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The EDP (extended draft platform) concept has been developed by Technip in response to a need for an easily deployable drilling-recovery vehicle in deep water. It has been designed with industry and NSF support to provide substantial power and bandwidth to the seafloor and a stable surface platform for instruments and communications. Originally planned for multi-year deployment at a mid-Atlantic site for multi-purpose measurements (swell meteorology aerosols seismology ocean basin heat content and detailed ocean structure) the prototype will first be tested in Malaysian waters. This deployment will generate early science results and provide a testbed for power generation platform performance communications and sensor technologies. The EDP comprises three vertical columns between a triangular deck structure and a submerged pontoon. The columns and pontoon are raised when at quayside and during towing. When lowered the structure behaves like a deep draft semi-submersible and motions are comparable to those of a spar buoy. The EDP will have a draft of about 23 m and the deck will be over 10 m above the sea surface. It will weigh 800 t and be able to support payloads of over 50 t. An offshore supply vessel assisted by a small offshore tug can install the EDP while a ROV equipped vessel would install the EO (electro-optic) cable and the seafloor instrumentation. It is designed to generate 10 kW of power on the platform and deliver 500 W to seafloor instruments through the EO cable. Substantial communications bandwidth will be provided by C-Band satX16599

BP's Harding development employs an innovative concept for North Sea oil production. A large permanently installed jack-up platform incorporating production drilling and living quarters is positioned on top of a concrete gravity storage base tank which holds Harding's acidic heavy crude before export to shuttle tankers. The use of horizontal drilling techniques in the early 1990s coupled with adoption of the above concept transformed a very marginal prospect into a viable development which currently has one of the lowest development costs per barrel in the North Sea. The viability of the development has been achieved using an entirely new approach to project management with a small integrated management team. The relationships created with design contractors suppliers and fabricators are shown to represent the embodiment of the principles of the CRINE (cost reduction in the new era) initiative and have secured for all parties benefits which can be used as benchmarks for future projects in a low oil price environment. Contractual arrangements are discussed and a new approach to operations and maintenance support contractors is highlighted. The concept has potential for reducing abandonment costs due to the relative ease of decommissioning and removal.

Since the introduction in 2002 of the International Management Code for the Safe Operation of Ships and Pollution Prevention (ISM Code), and the 1995 revision of the 1978 Convention on Standards of Training Certification and Watchkeeping for Seafarers (STCW Code), questions have been raised about whether it is possible to develop a safety culture in a fragmented, global industry and what effects the diversity of cultures might have upon implementation of the ISM Code. This study explores those questions. Subsequent to a review of the literature, a model of the working of the ISM Code is developed and used to identify the constraints and pressures, particularly those that might be influenced by cultural values and attitudes, that impact upon the development and implementation of a Safety Management System in individual shipping organisations. From analysis of the data the study concluded that professional, vocational and safety training correctly utilised are effective in harmonising culturally influenced safety perspectives, thus improving safety performance; and culturally influenced constraints and pressures can be dealt with by the application of standard management techniques which, in a multi-cultural environment requires good cross-cultural management skills.

As a first phase in its decommissioning the Maureen Alpha Steel Gravity Base platform was refloated from Block 16/29A on the UK Continental Shelf to Norway in late June 2001. In order to carry out the decommissioning approval had to be obtained from the UK Government of a Decommissioning Programme to be executed in accordance with the UK Petroleum Act 1988 and its Decommissioning Guidelines. The following are considered: discussion of drilling history; long-term monitoring; recovering of species diversity; links to industry study work; peer and academic review; disturbance modelling; environmental modelling and the actual disturbance of cuttings at the time of refloat. The availability of historical data over the life of the field allowed the owners to develop an acceptable strategy for the long-term management of the drill cutting accumulation within the Platform Decommissioning Programme. Supported by emerging information from the industry studies of drill cuttings and the demonstration of effective measures to deal with all environmentally sensitive activities an overall plan was constructed. The programme received rapid acceptance from the UK regulator and stakeholders.

