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Testability evaluation using prior information of multiple sources

Chinese Journal of Aeronautics 2014年第4期27卷 867-874页

作者： Wang Chao Qiu Jing Liu Guanjun Zhang Yong Science and Technology on Integrated Logistics Support Laboratory National University of Defense Technology College of Mechatronic Engineering and Automation National University of Defense Technology

Testability plays an important role in improving the readiness and decreasing the lifecycle cost of equipment. Testability demonstration and evaluation is of significance in measuring such testability indexes as fault detection rate（FDR） and fault isolation rate（FIR）, which is useful to the producer in mastering the testability level and improving the testability design, and helpful to the consumer in making purchase decisions. Aiming at the problems with a small sample of testability demonstration test data（TDTD） such as low evaluation confidence and inaccurate result, a testability evaluation method is proposed based on the prior information of multiple sources and Bayes theory. Firstly, the types of prior information are analyzed. The maximum entropy method is applied to the prior information with the mean and interval estimate forms on the testability index to obtain the parameters of prior probability density function（PDF）, and the empirical Bayesian method is used to get the parameters for the prior information with a success-fail form. Then, a parametrical data consistency check method is used to check the compatibility between all the sources of prior information and TDTD. For the prior information to pass the check, the prior credibility is calculated. A mixed prior distribution is formed based on the prior PDFs and the corresponding credibility. The Bayesian posterior distribution model is acquired with the mixed prior distribution and TDTD, based on which the point and interval estimates are ***, examples of a flying control system are used to verify the proposed method. The results show that the proposed method is feasible and effective.

关键词： Bayes theory Consistency check Multiple sources prior credibility prior information Testability evaluation

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Inversion of Moho Interface in Northeastern China with prior information

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Journal of Earth Science 2014年第1期25卷 146-151页

作者： Runhai Feng Ping Dong Liangshu Wang Bin Sun Yongjing Wu Changbo Li School of Earth Sciences and Engineering Nanjing University

Non-uniqueness is always, by nature, the problem we face in inversion processes, and it is caused by the phenomenon of equivalence in field, erroneous, discrete, and finite features in obser- vation and the influence of other sources. Many authors have done lots of researches in this field in order to get more reliable outcomes, and joint inversion is a thriving one where different kinds of data are combined to derive certain information simultaneously or sequentially. One of these studies is that the prior information such as the geological, drilling and seismic data will be used as con- straints, while the inversion procedure can be controlled. In this article we use a new method with the goal of better obtaining the three-dimensional density contrast interface. This prior seismic data integrated in the inversion can play a constrained role in the procedure which means that the depth of the Moho interface at the seismic location will be restricted. It thus can provide a credible result. In order to test its effect, this program is applied in a field example--derivation of Moho geometry in Northeast China.

关键词： prior information inversion Moho seismic data.

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A new learning method using prior information of neural networks

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Science in China(Series F) 2004年第6期47卷 793-814页

作者： LUeBaiquan JunichiMurata KotaroHirasawa DepartmentofAutomation ShanghaiUniversityShanghai200072China DivisionofSystemControlEngineering DepartmentofElectricalandElectronicSystemsEngineeringGraduateSchoolofInformationScienceandElectronicEngineeringKyushuUniversity6-10-1MakozakiHigashi-KuFukuoka812-8581Japan

In this paper, we present a new learning method using prior information for three-layered neural networks. Usually when neural networks are used for identification of systems, all of their weights are trained independently, without considering their interrelation of weight values. Thus the training results are not usually good. The reason for this is that each parameter has its influence on others during the learning. To overcome this problem, first, we give an exact mathematical equation that describes the relation between weight values given by a set of data conveying prior information. Then we present a new learning method that trains a part of the weights and calculates the others by using these exact mathematical equations. In almost all cases, this method keeps prior information given by a mathematical structure exactly during the learning. In addition, a learning method using prior information expressed by inequality is also presented. In any case, the degree of freedom of networks (the number of adjustable weights) is appropriately limited in order to speed up the learning and ensure small errors. Numerical computer simulation results are provided to support the present approaches.

关键词： prior information neural network learning part parameter learning exact mathematical structure.

