This paper aims at initiating a fundamental understanding of the suspended load transport of river sediment in unsteady flow. Laboratory erosion tests as well as artificial flood experiments are used to evaluate the influence of the transient regime on the transport efficiency of the flow. The erosion experiments reveal that the transport capacity is augmented when the unsteadiness of the flow increases. However, the influence of the transient regime is counteracted by the cohesive properties of the river bed. Field experiments with artificial floods released from a reservoir into a small canal confirm these findings and show a relationship between the friction velocity and the suspended load transport. An appropriate parameter [3 is proposed to evaluate the impact of the transient regime on the transport of suspended sediment.Key words sediment transport; unsteady flow; artificial floods; suspended load; kinematic flow; friction velocity Simulation du transport de sédiment pendant des événements de crue: expériences au laboratoire et sur le terrain Résumé Cette publication se donne pour but d'arriver à une plus grande compréhen-sion fondamentale du transport des matières en suspension pendant un écoulement non-permanent. Des expériences au laboratoire et sur le terrain avec des écoulements artificiels sont réalisées pour évaluer comment un débit non-permanent peut influencer le transport de matière. Les expériences au laboratoire montrent que la capacité de transport est augmentée significativement par le régime non-permanent. Néanmoins, les propriétés cohésives du lit du cours d'eau contrebalancent cette influence. Des expériences sur le terrain, consistant en des crues artificielles issues d'un réservoir dans un petit canal, confirment ces résultats et montrent une relation entre la vitesse de cisaillement et le transport en suspension. Un paramètre (3 est introduit pour évaluer l'influence du régime non-permanent sur le transport de matières en suspension.

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Today, people have only limited, valuable leisure time at their hands which they want to fill in as good as possible according to their own interests, whereas broadcasters want to produce and distribute news items as fast and targeted as possible. These (developing) news stories can be characterised as dynamic, chained, and distributed events in addition to which it is important to aggregate, link, enrich, recommend, and distribute these news event items as targeted as possible to the individual, interested user. In this paper, we show how personalised recommendation and distribution of news events, described using an RDF/OWL representation of the NewsML-G2 standard, can be enabled by automatically categorising and enriching news events metadata via smart indexing and linked open datasets available on the web of data. The recommendations -based on a global, aggregated profile, which also takes into account the (dis)likings of peer friends -are finally fed to the user via a personalised RSS feed. As such, the ultimate goal is to provide an open, user-friendly recommendation platform that harnesses the end-user with a tool to access useful news event information that goes beyond basic information retrieval. At the same time, we provide the (inter)national community with standardised mechanisms to describe/distribute news event and profile information.

News production is characterized by complex and dynamic workflows in which it is important to produce and distribute news items as fast as possible. In this paper, we show how personalized distribution and consumption of news items can be enabled by automatically enriching news metadata with open linked datasets available on the Web of data, thus providing a more pleasant experience to fastidious consumers where news content is presented within a broader historical context. Further we present a faceted browser that provides a convenient way for exploring news items based on an ontology of NewsML-G2 and rich semantic metadata.