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Gain-Scheduling Control Design in the Presence of Hidden Coupling Terms

JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2016年第8期39卷 1871-U254页

作者： Lhachemi, H. Saussie, D. Zhu, G. Ecole Polytech Dept Elect Engn Montreal PQ H3T 1J4 Canada

A novel method to handle the hidden coupling terms that naturally arise in the control of a nonlinear plant when an endogenous variable is used as a scheduling parameter was proposed. The proposed approach includes them in the design process with an a priori selection of the scheduling functions. This procedure is generic enough to be applied to a great variety of nonlinear systems in a systematic manner. The efficiency of the proposed approach has been demonstrated on the control of a pitch-axis missile benchmark problem, which has been solved by a nonsmootha* optimization algorithm to yield a robust and self-scheduled controller. Numerical simulations show that the resulting controller can achieve a significant performance improvement while satisfying the robustness requirements when faced with a variety of uncertainties.

关键词： State Space Representation Aerodynamic Coefficients Angle of Attack Nonlinear Systems optimization algorithm Nonlinear Feedback Autopilot Numerical Simulation Frequency Domain Missile Control

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Horizontal wind velocity retrieval using a Levenberg-Marquardt algorithm for an airborne wind lidar

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JOURNAL OF APPLIED REMOTE SENSING 2016年第2期10卷 026009-1-026009-10页

作者： Zhu, Jinshan Li, Zhigang Liu, Zhishen Shandong Univ Sci & Technol Coll Geomat 579 Qianwangang Rd Qingdao 266590 Peoples R China Natl Adm Surveying Mapping & Geoinformat China Key Lab Surveying & Mapping Technol Isl & Reef 579 Qianwangang Rd Qingdao 266590 Peoples R China Ludong Univ Sch Phys & Optoelect Engn 186 Middle Hongqi Rd Yantai 264025 Peoples R China Ocean Univ China Ocean Remote Sensing Inst 5 Yushan Rd Qingdao 266003 Peoples R China

We established a model for an airborne wind lidar. Numericala* optimization algorithms should be used to solve this nonlinear model. We designed a Levenberg-Marquardt (L-M) algorithm and tested it with the modeled data. The retrieved velocity and the true velocity agree very well, and the adjusted R-2 is 0.99947. We have carried out an airborne coherent wind lidar experiment in January 2015, and we used the model and the L-M algorithm to process the wind lidar experiment data, and compared the retrieved results with the radiosonde wind profile. The consistency is very good, especially at an altitude above 1.8 km. We may speculate that when the atmosphere flows are not so dramatic, the lidar and the radiosonde measurements are strictly synchronous, it is possible to retrieve horizontal wind speeds and directions consistently with the radiosonde using our wind lidar model and the L-M algorithm. (c) 2016 Society of Photo-Optical Instrumentation Engineers (SPIE)

关键词： airborne wind lidar Doppler optimization algorithm Levenberg-Marquardt algorithm

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Study on the Prediction of Troposcatter Transmission Loss

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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 2016年第3期64卷 1071-1079页

作者： Li, Lei Wu, Zhen-Sen Lin, Le-Ke Zhang, Rui Zhao, Zhen-Wei Xidian Univ Sch Phys & Optoelect Engn Xian 710071 Peoples R China CRIRP Natl Key Lab Electromagnet Environm Qingdao Peoples R China

In this article, a novel semiempirical average annual troposcatter transmission loss prediction model is presented. The model is generated by optimizing the correlation coefficients of propagation path conditions utilizing the moderna* optimization algorithm. The statistical relativities of troposcatter transmission loss as captured by changing frequency, path length, scatter angle, and meteorological condition are each analyzed using the terrestrial trans-horizon propagation loss data banks released by the International Telecommunication Union (ITU). For the percentages of time transmission loss not falling below 50%, the model is combined with the model of anomalous propagation mechanism introduced in the Recommendation ITU-R P.2001. The prediction results of this new troposcatter model are compared with other troposcatter models and with the trans-horizon propagation loss data banks. The comparisons show that the new model has a better estimated accuracy.

