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111.
112.
Coastal water protection the Navy way 总被引:1,自引:0,他引:1
113.
Summary A context-free grammar form G defines a family of context-free grammars {ie397-01}(G). In this paper {ie397-02}(G) is extended to give the family of terminal context grammars {ie397-03}(G), which were introduced by Book [4]. It is shown that the families of languages defined by {ie397-04}(G) and {ie397-05}(G) are equal when G is an -free context-free grammar form. This generalizes the result of Book [4] for context-free grammars and underlines the usefulness of the notion of grammar forms in formal language theory.The work of the second author was carried out partially under a National Research Council of Canada Grant. No. A-7700 and partially under the auspices of the University of Karlsruhe 相似文献
114.
分辨率增强技术(RET)设计流程中聚集了各式各样的点工具和方法。当前对深亚波长可制造性(DFM)设计的要求迫使设计与制造行业必须建立十分密切的合作关系。同时也促使EDA行业提供一种平台,以促进这些行业间的密切交流。合理利用这一平台将会对产能和品质产生直接的影响。 相似文献
115.
Lau Anna S.; McCabe Kristen M.; Yeh May; Garland Ann F.; Wood Patricia A.; Hough Richard L. 《Canadian Metallurgical Quarterly》2005,19(3):367
The authors tested the acculturation gap-distress hypothesis by examining whether parent-adolescent acculturation gaps were associated with greater conflict and youth conduct problems among 260 high-risk Mexican American families. The authors operationalized acculturation gaps in 2 ways: parent-youth mismatches in acculturation style, and parent-youth discrepancies in acculturation toward both mainstream and heritage cultures. Acculturation gaps were common, but results of hierarchical regression analyses indicated that parent-youth discrepancies in acculturation toward mainstream and heritage cultures were not related to increased conflict or youth conduct problems. Conduct problems were no higher in families in which the adolescent was more aligned with mainstream culture than the parent. Unexpectedly, the authors found more youth conduct problems in families in which the youth was more aligned with traditional culture than the parent. The results call into question the assumption that the more rapid acculturation of adolescents to American culture inevitably leads to distress in minority families. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
116.
Wood Stacey; Busemeyer Jerome; Koling Andreas; Cox Cathy R.; Davis Hasker 《Canadian Metallurgical Quarterly》2005,20(2):220
Older adults process emotional information differently than younger adults and may demonstrate less of a negativity bias on cognitive tasks. The Iowa Gambling Task designed by A. Bechara, H. Damasio, D. Tranel, and A. R. Damasio (1997) has been used to examine the integration of emotion and cognition in a risky-choice decision task and may give insight into differences in the decision-making strategies in younger and older adults. Eighty-eight younger adults (18-34 years) and 67 older adults (65-88 years) completed the Iowa Gambling Task. Using a theoretical decomposition of the task designed by J. R. Busemeyer and J. C. Stout (2002), the authors found that both groups were successful at solving the task but used very different strategies that reflected each group's strength. For younger adults, that strength was learning and memory. For older adults, that strength was an accurate representation of wins and losses (valence). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
117.
The Unified Problem-Solving Method
Development Language UPML 总被引:2,自引:1,他引:2
118.
119.
The Naval Surface Warfare Center, Indian Head Division (NSWCIHD) is applying microelectromechanical system (MEMS) technology
to underwater weapon Safety and Arming (S&A) system development. MEMS technology provides an opportunity to develop a miniaturized
S&A system that is more sophisticated with improved safety and reliability at a lower cost compared to current systems. An
S&A system prevents premature initiation of the weapon while reliably ensuring initiation at the appropriate time. An S&A
system uses multiple sensors and devices. In comparison with other weapon S&A systems, a critical aspect of underwater weapon
S&A systems is the mechanical interlock system utilizing actuators and mechanical sensors. This paper describes the design,
development and fabrication of S&A SLIGA device prototypes and of a SLIGA based S&A system. NSWCIHD worked with members of
the HI-MEMS Alliance during design, development and fabrication. Advancements achieved by the HI-MEMS Alliance and SLIGA S&A
design issues are discussed.
Received: 25 August 1997/Accepted: 10 September 1997 相似文献
120.
T. W. Tsuei R. L. Wood C. Khan Malek M. M. Donnelly R. B. Fair 《Microsystem Technologies》1998,4(4):201-204
A method for creating angled structures for use in microvalve devices applicable to control of liquid flow is presented.
This technique utilizes a modified LIGA process with successive angled and rotated exposures into free standing acrylic sheets
to form a tapered valve seat structure. These valve seats are integrated with bulk micromachined silicon diaphragms and tapered
PMMA valve bosses to complete the microvalve. The long term goal of this research effort is to develop a normally-closed,
low power, microfabricated valve for use in an implantable drug delivery system. This paper reports on the design and fabrication
of microvalves using off-axis LIGA exposures. Flow testing and fluid handling characterization results are also presented.
Received: 25 August 1997 Accepted: 22 October 1997 相似文献