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This paper describes the investigation and development of the Gas Metal Arc Welding (GMAW) process for applications at water depths where manned intervention is not feasible. Whilst arc stability is known to deteriorate with increasing water depth it has been shown that overall process stability may be retained at depths up to 2500m (8200ft). Control is dependent on adaptive modification of the power supplied to the welding arc to minimise undesirable arcing phenomena which in turn can lead to destabilisation and/or spatter production. Initial welding trials in a high pressure gaseous environment have shown that sound welds can be produced at these depths with acceptable toughness moderate hardness levels and high strengths.

Hydrocracking technology is a key process for keeping in stride with the market evolution toward increasing distillate share and more severe quality specifications. Previous generation hydrocracking catalysts had limited cracking activity leading to high capital and operating costs. IFPís zeolite-based catalyst and optimized process design enables substantial savings on capital and operating costs. Unlike classical processes the IFP technology gives enough flexibility for economically converting sour crude or coker VGOs which are available at low price. Furthermore hydrocrackers enable the production of high quality lube oil base stocks. The disadvantages of amorphous based hydrocrackers namely the production of excessive amounts of low viscosity products have been largely alleviated with zeolite based hydrocracking. The full panoply of high quality oil grades from transformer oil to the bright stocks are thus recovered. The multi-grade lubricants of the future such as 0 W and 5 W are readily produced.

A new hydrodynamic analysis is performed on a ducted propeller operating with a pre-swirl stator in non-uniform flow. The analysis shows the device has improved the propulsion performance in terms of energy savings. The hydrodynamic interaction between duct propeller and stator is investigated using a boundary element method and lifting surface theory. Special computer programs have been designed to apply the methods to two different devices. The results show an increase in the ducted propeller when the stator is present compared with that of ducting alone. The results are compared to other published methods of analysis.

For subsea pipelines installed in areas with uneven seabed free spans may occur and fatigue failure due to vortex induced vibrations (VIV) is one of the main concerns related to these spans. In order to install pipelines in such areas the safety against fatigue failure from in-line (IL) and cross-flow (CF) VIV must be documented. Although maximum oscillation amplitudes in the IL direction are considerably smaller than the maximum amplitudes in the CF direction the IL fatigue damage normally prevails and may limit the allowable span length. Methods based on force coefficient have until recently been limited to CF VIV due to lack of hydrodynamic coefficients for IL response. This paper presents results from forced IL oscillation experiments of a smooth rigid cylinder in uniform flow. The results are presented as dynamic in-line coefficients for the pure IL regime i.e. reduced velocity between 1 and 4 at Reynolds number 24.000. The results are compared with IL results from free oscillation experiments found in the literature.

An air supported type VLFS is proposed by the authors. This idea has been already proposed. However it wasn't handled a flexible structure. The program code is developed for the analysis of the hydrodynamic forces on the VLFS with the air cushion. The potential flow theory is applied and the pressure distribution method is used for the analysis of the wave pressures. The zero-draft is assumed in this method. The pressure and volume change of the air cushion are linearized. In this paper basic characteristics of the elastic deformations of the air-supported flexible floating structures are investigated. The effectiveness is confirmed and the behaviour of the water waves in air chamber areas is discussed.

Recent advances in marine data sensing technologies and high-speed high-resolution side scan sonars raise a series of data management challenges for the hydrographer. The use of GIS (geographic information system) technology is promoted in order to provide effective and efficient data management for processed hydrographic data. ESRI has recently completed research on an implementation of an object-oriented GIS data model (Geodatabase) and applications (ArcGID). The model lends itself well to database designs and applications associated with the collection documentation distribution and analysis of large amounts of vector raster and surface modelling data (that is a data warehouse). It also provides the end user with the options of setting states and behaviours for each data object. Using this approach provides the means of capturing-modelling ocean data and enabling the existence of 'intelligent data objects' and methods to distribute the data to end-users.

After extensive studies showing extreme marine temperature changes in the Galapagos hydrothermal vents were finally discovered in 1977. More than a decade later the shrimp Rimicaris exoculata found near the vents was discovered to have the photoreceptor rhodopsin capable of detecting low levels of light optimally at 560 nm and at infrared blackbody radiation. Researchers then theorised about the possibility of hydrothermal vents as a light source. There are many theories revolving around the source of non-thermally based visible light emissions from deep-sea hydrothermal vents. Although many of these theories have been proved possible in a controlled laboratory environment none have been directly linked to hydrothermal vents through on-site experimentation and evaluation. A new theory of hydrothermal vent illumination by way of amplified Cerenkov radiation through internal plume reflection is presented. This theory includes the already known creation of visible light by muons in seawater created by the bombardment of the Earth by extraterrestrial neutrinos.

