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Applying micro genetic algorithm to numerical model for luminous intensity distribution of planar prism LED luminaire

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OPTICS COMMUNICATIONS 2013年 293卷 22-30页

作者： Kim, Yu-Sin Choi, An-Seop Jeong, Jae-Weon Sejong Univ Dept Architectural Engn Seoul 143747 South Korea Hanyang Univ Dept Architectural Engn Seoul 133791 South Korea

Several technological problems have to be resolved for LED to be used as a general purpose light source. For instance, LED luminaires have a property of high luminance due to a narrow beam angle and a small volume compared to general light sources. There are several differences between existing luminaires and the intensity distribution of an LED luminaire. An optical engineer has the challenging problem of designing a spatially extended and non-uniform light source. It is difficult for LED luminaires to obtain the target luminous intensity distribution required in a space, because the design process requires much trial and error. And the process also requires much design time. In this study, an optimization algorithm of a numerical model for luminous intensity distribution of planar LED luminaires was developed to find optimized prism angles. This algorithm would used the micro genetic algorithm technique which is the improved form of genetic algorithms. Also, this algorithm is capable of deriving the optimized angle of a prism to achieve the target luminous intensity distribution of planar prism LED luminaires. Therefore, the purpose of this study is to introduce a numerical model of a planar prism LED luminaire and to develop a optimization algorithm that is able to find an optimum luminaire optical design solution using the micro genetic algorithm. (C) 2012 Elsevier B.V. All rights reserved.

关键词： optimization algorithm Numerical model of luminous intensity distribution Micro genetic algorithm Optical design Planer LEDs prism luminaire

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MATLAB-implemented estimation procedure for model-based assessment of hepatic insulin degradation from standard intravenous glucose tolerance test data

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COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2013年第2期110卷 215-225页

作者： Di Nardo, Francesco Mengoni, Michele Morettini, Micaela Univ Politecn Marche Dept Informat Engn I-60131 Ancona Italy

Present study provides a novel MATLAB-based parameter estimation procedure for individual assessment of hepatic insulin degradation (HID) process from standard frequently-sampled intravenous glucose tolerance test (FSIGTT) data. Direct access to the source code, offered by MATLAB, enabled us to design an optimization procedure based on the alternating use of Gauss-Newton's and Levenberg-Marquardt's algorithms, which assures the full convergence of the process and the containment of computational time. Reliability was tested by direct comparison with the application, in eighteen non-diabetic subjects, of well-known kinetic analysis software package SAAM II, and by application on different data. Agreement between MATLAB and SAAM II was warranted by intra-class correlation coefficients >= 0.73;no significant differences between corresponding mean parameter estimates and prediction of HID rate;and consistent residual analysis. Moreover, MATLAB optimization procedure resulted in a significant 51% reduction of CV% for the worst-estimated parameter by SAAM II and in maintaining all model-parameter CV% <20%. In conclusion, our MATLAB-based procedure was suggested as a suitable tool for the individual assessment of HID process. (c) 2012 Elsevier Ireland Ltd. All rights reserved.

关键词： C-peptide and insulin minimal model Indexes of beta-cell responsiveness optimization algorithm Glucose-insulin regulatory system

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Frequency Domain Packet Scheduling with Stability Analysis for 3GPP LTE Uplink

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IEEE TRANSACTIONS ON MOBILE COMPUTING 2013年第12期12卷 2412-2426页

作者： Ren, Fengyuan Xu, Yinsheng Yang, Hongkun Zhang, Jiao Lin, Chuang Tsinghua Univ Dept Comp Sci & Technol Tsinghua Natl Lab Informat Sci & Technol Beijing 100084 Peoples R China Univ Texas Austin Dept Comp Sci Austin TX 78712 USA

In this paper, we investigate the Frequency Domain Packet Scheduling (FDPS) problem for 3GPP Long Term Evolution (LTE) Uplink (UL). Instead of studying a specific scheduling policy, we provide a unified approach to tackle this issue. First, we formalize a general LTE UL FDPS problem, which is suitable for various scheduling policies. Then, we prove that the problem is MAX SNP-hard, which implies that approximation algorithms with constant approximation ratios are the best that we can hope for. Therefore, we design two approximation algorithms, both of which have polynomial runtime. The first algorithm is based on a simple greedy method. The second one is based on the Local Ratio (L-R) technique and it can approximately solve the LTE UL FDPS problem with an approximation ratio of 2. To further analyze the stability of the 2-approximation L-R algorithm, we derive a specific FDPS problem, which incorporates the queue length and channel quality information. We utilize the Lyapunov Drift to prove the L-R algorithm is stable for any (omega(0), epsilon(0))-admissible LTE UL systems. The simulation results indicate good performance of the L-R scheduler.

