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101.
Jaouadi Randa Andrieux Guillaume Baudais Jean-Yves Diouris Jean-François 《Wireless Personal Communications》2018,103(2):1101-1112
Binary offset carrier modulation is applied in several signals of the global navigation satellite system (GNSS). It enhanced the robustness of GNSS against the impact of multipath and make the compatibility of GNSS better. However, it has the main drawback of potentially giving biased measurements in acquisition and tracking. The technique we proposed is based on linear fitting with multi-correlator to accomplish unambiguous tracking. The coefficient of each correlator was deduced in this paper. The theoretical analysis and simulation results indicate that the proposed method can performs well on multipath and thermal noise. 相似文献
102.
Jean Blaise Jean Vergès Jean-Fran?ois Wyart Rolf Engleman Jr 《Journal of research of the National Institute of Standards and Technology》1992,97(1):213-216
All known energy levels of neutral platinum (Pt I) are presented, including 119 new levels based on analysis of recent comprehensive observations of the spectrum. These results are taken from a detailed analysis of the spectrum to be published in Journal de Physique II. 相似文献
103.
Jean-François Colonna 《The Visual computer》1995,11(8):447-452
For many scientists, human intelligence and, in particular, its creative potential seem to consist of processes that cannot
be automated by means of a computer. As already shown with fractal geometry, this short note tries to show that the iteration
and combination of very elementary operations can give very complex behaviors and shapes. It gives some practical examples
to encourage reader involvement and new experiments, particularly in classroom settings. 相似文献
104.
From 3D magnetic resonance images to structural representations of the cortex topography using topology preserving deformations 总被引:7,自引:0,他引:7
Jean-François Mangin Vincent Frouin Isabelle Bloch Jean Régis Jaime López-Krahe 《Journal of Mathematical Imaging and Vision》1995,5(4):297-318
We propose an algorithm allowing the construction of a structural representation of the cortical topography from a T1-weighted 3D MR image. This representation is an attributed relational graph (ARG) inferred from the 3D skeleton of the object made up of the union of gray matter and cerebro-spinal fluid enclosed in the brain hull. In order to increase the robustness of the skeletonization, topological and regularization constraints are included in the segmentation process using an original method: the homotopically deformable regions. This method is halfway between deformable contour and Markovian segmentation approaches. The 3D skeleton is segmented in simple surfaces (SSs) constituting the ARG nodes (mainly cortical folds). The ARG relations are of two types: first, theSS pairs connected in the skeleton; second, theSS pairs delimiting a gyrus. The described algorithm has been developed in the frame of a project aiming at the automatic detection and recognition of the main cortical sulci. Indeed, the ARG is a synthetic representation of all the information required by the sulcus identification. This project will contribute to the development of new methodologies for human brain functional mapping and neurosurgery operation planning. 相似文献
105.
Component-based systems permit standardisation and re-usability of code through the use of components. The architecture of component-based systems can be modified thanks to dynamic reconfigurations, which contribute to systems’ (self-)adaptation by adding or removing components without incurring any system downtime. In this context, the present article describes a formal model for dynamic reconfigurations of component-based systems. It provides a way of expressing runtime reconfigurations of a system and proving their correctness according to a static invariant for consistency constraints and/or a user-provided post-condition. Guarded reconfigurations allow us to build reconfigurations based on primitive reconfiguration operations using sequences of reconfigurations and the alternative and the repetitive constructs, while preserving configuration consistency. A practical contribution consists of the implementation of a component-based model using the GROOVE graph transformation tool. This implementation is illustrated on a cloud-based multi-tier application hosting environment managed as a component-based system. In addition, after enriching the model with interpreted configurations and reconfigurations in a consistency compatible manner, component systems’ implementations are related to their specifications by a simulation relation. 相似文献
106.
