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21.
With the aid of automated reasoning techniques, we show that all previously known short single axioms for odd exponent groups are special cases of one general schema. We also demonstrate how to convert the proofs generated by an automated reasoning system into proofs understandable by a human.Authors supported by NSF Grant DMS-9100665 相似文献
22.
Measuring knowledge transfer between fields of science 总被引:4,自引:2,他引:2
Rinia Ed J. van Leeuwen Thed N. Bruins Eppo E. W. van Vuren Hendrik G. van Raan Anthony F. J. 《Scientometrics》2002,54(3):347-362
In this paper we report on the results of an exploratory study of knowledge exchange between disciplines and subfields of
science, based on bibliometric methods. The goal of this analysis is twofold. Firstly, we consider knowledge exchange between
disciplines at a global level, by analysing cross-disciplinary citations in journal articles, based on the world publication
output in 1999. Among others a central position of the Basic Life Sciences within the Life Sciences and of Physics within
the Exact Sciences is shown. Limitations of analyses of interdisciplinary impact at the journal level are discussed. A second
topic is a discussion of measures which may be used to quantify the rate of knowledge transfer between fields and the importance
of work in a given field or for other disciplines. Two measures are applied, which appear to be proper indicators of impact
of research on other fields. These indicators of interdisciplinary impact may be applied at other institutional levels as
well.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
23.
Michael Anthony Puso Tod A. Laursen 《International journal for numerical methods in engineering》2002,54(8):1161-1194
In this work, a method is developed for smoothing three‐dimensional contact surfaces. The method can be applied to both regular and irregular meshes. The algorithm employs Gregory patches to interpolate finite element nodes and provide tangent plane continuity between adjacent patches. The resulting surface interpolation is used to calculate gaps and contact forces, in a variationally consistent way, such that contact forces due to normal and frictional contact vary smoothly as slave nodes transition from one patch to the next. This eliminates the ‘chatter’ which typically occurs in a standard contact algorithm when a slave node is situated near a master facet edge. The elimination of this chatter provides a significant improvement in convergence behaviour, which is illustrated by a number of numerical examples. Furthermore, smoothed surfaces also provide a more accurate representation of the actual surface, such that resulting stresses and forces can be more accurately computed with coarse meshes in many problems. This fact is also demonstrated by the numerical examples. Published in 2002 by John Wiley & Sons, Ltd. 相似文献
24.
Two studies examined the relationship between the content of a self-threat and the attractiveness of available self-affirmations (C. M. Steele, 1988). After self-threat was induced by means of a cognitive dissonance procedure, participants' choices for affirmations were examined in order to explore whether the attractiveness of a given affirmation depends on its relevance to the threatened domain of the self-concept. The authors hypothesized that when faced with a threat to a specific self-conception or standard, individuals may forego affirmations within the threatened self-concept domain in favor of affirmations of unrelated, compensatory domains. Both studies supported this hypothesis and further suggested that such selective self-affirmation can lead individuals to modify their self-concepts by identifying with self-aspects that justify dissonant behavior and by disidentifying with the standards that such behavior violates. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
25.
Merging uncertain information with semantic heterogeneity in XML 总被引:1,自引:1,他引:0
Semistructured information can be merged in a logic-based framework [6, 7]. This framework has been extended to deal with
uncertainty, in the form of probability values, degrees of beliefs, or necessity measures, associated with leaves (i.e. textentries)
in the XML documents [3]. In this paper we further extend this approach to modelling and merging uncertain information that
is defined at different levels of granularity of XML textentries, and to modelling and reasoning with XML documents that contain
semantically heterogeneous uncertain information on more complex elements in XML subtrees. We present the formal definitions
for modelling, propagating and merging semantically heterogeneous uncertain information and explain how they can be handled
using logic-based fusion techniques.
Anthony Hunter received a B.Sc. (1984) from the University of Bristol and an M.Sc. (1987) and Ph.D. (1992) from Imperial College, London.
He is currently a reader in the Department of Computer Science at University College London. His main research interests are:
Knowledge representation and reasoning, Analysing inconsistency, Argumentation, Default reasoning and Knowledge Fusion.
