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One of the main purposes of a LHD (landing helicopter dock) ship is the transportation and transfer of a large number of troops and their associated equipment from sea to shore. Sea transfers are carried out using landing craft which are embarked and disembarked from a flooded well dock area located at the after end of the ship. The behaviour of landing craft within the flooded well dock is of critical importance to the operators of an LHD ship. The turbulent flow at the dock entrance and wave motions inside the well dock may cause a landing craft to impact. It is therefore necessary to develop a modelling capability that can assess landing craft designs and determine the operational limits of these designs. To date the relative motion between the parent ship and the landing craft has only been assessed experimentally. Numerical investigations have focused on determining the wave profiles within the well docks. The next step is to include landing craft and to determine the relative motion of the landing craft and the parent ship. The preliminary results are presented of a feasibility study into landing craft motions inside a flooded well dock using commercial FE (finite element) analysis software. This FE code has fluid-structure interaction capabilities through its use of SPH (smoothed particle hydrodynamics) techniques. The study suggests that the relative motion between the LHD and the landing craft could be determined and therefoX40131 Modelling of multiphase pigging operations H Yeung ; J Montgomery ; P C R Lima

International Conference held on 2 3 4 May 1979 Greenwich Papers are The North Sea - A Challenge of Disorganised Opportunities North Sea Planning - The role of National Regimes Preconditions for an Int Offshore regime - administration management policing and emergency services A German view of North Sea Mineral Development Solving the problems at sea is not only a question of regime The North Sea and its approaches - the case for and against an Int Regime a German view The Geological evolution of the North Sea Weather and waves in the North Sea North Sea Oceanography - the current nd situation and possible future developments Sea Use Planning in the Southern North Sea - The shipping background The Importance of North Sea Fishery Resources Oil Pollution The North Sea - hydro graphic knowledge Offshore Policies and Policy Making in the United Kingdom Dutch Offshore Policy Danish Regime in the North Sea Danish Offshore Policy The Defence of the North Sea and Approaches to North West Europe Prevention and Control of Pollution and Protection of the Marine Environment - actions undertaken by the European Community The Oil Industry Int Exploration and Production Forum Study Group - Energy environmental aspects technology fisheries shipping surveillance enforcement and defence alternative legal regimes

The reform of the CFP (Common Fisheries Policy) has been in the air for several years and now some decisions at least have to be taken. The EC (European Commission) held preliminary hearings across the Community including the UK as early as 1998 and issued a Green Paper on the future of the CFP outlining its approach to reform in March 2001. This was widely debated until the end of September 2001. Now proposals for reform are close to being finalised and are likely to be tabled by March 2002 at the latest. Then the real debate will begin. The stakes in this debate are very high. As the EC said in the Green Paper 'the Common Fisheries Policy has not delivered sustainable exploitation of fisheries resources and will need to be changed if it is to do so.' It was also said that 'the catching sector in particular will have to become significantly smaller than it is today in order to be sustainable and the Community needs to plan for major structural adjustment'. There is a sense of urgency to reform given the poor state of some of the major fish stocks such as cod and hake. First the achievements of the CFP in its first 20 years are considered. After this seven key issues for reform are examined as seen from the EC's perspective.

The VIVACE (vortex-induced vibration aquatic clean energy) Converter is a new concept to generate clean and renewable energy from fluid flows such as those abundant in oceans rivers or other water resources. The underlying concepts for the design scaling and operation of VIVACE were introduced in a previous paper. In its simplest form a VIVACE modulo consists of a single rigid cylinder mounted on elastic supports and connected to a PTO (power take off) system. The cylinder is placed in a steady unidirectional current and excited in VIV. The VIVACE modulo was tested in a low turbulence free surface water channel to demonstrate the concept generate electricity measure its efficiency and calculate basic benchmarking measures such as energy density. Tests carried out were tailored to the particulars of the VIVACE modulo which dictate that the cylinder operate in VIV under high damping and as high a Reynolds number as possible. At the same time a broad range of synchronisation is required to make VIVACE effective in energy generation in a realistic environment. Due to these requirements VIV tests have not been carried out before in the subspace applicable to the operation of the VIVACE modulo.

