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4th International Conference on Future Generation Communication Technologies (FGCT)

作者： Prossegger, Markus Carinthia Univ Appl Sci Dept Engn & IT Klagenfurt Austria

ISBN: (纸本)9781479982677

The proceeding development of future communication networks depends on the continuous expansion of high bandwidth, fiber optic communication networks. While the costs for passive hardware components have fallen during the last years, the costs of building the cable route on the last mile (excavation and surface reconstruction work) is still the cost driver of network construction projects. A promising approach to minimize the investment costs is to use real-world spatial data together with mathematical optimization algorithms. This study examines the applicability of openly available spatial data in a cable route optimization approach. Based on OpenStreetMap data, a graph, as the fundamental structure of the applied operations research algorithm, is generated and weighted with real-world construction costs. Running an area-wide network construction experhnent, the quality and validity of the generated graph is compared to a graph based on commercial spatial data. The results show that the approach of using collaborative collected spatial data in the last mile cable route optimization is promising.

关键词： last mile Route optimization Networking spatial data optimization algorithms building costs Line graph

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Design optimization of IPM Machines for Efficient Operation in Extended Speed Range

Design Optimization of IPM Machines for Efficient Operation ...

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IEEE Transportation Electrification Conference and Exposition (ITEC)

作者： Fatemi, Alireza Demerdash, Nabeel A. O. Ionel, Dan M. Marquette Univ Dept Elect & Comp Engn Milwaukee WI 53233 USA

ISBN: (纸本)9781467367417

Practical considerations in the design of Interior Permanent Magnet (IPM) machines are examined to identify the key objectives for large-scale design optimization of such machines over an extended speed range. The goal of the optimization is to ensure efficient operation over the entire operating range under various performance and operational constraints. First, this paper illustrates that when the non-linear and lossy nature of the machine is considered from the efficiency standpoint, congruity of the characteristic versus the rated current cannot be the ideal criterion for constant power operation. Second, a new design optimization algorithm for constant power operation is developed which pursues efficient and reliable performance in the extended speed range under the rated current and maximum voltage constraints. To include the full non-linear nature of the machine and to address the effects of copper and iron losses on the motor behavior, this study is centered on finite element (FE) method for analysis and consequently optimization of a 50 hp, 48-slot, 8-pole IPM with single-layer v-type magnets which is used in the 2004 Toyota Prius. The results can be generalized to other PM motor configurations with sinusoidal back-emf waveforms.

关键词： speed range efficient functioning machine Optimal design current ratings constant power operation Integrated Pest Management machinery Core loss operating range Motor Activity power operation optimization algorithms

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Valve operation optimization for minimizing transient flow effects in Water Distribution Systems (WDS). Application to main pipes in Bogota, Colombia.

Valve operation optimization for minimizing transient flow e...

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World Environmental and Water Resources Congress

作者： Bohorquez, J. Saldarriaga, J. Univ Los Andes Water Distribut & Sewer Syst Res Ctr CIACUA Bogota Colombia

ISBN: (数字)9780784479162

ISBN: (纸本)9780784479162

Operational rules are key to accomplish a proper management of a Water Distribution Systems and transient flow events are also important to control because it can affect a system in a serious way. This paper proposes a methodology for obtaining the optimal valve closure curves in a real WDS in Bogota, Colombia in an emergency scenario. The paper first presents an overview about the main theoretical principles regarding transient flow that includes the valve hydraulic and the closure modelling. An optimization model is proposed that includes decision variables, restrictions, objective functions and optimization algorithms is proposed to address the problem. Given the nature of the problem, two approaches were used for its solution: monobjective and multiobjective. The results obtained show that a multiobjective approach allows for the obtaining of more closure curves than the monobjective approach.

关键词： primary pipe Water distribution systems Transient flow Wavelength dispersive spectroscopy Theoretical principles operation optimization VALVE GATE optimization algorithms surgical closure Emergencies

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Efficient Parallel optimization for Potts Energy with Hierarchical Fusion

Efficient Parallel Optimization for Potts Energy with Hierar...

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IEEE Conference on Computer Vision and Pattern Recognition (CVPR)

作者： Veksler, Olga Univ Western Ontario London ON Canada

ISBN: (纸本)9781467369640

Potts energy frequently occurs in computer vision applications. We present an efficient parallel method for optimizing Potts energy based on the extension of hierarchical fusion algorithm. Unlike previous parallel graph-cut based optimization algorithms, our approach has optimality bounds even after a single iteration over all labels, i.e. after solving only k-1 max-flow problems, where k is the number of labels. This is perhaps the minimum number of max-flow problems one has to solve to obtain a solution with optimality guarantees. Our approximation factor is O(log(2) k). Although this is not as good as the factor of 2 approximation of the well known expansion algorithm, we achieve very good results in practice. In particular, we found that the results of our algorithm after one iteration are always better than the results after one iteration of the expansion algorithm. We demonstrate experimentally the computational advantages of our parallel implementation on the problem of stereo correspondence, achieving a factor of 1.5 to 2.6 speedup compared to the serial implementation. These results were obtained with a small number of processors. The expected speedups with a larger number of processors are greater.

