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Fully distributed variational Bayesian non-linear filter with unknown measurement noise in sensor networks

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Science China(Information Sciences) 2020年第11期63卷 24-37页

作者： Yu LIU Jun LIU Congan XU Gang LI you he Research Institute of Information Fusion Naval Aviation University Department of Electronic Engineering Tsinghua University

In practical applications, the measurement noise statistics is usually unknown or may change over time. However, most existing distributed filtering algorithms for sensor networks are constructed based on exact knowledge of measurement noise statistics. Therefore, under situations with measurement uncertainty, the existing algorithms may result in deteriorated performance. To solve such problems, a distributed adaptive cubature information filter based on variational Bayesian(VB-DACIF) is proposed here. Firstly,the predicted estimates of interest from inclusive neighbours are fused by minimizing the weighted KullbackLeibler average, in which the cubature rule is utilized to tackle system nonlinearity. Then, the free form variational Bayesian approximation is applied to recursively update both the local estimate and the precision matrices of sensing nodes. Finally, the posterior Cram′er-Rao lower bound is exploited to evaluate performance of the proposed VB-DACIF. Simulation results with a maneuvering target tracking scenario validates the feasibility and superiority of the proposed VB-DACIF.

关键词： sensor networks distributed state estimation cubature Kalman filter variational Bayesian inference Kullback-Leibler divergence

Endocytosis by target cells:an essential means for perforin-and granzyme-mediated killing

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Cellular & Molecular Immunology 2012年第1期9卷 5-6页

作者： Claire Gordy you-Wen he Department of Immunology Duke University Medical CenterDurhamNCUSA

D espite the critical role of cell-mediated immunity in defense against intracellular pathogens,cancer immunosurveillance and development of autoimmunity,the precise mechanisms governing the killing of target cells by cytotoxic T cells(CTLs)and natural killer(NK)cells have remained poorly *** a study published in Nature Immunology,Thiery and colleagues have for the first time visualized the movement of the cytotoxic granule proteins perforin and granzymes from the killer cell to the target cell,challenging the textbook model of granulemediated cytotoxicity and providing direct evidence for a multistep endocytosis-mediated mechanism for the entry of granzymes to the target cell’s cytoplasm.

关键词： mediated immunity killer

New optimal algorithm of data association for multi-passive-sensor location system

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Science in China(Series F) 2007年第4期50卷 600-608页

作者： ZHOU Li he you ZHANG WeiHua School of Management Ludong University Yantai 264025 China Research Institute of Information Fusion Naval Aeronautical Engineering Institute Yantai 264001 China Property and Logistic Management Ludong University Yantai 264025 China

In dense target and false detection scenario of four time difference of arrival （TDOA） for multi-passive-sensor location system, the global optimal data association algorithm has to be adopted. In view of the heavy calculation burden of the traditional optimal assignment algorithm, this paper proposes a new global optimal assignment algorithm and a 2-stage association algorithm based on a statistic test. Compared with the traditional optimal algorithm, the new optimal algorithm avoids the complicated operations for finding the target position before we calculate association cost; hence, much of the procedure time is saved. In the 2-stage association algorithm, a large number of false location points are eliminated from candidate associations in advance. Therefore, the operation is further decreased, and the correct data association probability is improved in varying degrees. Both the complexity analyses and simulation results can verify the effectiveness of the new algorithms.

关键词： optimal assignment algorithm data association 2-stage association algorithm multi-passive-sensor location system distance difference of arrival (DDOA)

Fast Algorithm for Maneuvering Target Detection in SAR Imagery Based on Gridding and Fusion of Texture Features

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Geo-Spatial Information Science 2011年第3期14卷 169-176页

作者： YUAN Zhan he you CAI Fuqing Research Institute of Information Fusion Technology Naval Aeronautical and Astronautical University 128 Erma Road Yantai264001 China

