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武汉大学学报（理学版） 2002年第5期48卷 549-552页

作者：田俊忠胡迪鹤西北第二民族学院信息与计算科学系宁夏银川750021 武汉大学数学与统计学院湖北武汉430072

研究了连续时间的可数状态的随机准转概阵的a .s.样本连续性及可微性 ,进而研究了随机环境Q过程的存在性并构造出最小的随机环境Q过程。

关键词：随机准转概阵随机准转强阵随机环境Q过程 a.s.样本连续性 a.s.样本可微性马氏过程

Matrix-Geometric Solution of a Heterogeneous Two-Server M/（PH,M）/2 Queueing System with Server Breakdowns

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Matrix-Geometric Solution of a Heterogeneous Two-Server M/（...

久坐与社区老年人下肢肌力:跌倒恐惧与年龄的中介和调节作用

2010 Chinese Control and Decision Conference

作者： Dequan Yue~1,Ling Wang~1,Tingting Xu~1,Haiying Li~1 1.department of statistics,College of Science,Yanshan university,Qinhuangdao 066004,China

＜正＞In this paper,we study a repairable queueing system with two different servers,where Server 1 is perfectly reliable and Server 2 is subject to *** service times of two servers are assumed to follow phase type（PH） distribution and exponential distribution,*** establishing the quasi-birth-and-death（QBD） process of the system states,we first derive the equilibrium condition of the system,and then obtain the matrix-geometric solution for the steady-state probability vectors of the ***,numerical results are presented.

关键词： Queueing system Breakdowns Matrix-geometric solution PH distribution Mean system size

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中国组织工程研究 2025年第17期29卷 3566-3571页

作者：洪金涛王晶晶李岩松王晨弭守玲上海体育科学研究所(上海市反兴奋剂中心) 上海市200030 青岛大学体育学院山东省青岛市266071 复旦大学附属中山医院心内科上海市心血管病研究所上海市200032 国家放射与治疗临床医学研究中心上海市200032 心脏病全国重点实验室上海市200032 国家卫生健康委缺血性心脏病重点实验室上海市200032 中国医学科学院病毒性心脏病重点实验室上海市200032

背景:人体老龄化进程中,下肢肌肉力量会随着年龄的增长呈现显著的生理性下降,久坐、跌倒恐惧、年龄与下肢肌力之间可能存在一定关联,但它们之间的影响路径与效应关系尚不明确。目的:探究社区老年人久坐和下肢肌肉力量之间的关系,并探讨... 详细信息

背景:人体老龄化进程中,下肢肌肉力量会随着年龄的增长呈现显著的生理性下降,久坐、跌倒恐惧、年龄与下肢肌力之间可能存在一定关联,但它们之间的影响路径与效应关系尚不明确。目的:探究社区老年人久坐和下肢肌肉力量之间的关系,并探讨跌倒恐惧和年龄在上述两者关系中的作用。方法:共招募331名60岁及以上的上海市社区老年人。采用问卷调查法收集基本信息、人口学资料等;采用国际身体活动问卷-短卷评估久坐时间,采用30 s坐站测试测量下肢肌力,采用中文版国际跌倒效能量表测评跌倒恐惧。对数据进行描述统计、相关分析、基于回归的路径分析和中介效应检验。结果与结论:最终以318名老年人[78.9%为女性,平均年龄(67.8±5.5)岁]的有效数据纳入分析,其中久坐时间≥3 h的185名,25,P2,P293,P<0.001)。③跌倒恐惧在久坐和下肢肌力之间起中介作用(β=-0.053,95%CI:-0.100至-0.018)。④久坐对跌倒恐惧的预测效应具有统计学意义(β=0.164,P<0.01),这说明年龄调节了久坐对跌倒恐惧的影响。

关键词：老年群体老龄化肌肉萎缩肌肉力量久坐跌倒恐惧中介效应调节作用

A New Algorithm of Track Initiation for Multiple Targets and Performance Analysis

