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7th IET International Conference on Power Electronics, Machines and Drives (PEMD 2014)

作者： K Bouhoune K Yazid M S Boucherit Power and Industrial Systems Laboratory Faculty of Electronics and Computer Science University of Science Algeria Process Control Laboratory Department of Electrical Engineering Polytechnic National School PO Box 182 10 Hassan Badi El-Harrach 16200 Algiers Algeria

In addition to simplicity, the DTC of the IM allows a good torque control in steady-state and transient operating conditions. However, high torque ripple is produced, which is reflected in speed estimation responses. It also increases acoustical noise and makes the voltage source inverter operated in high and variable switching frequency, requiring a high sampling frequency. In this paper, a simple effective ANN-based DTC of the induction machine is proposed. Neural networks with a simple architecture are designed and implemented in influential points of the direct torque control block of the three phase induction machine in order to improve its dynamic performance while preserving the DTC structure simplicity as much as possible. In particular, this paper proposes to reduce, on the one hand, the torque ripple and commutation frequency. Neural comparators are used to select the appropriate bandwidth for the torque and flux hysteresis controllers. Their aim is to optimize the ripple level in the developed torque and flux. On the other hand, a neural speed controller is designed in order to improve the system ability to respond rapidly to changes in process variables and mitigate the effects of external perturbations. The performance of the proposed control are tested in simulation and highlighted by comparing to the conventional DTC control based on conventional hysteresis comparators and conventional PI speed controller. The obtained results show the feasibility and good performances of the proposed control.

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On the viability of energy harvesting piezoelectric devices for supplemental power generation in uninhabited aircraft systems

On the viability of energy harvesting piezoelectric devices ...

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AIAA Modeling and Simulation Technologies Conference 2014

作者： Feiguel, Arnaud Ricks, Trenton M. McWilliams, Keith Lacy, Thomas E. Myers, Oliver Donohoe, J. Patrick Jha, Ratan Sullivan, Rani W. Department of Machines Mechanisms Systems French Institute of Advanced Mechanics Clermont-Ferrand France Department of Aerospace Engineering Mississippi State University Mail Stop 9549 MSMS 39762 United States Department of Mechanical Engineering Mississippi State University Mail Stop 9549 MSMS 39762 United States Department of Electrical and Computer Engineering Mississippi State University Mail Stop 9549 MSMS 39762 United States Raspet Flight Research Laboratory Mississippi State University 114 Airport Rd StarkvilleMSMS 39762 United States Department of Aerospace Engineering Mississippi State University Mail Stop 9549 MSMS 39762 United States

ISBN: (数字)9781624103186

ISBN: (纸本)9781624102974

In this work, a global air vehicle finite element model employing empirically determined cyclic loads is used to assess the viability of energy harvesting piezoelectric devices for supplemental power generation in lightweight uninhabited aircraft systems (UASs) where the "Owl" all-composite ultralight UAS is used as a candidate proof-of-concept platform. The Owl was developed at the Mississippi State University Raspet Flight Research laboratory as part of the U.S. Army Space Missile Defense Command High Performance Materials/Processes (HIPERMAP) Program. In the HIPERMAP flight test program, strain-time histories were recorded at key locations throughout the wing and fuselage. These measured strains were used in the investigation of practical implementation of energy harvesting piezoelectric materials within the Owl UAS with the intent of harvesting electrical power from structural oscillations of the wings during operation. The total power generated was determined from a 80 KIAS 4G pullup maneuver, where piezoelectric patches were simulated in the span-wise direction along the inner surfaces of the upper and lower skins of both wings. The energy harvesting capability of the Owl UAS was insufficient due to the small oscillation frequency and low strain magnitudes of the wing during flight. Nevertheless, such energy harvesting devices remain promising for microscale UASs where power requirements are lower and the oscilation frequency of the wings is higher. © 2014 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

关键词： Piezoelectricity

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Design of Small-Area Transimpedance Optical Receiver Module for Optical Interconnects

Design of Small-Area Transimpedance Optical Receiver Module ...

