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Contents Cyril King, 'The Death of a Shipyard - The Birth of Dart Marina' p.5 Steve Hucklesby, 'Henry Dinham Chard - Shipbuilder, Lyme Regis, 1759-1847' p.23 David Eeles, 'The Development of Torquay Harbour to the Thirties' p.29 Ron Howell, 'To Sail No More, The Story of Lord Napier' p.83 Colin Green, 'Forest Ports of the Severn' p.87 Robert G Alwood, 'Sailcloth (Coker Cloth)' p.112 The Navy Board, 'Manufacturing Cloth for His Majesties Navy' p.129 Joe Varley, 'Dermot Keogh, Master Mariner - Life and Times of a Dubliner' p.137 Kevin A Doughty, 'His Majesty's Ships Badger and Sandfly - The Occupation of Iles St Marcouf, 1795-1802' p.149 Peter Lacey, 'Norman Court, China Express' p.167 Dr Michael Bender, 'British Yachting Narratives 1604-2005, Part 2 Additions, Corrections and References' p.178 Maldwin Drummond, 'A Brief History of Yachting and its Development over the last 200 years' p.201 Sadru Bhanji, 'Barbary Pirates and the West Country' p.218 David Jenkins, 'West Country Steamship Owners, Some Suggestions for Further Research' p.231 Philip Gloyn, 'Who Were the Trinity House Pilots Operating on the River Exe in the 19th Century?' p.244 Index of Previous Journals and Maritime Monographs p.264

A receiver implementation is proposed that uses robust techniques on top of direct sequence code division to eliminate multiple access interference in an underwater acoustic environment. Computation of error probabilities and Asymptotic Relative Efficiencies with respect to other single user or multi-user detectors for various channels and contaminated heavy tailed noise distributions show that the proposed detectors maintain a nearly optimum performance regardless of the degree of noise contamination. It is also confirmed that the detector structure is insignificantly influenced by unspecified variations in noise densities. Moreover the theory of the proposed techniques can be easily extended to multi-channel processing to provide space diversity. A simple two-stage multi-user detector is introduced which works for both coherent and non-coherent network communication and can be applied to synchronous or asynchronous CDMA. In all cases the received signal is sampled and forms a test statistic which combines the good qualities of ordering of samples and partitioning of the observation space: robustness increased efficiency and ease of implementation. The decorrelating multi-user detector and its implementation for M-orthogonal signaling are provided. The GQT (generalised quantile test) is modified to operate for multi-user reception. The operation of the M-ary decoder is described. A two-level competitive neural network uses the GQT to identify the user's spreading sequence and the transmitted symbol from an M-ary orthogonal signaling alphabet. Asymptotic performance is obtained and numerically evaluated. Gold signaX45220 Multi-user undersea acoustic communications in the presence of multipath propagation

The Poseidon Project is a joint venture between Statoil Total and IFP (Institute Petrole du Francais) with the main objective of developing cost effective multiphase boosting and transportation technology. The industrial version (Poseidon 301 a co-axial rotordynamic multiphase pump) was installed on the Gullfaks A platform in 1994 and has accumulated around 5000 running hours. The booster has been found to increase the daily production rate by more than 2000 cu. m. of oil. The SMUBS (Shell multiphase underwater booster station)concept is a joint R&D programme involving SIPM (Shell Internationale Petroleum Mij) Norske Shell and Framo Engineering targeting surface subsea and downhole applications. The main features are: all active components that are susceptible to wear are located in a single retrievable cartridge for simple installation and maintenance; the pump cartridge unit has no orientation requirements; the seals can be set and tested hydraulically; and installation and retrieval is carried out vertically by one tool with one ROV (remotely operated vehicle) for monitoring only. The objective was to boost production from the Rogn South subsea well 10km from the Draugen platform. Shell companies and Statoil are now co-operating in the development of a subsea electrical driven multiphase booster system (ELMSUBS) for applications down to a water depth of 400m. Studies are also underway to evaluate requirements for extending the range of operations to water depths in excess of 1000m.91453 Multiphase drag reduction in horizontal flows

US Navy ships produce several liquid waste streams that must be treated prior to overboard discharge or stored for shore-side disposal. A major source of overboard discharge is oily wastewater (bilgewater) which collects in most machinery spaces and is generated in volumes too large for long-term storage. Bilgewater is a highly variable mixture of potable water and seawater with contaminants from a number of sources. The types and amounts of bilgewater contaminants vary widely. The development and procurement of an effective economical system that provides secondary treatment of shipboard oily wastewater to meet emerging environmental requirements is described. The need for secondary treatment was identified on newer 'dry bilge' ships which produce smaller volumes of bilge water that contain high concentrations of emulsified oil. The UF (ultra-filtration) membrane system development produced performance specifications incorporating OSA (open systems architecture) to procure these membrane systems. The process and progress in procuring an effective affordable oily wastewater secondary treatment system are described.

