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2018 International Conference on Materials and Energy, ICOME 2018

作者： Fernandez-Gamiz, Unai Ruiz De Loizaga, Jon Errasti, Iñigo Boyano, Ana Zulueta, Ekaitz Lopez-Guede, Jose Manuel Nuclear Engineering and Fluid Mechanics Dep. University of the Basque Country Nieves Cano 12 Vitoria-Gasteiz Araba01006 Spain Nieves Cano 12 Vitoria-Gasteiz01006 Spain Automatic control and System Engineering Dep. University of the Basque Country Nieves Cano 12 Vitoria-Gasteiz Araba01006 Spain

Vortex generators (VGs) are used increasingly more by the wind turbine manufacture industry as flow control devices to improve rotor blade aerodynamic performance. The VG height is usually designed with equal thickness of the local boundary layer at the VG position. Nevertheless, these conventional VGs may produce excess residual drag in some applications. The so-called sub boundary layer VGs can provide enough momentum transfer over a region several times their own height for effective flow-separation control with much lower drag. The main objective is to investigate how well the simulations can reproduce the physics of the flow of the primary vortex generated by a triangular VG mounted on a flat plate with negligible pressure gradient with the angle of attack of the vane to the oncoming flow β= 18. Three different device heights H= 5mm, H1= 6,25mm, H2= 4,16mm have been studied and compared both qualitatively and quantitatively. To that end, computational simulations have been carried out using RANS method and at Reynolds number Re = 2600 based on the boundary layer momentum thickness θ= 2.4 mm at the VG position. The computational results show good agreement with the experimental data available in AVATAR project. © The Authors, published by EDP Sciences, 2020.

关键词： Boundary layers

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Learning Based Model Predictive control for Quadcopters with Dual Gaussian Process

arXiv

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arXiv 2021年

作者： Liu, Yuhan Tóth, Roland The Harbin Institute of Technology Department of Control Science and Engineering Harbin China The Eindhoven University of Tech. Dep. of Electrical Eng. Control Systems Group Eindhoven Netherlands The Institute for Computer Science and Control Budapest Hungary

An important issue in quadcopter control is that an accurate dynamic model of the system is nonlinear, complex, and costly to obtain. This limits achievable control performance in practice. Gaussian process (GP) based estimation is an effective tool to learn unknown dynamics from input/output data. However, conventional GP-based control methods often ignore the computational cost associated with accumulating data during the operation of the system and how to handle forgetting in continuous adaption. In this paper, we present a novel Dual Gaussian Process (DGP) based model predictive control strategy that improves the performance of a quadcopter during trajectory tracking. The bio-inspired DGP structure is a combination of a long-term GP and a short-term GP, where the long-term GP is used to keep the learned knowledge in memory and the short-term GP is employed to rapidly compensate unknown dynamics during online operation. Furthermore, a novel recursive online update strategy for the short-term GP is proposed to successively improve the learnt model during online operation in an efficient way. Numerical simulations are used to demonstrate the effectiveness of the proposed strategy. © 2021, CC BY-NC-SA.

关键词： Model predictive control

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Transmission ratio design for electric vehicles via analytical modeling and optimization

arXiv

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arXiv 2020年

作者： Hofman, Theo Salazar, Mauro Control Systems Technology group Dep. of Mechanical Engineering Eindhoven University of Technology Netherlands

In this paper we present an effective analytical modeling approach for the design of the transmission of electric vehicles. Specifically, we first devise an analytical loss model for an electric machine and show that it can be accurately fitted by only sampling three points from the original motor map. Second, we leverage this model to derive the optimal transmission ratio as a function of the wheels’ speed and torque, and use it to optimize the transmission ratio. Finally, we showcase our analytical approach with a real-world case-study comparing two different transmission technologies on a BMW i3: a fixed-gear transmission (FGT) and a continuously variable transmission (CVT). Our results show that even for e-machines intentionally designed for a FGT, the implementation of a CVT can significantly improve their operational efficiency by more than 3%. The provided model will ultimately bridge the gap in understanding how to efficiently specify the e-machine and the transmission technology in an integrated fashion, and enable to effectively compare single- and multi-speed-based electric powertrains. Copyright © 2020, The Authors. All rights reserved.

