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Sea Surface Temperature (SST) is required by operational ocean and atmospheric forecasting systems to constrain the modelled upper ocean circulation thermal structure for exchange of energy between the ocean and atmosphere and for validation of model output. The Global Ocean Data Assimilation Experiment (GODAE) is an international collaboration for ocean forecasting activities which in 2002 initiated a GODAE High Resolution SST Pilot Project (GHRSST-PP) to address an emerging need for more accurate high resolution sea surface temperature (SST) products. GHRSST coordinates the harmonisation of a wide variety of SST data streams from satellite and in situ sources that are shared indexed processed quality controlled analyzed and documented within a Regional/Global Task Sharing (R/GTS) framework implemented in an internationally distributed manner. GHRSST-PP data management teams continue to refine the data management structures to provide a functional system that conforms to international and federal directives. The GHRSST-PP International Project Office jointly funded by the European Space Agency and Met Office UK continues to manage the international co-ordination of the project. This paper reviews the progress of the GHRSST-PP highlighting achievements that have been fundamental to the success of the pilot project. The current status of the follow on Group for High Resolution SST (GHRSST) is presented which aims to pull through the pilot project successes into a sustainable system for SST.

The LNG industry is growing at a rapid pace and medium- to long-term forecasts predict a shortage of LNG supply in a few years' time. With the huge amount of stranded gas fields and associated gas the introduction of offshore LNG production or as it is often referred to the FLNG (floating LNG) can reduce the gap between supply and demand. The FLNG is a floating ship-shaped vessel that can produce LNG condensate and LPG from stranded and-or associated gas fields offshore. FLEX LNG has four hulls on order and has an EPCIC contract for the topsides of the first vessel. The final design is neither an evolution from the LNG shipping industry not the Offshore Oil & Gas industry nor is it a marinisation of a land-based liquefaction plant but rather it is a dedicated unit combining the best of these industries. This paper describes the design process and the resulting basic design. Particularly the generic character of the design is described and the adaptability to serve a large range of gas fields with all kinds of project- and client-specific requirements and conditions. The paper helps both engineers and project developers to consider floating LNG production for a given offshore or onshore gas field.

In ship structures the strength of rectangular plate elements is extremely important for the overall strength of the ship. The possibility of using panel models equivalent to single rectangular plate models under in-plane compression loads was investigated in order to allow future studies about isolated effects on plates. The strength of panels composed of three and five plates connected transversely and loaded along the longitudinal direction is considered. First a comparison between the strength of panels having asymmetric imperfections and of single plates is made which allows the ability of the single plate to properly simulate the panel strength to be evaluated. Following this the results obtained for a panel model having symmetric imperfections are compared with the results of the asymmetric imperfections. The asymmetrical and symmetrical models of the panel give respectively the lowest and highest strengths possible (imperfections in adjacent plates with different amplitudes have 'in between' strengths) allowing limits to the variation of the strength to be established. The results show that using a single plate can be conservative or non-conservative depending of the plate slenderness and shape of initial deflections. It is concluded that for design purposes it will in general be enough to consider assemblies of three plates as the results for five plate assemblies are not much different

The current major design practice for permanent taut mooring systems leads to large suction installed piles suitable for very soft clays that are common in West Africa. These suction piles are expensive to build and to install requiring a large installation vessel with significant deck space and lifting capacity. For these reasons SBM has undertaken a large R and D program to develop a plate anchor called the VELPA (vertically loaded plate anchor). This is pushed to target-known depth by a new installation tool called the Pyrodriver developed by the sister company IHC Hydrohammer. Extensive Laboratory centrifuge and onshore tests have first been carried out with the VELPA. Three full scale VELPAs (4 8 & 12 m squared) have been made and tested offshore West Africa in a water depth of about 450 m. The testing is described. After this the Pyrodriver is described. This is a tool to push an anchor into the seabed. There is no need for a large diameter umbilical or hoses from surface to Pyrodriver. The fuel in the Pyrodriver is based on nitrocellulose in pellets and is a very slow burning propellant. This also makes it relatively safe to transport because it will never detonate. Water is the main component of the reaction mass.

