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arXiv 2018年

作者： Snow, B. Fedun, V. Gent, F.A. Verth, G. Erdélyi, R. School of Mathematics and Statistics University of Sheéld S3 7RH United Kingdom Department of Automated Control and Systems Engineering University of Sheéld S1 3JD United Kingdom Department of Computer Science ReSoLVE Centre of Excellence Aalto University PO Box 15400 HelsinkiFI-00076 Finland Dept. of Astronomy Eötvös L. University Pazmany Peter sétány 1/A BudapestH-1117 Hungary

Vortex motions are frequently observed on the solar photosphere. These motions may play a key role in the transport of energy and momentum from the lower atmosphere into the upper solar atmosphere, contributing to coronal heating. The lower solar atmosphere also consists of complex networks of ux tubes that expand and merge throughout the chromosphere and upper atmosphere. We perform numerical simulations to investigate the behaviour of vortex driven waves propagating in a pair of such ux tubes in a non-force-free equilibrium with a realistically modelled solar atmosphere. The two ux tubes are independently perturbed at their footpoints by counter-rotating vortex motions. When the ux tubes merge, the vortex motions interact both linearly and nonlinearly. The linear interactions generate many small-scale transient magnetic substructures due to the magnetic stress imposed by the vortex motions. Thus, an initially monolithic tube is separated into a complex multi-threaded tube due to the photospheric vortex motions. The wave interactions also drive a superposition that increases in amplitude until it exceeds the local Mach number and produces shocks that propagate upwards with speeds of approximately 50 km s1. The shocks act as conduits transporting momentum and energy upwards, and heating the local plasma by more than an order of magnitude, with peak temperature approximately 60;000 K. Therefore, we present a new mechanism for the generation of magnetic waveguides from the lower solar atmosphere to the solar corona. This wave guide appears as the result of interacting perturbations in neighbouring ux tubes. Thus, the interactions of photospheric vortex motions is a potentially significant mechanism for energy transfer from the lower to upper solar atmosphere. Copyright © 2018, The Authors. All rights reserved.

关键词： Magnetohydrodynamics

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Electron wave packet evolution under the influence of random electric field

Electron wave packet evolution under the influence of random...

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International Conference on Mathematical Methods in Electromagnetic Theory (MMET)

作者： D.I. Kulik S.I. Pavlik Yu.S. Oseledchik Department of Automated Systems of Process Control Zaporizhzhya State Engineering Academy Zaporizhzhya Ukraine Department of Automated Systems of Process Control Zaporizhzhya State Engineering Academy Ukraine

ISBN: (纸本)9781509019571

We consider an electron wave packet evolution in the external deterministic electric field with Gaussian white noise addition. An explicit expression was given for the averaged probability flux with Gaussian initial wave function. We show that the noise addition increases wave packet spreading rate, which has a significant influence on flux amplitude and may play both destructive and constructive role. This depends on the form of external deterministic field.

关键词： Electric fields Wave functions Electric potential Schrodinger equation Fourier transforms

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Nonequilibrium Green's function method for the harmonic oscillator in a heat bath

Nonequilibrium Green's function method for the harmonic osci...

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International Young Scientists Forum on Applied Physics (YSF)

作者： S.I. Pavlik D.I. Kulik Yu.S. Oseledchik Department of Automated Systems of Process Control Zaporizhzhya State Engineering Academy Zaporizhzhya Ukraine

Using the nonequilibrium Green's function method, the problem of thermal relaxation of systems interacting with a heat bath is investigated. We apply this method to the harmonic oscillator interacting with a heat bath which consists of many harmonic oscillators. Using with the Keldysh nonequilibrium Green function technique we derive expressions for the the absorption and emission spectra. We also establish a connection to the the solution of the Heisenberg equation based on a fully quantum-mechanical Hamiltonian.

关键词： Oscillators Green's function methods Heating Harmonic analysis Absorption Mathematical model Physics

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Application of the tuning algorithm with the least squares approximation to the suboptimal control algorithm for integrating objects

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Journal of Physics: Conference Series 2017年第1期891卷

作者： V F Kuzishchin E I Merzlikina Hoang Van Va Department of Automated Control Systems for Thermal Processes Moscow Power Engineering Institute – National Research University Moscow Krasnokazarmennaya 14 Russia 111250.

