Lakes in Gypsum Karst: Some Examples in Alpine and Mediterranean Countries

Numerous lakes of varying types have been studied in these areas. Their origin proceeds from the geomorphological processes in the gypsum karst: land subsidence or collapses in relation with the active dissolution of the gypsum and other evaporites, particularly in depth, at the groundwater level. Most are small lakes, often ephemeral ponds in the alpine gypsum karsts, or flooded sinkholes in alluvial plains, in keeping with the fluctuations of the water-table. However, in the Mediterranean lands and Central Europa, some lacustrine basins are more important expanse; they arise from a complex evolution, and put various environmental problems. So are particularly studied the case of the lake of Besse in Provence, and in comparison the problems of the lakes of Pergusa (Sicily) and Banyoles (Catalonia)

A Little Contribution to the Karst Terminology: Special or Aberrant Cases of Poljes?

Običajna definicija kraškega polja je »velika zaprta kraška depresija z ravnim dnom, kraškim odtokom in strmimi pobočji«. Toda na dinarskem krasu je cela vrsta različnih kraških polj. V prispevku so navedeni glavni kriteriji za razvrščanje polj ter posebej poudarjeno vprašanje različne stopnje v razvoju kraškega polja. Vsebina je zbrana in povzeta v preglednici, ki obenem ponuja nove rešitve pri razvrščanju kraških polj ter podaja primerjavo med dinarskim krasom ter krasom v drugih sredozemskih in alpskih deželah.A usual definition of polje states that it is “great closed karst basin with flat bottom, karstic drainage and steep peripheral slopes”. But the Dinaric karst shows a wide range of poljes. The article discusses the main criteria of polje definition and the different degrees of evolution of the polje are emphasised. The essentials are gathered in the table with new tentatives on classification of poljes and comparing the Dinaric karst with other Mediterranean and Alpine countries. 

A Genetic Algorithm to Schedule Workflow Collections on a SOA-Grid with Communication Costs

International audienceIn this paper we study the problem of scheduling a collection of workflows, identical or not, on a SOA grid. A workflow (job) is represented by a directed acyclic graph (DAG) with typed tasks. All of the grid hosts are able to process a set of task types with unrelated processing costs and are able to transmit files through communication links for which the communication times are not negligible. The goal is to minimize the maximum completion time (makespan) of the workflows. To solve this problem we propose a genetic approach. The contributions of this paper are both the design of a Genetic Algorithm taking the communication costs into account and the performance analysis

SNPs by AFLP (SBA): a rapid SNP isolation strategy for non‐model organisms

Despite the great potential of single nucleotide polymorphism (SNP) markers in evolutionary studies, in particular for inferring population genetic parameters, SNP analysis has almost exclusively been limited to humans and ‘genomic model' organisms, due to the lack of available sequence data in non‐model organisms. Here, we describe a rapid and cost effective method to isolate candidate SNPs in non‐model organisms. This SNP isolation strategy consists basically in the direct sequencing of amplified fragment length polymorphism bands. In a first application of this method, 10 unique DNA fragments that contained 24 SNPs were discovered in 11.11 kb of sequenced genomic DNA of a non‐model species, the brown trout (Salmo trutta

Task scheduling to extend platform useful life using prognostics.

International audienceIn this paper, we aim at maximizing the useful life of a heterogeneous distributed platform which has to deliver a given production. The machines (one nominal mode and several degraded ones). Depending on the profile, a machine reaches a given throughput. At each time the sum of the machine throughputs that are currentky running determines the global throughput. Moreover, each machine is supposed to be monitored and a prognostic module gives its remaining useful life depending on both its past and future usage (profile). the objective is to configure the platform so as to reach the demand as long as possible. We propose to discretize the time into periods and to choose a configuration for each period. We propose an Integer Linear Programming (ILP) model to find such configurations for a fixed time horizon. Due to the number of variables and constraints in the ILP, the largest horizon can be computed for small instances of the problem. For larger ones , we propose polynomial time heuristics to maximize the useful life. Exhaustive simulations show that the heuristics solutions are close to the optimal (5% in average) in the case where the optimal horizon can to computed. for other platforms with a very large number of machines, simulations assess the efficienty of our heuristics. The distance to the theoretical maximal value is about 8% in average

Utilisation du {D}istributed {S}panning {T}ree en tant qu'{O}verlay

International audienceLe Distributed Spanning Tree est une topologie originale developpee pour ameliorer les performances des mecanismes de recherche par flooding en terme de vitesse de recherche et en terme de charge supportee. Ces mecanismes de recherche diffusent des messages par l intermediaire d un graphe de communication. Deux types de topologie sont communement utilises pour construire ces overlay networks : ce sont les graphes et les arbres. En utilisant une vision originale des arbres, il est possible de faire disparaitre leurs goulets d etranglements. Nous decrivons cette structure ainsi que deux algorithmes de parcours qui lui sont associes. Puis, les gains de performances du Distributed Spanning Tree par rapport aux graphes et aux arbres classiques sont soulignes a l aide de simulations

Comparison of Batch Scheduling for Identical Multi-Tasks Jobs on Heterogeneous Platforms

International audienceIn this paper we consider the scheduling of a batch of the same job on a heterogeneous execution platform. A job is represented by a directed acyclic graph without forks (intree) but with typed tasks. The execution resources are distributed and each resource can carry out a set of task types. The objective function is to minimize the makespan of the batch execution. Three algorithms are studied in this context: an on-line algorithm, a genetic algorithm and a steady-state algorithm. The contribution of this paper is on the experimental analysis of these algorithms and on their adaptation to the context. We show that their performances depend on the size of the batch and on the characteristics of the execution platform

Adaptation d'un algorithme optimal d'ordonnancement en régime permanent pour des lots bornés

International audienceLe contexte de cet article est l ordonnancement de lots bornes de travaux identiques sur une plate-forme d execution heterogene comme la grille. Les travaux executes sont des graphes de t?ches orientes et sans cycle (DAG), en forme d anti-arbre. Les t?ches sont de plusieurs types et les n{oe}uds de la plate-forme ne sont pas toujours en mesure d executer tous les types de t?ches. Le probleme de minimisation du temps d execution d un lot est un probleme NP-Complet. Sous l angle du regime permanent, il est possible de decrire le probleme sous la forme d un programme lineaire donnant une solution optimale pour l ordonnancement cyclique de lots infinis. Lorsque les lots sont bornes, les resultats restent bons bien que sous optimaux. Nous montrons ici que les phases d initialisation et de terminaison ajoutent un sur-co?t qui penalise le temps global d execution. Nous montrons ensuite le lien entre la taille de ces phases et la taille de la periode de l ordonnancement cyclique et donnons un algorithme permettant le calcul de la periode minimale. Des experimentations, obtenues par simulations avec SimGrid, illustrent en fin d article le gain apporte par le choix d une periode minimal