An overview of the North Caspian Project is presented. This is the first exploration project in the North Caspian. The Caspian Sea represents the biggest inter-continental basin in the world. The North Caspian is shallow in particular the eastern part. The technical solution for the first drilling exploration in the North Caspian is briefly introduced. The drilling barge Sunkar (Parker Rig 257) was designed to withstand extreme ice forces and high reservoir pressures and also to cope with a highly poisonous corrosive hydrogen sulphide gas. As the barge is drilling in a nature preserve zone the highest engineering standards have been used. The drilling program started in 1999. The technical and commercial understanding of the realistic oil potential of the North Caspian Basin is described i.e. by 2010 the Caspian should be exporting some 3 million barrels a day two thirds from the North and one third from the South. In the longer term the North Caspian production could potentially even reach 4 million barrels in 2020. The forward speed of Caspian energy development still is heavily dependent of a sustainable $20/bl oil price plus and of material improvements in both infrastructure and financing risk. In the North Caspian successful disposal of material volumes of associated gas cap gas into Russia will also dictate the pace of these new oil developments. Continued pressure by Caspian governments on energy investors that would undermine the integrity of their Production Sharing Contracts will erode long-term investor confidence. The Caspian would then become substantially less competitive for global capital with all consequences. The evaluation of the political and development risks forX35601 The North East Frigg Field installations decommissioning

The need for the use of risk assurance technology has been identified by P&O / Princess Cruises as a means to better manage their business. A risk model has been developed to implement a proactive risk management strategy. The main reasons to develop a generic risk based model for a large cruise vessel were to improve the performance of the current fleet to learn from experience in the field and to provide a mechanism for predicting loss scenarios. Because of Princess Cruises' view of risk assurance as a strategic tool it was decided to base the risk model on a top down approach. Development of the model is discussed with reference to the reference framework development of the vessel operating structure chart hazard identification translation of the risk model into practical design information management of the model incorporation of field experience identification of design modification and interface with fleet regulations. The model is designed to interface with the design building operation and disposal of a vessel. Further development of the model is projected and this is described together with how the risk based work interfaces with Princess Cruises' well established ship and shore based management procedures.

The Hudson-Raritan Estuary and the New Jersey Atlantic Ocean shoreline are densely-populated regions that provide significant economic environmental and recreational benefits to the States of New York and New Jersey and to the US nation. Issues confronting the region include safe navigation and maritime security within one of the largest ports in the world water quality concerns and beach erosion and flooding along the heavily-populated New Jersey and Long Island shorelines. Since 1998 Stevens has been developing a network of operational coastal ocean and estuary sensors that provide realtime observations of weather and ocean conditions throughout the region.As the network has expanded and experience has been gained in the operation of the sensors and in the specialised needs of the array of data users the system has evolved significantly. A forecasting component has been added and 48-hour forecasts of weather and ocean conditions throughout the region are provided via the Internet. The modelling system is based on a high-resolution version of the Princeton Ocean Model. The model employs advanced data assimilation algorithms in order to optimise the use of the real-time ocean and weather data in the forecasting system.

The sediment in mangrove swamps is highly impermeable and therefore greatly impedes the transport of porewater solutes. Subterranean animal burrows provide an alternative pathway by which porewater can be conveyed to and from deep within the mangrove substrate. Burrows have been observed to penetrate up to 1.2 m and greater into the mangrove sediment. Subterranean burrows in mangrove swamps may be located in situ by use of an electronic probe. An array of ring electrodes mounted on a rod provides an effective means of measuring the apparent electrical conductivity in sediment. The variations in the conductivity indicate different sediment characteristics. The probe is used to locate voids in the sediment; i.e. burrows formed by animals. One the burrows have been located samples of the burrow water are extracted for testing. The concentrations of dissolved nitrogenous compounds and of salt are determined to investigate the tidal flushing of the burrows. The concentrations of nitrogen-based solutes compare favourably with previous studies and show little variation with depth. The salinity data support the hypothesis that significant mixing of burrow water occurs throughout the entire depth of the burrow. Methods are described and results are presented.