The problem of PID and PI-algorithms tuning by means of the approximation by the least square method of the frequency response of a linear algorithm to the sub-optimal algorithm is considered. The advantage of the method is that the parameter values are obtained through one cycle of calculation. Recommendations how to choose the parameters of the least square method taking into consideration the plant dynamics are given. The parameters mentioned are the time constant of the filter, the approximation frequency range and the correction coefficient for the time delay parameter. The problem is considered for integrating plants for some practical cases (the level control system in a boiler drum). The transfer function of the suboptimal algorithm is determined relating to the disturbance that acts in the point of the control impact input, it is typical for thermal plants. In the recommendations it is taken into consideration that the overregulation for the transient process when the setpoint is changed is also limited. In order to compare the results the systems under consideration are also calculated by the classical method with the limited frequency oscillation index. The results given in the paper can be used by specialists dealing with tuning systems with the integrating plants.

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Implementation of Image Processing Algorithms Based on GPU

Implementation of Image Processing Algorithms Based on GPU

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International Scientific and Technical Conference on Computer Science and Information Technologies

作者： Ivan Tsmots Oleh Berezkyi Ihor Ihnatiev Iryna Gumovska Automated control systems Department Lviv Polytechnic National University Computer Engineering Department Ternopil National Economic University Department of Foreign Languages and Professional Communication Ternopil National Economic University

ISBN: (纸本)9781509027415

The most perspective direction in the image processing became the use of graphics processing units (GPU). The main advantage of it is the exceptional dedication to work with 2d and 3d graphics, respectively processing large volumes of similar data. The consequence of this was the emergence of a single graphics card on the board of several stream processors responsible for performing the same type of command. However, a major breakthrough in the use of the GPU is the emergence of the possibility of programming the stream processors (vertex and pixel) image processing. The special feature of the group of processors are parallel processing, i.e., for a pixel processor unit is one piece or texel. For example, modern GPU carry on board more than 1,000 stream processors, each type of which can significantly improve performance by parallel use of all processors. Work related to the parallelization takes on the GPU, the engineer must identify only the basic algorithm for a single processor.

关键词： Neural oriented computer system An integrated approach Principles Structure Specialized module algorithm CUDA

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On the matter of the reliability of the chemical monitoring system based on the modern control and monitoring devices

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Journal of Physics: Conference Series 2017年第1期891卷

作者： A V Andriushin N S Dolbikova S V Kiet E I Merzlikina I S Nikitina Department of Automated Control Systems for Thermal Processes Moscow Power Engineering Institute – National Research University Moscow Krasnokazarmennaya 14 111250 Russia OOO NPP Tehnopribor Liubertsy Oktyabrskiy prospekt 112 140002 Russia Department of Water and Fuel Technologies Moscow Power Engineering Institute – National Research University Moscow Krasnokazarmennaya 14 111250 Russia

The reliability of the main equipment of any power station depends on the correct water chemistry. In order to provide it, it is necessary to monitor the heat carrier quality, which, in its turn, is provided by the chemical monitoring system. Thus, the monitoring system reliability plays an important part in providing reliability of the main equipment. The monitoring system reliability is determined by the reliability and structure of its hardware and software consisting of sensors, controllers, HMI and so on [1,2]. Workers of a power plant dealing with the measuring equipment must be informed promptly about any breakdowns in the monitoring system, in this case they are able to remove the fault quickly. A computer consultant system for personnel maintaining the sensors and other chemical monitoring equipment can help to notice faults quickly and identify their possible causes. Some technical solutions for such a system are considered in the present paper. The experimental results were obtained on the laboratory and experimental workbench representing a physical model of a part of the chemical monitoring system.

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Production Planning and Opportunistic Preventive Maintenance for Unreliable One-Machine Two-Products Manufacturing systems

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IFAC-PapersOnLine 2015年第3期48卷 478-483页

作者： Assid, M. Gharbi, A. Hajji, A. Automated Production Engineering Department École de Technologie Supérieure Production System Design and Control Laboratory University of Québec 1100 Notre Dame Street West Montreal QC H3C 1K3 Canada Department of Operations and Decision Systems CIRRELT Pavillon Palasis-Prince 2325 rue de la Terrasse Quebec QC G1V 0A6 Canada

This paper develops an effective joint production, setup and maintenance control policies in an unreliable one-machine two-products manufacturing system. The main objective is to reach a higher synchronization level of the preventive maintenance (PM) interventions in the planning of production activities. The proposed joint control policy integrates the concept of the opportunistic maintenance by taking advantage of the machine stoppage during setup operations in order to conduct preventive actions. This aims to increase the machine availability and to reduce the risk of shortages. Performance evaluation of the proposed control policy is carried out using a combined continuous/discrete event simulation model. It is subsequently analyzed by statistical techniques of optimization such as design of experiments, analysis of variance and response surface methodology. An illustrative numerical example followed by an in-depth comparison study for a wide range of the system configurations are performed in order to demonstrate the usefulness and the robustness of the results. © 2015, IFAC (International Federation of Automatic control) Hosting by Elsevier Ltd. All rights reserved.