An underwater vehicle has already been developed. It is hoped that this vehicle will be used to inspect offshore and-or coastal underwater structures. The vehicle must have high manoeuvrability in water currents and-or waves. A prototype underwater vehicle has already been developed for this purpose using two-pairs of mechanical pectoral fin devices that show high manoeuvrability in water currents and-or waves. In order to put this vehicle into practical use the desired levels of guidance and control law for the underwater vehicle must be determined efficiently. Therefore a project was begun to develop a CFD-based motion simulator for the underwater vehicle. However this motion simulator cannot consider the effect of free surface including waves and the water currents. Therefore it is intended to apply this simulator to the prediction of the motion of the underwater vehicle in the water currents and-or waves. This study was carried out as basic research for adding the effect of free surface including waves to this numerical motion simulator. Firstly experimental observation was carried out to understand the behaviour of the submerged body near free surface and waves. A rectangular column was considered as a submerged body. Secondly the motion of the submerged body was computed by newly developed a numerical motion simulator which is based on the above CFD-based method. Thirdly the numerical accuracy was also examined qualitatively by co88341

One of the biggest challenges in the offshore industry is the prediction of the VIV (vortex-induced vibration) response of deepwater risers and free spanning flow lines. Due to the presence of high currents vortex shedding occurs at high frequencies. This excites high structural modes resulting in high fatigue rates. The most common remedy is the use of VIV suppression devices such as helical strakes. Typically more than 50 per cent of the riser is covered with recent riser installations employing up to 100 per cent. It is therefore important to be able to model strake behaviour successfully. The challenge faced by most designers is predicting the correct VIV response. Numerous experimental and numerical studies have been carried out in an effort to improve the understanding and prediction of cylinder VIV behaviour. The numerical simulation is presented of rigid circular sections both bare and fitted with strakes using a second order accurate finite element CFD (computational fluid dynamics) method. Two turbulence models are examined: the Spalart-Allmaras RANS (Reynolds Averaged Navier Stokes) and the DES (detached eddy simulation). Pragmatic high Reynolds number simulations of fixed and moving cylinders are presented and compared with laboratory experiments. Flow visualisation provides insights on how strakes mitigate VIV. Comparisons between RANS and DES results are also presented and discussed.

Impact pressure due to sloshing is of great concern for the ship owners designers and builders of the LNG carriers with regard to the safety of LNG containment systems and hull structures. Sloshing of LNG in a partially filled tank has been an active area of research with numerous experimental and numerical investigations over the past decade. In order to accurately predict the sloshing impact load it is necessary to develop advanced numerical simulation tools which can provide accurate resolution of local flow phenomena including wave breaking jet formation gas entrapping and liquid-gas interactions. A new numerical method is presented which has been developed for the simulation of violent sloshing flow inside a 3D LNG tank considering wave breaking and liquid-gas interaction. The sloshing flow inside a membrane-type LNG tank is simulated numerically using the FANS (Finite-Analytic Navier-Stokes) method. The governing equations for two-phase air and water flows are formulated in curvilinear co-ordinate system and discretised using the finite analytic method on a non-staggered grid. Simulations were carried out for an LNG tank in transverse and longitudinal motions including horizontal vertical and rotational motions. The predicted impact pressures were compared with the corresponding experimental data. The validation results clearly illustrate the capability of the present two-phase FANS method for accurate prediction of impact pressure in sloshing LNG tank including violent free surface motion 3D instability and air trapping effects.

