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Nowadays the cavitation of the rudder system is frequently observed because cargo ships such as container ships are bigger and faster. Damage to the rudder system due to cavitation is mostly observed around the leading edge and the gap region between the horn or pintle and movable wing parts. There have been several interesting studies on the suppression of this rudder cavitation with modified rudder shapes and-or various types of devices attached to the region inside or around the gap. However many of them lack completeness in terms of suppressing the rudder cavitation and do not consider the additional devices to increase the rudder performance. In the present study a newly devised rudder system which has recently been proposed by the authors is analysed with regard to the lift augmentation and cavitation suppression. The new rudder system differs from conventional ones in the cam devices which effectively close the gap between the horn or pintle and movable wing parts. Results from both model tests and numerical simulations using a CFD (computational fluid dynamics) code are presented. Two types of model tests are carried out: one is visualisation of the cavitation and; the other is surface pressure measurement in a cavitation tunnel. For cavitation visualisation the pressure in the cavitation tunnel was decreased artificially to lower the cavitation number. The cavitation phenomenon was then recorded with a video camera and analysedX28976

Marine surveillance is important for environmental protection and sustainable management of the EEZ (Exclusive Economic Zone) of coastal nations. The majority of European coastal nations already have dedicated marine surveillance programs. These are operated by national authorities and are based on a combination of coastal radar airborne and vessel surveillance systems. During recent years several European coastal nations have used satellite monitoring as an integrated part of their surveillance system. Satellite-born SAR (synthetic aperture radar) can provide large-area coverage of the Earth's surface independent of weather and light conditions. SAR has evolved to become one of the most important sensors for operational monitoring of the marine environment. Since 1994 KSAT (Kongsberg Satellite Services) has been delivering SAR-based oil spill and ship detection services to European end users in near real time (ie less than one hour after satellite overpass). The technical capabilities have been documented and accepted and the main challenge now is to obtain long-term sustainable services. KSAT is now engaged in a new approach: the multi-user model in which several users share costs data and information creating a sustainable operational service.

AUVs (autonomous underwater vehicles) operate independently of human control. The more sophisticated types of AUV are able to make their own mission-conformal decisions including appropriate action in unforeseen situations. The latest AUV development from Atlas Electronik is the SeaWolf. This is at present in the advanced development stage. It is a sophisticated type of AUV and will shortly be introduced into the market. The SeaWolf's mission spectrum extends from the inspection of 2D and 3D underwater facilities maritime security in the underwater domain and to applications for maritime science. The vehicle belongs to the lower weight class of AUVs has a large payload capacity and an endurance of several hours with a speed up to 8 kts. It is able to hover and has a very good manoeuvrability due to its 5 propulsors. The SeaWolf can also be equipped with a fiber-optic cable length of up to some kilometres for broadband on-line data transmission. The Seawolf AUV with its unique combination of power and manoeuvrability will be able to execute a comprehensive variety of inspection surveillance and reconnaissance tasks including in high current environments and covering extremely complex structures. In addition the Seawolf is able to detect and classify anomalies without human support. Such anomolies can be thus handled even in areas of extensive marine growth such as mussels and barnacles and in regions of poor visibility.

Symp held in Australia on 13 - 15 oct 1980 Papers are Coal burning bulk carriers for an Australian coastal trade Coal - an alternative fuel Dynamic properties of coal fired propulsion plants Safety aspects of coal fired ships The development of VAP turbine plant Experience from burning heavy fuel oils of varying quality in diesel engines Choosing the correct fuel oil additive to obtain maximum cost savings A modern approach to fuel improvement with chemical additives The pretreatment and cleaning of modern low - grade heavy fuel oils Nirex fresh water distillers recent technical and economic advances ALFA - LAVAL marine plate heat exchangers advantages of the centralized cooling system ALFA - LAVAL plate heat exchangers for marine applications Fuel savings achieved by improved hull condition The use of reliability engineering theory in the design and operation of ships Optimum ship weather routing Looking beyond the 1980s - is hydrogen the transport fuel of the future? Fuel savings - a ship operators experience of the performance of underwater coatings Two-stroke and four-stroke engines in the early eighties - basic requirements and targets for the future Operational economy of B & W 2-stroke crosshead diesel engines Fuel oil economy in the 80s diesel engines economical aspects The design of modern coal fired boiler plant for marine use

In the advent of All Electric Ship (AES) and electric warship in particular several sophisticated and energy demanding electric systems are to be installed aboard including propulsion motors and pulsed loads. The latter require high power for a very short interval and therefore introduce certain severe power quality problems to the ship electric network especially referring to voltage and frequency modulation. In this paper an initial attempt is made to study thoroughly these modulation phenomena caused by pulsed loads. Thus the typical electric network of a warship in the context of the AES is considered focusing mainly on appropriate modeling and studying the consequences of a pulsed load along with the propulsion motors and the generator set. More specifically a generating set of two synchronous generators a large propulsion asynchronous motor the electrical loads of the system through a MV/LV transformer and a pulsed load. The studied pulsed load is a rail gun which uses the stored energy of a large capicitor. All models are developed pulsed load model is fully parametric enabling the analysis of various case studies. Critical factors are investigated while power quality indices for the assessment of voltage or frequency modulation as referred in the relative standards are calculated. Finally general conclusions are drawn regarding the problems that will be emerged at the future integration of electrical pulsed loads into warships the design of their power systems and the energy storage systems in order to ensure operationa91906