The raising of the Mary Rose in 1982 made headline news. As an archaeological event it ranked alongside Schliemanns excavations at Troy or Arthur Evanss discovery of Knossos, and so much information has since been gleaned from the wreck and its contents that there is an overwhelming tendency to treat the ship as a "time-capsule", like some Tudor burial site. But the Mary Rose is not just an archaeological relic. She is a warship that was revolutionary in her time and, despite being most famous for her loss in battle, a ship that had served her monarch for 34 years, almost the length of his reign. This book tells the full story of the construction and career of the ship, placing it firmly within the colorful context of Tudor politics, court life and the developing administration of a permanent navy. However, it also brings the story down to the present day, with chapters on the recovery and the new ideas and information thrown up by the massive program of archaeological work since undertaken. Written by the Development Director of The Mary Rose Trust and heavily illustrated from the massive resources of the Trust, this is a book which will appeal to general reader and specialist alike.

The assembly process in shipbuilding essentially involves the joining of large blocks. These blocks are typically all-welded thin plate structures. During the fabrication of these blocks distortions occur due to a variety of causes including the cutting and the welding. Even through it is practically impossible to eliminate distortion completely it is necessary to produce blocks with a sufficient level of accuracy so as to avoid problems in the course of assembly. Local shrinkage is produced as an unavoidable consequence of welding. While this shrinkage is the major cause of the geometrical error in the welded structure there are many other contributing factors that cannot be ignored such as initial geometrical error in the parts root gap of the groove positioning and fixture prior to welding. The welding sequence is one of the major contributing factors to the root gap and the misalignment and hence to geometrical accuracy. Generally there are two major causes of geometrical error in the welded structure. The first cause is local shrinkage due to the thermal cycle experienced in the weld zone. The local distortion can be divided into three categories namely longitudinal shrinkage transverse shrinkage and angular distortion. All three types are strongly affected by heat input shape of penetration plate thickness and joint type. The second cause is the gap and the misalignment produced in the joint prior to welding. Contributing factors on the gap and the misalignment are the welding sequence

Intermittent riser VIV behaviour caused by vessel motions can affect both riser strength and fatigue life. Frequency domain codes are available that are used routinely to calculate riser fatigue damage from VIV due to currents. These codes are often adapted to calculations of the vessel motion VIV and fatigue damage. The adaptations reduce the intermittent VIV to steady state VIV by assuming an appropriate time invariant velocity profile over the length of the riser. However since vessel motions cause a relative velocity profile over the riser that varies with time and the VIV response is intermittent a time domain VIV code is best suited for such an analysis. The use of Technip's time domain riser VIV code ABAVIV is demonstrated to calculate steel catenary riser VIV response and fatigue damage due to vessel motions. Since time domain analysis is computer-time intensive an efficient methodology to perform these calculations is also outlined. The analysis example in the paper is based on surge pitch and heave motions which are the most important vessel motions for the riser fatigue damage near the touch down region. The ABAVIV code accounts for the non-linear structural characteristics of the SCR and the unsteadiness of the VIV phenomenon for the present application.

A trimaran concept for offshore operations has been developed. Vessel features include low response in waves low resistance for efficient transfer over long distances launching positions for intervention equipment and a large deck area. The vessel may in different versions represent an interesting design to be used for field development and for inspection maintenance and repair in Northern Seas. Efficiency in operation has been focused on in the development of this concept. To build a vessel for the future one has to study where the industry is moving and where likely work will be coming up in the future. Advances in technology both in ship design and in subsea intervention are hard to predict and the capacities and characteristics for the future are hard to foresee. Some characteristics are however likely to be desired in the future as well. These are characteristics such as low vessel motions good fuel economy a large deck area and high loading capacity to name but a few. These characteristics are in turn perhaps not easy to combine. One vessel concept that combines some of these features in an elegant way is the trimaran. Concept development and theoretical analysis were followed up with tank testing. A 1:50 scale model was built and tested in a 60 m towtank. Resistance and Motion tests were carried out and compared with computer analysis. Comparison of results shows good consistency between analysis and tank tests.

