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81.
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   
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Serials, one of the more complicated areas of library technical endeavors, has lacked the benefit of standards for a long time. Even now, with standards beginning to be available, the majority of institutions are not working within standard serials formats. A survey to determine the use of serials standards in libraries was conducted in 1988 by the American Library Association, Resources and Technical Services Division, Serials Section, Committee to Study Serials Standards. In the spring of 1988 a survey was sent to a group encompassing the Association of Research Libraries members, CONSER participants, United States Newspaper Program participants, Microform Project libraries, and some vendors and librarians who attended the Committee meetings on a regular basis. The survey questionnaire assessed the current level of serials standards awareness of librarians and vendors. Topics included the type of serials systems used, standards relevant to serials control and union listing and whether or not they are implemented, types and levels of training staff received in the application of standards, benefits of the standards, and areas where standards are most needed.  相似文献   
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This article discusses HIV infection in terms of the risk manager's information needs in the health care environment. The malpractice problem, increasing workman's compensation suits, the greater role of the ombudsman, implementation of the National Practitioner Data Bank, and the Joint Commission on Accreditation of Health Care Organizations' (JCAHO) emphasis on clinical excellence are conditions which have given greater importance to the risk manager's position. Included in this article are hedges to retrieve various components of risk management and a select bibliography from AIDSLINE.  相似文献   
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The paper examines e-government development in Africa. This study is based on the Cape Gateway project in South Africa, a leading e-government initiative on the continent. We observe that African countries have jumped on the e-government band wagon by looking mostly at the benefits without a clear risk assessment. We argue that African countries should question the pace and pathway for their e-government programs. We caution that e-government models from developed countries do not necessarily work in Africa. E-government programs in Africa should be balanced with the provision of basic needs and infrastructure. We conclude that e-government in South Africa should adopt multi-cultural approaches, and must be underpinned by national development priorities. We recommend that the Cape Gateway must address the socio-economic context and needs of the country. The pace and pathway of its e-government must depend on the availability of both financial and human resources and also user satisfaction.  相似文献   
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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   
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The use of rural sites to train badly needed primary care providers requires access to sophisticated medical information not traditionally available outside of academic health centers. Medical reference librarians can play a key role in the development of primary care training sites in rural settings. Electronic information technologies, with proactive support from medical reference librarians, can provide current and detailed information without concern for distance from the health science center library. This paper discusses recent developments in technology, describes current challenges to the application of this technology in rural settings, and provides policy recommendations for medical reference librarians to enhance rural primary care training.  相似文献   
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