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71.
Lepage Kathy; Kratochwill Thomas R.; Elliott Stephen N. 《Canadian Metallurgical Quarterly》2004,19(1):1
Assessments of consultants, clients, and consumer satisfaction were used to examine the effects of a competency-based consultation training program conducted over 4 years. Using a multiple-baseline framework to assess training effects on consultants and single-case study designs to evaluate changes in client behavior, a number of significant results were found. As predicted, consultants (N=24) significantly increased their consultation skills and knowledge, but with no change in attitudes toward behavioral intervention techniques. Supervised consultation with preschool teachers and parents resulted in a range of behavior change in clients (N=39), with an overall effect size of 0.51. Consumers reported a high level of satisfaction with training and consultation services. Results of a long-term follow-up with consultants indicated positive views and use of consultation. The discussion focuses on these results, and implications for consultation training and future research directions. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
72.
The three-dimensional structure of the paramyosin filament has been reconstructed from images obtained when the specimen is tilted at different angles about its long axis. The micrographs were correlated spatially using gold marker beads and digitized. The different views contained in each micrograph were combined using a computational technique involving Fouri***er transforms and the resulting three-dimensional images are presented as various sets of serial sections. The results confirm that the Bear-Selby (1956) net can be seen at all levels in the specimen. 相似文献
73.
Joshua Elliott Meredith Franklin Ian Foster Todd Munson Margaret Loudermilk 《Computational Economics》2012,39(3):219-241
While computable general equilibrium (CGE) models are a well-established tool in economic analyses, it is often difficult
to disentangle the effects of policies of interest from that of the assumptions made regarding the underlying calibration
data and model parameters. To characterize the behavior of a CGE model of carbon output with respect to two of these assumptions,
we perform a large-scale Monte Carlo experiment to examine its sensitivity to base year calibration data and elasticity of
substitution parameters in the absence of a policy change. By examining a variety of output variables at different levels
of economic and geographic aggregation, we assess how these forms of uncertainty impact the conclusions that can be drawn
from the model simulations. We find greater sensitivity to uncertainty in the elasticity of substitution parameters than to
uncertainty in the base-year data as the projection period increases. While many model simulations were conducted to generate
large output samples, we find that few are required to capture the mean model response of the variables tested. However, characterizing
standard errors and empirical probability distribution functions is not possible without a large number of simulations. 相似文献
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Phase-change (PC), nonvolatile memory (NVM) materials, such as Ge2Sb2Te5 (GST), encode stored digital binary data as structural changes in the material. Reversible, ultrafast (nanosecond) transformations between metastable semiconducting/nonreflective amorphous and near-metallic/reflective crystalline states occur as a result of Joule heating, caused by applied voltage/laser write pulses, in electronic/optical NVMs, respectively. The canonical PCM, GST, was originally discovered and developed for optical NVM; although it also works as an electronic NVM (phase-change random-access memory, PCRAM) material, nevertheless it is not optimal in this role. In this contribution, I will discuss the effects of “doping” (or chemical modification) of GST, with elements such as nitrogen or first-row transition metals, to improve PC characteristics, such as crystal grain size, and optical-reflectivity contrast for optical NVM, and to introduce additional PC functionality, for example, magnetism for electronic NVM, respectively. These studies have been carried out by ab initio molecular-dynamics (AIMD) simulations, in which new compositions of doped PCMs have been obtained by a process of in silico materials discovery. I will also describe a strategy to decrease the rate-limiting crystallization time of PCMs, which does not also decrease long-term data retention in the amorphous state (i.e., deleterious spontaneous crystallization), by means of the use of “priming” prepulses. AIMD simulations indicate the structural-ordering origin of this priming behavior. In this way, we have reduced the crystallization time of GST, from ~10 ns down to ~500 ps, well below the critical switching time of ~1 ns needed to replace volatile Si-based CMOS DRAM by an NVM-equivalent, so-called “universal memory”. Finally, I will outline very recent work which demonstrates that GST PCM cells can also be used to perform “in-memory” Boolean logic operations, thereby combining memory and processing operations in the same cell. 相似文献
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Jonathan W. Elliott Scott Glick Rodolfo Valdes-Vasquez 《International Journal of Construction Education and Research》2019,15(2):118-135
The use of building information modeling (BIM) is well established in architecture, engineering and construction. However, previous studies note a lack of BIM expertise in academia, leading to slow adoption and limited knowledge on which to base BIM-related content. To improve course development, it is important to understand students’ perceptions of BIM-related subject matter. This study exposed estimating students (n = 214) to a model-based quantity takeoff (QTO) tutorial using Revit. Students’ perceptions of a Revit-based BIM’s usefulness for easily providing reliable and accurate material quantities were measured using a pre-test, tutorial and post-test design. Results revealed significant differences in students’ mean levels of agreement that an accurate QTO is completed for an estimator with the click of a button when a design team generated BIM model is available. Results also revealed significant differences in students’ level of agreement that a Revit-based BIM makes performing QTO by hand obsolete. This study provides educators’ insight into students’ perceptions of BIM use in QTO. Understanding student perceptions is paramount for construction management educators when designing a course and attempting to convey the value of foundational estimating skills while acknowledging the existence of more technologically advance estimating methods. Limitations and opportunities for further research are discussed. 相似文献
79.
Creep recovery of acrylate urethane/acrylate networks was investigated as a function of time and temperature. An important outcome was the capacity for superimposition of experimental data obtained at various temperatures. Arrhenius type temperature dependence of the creep recovery was also observed. The master curve obtained did not significantly depend on the measuring mode of creep recovery or the crosslink density, and the response could be approximated by the Bueche theory. The dynamic mechanical properties of the systems were also investigated. Retardation spectrum L obtained from the dynamic mechanical data overlapped with that obtained from the creep recovery data. The activation energy obtained from the temperature dependence of the shift factor aT also agreed with that obtained from the temperature dependence of the creep recovery. © 1996 John Wiley & Sons, Inc. 相似文献
80.
Epidemics can particularly threaten certain sub-populations. For example, for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the elderly are often preferentially protected. For diseases of plants and animals, certain sub-populations can drive mitigation because they are intrinsically more valuable for ecological, economic, socio-cultural or political reasons. Here, we use optimal control theory to identify strategies to optimally protect a ‘high-value’ sub-population when there is a limited budget and epidemiological uncertainty. We use protection of the Redwood National Park in California in the face of the large ongoing state-wide epidemic of sudden oak death (caused by Phytophthora ramorum) as a case study. We concentrate on whether control should be focused entirely within the National Park itself, or whether treatment of the growing epidemic in the surrounding ‘buffer region’ can instead be more profitable. We find that, depending on rates of infection and the size of the ongoing epidemic, focusing control on the high-value region is often optimal. However, priority should sometimes switch from the buffer region to the high-value region only as the local outbreak grows. We characterize how the timing of any switch depends on epidemiological and logistic parameters, and test robustness to systematic misspecification of these factors due to imperfect prior knowledge. 相似文献