关键词： optimality Maximum Flow Parallel Lines iterative methods PROCESSOR Hierarchical optimization algorithms Fusion reactions Fusion, biological FUSION fusion (melting) Energy sources images computer vision

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Joint optimisation algorithm of cooperative spectrum sensing with cooperative overhead and sub-band transmission power for wideband cognitive radio network

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TRANSACTIONS ON EMERGING TELECOMMUNICATIONS TECHNOLOGIES 2015年第4期26卷 586-597页

作者： Liu, Xin Bi, Guoan Guan, Yong Liang Lu, Weidang Yan, Junhua Zhong, Weizhi Nanjing Univ Aeronaut & Astronaut Coll Astronaut Nanjing 210016 Jiangsu Peoples R China Nanyang Technol Univ Sch Elect & Elect Engn Singapore 637553 Singapore Zhejiang Univ Technol Zhejiang Prov Key Lab Commun Networks & Applicat Hangzhou 310023 Zhejiang Peoples R China

Cognitive radio (CR) allows a secondary user (SU) to utilise the spectrum allocated to the primary user (PU) on the premise of detecting the absence of PU by spectrum sensing. The SU often adopts cooperative spectrum sensing to cope with the hidden terminal problem if the PU is shadowed or in serious multi-path fading;however, the cooperative overhead may decrease the throughput of the SU. In this paper, we consider a wideband CR network that can reuse multiple idle sub-bands after cooperative spectrum sensing and then analyse the total throughput of the SU over all the sub-bands. A multi-variable nonconvex optimisation problem of cooperative spectrum sensing with cooperative overhead and sub-band transmission power is proposed, which maximises the total throughput of the SU subject to the constraints of the false-alarm probability, the detection probability, the cooperative overhead and the maximal total power of the SU. For obtaining the optimal solution, we divide the optimisation problem into two sub-optimisation problems: one for optimising the cooperative spectrum sensing including the sensing time and the number of SUs and the other one for optimising the sub-band transmission power. We have proven the convex optimisation of the two sub-optimisation problems and proposed a joint optimisation algorithm of the sensing time, the number of SUs and the sub-band transmission power. The simulation results show that the proposed joint optimisation algorithm can achieve the largest throughput with the false-alarm probability and the detection probability within their limits. Copyright (c) 2013 John Wiley & Sons, Ltd.

关键词： Spectra Sus Convex function power transmission Cognitive radio Throughput Plutonium optimization algorithms

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CMA-ES with Optimal Covariance Update and Storage Complexity 16

CMA-ES with Optimal Covariance Update and Storage Complexity

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Annual Conference on Neural Information Processing Systems

作者： Oswin Krause Didac R. Arbones Christian Igel Dept. of Computer Science University of Copenhagen Copenhagen Denmark

ISBN: (纸本)9781510838819

The covariance matrix adaptation evolution strategy (CMA-ES) is arguably one of the most powerful real-valued derivative-free optimization algorithms, finding many applications in machine learning. The CMA-ES is a Monte Carlo method, sampling from a sequence of multi-variate Gaussian distributions. Given the function values at the sampled points, updating and storing the covariance matrix dominates the time and space complexity in each iteration of the algorithm. We propose a numerically stable quadratic-time covariance matrix update scheme with minimal memory requirements based on maintaining triangular Cholesky factors. This requires a modification of the cumulative step-size adaption (CSA) mechanism in the CMA-ES, in which we replace the inverse of the square root of the covariance matrix by the inverse of the triangular Cholesky factor. Because the triangular Cholesky factor changes smoothly with the matrix square root, this modification does not change the behavior of the CMA-ES in terms of required objective function evaluations as verified empirically. Thus, the described algorithm can and should replace the standard CMA-ES if updating and storing the covariance matrix matters.

关键词： variance covariance matrix Covariance matrix Square root Cholesky Inverse Gaussian distribution space complexities Triangular memory requirements optimization algorithms

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Estimating Potential Revenue from Electrical Energy Storage in PJM

Estimating Potential Revenue from Electrical Energy Storage ...

