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Self-Injection-Locked Kerr Soliton Microcombs With Photonic Wire Bonds For Use in Terahertz Communications

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Self-Injection-Locked Kerr Soliton Microcombs With Photonic ...

Conference on Lasers and Electro-Optics (CLEO)

作者： Y. Chen H. Peng D. Fang J. Dittmer G. Lihachev A. Voloshin S. T. Skacel M. Lauermann A. Tessmann S. Wagner S. Bhave I. Kallfass T. Zwick W. Freude S. Randel T. J. Kippenberg C. Koos Inst. of Photon. & Quant. Electron.(IPQ) Inst. of Microstruct. Technol. (IMT) Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne Switzerland Deeplight S.A. Lausanne Switzerland Vanguard Automation GmbH Karlsruhe Germany Fraunhofer Institute for Applied Solid State Physics (IAF) Freiburg Germany OxideMEMS Lab Purdue University USA Inst. of Robust Power Semiconductor Systems University of Stuttgart Germany Inst. of Radio Frequency Engineering and Electronics (IHE) Karlsruhe Institute of Technology (KIT) Germany

We demonstrate single-soliton Kerr-comb generators, exploiting photonic wire bonds to connect Si 3 N 4 resonators and self-injection-locked InP pump lasers. The assembly is used to generate a 0.302 THz carrier for 16... 详细信息

ISBN: (纸本)9781957171258

关键词： Distributed feedback lasers Frequency combs Injection locking Laser resonators Phase noise Ring resonators

Initial analysis of the impact of the Ukrainian power grid synchronization with Continental Europe

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arXiv 2022年

作者： Böttcher, Philipp C. Gorjão, Leonardo Rydin Beck, Christian Jumar, Richard Maass, Heiko Hagenmeyer, Veit Witthaut, Dirk Schäfer, Benjamin Jülich52428 Germany Department of Computer Science OsloMet – Oslo Metropolitan University OsloN-0130 Norway Queen Mary University of London School of Mathematical Sciences Mile End Road LondonE1 4NS United Kingdom The Alan Turing Institute 96 Euston Road LondonNW1 2DB United Kingdom Institute for Automation and Applied Informatics Karlsruhe Institute of Technology Eggenstein-Leopoldshafen76344 Germany Institute for Theoretical Physics University of Cologne Köln50937 Germany

When Russia invaded Ukraine on the 24th of February 2022, this led to many acts of solidarity with Ukraine, including support for its electricity system. Just 20 days after the invasion started, the Ukrainian and Moldovan power grids were synchronized to the Continental European power grid to provide stability to these grids. Here, we present an initial analysis of how this synchronization affected the statistics of the power grid frequency and cross-border flows of electric power within Continental Europe. We observe faster inter-area oscillations, an increase in fluctuations and changes in the cross-border flows in and out of Ukraine and surrounding countries as an effect of the synchronization with Continental Europe. Overall these changes are small such that the now connected system can be considered as stable as before the synchronization. Copyright © 2022, The Authors. All rights reserved.

关键词： Synchronization

Heuristics for Transmission Expansion Planning in Low-Carbon Energy System Models

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Heuristics for Transmission Expansion Planning in Low-Carbon...

International Conference on European Electricity Market, EEM

作者： Fabian Neumann Tom Brown Institute for Automation and Applied Informatics Karlsruhe Institute of Technology

Governments across the world are planning to increase the share of renewables in their energy systems. The siting of new wind and solar power plants requires close coordination with grid planning, and hence co-optimization of investment in generation and transmission expansion in spatially and temporally resolved models is an indispensable but complex problem. Particularly considerations of transmission expansion planning (TEP) add to the problem's complexity. Even if the power flow equations are linearized, the optimization problem is still bilinear and mixed-integer due to the dependence of line expansion on line impedance and a discrete set of line expansion options. While it is possible to linearize this mixed-integer nonlinear program (MINLP) by applying a big-M disjunctive relaxation, the resulting MILP is still hard to solve using state-of-the-art solvers for large-scale energy system models. In this paper we therefore develop heuristics to incorporate integer transmission expansion and responsive line impedances in energy system models, while retaining the lower computational effort of continuous linear programming (LP) by applying sequential linear programming (SLP) techniques, relaxation and discretization approaches. We benchmark their performance against the results of the exact formulation for a policy-relevant case study of the German transmission system in terms of their speed-up in computation time, deviation from optimal total system cost, and similarity of line expansion. Using heuristics we reduce computation times of joint generation and transmission optimisation by 82% with a maximal total system cost deviation of only 1.5%. The heuristics closely mirror optimal integer line investment of the exact MINLP with considerable time savings for policy-relevant low-carbon energy system optimization models.

关键词： Investment Optimization Planning Mathematical model Linear programming Computational modeling Generators

Heuristics for Transmission Expansion Planning in Low-Carbon Energy System Models

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arXiv 2019年

作者： Neumann, Fabian Brown, Tom Institute for Automation and Applied Informatics Karlsruhe Institute of Technology

Governments across the world are planning to increase the share of renewables in their energy systems. The siting of new wind and solar power plants requires close coordination with grid planning, and hence co-optimization of investment in generation and transmission expansion in spatially and temporally resolved models is an indispensable but complex problem. Particularly considerations of transmission expansion planning (TEP) add to the problem’s complexity. Even if the power flow equations are linearized, the optimization problem is still bilinear and mixed-integer due to the dependence of line expansion on line impedance and a discrete set of line expansion options. While it is possible to linearize this mixed-integer nonlinear program (MINLP) by applying a big-M disjunctive relaxation, the resulting MILP is still hard to solve using state-of-the-art solvers for large-scale energy system models. In this paper we therefore develop heuristics to incorporate integer transmission expansion and responsive line impedances in energy system models, while retaining the lower computational effort of continuous linear programming (LP) by applying sequential linear programming (SLP) techniques, relaxation and discretization approaches. We benchmark their performance against the results of the exact formulation for a policy-relevant case study of the German transmission system in terms of their speed-up in computation time, deviation from optimal total system cost, and similarity of line expansion. Using heuristics we reduce computation times of joint generation and transmission optimisation by 82% with a maximal total system cost deviation of only 1.5%. The heuristics closely mirror optimal integer line investment of the exact MINLP with considerable time savings for policy-relevant low-carbon energy system optimization models. Copyright © 2019, The Authors. All rights reserved.

