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Intelligent management of coal stockpiles using improved grey spontaneous combustion forecasting models

ENERGY 2017年 132卷 269-279页

作者： Peng, Gongzhuang Wang, Hongwei Song, Xiao Zhang, Heming Tsinghua Univ Dept Automat Beijing 100084 Peoples R China Huadian Elect Power Res Inst Hangzhou 310030 Zhejiang Peoples R China Univ Portsmouth Sch Engn Portsmouth P01 3DJ Hants England Beihang Univ BUAA Sch Automat Sci Beijing 100191 Peoples R China

Intelligent coal stockpiles management system is significant for the next-generation cleaner power plants. Prevention of spontaneous combustion is a key issue for such a system, both in economic and environmental terms. As many factors can influence the self heating process of coal such as moisture and ash in coal, temperature distribution and stockpiles' shapes, the remaining ignition time is developed as an aggregative indicator to measure the tendencies of spontaneous coal combustion. Using this value, the grey models have been applied to forecast spontaneous combustion and their performances are good for systems with insufficient information. However, the forecasting accuracy of these models still needs to be improved. Therefore, the ABC-RGM(1,1) model is proposed in this work based on the rolling-GM(1,1) and the Artificial Bee Colony (ABC) optimization algorithm, which has been applied to the management system of a 4 x 600 MW power plant. The computational experiments show that the ABC-RGM(1,1) model achieves better performance than the other popular grey models and accuracy of forecast is greatly improved especially for short-term forecasts. Such an accurate model is highly important and useful for intelligent coal management systems which can improve decision making and reduce risk. (C) 2017 Elsevier Ltd. All rights reserved.

关键词： Coal management Spontaneous combustion prevention Grey model optimization algorithm

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A design optimization technique for multi-robot systems 55

A design optimization technique for multi-robot systems

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55th AIAA Aerospace Sciences Meeting

作者： Durand, Jean-Guillaume Burgaud, Frédéric Cooksey, K.D. Mavris, Dimitri N. Georgia Institute of Technology AtlantaGA30332-0150 United States School of Aerospace Engineering 270 Ferst Dr Mail Stop 0150 United States Aerospace Systems Design Laboratory 275 Ferst Drive #3 AtlantaGA30332 United States Aerospace Systems Design Laboratory School of Aerospace Engineering 270 Ferst Dr Mail Stop 0150 United States

ISBN: (数字)9781624104473

ISBN: (纸本)9781624104473

Despite being more flexible, robust, and scalable than single robot solutions, multi-robot systems suffer from a lack of democratization. Most applications are found in academia or rare avant-gardist military projects with very few, if none, commercial implementations. This is due in part to the complex system of systems design process requiring the optimization of not only the group architecture, but also the individual agents, for the group operation. Such an intricate procedure, as well as the lack of link between the microscopic level and the macroscopic level of the system, leads to suboptimal designs. Focused on micro unmanned aerial vehicles, this paper proposes a novel bi-lebel optimization technique which differs from the classical sequential approach presently utilized by the community. The results of this global optimization scheme applied to a simple example show that performance improvements up to thirty percent can be achieved on designs. Moreover, the optimization step is shown to be not more computationally expensive than the current paradigm. © 2017 by Jean-Guillaume Durand, Frédéric Burgaud, K. D. Cooksey, Dimitri N. Mavris.

关键词： Multi Robot Systems Aerial Robots Unmanned Aerial Vehicle Swarm Robotics optimization algorithm Supply Chain Management Genetic algorithm Space Exploration Aerodynamics Metaheuristic Approach

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Droplet Size-Aware High-Level Synthesis for Micro-Electrode-Dot-Array Digital Microfluidic Biochips

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IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2017年第3期11卷 612-626页