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An image reconstruction algorithm of EIT based on pulmonary prior information

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Frontiers of Electrical and Electronic Engineering in China 2009年第2期4卷 121-126页

作者： Huaxiang WANG Li HU Jing WANG Lu LI School of Electrical Engineering and Automation Tianjin UniversityTianjin 300072China

Using a CT scan of the pulmonary tissue,a human pulmonary model is established combined with the structure property of the human lung tissue using the software *** with the conductivity contribution information of the human tissue and organ,an image reconstruction method of electrical impedance tomography based on pulmonary prior information is proposed using the conjugate gradient *** results show that the uniformity index of sensitivity distribution of the pulmonary model is 15.568,which is significantly reduced compared with 34.218 based on the round *** proposed algorithm improves the uniformity of the sensing field,the image resolution of the conductivity distribution of pulmonary tissue and the quality of the reconstruction image based on pulmonary prior information.

关键词： electrical impedance tomography(EIT) prior information pulmonary model of human image reconstruction COMSOL

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Obtaining prior information for Ultrasonic Signal Reconstruction from FRI Sparse Sampling Data

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Journal of Harbin Institute of Technology(New Series) 2018年第4期25卷 65-72页

作者： Shoupeng Song Yingjie Ni Yonghua Shao Department of Instrument Science and Engineering Jiangsu University

Finite rate of innovation sampling is a novel sub-Nyquist sampling method that can reconstruct a signal from sparse sampling *** application of this method in ultrasonic testing greatly reduces the signal sampling rate and the quantity of sampling ***,the pulse number of the signal must be known beforehand for the signal reconstruction *** accuracy of this prior information directly affects the accuracy of the estimated parameters of the signal and influences the assessment of flaws,leading to a lower defect detection *** the pulse number can be pre-given by theoretical analysis,the process is still unable to assess actual complex random orientation ***,this paper proposes a new method that uses singular value decomposition(SVD) for estimating the pulse number from sparse sampling data and avoids the shortcoming of providing the pulse number in advance for signal *** the sparse sampling data have been acquired from the ultrasonic signal,these data are transformed to discrete Fourier coefficients.A Hankel matrix is then constructed from these coefficients,and SVD is performed on the *** decomposition coefficients reserve the information of the pulse *** the decomposition coefficients generated by noise according to noise level are removed,the number of the remaining decomposition coefficients is the signal pulse *** feasibility of the proposed method was verified through simulation *** applicability was tested in ultrasonic experiments by using sample flawed *** from simulations and real experiments demonstrated the efficiency of this method.

关键词： FRI ultrasonic signal sparse sampling signal reconstruction prior information

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Broadband constrained inversion of common offset GPR data using prior information from well log

Broadband constrained inversion of common offset GPR data us...

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信号处理在地球物理——浙江省信号处理学会2018年学术年会

作者： Yu Liu Zhanjie Shi Bangbing Wang Tianxiang Yu Jie Liu School of Earth Sciences Zhejiang University Institute of Culture and Heritage Zhejiang University

Quantitative amplitude information of ground penetrating radar(GPR) spawns another generation of data analysis and interpretation tools based on inversion method to image subsurface material *** the frequently used common offset GPR surveys,impedance inversion provides an effective way for estimating parameters of ***,previous studies are limited to band-limited impedance inversion,where errors would accumulate with computing the *** prior information from well log to construct a dependable starting model,we present a novel scheme inverting common offset GPR amplitudes to subsurface properties by means of broadband constrained *** introducing the theoretical background,we show a numerical test which employs a realistic and complex stochastic *** broadband constrained inversion result corresponds well with true model while it also exhibits advantages over band-limited impedance inversion result on *** is shown that broadband constrained inversion of common offset GPR data is a reliable method in near surface geophysics investigations.

关键词： Ground penetrating radar prior information Inversion Electromagnetic impedance Permittivity Stochastic media

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CT local reconstruction of solid rocket motor based on PI-POCS-TVM

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航空动力学报 2017年第2期32卷 470-476页

作者： LU Hong-yi CHEN Qing-gui ZHU Min LI Peng ZHAO Ru-yan WANG Bin Airborne Vehicle Engineering Department Naval Aeronautical and Astronautical University Yantai Shandong 264001 China Qingdao Branch Naval Aeronautical and Astronautical University Qingdao Shandong 266041 China No. 7 Department Naval Aeronautical and Astronautical University Yantai Shanctong 264001 China

In order to test the defects of solid rocket motor(SRM)accurately and efficiently,the computed tomography(CT)inspection scheme for SRM's defects was investigated and a CT local reconstruction algorithm called prior information-projection onto convex sets-total variation minimization(PI-POCS-TVM)was *** SRM was first inspected by industrial CT(ICT)to generate a low-resolution SRM image used as the prior information,then high-resolution local inspection was carried out for SRM's *** validate the effectiveness of the CT inspection scheme for SRM's defects,one SRM was inspected by a narrow fan beam ICT *** back projection(FBP)algorithm,POCS,POCS-TVM and PI-POCS-TVM algorithms were applied to reconstruct CT *** performance of these algorithms was also *** demonstrated the effectiveness of the CT inspection scheme for SRM's ***,the PI-POCS-TVM algorithm has better local reconstruction image quality than the other three algorithms,showing great significance for accurate measurement of SRM's defects.