关键词： Expansion

On the SCD semismooth* Newton method for generalized equations with application to a class of static contact problems with Coulomb friction

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arXiv 2022年

作者： Gfrerer, Helmut Mandlmayr, Michael Outrata, Jiří V. Valdman, Jan Institute of Computational Mathematics Johannes Kepler University Linz LinzA-4040 Austria Institute of Information Theory and Automation Czech Academy of Sciences Prague18208 Czech Republic Centre for Informatics and Applied Optimization Federation University of Australia POB 663 BallaratVIC3350 Australia Department of Applied Mathematics Faculty of Information Technology Czech Technical University in Prague Thákurova 9 Prague16000 Czech Republic

In the paper, a variant of the semismooth∗ Newton method is developed for the numerical solution of generalized equations, in which the multi-valued part is a so-called SCD (subspace containing derivative) mapping. Under a rather mild regularity requirement, the method exhibits (locally) superlinear convergence behavior. From the main conceptual algorithm, two implementable variants are derived whose efficiency is tested via a generalized equation modeling a discretized static contact problem with Coulomb *** Codes 65K10, 65K15, 90C33 © 2022, CC BY.

关键词： Newton-Raphson method

Tool for Diagnosis of Stochastic Automata

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Tool for Diagnosis of Stochastic Automata

International Conference on Event-based Control, Communication, and Signal Processing (EBCCSP)

作者： Štefan Krištofik Jana Flochová Institute of Informatics Slovak Academy of Sciences Bratislava Slovakia Institute of Applied Informatics Automation and Mechatronics Slovak University of Technology Trnava Slovakia

The following topics are dealt with: medical signal processing; field programmable gate arrays; time-digital conversion; electrocardiography; medical signal detection; signal sampling; signal processing; digital signa... 详细信息

ISBN: (数字)9781728195810

ISBN: (纸本)9781728195827

关键词： Automata Stochastic processes Tools Converters Finite element analysis Operating systems informatics

Introduction to MATLAB

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Advanced Textbooks in Control and Signal Processing

Advanced Textbooks in Control and Signal Processing 2019年 1-27页

作者： Keviczky, László Bars, Ruth Hetthéssy, Jenő Bányász, Csilla Institute for Computer Science and Control Hungarian Academy of Sciences Budapest Hungary Department of Automation and Applied Informatics Budapest University of Technology and Economics Budapest Hungary

MATLAB™ is an interactive environment for scientific and engineering calculations, simulations, and data visualization. MATLAB™ provides a powerful platform to solve mathematical and engineering problems related to matrix algebra, differential equations, etc. MATLAB is especially effective in solving control problems. SIMULINK provides block-oriented simulation. The chapter gives a short introduction to MATLAB and SIMULINK. © Springer Nature Singapore Pte Ltd. 2019.

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A New Communication Concept for Efficient Configuration of Energy Systems Integration Co-Simulation

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A New Communication Concept for Efficient Configuration of E...

International Workshop/Symposium on Distributed Simulation and Real-Time Applications (DS-RT)

作者： Anselm Erdmann Hüseyin K. Çakmak Uwe Kühnapfel Veit Hagenmeyer Institute for Automation and Applied Informatics Karlsruhe Institute of Technology Karlsruhe Germany

By combining several existing simulators, co-simulation approaches are designed for efficient simulator development. Especially for energy systems integration simulations involving different physical domains, co-simulation is the required approach. However, co-simulation setup is complex, time-consuming, and additionally, error-prone for large simulations, especially if visualizations are included. Therefore, for an intensive information exchange between simulators, the present paper introduces a new network-based communication concept including the co-simulation setup procedure. The proposed setup concept enables an efficient configuration for the coupling of distributed simulation modules. The evaluation of the implemented concept on an exemplary power grid simulation with integration of power-to-gas and gas-to-power components and power grid visualization shows the ability for efficient handling of a high amount of exchanged simulation data.

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A comparison of partitioning strategies in AC optimal power flow

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arXiv 2019年

作者： Murray, Alexander Kyesswa, Michael Schmurr, Philipp Çakmak, Hüseyin K. Hagenmeyer, Veit Institute for Automation and Applied Informatics Karlsruhe Institute of Technology Karlsruhe Germany

—The highly non-convex AC optimal power flow problem is known to scale very poorly with respect to the number of lines and buses. To achieve improved computational speed and scalability, we apply a distributed optimization algorithm, the so-called Augmented Lagrangian based Alternating Direction Inexact Newton (ALADIN) method. However, the question of how to optimally partition a power grid for use in distributed optimization remains open in the literature. In the present paper, we compare four partitioning strategies using the standard IEEE 9, 14, 30, 39, 57, 118, 300 bus models as the performance benchmark. To this end, we apply the graph partitioners KaFFPa and METIS as well as two spectral clustering methods to the aforementioned bus models. For larger grids, KaFFPa yields the best results on average. Copyright © 2019, The Authors. All rights reserved.

关键词： Acoustic generators