关键词： Long term evolution (LTE) uplink (UL) frequency domain packet scheduling (FDPS) optimization algorithm approximation ratio local ratio stability analysis Lyapunov drift (omega, epsilon)-admissible

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Frequency Domain Packet Scheduling with MIMO for 3GPP LTE Downlink

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2013年第4期12卷 1752-1761页

作者： Xu, Yinsheng Yang, Hongkun Ren, Fengyuan Lin, Chuang Shen, Xuemin (Sherman) Tsinghua Univ Tsinghua Natl Lab Informat Sci & Technol Dept Comp Sci & Technol Beijing 100084 Peoples R China Univ Texas Austin Dept Comp Sci Austin TX 78712 USA Univ Waterloo Dept Elect & Comp Engn Waterloo ON N2L 3G1 Canada

In this paper, we formalize a general Frequency Domain Packet Scheduling (FDPS) problem for 3GPP LTE Downlink (DL). The DL FDPS problem incorporates the Single-User Multiple Input Multiple Output (SU-MIMO) technique, and can express various scheduling policies, including the Proportional-Fair metric, the MaxWeight scheduling, etc. For LTE DL SU-MIMO, the constraint of selecting only one MIMO mode (transmit diversity or spatial multiplexing) per user in each transmission time interval (TTI) increases the hardness of the FDPS problem. We prove the problem is MAX SNP-hard, which implies approximation algorithms with constant approximation ratios are the best we can expect. Subsequently, we propose an approximation algorithm of polynomial runtime. The solution is based on a greedy method for maximizing a non-decreasing submodular function over a matroid. The algorithm can solve the general DL FDPS problem with an approximation ratio of 4. We implement the proposed algorithm and compare its performance with other well-known schedulers.

关键词： Long Term Evolution (LTE) downlink (DL) frequency domain packet scheduling (FDPS) optimization algorithm approximation ratio submodular function matroid

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Time-Critical Cooperative Path Following of Multiple Unmanned Aerial Vehicles over Time-Varying Networks

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2013年第2期36卷 499-516页

作者： Xargay, E. Kaminer, I. Pascoal, A. Hovakimyan, N. Dobrokhodov, V. Cichella, V. Aguiar, A. P. Ghabcheloo, R. Univ Illinois Dept Aerosp Engn Urbana IL 61801 USA USN Postgrad Sch Dept Mech & Astronaut Engn Monterey CA 93943 USA Inst Super Tecn Lab Robot & Syst Engn & Sci P-1049 Lisbon Portugal Univ Illinois Dept Mech Sci & Engn Urbana IL 61801 USA Tampere Univ Technol Dept Intelligent Hydraul & Automat Tampere 33720 Finland

This paper addresses the problem of steering a fleet of unmanned aerial vehicles along desired three-dimensional paths while meeting stringent spatial and temporal constraints. A representative example is the challenging mission scenario where the unmanned aerial vehicles are tasked to cooperatively execute collision-free maneuvers and arrive at their final destinations at the same time. In the proposed framework, the unmanned aerial vehicles are assigned nominal spatial paths and speed profiles along those, and then the vehicles are requested to execute cooperative path following, rather than open loop trajectory tracking maneuvers. This strategy yields robust behavior against external disturbances by allowing the unmanned aerial vehicles to negotiate their speeds along the paths in response to information exchanged over the supporting communications network. The paper considers the case where the graph that captures the underlying time-varying communications topology is disconnected during some interval of time or even fails to be connected at all times. Conditions are given under which the cooperative path-following closed-loop system is stable. Flight test results of a coordinated road-search mission demonstrate the efficacy of the multi-vehicle cooperative control framework developed in the paper.

