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关键词： 控制科学与技术   传感器技术   反隐身   多传感器组网   部分可观察马尔可夫决策过程   信念状态   任务规划  

摘要： 针对反隐身作战需求,提出多被动传感器组网协同战术。为提升反隐身探测效能,引入部分可观察马尔可夫决策过程(POMDP)理论,分析了POMDP任务规划要素,建立起多被动传感器组网协同反隐身探测任务规划POMDP模型。建立了多被动传感器协同控制系统结构,提出了基于无迹卡尔曼滤波(UKF)的信念状态更新方法和基于蒙特卡洛Rollout采样(MCRS)的Q值估计方法,并设计了CCSP基本策略。仿真结果表明,所建立的模型能够实现多被动传感器的高效管理调度,能够控制多被动传感器对隐身目标进行有效探测跟踪,即模型有效性得到了验证。

关键词： 意法半导体   互动功能   环境噪音   音频   智能   装置   传感器技术   自动选择  

摘要： 意法半导体（STMicroelectronics，简称ST）宣布其产品获Prizm^TM公司智能音频装置（smartaudiodevice）选用。Prim^TM智能音频装置能够根据室内人数以及每个人的音乐品味与欣赏音乐的习惯，甚至是当天的时间和环境噪音大小自动选择播放的歌曲。意法半导体先进的微控制器与传感器技术帮助Prizm实现了智能音频及触控互动功能。

关键词： 分布式光纤传感器   井下数据采集   新技术   传输方式   传感器技术   贝尔公司   动态监测   挠性管  

摘要： 分布式光纤（DFO，Distributed Fiber-optic）传感器技术已经广泛应用于井下数据采集。兹贝尔公司开发的Z系统（Z-System）传输方式为挠性管传输，无需使用井下爬行器，能提供井下高质量数据采集，实现井下储层的动态监测。

关键词： 多功能传感器   传感器技术   登陆器   波兰   菲   应用   欧洲航天局   探测计划  

摘要： 2014年11月12日,欧洲航天局罗塞塔彗星探测计划下的菲莱登陆器（Philae）登上楚留莫夫-格拉希门克彗星,成为有史以来第一个字彗星上成功受控着陆的探测器。菲莱登陆器上使用的地表及地下多功能传感器（MUPUS）由波兰科学院空间研究中心制造,采用了华沙理工大学提供的技术。MUPUS是一个复杂的地质穿透器,它的任务是穿透彗星地表,测量彗星表层和表层以下的温度及其导热性。

关键词： Acoustic emission sensor   bearing   fault diagnosis  

摘要： The diagnosis of bearing health by quantifying acoustic emission data has been an area of interest for recent years due to the numerous advantages over vibration-based techniques. However, most acoustic emission-based methodologies to date are data-driven technologies. This research takes a novel approach combining a heterodyne-based frequency reduction technique, time synchronous resampling, and spectral averaging to process acoustic emission signals and extract condition indicators for bearing fault diagnosis. The heterodyne technique allows the acoustic emission signal frequency to be shifted from several megahertz to less than 50kHz, which is comparable to that of vibration-based techniques. Then, the digitized signal is band-pass filtered to retain the information associated with the bearing defects. Finally, the tachometer signal is used to time synchronously resample the acoustic emission data, allowing the computation of a spectral average which in turn enables the extraction and evaluation of condition indicators for bearing fault diagnosis. The presented technique is validated using the acoustic emission signals of seeded fault steel bearings on a bearing test rig. The result is an effective acoustic emission-based approach validated to diagnose all four fault types: inner race, outer race, ball, and cage.

关键词： BREAST exams   MAMMOGRAMS   BREAST self-examination   BREAST imaging centers   MEDICAL self-examination  

