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141.
142.
In this paper we consider two performance modelling techniques from the perspectives of model construction, generation of
an underlying continuous time Markov process, and the potential for reduction in the Markov process. Such careful comparison
of modelling techniques allows us to appreciate the strengths and weaknesses of different approaches, and facilitates cross-fertilization
between them. In the present case we take a characteristic of one formalism, functional rates in Stochastic Automata Networks,
and introduce it to the other formalism, Performance Evaluation Process Algebra. We investigate the benefits of this cross-fertilization,
particularly from the perspectives of Markov process generation and reduction. 相似文献
143.
144.
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
145.
Talita Moreira de Oliveira Nilda de Fátima Ferreira Soares Rodrigo Magela Pereira Kátia de Freitas Fraga 《Packaging Technology and Science》2007,20(2):147-153
Conservation of food products depends on product quality and packaging suitability. The objective of this work was to develop and evaluate the antimicrobial efficiency of natamycin‐incorporated film in the production process of Gorgonzola cheese. It aims to optimize the production process and increase shelf‐life and food safety for the consumer. Films with different concentrations of natamycin were produced and tested in Gorgonzola cheeses to evaluate its efficiency against Penicillium roqueforti on the cheese surface. Films with 2 and 4% natamycin presented satisfactory results for fungus inhibition and the amount of natamycin released to the cheese was below that allowed by the legislation. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
146.
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
147.
148.
Grant Lewison 《Scientometrics》2007,72(3):439-458
This paper describes an analysis of coverage of the risks from agricultural and food genetically-modified organisms (GMOs)
from April 2002 to April 2004 in 14 news media from six countries (Canada, France, Germany, Spain, the UK and the USA) which
was conducted as part of a review for the European Commission of the management of risk communication. A total of 597 relevant
news articles were found and coded for their presentational tone, the types of risk (environmental, financial, health and
political, in that order), the organisms described (mainly maize, rape and beet crops), and the documents, people and organisations
cited. UK news media tended to be the most “scary” and Spanish ones the most “robust”. Articles quoting public perceptions,
non-governmental environmental organisations and politicians tended to emphasize the risks of GMOs; those quoting scientists
tended to downplay the risks and describe their potential benefits. Some suggestions for possible action by the European Commission
are put forward, such as the facilitation of contact between journalists and scientists, but it is recognized that for some
newspapers, their editorial wish to campaign will inevitably over-ride their reporters’ wish to present the truth. 相似文献
149.
This study examined why Websites were co-linked using Canadian university Websites as the test set. Pages that co-linked to
these university Websites were located using Yahool. A random sample of 859 co-linking pages (the page that initiated the
co-link) was retrieved and the contents of the page, as well as the context of the link, were manually examined to record
the following variables: language, country, type of Website, and the reasons for co-linking. The study found that in over
94% of cases, the two co-linked universities were related academically; many of these cases (38%) showed a relationship specifically
in teaching or research. This confirms results, from previous quantitative studies, that Web co-links can be a measure of
the similarity or relatedness of sites being co-linked and that Web co-link analysis can thus be used to study relationships
among linked Websites. 相似文献
150.