Jean Pascal Eloundou Emmanuel Girard-Reydet Jean-François Gérard Jean-Pierre Pascault 《Polymer Bulletin》2005,53(5-6):367-375
Summary Above a concentration c* close to 0.3 wt%, blends of 12-hydroxystearic acid (HSA) with diglycidyl ether of bisphenol A (DGEBA) prepolymer mixed at 80°C give thermally reversible physical gels (organogels) on cooling.According with the literature, the turbidity of the gels indicates fibres of rectangular cross-sectional shapes. The slope of the linear melting heats versus concentration is equal to the melting heat of the pure HSA (-182 ± 4 J.g-1).The blends are gels as the elastic modulus G is about ten times larger than the loss one G and G is practically independent of the frequency at a given concentration.The sharp variation of the temperature of the endothermic peak Tpeak, of the time to reach the rubbery plateau tr, of the exponent (G) and of the limiting strain l of the linear viscoelastic domain below 2.5 wt%, is attributed to smaller crystallites in the blend.At a given frequency, G follows a scaling law with the concentration (
), the scaling exponent 1 being equal to 3.87 ± 0.02 at 1 rad.s-1. This indicates that the gel structure is independent of the concentration. 相似文献
107.
Xuehao Lin Jean-François H. Lambert José J. Fripiat Marc Monthioux Agnès Oberlin 《Catalysis Letters》1989,3(2):169-177
The kinetics of gas phase hydrogen uptake into platinized VMoO5.5 to form the bronze H–3.2VMoO5.5 is limited by diffusion of atomic hydrogen from Pt crystallites to the mixed oxide (spillover). It is therefore strongly dependent on the precursor platinum salt (H2PtCl6, Pt(NH3)4Cl2 or Pt(NH3)4(OH)2) as well as on the pretreatment conditions between salt deposition and hydrogen exposure, since these parameters determine platinum dispersion. While traditional techniques for metal dispersion measurement, such as CO adsorption or H2 adsorption/titration are inappropriate for this system, semi-quantitative information on Pt dispersion can be extracted from a simple analysis of the kinetics. These dispersion estimates are in reasonably good agreement with average particle sizes obtained from TEM micrographs. 相似文献
108.
Benjamin Negrevergne Alexandre Termier Marie-Christine Rousset Jean-François Méhaut 《Data mining and knowledge discovery》2014,28(3):593-633
In this paper, we present Para Miner which is a generic and parallel algorithm for closed pattern mining. Para Miner is built on the principles of pattern enumeration in strongly accessible set systems. Its efficiency is due to a novel dataset reduction technique (that we call EL-reduction), combined with novel technique for performing dataset reduction in a parallel execution on a multi-core architecture. We illustrate Para Miner’s genericity by using this algorithm to solve three different pattern mining problems: the frequent itemset mining problem, the mining frequent connected relational graphs problem and the mining gradual itemsets problem. In this paper, we prove the soundness and the completeness of Para Miner. Furthermore, our experiments show that despite being a generic algorithm, Para Miner can compete with specialized state of the art algorithms designed for the pattern mining problems mentioned above. Besides, for the particular problem of gradual itemset mining, Para Miner outperforms the state of the art algorithm by two orders of magnitude. 相似文献
109.
110.
Jean-François Gravel Matthias Geissler Sébastien Chapdelaine Karel Boissinot Benoît Voisin Isabelle Charlebois Hugo-Pierre Poirier-Richard Alexandre Grégoire Maurice Boissinot Michel G. Bergeron Teodor Veres Denis Boudreau 《Microfluidics and nanofluidics》2014,16(6):1075-1087
This paper describes the design, functioning and use of a portable detection platform for multiplex nucleic acid testing. The system features a bead-supported DNA hybridization assay performed inside a microfluidic cartridge. Polystyrene particles modified with DNA capture probes are confined in the detection area and exposed to a solution of fluorescently labeled target DNA strands. The cartridge, fabricated from inexpensive thermoplastic polymers, allows for conducting up to eight assays in parallel. The detection instrument is equipped with a pneumatic module and a manifold lid serving as an interface to mediate fluid displacement on the cartridge. The fluorescence signal deriving from each assay is recorded by a semi-confocal fluorescence reader embedded in the detection platform. The compact design of the instrument and its level of integration make it possible to obtain an analytical result in less than 15 min, while only few manual steps need to be performed in between. A proof-of-concept demonstration involving Cy3-labeled, PCR-amplified genomic DNA confirms the ability to detect Bacillus anthracis in a multiplexed single-assay format using lef and capC genes. Limits of quantification are on the order of 1 × 109 copies/μL for lef targets. 相似文献