Information Technology Applications in Biomedicine (ITAB)

作者： Hadi Sabahi Hamid Soltanian-Zadeh Lisa Scarpace Tom Mikkelsen Control and Intelligent Processing Center of Excellence School of Electrical and Computer Engineering University of Tehran Tehran Iran Image Analysis Laboratory Radiology Department Henry Ford Hospital Detroit MI USA Hermelin Brain Tumor Research Center Neurosurgery Department Henry Ford Health System Detroit MI USA

This paper proposes a method to predict the effect of Bevacizumab therapy on Glioblastoma Multiform (GBM) tumors. The prediction is critical for effective treatment planning. The proposed method is developed and evaluated using Diffusion Tensor Imaging (DTI) and post-contrast T1-weighted Magnetic Resonance Images (pc-T1-MRI) of 14 patients with GBM tumors gathered before and after the treatment. First, the proposed method calculates diffusion anisotropy indices (DAI) of all voxels in the brain. These diffusion anisotropy indices are Fractional Anisotropy (FA), Mean Diffusivity (MD), Relative Anisotropy (RA), and Volume Ratio (VR). Then, it registers post-treatment pc-T1-MRI and pre-treatment DAI maps to pre-treatment pc-T1-MRI. Next, it uses a thresholding method to segment the tumor from pc-T1-MRI studies. Comparing Gd-enhanced voxels of the pre- and post-treatment pc-T1-MRI, the DAIs of the tumor are labeled based on their response to the treatment. The voxels of 7 patients are randomly selected to train 4 classifiers (ANN, SVM, KNN, and ANFIS) and then all voxels of the other 7 patients are used to test them. For each classifier, four performance measures (sensitivity, specificity, positive predictive value, and accuracy) are calculated. Experimental results show that the ANFIS is more accurate than the other classifiers in predicting the treatment response.

关键词： Support vector machines Noise Magnetic resonance imaging Sensitivity Tumors Biomedical imaging Artificial neural networks

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Evading Quantum Mechanics: engineering a Classical Subsystem within a Quantum Environment

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Physical Review X 2012年第3期2卷 031016-031016页

作者： Mankei Tsang Carlton M. Caves Department of Electrical and Computer Engineering National University of Singapore 4 Engineering Drive 3 Singapore 117583 Department of Physics National University of Singapore 2 Science Drive 3 Singapore 117551 Center for Quantum Information and Control University of New Mexico MSC07-4220 Albuquerque New Mexico 87131-0001 USA Centre for Engineered Quantum Systems School of Mathematics and Physics The University of Queensland St. Lucia Brisbane 4072 Australia

Quantum mechanics is potentially advantageous for certain information-processing tasks, but its probabilistic nature and requirement of measurement backaction often limit the precision of conventional classical information-processing devices, such as sensors and atomic clocks. Here we show that, by engineering the dynamics of coupled quantum systems, it is possible to construct a subsystem that evades the measurement backaction of quantum mechanics, at all times of interest, and obeys any classical dynamics, linear or nonlinear, that we choose. We call such a system a quantum-mechanics-free subsystem (QMFS). All of the observables of a QMFS are quantum-nondemolition (QND) observables; moreover, they are dynamical QND observables, thus demolishing the widely held belief that QND observables are constants of motion. QMFSs point to a new strategy for designing classical information-processing devices in regimes where quantum noise is detrimental, unifying previous approaches that employ QND observables, backaction evasion, and quantum noise cancellation. Potential applications include gravitational-wave detection, optomechanical-force sensing, atomic magnetometry, and classical computing. Demonstrations of dynamical QMFSs include the generation of broadband squeezed light for use in interferometric gravitational-wave detection, experiments using entangled atomic-spin ensembles, and implementations of the quantum Toffoli gate.

关键词： Optics Quantum Physics Quantum Information

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Effects of Improved Adaptive Gamma Correction Method on Wireless Capsule Endoscopy Images: Illumination Compensation and Edge Detection

Effects of Improved Adaptive Gamma Correction Method on Wire...

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Iranian Conference on electrical engineering

作者： Mahdi Alizadeh Alireza Talebpour Hamid Soltanian-Zadeh Seyed Mahmoud Reza Aghamiri Department of Radiation Medicine Engineering Shahid Beheshti University Control and Intelligent Processing Center of Excellence (CIPE) School of Electrical and Computer Engineering University of Tehran

ISBN: (纸本)9781467311496

Several methods for adjusting image contrast have been developed in the field of image processing for image enhancement. Illumination is one of the most significant factors affecting the appearance of an image. Improper illumination causes a variety of problems in practice and thus, it is necessary to compensate for nonuniform illumination. Wireless Capsule Endoscopy (WCE) images suffer from this problem too. We propose an improved Adaptive Gamma Correction Method (AGCM) to compensate for nonuniform illumination in WCE color images. The experiments have shown that the proposed AGCM performs well in improving image quality. The WCE images obtained with AGCM are also better than those obtained with histogram equalization and adaptive histogram equalization in terms of brightness constancy, overall visual rendition and contrast. The Peak Signal to Noise Ratio (PSNR) and Contrast to Noise Ratio (CNR) values are also higher for AGCM than for other correction algorithms. Also, the differences between edge pixels and neighboring pixels in the WCE images are increased. We use a color variant of the canny operator for color edge detection. By using this method, 65% of the borders are detected correctly, while the detection rate is 45% without using this method.

关键词： Adaptive gamma correction method Wireless capsule endoscopy Edge detection Illumination Color variant of canny operator

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