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排序方式: 共有824条查询结果,搜索用时 15 毫秒
761.
762.
Ciarán Ó Conaire Noel E. O’Connor Alan Smeaton 《Machine Vision and Applications》2008,19(5-6):483-494
In this paper, we propose a framework that can efficiently combine features for robust tracking based on fusing the outputs of multiple spatiogram trackers. This is achieved without the exponential increase in storage and processing that other multimodal tracking approaches suffer from. The framework allows the features to be split arbitrarily between the trackers, as well as providing the flexibility to add, remove or dynamically weight features. We derive a mean-shift type algorithm for the framework that allows efficient object tracking with very low computational overhead. We especially target the fusion of thermal infrared and visible spectrum features as the most useful features for automated surveillance applications. Results are shown on multimodal video sequences clearly illustrating the benefits of combining multiple features using our framework. 相似文献
763.
A new continuous processing method is presented for the production of continuous-fiber-reinforced metal matrix composite (MMC) wires. The process currently yields MMC wires with the diameter of 0.5–1.6 mm at a maximum speed of 0.3 m/s for (fiber)–(metal) combinations of (Al2O3, Si–Ti Carbide, SiC, Carbon)–(Aluminum, 2024A1, 6061A1) with a fiber volume fraction of 0.50–0.65. The process operation, mechanical/materials characteristics of the MMC wires as well as their relationships are described as an overview of the new materials processing technology. 相似文献
764.
Towards a mechatronic compiler 总被引:1,自引:0,他引:1
765.
We introduce a new estimator for the conditional distribution functions under the proportional hazards model of random censorship.
Such estimator generalizes the one proposed by Abdushkurov, Chen and Lin when covariates are present. Asymptotic theory is
given for this estimator. First, we established the strong consistency, and also obtain the rate of this convergence. Then,
an asymptotic representation for the conditional distribution function estimator leads us to derive its asymptotic normality.
The practical performance of the estimation procedure is illustrated on a real data set. Finally, as a further application
of the new estimator, some functionals of interest in survival exploratory analysis are brieflys discussed.
For the second author, this research was supported by a Human Capital postdoc fellowship, under the Programme ERB-CHRX-CT
940693. 相似文献
766.
By removing the cladding on the outside of a bent single-mode optical fiber and exposing a surface at a radius smaller than that of the radiation caustic, the leaky nature of the propagating mode is almost suppressed, and bend loss is effectively eliminated. The practical realization of this effect is described, and a loop with a bend radius of 0.50 mm on standard telecommunications fiber is demonstrated with negligible loss. 相似文献
767.
Nemeth E Fajdiga S Malago J Koninkx J Tooten P van Dijk J 《International journal of food microbiology》2006,112(3):266-274
Oral administration of lactobacilli as probiotics is gaining importance in the treatment of intestinal inflammations. We investigated the effect of non-starter lactobacilli Lactobacillus casei subsp casei 2756, Lactobacillus curvatus 2775, and Lactobacillus plantarum 2142 as well as their spent culture supernatants (SCS) on Salmonella enteritidis 857 growth, interleukin (IL)-8 and heat shock protein 70 (Hsp70) synthesis in undifferentiated crypt-like and differentiated villus-like Caco-2 cells. The cells were infected with graded numbers of non-starter lactobacilli or S. enteritidis 857 for 1 h and allowed to recover for 24 h or exposed to 200 bacteria/cell for 1 h and allowed to recover for different periods of time. In another experiment S. enteritidis 857 was first pre-treated with SCS-lactobacilli for 1 h before infecting the cells. The levels of IL-8 and Hsp70 were assessed using sandwich ELISA and immunostaining of Western blots, respectively. The effect of SCS-lactobacilli on S. enteritidis 857 growth was evaluated by agar plate diffusion test. The non-starter lactobacilli induced a significant increase in the levels of both IL-8 and Hsp70. However, compared with the S. enteritidis 857 induced IL-8 synthesis, the levels of IL-8 induced by the lactobacilli at any equivalent bacterial number were far lower. After exposure of Caco-2 cells to S. enteritidis 857 pre-treated with SCS-lactobacilli, it appeared that their SCS inhibited the S. enteritidis 857 growth and IL-8 synthesis and in addition induced the expression of Hsp70. The differences in response of crypt- and villus-like Caco-2 cells are merely a reflection of their differentiation status. Our data suggest that the beneficial effect of non-starter lactobacilli to the intestinal inflammations might be associated with a decrease of the IL-8 levels. This effect could be mediated, at least in part, by the bacteria themselves or via a secreted antimicrobial product(s) either directly against the pathogens or indirectly through the synthesis of Hsp70. 相似文献
768.
