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941.
The paper is devoted to the problem of the qualitative training of management specialists. New methods and instruments permitting the quality of accepted decisions to be heightened are described. It is suggested to use an SISDM containing the functions of the system as an instrument for planning decisions and training in decision making with the use of computerized methods for the active teaching of the method for the analysis of concrete situations and management games. 相似文献
942.
A pipelined architecture for distributed text query evaluation 总被引:1,自引:0,他引:1
Alistair Moffat William Webber Justin Zobel Ricardo Baeza-Yates 《Information Retrieval》2007,10(3):205-231
Two principal query-evaluation methodologies have been described for cluster-based implementation of distributed information
retrieval systems: document partitioning and term partitioning. In a document-partitioned system, each of the processors hosts
a subset of the documents in the collection, and executes every query against its local sub-collection. In a term-partitioned
system, each of the processors hosts a subset of the inverted lists that make up the index of the collection, and serves them
to a central machine as they are required for query evaluation.
In this paper we introduce a pipelined query-evaluation methodology, based on a term-partitioned index, in which partially
evaluated queries are passed amongst the set of processors that host the query terms. This arrangement retains the disk read
benefits of term partitioning, but more effectively shares the computational load. We compare the three methodologies experimentally,
and show that term distribution is inefficient and scales poorly. The new pipelined approach offers efficient memory utilization
and efficient use of disk accesses, but suffers from problems with load balancing between nodes. Until these problems are
resolved, document partitioning remains the preferred method.
Alistair Moffat was supported by the Australian Research Council, the ARC Special Research Center for Perceptive and Intelligent
Machines in Complex Environments, and the NICTA Victoria Laboratory.
William Webber and Justin Zobel were supported by the Australian Research Council.
Ricardo Baeza-Yates was supported by Grant P01-029-F from Millennium Initiative of Mideplan, Chile; and by the University
of Melbourne as a visiting scholar at the time this project was undertaken. 相似文献
943.
944.
Robert E. Baensch 《Publishing Research Quarterly》2007,23(4):262-269
The essential demographic data and related information for India is provided specifically for the publishing industry. The
focus has been placed on the economics, education and computer industry in relation to the complex cultural factors of different
languages and religions. The role of India in relation to the other three BRIC countries or Brazil, China and Russia is explored. 相似文献
945.
Jacques Savoy 《Information Retrieval》2007,10(6):509-529
This paper reports on the underlying IR problems encountered when indexing and searching with the Bulgarian language. For
this language we propose a general light stemmer and demonstrate that it can be quite effective, producing significantly better
MAP (around + 34%) than an approach not applying stemming. We implement the GL2 model derived from the Divergence from Randomness paradigm and find its retrieval effectiveness better than other probabilistic, vector-space and language models. The resulting
MAP is found to be about 50% better than the classical tf idf approach. Moreover, increasing the query size enhances the MAP by around 10% (from T to TD). In order to compare the retrieval
effectiveness of our suggested stopword list and the light stemmer developed for the Bulgarian language, we conduct a set
of experiments on another stopword list and also a more complex and aggressive stemmer. Results tend to indicate that there
is no statistically significant difference between these variants and our suggested approach. This paper evaluates other indexing
strategies such as 4-gram indexing and indexing based on the automatic decompounding of compound words. Finally, we analyze
certain queries to discover why we obtained poor results, when indexing Bulgarian documents using the suggested word-based
approach. 相似文献
946.
947.
948.
LaBeause J Van de Water N Carey P Fielder M Sorrow B Woolbright C 《Medical reference services quarterly》1999,18(2):81-89
Health sciences librarians are being called upon to be more proactive in their institutions' continuing education efforts. In an effort to identify whether search requests indicated CE needs, a study was conducted by a group of members of GaIN (Georgia Interactive Network for Medical Information). MEDLINE requests from health care professionals for subject specific clinical topics were collected during a six-month period via a standard search request form created for the study. Copies of all completed requests were collected and broad ICD-9 codes assigned to the search topics. Institutional reports were generated for each participating library to share with hospital CE coordinators. They were also compiled for the group as a whole, and reflected the "hottest" topics requested during the study period for physicians and for non-physicians (nurses, allied health, administrators). A survey to hospital librarians and CE educators showed some value in the reports, but greater potential for further collaboration between librarians and CE coordinators. 相似文献
949.
This paper documents the evolving uses of the Internet made by public health graduate students and traces the development of their search methods and critical evaluative criteria. Early in the first semester and again six months later, twenty-four graduate students in a problem-based learning curriculum, which emphasizes evidence-based critical thinking skills, were required to describe their most helpful resources and to evaluate these resources critically. The answers were coded for the types of resources the students used, how frequently they were used, and why they were used. Student perception of the usefulness of resources, especially the Internet, and ability to evaluate these resources critically changed greatly. Initially, 96% of the students stated that the Internet was their most helpful resource. Six months later, these students continued to use the Internet; however, it was not their most useful source. At the later point, students had very specific uses for the Internet. Their most frequently used evaluation criterion was the reliability and objectivity of the source of the information. By the end of the first year of study, the majority of the students demonstrated an understanding of the principles of evidence-based practice and applied them to their research and analysis of information resources. 相似文献
950.
社会需要与武术的发展 总被引:1,自引:0,他引:1
程江陵 《体育成人教育学刊》2002,18(3):17-18
中华武术 ,从其萌发、产生、演变和发展至今 ,都是受中国社会经济发展和社会需要的影响和推动。在新的社会时期 ,武术如何适应现代社会需要 ,并在国内、国外蓬勃发展起来 ,是我们武术工作者目前面临的一个严肃问题。 相似文献