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IEEE Power and Energy Society General Meeting

作者： Raymond H. Byrne Ricky J. Concepcion Cesar A. Silva-Monroy Sandia National Laboratories

ISBN: (纸本)9781509041695

FERC order 755 and FERC order 784 provide pay-for-performance requirements and direct utilities and independent system operators to consider speed and accuracy when purchasing frequency regulation. Independent System Operators (ISOs) have differing implementations of pay-for-performance. This paper focuses on the PJM implementation. PJM is a regional transmission organization in the northeastern United States that serves 13 states and the District of Columbia. PJM's implementation employs a two part payment based on the Regulation Market Capability Clearing price (RMCCP) and the Regulation Market Performance Clearing Price (RMPCP). The performance credit includes a mileage ratio. Both the RMCCP and RMPCP employ an actual performance score. Using the PJM remuneration model, this paper outlines the calculations required to estimate the maximum potential revenue from participation in arbitrage and regulation in day-ahead markets using linear programming. Historical PJM data from 2014 and 2015 was then used to evaluate the maximum potential revenue from a 5 MWh, 20 MW system based on the Beacon Power Hazle Township flywheel plant. Finally, a heuristic trading algorithm that does not require perfect foresight was evaluated against the results of the optimization algorithm.

关键词： Independent system operators Remuneration REVENUE optimization algorithms energy storage Frequency control Wages Northeastern United States Standing Orders Regulation (biology) electrical energy regional transmission

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Switched robust tracking/impedance control for an active transfemoral prosthesis

Switched robust tracking/impedance control for an active tra...

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American Control Conference

作者： Holly Warner Dan Simon Hadis Mohammadi Hanz Richter Cleveland State University OH United States

ISBN: (纸本)9781467386838

A novel control method for an active transfemoral prosthesis is developed based on the combination of two previously published controllers, robust tracking/impedance control and switched impedance control. This controller is simulated and optimized to provide desired gait features and energy regeneration. Specifically, an evolutionary optimization algorithm termed biogeography-based optimization is used. Across all optimization trials a tracking error on the order of 10-2 rad rms or less results for both the knee and ankle joints. This is accompanied by ground reaction forces approximating able-bodied gait data and an energy regeneration capacity of about 9.6 J per stride.

关键词： Impedance Robustness Switches Prosthetics Knee Hip Prosthesis Switches knee impedance Hip energy regeneration Robustness Ankle Joint optimization algorithms

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One optimized acoustic localization algorithm with temperature amendment

One optimized acoustic localization algorithm with temperatu...

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IEEE International Conference on Progress in Informatics and Computing (PIC)

作者： Linlin Cui Ping Song Key Laboratory of Biomimetic Robots and Systems Beijing institute of technology Beijing China

ISBN: (纸本)9781509034857

At present, the acoustic localization method is widely used. The high-precision acoustic localization algorithm is required urgently. The temperature is one major external factor which affects the localization precision greatly in the acoustic localization algorithm based on TDOA. It is found that the regional mean errors of the acoustic localization are smaller than others when the temperature changes around 25°C. And the regional mean errors of the acoustic localization change monotonically with temperature. One acoustic localization algorithm based on ten-element stereo array is presented. This algorithm has been optimized by temperature amendment. The experimental results show that the optimized algorithm has better localization precision than the original algorithm. The mean errors of X, Y, Z-coordinate using the optimized algorithm are separately 0.0758 m, 0.0586 m 0.0348 m smaller than the original algorithm.

关键词： array signal processing time-of-arrival estimation time-of-arrival estimation mean errors array signal processing optimization algorithms Acoustics Localization method

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A New Method for Quasi-Optimal Design of Water Distribution Networks

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WATER RESOURCES MANAGEMENT 2015年第14期29卷 5295-5308页

作者： Shirzad, Akbar Tabesh, Massoud Heidarzadeh, Moharram Urmia Univ Technol Fac Civil Engn Orumiyeh Iran Univ Tehran Ctr Excellence Engn & Management Civil Infrastruc Sch Civil Engn Coll Engn Tehran Iran West Azerbaijan Water & Wastewater Co Expert Urban Water Supply Orumiyeh West Azerbaijan Iran

In recent years optimal design of water distribution networks (WDNs) has been a subject of interest to several researchers. In this regard, in the previous researches various optimization techniques such as linear and non-linear programming and also meta-heuristic algorithms have been used for optimal design of WDNs. Among these techniques, meta-heuristic algorithms have shown the best performance. One of the disadvantages of implementing these methods for optimizing of WDNs is their high computational costs which make their usage sometimes impossible for large real life WDNs. In this paper a new method for quasi-optimal design of WDNs is presented. In the proposed method that is based on some hydraulic rules, diameters are selected so that the energy loss per unit length of pipes will be in a specific range. Using this method and without any requirement to available optimization techniques, design of WDNs can be done in a lower time relative to the mentioned techniques, so that the cost of the designed network will be very close to the least cost. Two sample networks have been designed using the proposed new method. Comparison of the obtained results with the available optimization techniques indicates the ability of this method to find the near optimal solutions in the shortest time.

关键词： Energy loss optimization algorithms Optimal design Water supply systems

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