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Optimized statistical analysis of software trustworthiness attributes

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Science china(Information Sciences) 2012年第11期55卷 2508-2520页

作者： ZHANG Xiao1,LI Wei2,ZHENG ZhiMing1,2 & GUO BingHui1 1Key Laboratory of Mathematics,Informatics and Behavioral Semantics,ministry of education,Beihang university,beijing 100191,china 2State Key Laboratory of Software Development Environment,Beihang university,beijing 100191,china Key Laboratory of Mathematics Informatics and Behavioral Semantics Ministry of Education Beihang University Beijing China State Key Laboratory of Software Development Environment Beihang University Beijing China

Software trustworthiness has become one of the key restrictions for software service quality and the development of the software ***,trustworthiness attributes interlace structured and dynamical coupling relations,which causes great barriers for trustworthiness measurements of large-scale *** to the dynamical evolutionary characteristics of software trustworthiness attributes,this paper proposes a new approach for optimizing the trustworthiness measurement in terms the kernel trustworthiness attributes,and improves a downsize-optimized statistical analysis method for software trustworthiness attributes based on their nonlinear *** improved method considerably simplifies the trustworthiness assessment of largescale *** theoretical analysis and numerical simulations,the feasibility of this method is verified using two typical examples that illustrate the realization of the trustworthiness measurement.

关键词： software trustworthiness kernel attributes optimization statistical analysis

Quenched moderate deviations principle for random walk in random environment

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Science china Mathematics 2010年第8期53卷 1947-1956页

作者： HONG WenMing 1 & WANG HuaMing 1,2 1 Key Laboratory of Mathematics and Complex Systems of ministry of education & School of Mathematical Sciences,beijing Normal university,beijing 100875,china 2 Department of Basic Courses,Business College,beijing Union university,beijing 100025,china Key Laboratory of Mathematics and Complex Systems of ministry of education & School of Mathematical Sciences Beijing Normal University Beijing China Department of Basic Courses Business College Beijing Union University Beijing China

We derive a quenched moderate deviations principle for the one-dimensional nearest random walk in random environment,where the environment is assumed to be stationary and *** approach is based on hitting time decompos... 详细信息

关键词： random walk in random environment moderate deviations principle hitting time

3-D finite element computation and dynamic modal analysis on ultrasonic vibration systems

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Science china(Technological Sciences) 1996年第2期39卷 136-140页

作者：倪金刚张学仁聂景旭(Department of Jet Propulsion 405 beijing university of aeronautics and astronautics beijing 100083 china) Department of Jet Propulsion 405 Beijing Univ. Aero. and Astronaut. Beijing 100083 China

Stress and modal analyses are performed on an ultrasonic vibration system by means of a 3-dimensional finite element computation and dynamic modal analysis code "Algor" The system consists of an edge-cracked specimen linked elastically with one or two amplifying horns which come into resonant longitudinal vibration at *** principle of the ultrasonic fatigue machines and experimental procedures for ultrasonic fatigue crack growth studies are briefly presented.

关键词： ultrasonic fatigue resonant vibration finite element modal analysis.

APPLICATION　OF　DIRECT　BTT　GUIDANCE　LAW　BASED　ON　NONLINEAR　INVERSE　SYSTEM　THEORY　TO　INTEGRATED　FIRE／FLIGHT　SYSTEMS（IFFS）

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Chinese Journal of aeronautics 1996年第4期9卷 305-311页

作者： Ma Xiaojun Zhang Minglian Wen Chuanyuan(Faculty 305, beijing university of aeronautics and astronautics,beijing, china, 100083) Faculty 305 Beijing Univ. Aero. and Astronaut. Beijing 100083 China

To counter BTT guidance mode, new relative motion equations of the targetaircraft and the attack aircraft are proposed. The inverse system theory of the nonlinearcontrol is used, and the direct BTT-180 guidance command is solved, which can operatethe attack aircraft to automatically complete the flight mission of the preceding stage ofthe terminal weapon delivery, and thus the automatic attack is extended from the stage ofthe terminal weapon delivery to the preceding stage of the terminal weapon delivery.

关键词： fire control flight control nonlinear systems inverse system direct BTT guidance law automatic control attack

PERFORMANCE EVALUATION OF SEVERAL FUSION APPROACHES FOR CCD/SAR IMAGES

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Chinese Geographical Science 2003年第1期13卷 91-96页

作者： WANG Yan-li, CHEN Zhe(School of Automation Science and Electrical Engineering, beijing university of aeronautics and astronautics, beijing 100083, P. R. china) School of Automation Science and Electrical Engineering Beijing University of Aeronautics and Asturonautics 北京

Several image fusion approaches for CCD/SAR images are studied and the performance evaluation of these fusion approaches is completed in this paper. Firstly, the preprocessing of CCD/SAR images before fusion is fulfilled. Then, the image fusion methods including linear superposition, nonlinear operator method and multiresolution methods, of which the multiresolution methods include Laplacian pyramid, ratio pyramid, contrast pyramid, gradient pyramid, morphological pyramid and discrete wavelet transform, are adopted to fuse two types of images. Lastly, the four performance measures, standard deviation, entropy, cross entropy and spatial frequency, are calculated to compare the fusion results by different fusion approaches in this paper. Experimental results show that contrast pyramid, morphology pyramid and discrete wavelet transformation in multiresolution approaches are more suitable for CCD/SAR image fusion than other ones proposed in this paper and the objective performance evaluation of CCD/SAR image fusion approaches are effective.

