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关键词： 身份加密   电子邮件   电子商务   证书签名   标识符   身份认证   私钥生成   安全传送  

摘要： 随着Internet的快速发展，电子邮件也得到了越来越广泛的应用。然而传统的电子邮件存在的若干不安全因素(如邮件可能在不为通信双方所知的情况下被读取、篡改和伪造)，使重要的需要保密的信息还不能通过电子邮件传送，阻碍了电子邮件在电子商务和电子政务中的应用。因此迫切需要一种有安全保证的电子邮件系统。\n 基于传统的公钥密码体制和证书的系统，在使用过程中需要完成一系列对证书的操作和管理，包括证书的签名、发布、获取、验证、存储、撤销等。而IBE则直接以用户的Email地址、角色、任务等标识符作为公钥，不需要证书和相关操作，简化了公钥的使用与管理，系统构成也很简单，只需设立信任机构TA完成用户身份认证、权限检查、私钥生成和安全传送，具有易于实施、使用方便等优点。\n 本文介绍了基于身份加密的算法原理、基于数论中二次剩余的Cocks方案和基于椭圆曲线双线性映射的Boneh-Franklin方案。在此基础上设计了一个 Windows平台上基于身份加密的安全电子邮件系统，这个系统通过插件的形式和Microsoft Outlook嵌入，在发邮件时自动加密，签名；在阅读邮件时验证签名和解密。系统组成主要有信任机构TA中心、加密模块、签名模块、解密模块和验证签名模块。

关键词： .unique   San Francisco   periods   separated   randomization   discriminant   procedure   annual cycle   trace elements   feathers of western   sandpipers   different wintering sites   Bay of Panama  

摘要： Understanding the ecology and evolution of migratory animals requires information on how populations are geographically linked between periods of the annual cycle. To examine whether trace elements could be used to track migratory birds, we analyzed concentrations of 42 trace elements in feathers of western sandpipers (Calidris mauri (Cabanis, 1857)) that were grown at five different wintering sites ranging from San Francisco Bay (USA) to the Bay of Panama. Linear discriminant analysis of 15 elements correctly classified all 26 individuals to their wintering sites, including two sites that were separated by less than 3 km. A randomization procedure confirmed the robustness of these findings. Our analysis suggests that trace elements can be used to assign individuals to specific sites of origin. Although we did not sample feathers from all wintering areas, the regions our sites represented comprised a significant percentage of the global population. However, since trace element profiles appear to be highly specific to geographic sites, we suggest that this technique is best suited for cases where samples can be obtained from the majority of populations throughout a species range. Thus, under certain circumstances, trace element profiles may provide the potential to identify populations with a high degree of spatial accuracy.

关键词： Health insurance -- United States   Health planning   Medical policy  

摘要： The article discusses the National Provider Identifier, a new provision of the Health Insurance Portability and Accountability Act in the U.S. The new provision will help the health plans by providing all health care providers a unique identification number and thus making the billing process simple and easy. The relevance of the act to the employer health care plans is also discussed in the article.

关键词： cancer   demography   regional differences   elderly   aging population  

摘要： The use of regional demography is relevant in managing and anticipating the cancer care needs of the elderly. The increase in life expectancy and decline in fertility in European societies are responsible for the growing demographic weight of the elderly population. Geographic analyses of space-time changes in the elderly population show that the changes are not homogeneous throughout French territory;there are differences between urban and rural areas, within urban areas, and between the sexes, as well as disparities between regions, based on immigration and emigration. These territory dynamics parallel significant changes in the living conditions of elderly people (living alone or in residences).

关键词： 电控单体泵   节点   标定   位时间   标识符  

摘要： 随着车载电控单元数量的增多,实现多节点同时标定有利于汽车不同ECU间的参数匹配优化,在设计了TouCAN模块与CAN总线硬件接口的基础上,结合CCP协议,通过设置位时间、不同的节点站地址、收发报文缓冲器的标识符及屏蔽寄存器,设计并实现了多个ECU的通信和标定,提高了标定效率。

关键词： 数字对象标识符   系统组成   电子出版   DOI系统  

摘要： 系统介绍分析了数字对象标识符(DOI)系统的概念及其构成,阐述DOI系统的功能特征,探讨DOI在电子出版方面的作用,并根据其应用情况提出一些建议。

关键词： Artificial intelligence   Bayesian probability models   Cleaning databases   Data integration   Master list of patients   Patient identification   Re-identification   Statistical inference  

摘要： We show how Bayesian probability models can be used to integrate two databases, one of which does not have a key for uniquely identifying clients (e.g., social security number or medical record number). The analyst selects a set of imperfect identifiers (last visit diagnosis, first name, etc.). The algorithm assesses the likelihood ratio associated with the identifier from the database of known cases. It estimates the probability that two records belong to the same client from the likelihood ratios. As it proceeds in examining various identifiers, it accounts for inter-dependencies among them by allowing overlapping and redundant identifiers to be used. We test that the procedure is effective by examining data from the Medical Expenditure Panel Survey (MEPS) Population Characteristics data set, a publicly available data set. We randomly selected 1,000 cases for training data set-these constituted the known cases. The algorithm was used to identify if 100 cases not in the training data set would be misclassified in terms of being a case in the training set or a new case. With 12 fields as identifiers, all 100 cases were correctly classified as new cases. We also selected 100 known cases from the training set and asked the algorithm to classify these cases. Again, all 100 cases were correctly classified. Less accurate results were obtained when the training data set was too small (e.g., less than 100 records) or the number of fields used as identifiers was too small (e.g., less than seven fields). In a test of performance of the algorithm, when the ratio of testing to training data set exceeds 4 to 1, the accuracy of the algorithm exceeded 90% of cases. As the ratio increases, the accuracy of algorithm improves further. These data suggest the accuracy of our automated and mathematical procedure to merge data from two different data sets without the presence of a unique identifier. The algorithm uses imperfect and overlapping clues to re-identify cases from information

关键词： 终端   终端设备   规范   规   自营电通信  

标准号: NKR 平成6年郵政省告示第424号-2007

关键词： AutoCAD   AutoLISP程序   钢筋面积结果   钢筋标识类别  

摘要： 程序使用概览、程序运行过程简介,本程序可直观,迅速、准确的获得和编辑钢筋面积、直径。

关键词： 数字对象标识符   电子出版   DOI   应用   网络资源   保护知识产权   不稳定性   标识系统  

摘要： 由于现行的网络资源标识系统U R L的不稳定性和易变性,推出并实行一种稳定可靠的、既能保护知识产权又能实现版权所有者商业利益的网络资源标识系统的想法应运而生。目前,不同领域存在多种资源编码规范,但在数字出版系统中以数字对象标识符DOI(Digital Object Identifier)最为普及。1998年国际数字对象标识符基金会(International DOIFoundation,IDF)在法兰克福成立,专门负责数字对象标识符的运作。IDF是一个非盈利性的组织,在网页上提供DOI手册以供使用,内容包括DOI技术、组成框架、使用方法、管理方式等,目前最新版为2006年5月发行的4.3.0版,可从http://***/***下载使用。目前,IDF发出数字对象标识符已超过二千万个,足见其影响力之大。DOI系统的特点DOI系统的主要功能在于给数字对象分配全球永久惟一的标识符,其本身是由一串数字组成,但要体现它的价值,还需要解析系统正确的解译、元数据适当正确的描述以及注册者自行定义的合适编码组合等,DOI系统由四个部分组成:D O I编码、D O I描述、D O I解析和D O I政策,详...