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Acquiring both published and unpublished documents produced in Africa is, generally, a difficult task due to the existing poor state of bibliographic control and the publishing industry. It is even more difficult to obtain unpublished documents in a specialized area of study such as demography--a diffuse area which cuts across several disciplines. This paper discusses the problems encountered on acquisition trips to some African countries to acquire unpublished population material. To help solve the problems, the Population Association of Africa must persuade its members to send copies of their publications to population libraries and documentation centers in their individual countries for dissemination to the other users in Africa. The various organizations and institutions in Africa engaged in the teaching and research of population studies should have an agreement to exchange copies of their theses. The Economic Commission for Africa (ECA) and the Organization of African Unity (OAU) should make representations to the various African member countries on the need to disseminate the results of vital censuses and surveys conducted. Finally, the Population Information Network for Africa (POPIN-AFRICA) with its coordinating unit at the population division of ECA should ensure that all the nodes of the network have the financial and other resources to be able to acquire the relevant documents needed for their operations.  相似文献   
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The National Library of Medicine has had an enormous impact on health information services all over the world. Although NLM is primarily a national institution, it has become an important international resource by responding to requests from the international community. NLM has been influential in three major ways. First, NLM has provided a model for other national and regional health information services. Second, it has been a catalyst, in that MEDLARS and other services it provides formed the nucleus of many regional networks. NLM helped such networks get started by giving advice on how to set up services and build collections and by "training the trainers" on the MEDLARS system. Third, NLM has supported national and regional operations by providing the additional training and materials needed for day-to-day service.  相似文献   
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Questions concerning some of the values we hold as librarians and the goals, standards, and other evaluation tools we derive from them are discussed in the context of the history of our profession and the present period of rapid change. The concepts of stable and changing paradigms and of "scientific communities" provide the foundation for consideration of how a changing conceptual framework can affect values and their application in the evaluation process. One of many possible scenarios for the future is briefly outlined to demonstrate how some traditional values may fare.  相似文献   
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Knowing is an enacted, communicated process that is difficult to observe, let alone manage, in organizations. Communities of practice (CoPs) offer a productive solution for improving knowledge and knowledge management, but the communicative processes that enact CoPs have not been explored, leaving CoPs as an organizational black box. This research extends CoP theory as a means to determine the presence of a CoP and distinguish between various CoPs, and as a practical means to evaluate the communicative processes of organizational knowledge. CoPs enact the communicative nature of knowing through the elements of mutual engagement, negotiation of a joint enterprise, and shared repertoire. Specifically, two groups of volunteers are examined through a combination of participation, observation, and interviews in order to explore CoP theory as a dynamic system for examining and evaluating organizational knowledge.  相似文献   
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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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