关键词： Average year optimization algorithm prediction model trans-horizon propagation transmission loss troposcatter

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Modulation of Directionality of Infrared Signatures Based on Anisotropic Emission Behavior

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JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER 2016年第4期30卷 804-813页

作者： Huang, Yong Cui, Xue Beihang Univ Fundamental Sci Ergon & Environm Control Lab Sch Aeronaut Sci & Engn Beijing Univ Aeronaut & Astronaut Mailbox 50537 Xueyuan Rd Beijing 100191 Peoples R China Beihang Univ Fundamental Sci Ergon & Environm Control Lab Sch Aeronaut Sci & Engn Beijing 100191 Peoples R China

A technique for modulating the directional characteristics of the target's infrared signatures based on the anisotropic emission behavior of the target surface is proposed. The integrated infrared transmission model from target to detector is established by matrices. Through the single-, multi-, and omni-directional infrared signature optimization analyses, the effectiveness of the proposed modulation technique is demonstrated and the following conclusions were reached: 1) Because the hemispherical emissivity remains constant, modulating the angular emission patterns of the target surface can enhance or reduce the target's infrared signature level received by the detector. 2) It is possible to adjust the directionality of infrared signatures by virtue of anisotropic emission behavior, generating appreciable peak signals in the desired directions or reducing the infrared signals in the infrared -threatening directions. 3) The optimizing effects upon the directionality of infrared signatures are highly dependent on the geometric features of target and hemispherical emissivity: the smaller the hemispherical emissivity is, the better the effects are.

关键词： Radiation Properties Aircraft Configurations optimization algorithm Transmittance Horizontal Stabilizers Emissive Power Aircraft Wings Spline Interpolation Euler Angles Aerodynamic Heating

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Decentralized Cooperative Control Methods for the Modified Weapon-Target Assignment Problem

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2016年第9期39卷 1934-1948页

作者： Volle, Kyle Rogers, Jonathan Brink, Kevin Georgia Inst Technol Sch Mech Engn Atlanta GA 30332 USA US Air Force Res Lab Munit Directorate Eglin AFB FL 32542 USA

Weapon-target assignment is a combinatorial optimization problem in which a set of weapons must selectively engage a set of targets. In its decentralized form, it is also an important problem in autonomous multi-agent robotics. In this work, decentralized methods are explored for a modified weapon-target assignment problem in which weapons seek to achieve a prespecified probability of kill on each target. Three novel cost functions are proposed that, in cases with low agent-to-target ratios, induce behaviors that may be preferable to the behaviors induced by classical cost functions. The performance of these proposed cost functions is explored in simulation of both homogeneous and heterogeneous engagement scenarios using airborne autonomous weapons. Simulation results demonstrate that the proposed cost functions achieve desired behaviors in cases with low agent-to-target ratios where efficient use of weapons is particularly important.

关键词： Airborne Autonomous Weapons Robotics Annealing algorithm Performance optimization algorithm Stochastic optimization Mechanism Design Cost Reduction Search algorithm Unmanned Aerial Vehicle

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Shaping Radar Ambiguity Function by L-Phase Unimodular Sequence

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IEEE SENSORS JOURNAL 2016年第14期16卷 5648-5659页

作者： Zhang, Jindong Shi, Changli Qiu, Xiaoyan Wu, Yue Nanjing Univ Aeronaut & Astronaut Coll Elect & Informat Engn Nanjing 210016 Jiangsu Peoples R China Nanjing Univ Aeronaut & Astronaut Nanjing 210016 Jiangsu Peoples R China

In this paper, we discuss the ambiguity function (AF) synthesis problem for unimodular sequences, which are widely used in radar/sonar and communication systems. Notions of discrete-time ambiguity function and discrete ambiguity function (DAF) are defined, and the corresponding properties are also discussed for unimodular sequences. Depending on these properties, two algorithms are proposed to synthesize the DAF of the unimodular sequence by minimizing the squared error between a desired complex/real function and a realizable one over L-phase alphabet. To break the volume invariant constraint of a single sequence's AF, multi-sequences are also considered to be optimized simultaneously to suppress sidelobes of ambiguity surface. Numerical examples show the effectiveness of the proposed algorithms in synthesizing unimodular sequence with a desired AF, and typical polyphase sequences can be well approximated by eight-phase unimodular sequences from the viewpoint of DAF.

关键词： Ambiguity function shaping unimodular sequence optimization algorithm discrete-time ambiguity function discrete ambiguity function

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Modified Compact Genetic algorithm for Thinned Array Synthesis

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IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS 2016年 15卷 1105-1108页

作者： Ha, B. V. Mussetta, M. Pirinoli, P. Zich, R. E. Catholic Univ Louvain ICTEAM B-1348 Louvain La Neuve Belgium Politecn Milan Dipartimento Energia I-20156 Milan Italy Politecn Torino Dipartimento Elettron & Telecomunicaz I-10129 Turin Italy

In this letter, a newa* optimization algorithm, the Modified compact Genetic algorithm (M-cGA) is introduced and applied to the synthesis of thinned arrays. The M-cGA has been derived from the compact Genetic algorithm (cGA), properly modified and improved by implementing more than one probability vector (PV) and adding suitable learning scheme between these PVs. The so-obtained algorithm has been applied to the optimized synthesis of different-size linear and planar thinned arrays: In all the considered cases, it outperforms not only the cGA, but also the other optimization schemes previously applied to this kind of problem, both in terms of goodness of the solution (minimization of the peak sidelobe level) and of computational cost.

