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关键词： Multivariate analysis   Nonparametric   Robust   Outlier identification   Depth functions  

摘要： In extending univariate outlier detection methods to higher dimension, various issues arise: limited visualization methods, inadequacy of marginal methods, lack of a natural order, limited parametric modeling, and, when using Mahalanobis distance, restriction to ellipsoidal contours. To address and overcome such limitations, we introduce nonparametric multivariate outlier identifiers based on multivariate depth functions, which can generate contours following the shape of the data set. Also, we study masking robustness, that is, robustness against misidentification of outliers as nonoutliers. In particular, we define a masking breakdown point (MBP), adapting to our setting certain ideas of Davies and Gather [1993. The identification of multiple outliers (with discussion). journal of the American Statistical Association 88, 782-801] and Becker and Gather [1999. The masking breakdown point of multivariate outlier identification rules. journal of the American Statistical Association 94, 947-955] based on the Mahalanobis distance outlyingness. We then compare four affine invariant outlier detection procedures, based on Mahalanobis distance, halfspace or Tukey depth, projection depth, and "Mahalanobis spatial" depth. For the goal of threshold type outlier detection, it is found that the Mahalanobis distance and projection procedures are distinctly superior in performance, each with very high MBP, while the halfspace approach is quite inferior. When a moderate MBP suffices, the Mahalanobis spatial procedure is competitive in view of its contours not constrained to be elliptical and its computational burden relatively mild. A small sampling experiment yields findings completely in accordance with the theoretical comparisons. While these four depth procedures are relatively comparable for the purpose of robust affine equivariant location estimation, the halfspace depth is not competitive with the others for the quite different goal of robust setting of an outlyingness thres

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

摘要： 数字对象惟一标识符（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，作为出版物的惟一标识。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： 中华医学会系列杂志   标注   数字信息   出版物   国际标准   条形码   互联网  

摘要： 数字对象惟一标识符（digital obiect 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（IS—BN、ISSN、ISCN）及其条形码，作为出版物的惟一标识。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，是一个永久和惟一的标识号。

关键词： 数字信息   2009年   中华医学会   标注   杂志   object   出版物   国际标准  

摘要： 中华医学会系列杂志从2009年开始标注数字对象惟一标识符数字对象惟一标识符（digital object identifier，DOI）是对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，作为出版物的惟一标识。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，是一个永久和惟一的标识号。

关键词： 医学杂志   object   论文   标注  

摘要： 自2010年第1期开始，《实用医学杂志》全面启用数字对象唯一标识符（digital object identifier，DOI），即对每一篇刊出的论文都标注DOI。本刊DOI统一标注于论文首页左下角脚注的第1项，标注规则为：doi：10．3969／***．1006—***。其中“doi：10．3969／***．1006—5725．”部分保持永久不变，“yyy”4位指出版年份，“nn”2位指期号，“zzz”3位指本期论文流水号。如《实用医学杂志》2010年第1期第1篇论文的DOI为：doi：10．3969／***．1006—5725．2010．01．001。

关键词： QSPR   InChI   Normal boiling point   Acyclic carbonyl compounds  

摘要： Optimal descriptors calculated with international chemical identifier have been used to construct one-variable model of the normal boiling points of acyclic carbonyl substances. Attempts to calculate the model for three splits into training and test sets gave stable results. Statistical quality of the model is n = 150, r (2) = 0.9825, s = 4.96 A degrees C, F = 8,312 (training set) and n = 50, r (2) = 0.9791, s = 4.68 A degrees C, F = 2,249 (test set).

关键词： DOI   中文数字对象唯一标识符   参考文献   引文链接   分割标引  

摘要： 在国外,数字对象唯一标识符系统(DOIs)在原文获取、引文链接与数字版权管理中已有广泛的应用。中文数字对象唯一标识符系统(ChDOIs)的建立与发展迫在眉睫。从参考文献著录与数字对象唯一标识符(DOI)的关系这一独特视角出发,理清DOI多重解析的原理和具体应用模式,以及中文信息资源面对DOI多重解析在实际运行时可能遇到的问题。在调研部分电子资源平台上DOI在参考文献中的标引情况后,详细分析了中文DOI发展的局限性及其原因,并提出ChDOIs的发展建议,即自主建立系统、文后著录DOI、分割标引参考文献。图2。参考文献20。

关键词： 高宽比   彩色印刷   数据交换   数据格式   数据输出   定义   数字的   数字数据   图形技术   印刷业   成象   元数据   PDF   印刷   标识符  

标准号: ISO 15930-7-2010

摘要： This part of ISO 15930 specifies the use of the Portable Document Format (PDF) Version 1.6 for the dissemination of digital data intended for print reproduction. When all elements necessary for final print reproduction are contained within the file, it is designated as PDF/X-4. If a required ICC profile is externally supplied and unambiguously identified, it is designated as PDF/X-4p.

摘要： 数字对象惟一标识符(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,作为出版物的惟一标识。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,是一个永久和惟一的标识号。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),而DOI可让使用者直接由此链接到出版商的数据库、文献、摘要甚至是全文,识别码可以直接指引到出版物的本身,使国内外各种来

关键词： identifier   institutional fact   brute fact   information infrastructure   ontology   database design   information systems development   speech act   pragmatic meaning  

摘要： Identifiers - such as personal identification numbers, student numbers, and license numbers - are used for identifying individual objects and constitute an important part of the information infrastructures of organizations and society. The design, choice, assignment, withdrawal, and replacement of identifiers are significant economic and political issues with more profound consequences than are perhaps commonly perceived. Use of identifiers can result in significant costs because they may include descriptive information, because an inappropriate identifier may be chosen for the object in question, or because there may be a lack of institutional control of the identifier. The objective of this paper is to elaborate on these problems by explaining the identifier construct from a technical, institutional, ontological, and information infrastructural perspective. Based on this understanding, we provide guidelines for how identifiers should be designed, chosen, replaced, and controlled. Accordingly, we address the practical need for improved design principles relating to the increasingly important infrastructural character of computerized information systems that stems from the importance of appropriate identifiers for information infrastructures and society as a whole. In order to understand the role, function, and meaning of identifiers, it is important to acknowledge that the identifier is fundamentally a linguistic construct used when referring to socially constructed institutional objects. Institutional objects are symbolic entities that represent institutional and brute facts, which are the results of human actions.