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Disrupted bandcount doubling in an AC-DC boost PFC circuit modeled by a time varying map

Journal of Physics: Conference Series 2016年第1期692卷

作者： Viktor Avrutin Zhanybai T. Zhusubaliyev Abdelali El Aroudi Danièle Fournier-Prunaret Germain Garcia Erik Mosekilde Institute for Systems Theory and Automatic Control University of Stuttgart Stuttgart Germany Department of Computer Science Southwest State University Kursk Russia Department of Electronics Electrical Engineering Automatic Control Universitat Rovira i Virgili Tarragona Spain INSA LAAS-CNRS Université de Toulouse Toulouse France INSA LAAS-CNRS Université de Toulouse Toulouse France Department of Physics The Technical University of Denmark Lyngby Denmark

Power factor correction converters are used in many applications as AC-DC power supplies aiming at maintaining a near unity power factor. Systems of this type are known to exhibit nonlinear phenomena such as sub-harmonic oscillations and chaotic regimes that cannot be described by traditional averaged models. In this paper, we derive a time varying discretetime map modeling the behavior of a power factor correction AC-DC boost converter. This map is derived in closed-form and is able to faithfully reproduce the system behavior under realistic conditions. In the chaotic regime the map exhibits a sequence of bifurcation similar to a bandcount doubling cascade on the low frequency. However, the observed scenario appears in some sense incomplete, with some gaps in the bifurcation diagram, whose appearance to our knowledge has never been reported before. We show that these gaps are caused by high frequency oscillations.

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The soft robotics approach

SpringerBriefs in Applied Sciences and Technology

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SpringerBriefs in Applied Sciences and Technology 2014年第9783319039572期18卷 31-61页

作者： Freni, Pierluigi Botta, Eleonora Marina Randazzo, Luca Ariano, Paolo Applied Science and Technology Polytechnic University of Turin Turin Italy Mechanical Engineering McGill University Montreal Canada Control and Computer Engineering Polytechnic University of Turin Turin Italy Center for Space Human Robotics Italian Institute of Technology Turin Italy

ISBN: (纸本)9783319015644

Starting from the user’s requirements previously defined, a new soft robotics approach was chosen and developed in order to overcome the criticalities arisen in the analysis of the state of the art. One of the key points of soft robotics is biomimicry: in place of heavy, rigid and noisy motors, artificial muscles are in charge of the movement of the soft structure, allowing a number of degrees of freedom unthinkable with traditional mechanics. The shift from hard to soft robotics brings the focus on materials: actuating and sensing devices are embedded in the material itself, which turns out to be smart. In particular, the attention was focused on Electroactive Polymers (EAPs): these polymeric materials work as transducers, converting electrical inputs into mechanical outputs, and vice versa. After an extensive material selection procedure among all the EAPs solutions currently available, Dielectric Elastomers (DEs) emerged as the most suitable materials for the intended application and a mathematical model of their electro-mechanical behavior is presented. The control of the hand exoskeleton is addressed in this section. Its objective is to help the astronaut accomplish the tasks he has to perform. The entire control system is composed of four phases: the recognition of the astronaut’s will (detect and distinguish the different movements), the control strategy, the enhancement of these movements and the measure of the actual position and force. The final measure system was implemented focusing on redundancy, safety control and to assure minimum performances also in off-nominal conditions. © The Author(s) 2014.

关键词： Degrees of freedom (mechanics)

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State of the art

SpringerBriefs in Applied Sciences and Technology

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SpringerBriefs in Applied Sciences and Technology 2014年第9783319039572期18卷 17-29页

ISBN: (纸本)9783319015644

In this chapter we wrap up our literature investigation, pointing out the key focuses and requirements to be considered. We will go through our evaluations upon actuators, sensors, control systems and we will present some designs examples. Although literature is rich in studies on limbs exoskeletons aimed to several target applications, (such as rehabilitation, function restoring and virtual reality), the stringent requisites of EVA make most of the actuation and sensing solutions unsuitable for our device. Safety reasons and pressurization of the space suit force to avoid modern actuation technologies (i.e. air muscles), and focus on traditional motors such as piezoelectric ones. For what concerns sensors and control systems, most of the currently developed exoskeletons use physiological signals and are based on Electroencefalography (EEG) and on Electromyograpy (EMG). In the latter case, a big advantage is due to the fact that input signals are picked up directly from the motor units involved in the hand control. In the next pages we also present several examples of exoskeletons, including a pinching device for rehabilitation based on a cable mechanism, one finger device based on pulleys-lever structure, the four bar mechanism, a tendon system glove for function restoring and the EVAK-Glove from NASA. Finally, a couple of examples of feedback devices for medical applications are presented, integrating a variety of sensors, such as accelerometers, ultrasound, flow, pressure and vibration sensors, heat infrared camera, gyroscopes. © The Author(s) 2014.