The use of unmanned marine vehicles has greatly increased in recent years. Unmaned surface boats with electric propulsion must possess power management capabilities in order to minimise the risk of propulsion power loss while the vessel is performing a certain task. The investigation of the electric propulsion system prior to its integration onboard an unmanned boat is the subject of this work. It includes a theoretical part which focuses on the analysis and performance assessment of the propulsion motor; however the assessment is not complete until both motor and propulsion devices are tested experimentally in a specifically built facility. In this sense a method for the analysis of permanent-magnet dc motors is given in conjunction with the development of a testbed for thrust and torque curve acquisition of power trains including motor and waterjet. Speed and load control of the propulsion system is achieved through pulse width modulation which appears a promising and simple technique for efficient control of dc propulsion systems. Finally the control system implementation is visited because it is considered an essential component of both the power management and propulsion systems of any unmanned boat.

Intact stability an ability not to capsize without damage of enclosed buoyant space is one of the most fundamental requirements for ship design and operation. This paper summarises the activities of JASNAOE's (the Japan Society of Naval Architects and Ocean Engineers) strategic research committee on estimation methods of capsizing risk for the IMO new generation stability criteria (SCAPE) in 2005-2008. This committee consists of 18 experts from three universities two research institutes and one shipyard in Japan. For facilitating the development of the IMO new generation intact stability criteria methodologies of predicting parametric rolling broaching and stability under dead ship condition were investigated at the SCAPE committee. For parametric rolling free-running model experiments for a post-Panamax containership and a car carrier in irregular head waves are reported and difficulty of predicting the maximum roll angle in numerical simulations is remarked. Parametric roll in beam waves is also investigated experimentally. For broaching the probabilistic methodology of calculating probability of broaching is presented using deterministic thresholds. For stability under dead ship condition a piece-wise linear approach is applied to annual capsizing probability prediction with sea state statistics. FORM (the first order reliability method) is also applied to this problem. These outcomes were reported at theX43504

The 2D viscous unsteady and incompressible flow by a circular cylinder in oscillatory motion is investigated by solving the Navier-Stokes equations. A CFD (computational fluid dynamics) code based on a multi-block FDM/FVM hybrid method is developed and extensively tested against other CFD and flow-visualisation results. The multi-block hybrid method uses rectangular-grid-structured FDM (finite difference method) at far field and body-fitted-coordinate- structured FVM (finite volume method) in the near field. The FVM code is able to reproduce with high accuracy the flow characteristics around arbitrary 2D bodies for various experimental conditions. The FDM code used in the outer domain is developed so that it can include arbitrary rigid and free-surface boundaries. The numerical computations successfully capture many important flow features for various types of flow conditions. In particular the flow simulations for an oscillating cylinder are able to reproduce through advanced computer graphics software various interesting features observed in the physical experiments for a variety of K-C numbers. The developed computer program is proved to be robust and efficient to be able to simulate more complicated flow problems including both seabed and free surface.

Research has shown that naturally occurring light outdoors and underwater is partially linearly polarised. The polarised components can be combined to form an image that describes the polarisation of the light in the scene. This image is known as the DOLP (degree of linear polarisation) image or partial polarisation image. These naturally occurring polarisation signatures can provide a diver or a UUV (unmanned underwater vehicle) with more information to detect classify and identify threats such as obstacles and-or mines in the shallow water environment. The SHRIMP (shallow water real-time imaging polarimeter) is presented. This sensor can measure underwater partial polarisation imagery and is a passive three-channel device that simultaneously measures the three components of the Stokes vector needed to determine the partial linear polarisation of the scene. SHRIMP was developed in 2000 to provide a new tool for the diver working in this adverse environment. It has completed its testing phase that included both laboratory and field-testing. Some of the analysis that has begun on images obtained during the field-testing of this sensor is discussed. The SHRIMP sensor system is overviewed. The phenomenology that led to the system design is discussed and an overview of the system is presented. The field-testing is explained along with some of the data analysis results. Finally the conclusions that can be drawn from these results are discussed.

