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41.
42.
The public information signs ( The term public information signs will be abbreviated to public signs in the following text.)in the urban areas not only offer convenience for people to move around, but also reflect the level of development and progress of those areas. It is essential to the creative development and uplifting of the New Costal Area (thereafter, NCA) to have a good understanding of its present situation with regard to its public signs, to discuss the related issues in the development, to work out a system that is up to international standard and develop its own standards in the course of implementing the national strategies on standardizing public signs. 相似文献
43.
The Humanitarian Engineering initiative, sponsored by the William and Flora Hewlett Foundation, at the Colorado School of Mines, is creating a program that will support engineering students in understanding their responsibility for solving community development problems that exist throughout the world. As part of this effort, data has been collected on faculty and student attitudes using the ‘Community Service Attitudes Scale,” developed and validated by Shiarella, McCarthy, and Tucker. During the fall 2004, 78 students and 34 faculty members responded to this instrument. Statistically significant differences were found between the attitudes of students and faculty, males and females, and among different age groupings with respect to service activities. A general finding was that faculty displayed better attitudes toward community service than the students. 相似文献
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P. R. Cetlin S. Yue J. J. Jonas T. M. Maccagno 《Metallurgical and Materials Transactions A》1993,24(7):1543-1553
Most laboratory simulations of hot rolling involve a scaling down of the strain rate from the much higher industrial levels.
This leads to slower softening between each rolling pass, for which corrections must be made. In the present work, torsion
testing simulations of “warm” rod rolling were conducted on a Ti-Nb interstitial-free (IF) steel at 840 °C and 770 °C(i.e., in the ferrite range). For this purpose, “strain rate corrected” interpass times were used, in addition to the more familiar
corrections for the stress. The results are compared with those obtained from simulations using uncorrected industrial interpass
times. At 840 °C, simulations using corrected interpass times led to high levels of softening between the stages of rolling,
thus triggering the reinitiation of cycles of dynamic recrystallization. The initially high stress level at the start of these
cycles was responsible for the large differences in the pass-to-pass mean flow stress behavior, compared with that observed
when using uncorrected industrial interpass times, or continuous deformations. The differences were much less pronounced at
770 °C, where the rate of softening is much slower than at 840 °C. Predictions for softening based on the Avrami equation
underestimated the softening observed using the continuous and uncorrected industrial interpass time schedules and overestimated
it for the corrected ones. The former is due to the occurrence of recovery, which is not addressed by the Avrami relation,
while the latter is due to the precipitation that takes place during the corrected (longer) interpass times. It was also found
that simulations using continuous deformations are applicable only if the interpass softening that would be expected using
the corrected interpass times does not exceed about 20 pct. 相似文献
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47.
首先建立缺陷空间分布和粒径分布的模型,并讨论了缺陷通过版图产生电路错误的过程,给出了IC功能成品率模拟器XD-YES的实现。用XD-YES对微电子测试图和实际IC的功能成品率模拟和分析表明,其结果与实际符合很好,从而表明XD-YES的可行性和实用性。 相似文献
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Participating media with an inhomogeneous index of refraction make light follow curved paths. Simulating this in a global
illumination environment has usually been neglected due to the complexity of the calculations involved, sacrificing accurate
physical simulations for efficient visual results.
This paper aims to simulate non-linear media in a more reasonable time than previous works without losing physical correctness.
Accuracy is achieved by solving the Eikonal equation of geometrical optics, which describes the path followed by a light beam
that traverses a non-linear medium. This equation is used in the context of a photon mapping extension. 相似文献