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991.
With increasing globalization, communication across language and cultural boundaries is becoming an essential requirement
of doing business, delivering education, and providing public services. Due to the considerable cost of human translation
services, only a small fraction of text documents and an even smaller percentage of spoken encounters, such as international
meetings and conferences, are translated, with most resorting to the use of a common language (e.g. English) or not taking
place at all. Technology may provide a potentially revolutionary way out if real-time, domain-independent, simultaneous speech
translation can be realized. In this paper, we present a simultaneous speech translation system based on statistical recognition
and translation technology. We discuss the technology, various system improvements and propose mechanisms for user-friendly
delivery of the result. Over extensive component and end-to-end system evaluations and comparisons with human translation
performance, we conclude that machines can already deliver comprehensible simultaneous translation output. Moreover, while
machine performance is affected by recognition errors (and thus can be improved), human performance is limited by the cognitive
challenge of performing the task in real time. 相似文献
992.
The development of autonomous mobile machines to perform useful tasks in real work environments is currently being impeded
by concerns over effectiveness, commercial viability and, above all, safety. This paper introduces a case study of a robotic
excavator to explore a series of issues around system development, navigation in unstructured environments, autonomous decision
making and changing the behaviour of autonomous machines to suit the prevailing demands of users. The adoption of the Real-Time
Control Systems (RCS) architecture (Albus, 1991) is proposed as a universal framework for the development of intelligent systems. In addition it is explained how the use
of Partially Observable Markov Decision Processes (POMDP) (Kaelbling et al., 1998) can form the basis of decision making in the face of uncertainty and how the technique can be effectively incorporated into
the RCS architecture. Particular emphasis is placed on ensuring that the resulting behaviour is both task effective and adequately
safe, and it is recognised that these two objectives may be in opposition and that the desired relative balance between them
may change. The concept of an autonomous system having “values” is introduced through the use of utility theory. Limited simulation
results of experiments are reported which demonstrate that these techniques can create intelligent systems capable of modifying
their behaviour to exhibit either ‘safety conscious’ or ‘task achieving’ personalities. 相似文献
993.
Anastassios Pouris 《Scientometrics》2007,70(3):541-553
This article reports the findings of a scientometric analysis of nanoscale research in South Africa during the period 2000–2005.
The ISI databases were identified as the most appropriate information platform for the objectives of the investigation and
have been interrogated for the identification of South African authors publishing in the field.
The article identifies trends over time, major institutional contributors, journals in which South African authors publish
their research, international collaborators and performance in comparison to four comparator countries (India, Brazil, South
Korea and Australia). The major findings of the investigation are as follows: nanoscale research in South Africa is driven
by individual researchers interests up to date and it is in its early stages of development; the country’s nanoscale research
is below what would one expect in light of its overall publication output; the country’s nano-research is distributed to a
number of Universities with subcritical concentration of researchers. 相似文献
994.
This paper describe an approach for improving the data quality of corporate sources when databases are used for bibliometric
purposes. Research management relies on bibliographic databases and citation index systems as analytical tools, yet the raw
resources for bibliometric studies are plagued by a lack of consistency in fied formatting for institution data. The present
contribution puts forth a Natural Language Processing (NLP)-oriented method for the identification of the structures guiding
corporate data and their mapping into a standardized format. The proposed unification process is based on the definition of
address patterns and the ensuing application of Enhanced Finite-State Transducers (E-FST). Our procedure was tested on address
formats downloaded from the INSPEC, MEDLINE and CAB Abstracts. The results demonstrate the helpfulness of the method as long
as close control of errors is exercised as far as the formats to be unified. The computational efficacy of the model is noteworthy,
due to the fact that it is firmly guided by the definition of data in the application domain. 相似文献
995.
Bibliometric analysis of tsunami research 总被引:3,自引:0,他引:3
The use of the bibilometric analytical technique for examining tsunami research does not exist in the literature. The objective
of the study was to perform a bibliometric analysis of all tsunami-related publications in the Science Citation Index (SCI).
