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141.
142.
A transaction log analysis of the Nanyang Technological University (NTU) OPAC was conducted to identify query and search failure patterns with the goal of identifying areas of improvement for the system. One semester’s worth of OPAC transaction logs were obtained and from these, 641,991 queries were extracted and used for this work. Issues investigated included query length, frequency and type of search options and Boolean operators used as well as their relationships with search failure. Among other findings, results indicate that a majority of the queries were simple, with short query lengths and a low usage of Boolean operators. Failure analysis revealed that on average, users had an almost equal chance of obtaining no records or at least one record to a submitted query. We propose enhancements and suggest future areas of work to improve the users’ search experience with the NTU OPAC. 相似文献
143.
A new delayed state-variable model for networked control systems is presented, upon which a linear quadratic regulator (LQR) is designed. A method of delays-estimation online is also given. A fuzzy logic with LQR controller is addressed for the difficulty on implementation of LQR in networked control systems (NCSs) with time-variant delays. Simulation results prove that the novel controller can make the system stable and robustly preserve the performance in terms of time-variant delays. 相似文献
144.
国内图书馆学人学术性博客浅析 总被引:16,自引:1,他引:16
博客作为一种新的网络交流方式,已引起人们的广泛关注。本文根据依托服务器的不同将国内图书馆学人创办的学术性博客划分为通过“博客中国”创办、通过“网络图苑”创办、通过“e线图情”创办、通过“数图之家”创办和通过其他渠道创办等5种类型,并进行了简要分析。在此基础上,就博客的创建与阅读谈几点建议。 相似文献
145.
参考咨询服务在信息时代的拓展 总被引:13,自引:0,他引:13
文章首先论述了信息时代参考咨询服务的发展走向,然后论述了面临新的环境,参考咨询服务必须拓展服务方式、服务内容。 相似文献
146.
Domesticating Computers and the Internet 总被引:1,自引:0,他引:1
The people who use computers and the ways they use them have changed substantially over the past 25 years. In the beginning highly educated people, mostly men, in technical professions used computers for work, but over time a much broader range of people are using computers for personal and domestic purposes. This trend is still continuing, and over a shorter time scale has been replicated with the use of the Internet. This paper uses data from four national surveys to document how personal computers and the Internet have become increasingly domesticated since 1995 and to explore the mechanisms for this shift. Now people log on more often from home than from places of employment and do so for pleasure and for personal purposes rather than for their jobs. Analyses comparing veteran Internet users to novices in 1998 and 2000 and analyses comparing the change in use within a single sample between 1995 and 1996 support two complementary explanations for how these technologies have become domesticated. Women, children, and less well-educated individuals are increasingly using computers and the Internet and have a more personal set of motives than well-educated men. In addition, the widespread diffusion of the PC and the Internet and the response of the computing industry to the diversity in consumers has led to a rich set of personal and domestic services. 相似文献
147.
新形势下高新技术产业技术创新政策的探讨 总被引:5,自引:0,他引:5
新形势下政府对产业技术创新政策的制订影响到高新技术产业的发展效率和速度,从分析技术创新政策的基本内涵入手,提出政府实施新的技术创新政策的必要性,并针对目前中国高新技术产业技术创新的现状和问题,提出促进高新技术产业发展的技术创新政策。 相似文献
148.
In the United States, Congress has had a long-standing interest in consumer privacy and the extent to which company practices are based on fair information practices. Previously, public policy was largely informed by anecdotal evidence about the effectiveness of industry self-regulatory programs. However, the Internet has made it possible to unobtrusively sample web sites and their privacy disclosures in a way that is not feasible in the offline world. Beginning in 1998, the Federal Trade Commission relied upon a series of three surveys of web sites to assess whether organizations post online privacy disclosures and whether these disclosures represent the U.S. definition of fair information practices. While each year's survey has provided an important snapshot of U.S. web-site practices, there has been no longitudinal analysis of the multiyear trends. This study compares a subset of equivalent individual-level web-site data for the 1998, 1999, 2000, and 2001 web surveys. Implications for using this type of research to inform public policy are discussed. 相似文献
149.
Researching Internet Communities: Proposed Ethical Guidelines for the Reporting of Results 总被引:4,自引:0,他引:4
Storm A. King 《The Information Society》1996,12(2):119-128
Communication researchers and social scientists are quickly discovering the value of data that exists in the postings of members of Internet e-mail, Usenet, and real-time groups. The ability to communicate with one's peers, no matter how esoteric the interests, is causing an explosion in the number of new virtual communities. The interpersonal dynamics of these groups are increasingly coming under the scrutiny of academic research. The publicly available archived records of Internet virtual communities are being analyzed for a wide variety of research interests. The ability to do naturalistic observations of group dynamics, as they are exhibited in these exchanges of text, has captured the attention of many researchers. The institutional review boards of major universities are granting researchers exempt or expedited (exempt from full review) status for this work, due to the public nature of the notes being analyzed. These studies often involve the lack of informed consent, where the group members under study are unaware they are being monitored. There is a potential for psychological harm to the members of these groups, depending on the way results are reported. This article explores the ethical considerations that must be taken into account to protect cyberspace participants. The guidelines proposed are based on the American Psychological Association ethical guidelines for use of human subjects in research. An explanation is offered as to how such guidelines can best be applied to the study of Internet communities. The constructs of Group Accessibility (the public/private nature of the actual cyberspace occupied by a group) and Perceived Privacy (the level of privacy that group members assume they have) are defined and proposed as two dimensions by which individual Internet communities may be evaluated in order to assure the ethical reporting of research findings. 相似文献
150.
本文在介绍Tradeline文档的基础上,探讨了通过Dialog系统的检索证券信息的方法,并指出,在因特网上充斥着大量免费信息的情况下,Dialog系统仍然是证券投资类研究人员重要的情报源。 相似文献