关键词： interior tomography exterior tomography compressed sensing prior information projection onto convex sets-total variation minimization(POCS-TVM) solid rocket motor

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Individual Word Length Patterns for Fractional Factorial(Split-Plot)Designs

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Journal of Systems Science & Complexity 2023年第5期36卷 2082-2099页

作者： HAN Xiaoxue CHEN Jianbin YANG Jianfeng LIU Minqian School of Statistics and Data Science Qufu Normal UniversityQufu 273165China School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China School of Statistics and Data Science LPMC&KLMDASRNankai UniversityTianjin 300071China

Fractional factorial(FF)designs are commonly used for factorial experiments in many *** some prior knowledge has shown that some factors are more likely to be significant than others,Li,et al.(2015)proposed a new pattern,called the individual word length pattern(IWLP),which,defined on a column of the design matrix,measures the aliasing of the effect assigned to this column and effects involving other *** this paper,the authors first investigate the relationships between the IWLP and other popular criteria for regular FF *** we know,fractional factorial split-plot(FFSP)designs are important both in theory and *** another contribution of this paper is extending the IWLP criterion from FF designs to FFSP *** authors propose the IWLP of a factor from the whole-plot(WP),or sub-plot(SP),denoted by the I_w WLP and Is WLP respectively,in the FFSP *** authors further propose combined word length patterns C_(w) WLP and Cs WLP,in order to select good designs for different *** new criteria C_(w) WLP and Cs WLP apply to the situations that the potential important factors are in WP or SP,*** examples are presented to illustrate the selected designs based on the criteria established here.

关键词： Effect hierarchy fractional factorial split-plot prior information regular design

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The role of prior in image based 3D modeling： a survey

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Frontiers of Computer Science 2017年第2期11卷 175-191页

作者： Hao ZHU Yongming NIE Tao YUE Xun CAO Lab for Computational Imaging Technology and Engineering School of Electronic Science and Engineering Nanjing University Nanjing 210023 China

The prior knowledge is the significant supple- ment to image-based 3D modeling algorithms for refining the fragile consistency-based stereo. In this paper, we review the image-based 3D modeling problem according to prior cate- gories, i.e., classical priors and specific priors. The classical priors including smoothness, silhouette and illumination are well studied for improving the accuracy and robustness of the 3D reconstruction. In recent years, various specific priors which take advantage of Manhattan rule, geometry template and trained category features have been proposed to enhance the modeling performance. The advantages and limitations of both kinds of priors are discussed and evaluated in the paper. Finally, we discuss the trend and challenges of the prior studies in the future.

关键词： prior information consistency-based stereo,smoothness illumination silhouette specific prior

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Theory of Compressive Sensing via l1-Minimization:a Non-RIP Analysis and Extensions

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Journal of the Operations Research Society of China 2013年第1期1卷 79-105页

作者： Yin Zhang Department of Computational and Applied Mathematics Rice University6100 MainHoustonTX 77005USA

Compressive sensing(CS)is an emerging methodology in computational signal processing that has recently attracted intensive research *** present,the basic CS theory includes recoverability and stability:the former quantifies the central fact that a sparse signal of length n can be exactly recovered from far fewer than n measurements via l1-minimization or other recovery techniques,while the latter specifies the stability of a recovery technique in the presence of measurement errors and inexact *** far,most analyses in CS rely heavily on the Restricted Isometry Property(RIP)for *** this paper,we present an alternative,non-RIP analysis for CS via *** purpose is three-fold:(a)to introduce an elementary and RIP-free treatment of the basic CS theory;(b)to extend the current recoverability and stability results so that prior knowledge can be utilized to enhance recovery via l1-minimization;and(c)to substantiate a property called uniform recoverability of l1-minimization;that is,for almost all random measurement matrices recoverability is asymptotically *** the aid of two classic results,the non-RIP approach enables us to quickly derive from scratch all basic results for the extended theory.

关键词： Compressive sensing l1-Minimization Non-RIP analysis Recoverability and stability prior information Uniform recoverability

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