Analyzed parameters included document type, language of publication, publication output, authorship, publication patterns,
distribution of subject category, distribution of author keywords, country of publication, most-frequently cited article,
and document distribution after the Indonesia tsunami. The US and Japan produced 53% of the total output where the seven major
industrial countries accounted for the majority of the total production. English was the dominant language, comprising 95%
of articles. A simulation model was applied to describe the relationship between the number of authors and the number of articles,
the number of journals and the number of articles, and the percentage of total articles and the number of times a certain
keyword was used. Moreover the tsunami publication patterns in the first 8 months after the Indonesia tsunami occurred on
26 December 2004 indicated a high percentage of non-article publications and more documents being published in journals with
higher impact factors. 相似文献
996.
997.
Initial stages of surface erosion have been studied for NaCl and LiF single crystals bombarded by Ar+ ions with 20 keV. For irradiation with doses D=1010-1011 ions/cm2, exoelectron emission has been used, whereas for higher doses, we have used electron microscopy. Two stages of initial surface erosion have been identified; for small doses, there is slow development of atomic-scale roughening, which reaches its peak when areas damaged by closest incident ions start to overlap, and then, beginning with D=1016 ions/cm2, there is rapid etching, deep into the crystal, followed by the emergence of secondary microscopic structure, i.e. caverns, concentric closed steps and terraces. Ion-induced surface structure of alkali halide crystals has been shown to depend strongly on the presence of foreign particles on the surface, as well as on segregation. Topography of thin carbon films and some metals have been discussed. 相似文献
998.
Remigiusz Sapa 《Scientometrics》2007,71(3):473-493
This article reports findings from the study of the international contribution to the system of library and information science
communication in Poland in the years 2003–2005. The sample consists of articles published both in selected journals and collective
works. Two important dimensions determining the internationalization of local scholarly communication are considered: direct
contribution (foreign authors’ articles and papers and their translations published in Poland) and indirect contribution (citedness
of foreign authors’ documents in articles and papers published in Poland). Bibliographic data about the geographical distribution
and affiliation of foreign authors are gathered and analyzed. Furthermore, the findings of citation analysis are presented
to determine the percentage share of citations received by foreign documents as well as to find out what is the structure
of such citations regarding the language and form, which thematic areas are most replete with such citations and which foreign
journals are most cited in Poland. 相似文献
999.
Claude Robert Concepción S. Wilson Jean-François Gaudy Charles-Daniel Arreto 《Scientometrics》2007,73(2):231-256
During the 1974–2004 period, the sleep literature had quadrupled (2384 publications in 1974, and 9721 in 2004) while overall
scientific productivity had only doubled. The set of the seven most productive countries (USA, Japan, United Kingdom, Germany,
France, Canada and Italy) in sleep research, and the geographical region distribution remained stable over the three decades.
On the other hand several indicators appeared in the sleep research literature during the 1990s: the increasing productivity
of sleep researchers; the growing number of countries publishing on sleep; the continuous creation of sleep-focused journals;
the scattering of sleep publication among increasingly more scientific journals; the turnover among the leading journals;
and the emergence of new entities such as China, Turkey, and the European Union. 相似文献
1000.
Joachim Schummer 《Scientometrics》2007,70(3):669-692
Based on bibliometric methods, this paper describes the global institutionalization of nanotechnology research from the mid-1980s
to 2006. Owing to an extremely strong dynamics, the institutionalization of nanotechnology is likely to surpass those of major
disciplines in only a few years. A breakdown of the relative institutionalizations strengths by the main geographical regions,
countries, research sectors, disciplines, and institutional types provides a very diverse picture over the time period because
of different national science policies. The results allow a critical assessment of the different science policies based on
the relative institutionalizations strengths as well as the conclusion that the institutionalization process has run out of
control of individual governments who once induced the development. 相似文献