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151.
Elise Legghe Emmanuel Aragon Lénaïk Bélec André Margaillan Denis Melot 《Progress in Organic Coatings》2009
Epoxy adhesion to steel is known to be weakened by the presence of water. 相似文献
152.
We present a genetic algorithm for selecting centers to seed the popular k-means method for clustering. Using a novel crossover operator that exchanges neighboring centers, our GA identifies superior partitions using both benchmark and large simulated data sets. 相似文献
153.
An adaptive multimedia proxy is presented which provides (1) caching, (2) filtering, and (3) media gateway functionalities. The proxy
can perform media adaptation on its own, either relying on layered coding or using transcoding mainly in the decompressed
domain. A cost model is presented which incorporates user requirements, terminal capabilities, and video variations in one
formula. Based on this model, the proxy acts as a general broker of different user requirements and of different video variations. This is a first step towards What You Need is What You Get (WYNIWYG) video services, which deliver videos to users in exactly the quality they need and are willing to pay for. The
MPEG-7 and MPEG-21 standards enable this in an interoperable way. A detailed evaluation based on a series of simulation runs
is provided. 相似文献
154.
Weerts Elise M.; Fantegrossi William E.; Goodwin Amy K. 《Canadian Metallurgical Quarterly》2007,15(4):309
The use of nonhuman primates (NHP) is invaluable for drug abuse research. The laboratory animals most closely related to humans are NHP. The phylogeny, anatomy, physiology, neurochemistry, and behavior of NHP are more similar to humans than other laboratory species. There is now an extensive body of literature documenting the neuroanatomical, neurochemical, and neuropharmacological similarities between NHP and humans and the differences between NHP and other laboratory species in dopamine, norepinephrine, serotonin, opioid, and gamma aminobutyric acid systems. Comprehensive studies comparing pharmacokinetics in humans, monkeys, dogs, and rats have shown that data in monkeys are the most predictive of human pharmacokinetic parameters. The long life span and extended adolescent period for NHP permits intensive, long-term investigations and the use of within-subject experimental designs similar to those used in human laboratory studies. Within-subject designs require fewer subjects than standard between-group designs and permit the careful evaluation of individual differences. NHP have been used extensively in drug abuse research for over 40 years and have provided useful information on the behavioral processes associated with drug abuse and addiction as well as drug abuse liability in humans. This review focuses on important species differences between rodents and NHP and on the value of NHP in bridging the gap between rodents and humans to enhance the ability to generalize preclinical findings to human drug abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
155.
Ganzel Barbara; Casey B. J.; Glover Gary; Voss Henning U.; Temple Elise 《Canadian Metallurgical Quarterly》2007,7(2):227
Does trauma exposure have a long-term impact on the brain and behavior of healthy individuals? The authors used functional magnetic resonance imaging to assess the impact of proximity to the disaster of September 11, 2001, on amygdala function in 22 healthy adults. More than three years after the terrorist attacks, bilateral amygdala activity in response to viewing fearful faces compared to calm ones was higher in people who were within 1.5 miles of the World Trade Center on 9/11, relative to those who were living more than 200 miles away (all were living in the New York metropolitan area at time of scan). This activity mediated the relationship between group status and current symptoms of posttraumatic stress disorder. In turn, the effect of group status on both amygdala activation (fearful vs. calm faces) and current symptoms was statistically explained by time since worst trauma in lifetime and intensity of worst trauma, as indicated by reported symptoms at time of the trauma. These data are consistent with a model of heightened amygdala reactivity following high-intensity trauma exposure, with relatively slow recovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
156.
The competitive environment is giving rise to a paradigmatic transformation in how corporations organize and manage people. These transformations typically start with new outlying organizational units and progress slowly as innovations in management diffuse to older, more resistant organizations. Changes in these older units require the involvement of all stakeholders in designing an organization that will demand new behavior of them. Attitudes and new skills are developed through experience with new approaches to management, not education. Effective and rapid corporate transformation requires top management to develop a corporate context that will support diffusion. Champions who will lead change must be carefully placed to move change along, and they can benefit from the support of consultants skilled in both process and structural interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
157.
A qualitative test developed by Laszlo has been adapted to the quantitative determination of BHA. The determination is based
on measurement of the specific and sensitive color resulting from reaction of BHA with diazotized sulfanilic acid in alkaline
solution. The red-purple color, which is stable for long periods, has an absorption maximum at 535 mμ. Beer’s law is obeyed,
and a concentration range of 0.0001% to 0.01% BHA may be measured. The method requires careful adjustment of antioxidant-reagent
ratios for rapid and maximum color development, The optimum ratios, the effect of alcohol, and interfering substances are
diseussed.
The method, as described, also provides for an accurate specific determination of BHA in fats and oils even when other antioxidants
are present.
Journal Pager No. 184, American Meat Institute Foundation.
Presented at 50th Anniversary Meeting, American Oil Chemists’ Society, April 20–22, 1959, New Orleans, La.
Chemist in the Division for Inspection of Animal Products (D.I.P.O.A.) of the Ministry of Agriculture (Rio de Janeiro, Brazil)
and American Association of University Women Fellow at the American Meat Institute Foundation during 1958–59. 相似文献
158.
A numerical quadrature algorithm is developed, for integrands which may exhibit some kind of singular behaviour within the finite of infinite integration range. Using the automatical FORTRAN IV integration program, one should provide the abscissae the function is not “smooth” at. The quadrature formula has been obtained by applying the trapezoidal rule after transformation of the integrand. Standing severe tests which were based on the test functions of Casaletto et al. and on Kahaner's sample set, the integration scheme turned out to be of a remarkable reliability, efficiency and accuracy. 相似文献
159.
A method of treating data acquired with the planar laser‐induced fluorescence technique has been developed to visualize the topology of two‐dimensional concentration fields and to describe the dynamics of the coherent mixing structures identified. This method is based on a conditional binary transformation of the local concentration data, combined with a joint probability calculation. The methodology has been used to investigate the mixing in a stirred tank, at two injection port locations (in the bulk and in the impeller stream region). With bulk injection, a “folding phenomenon” of the coherent mixing structure was detected. Away from this port, large‐scale spatially periodic motion was identified, with a characteristic time of oscillation of the order of 2 to 3 s. With injection in the impeller stream region, no spatial instabilities of the coherent structure were detected. Local oscillations of the coherent mixing structure were found both on short and long time‐scales (i.e., ?1 and ?80 s). 相似文献
160.
Shadows of the Past in International Cooperation: Collaboration Profiles of the Top Five Producers of Science 总被引:6,自引:0,他引:6
This article aims at a characterization of the cooperation behavior among five large scientific countries (France, Germany, Japan, United Kingdom and United States of America) from 1986 to 1996. It looks at the cooperation profiles of these countries using classical measures such as the Probabilistic Affinity. The results show the major influence which historical, cultural and linguistic proximities may have on patterns of cooperation, with few changes over the period of time studied.A lack of specific affinities among the three largest European countries is revealed, and this contrasts with the strong linkage demonstrated between United States and Japan. The ensuing discussion raises some questions as to the process of Europeanization in science. The intensity of bilateral cooperation linkages is then studied with regard to field specialization by country, and this analysis yields no general patterns at the scale studied. Specific bilateral behaviors are also analyzed. 相似文献