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101.
102.
Lahey Benjamin B.; Loeber Rolf; Burke Jeffrey D.; Applegate Brooks 《Canadian Metallurgical Quarterly》2005,73(3):389
It is essential to identify childhood predictors of adult antisocial personality disorder (APD) to target early prevention. It has variously been hypothesized that APD is predicted by childhood conduct disorder (CD), attention-deficit/hyperactivity disorder (ADHD), or both disorders. To test these competing hypotheses, the authors used data from a single childhood diagnostic assessment of 163 clinic-referred boys to predict future APD during early adulthood. Childhood Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) CD, but not ADHD, significantly predicted the boys' subsequent APD. An interaction between socioeconomic status (SES) and CD indicated that CD predicted APD only in lower SES families, however. Among children who met criteria for CD, their number of covert but not overt CD symptoms improved prediction of future APD, controlling for SES. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Gump Brooks B.; Reihman Jacki; Stewart Paul; Lonky Ed; Darvill Tom 《Canadian Metallurgical Quarterly》2005,24(6):594
A number of studies have considered whether background stress affects cardiovascular responses to acute stress tasks. The present study considers the effect of a potent background stressor with a clear onset, namely the terrorist attacks on September 11, 2001. Specifically, the authors investigated differences among 9.5-year-old children tested before (N = 30) and then following (N = 20) the 9/11 attacks. In addition, a majority of these children (N = 37) were retested approximately 1 year later (i.e., before and after 9/11/2002). Children tested directly following 9/11/2001 exhibited significantly greater stroke volume and cardiac output responses to acute stress tasks compared with their responses 1 year later, and this change in reactivity differed significantly from the change in reactivity exhibited by children tested before 9/11/2001 and again 1 year later. These results suggest that a potent background stressor can temporarily heighten some children's cardiovascular responses to subsequent acute stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Christopher H. Brooks Edmund H. Durfee 《Autonomous Agents and Multi-Agent Systems》2003,7(1-2):145-170
We present congregating both as a metaphor for describing and modeling multiagent systems (MAS) and as a means for reducing coordination costs in large-scale MAS. When agents must search for other agents to interact with, congregations provide a way for agents to bias this search towards groups of agents that have tended to produce successful interactions in the past. This causes each agent's search problem to scale with the size of a congregation rather than the size of the population as a whole. In this paper, we present a formal model of a congregation and then apply Vidal and Durfee's CLRI framework [24] to the congregating problem. We apply congregating to the affinity group domain, and show that if agents are unable to describe congregations to each other, the problem of forming optimal congregations grows exponentially with the number of agents. The introduction of labelers provides a means of coordinating agent decisions, thereby reducing the problem's complexity. We then show how a structured label space can be exploited to simplify the labeler's decision problem and make the congregating problem linear in the number of labels. We then present experimental evidence demonstrating how congregating can be used to reduce agents' search costs, thereby allowing the system to scale up. We conclude with a comparison to other methods for coordinating multiagent behavior, particularly teams and coalitions. 相似文献
105.
106.