Sea Surface Salinity directly affects the status of coastal ecosystems and serves as a tracer for seawater constituents associated with freshwater runoff. SLFMR (the scanning low-frequency microwave radiometer) was used in various coastal locations to evaluate its performance for mapping sea surface salinity and to show its application to studies of coastal plumes and buoyant jets. In a sequence of three campaigns the radiometer was flown repeatedly over the Cheseapeake and Mobile Bay plumes and over the northern Gulf of Mexico and Florida Bay using a twin-engine Piper Navajo aircraft. Extensive surveys of sea surface salinity distributions were carried out on time scales of a few hours. The instrument was field calibrated using in situ data from oceanographic research vessels and the resulting salinity maps were corrected for known environmental influences. The logistical convenience and broad dynamic range of the instrument allowed surface maps to be generated quickly over waters that were either significantly fresher or more saline than standard seawater. The instrument performance and resulting map quality were thus found to meet the requirements of coastal oceanographic studies that are characterised by large buoyancy signals and a variety of forcing effects that evolve relatively rapidly in time and space. The instrument and data processing system are first described and two new methods of field calibration method are presented. Examples of surface salinity maps of rapidly evolving coastal plume features are then presented and interpreted using supporting in situ data. Finally t102865 Observing system evaluation Peter R Oke ; Magdalena A Balmaseda ; Mounir Benkiran et al.

The aquatic chemistry fundamentals of ocean carbonate chemistry are considered. Some of the main questions considered when studying the global carbon cycle are the exchange of CO2 between the ocean and the atmosphere and the internal redistribution of carbon species within the ocean due to uptake and remineralisation of organic matter and calcium carbonate. All of these processes involve various species of the ocean DIC (dissolved inorganic carbon) system thus the fundamental aquatic chemistry aspects of these equilibrium reactions of the carbonate system need to be understood. The six chemical species that need to be solved to completely define the ocean carbonate system are identified. The concentrations of the individual carbonate species can be determined using algebraic graphic or computer programming approaches. Each of these is briefly reviewed. After this the broad patterns of the distributions of the measured properties versus depth and between oceans are summarised. The distributions of carbonate system parameters within the ocean are primarily controlled by photosynthesis and respiration and calcium carbonate precipitation and dissolution. A brief summary of how the different measured variables vary with the different processes is presented. Next is discussed what actually controls the pH of seawater. After this the carbonate system calculations are considered and it is shown how the measured properties can be used to calculate the concentrations of the individual carbonate species. The burning of fossil fuels making concrete and cuttingX23615 Ocean catamaran seakeeping design based on the experiences of USNS Hayes

Oil waste that enters the ocean comes from many sources: accidental spills or leaks natural disasters or as a result of chronic and careless habits in the use of oil and oil products. The ocean environment makes the emergency response more difficult and complicated especially in bad weather. Management of such an event involves and organised contribution covering all procedures of disaster operation from monitoring and detection to mitigation and relief. This paper presents methods of SAR image and GIS technology applications for oil spill management in coastal areas. The developed framework is based on automatic detection and mapping of oil spills in SAR image and precision of oil spill location and extent maps which includes information about the spill thicknesses and geographic references such as major towns and features along the coastal area. The output from SAR image processing is then transferred into an oil spill trajectory simulation model to simulate the next destinations of the oil spill. Oil spill trajectory predicts the movement spread and coastal impact of oil spill in the marine environment. The output vectors from trajectory simulation used as input data for creating other disaster products include oil spill risk map affected area map and emergency response map. Each product demonstrates the results from various analyses aspects and includes situational analysis risk analysis damage analysis and emergency response analysis using satellite SAR image in GIS and image analysis software. All the models and applications are described and shown.

The performance of variable volume exhaust rebreathers is characterised by an EVR (exhaust volume ratio) and XO2 (supply gas oxygen concentrations). The development of the approach used to enhance the performance of these systems is detailed. An analytical model has recently been developed for predicting the circuit oxygen levels in variable volume exhaust semi-closed underwater breathing apparatus at various mission depths and diver activity levels. Unmanned testing in June 2000 with a commercially available system showed good agreement with this analytical model over a wide range of diver depths orientations and activity levels. The analytical model showed that for given operational parameters of maximum and minimum depth there must be an optimum EVR and XO2 which will maximise capability while ensuring allowable maximum and minimum partial PO2 (pressures of oxygen) in the breathing circuit. By specifying boundary conditions on the analytical model at maximum and minimum depth for the associated allowable minimum and maximum PO2 an analytical relationship for EVR and XO2 was developed and subsequently validated in unmanned testing. Associated EVR and XO2 are presented for three missions of possible interest to the Navy; shallow depth deep depth and a switch over to closed circuit at very shallow depth.