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International Conference on Advanced Communication Technology

作者： Jamshid Sangirov Ikechi Augustine Ukaegbu Nga T. H. Nguyen Tae-Woo Lee Mu-Hee Cho Hyo-Hoon Park Photonic Computer Systems Laboratory Electrical Engineering Department KAIST Daejeon Korea 305-701

ISBN: (纸本)9781479932177

The development and miniaturization of electronic devices and components is pushing the system devices and their interconnecting interfaces to become even smaller. Thus, reducing the size of receiver (Rx) and transmitter (Tx) chips plays an plays an important role in designing a small-size optical modules utilized in o/e and e/o converters. Therefore, designing a small-area optical Rx may require intuitive solutions, such as building single-ended Rx and utilizing some of the advantages of differential Rx. Optical Rx should convert optical input signal to voltage output signal and provide sufficient gain and frequency operation for feeding to subsequent blocks including clock and data recovery circuit (CDR) and/or Serializer and Deserializer (SerDes). Therefore, we have designed a small-area transimpedance optical receiver (TIORx) using regulated-cascode (RGC) as an input stage which converts input photocurrent to voltage signal. The RGC block is connected to post amplifying stages to increase the overall transimpedance gain of the TIORx. The post amplifying gain stages utilizes two intersecting active feedback in order to increase the frequency operation in addition to increasing the gain of the proposed TIORx chip. The TIORx module is designed in a 0. 13μm CMOS technology and works up to 10 Gbps data rate. The TIORx chip core occupies an area of 0.051mm~2 with power consumption of 16.9 mW at 1.3 V. A measured 3-dB bandwidth of 6.9 GHz was obtained for the TIORx module with a transimpedance gain of 60 dB?.

关键词： Optical receiver small-area circuit design bandwidth improvement optical interconnections

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DIV： Dynamic Integrity Validation Framework for Detecting Compromises on Virtual Machine Based Cloud Services in Real Time

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China Communications 2014年第8期11卷 15-27页

作者： WANG Chunlu LIU Chuanyi LIU Bin DONG Yingfei School of Computer Science Beijing University of Posts and Telecommunications Beijing 100876 P. R. China School of Software Engineering Beijing University of Posts and Telecommunications Beijing 100876 P. R. China Key Laboratory of Trustworthy Distributed Computing and Service (BUPT) Ministry of Education Beijing 100876 P. R. China Department of Electrical Engineering University of Hawaii Honolulu Hawaii U.S.

with the increasing popularity of cloud services,attacks on the cloud infrastructure also increase ***,how to monitor the integrity of cloud execution environments is still a difficult *** this paper,a real-time dynamic integrity validation(DIV) framework is proposed to monitor the integrity of virtual machine based execution environments in the *** can detect the integrity of the whole architecture stack from the cloud servers up to the VM OS by extending the current trusted chain into virtual machine's architecture *** introduces a trusted third party(TTP) to collect the integrity information and detect remotely the integrity violations on VMs periodically to avoid the heavy involvement of cloud tenants and unnecessary information leakage of the cloud *** evaluate the effectiveness and efficiency of DIV framework,a prototype on KVM/QEMU is implemented,and extensive analysis and experimental evaluation are *** results show that the DIV can efficiently validate the integrity of files and loaded programs in real-time,with minor performance overhead.

关键词： cloud security remote attestation trusted computing cloud trustworthiness

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Triple grouping and period-three oscillations in minority-game dynamics

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Physical Review E 2014年第6期90卷 062917-062917页

作者： Jia-Qi Dong Zi-Gang Huang Liang Huang Ying-Cheng Lai Institute of Computational Physics and Complex Systems Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou University Lanzhou 730000 China School of Electrical Computer and Energy Engineering Arizona State University Tempe Arizona 85287 USA Department of Physics Arizona State University Tempe Arizona 85287 USA

