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2013 European Conference on Circuit Theory and Design, ECCTD 2013

作者： Nemes, Csaba Barcza, Gergely Nagy, Zoltan Legeza, Örs Szolgay, Peter Faculty of Information Technology Péter Pâzmâny Catholic University Budapest Hungary Cellular Sensory and Wave Computing Laboratory Computer and Research Automation Institute Hungarian Academy of Sciences Budapest Hungary Department of Theoretical Solid State Physics Wigner Research Centre for Physics Hungarian Academy of Sciences Budapest Hungary

ISBN: (纸本)9783000437854

Numerical analysis of strongly correlated quantum lattice models has a great importance in quantum physics. The exponentially growing size of the Hilbert space makes these computations difficult, however sophisticated algorithms have been developed to balance the size of the effective Hilbert space and the accuracy of the simulation. One of these methods is the density matrix renormalization group (DMRG) algorithm which has become the leading numerical tool in the study of low dimensional lattice problems of current interest. In the algorithm a high computational problem can be translated to a list of dense matrix operations, which makes it an ideal application to fully utilize the computing power residing in both current multi-core processors and novel kilo-processor architectures. © 2013 TU Dresden.

关键词： Economic and social effects

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Very short term pitch angle optimization in wind turbines: A machine learning approach

Very short term pitch angle optimization in wind turbines: A...

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International Conference on Power Engineering, Energy and Electrical Drives, POWERENG

作者： Mehmet Yesilbudak Ersan Kabalci Seref Sagiroglu Ilhami Colak Department of Electronics and Automation Vocational College of Haci Bektas Veli Nevsehir University Nevsehir Turkey Department of Electrical and Electronics Engineering Faculty of Engineering and Architecture Nevsehir University Nevsehir Turkey Department of Computer Engineering Faculty of Engineering Gazi University Ankara Turkey Department of Electrical and Electronics Engineering Faculty of Technology Gazi University Ankara Turkey

This paper proposes a pitch angle forecasting model based on the k-nearest neighbor classification. Air temperature, atmosphere pressure, wind direction, wind speed, rotor speed and wind power parameters were represented as a 6-dimensional attribute tuple in the forecasting model. Euclidean, Manhattan and Minkowski distance metrics for measuring the proximity between training and test tuples, mean absolute, mean absolute percentage, and normalized root mean square error metrics for measuring the forecasting accuracy were embedded into the forecasting model. The k-nearest neighbor classifier with Manhattan distance metric for k=1 achieved MAE, MAPE and NRMSE as 0.001°, 0.245% and 0.324%, respectively as the best forecasting accuracy. However, as the worst forecasting accuracy, MAE, MAPE and NRMSE were achieved as 0.015°, 3.236% and 2.613%, respectively for Minkowski distance metric and k=10.

关键词： Forecasting Measurement Wind turbines Predictive models Wind speed Atmospheric modeling Control systems

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Vibration signals processing by cellular automata for wind turbines intelligent monitoring

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Diagnostyka 2013年第2期14卷 31-36页

作者： Barszcz, Tomasz Bielecki, Andrzej Wójcik, Mateusz Department of Robotics and Mechatronics Faculty of Mechanical Engineering and Robotics AGH University of Science and Technology Al. Mickiewicza 30 30-059 Cracow Poland Department of Applied Computer Science Faculty of Electric Engineering Automation Computer Science and Biomedical Engineering AGH University of Science and Technology Al. Mickiewicza 30 30-059 Cracow Poland Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University Reymonta 4 30-059 Cracow Poland

In recent years wind energy is the fastest growing branch of the power generation industry. The largest cost for the wind turbine is its maintenance. A common technique to decrease this cost is a remote monitoring based on vibration analysis. Growing number of monitored turbines requires an automated way of support for diagnostic experts. As full fault detection and identification is still a very challenging task, it is necessary to prepare an early-warning tool, which would focus the attention on cases which are potentially dangerous. There were several attempts to develop such tools, in most cases based on various classification methods. The techniques that have been used so far are based on the vibration signals analysis in which the signals are considered as time series. However such approach has crucial limitations. Therefore, new approaches for wind turbines intelligent monitoring are worked out. Artificial intelligence systems are ones of promising. In this paper such approach is proposed - a vibration signal spectrum is considered as a pixel matrix which is processed using deterministic cellular automaton (DCA). It turns out that such processing allows us to detect pre-failure states.

