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51.
52.
Deutsch A. Smith H.H. Rubin B.J. Krauter B.L. Kopcsay G.V. 《Advanced Packaging, IEEE Transactions on》2006,29(1):11-20
A new technique is described for reducing computational complexity and improving accuracy of combined power distribution and interconnect noise prediction for wide, on-chip data-buses. The methodology uses lossy transmission-line power-blocks with frequency-dependent properties needed for the multigigahertz clock frequencies. The interaction between delta-I noise, common-mode noise, and crosstalk and their effect on timing is illustrated with simulations using representative driver and receiver circuits and on-chip interconnections. 相似文献
53.
PURPOSE: The purpose of this study was to record the fluoride released measured in parts per million of four fluoride composite resins for five years. MATERIALS AND METHODS: Four fluoridated composites were separated into four groups. Two composite resins with high viscosity were core materials, Ti-Core with titanium (group 1) and Ti-Core Natural (group 2) and the other two resins studied were low viscosity post cements Flexi-Flow cement with titanium (group 3) and Flexi-Flow Natural (group 4). The fluoride release was studied under four experimental conditions. Three replications were studied in each condition. Fluoride release was measured for 260 weeks (5 years). STATISTICAL METHODS: A one-way analysis of variance (ANOVA) was used to compare the average weekly release followed by a Student-Newman-Keuls (SNK) pairwise multiple comparison test. All results were considered statistically significant if p < 0.05. RESULTS: The ANOVA analysis released a significant statistical interaction between group and week (p < 0.0001). Further analysis showed that the average weekly release for Ti-Core with titanium did not differ from Ti-Core Natural, and that Ti-Core with titanium and Ti-Core Natural differed from both Flexi-Flow Natural and Flexi-Flow with titanium, which were not different from one another. CONCLUSIONS: Ti-Core with titanium (Group 1) and Ti-Core Natural (Group 2) released a greater amount of fluoride than Flexi-Flow with titanium (Group 3) and Flexi-Flow Natural (Group 4). The fluoride released from these fluoridated resin composites are similar to reported ranges of other fluoride releasing dental restoration materials. 相似文献
54.
Micrometeorites-submillimetre-sized particles derived from asteroids and comets-occur in significant quantities in deep sea sediments, and the ice sheets of Greenland and Antarctica. The most abundant micrometeorites are cosmic spherules, which contain nickel-rich spinels that were crystallized and oxidized during atmospheric entry, therefore recording the oxygen content in the uppermost atmosphere. But the use of micrometeorites for detecting past changes in the flux of incoming extraterrestrial matter, and as probes of the evolution of the atmosphere, has been hampered by the fact that most objects with depositional ages higher than 0.5 Myr show severe chemical alteration. Here we report the discovery of unaltered cosmic spherules in a 1.4-Gyr-old sandstone (red bed) from Finland. From this we infer that red beds, a common lithology in the Earth's history, may contain substantial unbiased populations of fossil micrometeorites. The study of such populations would allow systematic research on variations in the micrometeorite flux from the early Proterozoic era to recent times (a time span of about 2.5 Gyr), and could help to better constrain the time when the atmospheric oxygen content was raised to its present level. 相似文献
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The mass spectra of several amine picrates were found to consist of the amine spectrum superimposed on, and hardly disguised by, that of picric acid. The mass spectrum of an amine isolable only as the picrate can thus be obtained. 相似文献
57.
Deutsch Francine M.; Ruble Diane N.; Fleming Alison; Brooks-Gunn J.; Stangor Charles 《Canadian Metallurgical Quarterly》1988,55(3):420
The self-definitional processes accompanying the transition to motherhood were examined in this study. A cross-sectional sample of more than 600 women who were planning to get pregnant within 2 years, pregnant, or in the postpartum stage completed extensive questionnaires pertaining to their experiences of pregnancy and motherhood. On the basis of the assumption of the "self-socialization" perspective that individuals actively construct their identities in response to life transitions, our analyses focused on the role of information-seeking in the developing self-definitions of women becoming mothers. As predicted, (a) women actively sought information in anticipation of a first birth, (b) they used this information to construct identities incorporating motherhood, and (c) after the birth the determinants of their self-definitions shifted from indirect sources of information to direct experiences with child care. Hence, consistent with the self-socialization perspective, information-seeking did play an important role in the women's developing self-conceptions during this life transition. Mechanisms by which information gathered may alter self-conception are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Based on Rogerian self theory and research on sex role stereotypes, the present study examined sex-role concepts of self and others and their relationship to personal adjustment. 128 college women and men used the Bem Sex-Role Inventory to describe their concepts of real self, ideal self, ideal other sex, and belief about the other sex's ideal other. Ss' personal adjustment was measured by the Revised Bell Adjustment Inventory. The following 3 hypotheses were supported for female Ss but not for males: (a) Concepts of self and others were dissimilar and ranked least-to-most sex typed in the order predicted. (b) Perceptions of the other sex's ideal were inaccurate. (c) Sex typing was associated with poor adjustment. Contrary to prediction, sex typing in males was associated with good adjustment. Results are discussed in terms of the Rogerian theory of concept discrepancy and S. Bem's (1974) notion of androgeny. Implications for counseling with female clients are noted. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
E.S. Deutsch 《Pattern recognition》1973,5(2):121-132
The paper discusses the idea of iterating the conversion of a continuous-tone picture from binary to Gray code representation. A simple recursive function is defined by means of which the value of the ith bit representing a picture point's grey level after the mth iteration is determined. The resulting rearrangement of grey levels as well as that of the bits throughout the planes is discussed next. The iteration is shown to repeat after 2″ steps, where n is the number of bit planes representing the picture. A data compression scheme is developed on the basis that prior to exact repetition, approximate repetitions take place during the iterations, and the resulting picture is almost the same as the original. 相似文献
60.
Single-pass gain has been measured for flowing CO2 , CO2 -N2 , CO2 -He, CO2 -N2 -He, and CO2 -N2 -H2 mixes. The gain for CO2 -N2 mixes varies as d-0.9, whered is the tube diameter. The diameter dependence of the gain is less pronounced for CO2 - N2 -He mixes; a peak gain of 4.7 dB/m was obtained in a 1/2 in diam tube. Fluorescence data indicate that the upper laser level population is saturated at 100 mA in all cases. The addition of He, H2 , or O2 depopulates the lower laser level; helium further increases the population of the upper laser level. The addition of CO increases the population of the upper laser level, probably by resonant transfer from the excited vibrational states of CO. 相似文献