作者： Li, Zipeng Lai, Kelvin Yi-Tse Yu, Po-Hsien Chakrabarty, Krishnendu Ho, Tsung-Yi Lee, Chen-Yi Duke Univ Dept Elect & Comp Engn Durham NC 27708 USA Natl Chiao Tung Univ Dept Elect Engn Hsinchu 300 Taiwan Natl Tsing Hua Univ Dept Comp Sci Hsinchu 30013 Taiwan

A digital microfluidic biochip (DMFB) is an attractive technology platform for automating laboratory procedures in biochemistry. In recent years, DMFBs based on a microelectrodedot- array (MEDA) architecture have been demonstrated. However, due to the inherent differences between today's DMFBs and MEDA, existing synthesis solutions for biochemistry mapping cannot be utilized for MEDA biochips. We present the first synthesis approach that can be used for MEDA biochips. We first present a general analytical model for droplet velocity and validate it experimentally using a fabricated MEDA biochip. We then present the proposed synthesis method targeting reservoir placement, operation scheduling, module placement, routing of droplets of various sizes, and diagonal movement of droplets in a two-dimensional array. Simulation results using benchmarks and experimental results using a fabricated MEDA biochip demonstrate the effectiveness of the proposed synthesis technique.

关键词： Digital microfluidics high-level synthesis lab-on-chip micro-electrode-dot-array (MEDA) optimization algorithm

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Enhanced Second Harmonic Generation Efficiency via Wavefront Sha

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ACS PHOTONICS 2017年第7期4卷 1790-1796页

作者： Thompson, Jonathan V. Hokr, Brett H. Throckmorton, Graham A. Wang, Dawei Scully, Marlan O. Yakovlev, Vladislav V. Texas A&M Univ College Stn TX 77843 USA Baylor Univ Waco TX 76798 USA

Optical second harmonic generation is a fundamental nonlinear effect with a large impact on laser technology and optical imaging/sensing. For most practical applications of second harmonic generation, high conversion efficiency is required. However, many techniques used to achieve high efficiency are limited to fabrication methods and optical energy requirements. Here, we investigate and demonstrate substantial enhancement in the conversion efficiency of second harmonic generation in a nonlinear crystal via the application of wavefront shaping. In a one dimensional understanding of second harmonic generation, a phase offset applied to the fundamental wave has no effect on the intensity of the generated light. We show that when the pump field is not a plane wave, enhanced conversion efficiency can be controlled by the application of a phase mask to the fundamental beam. This investigation of the dependence of conversion efficiency upon the transverse phase profile of the incident pump laser yields the promise of new ways to enhance nonlinear generation with limited optical energy and without the need for specific fabrication techniques.

关键词： wavefront shaping second harmonic generation optimization algorithm nonlinear crystal conversion efficiency nonlinear generation

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PI controller design via ABC algorithm for MPPT of PV system supplying DC motor-pump load

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ELECTRICAL ENGINEERING 2017年第2期99卷 505-518页

作者： Oshaba, A. S. Ali, E. S. Abd Elazim, S. M. Power Elect & Energy Convers Elect Res Inst NRC Blg Giza 12311 Egypt Zagazig Univ Elect Power & Machine Dept Fac Engn Zagazig Egypt

Artificial Bee Colony (ABC) algorithm has various features that make it more attractive than other algorithms. Particularly, it is simple, it uses fewer control parameters and its convergence is independent of the initial conditions. In this paper, a new MPPT system has been suggested for photovoltaic (PV)-DC motor-pump system by designing two PI controllers via ABC algorithm. The first one is used to reach MPPT by monitoring the voltage and current of the PV array and adjusting the duty cycle of the DC/DC converter. The second PI controller is designed for speed control of DC series motor by setting the voltage fed to the DC series motor through another DC/DC converter. The suggested design problem of MPPT and speed controller is formulated as an optimization task which is solved by ABC to search for optimal parameters of PI controllers. Simulation results have shown the validity of the developed technique in delivering MPPT to DC series motor-pump system under atmospheric conditions and tracking the reference speed of motor. Moreover, the performance of the ABC algorithm is compared with Genetic algorithm (GA) for various disturbances to prove its robustness.

