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Simultaneous determination of aerosol optical thickness and exponent of Junge power law from satellite measurements of two near-infrared bands over the ocean

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OPTICS EXPRESS 2007年第8期15卷 5227-5236页

作者： Xu, Qingshan Wei, Heli Rao, Ruizhong Hu, Huanling Chinese Acad Sci Anhui Inst Opt & Fine Mech Hefei 230031 Anhui Peoples R China

An iterative algorithm is presented in this study for simultaneous determination of both the aerosol optical thickness and the exponent of the Junge power law from the total reflectance data of two satellite-based, near-infrared bands over the ocean. The atmospheric aerosol model is assumed as the Junge power-law size distribution in retrieval of the data. Numerical simulations show that relative errors in retrieval of the aerosol optical thickness and the exponent of the Junge power law are less than 5% when the actual atmospheric aerosol follows the Junge power-law size distribution. For other aerosol size distributions, relative errors of the aerosol optical thickness are less than approximately 10%. The proposed method is applied to a case study of the data of two near-infrared channels of the Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) over the East China Sea area. The results show that reasonable spatial distribution of the exponent of the Junge law and the aerosol optical thickness may be obtained on a pixel-by-pixel basis through use of the proposed retrieval algorithm. (c) 2007 Optical Society of America.

关键词： .actual Distributions reflectance Near-Infrared Numerical Simulations size distribution iterative algorithm relative errors SeaWiFS aerosol optical Simultaneous determination Junge power law atmospheric aerosol Junge power-law aerosol size

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Assessment of critical fuel configurations using robust flutter analysis

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JOURNAL OF AIRCRAFT 2007年第6期44卷 2034-2039页

作者： Heinze, Sebastian Royal Inst Technol Div Flight Dynam S-10044 Stockholm Sweden

An approach to assess critical fuel configurations using robust flutter analysis is presented. A realistic aircraft model is considered to demonstrate how an available finite element model can be adapted to easily apply robust flutter analysis with respect to structural variations such as fuel-level variations. The study shows that standard analysis tools can be used to efficiently generate the system data that are required to perform robust flutter analysis. The mu-k method is used to compute the worst-case flutter speed, and the corresponding worst-case fuel configuration is found. The main advantage of the proposed approach is that mu analysis guarantees robustness with respect to all possible fuel configurations represented by the tank model.

关键词： Flutter Analysis Fuels Finite Element Modeling Nastran iterative algorithm Numerical Modeling Aircraft Configurations Subsonic Aircraft Airspeed Control Surfaces

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Electrical capacitance volume tomography with high contrast dielectrics using a cuboid sensor geometry

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MEASUREMENT SCIENCE AND TECHNOLOGY 2007年第5期18卷 1511-1520页

作者： Nurge, Mark A. NASA Kennedy Space Ctr Kennedy Space Ctr FL 32899 USA

An electrical capacitance volume tomography system has been created for use with a new image reconstruction algorithm capable of imaging high contrast dielectric distributions. The electrode geometry consists of two 4 x 4 parallel planes of copper conductors connected through custom built switch electronics to a commercially available capacitance to digital converter. Typical electrical capacitance tomography ( ECT) systems rely solely on mutual capacitance readings to reconstruct images of dielectric distributions. This paper presents a method of reconstructing images of high contrast dielectric materials using only the self-capacitance measurements. By constraining the unknown dielectric material to one of two values, the inverse problem is no longer ill-determined. Resolution becomes limited only by the accuracy and resolution of the measurement circuitry. Images were reconstructed using this method with both synthetic and real data acquired using an aluminium structure inserted at different positions within the sensing region. Comparisons with standard two-dimensional ECT systems highlight the capabilities and limitations of the electronics and reconstruction algorithm.

关键词： electrical capacitance volume tomography electrical capacitance tomography image reconstruction high contrast dielectrics iterative algorithm inverse problem self-capacitance

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g-η-Monotone mapping and resolvent operator technique for solving generalized implicit variational-like inclusions

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Applied Mathematics and Mechanics(English Edition) 2007年第1期28卷 11-18页

作者：张清邦丁协平 College of Applied Sciences Beijing University of Technology Beijing 100022 P. R. China College of Mathematics and Software Science Sichuan Normal UniversityChengdu 610066 P. R. China

A new class of g-η-monotone mappings and a class of generalized implicit variational-like inclusions involving g-η-monotone mappings are introduced. The resolvent operator of g-η-monotone mappings is defined and its Lipschitz continuity is presented, An iterative algorithm for approximating the solutions of generalized implicit wriational- like inclusions is suggested and analyzed. The convergence of iterative sequences generated by the algorithm is also proved,

关键词： g-η-monotone mapping resolvent operator generalized implicit variational-like inclusion iterative algorithm

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algorithm for exploiting channel time selectivity in pilot-aided MIMO systems

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IET COMMUNICATIONS 2007年第6期1卷 1267-1273页

作者： Chin, W. H. Ward, D. B. Constantinides, A. G. Inst Infocomm Res Singapore 119613 Singapore Imperial Coll London Dept Elect & Elect Engn London SW7 2BT England

The problem of channel estimation and symbol detection in fast fading channels using multiple antennas is dealt with. This is one of the many challenges faced by extending spatial multiplexing to mobile terminals. A commonly used method of resolving this problem is pilot-aided channel interpolation. An iterative algorithm that substantially improves the performance of pilot-aided MIMO channel interpolation systems is proposed. The algorithm involves alternating projection of parameters onto different sub-spaces so as to exploit the time selectivity of the channel to improve the quality of symbol detection. Simulations have shown that the algorithm, when applied to any interpolation scheme, improves the bit error performance of the system significantly.