NOAA CINMS (the National Oceanic and Atmospheric Administration Channel Islands National Marine Sanctuary) California is involved in a process to site marine ecological reserves within its boundary. In order to address all aspects of this often-contentious issue the sanctuary along with the California Department of Fish and Game developed a joint stakeholder-driven process to weigh up the impacts of an ecological reserve. A marine reserve working group was formed spring 1999 whose goal is to consider the benefits of creating a marine reserve within CINMS and if deemed beneficial to determine the optimal location or locations. In addition the group was charged with using consensus-derived criteria and the best available science and socioeconomic information to support its decision. As well as the working group a science panel and a socio-economic team were formed to support the working group by providing information on the biological and economic impacts of marine reserves. A GIS (geographic information system) was chosen as an ideal tool to support the working group in making a group-based decision because of the help it would provide in visualising the complex socioeconomic and ecological data available.

The heat left over from the formation of the planet combined with that generated by radioactive decay drives the internal engine of the Earth. This heat is the cause of elevated temperatures in mines and is the ultimate source of energy for volcanoes hot springs mountain building and earthquakes. The heat flux is the product of the temperature gradient and the thermal conductivity. Scientists use temperatures measured in boreholes coupled with conductivity measurements on the rocks penetrated to derive the heat flux through the continents. At sea they use the temperature gradient measured by thin probes driven into the soft sediments of the ocean floor multiplied by the thermal conductivity of these sediments. A personal retrospective of the attempt to explain Bullard's Law covering early heat flow surveys the sedimentary observations magnetic measurements and physical interference's that led to the realisation that fluid flowing through the oceanic crust must be responsible for the variability. The original discovery of a hydrothermal plume predicted by the physical model of a layer of high permeability at the top of the igneous crust is discussed. Finally the advances that have come from separate considerations of advective flow and conductive thermal flow of heat through the ocean floor are considered.

Research into current interactions within an array of buoyancy cans top-tensioned risers (WHB risers array configuration) is presented. This research includes an extensive test campaign in a large-scale current channel and is aimed at providing understanding of both the quasi-static behaviour (mean inclination due to drag forces and mask effects) and the fluid-structure dynamical interactions (VIV (vortex induced vibrations) and WIV (wake-induced vibrations)). Preliminary numerical analyses are carried out with DeepLines (FEM) and DeepFlow (CFD) software in order to validate specific modeling principles and similitude rules suitable for these particular model tests. The risers array model focuses attention on the buoyancy cans motion to check clearance issues. Three main parameters are tentatively reproduced at model scale: the riser deflection under drag forces; the reduced velocity governing the occurrence of VIV; and the reduced damping governing the dynamic response amplitude. The risers array is tested under various current incidence and for a wide range of current (and reduced) velocities. Mask effects are quantified and equivalent drag coefficients for each riser of the array are identified as a function of the current incidence.

This eighth edition was edited by the Society for Water Treatment and Examination. The council of the Society set up a special committee for the purpose and that committee in turn enrolled a number of specialists to revise the various chapters. Although water treatment has occupied a considerable proportion of the space in previous editions, the original title did not mention treatment and it was felt that this, together with a complete resetting of the book in a different format, was sufficient justification to change the title to the present one. There was so much new material to be included in this edition that in order to keep the book within reasonable size limits, a large part of the historical and similar matter which appeared in previous editions has had to be omitted. The use of milligrams per litre in place of parts per million introduced in the last edition has been maintained, nut there is now a much bigger change: all units used are SI (metric) units, in conformity with the Report of the Working Party on Metric Units with reference to water, sewage, and related subjects.