关键词： Artificial bee colony DC series motor-pump system Photovoltaic system optimization algorithm Maximum power point tracking PI controller

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The stochastic lot-sizing problem with lost sales: A chemical-Petrochemical case study

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JOURNAL OF MANUFACTURING SYSTEMS 2017年第Part1期44卷 53-64页

作者： Ghamari, Ali Sahebi, Hadi Iran Univ Sci & Technol Sch Ind Engn Tehran *** Iran

The recent evidence shows that production planning problems (e.g. lot sizing) in the manufacturing systems in general, and in the petrochemical sector in particular, can be very challenging. This fact, that the flows of chemical materials usually are continuous and the demands of chemical-petrochemical products inherently are uncertain, motivating researchers and practitioners to deal with stochastic lot sizing models in this manufacturing systems. This paper formulates such problems by taking distribution functions (discreet and continuous) into account. Moreover, lost sales are considered under the "static uncertainty" strategy. A solution methodology, additionally, is presented to determine the optimal timing and level of orders, when demand is defined by a discrete distribution function. To show the efficiency and effectiveness of proposed models and solution algorithm, a chemical-petrochemical case study as well as two other numerical example are described and solved. (C) 2017 The Society of Manufacturing Engineers. Published by Elsevier Ltd. All rights reserved.

关键词： Inventory planning Stochastic lot-sizing Multi-period models Lost sales optimization algorithm

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A generalized design of distributed rateless codes with decreasing ripple size for multiple-access relay networks

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WIRELESS NETWORKS 2017年第7期23卷 2177-2188页

作者： Liao, Jianxin Zhang, Lei Li, Tonghong Wang, Jingyu Qi, Qi Beijing Univ Posts & Telecommun State Key Lab Network & Switching Technol Beijing 100876 Peoples R China EBUPT Informat Technol Co Ltd Beijing 100191 Peoples R China Tech Univ Madrid Dept Comp Sci Madrid Spain

In this correspondence, the problem of existing distributed rateless codes (DRC) with inaccurate degree distributions in the sources and the relay is addressed. Based on a well-known multiple-access relay network model, a generalized design of DRC (GDRC) is proposed by using optimization theory and heuristic Jacobian iterative algorithm, in which the interaction between the degree distributions in the sources and in the relay is considered. Our GDRC can be applied to Luby transfer codes or any other rateless codes that can be described with a degree distribution. Furthermore, a novel approach of designing GDRC with decreasing ripple size is proposed by directly analysing the interaction between the ripple size revolutions in the sources and in the relay. Our proposed scheme is evaluated and compared with existing schemes. It is shown that our proposed scheme exhibits reduced overhead, memory usage, bit error rate and energy consumption compared to the existing schemes.

关键词： Distributed rateless codes Degree distribution Heuristic matrixes optimization algorithm

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Kalman-Filter-Based Unconstrained and Constrained Extremum-Seeking Guidance on SO(3)

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2017年第9期40卷 2260-2271页

作者： Walsh, Alex Forbes, James Richard Chee, Stephen Alexander Ryan, John Jens Univ Michigan Dept Aerosp Engn Francois Xavier Bagnound Bldg1320 Beal Ave Ann Arbor MI 48109 USA McGill Univ Dept Mech Engn Macdonald Engn Bldg817 Sherbrooke St West Montreal PQ H3A 0C3 Canada NASA Langley Res Ctr Dynam Syst & Controls Hampton VA 23681 USA

Extremum-seeking guidance endeavors to drive the output of a system to the extremum of an unknown objective function. This paper proposes an extremum-seeking guidance algorithm on SO(3) for cases with and without inclusion and exclusion zones. The gradient of the unknown objective function is estimated via a Kalman filter so that the extremum of the objective function can be approximated. To satisfy inclusion and exclusion zone constraints, two different constrained Kalman filters are proposed. The first Kalman filter is a gain-projected Kalman filter, and the second is a novel linear matrix inequality based Kalman filter that is able to accommodate a larger class of constraints. The proposed extremum-seeking guidance algorithm is demonstrated using a performance objective that relates a spacecraft's attitude to received power of an unknown radiation source using a patch antenna.

