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991.
Catherine O. Bendure 《Information Systems Management》1991,8(4):50-56
Computer-aided software engineering (CASE) methodology and tools play an important role in the development of information systems and in the future direction of CASE. The amount of available information on this topic can be overwhelming. This article presents guidelines on selecting tools and a methodology based on the experience of the systems development team at Howard Hughes Medical Institute (HHMI), where CASE has been successfully implemented. 相似文献
992.
Schmidt Louis A.; Cote Kimberly A ; Santesso Diane L.; Milner Catherine E. 《Canadian Metallurgical Quarterly》2003,3(4):401
Electroencephalogram (EEG) alpha (8-12 Hz) asymmetries were collected from the mid-frontal and central regions during presleep wakefulness and Stage 1, Stage 2, and rapid eye movement (REM) sleep in 11 healthy right-handed participants who were free of psychiatric, neurological, and sleep problems. The authors found significant correlations between presleep wakefulness and different stages of sleep in the frontal, but not central, EEG alpha asymmetry measure. The strongest correlation was between presleep waking and REM sleep, replicating and extending relation earlier work to a normal population. The high degree of association between presleep waking and REM sleep may be a result of high cortical activation common to these states and may reflect a predisposition to different styles of emotional reactivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Kay Leslie M.; Lowry Catherine A.; Jacobs Heather A. 《Canadian Metallurgical Quarterly》2003,117(5):1108
Odor mixture perception can be configural (the mixture is qualitatively different from the components) or elemental (the components are recognizable). Some have argued that configural properties are dependent on chemical similarity and possible overlap at the receptor level. The authors show that a binary mixture in which both components activate the same receptor (17) has a configural odor, whereas a mixture that suppresses overlap has elemental odor properties. Rats trained to recognize mixtures of citronellal and octanal (strong 17 agonists) in many ratios rarely recognize the components, supporting configural representation of the odor mixture. However, when trained to recognize mixtures of citral (partial 17 agonist, inhibitor) and octanal, rats recognize 1 or both components over a wide range of ratios. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
This research extends previous work indicating that individuals are more effective at regulating their behavior when they are in goal-congruent contexts by examining whether individuals particularly need concrete goal-relevant situational affordances once they are in these broadly affirming contexts. Specifically, the authors explore this issue by using the broad context of steady dating relationships (i.e., intimacy-relevant contexts), and considering the role of both intimacy goals and intimacy-affording daily life situations in producing relationship satisfaction and maintenance over time. Results indicate that those with a strong focus on intimacy experience considerable relationship satisfaction regardless of whether they spend time in daily life situations that facilitate intimacy, whereas those without such a focus depend for satisfaction on the presence of intimacy-conducive situations (e.g., time alone with one's partner, or social support from one's partner). Discussion focuses on the theoretical implications of these findings for the Person x Situation literature. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Studied cooperation from a group process perspective within the free play of children aged 2, 3, and 4 yrs. 72 children were distributed among 12 groups, with 3 boys and 3 girls in each group and 4 groups in each age. Two 30-min sessions were videotaped for each group to assess dimensions of cooperation such as the number of children in each subgroup, kind of play, and type of activity. Observational analyses showed that cooperation is present at every age but may develop rapidly at certain ages and plateau at others. Furthermore, results suggest that group play is not the culmination of a linear developmental process. Modifications in quantity between the 2 youngest and the oldest group suggest a cooperation continuum of its own, with large variations between groups within each age group. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Catherine Everett 《Computer Fraud & Security》2004,2004(1):1-2
Without global legislation to combat spam, the problem will never be solved despite the fact that it is costs global businesses millions of dollars a year to tackle, believes the security industry. 相似文献
997.
Influence of Particle Shape and Surface Friction Variability on Response of Rod-Shaped Particulate Media 总被引:1,自引:0,他引:1
Catherine O’Sullivan Jonathan D. Bray Michael F. Riemer 《Canadian Metallurgical Quarterly》2002,128(11):1182-1192
Discrete element methods are important tools for the investigation of the mechanics of granular materials. In two dimensions, the reliability of these numerical approaches can be explored using physical tests on rod assemblies. This work highlights the importance of representing the actual distribution of rod shapes and surface friction in numerical simulations. The sensitivity of the response of hexagonally packed rods to minor changes in particle geometry and friction is investigated using a combination of laboratory tests and discrete element simulations. Laboratory test results highlight the influence of small variations in rod geometry on the global response, with the peak friction angle decreasing significantly as the standard deviation of the rod size distribution increased. Small changes in rod shape are also seen to be important. The numerical simulations indicate that the peak friction angle decreases as the standard deviation of the distribution of particle surface friction increases. This paper illustrates the way in which laboratory tests and numerical simulations can be used in a complementary manner to better understand the micromechanics of the response of granular materials. 相似文献
998.
999.
Catherine Everett 《Network Security》2004,2004(1):1
Emails that use social engineering techniques to manipulate people into opening infected attachments will become increasingly prevalent this year, after first rearing their ugly heads in 2003. 相似文献
1000.
Tomas Hudlicky Fan Rulin Toshiya Tsunoda Hector Luna Catherine Andersen John D. Price 《Israel journal of chemistry》1991,31(3):229-238
Bacterial oxygenation of halogenated aromatic compounds yields arene cis-diols of type 2 of high enantiomeric purity. Further oxygenation of these extremely versatile synthetic intermediates provides for stereo- and regioselective introduction of additional functionalities such as hydroxyl groups. Several rational methods of oxygenation (epoxidation, osmylation, singlet oxygen addition, and ozonolysis) are used to produce, in short synthetic routes, cyclitol derivatives of medicinal importance. Proper symmetry considerations lead to the development of enantiodivergent synthetic design of target compounds from a single enantiomer of a starting diol. These principles are illustrated on the short syntheses of (+)- and (-)-pinitol. Stereocontrolled oxidative transformation of diols of type 2 are exemplified in the synthesis of conduritol C and dihydroconduritol C. Full experimental details are provided for all compounds. A guide to the stereorational design of any stereoisomer of cyclohexane (poly)ols or carbohydrates is provided at the end of the paper. 相似文献