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Success probability orientated optimization model for resource allocation of the technological innovation multi-project system

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Journal of Systems Engineering and Electronics 2016年第6期27卷 1227-1237页

作者： Weixu Dai Weiwei Wu Bo Yu Yunhao Zhu School of Management Harbin Institute of Technology Institute of Spacecraft Systems Engineering China Academy of Space Technology

A success probability orientated optimization model for resource allocation of the technological innovation multi-project system is studied. Based on the definition of the technological innovation multi-project system, the leveling optimization of cost and success probability is set as the objective of resource allocation. The cost function and the probability function of the optimization model are constructed. Then the objective function of the model is constructed and the solving process is explained. The model is applied to the resource allocation of an enterprise's technological innovation multi-project system. The results show that the proposed model is more effective in rational resource allocation, and is more applicable in maximizing the utility of the technological innovation multi-project system. ? 2016 Beijing Institute of Aerospace Information.

关键词： cost functions Optimization Probability

Novel iteration-free blind phase noise estimation for coherent optical OFDM

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Chinese Optics Letters 2014年第12期12卷 19-23页

作者：任宏亮蔡嘉兴卢瑾温浩薛林林覃亚丽郭淑琴周守利胡卫生 College of Information Engineering Zhejiang University of Technology State Key Laboratories of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University

We propose a novel iteration-free blind phase noise estimation scheme for coherent optical orthogonal frequency division multiplexing （CO-OFDM） systems. In the new algorithm, the cost function is selected as the similar expression with real and imaginary parts as that in the modified constant modulus algorithm, and the new cost function is derived under some assumptions, where it is infinitely approximated by the sine and cosine functions. By means of the analytical formula of the cost function, the initial coarse common phase error can be obtained with only some samples, where the algorithm avoids computational complexity of conventional blind phase noise compensation scheme. In CO-OFDM systems with high-order modulation format （32 quadrature amplitude modulation） and narrow linewidth lasers, it is proved by the simulation results that the nhase noise can be effectively compensated with the proposed blind estimation method.

关键词： Amplitude modulation Computational complexity Cosine transforms cost functions costs Error compensation Frequency division multiplexing Frequency estimation Iterative methods Modulation Optical fiber communication Orthogonal frequency division multiplexing Quadrature amplitude modulation

Restoration of solar and star images with phase diversity-based blind deconvolution

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Chinese Optics Letters 2007年第4期5卷 201-203页

作者：李强廖胜魏宏刚沈忙作 State Key Laboratory of Optical Technologies for Microfabrication Institute of Optics and Electronics Chinese Academy of Sciences

The images recorded by a ground-based telescope are often degraded by atmospheric turbulence and the aberration of the optical system. Phase diversity-based blind deconvolution is an effective post-processing method that can be used to overcome the turbulence-induced degradation. The method uses an ensemble of short-exposure images obtained simultaneously from multiple cameras to jointly estimate the object and the wavefront distribution on pupil. Based on signal estimation theory and optimization theory, we derive the cost function and solve the large-scale optimization problem using a limited memory BroydenFletcher-Goldfarb-Shanno （L-BFGS） method. We apply the method to the turbulence-degraded images generated with computer, the solar images acquired with the swedish vacuum solar telescope （SVST, 0.475 m） in La Palma and the star images collected with 1.2-m telescope in Yunnan Observatory. In order to avoid edge effect in the restoration of the solar images, a modified Hanning apodized window is adopted. The star image still can be restored when the defocus distance is measured inaccurately. The restored results demonstrate that the method is efficient for removing the effect of turbulence and reconstructing the point-like or extended objects.

关键词： Aberrations Atmospheric turbulence cost functions Deconvolution Optical systems Wavefronts

Exploring an Efficient Approach for Active Noise Control Systems with Online Secondary Path Modeling

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Exploring an Efficient Approach for Active Noise Control Sys...

Launching Organizations toward Growth and Profit through Focused Innovation:A Critical Study into Powerful Microeconomic Concepts

2011年亚太信号与信息处理协会年会

作者： Akihisa OISHI Muhammad Tahir AKHTAR Wataru MITSUHASHI Department of Communication Engineering and Informatics The University of Electro-Communications 1-5-1 Chofugaoka Chofu 182-8585 Tokyo Japan The Center for Frontier Science and Engineering (CFSE) The University of Electro-Communications 1-5-1 Chofugaoka Chofu 182-8585 Tokyo Japan

In this paper, we explore a new approach for controlled injection of probe noise for secondary path modeling （SPM） in the feedforward active noise control （ANC） systems. The existing approaches employ a single adaptive FIR filter for SPM in ANC systems. In the proposed approach, a separate filter temporarily holds a replica of the tap-weights of the SPM filter. Furthermore, a cost function-on the basis of difference of error powers from the two filters-is evaluated for keeping or suspending the injection of the probe noise. If the acoustic characteristics are changed in the secondary path after suspending the injection, outliers in the error signal from the SPM filter are detected for restarting the injection. Numerical simulations show that the noise-reduction performance is improved by introducing the proposed approach for the ANC systems.

关键词： ERROR SIGNAL cost functions Scanning Probe Microscopy Acid neutralising capacity Injections Filters control systems Active noise control Acoustic properties

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Launching Organizations toward Growth and Profit through Foc...