Search results for "Partition"
showing 10 items of 411 documents
Col : A Data Collection Protocol for Vanet
2012
International audience; In this paper, we present a protocol to collect data within a vehicular ad hoc network (VANET). In spite of the intrinsic dynamic of such network, our protocol simultaneously offers three relevant properties: (1) It allows any vehicle to collect data beyond its direct neighborhood (i.e., vehicles within direct communication range) using vehicle-to-vehicle communications only (i.e., the infrastructure is not required); (2) It tolerates possible network partitions; (3) It works on demand and stops when the data collection is achieved. To the best of our knowledge, this is the first collect protocol having these three characteristics. All that is chiefly obtained thanks…
Os desincentivos à aposentadoria antecipada e tardia por parte da seguridade social espanhola
2009
El objetivo principal del trabajo es analizar, desde una óptica financiero-actuarial, la existencia y amplitud de los desincentivos a la jubilación distinta de la ordinaria (65 años) que aplica la Seguridad Social en España. Para el desarrollo del trabajo se ha utilizado una nueva metodología basada en la combinatoria, en lugar de trabajar con datos de carreras laborales reales o de utilizar carreras generadas aleatoriamente. Además, se han aplicado técnicas financieras y actuariales. El presente artículo se ubica dentro de los estudios que analizan la equidad de los sistemas de pensiones, y, en concreto, de pensiones de jubilación del Régimen General en España. Aunque con un carácter meram…
Co‐occurrence patterns in a steppe bird community: insights into the role of dominance and competition
2023
Spatial co-occurrence patterns are determined by environmental factors, such as food availability or habitat characteristics and by biotic associations. When resources are limited, competition which implies a dominant hierarchy can shape species assemblage. Here, we study space and time co-occurrence of steppe passerines during the breeding season in a natural steppe habitat, its modulation by environmental filtering, potential biotic interactions and random processes. We applied the joint species distribution model of hierarchical modelling of species community (HMSC) to data on species presence–absence and environmental, temporal and spatial covariates acquired from seven plots in a natur…
Partition of volatile compounds in pea globulin–maltodextrin aqueous two-phase system
2014
International audience; This study is based on the assumption that the off-flavour of pea proteins might be decreased using the retention of volatile compounds by a mixture with another biopolymer. The partition of volatile compounds in an aqueous system containing pea protein and maltodextrins was followed under thermodynamic incompatibility conditions. Firstly, the phase diagram of the system was established. Then, the partition of aroma compounds between the phase rich in protein and the phase rich in maltodextrin was measured by SPME–GC–MS. There was a transfer of volatile compounds during phase separation. Variations of pH were also used to vary the retention of volatile compounds by p…
Detection of cosmic filaments using the Candy model
2004
We propose to apply a marked point process to automatically delineate filaments of the large-scale structure in redshift catalogues. We illustrate the feasibility of the idea on an example of simulated catalogues, describe the procedure, and characterize the results. We find the distribution of the length of the filaments, and suggest how to use this approach to obtain other statistical characteristics of filamentary networks.
Vapour partition of aroma compounds in strawberry flavoured custard cream and effect of fat content
2008
International audience; Gas–matrix partition coefficients (k) of volatile compounds of a strawberry flavour added to a complex model system (custard dessert, COST action 921 recipe) were determined. The influence of fat content on the volatility of the strawberry aroma compounds was investigated using full fat milk- (FFM) and skimmed milk- (SM) custards. For the purpose of this study, the phase ratio variation (PRV) method was used because of its easy application for a mixture of volatiles without requiring any calibration. From the 15 aroma compounds present in the flavouring mixture, seven were volatile enough to be detected and concentrated enough to allow the calculation of k values. Ga…
Retention/release equilibrium of aroma compounds in fat-free dairy gels
2010
BACKGROUND: The replacement of fat by thickeners in fat-free yoghurts leads to an important modification of aroma compound partitioning, with an impact on aroma perception. Investigation of retention/release equilibria allows a good understanding of aroma compound behaviour depending on food composition. RESULTS: Vapour/liquid equilibria of ten aroma compounds (two esters, two ketones, three aldehydes and three alcohols) in several media were studied to investigate the influence of pectin addition to fat-free dairy gel on the retention/release equilibrium. The partition coefficient of each aroma compound was measured by headspace analysis at equilibrium in six media (pure water, low-methoxy…
How composition and process parameters affect volatile active compounds in biopolymer films
2012
Abstract Active edible films based on chitosan and containing an active aroma compound have been investigated. The influence of the composition of the film forming solution (solvent, plasticizers, nanoparticles, emulsifiers and aroma traps) and process parameters (temperature and viscosity) on drying kinetics, water content, colour, aroma compound retention and partition coefficient was studied. Solvent evaporation rate was increased by addition of ethanol. Water evaporation was delayed by glycerol. The aroma retention during film drying was directly related to the water content. The drying temperature had opposite influences according to the composition of the solvent and additives. Increa…
Characterizing Cavities in Model Inclusion Fullerenes: A Comparative Study
2001
Abstract: The fullerene-82 cavity is selected as a model system in order to test several methods for characterizing inclusion molecules. The methods are based on different technical foundations such as a square and triangular tessellation of the molecular surface, spherical tessellation of the molecular surface, numerical integration of the atomic volumes and surfaces, triangular tessellation of the molecular surface, and cubic lattice approach to the molecular volume. Accurate measures of the molecular volume and surface area have been performed with the pseudorandom Monte Carlo (MCVS) and uniform Monte Carlo (UMCVS) methods. These calculations serve as a reference for the rest of the meth…
Does second phase content control the evolution of olivine CPO type and deformation mechanisms? A case study of paired harzburgite and dunite bands i…
2021
Abstract We have examined the microstructures and crystallographic preferred orientations (CPOs) of six “paired” harzburgite and dunite samples from a small (~ 1 km2) area in the Ellis Stream Complex, Red Hills Massif, Dun Mountain ophiolite belt in New Zealand. Here, banded peridotites with isoclinal folds, E-W striking vertical foliations and vertical lineations are inferred to result from shear on vertical planes that overprint previous mantle structures. The samples contain five different olivine CPOs: typically known as A, C, D, E and AG-types. The co-located harzburgite and dunite of each pair show different CPOs (e.g., A vs E type). In each pair, dunite generally has larger grain siz…