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排序方式: 共有1049条查询结果,搜索用时 15 毫秒
1.
SPEEK/cSMM membrane for simultaneous electricity generation and wastewater treatment in microbial fuel cell
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Industries in the US continue to lose ground in international competition. If IS is to help change that trend, it will have to become more creative. Creativity improvement programs are being introduced in other areas of the company— now is the time for IS organizations to follow suit. 相似文献
4.
Safron Adam; Barch Bennett; Bailey J. Michael; Gitelman Darren R.; Parrish Todd B.; Reber Paul J. 《Canadian Metallurgical Quarterly》2007,121(2):237
Men exhibit much higher levels of genital and subjective arousal to sexual stimuli containing their preferred sex than they do to stimuli containing only the nonpreferred sex. This study used event-related functional magnetic resonance imaging to investigate how this category-specific pattern would be reflected in the brains of homosexual (n = 11) and heterosexual (n = 11) men. Comparisons of activation to preferred sexual stimuli, nonpreferred sexual stimuli, and sports stimuli revealed large networks correlated with sexual arousal, spanning multiple cortical and subcortical areas. Both homosexual and heterosexual men exhibited category-specific arousal in brain activity. Within the amygdala, greater preference-related activity was observed in homosexual men, but it is unclear whether this is a cause or a consequence of their sexuality. In a subsequent analysis of regions hypothesized to support arousal, both participant groups demonstrated widespread increases in evoked activity for preferred stimuli. Aggregate data from these regions produced significant differences between stimulus types in 16 out of 22 participants. Significant activational differences matched reported sexual orientation in 15 of these 16 participants, representing an advance in psychophysiological measures of arousal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
ßBarrels are widespread and well-studied featuresof a great many protein structures. In this paper an unsuper-visedmethod for the detection of P-barrels is developed based ontechniques from graph theory. The hydrogen bonded connectivityof ß-sheets is derived using standard pattern recognitiontechniques and expressed as a graph. Barrels correspond to topologicalrings in these connectivity graphs and can thus be identifiedusing ring perception algorithms. Following from this, the characteristictopological structure of a barrel can be expressed using a novelform of reduced nomenclature that counts sequence separationsbetween successive members of the ring set These techniquesare tested by applying them to the detection of barrels in anon-redundant subset of the Brookhaven database. Results indicatethat topological rings do seem to correspond uniquely to ß-barrelsand that the technique, as implemented, finds the majority ofbarrels present in the dataset. 相似文献
6.
Flynn P.J. Jain A.K. 《IEEE transactions on pattern analysis and machine intelligence》1991,13(10):1066-1075
BONSAI, a model-based 3D object recognition system, is described. It identifies and localizes 3D objects in range images of one or more parts that have been designed on a computer-aided-design (CAD) system. Recognition is performed via constrained search of the interpretation tree, using unary and binary constraints (derived automatically from the CAD models) to prune the search space. Attention is focused on the recognition procedure, but the model-building, image acquisition, and segmentation procedures are also outlined. Experiments with over 200 images demonstrate that the constrained search approach to 3D object recognition has an accuracy comparable to that of previous systems 相似文献
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A Region Ensemble for 3-D Face Recognition 总被引:1,自引:0,他引:1
Faltemier T.C. Bowyer K.W. Flynn P.J. 《Information Forensics and Security, IEEE Transactions on》2008,3(1):62-73
In this paper, we introduce a new system for 3D face recognition based on the fusion of results from a committee of regions that have been independently matched. Experimental results demonstrate that using 28 small regions on the face allow for the highest level of 3D face recognition. Score-based fusion is performed on the individual region match scores and experimental results show that the Borda count and consensus voting methods yield higher performance than the standard sum, product, and min fusion rules. In addition, results are reported that demonstrate the robustness of our algorithm by simulating large holes and artifacts in images. To our knowledge, no other work has been published that uses a large number of 3D face regions for high-performance face matching. Rank one recognition rates of 97.2% and verification rates of 93.2% at a 0.1% false accept rate are reported and compared to other methods published on the face recognition grand challenge v2 data set. 相似文献
10.
E. Fay D. J. Flynn J. R. Lundehn P. J. Chapman R. D. Mason 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2007,17(3):61-77
Pflanzenschutzmittel müssen seit 1993 in den Mitgliedstaaten der Europ?ischen Gemeinschaft nach der Richtlinie 91/414/EWG
des Rates bewertet und zugelassen werden. Das Programm zur Bewertung von alten Wirkstoffen (welche vor Juli 1993 auf dem Markt
waren) beinhaltet mehrere Schritte und Stufen, die früher über einen Zeitraum von bis zu 10 Jahren zu bew?ltigen waren; heute
sind dafür jedoch 15 Jahre vorgesehen. Das Programm wurde seit 1996 von der Europ?ischen Kommission mit Unterstützung des
ECCO-Teams(European Community Co-Ordination) koordiniert. Das ECCO-Team bestand aus zwei Gruppen: eine im Pesticides Safety Directorate – PSD in York (Gro?britannien)
und eine im Bundesamt für Verbraucherschutz und Lebensmittelsicherheit (BVL) bzw. vor November 2002 in der Biologischen Bundesanstalt
für Land- und Forstwirtschaft in Braunschweig. Sie unterstüzten das Programm zur Bewertung von Wirkstoffen im Namen der Kommission
in technischer und administrativer Hinsicht und zeichneten sich insbesondere für das ECCO Peer Review Programm (Expertenprüfungen)
verantwortlich. Im November 2003 übernahm die Europ?ische Beh?rde für Lebensmittelsicherheit (EFSA) die Verantwortung für
die wissenschaftliche überprüfung der von den Mitgliedstaaten erstellten Bewertungen durch Experten. Das ECCO-Team leistete
jedoch weiterhin der Europ?ischen Kommission Unterstützung bei der Durchführung anderer Verfahrensaspekte, vor allem im Bereich
der Managementaufgaben der Europ?ischen Kommission. Insgesamt war das Programm au?erordentlich erfolgreich. Es wurden für
162 Wirkstoffen zwischen 1996 und 2003 der Inhalt der von den Mitgliedstaaten erstellten Bewertungsberichte durch eine Expertengruppe
diskutiert und füberprüft, was ma?geblich eine Entscheidungsfindung zur Akzeptabilitf?t dieser Wirkstoffe auf Gemeinschaftsebene
erm?glicht hat. 相似文献