Acoustic surveys are used in 20 stock assessments within the ICES community and almost all as relative indices of abundance. The North Sea herring acoustic survey started in 1979. In this paper the precision of the survey is estimated using data at ICES statistical-rectangle level from 1989 to 2001 and bootstrap-resampling methods modified by geostatistical estimates of the spatial autocorrelation. Similar techniques are applied to the larvae Methot and trawl surveys that provide the other data on North Sea herring. The comparison of survey performance is also examined using the bootstrap estimates of abundance to give 1000 simulated assessments of North Sea herring using the integrated catch-at-age (ICA) method. The results of these analyses are compared and the weighting of the various indices within the assessment is investigated. A weighting method is presented that provides a more precise method for estimating the stock. The more precise assessments are compared for retrospective pattern. An assessment is proposed which provides the most precise stock estimates with the best retrospective pattern. The importance of the acoustic survey and its contribution to the assessment in relation to the other indices is discussed.

The book is based on 'Practical Yacht Construction' by C.J. Watts but is a revision due to the changes covering the whole field of yacht construction. It uses the original framework. Chapters 1 and 2 cover construction of keel, hull, decks and other parts but includes glues for main structural members and of plywood for decks, changes in metal fastenings etc. Chapter 3 covers engine seating, anchor arrangements, davits, cavils, stern chocks or archboards. Chapter 4 covers masts and rigging, with changes from gaff rig to the more efficient Bermudan rig and the introduction of aluminium masts, stainless steel standard rigging etc. Chapter 5 covers joinery work, plumbing, heaters, steering, ventilation, electric equipment and auxiliary propulsion. Lighter, more efficient joinery, better plumbing systems, plastic piping and improved ventilation have been introduced. Chapter 6 covers Thames tonnage, inside ballast, general arrangement, winches, pulpits and other fittings. Chapter 7 deals with the emergence of the glass-reinforced plastic hull, covering materials, moulds, methods of construction and notes from Lloyd's Rules repairs. The final chapter covers the introduction of special ship building alloys and a comparison with more traditional steel or timber construction.

Recognition of real time locations of crews for a naval ship is important not only for the operation efficiency but also for the safety of onboard crews in the ship. More than 100 crews live on a modern naval ship and they are involved in various duties. Moreover many visitors come in and out frequently while the ship is moored in a harbour. It therefore sometimes requires considerable time and effort to find a person for an urgent mission. It would enhance the operational efficiency if the location of onboard crewmembers was recognised and monitored in real time. An active type RFID tag which has a specific ID number is distributed to each crewmember and this should be carried during his stay in the ship. A number of fixed type RFID readers are to be located at the major passages of the ship which are connected to the main computer via he LAN (Local Area Network). The location of a crewmember would be identified by the ID number of his RFID tag and the location of the RFID reader which detected the RFID tag. A middleware is needed to process the collected data in the main computer. The data is fed to application software which actually displays the location of the crewmember concerned. The software is coded using GUI (Graphic User Interface) for better user friendliness which has the function of storing the location history of a crew and sending warning messages to appropriate persons if unallowable behaviour is deteX44635

The Barataria Basin a bar-built estuarine system has been experiencing a significant land loss especially since the leveeing of the Mississippi River for flood control purposes in the early 20th century. Recent efforts to alleviate the land-loss problem include the construction of man-made freshwater diversion structure in order to divert river water as well as its associated suspended sediments from the Mississippi River into the Barataria Basin. In order to implement an ecologically friendly management plan of those diversions a careful examination of the anticipated salinity alterations resulting from the operation of the diversions is required. A high-resolution integrated hydrology-hydrodynamic model of the Barataria Basin has been developed to simulate the local hydrological cycle over the surrounding drainage basin and hydrodynamics within the basin. A flood event due to the tropical storm Allison in June 2001 provided a rare opportunity to test the model. The integrated model appears to be able to capture a significant portion of the observed sea-level variations during the flood. Model simulation run for the summer of 1999 suggests that significant effects on water level and salinity are observed in the multiply connected channels through the marsh in the vicinity of operating diversion structure and in the open waters downstream. Some issues remain concerning the importance of 3D effects in such shallow systems and the specification of open boundary conditions. Verification studies are continuing. A verified and calibrated integrated model will be useful for simulation of s95351 High-resolution interferometry for multi-beam echosounders Gerard Llort Pujol ; Christophe Sintes ; Xavier Lurton

