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941.
Lucio Lubiana Julia A. Gammon 《Library Collections, Acquisitions, and Technical Services》2005,28(4):373-396
The book market in European countries is different than the U.S. market for various political, geographical, and cultural reasons. The authors outline these differences and provide background on the move to electronic commerce and future. The article includes many electronic and print sources of and bibliographic tools for locating books in the European market. 相似文献
942.
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
943.
Wolfgang Schr?der-Preikschat Daniel Lohmann Fabian Scheler Olaf Spinczyk 《Informatik - Forschung und Entwicklung》2007,22(1):5-22
Design, implementation, and re-engineering of operating systems are still an ambitious undertaking.
Despite, or even because, of the long history of theory and practice in this field, adapting existing systems
to environments of different conditions and requirements as originally specified or assumed, in terms of
functional and/or non-functional respects, is anything but simple. Especially this is true for the embedded
systems domain which, on the one hand, calls for highly specialized and application-aware system abstractions
and, on the other hand, cares a great deal for easily reusable implementations of these abstractions.
The latter aspect becomes more and more important as embedded systems technology is faced with an innovation
cycle decreasing in length. Software for embedded systems needs to be designed for variability, and this
is in particular true for the operating systems of this domain. The paper discusses dimensions of variability
that need to be considered in the development of embedded operating systems and presents approaches that
aid construction and maintenance of evolutionary operating systems.
CR subject classification C.3; D.2.11; D.2.13; D.4.7 相似文献
944.
945.
946.
947.
The AIDS Library evolved out of consumer health activism in response to the need for the latest HIV information, materials, and technology. In 1998, staff implemented a microcomputer-based integrated automated library system with Web publishing capability to link catalogs, databases of Philadelphia regional services, online publications, and fact sheets. The Web site, , became "live" December 1, 1998. History leading to its development and future plans are presented. 相似文献
948.
This study examines the perceived impacts of electronic government or e-government adoption on U.S. cities. This research conducted a survey of Texas and Florida city managers in the fall of 2005 to find out their opinions on the impact of e-government on their city government. The results indicated that e-government is having a positive impact on management, stakeholder involvement, needs and collaboration, and procurement in American cities. There are, however, concerns over spam or unsolicited e-mail and the ability of e-government to reduce the level of staffing. The results of this study imply that, according to city managers' perceptions, e-government adoption in American city governments is positively viewed as having an impact on their organizations and communities. 相似文献
949.
950.
Elke Achtert Christian B?hm Peer Kr?ger Peter Kunath Alexey Pryakhin Matthias Renz 《Informatik - Forschung und Entwicklung》2007,15(3):179-195
The reverse k-nearest neighbor (RkNN) problem, i.e. finding all objects in a data set the k-nearest
neighbors of which include a specified query object, has received increasing attention recently. Many
industrial and scientific applications call for solutions of the RkNN problem in arbitrary metric spaces
where the data objects are not Euclidean and only a metric distance function is given for specifying
object similarity. Usually, these applications need a solution for the generalized problem where the
value of k is not known in advance and may change from query to query. In addition, many applications
require a fast approximate answer of RkNN-queries. For these scenarios, it is important to generate
a fast answer with high recall. In this paper, we propose the first approach for efficient approximative
RkNN search in arbitrary metric spaces where the value of k is specified at query time. Our approach
uses the advantages of existing metric index structures but proposes to use an approximation of the
nearest-neighbor-distances in order to prune the search space. We show that our method scales significantly
better than existing non-approximative approaches while producing an approximation of the true query
result with a high recall. 相似文献