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71.
Piper Megan E.; Piasecki Thomas M.; Federman E. Belle; Bolt Daniel M.; Smith Stevens S.; Fiore Michael C.; Baker Timothy B. 《Canadian Metallurgical Quarterly》2004,72(2):139
The dependence construct fills an important explanatory role in motivational accounts of smoking and relapse. Frequently used measures of dependence are either atheoretical or grounded in a unidimensional model of physical dependence. This research creates a multidimensional measure of dependence that is based on theoretically grounded motives for drug use and is intended to reflect mechanisms underlying dependence. Data collected from a large sample of smokers (N = 775) indicated that all 13 subscales of the Wisconsin Inventory of Smoking Dependence Motives (WISDM-68) have acceptable internal consistency, are differentially present across levels of smoking heaviness, and have a multidimensional structure. Validity analyses indicated the WISDM-68 subscales are significantly related to dependence criteria such as smoking heaviness and to 4th edition Diagnostic and Statistical Manual of Mental Disorders symptoms of dependence and relapse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
A conventional way to analyze item responses in multiple tests is to apply unidimensional item response models separately, one test at a time. This unidimensional approach, which ignores the correlations between latent traits, yields imprecise measures when tests are short. To resolve this problem, one can use multidimensional item response models that use correlations between latent traits to improve measurement precision of individual latent traits. The improvements are demonstrated using 2 empirical examples. It appears that the multidimensional approach improves measurement precision substantially, especially when tests are short and the number of tests is large. To achieve the same measurement precision, the multidimensional approach needs less than half of the comparable items required for the unidimensional approach. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
The embedding of a small but expressive language of multidimensional functional programming in a well known and widely used language of object‐oriented programming leads to the combination of two radically different programming models. In this paper, we formally define the syntax and semantics of GLU?, which can be thought of as the multidimensional core of Lucid and GLU, and we describe its implementation as a language embedded in C++. With the aid of a few examples, we argue that the marriage of the two programming models is not only compatible and natural, but also that it produces a new and interesting hybrid language. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
74.
75.
This paper introduces the research progress of the State Key Laboratory of Information Security (SKLOIS) in China during 2002–2006.
This introduction covers four selected areas with each covering some selected research findings. The four selected areas are:
the fundamentals of cryptography; the design, analysis and testing of block cipher algorithms; the design and analysis of
security protocols based on computational intractability; authentication, authorization and their applications. 相似文献
76.
为提高工作流授权合理性验证的效率,增强对执行时任务指派的支持,提出了基于问题分解的工作流授权合理性验证方法。通过基于业务实例的工作流模型分解,将工作流授权合理性问题分解为业务实例、业务实例的并发任务集合、并发任务集合中任务的授权合理性问题,得到工作流授权合理性问题的与/或树表示。利用定义的合理指派路径及其串联操作,分析了工作流授权合理性问题与/或树节点的可解性。给出了基于与/或树搜索实现工作流授权合理性验证的算法,并分析了算法的复杂度及其输出的合理指派路径对工作流执行时任务指派的支持。在与/或树基础上,通过选择合适的启发函数,可以进一步提高验证效率,或快速生成适合问题需求的最佳解树。 相似文献
77.
Youngentob Steven L.; Johnson Brett A.; Leon Michael; Sheehe Paul R.; Kent Paul F. 《Canadian Metallurgical Quarterly》2006,120(6):1337
Odorants and their perceptions differ along multiple dimensions, requiring that a critical examination of any putative neural code directly assess the multidimensional nature of the encoding process. Previous work has examined simple, systematic odorant differences that, regardless of coding strategy, would be expected to produce simple, systematic predictions in neural and behavioral responses. In the present study, an odorant identification confusion matrix task that extracts precise quality relationships across odorants was used to determine whether spatially specific glomerular activity patterns predict perceptual quality relationships for odorants that cannot easily be classified a priori along a single chemical dimension. Multidimensional scaling (MDS) analysis of odorant pattern similarity measures derived from the comparison of [14C]-2-deoxyglucose glomerular activity pattern data yielded a two-dimensional odorant activity space that was highly significantly predictive of similarly obtained odorant perceptual spaces, uniformly across animals. These results strongly support the relevance of global spatial patterns in the olfactory bulb to the encoding of odor quality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
以国际上在标识、鉴别与授权标准方面已有的工作为基础,提出了我国电子认证与授权管理标准体系框架。 相似文献
79.
In this text we present``profile-based linguistic uniformity', a methoddesigned to compare language varieties on thebasis of a wide range of potentiallyheterogeneous linguistic variables. In manyrespects a parallel can be drawn with currentmethods in dialectometry (for an overview, see,Nerbonne and Heeringa, 2001; Heeringa, Nerbonneand Kleiweg, 2002): in both casesdissimilarities between varieties on the basisof individual variables are summarized inglobal dissimilarities, and a series oflanguage varieties are subsequently clusteredor charted using multivariate techniques suchas cluster analysis or multidimensionalscaling. This global similarity between themethods makes it possible to compare them andto investigate the implications of notabledifferences. In this text we specifically focuson, and defend one characteristic of ourmethodology, its profile-based nature. 相似文献
80.