A research program is being developed to separate advanced methods for the design of high-speed vessels in aluminium alloy. The evolution of structural design in this field has led to the application of new construction technologies especially the use of aluminium which is particularly suitably for small and medium coastal shipping fast ferry design. The structural design process for such ships must satisfy the requirements of strength analysis and structural optimisation of weight. An investigation into the preliminary monohull fast ferry subdivision compatible with the new IMO HSC (high-speed craft) codes has been developed. A first step general plan has been drawn up based on the HSC2000 rules and a first structural morphology has been proposed. A preliminary analysis has been developed for the aluminium monohull structural design. Thin-walled beam theory when opportunely applied can be a valid design tool for the primary structural response. The FE (finite element) technique has been applied loading the entire hull structure with a rule regulation equivalent wave and with an inertial vertical load. An aluminium bottom-stern stiffened panel has been extracted to analyse in a finer way the structural response under a slamming load. The results show that the scantlings deriving from a regulation assessment and finally verified by the direct calculation are largely sufficient to ensure the structural capability also if an inertial load is applied.

A major impetus for scientific studies of climate change in the Arctic Ocean has been the reduction in the areal extent and thickness of its sea ice cover. An extended measurement record of the horizontal dimensions of this ice cover is available for the full Arctic Ocean Basin based upon a record compiled from more than 30 years of relatively continuous satellite based measurements. Unfortunately data accumulations for the ice cover's vertical dimension ie sea ice thickness tend to be limited to data sets with durations no longer than 15 years reflecting underlying greater measurement difficulties. Moreover the longest duration ice thickness data collection efforts have been confined only to two specific portions of the Basin namely Fram Strait and the Canadian sector of the Beaufort Sea. Elsewhere the available data sets are either of notably shorter duration or non-existent. Upward-looking sonar (ULS) has been and continues to be the primary source of data with volumes and accuracy sufficient for meaningfully monitoring ice thickness. Originally deployed from polar-traversing submarines during the Cold War the limited amounts and accessibility of the collected data stimulated development of purpose-built sea-floor moored ULS instrumentation which beginning in the late 1980s began to supply the bulk of newly acquired ice draft and ice under-surface topography data. Technological advances have subsequently led to new generations of ULS instruments including ice-profiling sonar (IPS) incorporating much expanded on-board data storage caX27454

Current IMO regulations require life rafts to be tow tested only in calm water. In real evacuation situations life rafts are deployed in the prevailing environmental conditions with wind and waves. Added wave resistance is small at low wave heights but increases non-linearly with increased wave height. If life rafts are to be towed in moderate seas (up to 4 m significant wave height) tow force estimates based only on calm water tow resistance become less reliable. Tow patches towline towing craft etc. also need to be designed to withstand dynamic wave loading in addition to mean load. Therefore mean tow force tow force variation and maximum tow force are important. A full-scale 16-person commercially available SOLAS-approved life raft was towed in the tank in upwind head seas with significant wave height of 0.5 m. The measured tow force showed that it could be treated as a linear system with wave amplitude by demonstrating that tow force is mainly inertial and follows a Rayleigh distribution. Therefore extreme-value statistics used for waves can be applied to developing equations for predicting tow force. A method is proposed to predict life raft tow force at different tow speeds and in various sea states