Despite the importance of the YC (Yucatan Channel) flow as the sole passage of water from the CS (Caribbean Sea) into the GoM (Gulf of Mexico) the knowledge of the structure and variability of YC's flow was limited in the past due to limited direct measurements in the YC. However recent observations show a considerably more complex flow field than previously thought and suggest that the mean YC transport is smaller than previous estimates. The new observations also allow a more detailed evaluation of model results than previously was possible. As part of the analysis of results from high-resolution numerical simulations of the GoM (Gulf of Mexico) and the CS the structure and variability of the flow across the YC are described and compared with observations. The main model inflow into the GoM is found near the surface in the western part of the YC while return flows back into the CS are found near the surface on the eastern side of the YC and along the eastern and western slopes around 1500 m depth in agreement with recent observations. Variations in the upper inflow and deep outflow transports seem to correlate with variations in the extension of the Loop Current as suggested by previous analyses of observations and models. Such correlations are especially high near the time when Loop Current eddies are shed into the GoM.

Clad steel pipelines consist of a typically 3 mm thick internal corrosion resistant alloy with metallurgical bonding to the outer carbon steel pipe. The method of clad pipe manufacture gives intrinsic rise to disbonded areas (defects) in between the two materials and there is concern that such disbondment defects may trigger local buckling of the cladding when the pipe is subject to severe bending e.g. when installed by the reeling method. The possibilities for local buckling of the cladding material with the steel pipe in pure bending are addressed. Disbonded areas are studied numerically and the critical defect size regarding local buckling of the cladding is established and compared with the allowable defect size as defined in the manufacture specification. In traditional pipeline design the possible strengthening effect from the cladding on a steel pipe is not taken into account. In this paper the strengthening effect from the cladding with the pipe in pure bending is studied. For the pipeline analysed it is shown that the deformation controlled local buckling resistance of the clad steel pipe is at least equivalent to a full thickness carbon steel cross-section. Hence for a clad steel pipeline installed by the reeling method the required wall thickness can be calculated by assuming the total wall thickness to be solid carbon steel.

Since 1993 at least eight large ships have been lost due to hull-girder collapse. Some major classification societies have joined their forces to develop new set of rules for design of oil tankers. The intention is to ensure improvement in the overall safety of the hull structure increase of durability of ships in terms of corrosion margin and fatigue strength and to introduce transparency in formulae for scantling requirements. Results of these efforts are common rules for structural design of oil tankers that are called JTP (Join Tanker Project) rules and which are expected to become effective in April 2006. Perhaps the most important new rule requirement is that for ultimate vertical bending moment capacity of hull-girder which has not been prescribed in older versions of ship classification rules. Here the relative increase in safety of a Suezmax oil tanker resulting from this new rule hull-girder requirement is quantified by means of ship reliability analysis. The probability of structural failure is calculated using a first-order reliability method. The evaluation of the wave-induced load effects that occur during long-term operation of the ship in the seaway is carried out in accordance with IACS recommended procedure. Comparative analysis of long-term distributions of vertical wave bending moment calculated by two independent computer sea-keeping codes is carried out. The still water loads are defined on the basis of a statistical analysis of loading conditions from the loading manual. The ultimate collapseX23533 Structural reliability of marine diesel engine propulsion shafting systems

Hull girder strength is the most fundamental strength of ship structure. Generally ships have been designed to resist all loads expected to arise in their seagoing environment. The objectives in structural design have been to maintain a ship structural integrity for normal operating conditions. A combination of most severe loads is usually selected as the normal design load. However a large number of ship accidents continue to occur despite the advancement in the navigation system. These accidents have caused the loss of cargos pollution of environment loss of human beings. In the design of ships structural strength is generally assessed for the intact condition. In intact condition the critical load case for mono-hull ship is the vertical bending moment which reaches its maximum in head seas. Both horizontal bending moment and torsional load may play insignificant role. The torsion is considered only when there are large opening on ships. This methodology has been successfully applied to ship design for many years. However when a ship is damaged the whole scenario for the safety assessment changes. In damaged condition its floating condition could be changed dramatically. Its draught is increased and it may heel. It could also have large holes in the structure. So the load combination becomes very essential part of structural safety assessment in damaged scenario. Different damage scenarios in two tankers have been studied.