Dynamical systems based on the minority game (MG) have been a paradigm for gaining significant insights into a variety of social and biological behaviors. Recently, a grouping phenomenon has been unveiled in MG systems of multiple resources (strategies) in which the strategies spontaneously break into an even number of groups, each exhibiting an identical oscillation pattern in the attendance of game players. Here we report our finding of spontaneous breakup of resources into three groups, each exhibiting period-three oscillations. An analysis is developed to understand the emergence of the striking phenomenon of triple grouping and period-three oscillations. In the presence of random disturbances, the triple-group/period-three state becomes transient, and we obtain explicit formula for the average transient lifetime using two methods of approximation. Our finding indicates that, period-three oscillation, regarded as one of the most fundamental behaviors in smooth nonlinear dynamical systems, can also occur in much more complex, evolutionary-game dynamical systems. Our result also provides a plausible insight for the occurrence of triple grouping observed, for example, in the U.S. housing market.

关键词： DIFFERENTIAL equations -- Oscillation theory FLUCTUATIONS (Physics) OSCILLATIONS HOUSING market HOUSING -- Finance

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A Framework to Analyze Processor Architectures for Next-Generation On-Board Space computing

A Framework to Analyze Processor Architectures for Next-Gene...

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IEEE Aerospace Conference

作者： Tyler M. Lovelly Donavon Bryan Kevin Cheng Rachel Kreynin Alan D. George Ann Gordon-Ross Gabriel Mounce NSF Center for High-Performance Reconfigurable Computing (CHREC) Department of Electrical and Computer Engineering University of Florida Gainesville FL USA Air Force Research Laboratory (AFRL) Space Vehicles Directorate Kirtland Air Force Base Albuquerque NM USA

ISBN: (纸本)9781479916191

Due to harsh and inaccessible operating environments, space computing presents many unique challenges with respect to stringent power, reliability, and programmability constraints that limit on-board processing performance and mission capabilities. However, the increasing need for real-time sensor and autonomous processing, coupled with limited communication bandwidth with ground stations, are increasing the demand for high-performance, on-board computing for next-generation space missions. Since currently available radiation-hardened space processors cannot satisfy this growing demand, research into various processor architectures is required to ensure that potential new space processors are based on architectures that will best meet the computing needs of space missions. To enable this research, we present a novel framework to analyze potential processor architectures for space computing. By using this framework to analyze a wide range of existing radiation-hardened and emerging commercial processors, tradeoffs between potential space computing architectures can be determined and considered when designing new space processors or when selecting commercial architectures for radiation hardening and use in space missions. We demonstrate the ability of the framework to generate data for various architectures in terms of performance and power, and analyze this data for initial insights into the effects of processor architectures on space mission capabilities. The framework provides a foundation for the analysis of a broad and diverse set of processor architectures for potential use in next-generation, on-board space computing.

关键词： computing foundation capabilities Processor Architectures astronautical mission Radiation hardening ARCHITECTURE Foundations Frameworks PROCESSOR Electric power reliability foundation analysis

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Message from the demonstrations chair

Proceedings - Conference on Local Computer Networks, LCN

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Proceedings - Conference on Local computer Networks, LCN 2014年

作者： Akkaya, Kemal Aust, Stefan Hollick, Matthias Itaya, Satoko Kantarci, Burak Pfeiffer, Tom Senel, Fatih Strayer, Tim Andersson, Karl Southern Illinois University United States NEC Communication Systems Ltd. Japan TU Darmstadt Germany Smart Wireless Laboratory NICT Japan University of Ottawa Canada TU Berlin Germany International Antalya University Turkey BBN Technologies United States Pervasive and Mobile Computing Laboratory Department of Computer Science Electrical and Space Engineering Luleå University of Technology Sweden

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Finding tree symmetries using continuous-time quantum walk

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Chinese Physics B 2013年第5期22卷 124-131页

作者：吴俊杰张百达唐玉华强晓刚会权 State Key Laboratory of High Performance Computing National University of Defense Technology School of Computer National University of Defense Technology Center for Quantum Photonics H. H. Wills Physics Laboratory and Department of Electrical and Electronic EngineeringUniversity of Bristol

