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141.
Pierre-Henri Horrein Christine Hennebert Frédéric Pétrot 《Journal of Signal Processing Systems》2012,69(1):55-65
This article studies the integration of Graphics Processing Units in a Software Defined Radio environment. Two main solutions are considered, based on two levels of granularity for the parallelization. First, a fine grain parallelism solution, which is an extension of the existing solutions but adapted to operations of large computational complexity, is proposed. Second, an original solution based on coarse grain approach allowing better usage of the computing resources and easier parallelism extraction is described. For both solutions, scheduling and communication design as well as implementation are given, along with integration in the environment. Both solutions have been implemented and compared on different operations types and on multi-operations sequences. It is clearly shown that using the second solution can provide performance improvement, while the first one is not adapted to SDR applications. 相似文献
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144.
Diana Brumini Camilla Bø Furlund Irene Comi Tove Gulbrandsen Devold Donata Marletta Gerd E. Vegarud Christine Monceyron Jonassen 《International Dairy Journal》2013,28(2):109-111
Antiviral activity of Ragusano donkeys' milk proteins was investigated for the effect on echovirus type 5, known to infect the gastrointestinal tract of humans. Three protein fractions were tested; casein (CN), whey protein (WP) and a low molecular whey protein fraction (LWP; <30,000 Da). The antiviral activity of WP and LWP was tested on echovirus type 5 at three concentrations (1, 5 and 10 mg mL?1); CN was assessed only at the lower concentration. All donkey milk protein fractions showed significant inhibition on virus replication at the concentration of 1 mg mL?1, and both WP and LWP fractions showed significant inhibition on the virus replication at all concentrations tested. The strongest antiviral effect was observed for the WP fraction. These findings show that the different whey proteins in donkey milk, probably acting in synergy, exert antiviral activity on echovirus 5 and might contribute to prevent gastrointestinal virus infections in humans. 相似文献
145.
Rainer Dudek Ralf Doering Christine Bombach Bernd Michel 《Microelectronics Reliability》2009,49(8):839-845
Secondary effects on thermal fatigue of solder joints, which frequently have been neglected, were studied by means of the finite element method (FEM). Based on a semi-empirical approach to predict fatigue life by evaluating the cyclic accumulated equivalent creep strain or energy density, effects of organic boards intrinsic properties on solder joint fatigue were investigated. Aspects of more realistic FR-4 board modelling were studied, in particular concerning its in-plane anisotropy and intrinsic warpage behaviour. Intrinsic board warpage was measured on test board level as well as for boards from series production. High intrinsic warpage was in particular found for several test boards. The effects for the worst case scenario observed so far were analysed for both first level and second level interconnects. The change in predicted fatigue life varied between 30% and 500%, the latter most critical effects were found at large QFN components. Another secondary effect studied was to include the frequently neglected interfacial intermetallics into FEM. It turned out that for components with relatively large standoff like LFBGAs the effects were actually negligible, but for the highly miniaturized components like chip resistors CR0201 they are the decisive factor. 相似文献
146.
Researchers investigated the impact of podcasting on student motivation in the online environment during fall 2008 and spring 2009. Data were collected from students enrolled in fourteen online courses at a research university in the United States. One hundred and ninety-one students completed a modified version of the Instructional Materials Motivation Survey (Keller, 2006); it has four subscales: attention, relevance, confidence, and satisfaction. Strong positive relationships between all subscales were detected. Results indicate students were moderately motivated by the use of podcasts in their online courses. Statistically significant differences in student motivation based on gender, class standing, and prior online learning experience were found. Benefits of using podcasts and recommendations for improvement of the multimedia files were offered by users. 相似文献
147.
Dae‐Heung Jang Christine M. Anderson‐Cook 《Quality and Reliability Engineering International》2018,34(3):417-426
Supersaturated designs can potentially be a beneficial tool for efficiently exploring a large number of factors with a moderately sized design. However, because more factors are being considered than there are runs, the stability of the identified factors depends heavily on effect sparsity and the lack of highly influential observations. A helpful tool for the analysis of supersaturated designs is least absolute shrinkage and selection operation (LASSO), which is useful when the effects of many explanatory variables are sparse in a high‐dimensional dataset. To understand the impact of individual observations on the selected factors, the LASSO influence plot was created. This paper describes an application of this plot and its variants that can be used to identify influential points, increase understanding of the impact of individual observations on model parameters, and the robustness of results in analyses with supersaturated designs. These graphical methods can serve as a complement to other regression diagnostics techniques in the LASSO regression setting. 相似文献
148.
Lee Christine M.; Geisner Irene M.; Patrick Megan E.; Neighbors Clayton 《Canadian Metallurgical Quarterly》2010,24(2):342
Social norms for alcohol use are important influences on individual college student drinking. The present study extends social norms research by examining alcohol-related consequences and, in particular, whether similar misperceptions exist regarding the frequency and evaluation of these consequences over time. College student drinkers (N = 624) participating in a longitudinal study completed Web-based surveys assessing alcohol use and related consequences, as well as their beliefs about frequency and evaluation of consequences for the typical college student. Findings suggest that students overestimated how often typical college students experience negative consequences and underestimated how negatively other students evaluated those consequences. Finally, results support a bidirectional model for alcohol-related consequences, possibly indicating a reciprocal, mutually influential feed-forward loop of norms and consequences that promotes maintenance of college student drinking and consequences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
149.
Soybean Allergens Affecting North American Patients Identified by 2D Gels and Mass Spectrometry 总被引:1,自引:0,他引:1
Christine Gagnon Vaino Poysa Elroy R. Cober Stephen Gleddie 《Food Analytical Methods》2010,3(4):363-374
In this study, we compared the immunoglobulin E immunological reactions of 23 soy-allergic, nine soy-sensitive, and four non-allergic
human sera to soybean proteins separated by 1D and 2D gel electrophoresis and screened by Western blot. This method led to
novel allergen identification in soybean proteins by tandem mass spectrometry analysis of reactive proteins. Soybean is one
of the eight most significant foods which provoke allergic reactions among North Americans. Previous studies have identified
several putative allergens present in soybean seeds; however, many of these reports did not employ mass spectrometry to conclusively
identify the allergenic proteins. Reviews have suggested that soybean seeds may contain between 10 and 20 different proteins
responsible for provoking allergic reactions among sensitive patients. We report, in this study of North American patients,
a total of 19 potentially allergenic proteins including ten identified by mass spectrometry and five novel allergens. We have
also made extensive use of soybean lines lacking various subunits of the major seed storage proteins, glycinin and β-conglycinin.
By using these knockout lines in Western blots with patient serum, it was conclusively demonstrated that some patients react
predominantly to only a few proteins, while most react to four to six proteins. The findings herein describe the main allergic
proteins present in soybean seeds, the relative significance of these allergens among North Americans, and some genetic lines
of soybean lacking individual allergens. 相似文献
150.
We analyze the determinants of the real price of crude oil by means of an equilibrium correction model over the last two decades where we focus on the aspects of the physical market that impact on the clearing price. We find that two cointegrating relations affect the changes in prices: one refers to OPEC's behavior, attempting to control prices using its market power and quotas; the other to the coverage rate of OECD expected future demand using inventory behaviors. We derive a forecasting equation for the change in oil prices which we use to assess the speculative elements of the price increases of the period 2000–05. We show that worries alien to the physical markets were the causes of the increase in oil prices and we quantify their overall impact. 相似文献