关键词： NASA

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Concept layout

SpringerBriefs in Applied Sciences and Technology

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SpringerBriefs in Applied Sciences and Technology 2014年第9783319039572期18卷 63-84页

ISBN: (纸本)9783319015644

The chapter presents the design of the device actuators and sensors in terms of concept developing, dimensioning, testing and prototyping. Inspired by soft robotics concept, the design of actuators is based on the characteristics of dielectric elastomers and their relationship between voltage applied and material elongation. Smart material properties are exploited in the multiple layers actuator proposed, capable of performing both linear elongation and bending, by means of the application of different voltage levels to different layers. Calculations of the torques required by the hand actions and, consequently, the maximum stress are presented. Then, the choice of the material leads to the identification of the correct dimensioning of the system, in terms of voltage to be applied and thick of the actuator layers. In order to control the actuation according to the human will, sensors based on physiological signals are required. EMG and MMG based sensors are chosen, specifying the sensors number and positioning required for an effective human will identification. Pressure sensors, realized with dielectric elastomers, give the feedback of the system. Calculations relating voltage measured and pressure applied on the sensors are presented. Finally, the prototyping and testing phase is described, in which two mockup hands are realized for a proof of concept while EMG and MMG sensors are tested. Experimental setup and qualitative results are extensively described. © The Author(s) 2014.

关键词： Actuators

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Analysis and optimization of centralized sequential channel sensing in cognitive radio networks 20

Analysis and optimization of centralized sequential channel ...

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20th European Wireless Conference, EW 2014

作者： Shokri-Ghadikolaei, Hossein Yaghoubi, Forough Fischione, Carlo Automatic Control Department KTH Royal Institute of Technology Stockholm10044 Sweden School of Electrical and Computer Engineering College of Engineering University of Tehran Tehran Iran

ISBN: (纸本)9783800736218

Effective spectrum sensing strategies enable cognitive radios to enhance the spectrum efficiency. In this paper, modeling, performance analysis, and optimization of spectrum handoff in a centralized cognitive radio network are studied. More specifically, for a given sensing order, the average throughput of secondary users and average interference level among the secondary and primary users are evaluated for a cognitive radio network with only one secondary user. By a Markov chain analysis, a network with multiple secondary users performing cooperative spectrum sensing is modeled, and the above performance metrics are derived. Then, a maximization of the secondary network performance in terms of throughput while keeping under control the average interference is formulated. Finally, numerical results validate the analytical derivations and show that optimally tuning sensing time significantly enhances the performance of the spectrum handoff. Also, we observe that exploiting OR rule for cooperative spectrum sensing provides a higher average throughput compared to AND rule. © VDE VERLAG GMBH, Berlin, Offenbach, Germany.

关键词： Cognitive radio

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Economic load dispatch of power systems based on hysteretic noisy chaotic neural network

Economic load dispatch of power systems based on hysteretic ...

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2014 IEEE Workshop on Advanced Research and Technology in Industry Applications, WARTIA 2014

作者： Asun, Ming Cui, Shaojie Xu, Yaoqun Collage of Computer and Control Engineering Qiqihar University Qiqihar Heilongjiang Province China Institute of System Engineering Harbin University of Commerce Harbin Heilongjiang Province China

ISBN: (纸本)9781479969890

Hysteretic noisy chaotic neural network (HNCNN) has been proven to be a powerful tool in solving combinatorial optimization problems, which can increase the effective convergence toward optimal or near-optimal solutions by using both stochastic chaotic simulated annealing (SCSA) and hysteretic dynamics. Considering the excellent optimization performance of HNCNN, we apply HNCNN to better resolve economic load dispatch (ELD) of power system in this paper. In addition, the system loss and valve point effect are also involved in the simulation. Simulation results and analyses compared with other approaches are presented to illustrate efficiency of the HNCNN. © 2014 IEEE.

关键词： Stochastic systems

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A partial-state observer for a class of MIMO nonlinear systems 19

A partial-state observer for a class of MIMO nonlinear syste...

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19th IFAC World Congress on International Federation of Automatic control, IFAC 2014

作者： Wang, Lei Isidori, Alberto Su, Hongye Xu, Weihua State Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and Control ZheJiang University Hangzhou310027 China Department of Computer Control and Management Engineering University of Rome La Sapienza Rome Italy

ISBN: (纸本)9783902823625

In this paper, we consider input-affine invertible MIMO nonlinear systems which can be transformed into a special normal form by means of the structure algorithm. The normal form highlights a partial state, a subset of state variables, which plays in this setting a role similar to that of the outputs and its derivatives in a SISO system. It is shown that, if a system in this class can be asymptotically stabilized by means of a static feedback from that partial state, then semiglobal stabilization can be achieved via dynamic feedback driven by the output of the system. The dynamic feedback in question is based a (non-trivial) extension to MIMO systems of the standard high-gain observer. © IFAC.

