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关键词： Distributed parameter systems (DPSs)   mobile sensor networks   parameter identification.  

摘要： The problem of online parameter identification for spatially distributed systems using a mobile sensor network is investigated in this brief. Inspired by the passive identifier developed for boundary control of partial differential equations (PDEs) using a static sensor network, we propose a distributed online passive identifier that is able to estimate the unknown diffusion coefficient of the advection-diffusion PDE using data collected by a mobile sensor network moving in the field. To enable the online passive identifier, we develop a distributed cooperative Kalman filter run by each sensing agent that provides state estimates of the field. Optimal trajectory for the mobile sensor network in the advection-diffusion field is found, and distributed control laws to control the mobile sensor network to estimate and follow the trajectory while keeping a desired formation are designed. We prove that the parameter estimation errors are bounded and achieve parameter consensus. In addition, by generating a persistence of excitation condition, we further verify the asymptotic parameter convergence. Numerical simulations for 2-D and 3-D cases demonstrate the effectiveness of the proposed online passive identifier.

关键词： GAUSSIAN curvature   RIGIDITY (Geometry)   STRUCTURAL shells   DIRICHLET principle   EQUALITY  

摘要： In the paper we deal with shells with non-zero Gaussian curvature. We derive sharp Korn's first (linear geometric rigidity estimate) and second inequalities on that kind of shell for zero or periodic Dirichlet, Neumann, and Robin type boundary conditions. We prove that if the Gaussian curvature is positive, then the optimal constant in the first Korn inequality scales like h, and if the Gaussian curvature is negative, then the Korn constant scales like h(4/3), where h is the thickness of the shell. These results have a classical flavour in continuum mechanics, in particular shell theory. The Korn first inequalities are the linear version of the famous geometric rigidity estimate by Friesecke et al. for plates in Arch Ration Mech Anal 180(2): 183-236, 2006 (where they show that the Korn constant in the nonlinear Korn's first inequality scales like h(2)), extended to shells with nonzero curvature. We also recover the uniform Korn-Poincare inequality proven for "boundary-less" shells by Lewicka and Muller in Annales de l'Institute Henri Poincare (C) Non Linear Anal 28(3): 443-469, 2011 in the setting of our problem. The new estimates can also be applied to find the scaling law for the critical buckling load of the shell under in-plane loads as well as to derive energy scaling laws in the pre-buckled regime. The exponents 1 and 4/3 in the present work appear for the first time in any sharp geometric rigidity estimate.

关键词： Aggregated metadata   metadata   share   unique identifiers  

摘要： SHARE, an open metadata aggregator for scholarly content launched in 2013, provides access to dispersed scholarly content through a powerful application programming interface and set of tools for research discovery and analytics. Metadata is crucial for retrieval in systems like SHARE. The use of unique identifiers promotes the disambiguation of people, places, and objects and the linking of related information in aggregated systems. Yet, identifiers have not been uniformly adopted by organizations and institutions worldwide. This column seeks to identify and explore the extent of identifier use in the SHARE catalog. © 2017, Published with license by Taylor & Francis © 2017, © Cynthia Hudson-Vitale and Heather Moulaison Sandy.

关键词： 编程   标识符   unicode编码   中文标识符  

摘要： 编程中会遇到大量为常量、变量、对象命名的工作,命名称为标识符,几乎所有的计算机编程教材在介绍标识符命名时一律默认用的是英文,网上很多人说标识符只能使用英文字符。虽然也有人提到用中文标识符编译器可以通过,但为了避免意想不到的错误,不建议使用中文标识符。实际上只要支持unicode编码的编译器一律可以使用中文标识符,在编程中使用中文标识符,可以简化程序的代码数量,而且增加可读性。在我刚刚完成的一个软件中大量使用中文标识符,程序已正常运行数月,在此我要为中文标识符正名。

关键词： 数字对象   物理位置   identifier   数字信息   学术信息   数字化期刊   学术研究   被引频次   研究成果   持续追踪  

摘要： 数字对象唯一标识符（digital object identifier,DOI）是对包括互联网信息在内的数字信息进行标识的一种工具。在传统的出版物中,书刊、磁带、光盘都有国际标准编号（ISBN、ISSN、ISCN）及其条形码,作为出版物的唯一标识。这些标识使出版物得到有效的管理,便于读者查找和利用。而网上的文档一旦变更了网址便无从追索。数字信息标注DOI如同出版物的条形码,是一个永久和唯一的标识号。随着时间推移,数字对象的某些有关信息可能会有变化（包括存储的物理位置）,

关键词： 迷失   手指   1975年   大西洋   笔记本   标识符   秘密  

摘要： 在那艘1975年出厂的客轮上,遗落的红色封皮笔记本记录下了故事的背景：位于大西洋海域的＂迷失岛＂上藏着许多未被人知晓的秘密,玩家扮演的科顿博士,在好友卡卡先生的邀请下,来到神秘小岛上调查一系列的未知事件。上岛后你看到的所有东西都暗藏玄机,幸存船员的对话、墙上的标识符、明显有锁眼的机关,甚至零散的一草一木都是解谜的关键。你要想办法把它们联系在一起,通过智慧揭开层层谜题,探索出迷失岛最深处的秘密。

关键词： 数字信息   中华医学会   标注   杂志   object   出版物   国际标准   互联网  

摘要： 数字对象唯一标识符（digital object identifier，DOI）是对包括互联网信息在内的数字信息进行标识的一种工具。在传统的出版物中，书刊、磁带、光盘都有国际标准编号（ISBN、ISSN、ISCN）及其条形码，作为出版物的唯一标识。这些标识使出版物得到有效的管理，便于读者查找和利用。而网上的文档一旦变更了网址便无从追索。

关键词： 标识符   DOI   文献   国际标准   规范化管理   数字对象   信息技术   有效工具  

摘要： MDOI,即数字对象唯一标识,为英文DigitalObjectIdentification的缩写.根据国际标准ISO$26324里的解释,它的意思是“一个对象的数字标识符”.这个标识符具有唯一性、永久性的特点.DOI是规范化管理、组织、共享、利用数字资源的有效工具.随着信息技术和互联网的发展,DOI目前已在国际出版界得到广泛推广应用.

关键词： 中华医学会   数字信息   发表论文   管理学   杂志   健康   object   网络传播  

摘要： 数字对象标识符（digital object identifier，DOI）是对包括互联网信息在内的数字信息进行标识的一种工具，是一个可供全球期刊快速链接的管理系统，整个系统由国际DOI基金会（IDF）进行全球分布式管理。为了实现中华医学会系列杂志内容资源的有效数字化传播，同时保护这些数字资源在网络链接中的知识产权和网络传播权，自2009年第1期开始，中华医学会系列杂志纸版期刊和数字化期刊的论文已全部标注“DOI”，即中华医学会系列杂志除消息类稿件外，其他文章均需标注DOI。

关键词： CRISPR/Cas   genetic screening   massively parallel lineage tracing   unique molecular identifiers  

摘要： Loss-of-function screening by CRISPR/Cas9 gene knockout with pooled, lentiviral guide libraries is a widely applicable method for systematic identification of genes contributing to diverse cellular phenotypes. Here, Random Sequence Labels (RSLs) are incorporated into the guide library, which act as unique molecular identifiers (UMIs) to allow massively parallel lineage tracing and lineage dropout screening. RSLs greatly improve the reproducibility of results by increasing both the precision and the accuracy of screens. They reduce the number of cells needed to reach a set statistical power, or allow a more robust screen using the same number of cells.