关键词： iterative methods pilot-aided MIMO system pilot-aided channel interpolation multiple antennas iterative algorithm bit error performance fading channels fading channel error statistics channel estimation interpolation antenna arrays MIMO communication

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Existence and algorithm of Solutions for Generalized Set-valued Strongly Nonlinear Mixed Variational-like Type Inequalities

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Journal of Donghua University(English Edition) 2007年第4期24卷 467-472,477页

作者：胡梦瑜曾六川陈珊敏 Department of Mathematics Shanghai Normal University Department of Applied Mathematics Donghua University

The auxiliary principle technique is extended to study a class of generalized set-valued strongly nonlinear mixed variational-like type inequalities. Firstly, the existence of solutions to the auxiliary problems for this class of generalized set-valued strongly nonlinear mixed variational-like type inequalities is shown. Secondly, the iterative algorithm for solving this class of generalized set-valued strongly nonlinear mixed variational-like type inequalities is given by using this existence result. Finally, the strong convergence of iterative sequences generated by the algorithm is proven. The present results improve, generalize and modify the earlier and recent ones obtained previously by some authors in the literature.

关键词： iterative algorithm set-valued mapping existence convergence Hilbert space

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algorithm for missile detection from radar data

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JOURNAL OF SPACECRAFT AND ROCKETS 2007年第1期44卷 276-280页

作者： Piergentili, Fabrizio Teofilatto, Paolo Univ Roma La Sapienza I-00184 Rome Italy

A simplified analytic solution of the boost phase of a missile is appliedhere to estimate the four missile fundamental parameters and the six state variables. Such ananalytical estimate provides a suitable guess for the convergence of a postprocessing algorithmbased on the maximum likelihood estimate method. An extended Kalman filter has been applied to thesame problem; in the present case (search radar with low frequency rate), better outcomes have beenachieved implementing the filter, considering missile parameters obtained by maximum likelihoodestimate. Besides, a combined use of batch-detection algorithms is proposed here for the boostedphase and real-time detection algorithms for the ballistic and reentry phases.

关键词： Missiles Radar Data Extended Kalman Filter Thrust to Weight Ratio Ballistic Coefficient Flight Path Angle Histograms Gravity Turn Propellant iterative algorithm

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iterative approximation of a solution of multi-valued variational-like inclusion in Banach spaces:: A P-η-proximal-point mapping approach

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JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS 2007年第1期325卷 665-674页

作者： Kazmi, K. R. Khan, F. A. Aligarh Muslim Univ Dept Math Aligarh 202002 Uttar Pradesh India

In this paper, we introduce a class of P-eta-accretive mappings, an extension of eta-m-accretive mappings [C.E. Chidume, K.R. Kazmi, H. Zegeye, iterative approximation of a solution of a general variational-like inclusion in Banach spaces, Int. J. Math. Math. Sci. 22 (2004) 1159-1168] and P-accretive mappings [Y.-P. Fang, N.-J. Huang, H-accretive operators and resolvent operator technique for solving variational inclusions in Banach spaces, Appl. Math. Lett. 17 (2004) 647-653], in real Banach spaces. We prove some properties of P-eta-accretive mappings and give the notion of proximal-point mapping, termed as P-eta-proximal-point mapping, associated with P-eta-accretive mapping. Further, using P-eta-proximal-point mapping technique, we prove the existence of solution and discuss the convergence analysis of iterative algorithm, for multi-valued variational-like inclusions in real Banach space. The theorems presented in this paper extend and improve many known results in the literature. (c) 2006 Elsevier Inc. All rights reserved.

关键词： multi-valued variational-like inclusion P-eta-accretive mapping P-eta-proximal-point mapping iterative algorithm convergence analysis

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NEW PROXIMAL algorithmS FOR A CLASS OF (A, eta)-ACCRETIVE VARIATIONAL INCLUSION PROBLEMS WITH NON-ACCRETIVE SET-VALUED MAPPINGS

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JOURNAL OF APPLIED MATHEMATICS AND COMPUTING 2007年第1-2期25卷 255-267页

作者： Lan, Heng-You Sichuan Univ Sci & Engn Dept Math Zigong 643000 Sichuan Peoples R China

In this work, by using Xu's inequality, Nalder's results, the notion of (A, eta)-accretive mappings and the new resolvent operator technique associated with (A, eta)-accretive mappings due to Lan et al., we study the existence of solutions for a new class of (A, eta)-accretive variational inclusion problems with non-accretive set-valued mappings and the convergence of the iterative sequences generated by the algorithms in Banach spaces. Our results are new and extend, improve and unify the corresponding results in this field.

关键词： (A, eta)-accretive mapping resolvent operator technique relaxed cocoercive mapping and non-accretive set-valued mapping iterative algorithm convergence

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Row-column soft-decision feedback algorithm for two-dimensional intersymbol interference

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IEEE SIGNAL PROCESSING LETTERS 2007年第7期14卷 433-436页

作者： Cheng, Taikun Belzer, Benjamin J. Sivakumar, Krishnamoorthy Washington State Univ Sch Elect Engn & Comp Sci Pullman WA 99164 USA

We present a novel iterative row-column soft decision feedback algorithm (IRCSDFA) for detection of binary images corrupted by 2-D intersymbol interference and additive white Gaussian noise. The algorithm exchanges weighted soft information between row and column maximum a posteriori (MAP) detectors. 7 Each MAP detector exploits soft-decision feedback from previously processed rows or columns. The new algorithm gains about 0.3 dB over the previously best published results for the 2 x 2 averaging mask. For a non-separable 3 x 3 mask, the IRCSDFA gains 0.8 dB over a previous soft-input/soft-output iterative algorithm which decomposes the 2-D convolution into 1-D row and column operations.

关键词： iterative algorithm soft decision feedback 2-D intersymbol interference

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