Fretting is a process of material damage which results from the rubbing of two contacting components with small-amplitude oscillatory movement. Fretting is known to cause premature fatigue failures in structural elements such as riveted or bolted lap joints steel ropes and cables and the contact region of dovetail joints of gas turbines. In addition to material properties the fretting damage is governed by factors such as contact geometry normal load slip behaviour loading frequency and surface roughness. Fretting results in a scar oxides and debris and leads to material transfer surface plasticity and surface cracking. The possibility of fretting damage in pressure armour wires of flexible pipes has been investigated. A novel experimental facility which is capable of simulating nub-valley contact conditions with dynamic slip representative of actual pipe loading has been developed. The test setup is equipped with a state of the art data acquisition system and a controller with transducers to measure and control the normal load slip amplitude and friction force at the contact in addition to the hoop stress in the wire. Tests were carried out with selected loading and the fretted regions were examined using an optical microscope. Results show that the magnitude of contact loading and the slip amplitude have a distinct effect on surface damage. Surface cracks originated from fretting scar were observed at very high contact loads in mixed slip sliding while surface damage predominantly due to wear was observed under gross slip. The position of surfaX44612

Petrobras is going deeper and some fields are feasible only if the production platforms are installed in ultra deep waters close to the wells. In one case in Campos Basin for example the platform will be installed at 1255 m water depth and the solution to allow the production is based on the evolution of flexible lines for high pressure and high loads. For the oil export line however a steel rigid line was chosen due to the large diameter. Some analyses were performed in order to make feasible the installation of an 18-inch SCR export oil line. Due to fatigue loads the free hanging catenary configuration did not match with API RP 2RD recommendations so Petrobras decided to change the original shape to Lazy Wave in order to reduce the top loads and increase the fatigue life. But some configurations are not feasible to install. This article presents the steps made to reach a configuration that will make feasible the installation of this riser in parallel to the static and dynamic analysis to maintain the stresses in an allowable level in accordance with API RP 2RD.

Petrobras is going deeper and some fields are feasible only if the production platforms are installed in ultra deep waters close to the wells. In one case in Campos Basin for example the platform will be installed at 1255 m water depth and the solution to allow the production is based on the evolution of flexible lines for high pressure and high loads. For the oil export line however a steel rigid line was chosen due to the large diameter. Some analyses were performed in order to make feasible the installation of an 18-inch SCR export oil line. Due to fatigue loads the free hanging catenary configuration did not match with API RP 2RD recommendations so Petrobras decided to change the original shape to Lazy Wave in order to reduce the top loads and increase the fatigue life. But some configurations are not feasible to install. This article presents the steps made to reach a configuration that will make feasible the installation of this riser in parallel to the static and dynamic analysis to maintain the stresses in an allowable level in accordance with API RP 2RD.

During the past few decades the need for electric power and fresh water requirements has turned man to using temperature difference in deep sea around the world. The design of a 0.25 MLD (Million Litres per Day) low-pressure desalination plant in 150 m water depth using a TLCP (tension leg counterweight platform) consisting of a 10 m diameter hull 1 m diameter cold water pipe with counterweight and vertical taut mooring has been carried out. A 1:50 scale model of the TLCP is tested in the 30 m x 30 m x 3 m wave basin. The tensions in mooring lines are measured using load cells. The coupled analysis of the TLCP is studied using the NOAS (non-linear analysis of offshore structures) program developed at IIT MADRAS. The measured tension response of mooring line compare well with numerical results. The Surge Heave Pitch and Tension response amplitude operators for the TLCP obtained from numerical study are observed to be within the permissible limits for the operational wave condition whereas the TLCP performs satisfactorily for the survival wave condition. The numerical and model studies are carried out for regular waves. The effect of counterweight and pretension on platform motions is studied.

Statistical methods are adopted to understand the wind and wave characteristics over the Hsinchu Water where there are three observing pots: the coastal wind station the Hsinchu data buoy station and the Kuokwang oil platform station. Field data from 1998 and 1999 are used for analysis. The wind speeds in the file were measured at the land-based Hsinfung weather station Hsinchu data buoy station and Kuokwang oil platform while the field wave data were measured at Hsinchu data buoy station and Kuokwang oil platform. In order to investigate the variation of wind directionality and wind speed due to the topographic effects in the offshore region near shore region and coastal zone wind rose analysis is firstly applied to the field data measured in different stations. Secondly the comparison of the 3m-wind speed which has been transformed according to the wind profile equation in different stations is carried out. The statistical analysis of waves is mainly focused on the discussion of the statistical wave heights and periods distributions in Hsinchu region. Comparison of wave heights and joint wave heights and periods distributions in different stations are made. Regression analysis and Markov Chain analysis are also made to establish the correlation of wave heights in Hsinchu data buoy station and Kuokwang oil platform.