13rd International Marine Systems Design Conf held Pittsburgh 8-10 June 1988 Papers are The subcavitating/supercavitating hybrid propeller An advanced method for design of optimal ducted propellers behind bodies of revolution Optimal hull forms for fishing vessels A knowledge-based system architecture for control of underwater vehicles Roll reduction by rudder control An integrated rig management system for a semisubmersible floating production vessel Computer aided navigation system (CANSY-II) Evaluation of impact loads associated with flare slamming Surface effect ship loads; lessons learnt and their implications for other advanced marine vehicles Advanced ship structural design and maintenance Methods of incorporating design for production considerations into concept design investigations Achieving customer and marketing orientation in marine transport system design Incorporating a seakeeping capability in a computer aided preliminary design system Hull form design - only a matter of the computer ? The components of the propulsive efficiency of ships in relation to the design procedure Design conception and CAE/CAD of hull form Direct curve and surface manipulation for hull form design Intelligent computer aid in marine design and ocean engineering Ship synthesis model morphology Teaching design for students of marine technology Operational aspects in ship design; the case of the roll on/roll off vessel The productive experience of 3D CAD/CAM techniques applied to ship design and construction A new concept for neat fit ship propulsion

Marginal fields must have every economic factor working in their favour to justify any development. This typically requires the operating companies to accept a higher risk standard for the field development decision. If a major company has numerous development opportunities then there is little incentive to develop a marginal field. However operators that are opportunity limited are more willing to accept the calculated development risks of a marginal field. Any development needs to closely examine every cost aspect. Marginal field profitability is frequently controlled more by the commercial arrangements than by technology issues. Examples include: transportation tariffs host facility processing tariffs chemical costs and well intervention services. Close attention to the commercial arrangements and continued technology progress to find more reliable less costly ways of operating marginal deepwater fields will provide field development opportunities well into the future. A process is presented developed by DeepStar to identify technology that has good economic impact on ultra-deepwater marginal reservoirs. This is accomplished with a life-cycle economic analysis which incorporates the new technology and compares the analysis results to a benchmarked field development cost estimate based upon current technologies. The 12 Operators within DeepStar selected 3 representative small tie-back type reservoirs from West Africa and the Gulf Of Mexico and established conventional technology development scenarios for eachX44045

A knowledge-based software package that allows a "quick look" assessment of the economics and risk profile of small oilfields in the Central and Northern North Sea has been developed. The system employs a cost database and cost adjustment algorithms that were calibrated using data from the Thelma Gryphon Fife and Eider Fields as well as cash flow analysis and simulation procedures. It can integrate and analyse the impact of reservoir and production characteristics costs and economic factors on the development decision thereby allowing the most efficient production system to be selected. The economics of the development can be continually assessed as additional data become available making the system a useful management tool. Three production system configurations can be considered: an unmanned wellhead platform tied back to a third- party platform for fluid processing and export a floating production storage and offloading (FPSO) system exporting oil to a shuttle tanker and gas via a tie-in to an existing pipeline and a group of subsea wells tied back to a third-party platform for fluid processing and export.

There is currently a strong market demand for competitively priced large and fast ferries. One of the major considerations in the structural design of larger fast vessels is construction weight savings. The use of high tensile steels aluminium alloys and composites would be an effective means of meeting this requirement. Presently many fast ferries are constructed of aluminium alloys mainly due to the weight savings possible good corrosion resistance and good producibility. In order to reduce structural weight and fabrications costs shipyards have used large extruded sections and prefabricated panels. Although the use of these extruded sections and prefabricated panels has reduced weld distortions and fabrication cost such use is somewhat less effective in reducing structural weight. A new concept for the design and construction of weight-critical vessels such as large fast ferries is presented. A hypothetical fast catamaran ferry of 80 m length is designed as a case study. The design of a vessel focuses on the use of aluminium sandwich panels for some or all of the main hull structural strength members. The local strength of aluminium honeycomb sandwich panels under axial compression bending and crushing loads is studied both theoretically and experimentally. The advantages and disadvantages of sandwich panel designs in terms of the strength to weight ratio and fabrication costs are discussed. A comparison of the aluminium sandwich panel concept with the conventional single skin stiffened panel design approach for hull de100605