关键词： Wind turbines

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Cascade PID control of some processes with distributed parameters through the (M pdx ) method with approximating solutions

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IFAC Proceedings Volumes 2013年第6期46卷 19-25页

作者： T. Coloşi M. Abrudean M.L. Ungureşan V. Mureşan Department of Automation Technical University of Cluj-Napoca Faculty of Automation and Computer Science 26-28 Gh. Baritiu Street 400027 Cluj-Napoca Romania Phone: +40-264-401240 +40-744-420906 Fax: +40-264-599893 Department of Physics and Chemistry Technical University of Cluj-Napoca Faculty of Materials Science and Engineering 103-105 Muncii Street 400641 Cluj-Napoca Romania Phone: +40-264-401627 Fax: +40-264-415054

Continuing the paper (2013) the analogical modeling and the numerical simulation of a cascade PID control diagram from Fig. 1 is presented, containing two distributed parameters processes, each one modeled through an equation with partial derivatives of second order with two independent variables. Through the numerical integration, the method of the Matrix of Partial Derivatives of the State Vector (M pdx ) is used too, associated with approximating solutions. The unitary and systemized character of this method is highlighted, considered known from the previous papers. (2009, 2011, 2013). Like in the case of paper [1], a program of numerical simulation for the entire PID cascade control scheme was elaborated, resulting a more complete phenomenological interpretation of the obtained results and performances.

关键词： equations with partial derivatives ordinary differential equations state vector initial conditions approximating solutions Taylor series cascade PID control scheme

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Complex Dynamical Behavior of a Two-Stage Colpitts Oscillator with Magnetically Coupled Inductors

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Journal of Chaos 2014年第1期2014卷

作者： V. Kamdoum Tamba H. B. Fotsin J. Kengne F. Kapche Tagne P. K. Talla Department of Physics Laboratory of Electronics and Signal Processing (LETS) Faculty of Science University of Dschang P.O. Box 67 Dschang *** Department of Telecommunication and Network Engineering IUT-Fotso Victor of Bandjoun University of Dschang P.O. Box 134 Bandjoun *** Department of Electrical Engineering Laboratory of Automation and Applied Computer (LAIA) IUT-Fotso Victor of Bandjoun University of Dschang P.O. Box 134 Bandjoun *** Department of Physics Laboratory of Mechanics and Modelling of Physical Systems (L2MPS) Faculty of Science University of Dschang P.O. Box 67 Dschang ***

A five-dimensional (5D) controlled two-stage Colpitts oscillator is introduced and analyzed. This new electronic oscillator is constructed by considering the well-known two-stage Colpitts oscillator with two further elements (coupled inductors and variable resistor). In contrast to current approaches based on piecewise linear (PWL) model, we propose a smooth mathematical model (with exponential nonlinearity) to investigate the dynamics of the oscillator. Several issues, such as the basic dynamical behaviour, bifurcation diagrams, Lyapunov exponents, and frequency spectra of the oscillator, are investigated theoretically and numerically by varying a single control resistor. It is found that the oscillator moves from the state of fixed point motion to chaos via the usual paths of period-doubling and interior crisis routes as the single control resistor is monitored. Furthermore, an experimental study of controlled Colpitts oscillator is carried out. An appropriate electronic circuit is proposed for the investigations of the complex dynamics behaviour of the system. A very good qualitative agreement is obtained between the theoretical/numerical and experimental results.

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2D Phononic Crystal Sensor with Normal Incidence of Sound

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Procedia Engineering 2011年 25卷 787-790页

作者： R. Lucklum M. Zubtsov M. Ke B. Henning U. Hempel Institute of Micro and Sensor Systems (IMOS) Otto-von-Guericke-University Magdeburg Germany Department of Physics Wuhan University Wuhan PR China Faculty of Electrical Engineering Computer Science and Mathematics University of Paderborn Germany Institute for Automation and Communication (ifak) Magdeburg Germany

This contribution shows the sensor application of a resonance-induced extraordinary transmission through a regular phononic crystal consisting of a metal plate with a periodic arrangement of holes in a square lattice at normal incidence of sound. The characteristic transmission peak has been found to strongly depend on liquid sound velocity. The respective peak maximum frequency can therefore serve as measure for liquid analysis. Experimental verification has been performed with mixtures of water and propanol as model system. Numerical calculations based on COMSOL and EFIT reveal more insides to the wave propagation characteristics. Experimental investigations with Schlieren method and laser interferometry support the theoretical findings.

关键词： Phononic crystal sensor Liquid sensor

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Determining liquid properties by extraordinary acoustic transmission through phononic crystals

Determining liquid properties by extraordinary acoustic tran...

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IEEE SENSORS

作者： R. Lucklum M. Zubtsov M. Ke A. Oseev U. Hempel B. Henning Institute of Micro and Sensor Systems (IMOS) Tto-von-Guericke-University Magdeburg Germany Department of Physics Wuhan University of China Wuhan China Institute of Automation and Communication (ifak) Magdeburg Germany Faculty of Electrical Engineering Computer Science and Mathematics University of Paderborn Paderborn Germany

ISBN: (纸本)9781424492909

This contribution shows how a resonance-induced extraordinary acoustic transmission through a phononic crystal structure can be used as sensor for liquid properties. The phononic crystal consists of a metal plate with a periodic array of holes. Ultrasound propagates in a way that the incidence direction of sound is perpendicular to the plate. A characteristic transmission peak has been found to strongly depend on liquid sound velocity. The respective peak maximum frequency serves as measure for liquid composition. Numerical calculations based on FDTD and FEA reveal more insides to the propagation characteristics, in particular the presence of specific plate modes. Experimental investigations using a laser vibrometer and the Schlieren method support the theoretical findings.

