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991.
992.
Lee S. Strickland 《Government Information Quarterly》2005,22(4):546-572
The founding fathers of the United States recognized that freely available information and an educated citizenry were essential to the functioning of a representative democracy. But almost as soon as the ink dried on the Constitution, political forces moved, and have continued to move, to restrict the flow of information from the government to the public, as well as among members of the public. This article examines whether information availability has become a victim of the war on terrorism – whether the nation has entered a time in which legal and policy initiatives are creating information gulags – secreting government information and restricting communications among members of the public, including the academic community. This article explores how policy is shaping the information relationship among the government, the public, academia, and the media and whether new models may be appropriate and more beneficial to society. In doing so, we examine in depth not only public access to government information but also the emerging and vital issue of government restrictions on scholarly exchange, as most recently presented by the legal dispute between the Institute of Electrical and Electronic Engineers (IEEE) and the Office of Foreign Asset Control (OFAC), Department of Treasury, and subsequently the litigation brought by the Association of American University Presses (AAUP). 相似文献
993.
E-mail-alerting system of online databases is a new trend catching up fast with researchers. Results of auto-run set queries are informed through e-mails as ‘alerts’ to the registered user. Even though e-mail-alerting systems are quite popular amongst Internet users, their inherent advantages remain unexplored in the Indian scenario. An effort to explore all such features available in the ScienceDirect online database has been made in this paper. The process of registration for activating e-mail alerts, customizing a home page, selecting favorite journals, search alerts, journal issue alerts, citation alerts and search history are briefed with screen shot examples. The study emphasizes the fact that librarians and information Science professionals should take lead roles in unveiling all such possible features available in various online databases. They should also make efforts at informing the user community of the utility of such features in a bid to enhance the research output. 相似文献
994.
N. M. Builova V. S. Egorov O. V. Kirillova L. M. Koroleva T. A. Pronina N. S. Soloshenko 《Scientific and Technical Information Processing》2007,34(6):301-304
The pilot issue of the data collection of the All-Russian Institute of Scientific and Technical Information of the Russian Academy of Sciences “Industry of Nanosystems and Nanomaterials” gives an approximate view of the state of this field of science at the beginning of 2007. The topics of articles in the pilot issue are analyzed. The directions of development of nanotechnologies are shown. The basic types of nanomaterials, the methods of their production, and their properties and applications are given. 相似文献
995.
996.
The publication activity of the scientists of the National Academy of Sciences of Belarus, the degree of reflection of their papers in Web of Science databases, and the data on the citation of Belarusian researchers in the studies of other scientists are discussed. 相似文献
997.
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
998.
999.
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
1000.
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