Successfully drilling through depleted sands to reach deeper targets often demands a delicate balancing act between maintaining mechanical stability in normally and over- pressured shales while controlling fluid losses due to hydraulic fracturing. For a porous formation it is generally accepted that hydraulic fracturing pressure is partially dependent upon formation pore pressure. However the models commonly used to predict both fracture initiation and fracture propagation are often unable to predict the changes in hydraulic fracturing pressures due to depletion. Due to the prohibitive cost of a new North Sea well a stability analysis was performed to determine the feasibility of sidetracking from an existing well and then directionally drilling through two highly depleted sand formations with a single hole section. The case study presented compares the original mechanical stability and hydraulic fracturing estimates with the actual mud weights used to successfully complete this difficult drilling operation. Descriptions of hole instability and fluid losses are presented along with the drilling fluid parameters used to combat them. Methods used for estimating formation pore pressure in-situ stresses and formation rock properties are also described. In addition possible explanations for the differences between the planned and actual stability estimates are explored with future recommendations for similar operations. Diagrams graphs and tables appear on pages 7 to 8.

Over recent years there have been some potential threats to the continued health of the GBR (Great Barrier Reef). Several causes have been suggested but a satisfactory scientific basis has not been established. One unresolved question is the effect of river plume runoff on the GBR. There is an associated question about the effect of nutrients which may be carried off the adjacent agriculture and pasture lands during rain. A prototype SLFMR (scanning low-frequency microwave radiometer) has been flown in the vicinity of the mouth of the Herbert River and an associated campaign of in situ CTD profiles and current meter measurements has been carried out to investigate the dynamics of the river plume. Results are presented and these show that there is a net northwards drift of the surface water in the Lagoon close to the mainland which diverts the river water towards the north. Estimates are made of the eddy diffusion coefficient for the mixing of the low-salinity estuary water with seawater in the main Lagoon area. Under these conditions the estuary water remains within a few kilometres of the coast and drifts northwards with the near-shore wind-driven current. It is shown that the present SLFMR with its spatial resolution of about 1 km and salinity resolution of about 1 psu is suitable for mapping salinity gradients in these conditions where there is a fairly high influx of fresh water with high gradients in salinity.

Measuring acoustic backscatter in the water column is a low- cost reliable method for examining the long-term behaviour and distribution of zooplankton populations. The WCP (water column profiler) is introduced. This is a self-contained echo-sounder designed for long-term autonomous operation. It can be used in either downward-looking mode (from a moored surface buoy) or in upward-looking mode (from a submerged mooring). It has selectable parameters for pulse length and sampling interval. The data are recorded in digital form and averaging in both time and range is available. On-board storage of up to 64 Mb of non-volatile Flash RAM allows operation for periods up to six months in length for 150 m water depth sampled at 1 m intervals every minute. Interfacing to a real-time data link is possible for buoy- mounted installations. A WCP operating in British Columbia has produced time series of acoustic backscatter showing the evolution of the behaviour and abundance of the dominant species of zooplankton (Euphausiids and Amphipods). Examples of these data are presented and discussed comparing the results at the two frequencies and the implications for acoustically discriminating size with a multi-frequency instrument.

Knowledge of current and future wave conditions near the shore has become more important due to increasing military requirements involving operations such as beach assault landings and special operations. Thus there is motivation to transition SWAN (simulating waves nearshore) into operational use. SWAN is a wave model that can be run at high resolution in the littoral regions of the ocean and promises to provide output within the practical limits driven by operational constraints. To build confidence in the model results and meet the new demands of preparing SWAN for operational use SWAN testing and evaluation is being undertaken as part of the NGLI (Northern Gulf of Mexico Littoral Initiative). The wave models discussed were set up to support NGLI. Within such a venue model evaluation can be carried out suitability for shallow-water simulation can be demonstrated and an operational wave prediction system can be predicted. Wave model output compared to observations for the period of 27 August to 19 September 2000 is reported. Wave hindcasts using WAM (wave model) and the SWAN model are evaluated. In addition estimated wind speed and direction from the COAMPS (coupled ocean-atmosphere mesoscale prediction system) atmospheric model used for surface wind forcing on the wave models are compared to corresponding NDBC (National Data Buoy Centre) wind measurements. Validating wind and wave data were acquired from two operational and one experimental NDBC buoys deployed for NGLI.

One traffic policy measure is the toll road. In most European states drivers have to pay road tolls. Payment of tolls is now starting to become connected with European traffic policy. The toll is not only the financial instrument for building and supporting highways but is also becoming a measure of traffic policy for dividing and directing traffic from overloaded highways to less overloaded systems such as public transport (railway). The efficiency and economy of road toll systems depends upon the degree of constructed well-equipped road networks their course and road connections as well as the structure of traffic. Several European states that do not have their own toll stations (Austria and Bohemia) have decided to bring in the 'vignette' (an all-in charge toll). This toll is a temporary measure until the automatic toll can be implemented. States that already have toll stations on their road (Italy France and Slovenia) implemented automatic tolls few years ago. In Slovenia users use the automatic ABC system and the contemporary pay road toll with DARS cards. At the same time Slovenia is developing a project ABC system for the third fourth and fifth classes. At the moment many European states are undertaking research with the aim to equalise and simplify the electronic toll system and vehicle classification according to the European standard. This will make the movement of people and goods inside European area much easier. By implementing electronic technology without cash payment Slovenia has caught u93586 Electronic two-stroke targeted at bulkers

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.