关键词： Nonlinear systems

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Multi-sphere detection method using one-dimensional histogram and polytope method

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ICIC Express Letters 2014年第11期8卷 2985-2991页

作者： Nakashima, Shota Nakamoto, Hiroyuki Mu, Shenglin Kitazono, Yuhki Lu, Huimin Tanaka, Kanya Graduate School of Science and Engineering Yamaguchi University 2-16-1 Tokiwadai UbeYamaguchi Japan Department of Computer Science Nagoya Institute of Technology Nagoya Japan Electronic Control Engineering Department Hiroshima National College of Maritime Technology 4272-1 Higashino Osakikamijima-cho Toyota-gunHiroshima Japan Department of Electronic and Control Engineering Kitakyushu National College of Technology Kitakyushu Japan Department of Electrical Engineering and Electronics Kyushu Institute of Technology Sensui-cho Japan

A fast sphere extraction method is proposed in this paper. The proposed method utilizes the one-dimensional histogram as search space. The polytope method, which is one of the minimization algorithms, is employed for search parameters. The histogram has two characteristics. (a) The distribution of the histogram changes if the parameters of representing the sphere change. (b) The value of highest frequency of histogram becomes maximum if the best parameters are obtained. By employing the polytope method, the best parameters of sphere can be obtained when we get the highest frequency of histogram. The proposed method can extract the sphere from 3D vertex data without large memory space or long processing time.

关键词： Spheres

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On the regularization of generalized eigenvalues classifiers

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AIP Conference Proceedings 2016年第1期1776卷

作者： Mario R. Guarracino Mara Sangiovanni Gerardo Severino Gerardo Toraldo Marco Viola 1High Performance Computing and Networking Institute National Research Council of Italy - Naples Italy 2University of Naples Federico II Division of Agricultural Forest and Biosystems Engineering - Naples Italy 3University of Naples Federico II Department of Mathematics and Applications - Naples Italy 4Sapienza University of Rome Department of Computer Control and Management Engineering - Rome Italy

Generalized Eigenvalues Classifiers (GEC), which originated from the GEPSVM algorithm by Mangasarian, proved to be an efficient alternative to the Support Vector Machines (SVMs) in the solution of supervised classification tasks. However real-life datasets are often characterized by a large number of redundant features and by a great number of points whose labels are difficult (or too expensive) to assign. In this work we start from the Regularized Generalized Eigenvalue Classifier (ReGEC) and show how regularization terms can be used to enable the classifier to solve two different problems, strictly connected to that of supervised classification: feature selection and semi-supervised classification. Numerical results, obtained on some standard benchmark data sets, show the efficiency of the proposed solutions.

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Local and long-range transport influences on PM_(2.5) at a cities-cluster in northern China,during summer 2008

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Particuology 2014年第2期12卷 66-72页

作者： Lijie Gao Yingze Tian Caiyan Zhang Guoliang Shi Huize Hao Fang Zeng Chunli Shi Meigen Zhang Yinchang Feng Xiang Li State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and EngineeringNankai University Institute of Atmospheric Physics Chinese Academy of Sciences Department of Computer Science University of GeorgiaAthensGAUSA

Hourly PM2.5 concentrations were observed simultaneously at a cities-cluster comprising 10 cities/towns in Hebei province in China from July 1 to 31, 2008. Among the 10 cities/towns, Baoding showed the high- est average concentration level （161.57μg/m3） and Yanjiao exhibited the lowest （99.35 μg/m3 ）. These observed data were also studied using the joint potential source contribution function with 24-h and 72-h backward trajectories, to identify more clearly the local and countrywide-scale long-range transport sources. For the local sources, three important influential areas were found, whereas five important influential areas were defined for long-range transport sources. Spatial characteristics of PM2.5 were determined by multivariate statistical analyses. Soil dust, coal combustion, and vehicle emissions might be the potential contributors in these areas. The results of a hierarchical cluster analysis for back trajectory endpoints and PM2.s concentrations datasets show that the spatial characteristics of PM2.5 in the cities-cluster were influenced not only by local sources, but also by long-range transport sources. Different cities in the cities-cluster obtained different weighted contributions from local or long-range transport sources. Cangzhou, Shijiazhuang, and Baoding are near the source areas in the south of Hebei province, whereas Zhuozhou, Yangfang, Yanjiao, Xianghe, and Langfang are close to the sources areas near Beijing and Tianjin.

关键词： Local mtluenceRegional influenceJoint potential source contribution functionHierarchical cluster analysis

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