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关键词： 数字对象唯一标识符  

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。

关键词： IP地址管理   全球互联网   核心平台   域名   ICANN   分配和管理   互联网大国   标识符  

摘要： 互联网名称与数字地址分配机构(ICANN)作为全球互联网IP地址和域名资源的分配和管理机构,是国际多利益攸关方共同参与互联网域名系统根区管理、互联网协议(IP)地址空间分配、协议标识符指派及与域名和IP地址管理相关政策制定的核心平台。我国作为互联网大国,域名行业从业主体众多。

关键词： 条形码   数字信息   数字对象唯一标识符   网址   互联网信息   唯一标识   信息标注  

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(ISBNJSSNJSCN)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D0I如同岀版物的条形码,是一个永久和唯一的标识号。

关键词： 国际标准书号   ISBN   ISBN-A   标识符   图书   专题出版物  

摘要： 《国际标准书号ISBN》是应图书出版、管理的需要,便于国际间出版品的交流与统计所制定的一套国际统一的编号。自颁布以来,目前已在166个国家和地区广泛应用。经历了四次修订之后,2014年该标准启动了第5次修订工作,修订后的第五版标准于2017年底正式发布。在新修订的版本中,标准加强了对数字出版物的标识描述,细化了数字出版物的标识原则,这必将对各国如何管理数字出版物产生重要影响。本文从该国际标准修订工作情况出发,详细介绍了最新版的《国际标准书号ISBN》如何解决数字出版物的标识问题,分析了该标准应用可能会产生的影响和其中一些关键问题。

标准号: T/CQCADPA 3-2021

关键词： Mandelbrot set   Moire patterns   Space-time discretization   Fixed-Point representation   IEEE Floating-Point representation   Source/Hyperbolic Points  

摘要： In the calculation of the map of periods of the Mandelbrot Set and working with fixed-point and floating-point real number representation systems, moire interference patterns always appear. These result from the discretization that every computer sets in the finite encoding of its real values. It is not known from which original layers such interferences are obtained and how these initial layers are generated. This article aims at answering these two questions. In order to search these original layers thousands of images-created by means of two different encodings of the real values and with different accuracies-of the map of periods were analyzed. Some points with constant location, called Source Points, around which regular patterns with hyperbolic configuration are generated, were located as well. This answers the questions regarding the cause and origin of moire interferences. Some characteristics of Source Points are described hereinafter. It is also justified why moire interferences in the plane of periods have a hypersensitive behavior. Finally, it is shown how in dynamic systems accuracy does not only affect the precision of results, but also the configuration of the results themselves. The following interesting reflection is, therefore, open to discussion: if the real world should be seen with a fractal way of looking, accuracy configurates then the essence of everything. (c) 2019 Elsevier B.V. All rights reserved.

关键词： Magnetic seeds   radiofrequency identification tags   nonwire localisation  

摘要： Background: Wire-guided localisation ( WGL) remains the most widely used technique to guide surgical excision of non-palpable breast lesions worldwide. However, recent technological advances have led to the advent of less invasive radiation-free localisation methods to overcome the limitations of WGL. Patients and Methods: This study prospectively evaluated the role of two radiation-free nonwire localisation methods. Magnetic seeds (n=16) and radiofrequency tags (n=6) were deployed under imaging guidance to guide the surgical excision in 19 consecutive patients. Results: The identification/retrieval and migration rates were 100% and 4.5%, respectively. Twenty-one out of 22 (95.5%) cases had clear surgical margins and no complications were observed. All radiologists and the surgeon rated these methods as being much better than wire localisation. Patient satisfaction data were recorded using a linear visual analogue scale (n= 10/19). The mean score was 9.7/10 (range=8-10). Conclusion: Our study provides further evidence that radiation-free wireless breast localisation is an effective alternative to WGL.

关键词： 磁盘加密   移动设备   标识符   查看器   控制台  

摘要： 做过IT系统运维管理任务的人们都知道,无论是Email邮箱密码、网域帐户密码、网站应用程序密码,还是个人计算机密码,总是会有用户忘记密码,这时候IT人员就得想办法进入后台,来将他的密码改为一组默认值。像这样的情形在许多Windows计算机都启用了

标准号: CY/T 208-2020

标准号: ISO/IEC 23736-6-2020