关键词： UAV Flight Testing Proportional Control Autopilot Control algorithm Yaw Feedback Control Attitude Control optimization algorithm Nonlinear Control

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Interpretation of Adjoint Solutions for Turbomachinery Flows

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AIAA JOURNAL 2013年第7期51卷 1733-1744页

作者： Marta, Andre C. Shankaran, Sriram Wang, Qiqi Venugopal, Prem Inst Super Tecn Ctr Aerosp Sci & Technol P-1049 Lisbon Portugal Gen Elect Fluid Mech Lab Global Res Ctr Niskayuna NY 12309 USA MIT Dept Aeronaut Cambridge MA 02139 USA Gen Elect Turbomachinery Aerodynam Lab Global Res Ctr Niskayuna NY 12309 USA

Although the mathematical derivation of the adjoint equation;and their numerical implementation is well established, there is scant discussion on the understanding of the adjoint solution by itself. As this is a field solution of similar resolution of the flowfield, there is a wealth of data that can be used for design guidance. The aim is to tie the adjoint solution to the flowfield, which has physical properties. The adjoint solution of four representative cases taken from turbomachinery aerodynamic problems are used to identify the physical insight it provides. The focus is on changes related to geometry, but the changes can also be realized using other inputs to the flow solver (e.g., boundary conditions). It is shown how the adjoint counterpart of the density and velocity field can be used to provide insights into the nature of changes the designer can induce to cause improvement in the performance metric of interest. Discussion on how to use adjoint solutions for problems with constraints to further refine the changes is also included. Finally, a turbine strut problem is discussed where it is not immediately apparent what geometry changes need to be used for further evaluation with optimization algorithms. The adjoint and flow solutions are used to determine the kind of end-wall treatments that reduce the loss. These changes are then implemented to show that the loss is actually reduced. The results in this paper show there is a twofold use of the adjoint method: one for guiding the automatic optimization as such and the second for guiding the designer in the choice of the design space.

关键词： Turbomachinery Design optimization algorithm Mass Flow Eddy Viscosity Reynolds Averaged Navier Stokes Camber Accelerating Flow Turbulence Models Low Pressure Turbine Aerodynamic Shape optimization

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A distributed multi-agent production planning and scheduling framework for mobile robots

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COMPUTERS & INDUSTRIAL ENGINEERING 2013年第1期64卷 19-30页

作者： Giordani, Stefano Lujak, Mann Martinelli, Francesco Univ Roma Tor Vergata Dipartimento Ingn Impresa I-00133 Rome Italy Univ Rey Juan Carlos CETINIA Madrid 28933 Spain Univ Roma Tor Vergata Dipartimento Informat Sistemi & Prod I-00133 Rome Italy

Inspired by the new achievements in mobile robotics having as a result mobile robots able to execute different production tasks, we consider a factory producing a set of distinct products via or with the additional help of mobile robots. This particularly flexible layout requires the definition and the solution of a complex planning and scheduling problem. In order to minimize production costs, dynamic determination of the number of robots for each production task and the individual robot allocation are needed. We propose a solution in terms of a two-level decentralized Multi-Agent System (MAS) framework: at the first, production planning level, agents are tasks which compete for robots (resources at this level);at the second, scheduling level, agents are robots which reallocate themselves among different tasks to satisfy the requests coming from the first level. An iterative auction based negotiation protocol is used at the first level while the second level solves a Multi-Robot Task Allocation (MRTA) problem through a distributed version of the Hungarian Method. A comparison of the results with a centralized approach is presented. (C) 2012 Elsevier Ltd. All rights reserved.

关键词： Production planning and scheduling Dynamic lot sizing Multi-robot task allocation Multi-agent system optimization algorithm

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optimization-based worst-case analysis of a launcher during the atmospheric ascent phase

Optimization-based worst-case analysis of a launcher during ...

