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71.
Blanchard Kimberly A.; Morgenstern Jon; Morgan Thomas J.; Lobouvie Erich W.; Bux Donald A. 《Canadian Metallurgical Quarterly》2003,17(4):328
Negative consequences are an important component of the substance use change process, yet no standardized measure exists to assess consequences of use. This study evaluated the psychometric properties of the Inventory of Drug Use Consequences, a self-report measure assessing drinking and drug use consequences. Participants (N=252) were assessed at entry into outpatient substance abuse treatment. Items loaded strongly on 1 factor, and internal consistency of the total scale was high. Fifteen items with the highest correlations with the total scale were chosen to represent the construct. The shortened measure exhibited good internal consistency, convergent and discriminant validity, and detected change over time and may be the measure of substance use consequences that is lacking in the field. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Treated was an anti-plane crack perpendicular to the interface of an exponential-type FGM strip bonded to another linear-type
FGM substrate with infinite thickness. Through Fourier integral transform, the problem was reduced as a Cauchy singular integral
equation, which was further solved numerically by the Lobatto–Chebyshev collocation method. Based on the numerical solution,
the effects of the geometrical and physical parameters on the stress intensity factor (SIF) were analyzed and the following
conclusions were obtained: (a) A notable discrepancy between the interface-perpendicular crack and the interfacial one is
that, to reduce the weak-discontinuity of interface or to make the interface micro-discontinuous will not necessarily decrease
the SIF of the former, but will surely decrease that of the latter. (b) When a crack tip is situated very near to the interface
(or free surface), its SIF will be high and totally dominated by the interface (or free surface). (c) To increase the stiffness
of the FGM on one side of the interface is beneficial to preventing the crack on the other side from growing toward the interface.
Besides, some practical suggestions were further given for material design in the field of composites. 相似文献
73.
Racial and ethnic identity (REI) measures are in danger of becoming conceptually meaningless because of evaluators' insistence that they conform to measurement models intended to assess unidimensional constructs, rather than the multidimensional constructs necessary to capture the complexity of internalized racial or cultural socialization. Some aspects of the intersection of REI theoretical constructs with research design and psychometric practices are discussed, and recommendations for more informed use of each are provided. A table that summarizes some psychometric techniques for analyzing multidimensional measures is provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
A statistical study of the particle shape and size of pure V2O5 and TiO2, and samples of coprecipitated V2O5---TiO2 catalysts with different V/Ti ratios, has been performed. They were also characterized by XRD, EDAX, SEM and XPS. The results showed that pure vanadium pentoxide is compose by large square or needle-shaped particles, while pure titanium dioxide has small and rounded ones. VTiO samples presented an area and shape, depending on the V/Ti ratio.
These results and the spectroscopical characterization conducted to a particle model of the catalysts. Those VOTi samples with high V/Ti ratio would have large V2O5 crystals acting as support of a V/TiO2 solid solution. In contrast, those samples with a low V/Ti ratio, would have the solid solution supporting vanadium pentoxide crystals. 相似文献
75.
用于疏通油水井的脉冲放电技术 总被引:1,自引:0,他引:1
评价了各种不同的解堵技术,指出冲击波解堵是一种很有发展前途的技术。介绍了液中脉冲放电产生冲击波的基本原理,并由此研制出了一套井下脉冲放电油水井处理设备样机。通过现场试验,表明用冲击波疏通油井能较好地解除油井污染,提高采收率。 相似文献
76.
混凝土面板堆石坝坝料开采爆破试验 总被引:5,自引:3,他引:2
介绍在某水电站进行的混凝土面板堆石坝坝料开采爆破试验的情况。试验突破了仅根据岩石坚固性系数选取单位炸药消耗量的传统习惯,结合岩体裂隙与风化程度确定单位炸药消耗量,并采取分段装药,严格控制各段装药量和炮孔堵塞长度等措施,取得了良好的爆破效果。 相似文献
77.
B. E. Rytsar 《Cybernetics and Systems Analysis》2007,43(2):192-207
The paper considers the set-theoretical approach to the joint decomposition of systems of Boolean functions of variables specified
in different representation forms. The approach is based on the method of q-partitions of conjuncterms and concept of decomposition
clones. Theorems on joint decomposition of a system of full and partial functions are formulated. The approach is illustrated
by examples.
Parts I and II of this article are published in No. 5 (2001) and No. 1 (2002).
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 39–58, March–April 2007. 相似文献
78.
The efficiency characteristics of multicast key distribution schemes based on (v, b, r, λ)-designs are investigated. The stability
and connectivity of such designs are estimated. These estimates generalize and enhance the well-known estimates for the efficiency
characteristics of multicast key distribution schemes based on incomplete block designs.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 100–111, May–June 2007. 相似文献
79.
摘要:本文对血管内皮细胞生长因子(VEGF)的结构、功能及生理作用,VEGFR的靶向抗肿瘤新生血管生成治疗,VEGF的PET示踪剂分类,采用18F标记的VEGFR酪氨酸激酶抑制剂类合成等几个方面做了简要叙述。 相似文献
80.