There has been a global drive for renewable energy research and development. There are a number of renewable energy sources: wind power solar hydrogen electric geothermal biomass and marine energy. Tidal energy is a form of hydropower which concerts the energy in the tide into electricity. Tidal energy systems can further classified into two groups: tidal barrages which make use of the potential energy in the different in height between the high and low tides and tidal current systems which make use of the kinetic energy in the ebb and flood flow to drive the turbines. Tidal current energy conversion is reliable and has minimal negative environmental impact is cheap and continuous and is not weather-dependent. Scottish enterprise has estimated that about 34% of UK electricity demand can be produced from tidal currents; this signifies a huge untapped resource. A typical tidal current energy system is a simple system comprising a tidal turbine supported on a structure positioned to extract the kinetic energy of the ebb and flow of the tides. An electrical grid connected system allows for the supply of electricity to consumers. The area of interest is the tidal turbine and its support structure fully submerged in high-density flow seawater. A typical site for a tidal current energy device is a challenging environment

Oil and gas operators and their suppliers reported skills shortages in the key occupations of geologists geophysicists and subsurface-reservoir engineering. Sub-sea UK also reported deficiencies for highly qualified and experienced engineers. The lead-time to 'produce' an appropriate individual (right technical degree additional expertise etc) for the operator and sub-sea sectors requires long-term planning based on sound information and intelligence. The objectives of the research were to: understand the key factors which contribute to identified problems of the availability of people to carry out jobs-roles in geology geophysics and sub-sea engineering; evaluate the current provision within the learning supply chain; capacity; capability and current action; assimilate information from employers and learning providers such that recommendations can be made to improve agreed issues and challenges. The findings are reported and recommendations are made.

The new Freon-free international standard for oil-in-water analysis EN ISO 9377-2 was formally accepted in October 2000. The method is described. External calibration is used for quantification. The technical robustness of the new method is examined. This has been demonstrated through a number of validation studies and by inter-laboratory exercises. The historical robustness is also addressed. The method has been recommended by the Norwegian State Pollution Control Agency as the new reference method for oil-in-water. OLF (the Norwegian Oil Industry Association) and IMO have tested the method and suggested it for the analysis of discharges from oil-producing platforms in the North Sea and for the analysis of discharges from ships (bilges). Further discussions are going on in OSPAR about the possibility of including volatiles and monoaromatics (BETX) in the same analysis. The problem is where to set the lower limit of the method related to the hydrocarbon boiling point and also the need for detecting aromatics (including polyaromatic compounds) by more specific methods (GC-MS). Certified oil-in-water samples may be available in the future through an EU project that will be initiated in 2002.

Advances in underwater networking will accelerate if researchers are able to re-use software frameworks and interfaces to the physical layer as is done in terrestrial cabled and wireless networking. The most common development paradigm in use today is custom-written software that is normally not available to others to use as a starting point. In addition network researchers that develop software targeted at a specific physical layer may have difficulty porting network software to other modems if the interface is not generalised with a driver to create a generic device. A modular open-source software architecture has been developed and demonstrated for simple ad-hoc networks. While the initial implementation includes and uses an interface to the WHOI Micro-Modem the system is intended to be device-independent in order to allow network researchers to write code that can be run on multiple hardware platforms. Its main function is to provide an architecture that allows easy plug-in of specific link-layer functions such as MAC (medium-access control) and modem-specific physical layer interfaces. An in-depth overview of the software architecture and its mapping to network functionality is included plus initial results of a simple ad-hoc network created as the initial implementation example. While time will tell if this will be successful this first step is key to starting a process that will involve multiple institutions and projects and advance the state of the art in underwater acoustic networking.