关键词： Powertrains

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A dynamic programming approach to solving constrained linear-quadratic optimal control problems

arXiv

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arXiv 2019年

作者： Mitze, Ruth Mönnigmann, Martin Automatic Control and Systems Theory Dep. of Mechanical Engineering Ruhr-Universität Bochum Bochum44801 Germany

The solution of a constrained linear-quadratic regulator problem is determined by the set of its optimal active sets. We propose an algorithm that constructs this set of active sets for a desired horizon N from that for horizon N − 1. While it is not obvious how to extend the optimal feedback law itself for horizon N − 1 to horizon N, a simple relation between the optimal active sets for two successive horizon lengths exists. Specifically, every optimal active set for horizon N is a superset of an optimal active set for horizon N − 1 if the constraints are ordered stage by stage. The stagewise treatment results in a favorable computational effort. In addition, it is easy to detect the solution of the current horizon is equal to the infinite-horizon solution, if such a finite horizon exists, with the proposed algorithm. Copyright © 2019, The Authors. All rights reserved.

关键词： Quadratic programming

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A bibliometric analysis of technology management research at PICMET for 2009-2018

A bibliometric analysis of technology management research at...

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2019 Portland International Conference on Management of engineering and Technology, PICMET 2019

作者： Cetindamar, D. Kocaoglu, D. Lammers, T. Merigo, J.M. School of Information Systems and Modelling Faculty of Engineering and Information Technology University of Technology Sydney Sydney Australia Engineering and Technology Management Department Portland State University PortlandOR United States Dep. of Management Control and Information Systems School of Economics and Business University of Chile Santiago Chile

ISBN: (纸本)9781890843403

The Portland International Centre for Management of engineering and Technology (PICMET) was established in 1989. It has since become one of the leading organizations in the field of management of engineering and technology in the world. PICMET provides a strong platform for academicians, industry professionals and government representatives to exchange new knowledge derived from both research and implementation of technology management. To celebrate its 30-year journey, and to show the trends in technology management research and implementation over the past ten years (2009-2018), this paper presents a bibliometric analysis of the more than 3000 papers accepted for inclusion in PICMET conferences. The study highlights the topics, authors, journals and countries where significant research on technology management is conducted. © 2019 PICMET.

关键词： Knowledge management

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High stiffness fixation and thermal insulation in a superconducting planar motor 18

High stiffness fixation and thermal insulation in a supercon...

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18th International Conference of the European Society for Precision engineering and Nanotechnology, EUSPEN 2018

作者： Koolmees, H.B. Vermeulen, J.P.M.B. Eindhoven University of Technology Dep. of Mechanical Engineering Control Systems Technology - Mechatronic Systems Design Netherlands

ISBN: (纸本)9780995775121

A superconducting planar motor is being investigated to provide higher acceleration potential compared to existing planar motors. Currently used permanent magnets are replaced by superconducting electromagnets, at a temperature below 20 K, providing a higher magnetic field density. Fixation of superconductors is a challenge due to the requirements on stiffness and thermal conductivity, which are conflicting in existing fixation designs. In contrast, an electromagnetic position actuator in closed loop control provides stiffness without a path for thermal conduction. The radiative heat flow through such an actuator is analyzed. Furthermore, a thin thermal insulation is required to achieve a high magnetic field density at the location of the warm motor coils. Two insulation concepts are analyzed and compared based on the remaining heat flow. First order heat transfer equations are solved and the results show the potential of the solutions proposed. Further work entails detailed design and experimental verification. © 2018 CURRAN-CONFERENCE. All rights reserved.

关键词： Stiffness

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A Gaussian Process Regression for Natural Gas Consumption Prediction Based on Time Series Data

A Gaussian Process Regression for Natural Gas Consumption Pr...

