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Shasha Zhang Carlo Badiola Mirko Schoenitz Edward L. Dreizin 《Combustion and Flame》2012,159(5):1980-1986
Materials combining high energy density of metals with the biocidal activity of halogens are of interest for applications aiming to inactivate harmful aerosolized microorganisms by combined thermal and chemical effects. This effort develops nanocomposite Al-halogen materials to replace pure Al as a fuel additive in energetic formulations. Cryogenic milling of elemental aluminum and iodine is used to prepare powder-like composite materials for laboratory tests. In such materials, iodine is stabilized in aluminum matrix and is released when the materials are heated and ignited. Al·I2 composite powders with the iodine concentration from 10 to 30 wt.% were prepared. Iodine release by and oxidation of such materials were investigated using thermo-gravimetric analysis. Ignition temperatures of the prepared powders were determined at the heating rates of 1000–22,000 K/s using an electrically heated filament. Composite powders ignite at lower temperatures compared to pure Al powders. Combustion characteristics of the prepared materials were investigated using a constant volume explosion test for aerosolized powders and laser ignition test for individual particles. In both combustion experiments pure Al served as a reference. Higher combustion rate and greater total pressure were observed for the aerosolized clouds of composite powders with 15 and 20 wt.% of iodine. For individual particles, the burn times were slightly longer and flame temperatures were slightly lower compared to those of pure aluminum. Both overall iodine concentration and its stability in the composite powders affected their ignition and combustion characteristics. 相似文献
53.
Bruce G. Cameron Edward F. Crawley Jakub Kwapisz Alicia McNeill 《Engineering Management Journal; EMJ》2017,29(3):128-139
Platforming has become an important means of cost-sharing among industrial products. However, many firms face systemic downward pressure on commonality, with the result that many platforms realize less commonality than intended. Past research has hypothesized that divergence is the result of conflicting tensions between product customization/optimization and cost control. This article investigates the control and incentive levers available to platform managers to shape the behavior of the organization when divergence opportunities arise. Management levers are drawn from a series of 12 industrial case studies, stemming from investigations of the causes of divergences. These management levers are categorized as technical levers, financial levers, and organizational levers. This article illustrates each of the management levers with examples from the case studies. 相似文献
54.
Edward Vine Michael Sullivan Loren Lutzenhiser Carl Blumstein Bill Miller 《Energy Efficiency》2014,7(4):627-640
The use of experiments— particularly randomized controlled trials (RCTs) where subjects are randomly assigned to treatment and control conditions—has rarely been applied to the process of improving the design of energy efficiency programs and, more fundamentally, to determining the net savings from energy efficiency programs. This paper discusses the use of experimentation in the energy efficiency program field with the hope of explaining how these experiments can be used, and identifying the barriers to their use will cause more experimentation to occur. First, a brief overview of experimental methods is presented. This discussion describes the advantages and disadvantages of conducting experiments in the context of the development and evaluation of energy efficiency programs. It then discusses barriers to the use of experimental methods (including cost and equity issues) and suggests some ways of overcoming these barriers. Finally, recommendations are made for implementing key social experiments, discussing the types of energy efficiency programs and issues that can make use of experimentation and variables that one might use for selecting treatments. 相似文献
55.
Edward W.N. Bernroider Christina W.Y. Wong Kee-hung Lai 《International Journal of Project Management》2014
This study explores whether an Enterprise Resource Planning (ERP) implementation project mediates the relationship between dynamic pre-adoption capabilities and ERP-enabled business improvements. The results from our field survey of large ERP adopters in Austria suggest that the effects of the two out of three selected dynamic capabilities are dependent on the properties of the underlying organizational transformation project. While external information acquisition and IT governance capabilities are fully mediated by the performance of the ERP implementation project, decision making only directly impacts business capabilities. These results further our understanding about the role of the implementation project for ERP value creation and the different natures of capability relationships. We call for more research on co-presence conditions related to dynamic capabilities and IT transformation project performance. 相似文献
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J. Edward Jackson 《技术计量学》2013,55(1):197-199
A short-cut rule has been devised for dicotomous data and ill-conditioned quantitative data to test for a one-sided difference between two groups. The rule is defined in terms of a critical count (CC) and a critical difference (CD). For a CC of 4, 8, or 12 the .05 rule is CD equal to 4, 5, or 6, respectively, and the .Ol rule is CD equal to 5, 6, or 7, respectively. 相似文献
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The selection procedures used currently and since 1977 for award of the Frank Wilcoxon and Jack Youden prizes are described. Using real data from the 1976 awards competition, it is shown that different methods of combining judges' ratings would yield different winners, and that which procedure is best is not intuitively obvious. Finally it is shown how the current method was chosen on the basis of probability of correct selection considerations. 相似文献