Optimization of Arabinoxylan Isolation from Rye Bran by Adapting Extraction Solvent and Use of Enzymes
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Denisse Bender Renata Nemeth Michaela Wimmer Sylvia Götschhofer Matilde Biolchi Kitti Török Sandor Tömösközi Stefano D'Amico Regine Schoenlechner 《Journal of food science》2017,82(11):2562-2568
Physicochemical and functional properties of arabinoxylans (AXs) can be significantly influenced by their isolation method. Finding balanced process conditions that allow optimal extraction yields while preserving AXs functionality is a challenge. The aim of this study was to determine the effect of different chemical solvents with neutral and alkaline pH on the intrinsic properties and extraction yield of AXs isolated from rye bran. Additionally, the application of xylanases and other cell wall degrading enzymes (Pentopan Mono BG, Deltazym XL‐VR, Viscoflow BG) to solubilize bound AXs was investigated. Results show that the use of Ca(OH)2 for isolation was superior to water and Na2CO3, as it selectively solubilized AXs and delivered isolates with a purity of up to 43.92% AX and a moderate ferulic acid (FA) content (209.35 ± 16.79 mg FA/100 g AX). Application of xylanases was further able to duplicate these achieved AX yields (7.50 to 9.85g AX/100 g bran). Additionally, isolates displayed highest ferulic acid contents (445.18 to 616.71 mg FA/100 g AX) and lowest impurities in comparison to chemical extracted AXs. Rheological characterization of the isolates showed a pronounced shear thinning behavior which fitted well to the power‐law model (R2 > 0.989). Differences in pseudoplasticity of the isolates suggested that structural and chemical properties might have been responsible for this behavior. 相似文献
769.
This article urges counseling psychology researchers to recognize and report how missing data are handled, because consumers of research cannot accurately interpret findings without knowing the amount and pattern of missing data or the strategies that were used to handle those data. Patterns of missing data are reviewed, and some of the common strategies for dealing with them are described. The authors provide an illustration in which data were simulated and evaluate 3 methods of handling missing data: mean substitution, multiple imputation, and full information maximum likelihood. Results suggest that mean substitution is a poor method for handling missing data, whereas both multiple imputation and full information maximum likelihood are recommended alternatives to this approach. The authors suggest that researchers fully consider and report the amount and pattern of missing data and the strategy for handling those data in counseling psychology research and that editors advise researchers of this expectation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
770.
Noel A McCarthy Orla Power Heni B Wijayanti Philip M Kelly Like Mao Mark A Fenelon 《International Journal of Dairy Technology》2017,70(3):415-423
The aim of this study was to determine the effects of calcium chelating agents on the dissolution and functionality of 10% (w/w) milk protein concentrate (MPC) powder. MPC powder dissolution rate and solubility significantly (P > 0.05) increased with addition of sodium phosphate, trisodium citrate (TSC) and sodium hexametaphosphate (SHMP), compared to MPC dispersions alone. Trisodium citrate and SHMP addition increased viscosity as a result of micelle swelling. However, dispersions containing SHMP showed a decrease in viscosity after prolonged time due to micelle dissociation. Overall, MPC powder dissolution was aided by the addition of calcium chelating agents. 相似文献