Theoretical ecology predicts that heterogeneous habitats allow more species to co-exist in a given area. In the deep sea, biodiversity is positively linked with ecosystem functioning, suggesting that deep-seabed heterogeneity could influence ecosystem functions and the relationships between biodiversity and ecosystem functioning (BEF). To shed light on the BEF relationships in a heterogeneous d...

Nature conservation and fisheries management often focus on particular seabed features that are considered vulnerable or important to commercial species. As a result, individual seabed types are protected in isolation, without any understanding of what effect the mixture of seabed types within the landscape has on ecosystem functions. Here we undertook predictive seabed modelling within a coast...

The occurrence of the severe slugging phenomenon in multiphase pipelines can cause serious and troublesome operational problems within the receiving process facilities. This paper describes: the pipeline operability studies on the Dunbar to Alwyn multiphase pipeline regarding riser-induced severe slugging; the control scheme selected to prevent this phenomenon; and the subsequent operating expe...

To investigate the wave- and current-induced seabed response near a fully buried subsea pipeline, two-dimensional coupled model for fluid-seabed-pipeline interaction (FSPI-2D) is developed within framework of COMSOL multiphysics. Different from previous studies, both wave-current nonlinear pipeline-soil contacts are considered in present model. In this paper, Biot’s consolidation mode used to g...

Most multibeams today provide a measure of the received seabed backscatter intensity. With proper radiometric and geometric reduction, the seabed backscatter strength and its angular variation may be derived, which can then be used to attempt seabed classification. Most multibeams, however, are monochromatic in the sense that they transmit using a single center frequency (even if with some puls...

Propagation and reverberation of acoustic fields in shallow waters depend strongly on the spatial variability of seabed geoacoustic parameters, and lack of knowledge of seabed variability is often a limiting factor in acoustic modeling applications. However, direct sampling (e.g., coring) of vertical and lateral variability is expensive and laborious, and matched-field and other long-range inve...

UWB pulse radars that offer target shape estimation are promising as imaging techniques for household or rescue robots. We have already proposed an efficient algorithm for a shape estimation method SEABED which is a fast algorithm based on a reversible transform. SEABED extracts quasi wavefronts from received signals with the filter that matches the transmitted waveform. However, the scattered ...

The analytical solutions of wave induced horizontal and vertical forces on perforated caissons resting on porous elastic seabed have been established. The solution in the seabed is divided into a symmetric part and an anti-symmetric part. A numerical experiment has been carried out to examine the effects on horizontal forces, vertical forces and phase lags between them due to the relative wave ...

RISER, M., GERAUD, J., RASCOL, X., RISER, A. & SAINTMARC, M. (1957) Syndrome de Guillain-Barr6 et Strohl a evolution ascendante avec hypertension intra-cranienne. Bulletin et MWmoires de la Soci&t medicale des Hopitaux de Paris, 73, 689. SARACCO, J.B., GENEVET, J. & MOULY, A. (1971) Atrophie optique et dissociation albumino-cytologique. Bulletin des socigtts d'ophtalmologie de France, 71, 637. ...

Radial profiles of particle velocities were investigated in a 6.1m high methanol-to-olefins cold model experimental device using a TSI laser Doppler velocimeter. The effect of axial height on flow development was not obvious in fully developed region under the same operating condition. Superficial gas velocity and solid circulating rate had significant influence on particle velocity in the cent...