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M. Taroni C. J. W. Breward P. D. Howell J. M. Oliver R. J. S. Young 《Journal of Engineering Mathematics》2012,73(1):93-119
We present a two-dimensional large-aspect-ratio model for the off-contact screen printing of a power-law fluid. We extend
the work of White et al. (J Eng Math 54:49–70, 2005) by explicitly including the fluid/air free surface that is present beneath the screen ahead of the squeegee. In the distinguished
parameter limit of greatest interest to industry, the process is quasi-steady on the time-scale of a print and can be analysed
in three separate regions using the method of matched asymptotic expansions. This allows us to predict where the fluid transfers
through the screen, the point at which it first makes contact with the substrate, and the amount of fluid deposited on the
substrate during a print stroke. Finally, we show that using a shear-thinning fluid will decrease the amount of fluid transferred
ahead of the squeegee, but increase the amount of fluid deposited on the substrate. 相似文献
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Oliver Plettenburg 《Israel journal of chemistry》2019,59(1-2):29-36
In early times, the drug discovery process was mainly based on profiling of new medications in in vivo systems. In the absence of knowledge on enzymatic structures, biochemical signaling or precise cellular processes, researchers were dependent on knowledgeable readout of phenotypic effects in living animals. 相似文献
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Selecting an optimal return policy requires taking into account two effects: the potential positive effect on sales and the potential negative effect of higher costs. We propose a two-step model, in which we first utilize a robust regression to explain purchase behavior, and then apply a zero-inflated negative binominal regression to model the return behavior. We apply this model to data from the most important online platform in China and obtain three main findings. First, the adoption of return policies results in increased sales, while reputation works as a moderator in this process. Second, good reputation and traditional customer friendly return policies (like the Seven-Day Return policy) can significantly increase the number of returns, while more guarantee credibility (enhanced by Guarantee Money) is related to fewer returns. Taken together, both the Seven-Day Return policy (profit increase of +0.29 %) and Guarantee Money (profit increase of +0.016 % per Yuan guarantee) ultimately increase firms’ profit. 相似文献
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Object
Histology is the gold standard for confirming thermally induced necrosis. Generally, however, no specimen is obtained from thermal ablation therapy for pathological examination. The aim of this study was to provide evidence for the relationship between temperatures reached and resulting tissue coagulation during laser ablation in a near-physiological ex vivo lung tumor model by combining viability staining and direct temperature measurement. 相似文献130.
Oliver Schwab Helmut Rechberger Robert Holnsteiner 《?sterreichische Wasser- und Abfallwirtschaft》2016,68(9-10):435-442
The influence of anthropogenic processes on global material flow systems increasingly dominates the influence of natural processes. In this context, the provision of detailed knowledge on material flow systems is relevant for decision makers in resource policy. This information can be provided in the form of one-year material balances or, if repeated over a period of consecutive years, in the form of national resource budgets. In national resource budgets, all relevant flows of a material through a national economy are balanced and displayed in neatly arranged diagrams. By updating these material balances over a series of years, the development of material stocks can be estimated. Upcoming challenges both regarding supply and disposal of materials can be identified. Comprehensive balances are useful for decision makers in resource policy and, moreover, as an information basis for future exploitation of anthropogenic resources. However, both availability of data and possibilities for assessing the reliability of data are very limited. In this work, a methodology for investigating and evaluating the information basis of national resource budgets is presented. The methodology includes procedures for systematic characterization of resource budget data and formal procedures for evaluating their reliability. From a scientific perspective, the methodology contributes to understanding material flow systems better. It also enables implementing procedures towards national resource budgets in an administrative context. 相似文献