The Experts below are selected from a list of 91665 Experts worldwide ranked by ideXlab platform
L Proslier - One of the best experts on this subject based on the ideXlab platform.
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Optimal Location of actuators and sensors in active vibration control
Journal of Intelligent Material Systems and Structures, 2005Co-Authors: I Bruant, L ProslierAbstract:Several studies have been conducted in order to find the Optimal Location of actuators and sensors in the active vibration control of structures. In this paper, a modified optimization criterion is proposed for these two optimization problems, ensuring good observability or good controllability of the structure, and considering residual modes to limit the spill-over effects. Its efficiency is shown by the comparison with the classical criteria, illustrated for a simply supported beam and a rectangular plate. In these two applications, the number of active elements is discussed, using or neglecting the residual modes.
Cheng Jiu-long - One of the best experts on this subject based on the ideXlab platform.
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Optimal Location Queries in Road Networks
ACM Transactions on Database Systems, 2015Co-Authors: Zitong Chen, Jiamin Xiong, Ganglin Mai, Yubao Liu, Raymond Chi-wing Wong, Cheng Jiu-longAbstract:In this article, we study an Optimal Location query based on a road network. Specifically, given a road network containing clients and servers, an Optimal Location query finds a Location on the road network such that when a new server is set up at this Location, a certain cost function computed based on the clients and servers (including the new server) is optimized. Two types of cost functions, namely, MinMax and MaxSum, have been used for this query. The Optimal Location query problem with MinMax as the cost function is called the MinMax query, which finds a Location for setting up a new server such that the maximum cost of a client being served by his/her closest server is minimized. The Optimal Location query problem with MaxSum as the cost function is called the MaxSum query, which finds a Location for setting up a new server such that the sum of the weights of clients attracted by the new server is maximized. The MinMax query and the MaxSum query correspond to two types of Optimal Location query with the objectives defined from the clients' perspective and from the new server's perspective, respectively. Unfortunately, the existing solutions for the Optimal query problem are not efficient. In this article, we propose an efficient algorithm, namely, MinMax-Alg (MaxSum-Alg), for the MinMax (MaxSum) query, which is based on a novel idea of nearest Location component. We also discuss two extensions of the Optimal Location query, namely, the Optimal multiple-Location query and the Optimal Location query on a 3D road network. Extensive experiments were conducted, showing that our algorithms are faster than the state of the art by at least an order of magnitude on large real benchmark datasets. For example, in our largest real datasets, the state of the art ran for more than 10 (12) hours while our algorithm ran within 3 (2) minutes only for the MinMax (MaxSum) query, that is, our algorithm ran at least 200 (600) times faster than the state of the art.
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SIGMOD Conference - Efficient algorithms for Optimal Location queries in road networks
Proceedings of the 2014 ACM SIGMOD International Conference on Management of Data, 2014Co-Authors: Zitong Chen, Jiamin Xiong, Ganglin Mai, Yubao Liu, Raymond Chi-wing Wong, Cheng Jiu-longAbstract:In this paper, we study the Optimal Location query problem based on road networks. Specifically, we have a road network on which some clients and servers are located. Each client finds the server that is closest to her for service and her cost of getting served is equal to the (network) distance between the client and the server serving her multiplied by her weight or importance. The Optimal Location query problem is to find a Location for setting up a new server such that the maximum cost of clients being served by the servers (including the new server) is minimized. This problem has been studied before, but the state-of-the-art is still not efficient enough. In this paper, we propose an efficient algorithm for the Optimal Location query problem, which is based on a novel idea of \emph{nearest Location component}. We also discuss three extensions of the Optimal Location query problem, namely the Optimal multiple-Location query problem, the Optimal Location query problem on 3D road networks, and the Optimal Location query problem with another objective. Extensive experiments were conducted which showed that our algorithms are faster than the state-of-the-art by at least an order of magnitude on large real benchmark datasets. For example, on our largest real datasets, the state-of-the-art ran for more than 10 hours but our algorithm ran within 3 minutes only (i.e., >200 times faster).