Designing detection algorithms with high efficiency for Synthetic Aperture Radar(SAR) imagery is essential for the operator SAR Automatic Target Recognition(ATR) *** work abandons the detection strategy of visiting every pixel in SAR imagery as done in many traditional detection algorithms,and introduces the gridding and fusion idea of different texture fea-tures to realize fast target *** first grids the original SAR imagery,yielding a set of grids to be classified into clutter grids and target grids,and then calculates the texture features in each *** fusing the calculation results,the target grids containing potential maneuvering targets are *** dual threshold segmentation technique is imposed on target grids to obtain the regions of *** fused texture features,including local statistics features and Gray-Level Co-occurrence Matrix(GLCM),are *** efficiency and superiority of our proposed algorithm were tested and verified by comparing with existing fast de-tection algorithms using real SAR *** results obtained from the experiments indicate the promising practical application val-ue of our study.

关键词： synthetic aperture radar imagery target detection texture feature gridding gray-level co-occurrence matrix fusion

Gut perforation after orthotopic liver transplantation in adults

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World Journal of Gastroenterology 2007年第14期13卷 2125-2128页

作者： Jun Xiong Shen you Xiao-Shun he Organ Transplantation Center 1^st Affiliated Hospital Sun Yat-Sen University Guangzhou 510080 Guangdong Province China

AIM： To describe cases of gut perforation after orthotopic liver transplantation.METHODS： Data were colleted from our center database and medical records. Six of 187 patients （3.2%）who underwent orthotopic liver transplantation from January to December 2005 developed gut *** patients were male with an average age of 46 *** piggyback liver transplantation was performed at the Organ Transplantation Center, First Affiliated Hospital, Sun Yat-Sen ***： Previous operation, steroid therapy, and prolonged portal venous cross clamp time, poor nutritional status and iatrogenic injury were found to be its ecological factors. The patients with gut perforation were found to have fever, increased leukocytes, mild abdominal pain and tenderness. The median portal venous clamp time was 63 min （range 45-72 min）,median cold ischaemia time was 11.3 h （range 7-15 h）.Median intraoperative blood loss was 500 mL （range 100-1200 mL） and median operation time was 8.8 h （range 6-12 h）. None of the six patients developed acute cellular rejection. White cell count was above 18 × 10^9/L in five patients （neutrophilic leukocytes were above 90%） and 1.5 × 10^9/L in one patient. Bacterial culture in drainage liquid revealed enterococci in five patients. Of the 6 patients undergoing orthotopic liver transplantation, 3 survived and 3 died after modified piggyback liver transplantation.CONCLUSION： Gut perforation occurs after orthotopic liver transplantation in adults. A careful and minimal dissection during OLT, longer retention of the stomach tube, and reducing the portal clamp time and steroid dose should be taken into consideration. If gut perforation is not prevented, then early diagnosis,preferably through detection of enterococci may ensure better survival.

关键词： Orthotopic liver transplantation Gut perforation Enterococcus faecalis

基于数据挖掘的发电厂烟气循环排放自动监测系统设计

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自动化技术与应用 2024年第3期43卷 57-61页

作者：杨林徐有和张伟内蒙古京能双欣发电有限公司内蒙古鄂尔多斯016014

为解决现有系统烟气参数监测误差大、监测范围小等问题,基于数据挖掘设计发电厂烟气循环排放自动监测系统。从软硬件两方面优化系统,先改装烟气监测仪、烟气采样探头和系统控制器,根据数据挖掘技术的应用要求调整数据处理器的内部结构... 详细信息

为解决现有系统烟气参数监测误差大、监测范围小等问题,基于数据挖掘设计发电厂烟气循环排放自动监测系统。从软硬件两方面优化系统,先改装烟气监测仪、烟气采样探头和系统控制器,根据数据挖掘技术的应用要求调整数据处理器的内部结构。然后布设烟气监测点,利用数据挖掘技术自动获取烟气循环排放数据。最后计算排放量、浓度、流速等监测参数,通过实时监测数据的更新输出,实现系统的自动监测功能。系统测试实验得出:优化设计系统的烟气浓度、温度和流速的监测误差均较低。