关键词： Antenna compact genetic algorithm optimization algorithm thinned array

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Improvements to Time of Closest Approach Calculation

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2016年第9期39卷 1967-1979页

作者： Denenberg, Elad Gurfil, Pini Technion Israel Inst Technol Technion Autonomous Syst & Robot Program IL-3200003 Haifa Israel Technion Israel Inst Technol Fac Aerosp Engn IL-3200003 Haifa Israel

Space debris constitutes a major and growing threat to space missions. To assess the probability of collision, the time of closest approach between the spacecraft and the debris must first be calculated. This paper presents three new methods for the calculation of the time of closest approach. The first is a surrogate-baseda* optimization algorithm, using the Alfano-Negron Close Approach Software as the model, allowing a compromise between calculation speed and accuracy. The second is a generalization of this software, treating a cloud of debris as a continuous object and searching for the time of closest approach over initial conditions as well as time. The third uses Alfano-Negron Close Approach Software generalization as a model for surrogate-based optimization. Using the third method, a strategy for safe operation of a spacecraft cluster in a debris-rich environment is proposed. All methods are demonstrated and compared. It is shown that Alfano-Negron Close Approach Software and the generalization thereof are very fast in estimating the time of closest approach, and that the surrogate-baseda* optimization algorithms are somewhat slower, but are highly accurate.

关键词： optimization algorithm Space Missions Space Debris Satellite Formation Flying FreeFlyer Fengyun Periapsis Singular Value Decomposition algorithm Performance Orbital Elements

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Structure and bonding in quaternary Ag-Au-Pd-Pt clusters

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JOURNAL OF ALLOYS AND COMPOUNDS 2016年第0期687卷 115-120页

作者： Wu, Xia Wei, Zheng Liu, Qiman Pang, Tao Wu, Genhua Anqing Normal Univ Sch Chem & Chem Engn Anqing 246011 Peoples R China Anqing Normal Univ Anhui Prov Lab Optoelect & Magnetism Funct Mat Anqing 246011 Peoples R China

Structural optimization of quaternary Ag-Au-Pd-Pt clusters up to 38 atoms is performed using adaptive immunea* optimization algorithm, and the Gupta many-body potential is adopted to model interatomic interaction. By fixing the atomic number of three types and varying the number of one type in quaternary clusters, geometrical effects by different types of noble metals are investigated. Results show that most configurations present the growth pattern based on the 19-atom double icosahedra, however, the structural transition model induced by increasing the number of the fourth noble atom is found to be different. Furthermore, the order parameter indicates that in quaternary clusters Ag and Au atoms mainly occupy the surface sites, Pd atoms tend to be in the middle shell, and the inner shell is located by Pt atoms. The study of the number of bonds indicates that Ag and Au atoms prefer scattering and forming a circle on the surface, respectively. (C) 2016 Elsevier B.V. All rights reserved.

关键词： Ag-Au-Pd-Pt clusters Stable structures optimization algorithm Growth pattern

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Energy systems in cost-optimized design of nearly zero-energy buildings

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AUTOMATION IN CONSTRUCTION 2016年第Oct.期70卷 109-127页

作者： Ferrara, Maria Fabrizio, Enrico Virgone, Joseph Filippi, Marco Politecn Torino DENERG Corso Duca Abruzzi 24 I-10129 Turin Italy Univ Turin DISAFA Largo Paolo Braccini 2 I-10095 Grugliasco TO Italy Univ Lyon 1 INSA Lyon CETHIL UMR5008 9 Rue Phys F-69621 Villeurbanne France

Cost optimization is one of the key elements of the EU regulatory framework concerning the energy performance of buildings. From this economic point of view, the optimum occurs when the global cost over the lifecycle of a building is minimized, and the cost-optimal energy performance level is that related to the minimum global cost. To determine this cost-optimal level by evaluating a great number of design alternatives, it is necessary to exploit automated optimization search procedures. The work presented here concerns the application of cost optimal methodology, as defined by European regulation, to a low-consumption single-family house in France. The calculation is performed through an iterative input-output process in a computing environment that combines TRNSYS (R), transient system simulation tool, with GenOpt (R), generic optimization program. The methodology that was adopted allowed around ten thousand building configurations to be simulated in a reasonable computational time. The paper focuses on how the energy system affects the technical and economic optimal design solutions of the building in two different French climate conditions. (C) 2016 Elsevier B.V. All rights reserved.

关键词： EPBD recast Cost-optimal analysis Dynamic building simulation Automated optimization optimization algorithm Particle swarm optimization France Cost function Single family house Design parameters

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