The common rail fuel injection system for marine diesel engines can meet the demands for simultaneous reduction of exhaust emissions and fuel consumption. The key techniques of common rail fuel injection system have to be studied in detail. Virtual prototyping is becoming a common practice due to time and cost constrains in diesel engine field industry. The key techniques of common rail fuel injection system for marine diesel engine by use of simulation and test research are presented. The common rail system comprises a low-pressure part composed of fuel tank with pre-filter the supply pump fuel filter and low pressure fuel lines as well as a high pressure part consisting of high-pressure pump with PRV (pressure regulator valve) common rail injectors and ECU and sensors to control these components. Based on the theory of 1D compressible fluid flow dynamics and 2D multi-parts body dynamics a simulation model was established by HYDSIM software. The model with consideration of the effect of leakage from plunger couples and needle couples and the body's elastic deformation etc can calculate the pressure in the hydraulic volumes and the lines the lift of needle and control piston the injection volumes

NAVOCEANO (the Naval Oceanographic office) runs WAM (wave model) and STWAVE (steady-state spectral wave mode) in many areas throughout the world. Nearly 60 different areas need to be run two times a day and around 90 graphical products are produced and displayed on the Web. To help operational modellers set up and maintain the model-run stream a web-based GUI has been devised. The prototype GUI is described together with the lessons learned from that experience. Recent improvements in WAM-run stream allow such a GUI to be created in a logical manner. First these recent improvements are reviewed and it is shown how they allow easier interface with a GUI. The GUI itself uses a number of free packages including the Linux operating system the Apache web server the MySQL database server and the Generic Mapping Tools. The GUI contains a number of distinct tables corresponding to distinct model objects. Examples of objects include WAM models WAM graphics and WAM output spectra. Each object has a distinct set of associated widgets associated constraints and associated routines used to construct the model object.

This book presents a comprehensive review of the current state of adaptive analysis in engineering computation. In chapter 1 adaptive analysis methods such as h, p and hp-versions are described in detail for the finite and boundary element methods. Chapter 2 deals with adaptive finite element techniques for three-dimensional Navier-Stokes equations and other transient problems. In Chapter 3, adaptivity through mesh movements is considered rather than the usual localised mesh refinement techniques. Application to aeronautical problems such as inviscid flow around an aerofoil are presented to demonstrate the versatility of the proposed method. Chapter 4 deals with adaptive finite element method for transient compressible flow problems. The application of adaptive finite element method for phase change problems is described in Chapter 5. In chapter 6, adaptive solution strategies for nonlinear finite element analysis are presented. Particular attention has been paid to computationally intensive operations such as updating the stiffness matrices, decomposition, bisection and line search algorithms. Parallel computation and solution procedures for linear elliptic partial differential systems are presented in Chapter 7, using the finite element method based on automatically unstructured grids. Finally, the application of boundary and finite element methods to three-dimensional problems of acoustic scattering is presented in Chapter 8.

Over the past 10 years there has been a tremendous increase in research and development of UWA (underwater acoustic) communication systems. The desired high data rates are in contrast to the transmission conditions induced by the underwater acoustic telemetry channel which is band-limited and reverberant thus posing many obstacles to reliable high-speed digital communications. Therefore combating time-varying multi-path induced by the transmission channel - especially the horizontal shallow water acoustic channel - is considered the most challenging task. A completely unsupervised receiver concept based on non-data-aided timing recovery blind multi-channel equalisation and carrier phase recovery is proposed. The core of the receiver is an adaptive super-exponential algorithm for multi-channel fractionally spaced blind equalisation. In the noise-free case over-sampling the received signal in space or time leads to a rank-deficient covariance matrix of the corresponding vector process. This seems to be the major obstacle towards a multi-channel adaptive super-exponential algorithm. In the absence of additive noise the optimal multi-channel equaliser setting can also be found as the solution to a suitably chosen quadratic cost function. In the presence of a moderate amount of noise minimisation of the same cost function should result in an equaliser setting close to the optimal one. The optimisation however can now be carried out recursively using a stabilised RLS algorithm. Experimental results with underwater acoustic communication data show good performance of the suggesControl No