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71.
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   
72.
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   
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74.
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   
75.
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   
76.
Biodeterioration of paint films leads to loss of durability and increased repainting costs. The influence of pigments on the biodeterioration of architectural paint films in the city of Florianópolis, Brazil, was evaluated using ten differently colored acrylic paint films exposed to the environment for 34 months. Fouling (biofilm formation) on the surfaces was assessed macroscopically, using British Standard BS 3900/1989 G6, and microscopically. After 20 months, major colonizers were bacteria and fungi, with some cyanobacteria and few algae; north-facing suede and peach and south-facing ice colors showed 100% cover at this time. The least affected color at all times was blue, with a maximum of 30% cover on south-facing panels after 34 months. North-facing panels were generally more fouled than South-facing. Blue, red, and ceramic colors always performed best. Resistance to fouling may have been due to copper in blue and acidity from sulfur oxides in ceramic pigments. Pigments may prolong paint film life and reduce the need for biocides.  相似文献   
77.
78.
When the component proportions in mixture experiments are restricted by lower and upper bounds, the design space can become an irregular region that can induce multicollinearity among the component proportions. Thus, we suggest the use of ridge regression as a means of stabilizing the estimates of the coefficients in the fitted model. We use fraction of design space plots and violin plots to illustrate and evaluate the effect of ridge regression estimators with respect to the prediction variance and to guide the decision about the value of ridge constant k. We illustrate the methods with three examples from the literature. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
79.
Electrochemical formation of tunable nanoscale oxide layers on biomedical metallic surfaces has recently drawn much attention in biomaterials research. In this study, we report on the cellular response to a unique vertically aligned, laterally spaced nanotube nanostructure made of zirconium oxide (ZrO2) fabricated by anodization. The growth, morphology, and functionality of osteoblasts cultured on ZrO2 nanotubes have been investigated. The initial adhesion and spreading was considerably improved on the nanotube surface as compared to a flat zirconium (Zr) surface without a nanostructure. The morphology of the adhered cells on the nanotube surface elicited a highly organized cytoskeleton with crisscross patterned actin, which was lacking on the flat Zr. Increased alkaline phosphatase activity levels and the formation of calcified extracellular matrix implied improved osteoblast functionality and mineralization on the nanotube substrate. This in vitro study suggests that the ZrO2 nanotubes provided an enhanced osteoblast response and demonstrated their apparent role in providing a platform for bone growth.  相似文献   
80.
Tools were developed for estimating costs of vegetative roofs, rainwater catchment systems, and bioretention facilities. These tools provide a detailed framework to facilitate cost estimation for capital costs, operation and maintenance costs, and life-cycle net present value. The tools can provide users with planning-level cost estimates and serve as a format for cost-reporting for past, current, and future projects. Very little cost data was available in the public forum, and prolific inconsistencies of supporting details were found in the available cost data. To address this, design assumptions were established for each facility type and professionally prepared cost estimates based on these design assumptions were used. Electives in design, such as plant selection and media depth, also greatly affected costs. To make the user aware of these effects, the model separates each option into line items that can be elected or excluded as appropriate. To facilitate collecting future cost data, best management practice (BMP) designers and builders should use these tools to record actual costs and report them to a clearinghouse such as the BMP Database.  相似文献   
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