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991.
992.
In this paper, we study the problem of implementing standard data structures on a hypercube multiprocessor. We present a technique for efficiently executing multiple independent search processes on a class of graphs called ordered h-level graphs. We show how this technique can be utilized to implement a segment tree on a hypercube, thereby obtaining O(long2n) time algorithms for solving the next element search problem, the trapezoidal composition problem, and the triangulation problem. 相似文献
993.
Blumenthal James A.; Sherwood Andrew; Gullette Elizabeth C. D.; Georgiades Anastasia; Tweedy Damon 《Canadian Metallurgical Quarterly》2002,70(3):569
Despite recent advances in the medical management of hypertension, chronically elevated blood pressure remains a major health problem in the United States, affecting almost 50 million Americans. It is widely recognized that lifestyle factors contribute to the development and maintenance of elevated blood pressure. This article critically reviews current approaches to the nonpharmacological treatment of high blood pressure and highlights outcome studies of exercise, weight loss and dietary modification, and stress management and relaxation therapies. Methodological issues in the assessment and treatment of hypertension are discussed, along with possible mechanisms by which lifestyle modification may reduce elevated blood pressure. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Steenbergh Timothy A.; Meyers Andrew W.; May Ryan K.; Whelan James P. 《Canadian Metallurgical Quarterly》2002,16(2):143
The Gamblers' Beliefs Questionnaire (GBQ) is a self-report measure of gamblers' cognitive distortions. GBQ test items were constructed on the basis of theory, empirical evidence, and expert review. Four hundred three adults completed the initial set of items, and 21 items werr selected to make up the final GBQ. The factor structure of the GBQ consisted of 2 closely related factors: Luck/Perseverance and Illusion of Control. The full scale showed good internal consistency (α?=?.92) and adequate test-retest reliability (r?=?.77). Problem and pathological gamblers scored higher than nonproblem gamblers on the GBQ and its factors. GBQ scores were moderately correlated with the duration of gambling sessions among problem and pathological gamblers, and there was no relationship between GBQ scores and social desirability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Gerald J Smith Ian J Miller Vincent Daniels Andrew J Smith 《Coloration Technology》1997,113(4):124-126
The possible stimulus to the dye industry in antiquity provided by the breeding of sheep with a white fleece is linked to the development of a colour vocabulary apparent in ancient texts. 相似文献
996.
Jeff T. M. De Hosson Wouter A. Soer Andrew M. Minor Zhiwei Shan Eric A. Stach S. A. Syed Asif Oden L. Warren 《Journal of Materials Science》2006,41(23):7704-7719
As a tribute to the scientific work of Professor David Brandon, this paper delineates the possibilities of utilizing in situ transmission electron microscopy to unravel dislocation-grain boundary interactions. In particular, we have focused on the deformation characteristics of Al–Mg films. To this end, in situ nanoindentation experiments have been conducted in TEM on ultrafine-grained Al and Al–Mg films with varying Mg contents. The observed propagation of dislocations is markedly different between Al and Al–Mg films, i.e. the presence of solute Mg results in solute drag, evidenced by a jerky-type dislocation motion with a mean jump distance that compares well to earlier theoretical and experimental results. It is proposed that this solute drag accounts for the difference between the load-controlled indentation responses of Al and Al–Mg alloys. In contrast to Al–Mg alloys, several yield excursions are observed during initial indentation of pure Al, which are commonly attributed to the collective motion of dislocations nucleated under the indenter. Displacement-controlled indentation does not result in a qualitative difference between Al and Al–Mg, which can be explained by the specific feedback characteristics providing a more sensitive detection of plastic instabilities and allowing the natural process of load relaxation to occur. The in situ indentation measurements confirm grain boundary motion as an important deformation mechanism in ultrafine-grained Al when it is subjected to a highly inhomogeneous stress field as produced by a Berkovich indenter. It is found that solute Mg effectively pins high-angle grain boundaries during such deformation. The mobility of low-angle boundaries is not affected by the presence of Mg.Special title: Advanced Materials and Characterization: Proceedings of the Brandon Symposium; Guest Editors: Wayne D. Kaplan and Srinivasa Ranganathan 相似文献
997.