The purpose of the study is to evaluate the feasibility of using the Direct Electrical Heating (DEH) technology on subsea flowlines as part of the Concept Development Phase of the Ichthys Gas Field Development. The study is to confirm the electrical requirements in early indications that the use of DEH will provide the required heating for the subsea pipes/flowlines as required preventing/inhibiting hydrate formation and also wax deposition in the flowlines in the event of a shut down situation in the Central Processing Facility (CPF). The second objective is to confirm the power requirements that will allow warming of the flow lines during or prior to regular cold starting of wells and associated flowlines.

The R&D group at Unisys GSG Canada has investigated and implemented a Multi-Sensor Data Fusion (MSDF) demonstration model that can fuse surveillance information from on-board sensors of the Canadian Patrol Frigate (CPF). The project has shown that performance enhancements can be achieved for the CPF command and control system (CCS) in terms of automating the target identity estimation continuous track correlation and information display. The architecture and capabilities of the MSDF model are outlined and details of a CPF simulator used to provide realistic development conditions are given. Some results and analysis obtained for an air surveillance scenario are given. An improved fusion system that can integrate information from other sensors is now under development.

Model testing for ultra deep water projects requires special attention to the modelling of waterdepth wind waves and current. Due to the large water depths vessel displacements are large and coupling and interaction effects are strong. A year of experience in this field in the new deep water Offshore Basin of the MARIN (Maritime Research Institute Netherlands) is discussed with projects such as Unocal's West Seno TLP in 1000 meters waterdepth the Bonga FPSO and SPM in 1000 meters water depth for Shell and SBM and the Deepstar Theme Structure model tests (SPAR TLP and FPSO). The focus is on the experience and critical points in the modelling of environmental conditions for deepwater model tests: current wind and waves.

Antarctic krill Euphausia superba are the basis of the ecosystem in the Southern Ocean and the target of a large international fishery. To support management strategies for the resource surveys of krill dispersion and abundance are carried out using multi-frequency echosounders. Estimates of krill TS (target strength) are used to convert the total backscattered acoustic energy attributed to krill into an estimate of krill abundance. The accuracy of the biomass estimate is directly proportional to the accuracy of the TS estimate. Krill TS depends on the animal size shape and morphology and the acoustic wavelength and angle of incidence. Recently a SDWBA (stochastic distorted wave born approximation) model was proposed to improve TS estimates for Antarctic krill. For general application parameterisation of the SDWBA model is improved to account explicitly for dependence among four of the model parameters: standard length of krill number of cylinders used to describe its shape amplitude of inter-element phase variability and acoustic frequency.

In this study the surface of the hollow cavity region behind the dry transom is replaced by a flexible appendage whose shape is derived from the steady flow problem. The final shape of the appendage is determined by means of an iterative numerical scheme of study concluded when the atmospheric pressure and kinematic conditions are satisfied on the modified flexible appendage. This final shape of the flexible appendage is used in the subsequent calculation of the steady flow potential and its first and second derivatives using a Kelvin wave-making source potential method. The linear body boundary condition for the unsteady motions' problem is then calculated using the full m-terms. The method is applied to predict the heave and pitch motions of the NPL mono-hull inregular head waves for a forward speed corresponding to a Froude number of 0.53

A numerical shape optimisation has been carried out on a tanker ship hull using computational fluid dynamics (CFD) techniques and experimental validation. Total resistance and wave patterns were used as objective functions and three different algorithms for the optimization process were tested coupled together with a CFD flow solver. A perturbation surface has been used to modify the shape of the hull allowing for a sharp reduction of the number of design variables. Using different objective functions and geometrical constraints several new optimised shapes have been obtained. Two of these were built and tested in the INSEAN towing tank where the measured data confirmed the optimisation process.