The Soft Yoke Mooring and Offloading system (SYMO) has been developed to allow the tandem mooring of an LNG carrier to the stern of an LNG FPSO or a Floating Storage & Regasification Unit in harsh environments. The SYMO system consists of two mooring legs supported by a crane. A yoke structure is suspended at the bottom of the two mooring legs by uni-joints. The tip of the yoke is connected to the bow of the LNG carrier via roll pitch and yaw articulations. When connected the yoke structure is horizontal. Upon disconnection the yoke settles at an equilibrium position characterized by a pitch angle of 35° to 40° with respect to the horizontal. This paper focuses on the disconnection phase where a challenging problem arises. After some introductory information the SYMO system is presented with the challenging problem during disconnection described and a possible fully passive solution outlined at a conceptual level. Numerical simulations with kinematics software have been performed to prove the potential of the proposed concept. These simulations are outlined. Further confidence in the validity of the concept is gained experimentally by model tests at a large scale of 1:16. The scope and main results of these tests are presented. Finally a few model tests are selected as a basis to perform numerical simulations using a fully coupled CFD-kinematics code. Numerical and experimental results are then compared to assess the feasibility of using such an advanced tool for engineering applications. Conclusions are drawn.

The book is designed to assist sea-going personnel in their understanding of the safe operation, testing and maintenance of ships electrical equipment and services. It describes electrical equipment employed in international shipping. A ship's electrical power system is explained in terms of its main and emergency generation plant and the distribution network. Electrical safety is stressed throughout. The types and significance of circuit faults are examined together with the various forms of protection methods and switchgear operation. An appreciation of generator construction and its control is followed by a guide to its protection and maintenance. A wide range of ancillary electrical services for ships lighting, catering, refrigeration, air conditioning, laundry equipment and cathodic protection are described together with battery support, care and maintenance. The book also reviews the special design and maintenance of electrical equipment used in potentially hazardous areas, in relation to oil, gas and chemical tankers. Sections are as follows: the electric propulsion scheme, the power supply network, review of motor operation, controlled rectification and inversion, converter types, propulsion system operation, harmonics, propulsion auxiliaries and protection, high voltage on ships, high voltage safety equipment and high voltage equipment testing. There are also 'question' and 'answer' sections throughout.

PEMS (predictive emissions monitoring systems) are used to monitor the emissions of operating plant without continual measurement of the emissions. When using a PEMS readily measured parameters are fed into a computer program which accurately predicts emissions. The analytical ability of such a program could be used to inform an engine control system. This project interfaces a real time computer model for NOx emissions with operating engines. The core computer model has been developed. This is a thermodynamic model that can predict NOx emissions from an operating engine in real time on a standard PC. The model uses chemical kinetics and a unique method for calculating the rate of dilution of the burnt gases by unburnt air during NOx formation in the combustion chamber. The chemical kinetics scheme for NOx includes the extended Zeldovich mechanism and a set of reactions involving nitrous oxide. The addition of nitrous oxide reactions to the extended Zeldovich mechanism increases predicted NOx by up to 15%. Conversion of fuel nitrogen to NOx is not included in the model but a brief analysis of the governing chemical kinetics is made. The kinetics model runs within a zero-dimensional thermodynamic model for the combustion process. The model is calibrated to a particular engine by simultaneously measuring in detail engine data and NOx emissions. The matching process is automated. Once calibrated the model will predict NOx emissions when supplied with a limited set of data which are normally available from an operational engine.93671

There is evidence of changes in sea level and wave height on various time-scales globally and regionally. Various recent studies have tried to understand and quantify changes in sea level storm surge and wave climatology due to present and predicted climate change. For example the North Atlantic Oscillation appears to be correlated with increasing wave height in the North Atlantic over recent decades. These changes may or may not be anthropogenic but must be planned for in an integrated coastal management plan. The impact of any increase in wave height in the North Atlantic at the coastline in the North Sea the Irish Sea the Malin-Hebrides Shelf and the English Channel will be quite different. The effect of increasing sea levels due to global warming and any changes in tides and surge height and frequency is combined with changes in offshore wave height. The effects of change in wave period and direction may also be significant. Shallow water wave modelling using the WAM and SWAN wave models provides a useful tool for examining the possible impacts of climate change at the coast. This is part of a project studying the vulnerability of the UK coast to changing wave climate and sea level. Initial results validating the wave models and testing simplified NAO scenarios are presented.

