Search results for "Algorithm"

Sex-specific effects of natural and sexual selection on the evolution of life span and ageing in Drosophila simulans

2014

Summary Variation in the strength of age-dependent natural selection shapes differences in ageing rates across species and populations. Likewise, sexual selection can promote divergent patterns of senescence across the sexes. However, the effects of these processes on the evolution of ageing have largely been considered independently, and interactions between them are poorly understood. We use experimental evolution to investigate how natural and sexual selection affect life span and ageing in Drosophila simulans. Replicate populations were evolved under lifetime monogamy (relaxed sexual selection) or lifetime polyandry (elevated sexual selection) and at one of two temperatures, 25 °C (rela…

Chronic Mesenteric Ischemia: Critical review and guidelines for management

2011

Background CMI is caused by chronic occlusive disease of mesenteric arteries. In such an uncommon disease, clear recommendations are strongly needed. Unfortunately, treatment options for symptomatic CMI are still controversial and no guidelines exist. Methods A systematic literature review of the last 25-years was conducted through MEDLINE, Embase, and Cochrane Review/Trials register to identify studies reporting on CMI treatment with more than 10 patients. Primary outcomes were perioperative mortality and morbidity rates. Secondary outcomes were survival rates, primary and secondary patency rates, vessels treated, CMI recurrence, follow-up (FU), technical success (TS), and in-hospital leng…

Analytical model for the long- distance tracer-transport in plants

2011

International audience; Recent investigations of long-distance transport in plants using non-invasive tracer techniques such as C radiolabeling monitored by positron emission tomography (PET) combined with magnetic resonance imaging (MRI) revealed the need of dedicated methods to allow a quantitative data analysis and comparison of such experiments. A mechanistic compartmental tracer transport model is presented, defined by a linear system of partial differential equations (PDEs). This model simplifies the complexity of axial transport and lateral exchanges in the transport pathways of plants (e.g. the phloem) by simulating transport and reversible exchange within three compartments using j…

Parallel global optimization : structuring populations in differential evolution

2010

On automatic algorithm configuration of vehicle routing problem solvers

2019

Many of the algorithms for solving vehicle routing problems expose parameters that strongly influence the quality of obtained solutions and the performance of the algorithm. Finding good values for these parameters is a tedious task that requires experimentation and experience. Therefore, methods that automate the process of algorithm configuration have received growing attention. In this paper, we present a comprehensive study to critically evaluate and compare the capabilities and suitability of seven state-of-the-art methods in configuring vehicle routing metaheuristics. The configuration target is the solution quality of eight metaheuristics solving two vehicle routing problem variants.…

ON-LINE CONSTRUCTION OF A SMALL AUTOMATON FOR A FINITE SET OF WORDS

2012

In this paper we describe a "light" algorithm for the on-line construction of a small automaton recognising a finite set of words. The algorithm runs in linear time. We carried out good experimental results on real dictionaries, on biological sequences and on the sets of suffixes (resp. factors) of a set of words that shows how our automaton is near to the minimal one. For the suffixes of a text, we propose a modified construction that leads to an even smaller automaton. We moreover construct linear algorithms for the insertion and deletion of a word in a finite set, directly from the constructed automaton.

Modélisation de la mobilité : la génération de trafic à l'échelle régionale

2006

Public transport management is currently going through important changes, passing from one scale to another: decentralizing from the national level and extending at the local level. The range of transport management powers of the French administrative regions have widened, thus creating new management problems. Within the context of these new questions, our research proposes management solutions which take into account both the continual evolution of daily mobility and the new scales of transport management. More specifically, we considered a specific stage often neglected in geographical approaches to the suject. This stage called traffic generation consists in modelling the process of cho…

An EEMD Aided Comparison of Time Histories and Its Application in Vehicle Safety

2017

In the context of signal processing, the comparison of time histories is required for different purposes, especially for the model validation of vehicle safety. Most of the existing metrics focus on the mathematical value only. Therefore, they suffer the measuring errors, disturbance, and uncertainties and can hardly achieve a stable result with a clear physical interpretation. This paper proposes a novel scheme of time histories comparison to be used in vehicle safety analysis. More specifically, each signal for comparison is decomposed into a trend signal and several intrinsic mode functions (IMFs) by ensemble empirical mode decomposition. The trend signals reflect the general variation a…

Recursion at the crossroads of sequence modeling, random trees, stochastic algorithms and martingales

2013

This monograph synthesizes several studies spanning from dynamical systems in the statistical analysis of sequences, to analysis of algorithms in random trees and discrete stochastic processes. These works find applications in various fields ranging from biological sequences to linear regression models, branching processes, through functional statistics and estimates of risk indicators for insurances. All the established results use, in one way or another, the recursive property of the structure under study, by highlighting invariants such as martingales, which are at the heart of this monograph, as tools as well as objects of study.

Mise en œuvre d’une architecture de gestion de collision pour le déploiement efficace d’un NoC sur multi-FPGA

2015

International audience; Le déploiement d’un NoC (Network On Chip) sur plusieurs FPGA nécessite que des routeurs partagent un même lien de communication entre FPGAs, créant des goulots d’étranglement [1]. Dans ce papier, nous proposons une structure de gestion de collision intégrée entre le NoC et le point d’accès du protocole FPGA. Cette structure est basée sur les algorithmes utilisés dans les réseaux informatiques et adaptée aux NoC [2].