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International Conference on Information Fusion

作者： Oussama Laib Mohamed Tarek Khadir Lyudmila Mihaylova Dep. of Computer Science University of Badji Mokhtar Annaba (UBMA) Annaba Algeria Dep. of Automatic Control and Systems Engineering (ACSE) University of Sheffield Sheffield UK

For several economical, financial and operational reasons, forecasting energy demand becomes a key instrument in energy system management. This paper develops a natural gas forecasting approach, which consists of two major phases: 1) it classifies the natural gas consumption daily pattern sequences into different groups with similar attributes. 2) the design and training of multiple autoregressive Gaussian Process models phase is carried out using the Algerian natural gas market data together with exogenous inputs consisting in weather (temperature) and calendar (day of the week, hour indicator) factors. The main novelty in this work consists of the investigation of multiple different clustering techniques for better analysis and clustering of natural gas consumption data. The impact of the obtained clusters, by each technique, is then summarized and evaluated with respect to the prediction accuracy.

关键词： Natural gas Forecasting Gaussian processes Load modeling Predictive models Clustering methods Kernel

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The performance potential of superconducting linear and planar motors 17

The performance potential of superconducting linear and plan...

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17th International Conference of the European Society for Precision engineering and Nanotechnology, EUSPEN 2017

作者： Koolmees, H.B. De Bruyn, B.J.H. Vermeulen, J.P.M.B. Jansen, J.W. Lomonova, E.A. Eindhoven University of Technology Dep. of Mechanical Engineering Control Systems Technology - Mechatronic Systems Design Netherlands Eindhoven University of Technology Dep. of Electrical Engineering Electromechanics and Power Electronics Netherlands

ISBN: (纸本)9780995775107

Electromagnetic motors currently used in lithography systems are pushed to their limit and it is challenging to increase acceleration without introducing additional disturbances. Superconductors could provide an improvement in magnetic flux density and/or current density compared to the permanent magnets and copper coils currently used. The improvement potential of three superconducting (SC) alternatives is analysed in this paper. The achievable magnetic flux density with SC electromagnets and SC bulk magnets is derived and the (alternating) current density in a SC coil is presented as a function of cooling power. All three are analysed for a range of cryogenic temperatures. An increase in magnetic flux density of a factor of three is computed at a temperature of 30 K and the same increase in current density is found at 50 K with equal cooling power compared to copper coils. As a result, superconductivity is expected to provide a significant improvement with respect to magnetic flux density and/or current density in a motor application.

关键词： Linear motors

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Towards autonomous reconfiguration in distribution networks: An approach based on finite state automaton models

Towards autonomous reconfiguration in distribution networks:...

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2017 Energy and Sustainability in Small Developing Economies, ES2DE 2017

作者： Košt'álová, Alena Carvalho, Pedro M. S. Kubalčík, Marek Dep. of Computer and Communication Systems Tomas Bata University in Zlin Czech Republic Electrical Engineering and Computer Dep. Instituto Superior Tecnico Lisbon Portugal Department of Process Control Tomas Bata University in Zlin Czech Republic

ISBN: (纸本)9781538620663

The demand on distribution network reconfiguration abilities is increasing. This paper proposes a Finite State Automaton model of a distribution network that deals with topologically safe reconfiguration. Autonomous operation of distribution networks can be designed, analysed and implemented in day-to-day operation with the aid of these automata: through supervisory control. Two approaches to supervisor design are proposed. One for the normal operating mode and the other for the contingency mode. Simple and comprehensive examples illustrate the approaches. © 2017 IEEE.

关键词： Topology

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Wavelet transform based technique for text image localization

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Karbala International Journal of Modern Science 2016年第2期2卷 138-144页

作者： Ali, Suhad A. Hashim, Ashwaq T. Babylon University Science College for Women Computer Science Dep. Babylon Iraq Technology University Control and Systems Engineering Dep. Baghdad Iraq

In this paper, a robust technique based on discrete wavelet transform, edge detection, and morphology operation for scene text detection is proposed. There are several stages in the proposed method. In the first stage, a single wavelet decomposition LH, HL and HH subbands are applied for detecting edges in original scene text image. The projection technique is applied in the second stage to preliminary detect text and non-text pixels. In third stage, 4-connected components are applied, and then area geometric feature is used as threshold to remove non-text region. At last stage, morphological operations are applied to connect isolated text components and to remove non-text regions. The proposed method is applied on a various images such as images of low contrast, complex background images and images of different fonts and size of text. The experimental results show that the proposed method can detect regions of the text perfectly. © 2016 The Authors

关键词： Connected components DWT Image projection Morphological operator

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