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Decoding defect statistics from diffractograms via machine learning

2010 2nd International Conference on Multimedia and Computational Intelligence (ICMCI 2010)

作者： Sheng Liu1 2 and Guangshan Lu1 department of Automation 1. Nanjing university of Aeronautics and Astronautics 2. Luoyang research institute of electro-optical equipment Luo Yang Henan Province China Yingying Wei Shaowei Chen and Xinjian Shi department of Electronics and Information Northwestern Polytechnical university Xi’an Shaanxi Province China

After researching track initiation algorithm based on the modified logic, a new high efficient algorithm is proposed. A potential track is formed using location information. In follow scanning period a elliptic associated region is calculated using state Estimation, at the same time a limitation condition is added to exclude the returns which may form V-shape tracks. The performance index is deduced by statistics methods. Simulation results show the new algorithm has the better performance than the modified logic algorithm. The track detection probability is up to 0.25 in the intensive clutters. And false track probability drop down a lot.

关键词： track initiation modified logic track detection probability false track probability

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npj Computational Materials 2021年第1期7卷 601-609页

作者： Cody Kunka Apaar Shanker Elton Y.Chen Surya R.Kalidindi Rémi Dingreville Center for Integrated Nanotechnologies Sandia National LaboratoriesAlbuquerqueNMUSA.2Georgia Institute of TechnologyAtlantaGAUSA

Diffraction techniques can powerfully and nondestructively probe materials while maintaining high resolution in both space and ***,these characterizations have been limited and sometimes even erroneous due to the difficulty of decoding the desired material information from features of the ***,these features are identified non-comprehensively via human intuition,so the resulting models can only predict a subset of the available structural *** the present work we show(i)how to compute machine-identified features that fully summarize a diffractogram and(ii)how to employ machine learning to reliably connect these features to an expanded set of structural *** exemplify this framework,we assessed virtual electron diffractograms generated from atomistic simulations of irradiated *** based on machine-identified features rather than human-identified features,our machine-learning model not only predicted one-point statistics(***)but also a two-point statistic(*** distribution)of the defect ***,this work demonstrates that machine-learning models that input machine-identified features significantly advance the state of the art for accurately and robustly decoding diffractograms.

关键词： diff learning defect

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基于概率统计的韵律短语分析

计算机工程与应用 2001年第3期37卷 10-11,34页

作者：谌卫军林福宗李建民张钹清华大学计算机科学与技术系

韵律短语分析是文语转换（Ｔｅｘｔ－ｔｏ－Ｓｐｅｅｃｈ）系统的重要组成部分。文章实现了一个基于概率统计的韵律短语分析方法。它首先构造了一个带有韵律短语间隔标记和词语ＰＯＳ信息的样本库，然后用它来训练和测试一个二元组模型... 详细信息

韵律短语分析是文语转换（Ｔｅｘｔ－ｔｏ－Ｓｐｅｅｃｈ）系统的重要组成部分。文章实现了一个基于概率统计的韵律短语分析方法。它首先构造了一个带有韵律短语间隔标记和词语ＰＯＳ信息的样本库，然后用它来训练和测试一个二元组模型，并针对出现的各种问题，提出了四种改进的思路。

关键词：文语转换韵律短语概率模型概率统计语音识别

Self-tuning Measurement Fusion Kalman Filter with Correlated Measurement Noises and Its convergence

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Detecting Latent Prints on Stone and Other Difficult Porous Surfaces via Indanedione/Zinc Chloride and Laser

第二十七届中国控制会议

作者： Gao Yuan,Deng Zili department of Automation,Heilongjiang university,Harbin 150080,P.R.China

For the multisensor system with unknown noise statistics and correlated measurement noises,based on the solution of the matrix equations for correlation function,the on-line estimators of the noise variances and cross-covariances are obtained. Further,a self-tuning weighted measurement fusion Kalman filter is *** on the stability of the dynamic error system and the concept of the convergence in a realization,it is strictly proved that the proposed self-tuning filter convergences to the steady-state optimal Kalman filter in a realization or with probability one,so that it has asymptotic global optimality. Compared with the centralized self-tuning Kalman filter,it can reduce the computational burden,and is suitable for real time applications.A simulation example for a target tracking system with 3-sensor shows its effectiveness.

