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61.
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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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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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   
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At this critical point in its development as a burgeoning market economy ensconced within a socialist political system, China faces a dilemma in becoming a fully‐fledged player in the copyright arena. Over the past two decades, China has made great strides in creating a legal and governmental framework for the administration and enforcement of copyright. But its implementation has left much to be desired, owing partly to inadequate resources of money and personnel, partly to insufficiently harsh penalties for infringement, partly to cumbersome procedures required to bring action against infringers, and partly to a general cultural tolerance for practices that run contrary to cultivating a broad‐based respect for copyright. This article proposes that a balance of pressure and encouragement is likely to have the best chances of success in overcoming these problems and ensuring that China will become fully welcomed into the international publishing community.  相似文献   
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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   
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