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101.
Romain Chesnaux Mélanie LambertJulien Walter Ugo FillastreMurray Hay Alain RouleauRéal Daigneault Annie MoisanDenis Germaneau 《Computers & Geosciences》2011,37(11):1870-1882
Understanding and managing groundwater resources require the integration of a large amount of high-quality data from a variety of sources. Due to the limitations in accessing information related to groundwater and subsurface conditions, the gathering of available existing information is of crucial importance when conducting a successful hydrogeological study. Here, we present an approach for the development of an exhaustive and comprehensive groundwater database through (1) the gathering of relevant sources of information relating to groundwater, and (2) the application of a quality control process in order to screen the data for accuracy and quality. This hydrogeological database is then implemented within a GIS (geographic information system) framework coupled to a Relational Database Management System (RDBMS) as a personal geodatabase (ESRI format) GIS technology. Once established, the spatial database allows a user to request the relevant data required for a specific hydrogeological study. In addition, stratigraphic data stored within the spatial database may be utilized for constructing 3D subsurface hydrostructural models. In order to achieve this objective, the software Arc Hydro Groundwater combined with the ArcGIS spatial database is shown to be appropriate for the 3D structural representation of aquifers (groundwater reservoirs). The innovative contribution of this approach in building 3D hydrostructural subsurface models from a spatial database resides in simplifying the required step-by-step processes by considering a unified compatible combination of “RDBMS-ArcGIS-Arc Hydro Groundwater” technologies. The proposed methodology is illustrated using data from an ongoing project aimed at developing an inventory of the groundwater resources of the Saguenay-Lac-Saint-Jean region, Quebec (Canada). 相似文献
102.
Annie Tordilla Darilay Joshua D. Naranjo 《Computational statistics & data analysis》2011,55(7):2400-2409
In a two-sample location-scale model with censored data, the logrank test is asymptotically efficient when the error distribution is extreme minimum value. On the other hand, the Wilcoxon test is asymptotically efficient when the error distribution is logistic. We propose a pretest for choosing between logrank and Wilcoxon by determining if the error distribution is closer to extreme minimum value or logistic. This adaptive test is compared with the logrank and Wilcoxon tests through simulation. 相似文献
103.
The influence of distillation parameters on the extraction of flavour compounds from the gin botanical Juniperus communis L. using vapour infusion was investigated. The optimum mix of conditions to extract the highest levels of certain compounds was established using a 33-factorial design. Quantification using solid-phase microextraction and gas chromatography coupled mass spectrometry, was performed measuring nine common flavour compounds. The greatest influence was the botanical ratio, whilst the least influential parameter was ethanol concentration for all compounds except terpinen-4-ol. Density functional theory calculations of quantitative structure–activity relationship properties for the flavour compounds were also undertaken to test for molecular influence on solvent extraction. The quantitative structure–activity relationship model showed the highest dipole moment for terpinen-4-ol and the lowest for γ-terpinene. © 2020 The Institute of Brewing & Distilling 相似文献
104.
Gravey Annie Amar Djamel Gravey Philippe Morvan Michel 《Photonic Network Communications》2019,37(3):278-295
Photonic Network Communications - The present paper addresses future network architectures considered for Fixed Mobile Convergence, where users can access resources transparently either through... 相似文献
105.
Minh Tri Nguyen Mariana Tozlovanu Thi Luyen Tran Annie Pfohl-Leszkowicz 《Food chemistry》2007,105(1):42-47
The possible coexistence of three mycotoxins in rice, including aflatoxin B1 (AFB1), citrinin (CIT) and ochratoxin A (OTA), was investigated. The samples of rice were collected in large markets in five provinces of the central region of Vietnam. These toxins were extracted, purified and finally quantified by HPLC with fluorimetry detection. Contamination of AFB1 was found to be the most, followed by OTA, while contamination of CIT was insignificant. The coexistence of CIT with AFB1/OTA in rice was found in high percentage. Some samples overpassed the authorized limit by Europe in OTA and/or AFB1. 相似文献
106.
A key property for predicting the effectiveness of stochastic search techniques, including evolutionary algorithms, is the
existence of a positive correlation between the form and the quality of candidate solutions. In this paper we show that when
the ordering of genomic symbols in a genetic algorithm is completely independent of the fitness function and therefore free
to evolve along with the candidate solutions it encodes, the resulting genomes self-organize into self-similar structures
that favor this key stochastic search property. 相似文献
107.
108.
Fiber units are conserved design motifs that bestow intrinsic stiffness to biological tissues. Collagen fibrils are the fundamental unit of fibrous tissues with controlled assembly and multiscale structure‐function properties. Characteristic non‐linear tissue response is afforded through energy dissipation at the stiff‐soft interfaces of fibril collagen and extrafibrillar matrix components. The goal of this research is to develop a 3D silk hydrogel microfiber platform with bioinspired toughening mechanisms. Batch fabrication and post‐processing renders fibers that can be handled and with tunable features, as well as loading of components to improve material responses. Matrix loading of a glycoprotein, bovine serum albumin (BSA), adds a primary defense mechanism to material failure in the form of sacrificial bonds. This enables nano‐ to micro‐scale rearrangement with strain and improved fiber toughness compared to silk‐only fibers. Further biomimicry is added via matrix loading of a biosilica precursor peptide, R5, enabling biomineralization in the form of silicification. Inorganic mineral deposition of Silk‐BSA‐R5 hydrogel microfibers provides a fibrous scaffold for applications that require fibril‐mineral interfaces for load transduction. This microfiber platform introduces a methodology for meticulous fibrous scaffold design with biomimetic fibril hierarchy, toughening mechanisms, and loading capabilities for systematic tissue engineering applications. 相似文献
109.
110.
Emilie Calvié Lucile Joly-Pottuz Claude Esnouf Philippe Clément Vincent Garnier Jérôme Chevalier Yves Jorand Annie Malchère Thierry Epicier Karine Masenelli-Varlot 《Journal of the European Ceramic Society》2012,32(10):2067-2071
The behavior of alumina nano-particles taken from a commercial powder is investigated during in situ compression experiments in a transmission electron microscope (TEM). Small particles of 40 nm in diameter can undergo severe plastic deformation without failure, whereas brittle fracture is observed for 120 nm sized nano-particles. This is evidence of a critical size under which alumina, at least in the form of nano-particles, cannot be considered as brittle materials even at room temperature and a direct observation of the grinding limit generally observed during ball milling. 相似文献