关键词： image fusion performance evaluation CCD image SAR image

A Circular aperture-array structure optical system for digital sun sensor

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Optoelectronics Letters 2008年第1期4卷 62-65页

作者： WEN Zhi-ming,JIANG Jie, ZHANG Guang-jun,and FAN Qiao-yun Key Laboratory for Precision Opto-mechatronic. Techonology of ministry of education ,beijing university of aeronautics and astronautics, beijing 100083,china Key Laboratory for Precision Opto-mechatronic. Techonology of ministry of education Beijing University of Aeronautics and Astronautics Beijing China

Based on the first type of Rayleigh Sommerfeld diffraction formula, an imaging model of circular aperture-array structure digital sun sensor optical system is developed. Then a 6×6 circular aperture-array structure optical system is designed. The results of numerical simulation show that the optical system is designed well and is conformed to the requirements of miniaturization and high accuracy of sun sensor.

关键词：数字太阳传感器圆孔结构光学系统光衍射角度测量

Two Optical Techniques Appropriate for Visualizing the Steady/Unsteady VorticalFlow past a Highly Swept Delta-Wing Equipped with Double Vortex-Flaps in Low and High Speed Wind-TUnnel

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Communications in Nonlinear Science and Numerical Simulation 1998年第3期3卷 167-172页

作者： Gong NI Jieke LU and Dingding XIN(beijing Institute of Aerodynamics, beijing 100074, china)(beijing university of aeronautics and astronautics. Institute of Fluid Mechanics,beijing 100083, china)E-mail: xindd@*** beijing Institute of Aerodynamics Beijing 100074 China beijing Univ. Aero. and Astronaut. Institute of Fluid Mechanics Beijing 100083 China

For a better understanding of the vortical flow past a highly swept deltawing equipped with double vortex-flaps, two optical techniques including the Laser-lightsheet with artificial particals put in the test-section and the Schlieren photography wereused for steady/unsteady flow visualization in the low and high speed wind-tunnel respectively. Since these techniques are seldom used for vortical flow visualization in thementioned cases in our country, our success has the significance to indicate that they areappropriate for visualizing the development, muteal interaction and break-down of thevortices appear in the complex flow field. In this paper, besides the experimental procedure, mints and demerits of these two techniques are discussed through comparisons.

关键词： optical emchnique flow visualization steady/unsteady flow double vortex flap

Dimension reduction based on weighted variance estimate

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Science china Mathematics 2009年第3期52卷 539-560页

作者： ZHAO JunLong1 & XU XingZhong2 1 Department of Mathematics, Beihang university Laboratory of Mathematics, Information and Behavior of the ministry of education, beijing 100083, china 2 Department of Mathematics, beijing Institute of Technology, beijing 100081, china Department of Mathematics Beihang University Laboratory of Mathematics Information and Behavior of the Ministry of Education Beijing China Department of Mathematics Beijing Institute of Technology Beijing China

In this paper, we propose a new estimate for dimension reduction, called the weighted variance estimate (WVE), which includes Sliced Average Variance Estimate (SAVE) as a special case. Bootstrap method is used to select the best estimate from the WVE and to estimate the structure dimension. And this selected best estimate usually performs better than the existing methods such as Sliced Inverse Regression (SIR), SAVE, etc. Many methods such as SIR, SAVE, etc. usually put the same weight on each observation to estimate central subspace (CS). By introducing a weight function, WVE puts different weights on different observations according to distance of observations from CS. The weight function makes WVE have very good performance in general and complicated situations, for example, the distribution of regressor deviating severely from elliptical distribution which is the base of many methods, such as SIR, etc. And compared with many existing methods, WVE is insensitive to the distribution of the regressor. The consistency of the WVE is established. Simulations to compare the performances of WVE with other existing methods confirm the advantage of WVE.

关键词： central subspace contour regression sliced average variance estimate sliced inverse regression sufficient dimension reduction weight function 62G08 62H05

A STUDY ON THE MARGINAL ANALYSIS METHOD FOR THE AIRLINE YIELD MANAGEMENT

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Chinese Journal of aeronautics 1992年第4期 270-276页

作者： Guan Jian-cheng(beijing university of aeronautics and astronautics,beijing,100083,china)

The current situation and the history of two-fare-class seat inventory control problemfor the airline yield management in the air transportation of the passengers are *** a new marginal analytical method determining the optimal allotment forthe two-class problem is presented with an emphasis on the theoretical aspects of the problemas compared with the traditional *** on the fact that the passengers’ demandnumber is a discrete random variable the formula deduction is demonstrated *** formula obtained in this paper which shows that the optimal seat allotment relatesto the distributions of both high-fare demand and low-fare demand has made someimprovements for the traditional formulae in this *** the formula deductedin this paper to the traditional formulae the results of the computational example of thenew formula show that the method is more accurate and also practical.

关键词： A STUDY ON THE MARGINAL ANALYSIS METHOD FOR THE AIRLINE YIELD MANAGEMENT high