关键词： Multisensor measurement fusion Self-tuning Kalman filter Convergence in a realization Correlation method

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Journal of Forensic Science and Medicine 2016年第4期2卷 203-207页

作者： Shiquan LIU Zhongliang mi Jian Wu Brian Dalrymple Forensic Science department Institute of Evidence Law and Forensic ScienceChina University of Political Science and LawBeijing1Shanghai Police DepartmentShanghai Key Laboratory of Criminal Scene EvidenceShanghai probability and statistics department College of ScienceNortheastern UniversityShenyangChina Forensic Identification department Ontario Provincial PoliceCanada

Lasers and alternate light sources have been recognized as effective tools for latent print detection for over three *** often increases friction ridge contrast to reveal impressions otherwise ***/zinc chloride excited by a forensic light source is widely recognized as an effective process for developing latent prints on porous *** study was designed to evaluate the use of a combination of luminescence excitation and indanedione with zinc chloride to detect latent prints on stones,bricks,and similar difficult porous *** wavelengths evaluated included 400 nm(violet),447 nm(blue),532 nm(green),and 645 nm(red).Latent prints were deposited on a variety of porous surfaces including bricks,cement stones,wood,and cotton fabric,all commonly encountered at crime scenes in *** surfaces were examined using white light(light‑emitting diode flashlight)and laser light sources separately,both before and after treatment with indanedione/zinc *** goal of this study was to evaluate various light sources for their effectiveness in detecting impressions developed by indanedione/zinc chloride on difficult porous *** indicated that latent prints on some brick and cement stone surfaces may be effectively detected using 532 nm laser excitation after indanedione/zinc chloride processing.

关键词： Indanedione laser latent print porous surface

Influence of Inclusion on Crack Initiation in Wheel Rim

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Journal of Iron and Steel Research International 2011年第1期18卷 49-54页

作者： mi Guo fa NAN Hong yan LIU Yan-lei ZHANG Bin ZHANG Hong SONG Guo xiang School of Materials Science and Engineering Henan Polytechnic University Jiaozuo 454003 Henan China Datong ABC Casting Co Ltd Technology and Quality Department Datong 037038 Shanxi China Metals and Chemistry Institute China Academy of Railway Sciences Beijing 100081 China

Speed increase and heavy haul of the railway freight car are the effective measures to raise the transport ability of railway, and they have been the new trend for railway freight car development. The increase of speed and axle load will lead to the increase of wheel rail contact stress, which will make a great change of stress distribution in the whole wheel rim. Goodier equation was employed to analyze the stress state around inclusion and cavity. In the operation of wheel-rail contact stress, stress concentration occurred in the pole of Al2O3 spherical inclusion, while it appeared on the equator of cavity. The critical inclusion sizes of 250 kN axle load freight car wheel at different velocities, a certain distance away from the tread, were calculated by Murakami equation. Comparing the inclusion in cast steel wheel with that in rolled steel wheel, it is found that the inclusion in cast steel wheel has much more excellent crack resistance than that in rolled steel wheel. In the meantime, in order to reduce the probability of rim crack, some suggestions were put forward.

关键词： heavy haul contact stress critical inclusion size rim crack

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交通流微观模型与宏观模型的统一

同济大学学报（自然科学版） 1997年第1期25卷 46-49页

作者：陈建阳同济大学道路与交通工程系上海200092

以改进的微观跟车模型为基础，利用交通流稳态特性和概率统计方法得出了交通流宏观统计模型．首次在严格理论意义上使交通流微观模型和宏观统计模型得到了统一，所得的宏观统计模型在许多方面优于传统的经验回归模型．

关键词：交通流跟车模型微观宏观