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排序方式: 共有4317条查询结果,搜索用时 31 毫秒
31.
With worldwide energy consumption rising, there is a need to reduce energy use of the housing stock. While this general idea is well-known, there is an overwhelming amount of product data and manufacturers claims through which the homebuilder or designer must sort to make informed selections of energy-efficient upgrades. The main objective of this research was to identify cost effective–energy efficient upgrades from a group of 16 commonly available choices, and rank them according to the most beneficial for the least cost. This study was conducted in Phoenix, Arizona, and included a sample of 30 production-style homes typical of the Phoenix metropolitan area. Energy-simulation software was used to perform energy evaluations and derive the benefits of each upgrade. The cost of each upgrade was obtained from a database of national average costs and from a local context. Differences in the selection of beneficial upgrades vary dramatically with the source of the cost information. This research provides a generic methodology that can be used by builders and designers to select appropriate energy-efficient upgrades for a given geographic area that will provide high operating benefits relative to the amount of capital investment. 相似文献
32.
Assessed the retention of memory units for word-like strings of letters using the perceptions of 120 undergraduates in 2 experiments in determining how frequently various letters appeared. A series of strings was presented at 1 of 3 exposure durations. Within the series, the frequencies of occurrence of different strings and of the letters composing the strings were varied orthogonally. Results indicate that, at relatively long exposure durations, Ss could discriminate the frequency of occurrence for both strings and their constituent letters. The formation of global-level (string) memory units was indicated by judgments of string frequency being unaffected by either the frequencies of their component letters or experimental conditions (brief exposures) that prohibited accurate judgment of letter frequency. Although judgments of letter frequency were sometimes biased by the frequency of the strings containing the letters, the success with which the judgments discriminated different levels of letter frequency did not depend on the activation of string-level memory units. Furthermore, Ss' frequency judgments for letters were not predictable from their recall of the strings containing the letters. Results provide evidence for the formation of element-level (letter) memory units. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
Howard Kenneth I.; Krause Merton S.; Vessey John T. 《Canadian Metallurgical Quarterly》1994,31(2):302
The immediate goal of any clinical trial is to determine to which of a specified set of treatments future patients are to be assigned, particularly when analyzing data from clinical trials. When the outcome distributions of Experimental (E) and Control (C) treatments overlap, differences between treatment group means are not conclusive and may not be very informative, so a display of the overlapped frequency distributions and a summary measure of the probability of a random patient in E doing better than a random patient in C are needed. When outcome distributions overlap, the question of statistical model becomes crucial even when there are very significant differences between group means and very large effect sizes. Determining what patient variables interact with treatments is the route to optimal assignment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
Bo Jiang Jeffrey L. Brown Jane Sheraton Nathalie Fortin Howard Bussey 《Yeast (Chichester, England)》1994,10(3):341-353
We have identified three yeast genes, KES1, HES1 and OSH1, whose products show homology to the human oxysterol binding protein (OSBP). Mutations in these genes resulted in pleiotropic sterol-related phenotypes. These include tryptophan-transport defects and nystatin resistance, shown by double and triple mutants. In addition, mutant combinations showed small but apparently cumulative reductions in membrane ergosterol levels. The three yeast genes are also functionally related as overexpression of HES1 or KES1 alleviated the tryptophan-transport defect in kes1Δ or osh1Δ mutants, respectively. Our study implicates this new yeast gene family in ergosterol synthesis and provides comparative evidence of a role for human OSBP in cholesterol synthesis. 相似文献
35.
Levin Harvey S.; Mendelsohn Dianne; Lilly Matthew A.; Fletcher Jack M.; Culhane Kathleen A.; Chapman Sandra B.; Harward Harriet; Kusnerik Lori; Bruce Derek; Eisenberg Howard M. 《Canadian Metallurgical Quarterly》1994,8(2):171
To investigate the relationship of severity of pediatric closed head injury (CHI), the contribution of frontal lobe lesions, and age at testing (6–10 yr olds vs 11–15 yr olds) to cognitive deficit, 134 head-injured patients were given the Tower of London (TOL) task and underwent magnetic resonance imaging. 89 normal controls were given the TOL for comparison. Severity of CHI and age at testing were strongly related to cognitive performance on the TOL, including the frequency of breaking the rules. Volume of frontal lobe lesion (but not extrafrontal lesion) contributed to the prediction of perfomance on the TOL even after severity of injury was taken into account. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
Howard R. Moskowitz Michele Reisner Barbara Itty Rachel Katz Bert Krieger 《Food quality and preference》2006,17(7-8):536-551
Innovation is often left to insight and serendipity. A lot of what researchers call innovation is actually a process by which one can make the individual consumer or practitioner more ‘creative’. Although it is important to work with the creative individual in hopes of coming up with the better ‘idea’ and new product/service opportunity, an equally valid albeit novel and counterintuitive approach systematizes creativity in a ‘research-driven machine’. This paper presents an approach to the systematization, based upon the point of view that creativity and innovation comprise the recombination of components into new blends. Given this point of view, to then spur innovation requires a systematic database that the user can access, with tools to help manipulate that database. The paper shows how such a database can be constructed and then used to create a novel product. The approach provides a general framework for the sensory professional to become more involved in the early stages of product development, where the focus is on the conceptual aspects of food features rather than on their physical manifestations in actual products. 相似文献
37.
Kessler Ronald C.; Foster Cindy; Webster Pamela S.; House James S. 《Canadian Metallurgical Quarterly》1992,7(1):119
There is inconsistency in the literature on the relationship between age and depressive symptoms. Although a careful review shows that some of this inconsistency can be reconciled by recognizing the nonlinear relationship (J. P. Newmann, 1989), 2 additional issues remain unclear. One is that most previous studies used depression screening scales that contain somatic items that could introduce an age bias. The other is that most previous studies combined samples of men and women even though there is evidence that the sex difference in depressive symptoms varies with age. These 2 issues are addressed in this article, using analyzed data from 2 large national surveys. There is a consistent, but quite modest, nonlinear association between age, somatic, and nonsomatic depressive symptoms in both surveys. There is no significant sex difference in the age curves. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
39.
This paper analyses inter-organizational networks that link together firms operating in the food processing and distribution industry in the UK. In doing so, the paper draws on insights recently developed by Mark Casson that treat inter-firm networks as an institutional response to the changing costs and opportunities of information management. Detailed analysis of product innovation and supply-chain management issues within the industry, exemplified by the growth of chilled ready-meals, leads to the identification of two distinct but complementary inter-firm networks: a network of control and a network of innovation. In each case, the study finds that the critical information is derived from the retailers' interface with consumers and thus that these information-based networks are effectively controlled by the leading supermarket chains. The study's conclusions are considered in relation to the recent findings of the UK Competition Commission following its investigation into grocery retailing in Britain. 相似文献
40.
Tresadern P.A. Thies S.B. Kenney L.P.J. Howard D. Goulermas J.Y. 《Pervasive Computing, IEEE》2008,7(2):62-69
The clinical set-up tool integrates fast parameter selection and a user-friendly interface to help electrical muscle stimulators more efficiently treat patients with neurological injuries. A key challenge in increasing functional electrical stimulation systems' clinical acceptance is facilitating or automating parameter selection, optimization, and programming to make the underlying engineering transparent to the user. To this end, we present the clinical set-up tool (CST), a finite-state-machine-based controller that integrates accurate, automatic parameter optimization in an intuitive user interface. Unlike other approaches, we employ a numerical algorithm that uses real-life data and well-defined criteria to rapidly optimize parameter values. 相似文献