关键词：数据挖掘发电厂烟气循环排放自动监测系统

Measuring Conflict Functions in Generalized Power Space

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Chinese Journal of Aeronautics 2011年第1期24卷 65-73页

作者： HU Lifang GUAN Xin DENG Yong HAN Deqiang he you Research Institute of Information Fusion Naval Aeronautical and Astronautical University Yantai 264001 China Sche Institute of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China School of Electronics and Information Technology Shanghai Jiaotong University Shanghai 200240 China Institute of Integrated Automation Xi 'an Jiaotong University Xi 'an 710049 China

One of the most important open issues is that the classical conflict coefficient in D-S evidence theory （DST） cannot correctly determine the conflict degree between two pieces of evidence. This drawback greatly limits the use of DST in real application systems. Early researches mainly focused on the improvement of Dempster’s rule of combination （DRC）. However, the current research shows it is very important to define new conflict coefficients to determine the conflict degree between two or more pieces of evidence. The evidential sources of information are considered in this work and the definition of a conflict measure function （CMF） is proposed for selecting some useful CMFs in the next fusion work when sources are available at each instant. Firstly, the definition and theorems of CMF are put forward. Secondly, some typical CMFs are extended and then new CMFs are put forward. Finally, experiments illustrate that the CMF based on Jousselme and its similar ones are the best suited ones.

关键词： D-S evidence theory conflict evidence generalized power space information fusion uncertainty

High resolution radar target adaptive detector and performance assessment

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Journal of Systems Engineering and Electronics 2011年第2期22卷 212-218页

作者： Tao Jian you he Feng Su Changwen Qu Dianfa Ping Research Institute of Information Fusion Naval Aeronautical and Astronautical University Yantai 264001 P. R. China

The high resolution radar target detection is addressed in the non-Gaussian clutter. An adaptive detector is derived for range-spread target based on a novel covariance matrix estimator. It is proved that the new detector is constant false alarm rate （CFAR） to both of the clutter covariance matrix structure and power level theoretically for match cases. The simulation results show that the new detector is almost CFAR for mismatch cases, and it outperforms the existing adaptive detector based on the sample covariance matrix. It also shows that the detection performance improves, as the number of pulses, the number of secondary data or the clutter spike increases. In addition, the derived detector is robust to different subsets, estimated clutter group sizes and correlations of clutter. Importantly, the number of iterations for practical application is just one.

关键词： non-Gaussian clutter adaptive detection range-spread target performance assessment.

New probabilistic transformation of imprecise belief structure

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Journal of Systems Engineering and Electronics 2011年第5期22卷 721-729页

作者： Lifang Hu you he Xin Guan Deqiang Han Yong Deng Research Institute of Information Fusion Naval Aeronautical and Astronautical University Yantai 264001 E R. China Navy Armament Academy Beijing 102249 E R. China College of Electronic Science and Engineering National University of Defense Technology Changsha 410073 E R. China Institute of Integrated Automation Xi＇an Jiaotong University Xi＇an 710049 E R. China School of Electronics and Information Technology Shanghai Jiaotong University Shanghai 200240 E R. China

The case when the source of information provides precise belief function/mass, within the generalized power space, has been studied by many people. However, in many decision situations, the precise belief structure is not always available. In this case, an interval-valued belief degree rather than a precise one may be provided. So, the probabilistic transformation of imprecise belief function/mass in the generalized power space including Dezert-Smarandache （DSm） model from scalar transformation to sub-unitary interval transformation and, more generally, to any set of sub-unitary interval transformation is provided. Different from the existing probabilistic transformation algorithms that redistribute an ignorance mass to the singletons involved in that ignorance pro- portionally with respect to the precise belief function or probability function of singleton, the new algorithm provides an optimization idea to transform any type of imprecise belief assignment which may be represented by the union of several sub-unitary （half-） open intervals, （half-） closed intervals and/or sets of points belonging to [0,1]. Numerical examples are provided to illustrate the detailed implementation process of the new probabilistic transformation approach as well as its validity and wide applicability.

关键词： pignistic probability transformation generalized power space interval value information fusion uncertainty.