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Efficient algorithms for Optimal Location queries in road networks
2014Co-Authors: Zitong Chen, Jiamin Xiong, Yubao Liu, Raymond Chi-wing Wong, Cheng Jiu-long, Ganglin MaiAbstract:In this paper, we study the Optimal Location query problem based on road networks. Specifically, we have a road network on which some clients and servers are located. Each client finds the server that is closest to her for service and her cost of getting served is equal to the (network) distance between the client and the server serving her multiplied by her weight or importance. The Optimal Location query problem is to find a Location for setting up a new server such that the maximum cost of clients being served by the servers (including the new server) is minimized. This problem has been studied before, but the state-of-the-art is still not efficient enough. In this paper, we propose an efficient algorithm for the Optimal Location query problem, which is based on a novel idea of \emph{nearest Location component}. We also discuss three extensions of the Optimal Location query problem, namely the Optimal multiple-Location query problem, the Optimal Location query problem on 3D road networks, and the Optimal Location query problem with another objective. Extensive experiments were conducted which showed that our algorithms are faster than the state-of-the-art by at least an order of magnitude on large real benchmark datasets. For example, on our largest real datasets, the state-of-the-art ran for more than 10 hours but our algorithm ran within 3 minutes only (i.e., >200 times faster).
S.a. Nabavi Niaki - One of the best experts on this subject based on the ideXlab platform.
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multiobjective Optimal Location of facts shunt series controllers for power system operation planning
IEEE Transactions on Power Delivery, 2012Co-Authors: Ahad Kazemi, S.a. Nabavi NiakiAbstract:This paper develops appropriate models of flexible ac transmission systems (FACTS) shunt-series controllers for multiobjective optimization and also presents a multiobjective optimization methodology to find the Optimal Location of FACTS shunt-series controllers. The objective functions are the total fuel cost, power losses, and system loadability with and without minimum cost of FACTS installation. The e-constraint approach is implemented for the multiobjective mathematical programming (MMP) formulation, including the FACTS shunt-series controllers (i.e., phase-shifting transformer (PST), hybrid flow controller (HFC), and unified power-flow controller (UPFC)). Simulation results are presented for the IEEE 14-bus system. The optimization method is numerically solved using Matlab and general algebraic modeling system (GAMS) software environments. The solution procedure uses nonlinear programming (NLP) and mixed-integer nonlinear programming (MINLP) to solve the Optimal Location and setting of FACTS incorporated in the Optimal power-flow problem considering these objective functions and improving the power system operation. Furthermore, the results demonstrate that the HFC is outperformed by PST and UPFC from the analytical and technical point of views.
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Optimal Location of Hybrid Flow Controller considering modified steady-state model
Applied Energy, 2011Co-Authors: A. Lashkar Ara, Ahad Kazemi, S.a. Nabavi NiakiAbstract:This paper introduces a modified power flow model for Hybrid Flow Controller (HFC) as an energy flow controller. The existing power flow models for Hybrid Flow Controller are suitable only for conventional power flow analysis, and are not applicable for OPF and Optimal Location analysis of FACTS devices. In this paper, some modifications were applied to the existing models to promote the accuracy and improve their conformability on any power system and hence leading to a precise steady-state analysis. The modified model and the existing model are investigated using different IEEE test systems and the results are compared together. The optimization method is numerically solved using Matlab and General Algebraic Modelling System (GAMS) software environments. The solution procedure uses Mixed Integer Non-Linear Programming (MINLP) and Relaxed Mixed Integer Non-Linear Programming (RMINLP) to solve the Optimal Location and setting of HFC incorporated in OPF problem considering the total fuel cost, power losses, and the system loadability as objective functions for single objective optimization problem and improve the power system operation.
Fred F Choobineh - One of the best experts on this subject based on the ideXlab platform.
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Optimal Location alLocation of tcsc devices on a transmission network
IEEE Transactions on Power Systems, 2017Co-Authors: Omid Ziaee, Fred F ChoobinehAbstract:Installing a thyristor controlled series capacitor (TCSC) device on a transmission network reduces network congestion and generation cost. We formulate the TCSC Location-alLocation problem as a mixed integer nonlinear program, and propose a novel decomposition procedure for determining the Optimal Location of TCSCs and their respective size for a network. The load uncertainty, AC characteristic of transmission lines, and nonlinear cost of TCSCs explicitly are considered. The results of applying the procedure to the IEEE 118-bus test system are reported, and insights into the TCSC Location-alLocation problem are provided.
I Bruant - One of the best experts on this subject based on the ideXlab platform.
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Optimal Location of actuators and sensors in active vibration control
Journal of Intelligent Material Systems and Structures, 2005Co-Authors: I Bruant, L ProslierAbstract:Several studies have been conducted in order to find the Optimal Location of actuators and sensors in the active vibration control of structures. In this paper, a modified optimization criterion is proposed for these two optimization problems, ensuring good observability or good controllability of the structure, and considering residual modes to limit the spill-over effects. Its efficiency is shown by the comparison with the classical criteria, illustrated for a simply supported beam and a rectangular plate. In these two applications, the number of active elements is discussed, using or neglecting the residual modes.