Brown GG Dian BC Douglass KO Geyer SM Shipman ST Pate BH 《The Review of scientific instruments》2008,79(5):053103
Designs for a broadband chirped pulse Fourier transform microwave (CP-FTMW) spectrometer are presented. The spectrometer is capable of measuring the 7-18 GHz region of a rotational spectrum in a single data acquisition. One design uses a 4.2 Gsampless arbitrary waveform generator (AWG) to produce a 1 mus duration chirped pulse with a linear frequency sweep of 1.375 GHz. This pulse is sent through a microwave circuit to multiply the bandwidth of the pulse by a factor of 8 and upconvert it to the 7.5-18.5 GHz range. The chirped pulse is amplified by a traveling wave tube amplifier and broadcast inside the spectrometer by using a double ridge standard gain horn antenna. The broadband molecular free induction decay (FID) is received by a second horn antenna, downconverted, and digitized by a 40 Gsampless (12 GHz hardware bandwidth) digital oscilloscope. The second design uses a simplified pulse generation and FID detection scheme, employing current state-of-the-art high-speed digital electronics. In this spectrometer, a chirped pulse with 12 GHz of bandwidth is directly generated by using a 20 Gsampless AWG and upconverted in a single step with an ultrabroadband mixer. The amplified molecular emission is directly detected by using a 50 Gsampless digital oscilloscope with 18 GHz bandwidth. In both designs, fast Fourier transform of the FID produces the frequency domain rotational spectrum in the 7-18 GHz range. The performance of the CP-FTMW spectrometer is compared to a Balle-Flygare-type cavity-FTMW spectrometer. The CP-FTMW spectrometer produces an equal sensitivity spectrum with a factor of 40 reduction in measurement time and a reduction in sample consumption by a factor of 20. The CP-FTMW spectrometer also displays good intensity accuracy for both sample number density and rotational transition moment. Strategies to reduce the CP-FTMW measurement time by another factor of 90 while simultaneously reducing the sample consumption by a factor of 30 are demonstrated. 相似文献
107.
专家系统是人工智能的一个分支,是一种模拟专家决策能力的计算机系统,知识库是系统的重要组成部分,是系统的核心。本文结合纺织工艺设计及管理专家系统介绍了基于知识的专家系统的概念和结构,对系统中知识的获取、存储方式予以说明.并对其知识的表示方法加以阐述。 相似文献
108.
109.
A recently proposed argument to explain the improved performance of the eight-point algorithm that results from using normalized
data (Chojnacki, W., et al. in IEEE Trans. Pattern Anal. Mach. Intell. 25(9):1172–1177, 2003) relies upon adoption of a certain model for statistical data distribution. Under this model, the cost function that underlies
the algorithm operating on the normalized data is statistically more advantageous than the cost function that underpins the
algorithm using unnormalized data. Here we extend this explanation by introducing a more refined, structured model for data
distribution. Under the extended model, the normalized eight-point algorithm turns out to be approximately consistent in a
statistical sense. The proposed extension provides a link between the existing statistical rationalization of the normalized
eight-point algorithm and the approach of Mühlich and Mester for enhancing total least squares estimation methods via equilibration.
The paper forms part of a wider effort to rationalize and interrelate foundational methods in vision parameter estimation. 相似文献
110.
PW Roelvink A Lizonova JG Lee Y Li JM Bergelson RW Finberg DE Brough I Kovesdi TJ Wickham 《Canadian Metallurgical Quarterly》1998,72(10):7909-7915
Attachment of an adenovirus (Ad) to a cell is mediated by the capsid fiber protein. To date, only the cellular fiber receptor for subgroup C serotypes 2 and 5, the so-called coxsackievirus-adenovirus receptor (CAR) protein, has been identified and cloned. Previous data suggested that the fiber of the subgroup D serotype Ad9 also recognizes CAR, since Ad9 and Ad2 fiber knobs cross-blocked each other's cellular binding. Recombinant fiber knobs and 3H-labeled Ad virions from serotypes representing all six subgroups (A to F) were used to determine whether the knobs cross-blocked the binding of virions from different subgroups. With the exception of subgroup B, all subgroup representatives cross-competed, suggesting that they use CAR as a cellular fiber receptor as well. This result was confirmed by showing that CAR, produced in a soluble recombinant form (sCAR), bound to nitrocellulose-immobilized virions from the different subgroups except subgroup B. Similar results were found for blotted fiber knob proteins. The subgroup F virus Ad41 has both short and long fibers, but only the long fiber bound sCAR. The sCAR protein blocked the attachment of all virus serotypes that bound CAR. Moreover, CHO cells expressing human CAR, in contrast to untransformed CHO cells, all specifically bound the sCAR-binding serotypes. We conclude therefore that Ad serotypes from subgroups A, C, D, E, and F all use CAR as a cellular fiber receptor. 相似文献