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Schrifttumsübersicht. Herstellung synthetischer Olivine. Ermittlung des kristallchemischen Aufbaues. Thermo-Differentialanalyse. Eigenschaften der synthetischen Kalziumolivine. Auftreten von Kalziumolivinen in Sintern. Einfluß der Silikatphase auf die Sintereigenschaften. 相似文献
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Eugeniusz Zieniuk 《Engineering with Computers》2007,23(1):39-48
To create curves in computer graphics, we use, among others, B-splines since they make it possible to effectively produce
curves in a continuous way using a small number of de Boor’s control points. The properties of these curves have also been
used to define and create boundary geometry in boundary problems solving using parametric integral equations system (PIES).
PIES was applied for resolution 2D boundary-value problems described by Laplace’s equation. In this PIES, boundary geometry
is theoretically defined in its mathematical formalism, hence the numerical solution of the PIES requires no boundary discretization
(such as in BEM) and is simply reduced to the approximation of boundary functions. To solve this PIES a pseudospectral method
has been proposed and the results obtained were compared with both exact and numerical solutions. 相似文献
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The purpose of this study was to see whether 3 types of social support (enacted support, negative interaction, and anticipated support) are associated with change in meaning in life. Data from a nationwide longitudinal survey of older people suggested that greater anticipated support (i.e., the belief that others will provide assistance in the future if needed) is associated with a deeper sense of meaning over time. The same was true with respect to emotional support received from family members and close friends. In contrast, the findings revealed that, at least initially, negative interaction lowers an older person's sense of meaning in life. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Longitudinal factor structure of posttraumatic stress symptoms related to intimate partner violence.
Krause Elizabeth D.; Kaltman Stacey; Goodman Lisa A.; Dutton Mary Ann 《Canadian Metallurgical Quarterly》2007,19(2):165
Confirmatory factor analysis (CFA) studies have suggested that a model of posttraumatic stress disorder (PTSD) that is characterized by 4 factors is preferable to competing models. However, the composition of these 4 factors has varied across studies, with 1 model splitting avoidance and numbing symptoms (e.g., D. W. King, G. A. Leskin, L. A. King, & F. W. Weathers, 1998) and the other including a dysphoria factor that combines numbing and nonspecific hyperarousal symptoms (L. J. Simms, D. Watson, & B. N. Doebbeling, 2002). Using the PTSD Checklist (F. W. Weathers, B. T. Litz, D. S. Herman, J. A. Huska, & T. M. Keane, 1993) and CFA, the authors compared these models with competing models. A model of PTSD with 4 intercorrelated factors of Intrusions, Avoidance, Dysphoria, and Hyperarousal was found superior among 396 medical patients who screened positive for intimate partner violence (IPV) and 405 women seeking services for IPV. Structural invariance testing indicated that this 4-factor model remains stable across service setting and time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献