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AIAA Guidance, Navigation, and Control (GNC) Conference

作者： Marcos, Andrés de Marina, Hector García Mantini, Valerio Roux, Christophe Bennani, Samir Control Systems Center of Competence Deimos Space SLU Madrid 28035 Spain University of Groningen Netherlands Italy Italy ESA-ESTEC Keplerlaan 1 2201AZ Noordwijk Netherlands

ISBN: (数字)9781624102240

ISBN: (纸本)9781624102240

This article presents the application of optimization-based worst-case search approaches to the VEGA launcher during the P80 ascent phase. Four optimization algorithms are applied covering evolutionary and deterministic global methods as well as their hybrid versions, i.e. mixed with local approaches. A comparison with a traditional Monte Carlo campaign shows that the optimization-based algorithms are much amenable to worst-case search.

关键词： optimization algorithm Aerodynamic Coefficients European Space Agency Search algorithm Solid Propellants Probability Distribution Functions Sensitivity Analysis Deimos Inertial Navigation System Attitude Control System

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Modeling Methods for Identifying Critical Source Areas of Bacteria: Recent Developments and Future Perspectives

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WATER ENVIRONMENT RESEARCH 2013年第3期85卷 259-269页

作者： Tong, Yangbin Deng, Zhiqiang Louisiana State Univ Dept Civil & Environm Engn Baton Rouge LA 70803 USA

Identification of critical source areas of bacteria in a watershed is essential to environmental management and restoration. As a result of the nonpoint and distributed nature of bacterial pollution in watersheds, it is often difficult to identify specific source areas of bacteria for remediation because bacteria collected from different sampling sites might display similar fingerprints. Over the past decade, extensive efforts have been made to identify microbial pollution sources, especially in watersheds. The primary objective of this study was to identify effective methods that can be applied to tracking critical source areas of bacteria in a watershed by a review of recent developments in several modeling methods. Comparisons of the models and their applications revealed that comprehensive watershed-scale source area tracking primarily involves two steps-geographical tracking and mathematical tracking. In terms of geographical tracking, bacterial source locations must be identified to prepare structural best management practices or low impact development for site treatments. For mathematical tracking, the quantity (strength) or release history of bacterial sources must be computed to develop total maximum daily loads (TMDLs) for bacterial load reduction and water quality restoration. Mathematically, source tracking is essentially an inverse modeling issue under uncertainty, requiring inverse modeling combined with a geostatistical method or an optimization algorithm. Consequently, combining biological methods, mathematical models, and sensor technologies (including remote sensing and in-situ sensing) provides an effective approach to identifying critical source locations of bacteria at the watershed-scale.

关键词： bacterial source area tracking optimization algorithm inverse modeling watersheds

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Analysis of Energy Efficiency and Productivity in Dry Process in PCB Manufacturing

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INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING 2013年第7期14卷 1213-1221页

作者： Park, You-Jin Lee, Gyu-Bong Chung Ang Univ Coll Business & Econ Sch Business Adm Seoul 156756 South Korea Korea Inst Ind Technol Ansan 426171 Gyeonggi Do South Korea

Generally the cleaning process in printed circuit board (PCB) manufacturing consists of prewash, wash, rinse, and drying stages. The prewash stage rinses off the gross contaminants from the board before the wash stage. In the wash stage, spray bar and nozzle assembly is used to remove all remaining contaminants. An anti-dragout section exists between the wash and the rinse stages. The use of an air in this section helps prevent any liquid dragout from the wash to the rinse tank. Some cleaners also have a wet isolation that provides further rinsing off the wash water from the PCB. As the last stage of the cleaning process, at drying stage, high temperature and high pressure air is used to get rid of the remaining moist thoroughly By the way, it is known that the dry process consumes a moderately large amount of electric power since high temperature and high pressure air are required in this stage. However, if the due date of a certain PCB product is not too much tight, it would be not necessary to increase the temperature and pressure to proceed with drying Thus, in this research, after collecting the experimental data and modeling the situations with appropriate statistical models, we develop a heuristic approach to the dry process in order to find optimal operating condition which minimizes the energy consumption while meeting the due dates of the ordered products as exactly as possible. Through the heuristic algorithm, that is, interchange-crossover algorithm, we provide an optimal (or near optimal) operating condition which can minimize both the total energy consumption and total penalty cost incurred by earliness and tardiness at the same time. The performance of the other approach is also investigated and compared to that of the developed heuristic approach.

关键词： Dry process PCB manufacturing Energy consumption Statistical model optimization algorithm

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