关键词： Kalman Filter Guidance algorithms Radiation Pattern Spacecraft Attitude Taylor Series Attitude Control optimization algorithm Spacecraft Dynamics Guidance Laws Feedback Control

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Study on the evaluation of cylinder's global sizes

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PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY 2017年 49卷 189-199页

作者： Zhao, Zexiang Li, Bin Zhang, Guoqing Yu, Hechun Wang, Wenbo He, Xin Hou, Xiaoshuai Cheng, Xupeng Yao, Bo Zhongyuan Univ Technol Sch Mechatron Engn Zhengzhou 450007 Peoples R China

In ISO 14405-1, the global sizes, such as least-squares diameter, minimum circumscribed diameter and maximum inscribed diameter are defined. The diameters above can be measured by using cylindrical coordinate measuring method like the circular section measuring method of cylindricity error. The determination method of the least-squares diameter was firstly given based on the cylindrical measuring system, and the optimization models of the minimum circumscribed diameter and the maximum inscribed diameter were built, respectively. The corresponding objective functions were unified as "minimax" expressions. For the four axis parameters of the cylinder with the minimum circumscribed diameter or the maximum inscribed diameter, the searching ranges of cylinder's axis parameters for their optimal solutions were defined numerically. Thereafter, the genetic, steepest decent and BFGS-0.618 algorithms were introduced, and the optimization evaluation algorithms of two kinds of diameters mentioned above were given. Based on many cylinders' profiles obtained by the circular section measuring method on a measuring instrument of cylinder's global sizes which was developed by Zhongyuan University of Technology, Zhengzhou, China. The accuracy, efficiency and suitability of three optimization algorithms were investigated through the evaluation of a lot of the minimum circumscribed diameters and the maximum inscribed diameters. The measurement uncertainty of the global sizes for the cylindrical specimen was analyzed, and the measurement uncertainties of the sizes in the radial and z directions are +/- 0.95 mu m and +/- 0.5 mu m, respectively. The total measurement uncertainties of the global sizes of the cylindrical specimens with the specifications of phi 10 x 120 mm and phi 100 x 300 mm are +/- 3.8 mu m and +/- 5.7 mu m, respectively. The investigation results showed that for the evaluation of the globe sizes, any one of three algorithms above is not absolutely prior to the other two

关键词： Global sizes optimization algorithm Genetic algorithm Steepest descent algorithm Maximum inscribed diameter Minimum circumscribed diameter Least-squares diameter

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An Optimal Design Strategy for a Thomson Coil Actuator

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JOURNAL OF ELECTRICAL ENGINEERING & TECHNOLOGY 2017年第1期12卷 182-188页

作者： Lim, Dong-Kuk Jung, Sang-Yong Jung, Hyun-Kyo Ro, Jong-Suk Chung Ang Univ Sch Elect & Elect Engn Seoul South Korea Seoul Natl Univ Dept Elect & Comp Engn Seoul 151 South Korea Sungkyunkwan Univ Sch Elect & Elect Engn Seoul South Korea

An arc eliminator allows a surge current bypass rapidly into the earth to facilitate the circuit breaking process and increase the stability of the load circuit. Thomson coil actuator (TCA) is a type of actuator that can function as an arc eliminator. The TCA has a simple structure and significantly rapid speed compared to the other types of actuators. In this paper, significant variables, which have a dominant effect on the performance of the TCA, are investigated in detail. Using these variables and an optimization algorithm, an optimal design strategy for the TCA is proposed in this research. The efficacy of the proposed optimal design strategy and the feasibility of the application of the designed TCA for a high power circuit breaker as the arc eliminators are validated through the experiment.

关键词： Actuator Circuit breaker optimization algorithm Thomson coil actuator

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