Quantum walk, the quantum counterpart of random walk, is an important model and widely studied to develop new quantum algorithms. This paper studies the relationship between the continuous-time quantum walk and the symmetry of a graph, especially that of a tree. Firstly, we prove in mathematics that the symmetry of a graph is highly related to quantum walk. Secondly, we propose an algorithm based on the continuous-time quantum walk to compute the symmetry of a tree. Our algorithm has better time complexity O（N3） than the current best algorithm. Finally, through testing three types of 10024 trees, we find that the symmetry of a tree can be found with an extremely high efficiency with the help of the continuous-time quantum walk.

关键词： quantum walk tree symmetry automorphism

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Continuous-variable measurement-device-independent quantum key distribution

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Physical Review A 2014年第5期89卷 052301-052301页

作者： Zhengyu Li Yi-Chen Zhang Feihu Xu Xiang Peng Hong Guo State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science and Center for Quantum Information Technology Peking University Beijing 100871 China Center for Computational Science and Engineering Peking University Beijing 100871 China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing 100876 China Centre for Quantum Information and Quantum Control Department of Physics and Department of Electrical and Computer Engineering University of Toronto Toronto Ontario Canada M5S 3G4

We propose a continuous-variable measurement-device-independent quantum key distribution (CV-MDI QKD) protocol, in which detection is conducted by an untrusted third party. Our protocol can defend all detector side channels, which seriously threaten the security of a practical CV QKD system. Its security analysis against arbitrary collective attacks is derived based on the fact that the entanglement-based scheme of CV-MDI QKD is equivalent to the conventional CV QKD with coherent states and heterodyne detection. We find that the maximal total transmission distance is achieved by setting the untrusted third party close to one of the legitimate users. Furthermore, an alternate detection scheme, a special application of CV-MDI QKD, is proposed to enhance the security of the standard CV QKD system.

关键词： QUANTUM theory QUANTUM mechanics QUANTUM entanglement QUANTUM coherence HETERODYNE detection QUANTUM fluctuations

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Symptom selection for multi-label data of inquiry diagnosis in traditional Chinese medicine

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Science China(Information Sciences) 2013年第5期56卷 238-250页

作者： SHAO Huan LI GuoZheng LIU GuoPing WANG YiQin School of Computer Engineering and Science Shanghai University Department of Control Science and Engineering Key Laboratory of Ministry of Education for Service Computing and Embedded SystemsTongji University Laboratory of Information Access and Synthesis of TCM Four Diagnosis Shanghai University of Traditional Chinese Medicine

In traditional Chinese medicine(TCM) diagnosis,a patient may be associated with more than one syndrome tags,and its computer-aided diagnosis is a typical application in the domain of multi-label learning of high-dimensional *** is common that a great deal of symptoms can occur in traditional Chinese medical diagnosis,which affects the modeling of diagnostic *** selection entails choosing the smallest feature subset of relevant symptoms,and maximizing the generalization performance of the *** present there are rare researches on feature selection on multi-label data.A hybrid optimization technique is introduced to symptom selection for multi-label data in TCM diagnosis in this paper,and modeling is made by means of four multi-label learning algorithms like k nearest neighbors,*** compare the performance of the algorithm with the current popular dimension reduction algorithms like MEFS(embedded feature selection for multi-Label learning),MDDM(multi-label dimensionality reduction via dependence maximization) on the UCI Yeast gene functional data set and an inquiry diagnosis dataset of coronary heart disease(CHD).Experimental results show that the algorithm we present has significantly improved the *** particular,the improvement on the average precision for the classifier is up to 10.62% and 14.54%.Syndrome inquiry modeling of CHD in TCM is realized in this paper,providing effective reference for the diagnosis of CHD and analysis of other multi-label data.

关键词： multi-label learning feature selection high-dimensionality inquiry of traditional Chinese medicine coronary heart disease

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