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关键词： identifier quality   part of speech   source code analysis  

摘要： Readers of programs have two main sources of domain information: identifier names and comments. In order to efficiently maintain source code, it is important that the identifier names (as well as comments) communicate clearly the concepts they represent. DeiBenbock and Pizka recently introduced two rules for creating well-formed identifiers: one considers the consistency of identifiers and the other their conciseness. These rules require a mapping from identifiers to the concepts they represent, which may be costly to develop after the initial release of a system. An approach for verifying whether identifiers are well formed without any additional information (e.g., a concept mapping) is developed. Using a pool of 48 million lines of code, experiments with the resulting syntactic rules for well-formed identifiers illustrate that violations of the syntactic pattern exist. Two case studies show that three-quarters of these violations are 'real'. That is, they could be identified using a concept mapping. Three related studies show that programmers tend to use a rather limited vocabulary, that, contrary to many other aspects of system evolution, maintenance does not introduce additional rule violations, and that open and proprietary sources differ in their percentage of violations. Copyright (C) 2007 John Wiley & Sons, Ltd.

关键词： 机床   机床部件   切削工具   刀片   标识符   技术规则   刀具   形状   式样  

标准号: GB/T 5343.1-2007

摘要： 本部分规定了矩形柄可转位车刀、仿形车刀及刀夹的型号表示规则，以利于简化订货和技术规范。已标准化了的矩形柄的尺寸f见GB／T 5343．2和GB／T l4661。 本部分适用于可转位车刀及刀夹的型号表示规则。

标准号: ETSI TS 129 230-2007

关键词： 流水号   计算机应用系统   单调上升   应用软件开发   单调下降   银行计算机   科技工作者   标识符   系统性能   系统主机  

摘要： 银行计算机应用系统在业务处理过程中产生的流水号十分重要,它是系统一定周期内一笔业务的唯一标识。因此在应用系统中,获取它的方法、手段就显得非常关键。我作为一名从事银行计算机应用软件开发的科技工作者,就此问题谈谈自己的体会。

关键词： rheumatoid arthritis   medical inpatient rehabilitation   work disability   RCT   health services research  

摘要： Aims: In a randomised controlled trial we examined the influence of a counselling (and implementation) of an inpatient rehabilitation programme on the somatic, mental and sociomedical course of rheumatoid arthritis (RA) in employees. Additionally, the recruitment of a study population via routine data of statutory health insurances was tested. Methods: Potential study participants were identified by health insurances via RA-specific data on work disability, hospital stays and medical prescriptions. These insurants entered a twostage selection process (postal screening questionnaire, experts). Eligible participants completed a postal questionnaire on their subjective health status, the responders were randomised into intervention group (IG) and control group (CG), respectively. The IG was offered a counselling on medical rehabilitation, CG members received usual care. Pension funds and health insurances transferred data on sick leaves (cases, days) hospital treatment, disability pension and medical rehabilitation (primary outcomes). Twelve months after baseline, again a questionnaire on subjective health status was completed (secondary outcomes). Data were analysed on an intention to treat and as actual basis. Results: Whilst the offered counselling was accepted very well (IG: 84.4%), the attendance in a medical inpatient rehabilitation was low (IG: 31.3%). Neither an intention to treat analysis (IG vs. CG) nor an as actual analysis (rehabilitation vs. no rehabilitation) perceived significant differences in the course of sick leave, hospital treatment or parameters of subjective health. Discussion: The study showed the feasibility of a randomised controlled trial in rehabilitationrelated Health Services Research. Recruitment via routine data of health insurances showed limitations. The low acceptance of a medical inpatient rehabilitation emphasises the need to establish alternative rehabilitative programs focussing on employed RA patients.

关键词： XML数据库模式   规范化设计   XML模式树   数据依赖   结构冗余   不规则   标识符  

摘要： XML数据库模式规范化设计是产生一组相关联的、能表示数据间依赖关系、而且消除了冗余的XML模式或DTD,其目的是为了互联网上的信息检索能够避免异常. XML数据库模式中某些数据依赖的存在是冗余存在的原因,因此在XML数据库模式中数据依赖与冗余的关联是其规范化设计研究的关键问题. XML数据库模式的数据依赖包括属性间数据依赖和元素间的数据依赖,与之关联的结构冗余和不规则是指在XML模式的结构上存在冗余和不规则的情况.给出综合了属性间和元素间数据依赖的XML数据库模式数据依赖的定义,分析与之关联的结构冗余以及不规则的情况,基于此定义消除结构冗余和不规则的规范的XML模式森林作为范式,给出并验证其规范化设计算法.

关键词： mobile robotics   system identification   non-linear modelling   NARMAX  

摘要： The lack of a theory-based design methodology for mobile robot control programs means that control programs have to be developed through an empirical trial-and-error process. This can be costly, time consuming and error prone. In this paper we show how to develop a theory of robot-environment interaction, which would overcome the above problem. We show how we can model a mobile robot's task (so-called "task identification") using non-linear polynomial models (NARMAX), which can subsequently be formally analysed using established mathematical methods. This provides an understanding of the underlying phenomena governing the robot's behaviour. Apart from the paper's main objective of formally analysing robot-environment interaction, the task identification process has further benefits, such as the fast and convenient cross-platform transfer of robot control programs ("Robot Java"), parsimonious task representations (memory issues) and very fast control code execution times. (c) 2007 Elsevier B.V. All rights reserved.

关键词： 数字资源   标识符   图书馆  

摘要： 数字资源唯一标识符对图书馆今后的发展有较大的影响。重视数字资源唯一标识符对加强我国数据库建设和管理具有重要意义。

关键词： 数字对象标识符   引文链接   牛津大学出版社   电子   联机期刊   技术报告   工作文件   学位论文  

摘要： 引文链接系统（CrossRef）始建于2000年初。到目前为止，该服务中已注册超过2500万条条目。尽管这些数字对象标识符大多数被分配到联机期刊的文章中，但是仍有超过200万的标识符串被分配到会议录、组件及图书中。引文链接也支持分配到技术报告、工作文件、学位论文、标准及数据元素的数字对象标识符。第2500万个数字对象标识符是由牛津杂志、牛津大学出版社注册给了《法国历史》（French History）。

关键词： 数字识别技术   电子出版物   标识符  

摘要： 数字识别技术是电子出版物标准化建设的一项重要内容。在电子出版物生产的不同环节,数字识别技术也存在不同,本文分别从制作出版和发行销售两个阶段,简要介绍了电子出版物的各种数字识别技术。