关键词： Production control

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Dynamics of a 9-DoF Robotic Leg for a Football Simulator

Dynamics of a 9-DoF Robotic Leg for a Football Simulator

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RSI/ISM International Conference on Robotics and Mechatronics

作者： Masoud Vahidi S. Ali A. Moosavian Center of Excellence in Robotics and Control Advanced Robotics and Automated Systems (ARAS) Lab. Department of Mechanical Engineering K.N. Toosi University of Technology Tehran Iran

ISBN: (纸本)9781467372350

This paper focuses on a robotic human-like leg. This robot was designed and modeled for task of kicking soccer ball to desired target. In addition, applications of this robot have been explained and its kinematics and dynamics equations have been developed. Kinematic analysis has been done using Denavit-Hartenberg method and position, velocity and acceleration of center of mass (CoM) of all links can be obtained. Dynamics equations of this robot have been written using recursive Lagrange method and inverse dynamics problem has been solved. Finally, kinematics and dynamics equations of this robot are verified using a numerical simulation in MATLAB simmechanics.

关键词： robotic leg simmechanics verification kinematics dynamics

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Time Optimized Digital Image Processing of Ball and Plate System Using Artificial Neural Network

Time Optimized Digital Image Processing of Ball and Plate Sy...

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RSI/ISM International Conference on Robotics and Mechatronics

作者： Yasaman Parandian Hannaneh Z. Arabshahi Ali Nasr S. Ali A. Moosavian Center of Excellence in Robotics and Control Advanced Robotics and Automated Systems (ARAS) Lab. Department of Mechanical Engineering K.N. Toosi University of Technology Tehran Iran

ISBN: (纸本)9781467372350

Regarding robot interaction with moving objects and the necessity for robot controller to react in a timely manner having the objects current position, finding an efficient positioning method has always been a challenge. As ball and plate system is considered to be a standard experimental system in control laboratories. The system is consisted of the following pieces: a horizontal plate which gets tilted along each horizontal axes. The ball, which is located on the plate;is controlled by the system in a way to be placed in any point on the plate. In fact, the ball and plate system is an extension of the classical ball on beam experiment that is often used to study various types of control and stability problems.

关键词： Forward Kinematics Neural Networks Real-Time Computer Vision 3RRS Parallel Robot Ball and Plate

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CPG-Based Gait Transition of a Quadruped Robot

CPG-Based Gait Transition of a Quadruped Robot

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RSI/ISM International Conference on Robotics and Mechatronics

作者： Farhad Asadi Mahdi Khorram S. Ali A. Moosavian Center of Excellence in Robotics and Control Advanced Robotics & Automated Systems (ARAS) Lab Department of Mechanical Engineering K. N. Toosi University of Technology Tehran Iran

ISBN: (纸本)9781467372350

Quadruped animals have high agility and grace skills in the motion over natural environment. An important feature of such animals is their abilities in the selection of appropriate gait in the response to the terrain irregularities and also the smooth transition between them in order to increase the stability or conserve the energy. In this paper, a Cartesian CPG-based controller for the gait generation and the transition between them will be developed. The proposed approach uses nonlinear coupled oscillators for generating rhythmic signals. These patterns can be modulated by a programmed excitation signal and proportionally changing the frequency, amplitude and the coupling parameters among oscillators. According to these variations, the step length, duration of swing and stance phases of all legs, relative phase between the legs and the sequence of leg lifting can be adjusted smoothly especially by the duration of gait transition. Then, trajectories of swing legs along the z- and x-axeis will be computed through the data obtained form the CPG controller. The reference ZMP path will be desgined on the basis of the footprints of legs. Then, the COG trajectories will be calculated with a preview servo controller. Finally, some simulations are conducted to verify the effectiveness of the proposed approach both in the gait generation and smooth gait transition for a quadruped robot.

关键词： central pattern generator Gait transition Walking and Trotting gait quadruped robots Pattern gait generation

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