Roll motion is one of the most important responses of a ship in waves. Potential flow base theories although they reproduce the heave and pitch motions very well are much less effective in predicting the roll motion due to the negligence of fluid viscosity. This shortfall is usually compensated for by introducing a viscous roll damping component. However it is not even simple because of non-linear characteristics due to the effect of fluid viscosity and strong dependence on the forward speed of a ship. Moreover the appendages such as bilge keels and rudders make the problem much complicated. The present study shows URANS (Unsteady RANS)-based approach to simulate the free roll decay motion for a ship. The WAVIS (Ver. 2.0) code is extended to simulate roll decay motion which is originally developed for the predictions of resistance and propulsion performance of a ship in MOERI. The numerical simulation is applied to the DTMB 5512 model ship which has the experimental results obtained in INSEAN (Italian Ship Model Basin) towing tank. Roll decay motions are simulated both at the Froude number zero and 0.138 with and without bilge keels. The results show that CFD-based approach is very promising to predict the roll damping force.

Risk based inspection of process plant is a technique where inspection is concentrated on those areas which are most likely to fail and create problems if they do. The type of inspection carried out is in direct relation to the anticipated failure mode. In 1994 British Gas determined that the application of a risk based inspection approach to the two installations in the Rough Gas Field would have several benefits including improved operational efficiency. During 1994 and 1995 British Gas and the author's company worked closely together to implement the riskbased inspection approach in the Rough Field. This has required (1) the preparation of written schemes of examination; (2) an authoritative review of the pressure systems including the assignment of grades and conditions to all of the piping and pressure vessels; (3) an Operational Critically Assessment of all piping and vessels to determine the consequences of failure probability of failure and the failure mode for each item; (4) development of new inspection schedules and intervals; (5) development of a review and feedback system so that inspection results may be used to alter the grades of piping and equipment and the subsequent inspection intervals. This development has been agreed with the certifying authority and has resulted in some inspection intervals being greater than the traditional five year certification limit.

The Global Ocean Data Assimilation Experiment (GODAE) has addressed the necessary technological development for data assimilation which is a critical choke point within the process of providing meaningful information to many people encompassing a wide range of applications. One of these application areas is for Navies throughout the globe. Major use by operational Navies of oceanographic information through numerical model forecasts initialized by analysis of global satellite and in situ data sets has allowed substantial advancement in the safety of operations and search and rescue. The importance of the information relayed to ships across the globe is reflected in the dedication of large resources to daily production and dissemination. Not including the costs of observational systems there are large investments associated with personnel required to ensure that each step of the processing is properly conducted every day. The communications and computational hardware requirements to ensure products are delivered require enormous effort and costs to implement. The importance of the information on which decisions are made daily by the worlds Navies throughout the worlds oceans is reflected by the commitment of these substantial resources to ensure the GODAE technology enables a new level of capability. Some of the major applications that are common throughout Navies of the globe are examined in this paper.

The Pacific Ocean Shelf Tracking (POST) array was initially conceived and planned as a single continental scale acoustic tracking system for direct measurement of the marine movements and survival of animals in the ocean. With the success of the demonstration phase POST is now transitioning into a single integrated global system of compatible arrays distributed throughout the continental shelves of all continents. In summary POST has demonstrated that a large-scale system to track fish in the ocean is feasible. Equally important the fates of multiple fish stocks (migration routes and speed of movement plus survival) were simultaneously accounted for during their downstream and early ocean migrations demonstrating that the system can be made economical because of its ability to support many studies at once. Having demonstrated the technical feasibility and biological importance of the data collected POST's near-term goals are to deploy units that can permanently stay on the seabed for long-term monitoring along the continental-shelf and to increase the scientific understanding and need for the information that will be collected.