Limitations in our current knowledge of a ship in extreme wave conditions have been illuminated by the work being done by the US Navy on advanced hull-forms. Stochastic approaches to these phenomena are insufficient and deterministic testing of these events must be carried out if the physics is to be understood. Although modern computer controlled wavemakers provide the ability to generate regular sine waves long crested multi-spectral waves mixed seas of almost any sea spectra and even 'freak' waves all of these systems require the wavemakers be tuned to the specific facility and that transfer functions between wavemaker settings and the generated wave be calculated. This tuning is carried out to compensate for the facilities geometry wave absorbers (beaches) etc as well as to aid the researcher in using the wavemaker system. The MASK (manoeuvring and seakeeping) basin at the NSWCCD (Naval Surface Warfare Center Carderock Division) is a large rectangular basin measuring 240 feet (73.2 m.) by 360 feet (109.7 m.). Two adjacent walls of the MASK are equipped with pneumatic wavemakers while the other two banks are equipped with wave absorbing beaches. This paper describes the development of a feed-forward neural network model of the MASK wavemakers and demonstrates the utility of this approach in calibrating wavemakers and generating wavemaker transfer functions.

A study was set up to examine the inter-relationship between water-quality determinands and to identify the spatial controls upon water quality at a regional scale. The study was to help fill a research gap of a regional river study in Hong Kong to provide a basis for contamination-abatement and to help formulate a better management plan for the local river environment. A six-year river data water quality set obtained by the HKEPD (Hong Kong Environmental Protection Department) at 82 monitoring sites was used to study at a regional scale the spatial controls and influences upon water chemistry in HK rivers. Univariate statistics and factor analysis of the elements were applied to analyse 27 determinands of surface water quality. The results are presented and discussed. The statistical results show that nutrients aggregate organics and metals have greater variation than physical parameters which are less influenced by anthropogenic factors. These determinands can also be explained by four principle factors representing nutrient and organic contamination marine influences and heavy metal contamination. Finally the local rivers can be classified into four groups based on the factor scores derived from the factor analysis. These results may contribute to the improvement of land-use planning and sewerage design in the future.

Spar platforms have been in service in the Gulf of Mexico since 1996 for combinations of production workover and drilling applications. They resemble a cylinder and when exposed to a steady current shed vortices from one side to the other resulting in pressure oscillation which causes VIM (vortex-induced motion. VIM has serious consequences on the fatigue of mooring and riser systems and suppression is achieved through helical strakes which disrupts the formation of vortex. At present there is no analytical means of predicting the effectiveness of strake design other than resorting to long and costly experiments conducted in model basin. An alternate approach is explored which uses numerical methods in CFD (computational fluid dynamics) currently being investigated by many researchers. Investigation of this approach is presented here by comparing the transverse vibration of a spar (truss spar) selected from the direction which produced the largest vibrations in the experiment for a range of currents. This approach is well suited for flows where small scales transmit a notable amount of energy to larger ones. The flow simulation is compared with experimental data from a model test.

The use of fixed stator blades either upstream or downstream of the propeller has been recognised as a means of reducing the rotational losses behind a propeller thereby yielding a higher propulsive efficiency. The use of ducted propellers has often been an attractive alternative for ship and underwater vehicle propulsion as well. Ducted propellers have been used both to protect the propeller and to increase propulsive efficiency or to reduce propeller cavitation. A method is developed to analyse the flow around a ducted propeller operating in combination with a set of pre-swirl stator vanes. The method uses a boundary element method to solve the flow around the duct and the hub and a lifting surface vortex lattice method to solve the flow around the propeller and the stators. The 3D flow around the duct-hub propeller and stators is computed separately with the interactions between them being accounted for in an iterative manner. The interactions between the duct and the stators and between the duct and the propeller are treated in a non-axisymmetric manner. However only the circumferentially averaged interactions between the propeller and the stators are considered. Using this method a duct and set of stators are designed to operate efficiently with an existing propeller. This model was then built and tested in the MIT water tunnel at a variety of stator pitch angles. Comparisons are made between the theoretical and experimental values for the forces on the duct propeller and stators. A very good agreement is achieved in the region of attached flow.