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101.
102.
Time series analysis was used to investigate the hypothesis that during acquisition of a motor skill, knowledge of results (KR) information is used to generate a stable internal referent about which response errors are randomly distributed. Sixteen subjects completed 50 acquisition trials of each of three movements whose spatial-temporal characteristics differed. Acquisition trials were either blocked, with each movement being presented in series, or randomized, with the presentation of movements occurring in random order. Analysis of movement time data indicated the contextual interference effect reported in previous studies was replicated in the present experiment. Time series analysis of the acquisition trial data revealed the majority of individual subject response patterns during blocked trials were best described by a model with a temporarily stationary, internal reference of the criterion and systematic, trial-to-trial variation of response errors. During random trial conditions, response patterns were usually best described by a "White-noise" model. This model predicts a permanently stationary, internal reference associated with randomly distributed response errors that are unaffected by KR information. These results are not consistent with previous work using time series analysis to describe motor behavior (Spray & Newell, 1986).  相似文献   
103.
EPIC is a service that provides keyword or subject access to the OCLC Online Union Catalog (OLUC). This capability increases the success rate for title location as well as the potential uses of the OLUC. The features of the EPIC system, application of these features to the OLUC, and specific uses in health sciences libraries are described in this article.  相似文献   
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105.
As a gatekeeper to medical literature and a critical link in the delivery of information to physicians, the librarian's role raises the issue of the librarian's professional liability. The paper suggests several ways in which liability may attach to the librarian or the librarian's employers. Although the librarian's personal risk is negligible, the physician's exposure due to ineffective library work is substantial since the courts have held that a physician must keep abreast of progress in his field. Librarians can also become associated with professional liability actions as part of a case against a physician or hospital through the legal doctrine of vicarious liability. The paper concludes by suggesting several proactive steps for health sciences librarians to pursue to insulate themselves from professional liability and to insulate physicians and institutions from vicarious liability.  相似文献   
106.
我们长期将数字图书馆作为一个独立的世界来构建,这个独立的世界中包括数字对象的创建、管理、发现、传递以及利用等。这种相对封闭的模式与高度发达的开放网络世界背道而驰。在网络世界中,用户可以通过大型的检索系统,如Google和Amazon来发现信息,还可以在管理这些信息资源的系统之外对其进行利用。当用户都涌向网络世界时,数字图书馆就面临着打破其固有封闭状态的挑战,以便适应开放的网络世界,否则将失去其实用性。当前,许多条件都给数字图书馆提供了改变现状、提高实用性的机遇。本文将讨论数字图书馆现存的典型模式以及该模式带来的后果,讨论数字图书馆工作改革的方式,并简要探讨数字图书馆建设中的成功技术实例。  相似文献   
107.
Information access is central to library and information science, yet explorations of its conceptual nature have been limited. Given the importance of information access to the discipline, there is a need for research to create a better understanding of the concept and its many roles in all activities and behaviors related to information. Drawing on the theoretical work of Elfreda Chatman, this article proposes that the study of information access can be facilitated through the recognition and examination of the physical, intellectual, and social aspects of information access. These types of access are examined through three case studies in terms of different information behaviors and contexts, with a particular focus on the importance of social access. The article also discusses the future roles that considerations of social access can play in research and theory.  相似文献   
108.
Governments worldwide are increasingly using Web-based business models to enhance their service delivery. Yet the concept of the business model is unexplored within the context of e-government. Drawing upon the literature on e-commerce, we develop a taxonomy for analyzing Web-based business models for e-government. Based on a systematic survey of 59 e-government Web sites in the Netherlands, our findings indicate that most of the Web sites use the content provider or direct-to-customer business models, while only a few are using novel business models. Overall, the concept of business model is appealing and useful in the public sector. Specifically it compliments research on Web site quality by analyzing and describing Web sites using atomic e-government business models and suggesting improvements by using combinations of business models.  相似文献   
109.
Web sites are increasingly used by academic libraries to promote key services and collections to teaching faculty. This study analyzes the content, location, language, and technological features of fifty-four academic library Web pages designed especially for faculty to expose patterns in the development of these pages.  相似文献   
110.
This paper discusses the evaluation of scientific activity with the help of some scientometric indices, in particular, a citation index. The information massif of the bibliographic database of citations to domestic publications of Kazakh authors is statistically described.  相似文献   
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