摘要： Sensor Technology in Assessments of Clinical Skill (Correspondence, N Engl J Med2015 ; 372 : 784 - 786). In the full author list published with the letter at ***, Dr. Pugh should have been listed as the final author, rather than as the third author. The letter is correct at *** PDF Print Download Citation E-MailSave Article Alert Submit a LetterReprints Permissions Share/BookmarkRelated ArticlesCorrespondenceSensor Technology in Assessments of Clinical SkillFebruary 19, 2015 | S. Laufer and OthersMore InOtherMarch 19, 2015Trends Most Viewed (Last Week)Original Article Trial of Everolimus-Eluting Stents or Bypass Surgery for Coronary Disease[40,595 views] March 26, 2015 | S. Park and Others Images in Clinical Medicine Nasal Myiasis[38,077 views] March 19, 2015 | M.A. Baptista Images in Clinical Medicine Spina Ventosa[34,565 views] March 26, 2015 | R. Baeza-Trinidad and J.A.O. Revuelta More TrendsContent:HomeCurrent IssueArticlesIssue IndexSpecialties & TopicsMultimedia & ImagesArchive 1812-1989 Information For:AuthorsReviewersSubscribersInstitutionsMediaAdvertisers Services:SubscribeRenew Pay BillActivate SubscriptionCreate or Manage AccountAlertsRSS & PodcastsSubmit a ManuscriptMobile Resources:Physician JobsReprintsPermissionsMedical MeetingsConventionsFAQs NEJM Knowledge+NEJM Journal Watch Help Contact Us NEJM:AboutProduct InformationEditors & Publishers 200th AnniversaryTerms of UsePrivacy PolicyCopyrightAdvertising Policies NEJM Group CME:Weekly CME ProgramBrowse Weekly Exams Your CME ActivityPurchase ExamsReview CME Program Follow us Article Category Research Reviews Clinical Cases Perspective Commentary Other Browse all ArticlesMultimedia Videos in Clinical Medicine Images in Clinical Medicine Interactive Medical Cases Quick Take Videos Weekly Audio Summaries Audio Interviews Browse all multimediaThis Week Last Week Browse full index Selected Specialties Cardiology Endocrinology Gastroenterology Genetics Hematology/Oncolog

关键词： AIR pollution control   SOOT   CARBONACEOUS aerosols   ENVIRONMENTAL monitoring   AIR pollution monitoring -- Equipment & supplies  

摘要： Novel technologies, such as smartphones and small personal continuous air pollution sensors, can now facilitate better personal estimates of air pollution in relation to location. Such information can provide us with a better understanding about whether and how personal exposures relate to residential air pollution estimates, which are normally used in epidemiological studies. The aims of this study were to examine （1） the variability in personal air pollution levels during the day and （2） the relationship between modeled home and school estimates and continuously measured personal air pollution exposure levels in different microenvironments （e.g., home, school, and commute）. We focused on black carbon as an indicator of traffic-related air pollution. We recruited 54 school children （aged 7–11） from 29 different schools around Barcelona as part of the BREATHE study, an epidemiological study of the relation between air pollution and brain development. For 2 typical week days during 2012–2013, the children were given a smartphone with CalFit software to obtain information on their location and physical activity level and a small sensor, the micro-aethalometer model AE51, to measure their black carbon levels simultaneously and continuously. We estimated their home and school exposure to PM_2.5 filter absorbance, which is well-correlated with black carbon, using a temporally adjusted PM_2.5 absorbance land use regression （LUR） model. We found considerable variation in the black carbon levels during the day, with the highest levels measured during commuting periods （geometric mean = 2.8 μg/m³） and the lowest levels at home （geometric mean = 1.3 μg/m³）. Hourly temporally adjusted LUR model estimates for the home and school showed moderate to good correlation with measured personal black carbon levels at home and school （r = 0.59 and 0.68, respectively） and lower correlation with commuting trips （r = 0.32 and 0.21, respectively）. T

关键词： 高分辨率遥感影像   监督分类   建模框架   模型   卫星平台   立体观测   传感器技术   航空飞机  

摘要： 1研究背景与意义 随着卫星与传感器技术的迅速发展，高（空间）分辨率遥感影像的可获取性日益增强。一系列的在轨高分辨率遥感卫星平台连同低空平台的轻小型航空飞机和无人机所构建的立体观测系统，为全天候、全天时精确地观测全球地表覆盖提供了可能。

关键词： 自动驾驶技术   法律法规   车辆   汽车电子技术   美国   交通管理部门   道路交通   传感器技术  

摘要： 随着汽车电子技术、传感器技术、计算机技术、车联网技术等技术的发展，自动驾驶技术的研发和应用越来越为人所关注，自动驾驶车辆，离我们的生活也并不遥远!为此，道路交通管理部门有必要及时跟踪了解国外自动驾驶车辆制度修订相关情况，分析其对我国的适用性，适时提出修订我国道路交通法律法规相关规定的意见和建议。

关键词： 前置放大器   产品线   传感器技术   紧凑型   北京   压电   美国   汽车发动机  

摘要： PCB扩展其传声器前置放大器产品线，开发了新型1／2英寸超短尺寸前置放大器。426A13适用于传统传声器系统不适用或者空间受限的场合诸如汽车发动机下面或者一个腔体里面进行的声学测试。