Weiru Liu is a senior lecturer at the School of Computer Science, Queen's University Belfast. She received her B.Sc. and M.Sc. degrees
in Computer Science from Jilin University, P.R China, and her Ph.D. degree in Artificial Intelligence from the University
of Edinburgh. Her main research interests include reasoning under uncertainty, knowledge representation and reasoning, uncertain
knowledge and information fusion, and knowledge discovery in databases. She has published over 50 journal and conference papers
in these areas. 相似文献
26.
Perkins Kenneth A.; Ciccocioppo Melinda; Jacobs Lynette; Doyle Todd; Caggiula Anthony 《Canadian Metallurgical Quarterly》2003,11(4):269
Nonpharmacological cues associated with drug intake may influence subjective and reinforcing effects of those drugs. Social drinkers (N = 80) participated in 2 sessions in which they rated and then consumed ad lib their preferred beer (with participants blind to brand). Visual and olfactory stimuli were obscured during 1 session (blocked) and not obscured during the other (unblocked). Dependent measures included ratings of "liking", "want another", and "desire to drink"; subjective mood; and ad lib beer consumption (reinforcement). Most ratings and ad lib consumption were lower during the blocked versus the unblocked condition. There were no interactions of blockade condition with sex and no effect of blockade on mood. These findings show that nonpharmacological stimuli associated with alcohol consumption influence alcohol's subjective and reinforcing effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
27.
We explain why the methods in Langridge, Hart and Crampin [Comput. Phys. Commun. 134 (2001) 78] suffice for the evaluation of the lattice sums entering the Madelung matrix describing multipole interactions in systems with one-dimensional translational periodicity. 相似文献
28.
OBJECTIVE: To determine the effect of area postrema AP on DOCA-salt induced hypertension in rat, with emphasis on renal hemodynamics. METHOD: Blood pressure, salt and water balances and renal hemodynamics were observed in AP ablated and sham-operated rats treated with DOCA-salt. RESULTS: In AP intact (API) rats, after one week of DOCA-salt treatment BP began elevating to statistical significance at the end of the second week (MAP 15.9 +/- 0.7 vs. 13.5 +/- 0.5 kPa), followed by a plateau period from the third to fifth week. In AP ablated (APX) rats, BP raised during the first week of DOCA-salt treatment. However, the elevation gradually disappeared and BP returned to baseline at the fifth week. Sodium balance study showed that DOCA-salt treatment induced significant sodium retention in API rat, while the sodium metabolism remained stable in APX group except in the first week. Basal renal hemodynamic parameters (GFR, RPF, UNaV, UV) were not changed at neither the beginning nor the end of the study. However, a small dose of hypertonic saline (7% NaCl 0.3 ml) injection caused a brisk rising of these four parameters in APX but not API group. CONCLUSION: AP plays an important role in normal salt and water metabolism and might be involved in pathogenesis of DOCA-salt hypertension through regulation for renal hemodynamics and body fluid homeostasis. 相似文献
29.
AR Hart B Jestico C Antill M Taylor JF Mayberry 《Canadian Metallurgical Quarterly》1996,110(4):247-249
We studied 100 healthy children looking for lactose malabsortion. We performed in all of them the lactose breath test. We found a 10% with lactose malabsortion. There was no correlation between lactose breath test and fecal reducing substances. 相似文献
30.
R Fitzpatrick J Dawson M Boulton J McLean G Hart M Brookes 《Canadian Metallurgical Quarterly》1994,44(379):80-82
BACKGROUND: Primary care has an important role to play in the prevention and management of the human immunodeficiency virus (HIV). It has been suggested that homosexual men experience a variety of problems in relation to primary care. AIM: As part of a larger study, it was decided to examine the extent to which a sample of homosexually active men experienced difficulties in general practice and whether they consulted their general practitioner for problems related to HIV or the acquired immune deficiency syndrome (AIDS). METHOD: Homosexual men were recruited for interview in 1991-92 from a variety of sources including genitourinary clinics and homosexual organizations. RESULTS: Of 623 men registered with a general practitioner 44% had not informed their general practitioner of their sexual orientation and 44% of the 77 men who were HIV antibody positive, as confirmed by the study, had not informed their general practitioner of this fact. Men who viewed their practice as unsympathetic towards homosexual men were less likely to have informed their general practitioner of their sexual orientation or HIV status. The majority of men (87%) nevertheless viewed primary care as an appropriate source of HIV/AIDS advice. CONCLUSION: There is considerable scope for improvement in the acceptability of general practice to homosexual men. 相似文献