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排序方式: 共有1222条查询结果,搜索用时 281 毫秒
1.
Bill Robert Fleck Martin Troya Javier Mayerhofer Tanja Wimmer Manuel 《Software and Systems Modeling》2019,18(2):1017-1046
Software and Systems Modeling - Many model transformation scenarios require flexible execution strategies as they should produce models with the highest possible quality. At the same time,... 相似文献
2.
We consider a language of operations which pass parameters by means of a stack. An algebra over the set of type signatures is introduced, which allows the type signature of a program to be obtained from the type signatures of its constituent operations.Although the theories apply in principle to any stack based language, they have been evolved with particular regard to the proposed ANSI Standard Forth language, which is currently implemented in a type free manner. We hope this work will stimulate an interest in Forth amongst those applying algebraic techniques in software engineering, and we hope to lay the theoretical foundations for implementing practical type checkers to support Forth. 相似文献
3.
高性能纺织品整理方法及其应用 总被引:1,自引:0,他引:1
1 加工方法1 1 涂层纺织品的涂层可在多种设备上完成 ,其中最常用的是使用刮刀、辊筒、凹辊、粘辊和背辊。用于生产给定的最终产品时 ,每一种设备都有其优缺点 ,所以在选择时 ,我们应该对以下几点进行认真考虑 :纺织品的性质 ;涂层剂的流变性及其他性质 ;涂层剂是泡沫型的还是浆料型的 ;涂层剂在常温下还是在热熔条件下使用。另外 ,非常值得我们考虑的还有涂层剂的用量 ,以及涂层剂是用在织物的表面 ,还是尽量充满到织物结构内。所有这些都要由最终产品的性质及所要求具有的特种功能来确定。当前 ,除了涂层剂及织物的普通性能外 ,人们还… 相似文献
4.
Bill Woodruff 《电子设计技术》2005,12(1):136-136,138-139
较低的速度通常不能算是创新,但在10 Gbps以太网的领域内,两种“低速”互连标准,即LX4和CX4,正在降低实现成本,并实现新的应用。 相似文献
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BillMachrone 《个人电脑》2003,9(9):144-144
我已经看见了未来。它充满耀眼的光芒。这种特殊的未来的具体体现就是由Lumileds生产并打上Luxeon的品牌铛售的高亮度发光二极管,该公司把一些采用了最新技术的样机带到了我们的办公室,这给我们留下了深刻印象。 相似文献
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8.
Different forms of generativity in the writings of E. H. Erikson (1950/1963) and J. Kotre (1984) were related to agentic and communal motives in a sample of young adults (M?=?28 yrs old). For women, the power motive related to parenting, whereas the achievement motive was associated with forms of generative expression outside of the household. The opposite pattern of achievement and power motive relationships was found for men, although in a weaker form. The affiliation–intimacy motive, on the other hand, related both to women's parenting and societal concerns. Differences in expectations and opportunities for young men and women may account for these gender differences. The results for women support D. P. McAdams's (1988) suggestions that agency and communion are important for understanding generativity. In addition, the results provide evidence that people begin to grapple with generative issues as young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Xing Gu Shariar Sabuktagin Ali Teke Daniel Johnstone Hadis Morkoç Bill Nemeth Jeff Nause 《Journal of Materials Science: Materials in Electronics》2004,15(6):373-378
ZnO is a highly efficient photon emitter, and has optical and piezoelectric properties that are attractive for a variety of applications in sensors and potentially optoelectronic devices such as emitters. Due to its identical stacking order and close lattice match to GaN, it is also being developed as a substrate material for GaN epitaxy. However, the surface finish of the ZnO is such that much of the damage induced by sawing and follow up mechanical polishing remains. We developed a thermal treatment method to eliminate surface damage on the 0 face of ZnO (0 0 0 1) to prepare it for epitaxial growth. Atomic force microscopy images of ZnO (0 0 0 1) annealed at 1050 °C for 3 h etc. show that residual scratches from mechanical polishing are removed and atomically flat, terrace-like surfaces are attained. In addition, low-temperature photoluminescence and high-resolution X-ray diffraction measurements have been employed to investigate the effect of annealing on ZnO substrates. 相似文献
10.
Crystallization of Polymer-Derived Silicon Carbonitride at 1873 K under Nitrogen Overpressure 总被引:1,自引:0,他引:1
Martin Friess Joachim Bill Jerzy Golczewski re Zimmermann Fritz Aldinger Ralf Riedel Rishi Raj 《Journal of the American Ceramic Society》2002,85(10):2587-2589
The chemical stability of an amorphous silicon carbonitride ceramic, having the composition 0.57SiC·0.43Si3 N4 ·0.49C is studied as a function of nitrogen overpressure at 1873 K. The ceramic suffers a weight loss at p N2 < 3.5 bar (1 bar = 100 kPa), does not show a weight change from 3.5 to 11 bar, and gains weight above 11 bar. The structure of the ceramic changes with pressure: it is crystalline from 1 to 6 bar, amorphous at ∼10 bar, and is crystalline above ∼10 bar. The weight-loss transition, at 3.5 bar, is in excellent agreement with the prediction from thermodynamic analysis when the activities of carbon, SiC, and Si3 N4 are set equal to those of the crystalline forms; this implies that the material crystallizes before decomposition. The amorphous to crystalline transition that occurs at ∼10 bar, and which is accompanied by weight gain, is likely to have taken place by a different mechanism. A nucleation and growth reaction with the atmospheric nitrogen is proposed as the likely mechanism. The supersaturation required to nucleate α-Si3 N4 crystals is calculated to be 30 kJ/mol. 相似文献