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11.
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Eric P. Kvam Ph.D. Srikanth B. Samavedam B.Tech. 《JOM Journal of the Minerals, Metals and Materials Society》1994,46(3):47-51
The Ge-Si on Si epilayer system, besides being an interesting technological system in its own right, is a superb model for strained-layer studies. The point defect and symmetry defect structures associated with compound semiconductors can be avoided, allowing a focus on the mechanics of the system. Dislocation sources, glide behavior, and performance effects have been examined for strained-layer systems. Surprises have appeared along the way, but these materials are now becoming characterized well enough for industrial device applications. 相似文献
13.
Eric Keto Roger Ball John Arens Garrett Jernigan Margaret Meixner 《Journal of Infrared, Millimeter and Terahertz Waves》1992,13(11):1709-1725
We present a characterization of some processes affecting the performance of solid state array cameras designed for ground based astronomical imaging in the 8–13μm atmospheric window. Our discussion includes a novel model for electron-hole generationrecombination noise based on the probable pathlength of an electron in a photoconductor. We use the Berkeley mid-IR Array Camera as an example. For this camera, the results show that the total optical system composed of the camera, a 3m telescope, and the atmosphere has an efficiency of about 3%, a 1σ noise equivalent flux density of 25 mJy min?1/2arcsec?2 measured over a Δλ/λ=10% band width, and a noise equivalent expressed as the ambient temperature thermal black body noise of 23%. 相似文献
14.
M. Nyoka G. Akdogan R. H. Eric N. Sutcliffe 《Metallurgical and Materials Transactions B》2003,34(6):833-842
The process of mixing and solid-liquid mass transfer in a one-fifth scale water model of a 100-ton Creusot-Loire Uddeholm
(CLU) converter was investigated. The modified Froude number was used to relate gas flow rates between the model and its protoype.
The influences of gas flow rate between 0.010 and 0.018 m3/s and bath height from 0.50 to 0.70 m on mixing time were examined. The results indicated that mixing time decreased with
increasing gas flow rate and increased with increasing bath height. The mixing time results were evaluated in terms of specific
energy input and the following correlation was proposed for estimating mixing times in the model CLU converter: T
mix=1.08Q
−1.05
W
0.35, where Q (m3/s) is the gas flow rate and W (tons) is the model bath weight. Solid-liquid mass-transfer rates from benzoic acid specimens immersed in the gas-agitated
liquid phase were assessed by a weight loss measurement technique. The calculated mass-transfer coefficients were highest
at the bath surface reaching a value of 6.40 × 10−5 m/s in the sprout region. Mass-transfer coefficients and turbulence parameters decreased with depth, reaching minimum values
at the bottom of the vessel. 相似文献
15.
In this article, the authors seek to strengthen the theoretical foundation of team and cell formation through the inclusion of human factors. They distinguish three types of team characteristics: global, shared, and compositional attributes. In this last category, they also deal with diversity in teams by addressing three types of variables: demographic characteristics, skills and knowledge, and personality traits. In addition, the authors address the relevance of the structure of diversity in cells. For each of the above‐mentioned groups of team characteristics, their potential impact on team functioning is worked out and discussed with simultaneous consideration of the characteristics of the team task. Three industrial examples are included to illustrate the importance of including worker, team, and work characteristics when designing manufacturing cells. © 2006 Wiley Periodicals, Inc. Hum Factors Man 16: 1–15, 2006. 相似文献
16.
The behavioral response (e.g. changes in indoor temperatures, attention to window and door openings) to residential technical efficiency improvements (e.g. attic insulation, storm windows) is an important and largely unresolved issue. Although there is considerable discussion concerning the extent to which households take back some of the energy savings due to technical efficiency improvements in increased comfort, there is almost no empirical evidence on the subject.Detailed electricity billing data (from mid-1981 to mid-1983) were analyzed for 79 households that received financial assistance from the Bonneville Power Administration to retrofit their homes in mid-1982. The mean retrofit expenditure in these homes was $1900; the mean reduction in annual electricity use was 4700 kWh, of which 83% was due to reductions in space heating electricity use. Analysis of the electricity billing data suggests that these households increased their indoor temperature settings after retrofit by almost 1 °F on average. This temperature increase led to an estimated average loss of almost 600 kWh of electricity saving. In other words, roughly 10% of the energy saving due to retrofit was taken back in terms of increased comfort. These results concerning changes in indoor temperatures should be viewed cautiously because of limitations in the analytical method and the large variation across households. 相似文献
17.
Rainwater collection as a possible water source in developing countries is introduced. The major parameters in calculating the size of the tank are defined. Six methods that have been used previously to relate demand, storage, reliability and the rainfall pattern are compared to the Ottawa Model over a wide range of demands. 相似文献
18.
19.
Paul Louis George Eric Seveno 《International journal for numerical methods in engineering》1994,37(21):3605-3619
This paper presents a mesh generation method of the advancing-front type which is designed in such a way that the well-known difficulties of the classical advancing-front method are not present. The retained solution consists of using the first steps of a Voronoï–Delaunay method to construct a background mesh which is then used to govern the algorithm. The two-dimensional case is considered in detail and possible extensions to adaption problems and three dimensions are indicated. 相似文献
20.
Responds to M. F. Hoyt's (see record 1995-22250-001) commentary on T. F. Van Denburg and E. J. Van Denburg's (see record 1994-18427-001) response to Hoyt's (see record 1994-18395-001) commentary on Van Denburg and Van Denburg's (see record 1993-06526-001) article about a case of premature therapy termination. Issues related to limits and flexibility in treatment are addressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献