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51.
Mathieu Thevenot Sylvie Dousset Philippe Schmitt-Kopplin 《The Science of the total environment》2009,407(14):4297-4302
Diuron is frequently detected in some drinking water reservoirs under the Burgundy vineyards, where organic amendments are applied. The environmental effect of these amendments on pesticide transport is ambiguous: on the one hand it could enhance their retention by increasing soil organic carbon content; on the other hand, dissolved organic matter (DOM) could facilitate their transport. Elutions were performed using columns packed with glass beads in order to investigate DOM-diuron interactions, and the possible co-transport of diuron and DOM. Four organic amendments (A, B, C and D) were tested; C and D were sampled at fresh (F) and mature (M) stages. An increase in diuron leaching was observed only for A and DF amendments (up to 16% compared to the DOM-free blank samples), suggesting a DOM effect on diuron transport. These results could be explained by the higher DOM leaching for A and DF compared to B, CF, CM and DM increasing diuron-DOM interactions. These interactions seem to be related to the aromatic and aliphatic content of the DOM, determining formation of hydrogen and non-covalent bonds. The degree of organic matter maturity does not seem to have any effect with amendment C, while a reduction in diuron leaching is observed between DF and DM. After equilibrium dialysis measurement of diuron-DOM complexes, it appeared that less than 3% of the diuron applied corresponded to complexes with a molecular weight > 1000 Da. Complexes < 1000 Da could also take part in this facilitated transport. 相似文献
52.
In this paper, we propose a controllable embedding method for high‐ and low‐dimensional geometry processing through sparse matrix eigenanalysis. Our approach is equally suitable to perform non‐linear dimensionality reduction on big data, or to offer non‐linear shape editing of 3D meshes and pointsets. At the core of our approach is the construction of a multi‐Laplacian quadratic form that is assembled from local operators whose kernels only contain locally‐affine functions. Minimizing this quadratic form provides an embedding that best preserves all relative coordinates of points within their local neighborhoods. We demonstrate the improvements that our approach brings over existing nonlinear dimensionality reduction methods on a number of datasets, and formulate the first eigen‐based as‐rigid‐as‐possible shape deformation technique by applying our affine‐kernel embedding approach to 3D data augmented with user‐imposed constraints on select vertices. 相似文献
53.
Gisèle Boiteux Pascal Dublineau Michel Feve Christophe Mathieu Gérard Seytre Jacek Ulanski 《Polymer Bulletin》1993,30(4):441-447
Summary The curing of different epoxy-amine model systems which present only gelification and/or vitrification processes has been followed with the evolution of their viscoelastic and electrical behaviours during the network formation. Some attempts are performed to correlate the significant evolution of the mechanical and electrical parameters with the physico-chemical changes of these well defined chemical systems during their hardening and complete curing. 相似文献
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Slobodan Ilić Mathieu Salzmann Pascal Fua 《International Journal of Computer Vision》2007,72(2):159-178
Using silhouettes in uncontrolled environments typically requires handling occlusions as well as changing or cluttered backgrounds,
which limits the applicability of most silhouette based methods. For the purpose of 3-D shape modeling, we show that representing
generic 3-D surfaces as implicit surfaces lets us effectively address these issues.
This desirable behavior is completely independent from the way the surface deformations are parame-trized. To show this, we
demonstrate our technique in three very different cases: Modeling the deformations of a piece of paper represented by an ordinary
triangulated mesh; reconstruction and tracking a person’s shoulders whose deformations are expressed in terms of Dirichlet
Free Form Deformations; reconstructing the shape of a human face parametrized in terms of a Principal Component Analysis model.
Electronic supplementary material Electronic supplementary material is available for this article at and accessible for authorised users.
This work was supported in part by the Swiss National Science Foundation 相似文献
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A rule induction approach for determining the number of kanbans in A just-in-time production system 总被引:2,自引:0,他引:2
Ina S. Markham Richard G. Mathieu Barry A. Wray 《Computers & Industrial Engineering》1998,34(4):717-727
A procedure based on rule induction is presented which can be used to determine the number of kanbans while simultaneously determining the critical factors in a just-in-time (JIT) production system. In particular, the classification and regression tree (CART) technique developed by Brieman et al. [Breiman, L., Friedman, J., Olshen, R. and Stone, C. J., Classification and Regression Trees. Wadsworth, Belmont, CA, 1984.] is used to automatically generate rules from dynamic shop floor data. An example application of the methodology is presented and the advantages of a rule induction approach are explained. The paper concludes with a discussion of future research directions. 相似文献
60.
Aspergillus carbonarius is an ochratoxin producing fungus that has been considered to be responsible of the ochratoxin A (OTA) contamination in grapes and wine. In order to monitor and quantify A. carbonarius, a specific primer pair Ac12RL_OTAF/Ac12RL_OTAR has been designed from the acyltransferase (AT) domain of the polyketide synthase sequence Ac12RL3 to amplify 141 bp PCR product. Among the mycotoxigenic fungi tested, only A. carbonarius gave a positive result. This specific primer pair was also successfully employed in real-time PCR conjugated with SYBR Green I dye for the direct quantification of this fungus in grape samples. A positive correlation (R(2)=0.81) was found between A. carbonarius DNA content and OTA concentration in 72 grape samples, allowing for the estimation of the potential risk from OTA contamination. Consequently, this work offers a quick alternative to conventional methods of OTA quantification and mycological detection and quantification of A. carbonarius in grapes. 相似文献