Autonomous resource-aware scheduling of large-scale media workflows

The media processing and distribution industry generally requires considerable resources to be able to execute the various tasks and workflows that constitute their business processes. The latter processes are often tied to critical constraints such as strict deadlines. A key issue herein is how to efficiently use the available computational, storage and network resources to be able to cope with the high work load. Optimizing resource usage is not only vital to scalability, but also to the level of QoS (e.g. responsiveness or prioritization) that can be provided. We designed an autonomous platform for scheduling and workflow-to-resource assignment, taking into account the different requirements and constraints. This paper presents the workflow scheduling algorithms, which consider the state and characteristics of the resources (computational, network and storage). The performance of these algorithms is presented in detail in the context of a European media processing and distribution use-case

Deep genetic divergence and recent radiations in sand goby <i>Pomatoschistus minutus</i> along European coasts

Understanding evolutionary patterns is more complex in marine compared to continental species because marine species have high effective population sizes and high levels of dispersal due to an apparent lack of barriers. Moreover, phylogeographical breaks in the marine realm such as the Atlantic-Mediterranean transition remain controversial. Therefore a new high-quality phylogeographic analysis was realized for a marine demersal fish, the sand goby Pomatoschistus minutus (Gobiidae, Teleostei). Sand gobies of 12 locations along the full European distribution range were analyzed by sequencing a large fragment of the mitochondrial cytochrome b gene.The phylogenetic results show that P. minutus comprises two deep genealogical lineages, the Mediterranean Sea Clade (MS-Clade) and the Atlantic Ocean Clade (AOClade), that date back to the Early Pleistocene (1.6-0.8 MYA). Even though the sand goby occurs only in a few northern locations in the Mediterranean, the MS-Clade contains the Significant Units (ESU), one off the Western Iberian Peninsula and the other in the marine systems of the North Atlantic (Bay of Biscay, North Sea, Irish Sea and Baltic Sea). This is consistent with two separate palaeorefugia during the Pleistocene glaciations: the Iberian Peninsula and the Bay of Biscay. Less haplotypes were shared among the marine systems of the North Atlantic, indicating a low present-day gene flow. The network analysis showed a recent radiation in each marine system, even in the northern Baltic Sea where the recolonization of P. minutus occurred only 8000 years ago. This phylogeographic pattern will be compared with putatively adaptive loci in order to study the characteristics of local adaptation in the marine environment

Exploring glacial and present evolutionary patterns of a marine goby, <i>Pomatoschistus minutus</i>

A classical understanding of marine fishes is that they have high effective population sizes and high levels of dispersal due to an apparent lack of barriers in the marine environment. The realization of a genetic population structure is therefore thought to be a slow process. To gain insights in this process, it is a challenge to disentangle the interaction between selection, gene flow, population history and genetic drift. The sand goby (Pomatoschistus minutus), which is an important ecological but noncommercial species, was chosen to distinguish between natural and anthropologically induced processes. A spatio-temporal analysis with samples from different localities throughout the species distribution and with two types of genetic markers was performed to assess the neutral genetic population structure. Phylogeographical patterns were studied by sequence cytochrome b (mtDNA). Nine new nuclear microsatellites were developed and used to describe the current genetic diversity and population structure. The genetic structure of the sand goby is best explained by a combination of present and historic factors. Due to its high potential for dispersion and high effective population size, it shows the typical features of a marine fish with a high level of diversity and a limited degree of genetic differentiation. The large genetic distance between the Venetian and all other samples shows that the sand gobies from the Adriatic Sea should be considered as a distinct cryptic species of the genus Pomatoschistus. Low but significant differentiation is observed between Atlantic and western Mediterranean P. minutus. In the Atlantic and Baltic basins, there is evidence for a postglacial range expansion and a weak pattern of isolation-by-distance. Furthermore the results support the hypothesis of a glacial refugium and a fine-scale genetic structure in the southern North Sea. The neutral genetic pattern will be compared with putatively adaptive loci in order to study the genomic characteristics of local adaptation in the marine environment. This should provide a better understanding of how fish respond to changes in the environment

Risk analysis of marine activities in the Belgian part of the North Sea (RAMA): final report

RAMA is a 2-year project (04/2004 - 04/2006) executed by two Belgian partners, Ecolas NV (Environmental Consultancy Agency) and the Maritime Institute (University of Ghent), and financed by the SPSD II research program, specific actions, of the Belgian Science Policy (BELPSO). RAMA aims to assess the environmental risks of spills by commercial shipping activities on the Belgian Part of the North Sea. Shipping patterns, transports of dangerous goods, probability of risks and the potential impact of spill incidents (oil & hazardous and noxious substances) will be assessed. The risk analysis within this project studies both the chances of a spill accident happening and the environmental impacts in case of an accident. The valorisation of the RAMA project will result in a thorough analysis of the current status of the shipping at the North Sea in relation to the issue of safety. The scope of the project will however go beyond the mere result of a fundamental risk analysis of the commercial shipping at the North Sea. It is also aiming at the formulation of recommendations to improve the safety level for the environment and at an optimization of response in the framework of the Belgian "North Sea Disaster Plan"