关键词： Acoustics Photonic crystals Frequency measurement Laser beams Crystals Time domain analysis Lattices

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Probabilistic Verification over GF(2m) Using Mod2-OBDDs

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Intelligent Information Management 2010年第2期2卷 95-103页

作者： J.L. Imana Department of Computer Architecture Faculty of Physics Complutense University

Formal verification is fundamental in many phases of digital systems design. The most successful verification procedures employ Ordered Binary Decision Diagrams (OBDDs) as canonical representation for both Boolean circuit specifications and logic designs, but these methods require a large amount of memory and time. Due to these limitations, several models of Decision Diagrams have been studied and other verification techniques have been proposed. In this paper, we have used probabilistic verification with Galois (or finite) field GF(2m) modifying the CUDD package for the computation of signatures in classical OBDDs, and for the construction of Mod2-OBDDs (also known as ?-OBDDs). Mod2-OBDDs have been constructed with a two-level layer of ?-nodes using a positive Davio expansion (pDE) for a given variable. The sizes of the Mod2-OBDDs obtained with our method are lower than the Mod2-OBDDs sizes obtained with other similar methods.

关键词： Verification Probabilistic OBDD Mod2-OBDD Galois Field GF(2m)

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A case study on benchmarking for biomedical engineering study programs

A case study on benchmarking for biomedical engineering stud...

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International Congress on Engineering Education

作者： Elsarnagawy, Tarek Alhelih, Eyad Farrag, Manal King Saud University Community College Applied Medical Department Saudi Arabia Prince Sultan University for Women CIS KSA Saudi Arabia Faculty of Informatics and Automation Institute for Theoretical and Technical Informatics Computer Architecture Technical University Ilmenau Germany

ISBN: (纸本)9781424473113

This study presents the experience of the department of Applied Medical Sciences (AMS) - Riyadh Community College - King Saud University in its way to achieve the international accreditation standards to ensure quality. The study is based on a three years experience (2008-2010). The following will be clarified, the list of criteria adopted by AMS to ensure quality and the procedures adopted by AMS to apply accreditation standards to ensure quality of *** study followed the iterative descriptive approach in analyzing the topics. The results show the procedures how the standards were applied to ensure the quality of outputs by meeting the requirements in all aspects, national and international, especially of the internationally recognized organization Council on Occupational Education COE, by which the AMS was then accredited in June 2010. A four year development strategic plan is set for the department to ensure consistent quality and improvement standards. By reviewing the literature of former experiences of Arab and international bodies for accreditation and quality assurance, the study concluded a list of accreditation criteria and indicators of quality assurance, as well as indicators to ensure the quality of the university environment. The achieved number of accreditation and quality assurance standards are presented from both national and international organizations and were found to be: 25 accreditation standards leading to 245 indicators, and 41 indicators for QA, and 29 indicators for the QA of the university *** study recommended the need to activate the academic accreditation and assessment of academic programs periodically internally and externally. Furthermore, similar departments of applied medical sciences should adopt the presented accreditation and quality assurance principles. In addition those departments are asked to put a strategic plan that meets their needs and goals. © 2010 IEEE.

关键词： Biomedical engineering

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Investigation of the spatial spectrum of cortical contours on cross-sections of the brain

Investigation of the spatial spectrum of cortical contours o...

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10th International Conference on Information Technology and Applications in Biomedicine: Emerging Technologies for Patient Specific Healthcare, ITAB 2010

作者： Graichen, Uwe Eichardt, Roland Güllmar, Daniel Haueisen, Jens Ilmenau University of Technology Faculty of Computer Science and Automation Institute of Biomedical Engineering and Informatics P.O. Box 100565 98684 Ilmenau Germany Jena University Hospital Department of Diagnostic and Interventional Radiology Medical Physics Group Philosophenweg 3 07743 Jena Germany

ISBN: (纸本)9781424465606

The human brain possesses a highly structured surface. A quantitative examination of the cortical surface is of particular interest for many questions, e.g. the investigation the relation between the spatial frequencies of cortical surfaces and spatial frequencies within Electroencephalogram and the analysis of changes of the structure of the human brain caused by diseases. In this paper a Fourier analysis approach to investigate the spatial spectrum of contour data of the cortical surface is introduced. The method was validated using artificial data with known spatial spectrum and employed to investigate the spatial frequencies of the cortical surface of a human subject. © 2010 IEEE.

关键词： Fourier analysis

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