Ship owners and operators are faced with the need to operate sophisticated vessels with lean-manning levels. Changing customer requirements in advanced marine applications and the impact of these trends on a major supplier of marine systems are outlined. The development of advanced Platform Management Systems in support of cost reduction and lean manning is reviewed in more depth with special attention given to the role of human factors and simulation. After some background information a look is taken at key market drivers. Next human considerations are addressed followed by multi-role simulation methodology. Lastly the Submarine Machinery Controls Technology Demonstrator (SMCTD) is looked at.

In this paper the applicability of stochastic finite element method to the in-service reliability analysis of offshore jackets is discussed. The methodology basically involves the formulation sensitivity matrix of the structure using conventional stiffness matrix based on mean values and the variations. The Taylor Series Expansion Technique is used involving the single inversion of a large matrix in order to evaluate all sensitivities. It has been shown that this methodology is computationally less taxing than Monte-Carlo Simulation which involves numerous repetitions of conventional structural analysis involving inverses of large matrices . An existing offshore jacket of 1OOm length is taken as a vehicle for the illustration of this methodology.

In recent years OFS (optical fibre sensors) have experienced rapid development finding applications mainly in gas and oil monitoring. This is thanks to the possibility of distributing various parameters measurements over long distances. More recently a new OFS system has been proposed which uses FBG (fibre bragg gratings) as sensing elements to monitor physical parameters relevant to the management of sea water e.g. temperature and degree of salinity. The proposed configuration shows significant potential for the monitoring of marine bio-environments but suffers from poor robustness of the sensor heads. Here the viability of a multi-plexed 3D sensor network based on a similar OFS technology is experimentally demonstrated with particular emphasis to the design and conditioning of the sensor heads and with the concern of using as far as possible commercially available photonic components (for a large part telecommunications components).

The paper presents an effective way of incorporating the human organisational and management factors in order to improve integrity of offshore marine operations. The aim of the paper is to establish safety barriers and integrate human organisational and management factors into these barriers and define performance shaping factors that could erode the barrier function. This can be achieved by using bow tie analysis. Furthermore the quantification of the risk model if required can be achieved by direct application of human reliability methods for operational errors and by defining the failure rate multiplier based on the assessment of management and organisational characteristics.

Aeromonas spp. opportunistic pathogens of humans and fish are to be found everywhere in the aquatic environment. Aeromonas hydrophila and Aeromonas caviae have increasingly been isolated from patients with gastroenteritis and superficial wound infections and the former also has been associated with haemorrhagic wound septicaemia in fish. This is the first study to report Aeromonas occurrence and frequency of virulence factors in the aeromonad coastal population and individual isolates in Southern California. Quantitative PCR is used with dual-labelled probes to increase the sensitivity in the detection of cytolytic enterotoxin or hemolysin genes and serine protease genes (sp) over MPN single PCR assay in population-based studies on Aeromonas spp. The prevalence of toxin genes in Aeromonas population is determined by detecting the gene copy numbers of the toxin genes per genome. Also determined are the gene copy numbers of this toxin and its activator per genome in pure cultures of environmental isolates. Methods are presented followed by results and discussion.

Anisakis simplex larvae were counted in the body cavity of Baltic herring sampled in the southern Baltic in 1992-1993 1995-7 and 1999. Generalized linear models (GLM) were used to model the prevalence and intensity of infection as dependent on year quarter area length condition factor sex and stage of gonad development. A binomial error distribution was assumed for the prevalence and a negative binomial distribution for infection intensity. A look is taken at material and methods. After this results are considered covering prevalence and intensity. This is followed by discussion.

NAVOCEANO has recently updated its survey vessels and launches to include the latest generation of high-resolution multi-beam and digital sidescan sonar systems along with state-of-the-art positioning attitude and ancillary sensors. This has resulted in a tremendous ocean observing and mapping capability. However these systems produce massive amounts of data that must be validated prior to inclusion in various bathymetry hydrography and imagery products. It is estimated that the amount of digital data to be processed will increase by an overwhelming 2000 times above present data quantities. In order to meet this challenge NAVOCEANO has embarked on a series of hardware and software improvements. This resulted in a significant improvement of the handling capacity of the data volumes. However the key to meeting the challenge of the massive data volumes was to change the approach that required every data point to be viewed. This was achieved by replacing the traditional line-by-line editing approach with an automated cleaning module and an ABE (area-based editor) integrated with COTS (commercial off-the-shelf) software packages.