The effects of methacrylic acid (MAA) on the physical properties of polymer made by emulsion copolymerization of butyl acrylate (BA) and MAA were examined. Emulsion polymerizations were performed with and without MAA and at temperatures of 0.1 and 50 °C, using redox initiation so that the radical flux was essentially independent of temperature. The presence of methacrylic acid had only a small effect on gel fraction and on molecular weight, but a profound effect on the film properties; changing the synthesis temperature was found to slightly alter the properties of the copolymer films. Latexes containing MAA formed much stronger films (from creep tests), and significantly increased tack and peel adhesion. This was attributed to intermolecular dipole-dipole interactions of the acid groups. Conductometric titration measurements revealed that the acid groups were predominantly located inside the latex particles, with only a small proportion in the aqueous phase and on the particle surface. Temperature was found not to affect significantly the partitioning of the acid groups in the latex. 相似文献
998.
Hardy David J.; Hinkin Charles H.; Levine Andrew J.; Castellon Steven A.; Lam Mona N. 《Canadian Metallurgical Quarterly》2006,20(3):355
Decision making was assessed using a laboratory gambling task in 67 adults with the Human Immunodeficiency Virus (HIV+) and in 19 HIV-seronegative (HIV-) control participants. Neurocognitive test performance across several domains was also analyzed to examine potential cognitive mechanisms of gambling task performance. As predicted, the HIV+ group performed worse on the gambling task, indicating greater risky decision making. Specifically, the HIV+ group selected more cards from the "risky" or disadvantageous deck that included relatively large payoffs but infrequent large penalties. The control group also selected such risky cards but quickly learned to avoid them. Exploratory analyses also indicated that in the HIV+ group, but not in the control group, gambling task performance was correlated with Stroop Interference performance and long delay free recall on the California Verbal Learning Test, suggesting the role of inhibitory processes and verbal memory in the poorer gambling task performance in HIV. These findings indicate the usefulness of the gambling task as a laboratory tool to examine risky decision making and cognition in the HIV population. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
The glass transition temperatures (Tgs) and proton conductivities of polyimides synthesized from naphthalene‐1,4,5,8‐tetracarboxylic dianhydride (NTDA), 2,2′‐benzidinedisulfonic acid (BDSA), 4,4′‐diaminodiphenylether‐2,2′‐disulfonic acid (ODADS), and non‐sulfonated diamine monomers have been predicted using molecular dynamics simulations. The specific volumes for two dry and four hydrated NTDA‐based polyimides were plotted versus temperatures above and below Tgs to obtain the glass transition temperatures. The simulation results suggest that the ODADS‐based polyimide membranes exhibit lower Tgs and thus better mechanical properties than the BDSA‐based polyimides, which may be attributed to the high mobility of backbones of ODADS as supported by the vectorial autocorrelation function (VACF) results of this study. In addition, comparison of the simulated Tgs for the dry and hydrated ODADS‐based polyimides has shown that water content in polyimides can affect their Tgs. The proton conductivities of a representative polyimide in both dry and hydrated conditions have been obtained from molecular dynamics simulations of the proton and hydronium ion diffusion. The simulated conductivity for the hydrated NTDA‐ODADS/BAPB cell is in reasonable agreement with the experimental value obtained from the AC impedance method. The relationship between the chemical composition, chain flexibility, and the glass transition and proton conduction of these NTDA‐based polyimides was explored on the basis of VACF and pair correlation function analysis. Copyright © 2006 Society of Chemical Industry 相似文献
1000.
Silverstein Steven M.; Hatashita-Wong Michi; Wilkniss Sandra; Bloch Andrew; Smith Thomas; Savitz Adam; McCarthy Richard; Friedman Michael; Terkelsen Ken 《Canadian Metallurgical Quarterly》2006,3(3):145
This article describes an intensive, inpatient behavioral rehabilitation program for patients with schizophrenia who have been considered "treatment-refractory" at state hospitals. The program is a public-private partnership involving state and private hospitals and community residence providers. The essential elements of this program are described, along with the conceptual and philosophical bases of its treatment and examples of staff behaviors critical to treatment success. Outcome data are then discussed to emphasize the point that when evidence-based psychological treatment is implemented with this population, outcomes can be positive in most cases, and therefore, the number of treatment-refractory patients is actually far less than is estimated on the basis of response to medication alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献