For deepwater development in the Gulf of Mexico SCRs (steel catenary risers) supported from both SPAR and semi-submersible platforms have proved to be successful solutions for in-field flowlines tie-backs and export systems. It is envisaged that this will continue to be a promising solution in ultra deepwater applications up to and beyond 10000 ft. The study commissioned by the MMS (Mineral Management Service) investigated the reliability of large-diameter SCRs in ultra-deepwater operations. The primary damage mode considered is fatigue failure. A probabilistic methodology for fatigue reliability is developed which uses deterministic cumulative fatigue damage indicators namely the stress levels and cycles associated with the various sea states and the fatigue strength of the members. Uncertainties in structural load and material properties are accounted for by assigning probability distributions and standard deviations to the deterministic stress levels. Furthermore fatigue strength parameters Miner's indices and capacities are modelled as random variables. FORM (first order reliability method) is used to estimate fatigue reliability. The methodology is applied to three deterministic case studies presented by Intec Engineering. The case studies involved either a SPAR or a semi-submersible platform. For the sake of brevity a case study involving only a SPAR platform is presented in this paper. The effect of uncertainties in parameters on fatigue reliabilities is investigated. It is observed that the fatigue reliability estimates followed siX40633

Fourth Int Symp held in Houston 25 - 28 April 1979 Papers are The US merchant marine - future in forecast Elastic foundation of deckhouses Minimum freeboard requirement for dry foredecks - a design procedure Capsize safety Cavitation erosion prevention by air injection An overview of current and proposed tank vessel safety and pollution measures A statistical and economic evaluation of stern tube bearing and seal failures The effect of hull proportions on IMCO tanker segregated ballast requirements A gas turbine electric propulsion system for an LNG carrier A preliminary assessment of the demand for reception facilities stemming from the implementation of MARPOL 1973 Future development of the slow speed diesel engine Naval ship design - past present and future Training of ship operators - the marriage of theoretical and practical education Improving the fuel efficiency of navy 8300 (1200 psi) steam plants An at - sea comparative analysis of deck performance with and without automated information displays A comparative analysis of naval auxiliary and merchant ship design Simulator training for improved shiphandling skills Low friction propulsion by means of boundary layer control Paravene roll stabilisation The United States nuclear merchant ship programme - financial protection issues in the operations of nuclear merchant ships The estimation of ship motion induced forces A practical guide for determining the vibration characteristics of plate structures

In bistatic scattering geometries the detection of a signal scattered in the forward direction by a stationary object can be difficult because the incident and scattered waves combine into a simultaneous mixture. Reverberation can complicate the measurements even further. At opposite ends of the forward scattering phenomenon are the Rayleigh scattering region where the scattered wave is masked by the incident wave; and the geometrical optics region where the two wavefields interfere to form an acoustic shadow. Pressure sensors can only provide an estimate of the magnitude of the intensity associated with an equivalent plane wave field while true intensity sensors measure simultaneously the acoustic pressure and particle velocity components (or a related quantity such as acceleration displacement or pressure gradient) at a single 'point' in space. The coherent measurement of both acoustic field parameters provides not only the magnitude of acoustic intensity but also the phase between acoustic pressure and velocity. It is supposed that processing methods could be developed which exploit the relationship between these types of coherent measurements in order to extract information regarding the presence and nature of an object residing on or very close to the bistatic baseline. The hypothesis is explored computationally using a rigid prolate spheroid as a canonical scattering body. First the underlying concepts of acoustic intensity are considered. Then the computation of the field scattered from a rigid prolate spheroid is examined to introduce the forward scattering effect and generation of the acoustic shadow. LastX41752 Processing of three dimension vertical cable data over SEG/EAGE physical model

MBC-1000M is one of the powerful supercomputers that are available today. LUCKY and LUCK_C are programs created to work on multi-processor systems. These programs have algorithms created especially for these computers and use MPI service for exchanges between processors. LUCKY resolves shielding tasks by the multi-group discreet ordinate method and LUCKY resolves critical tasks by the same method. Only XYZ orthogonal geometry is available. With little space steps to approximate discreet operator this geometry may be used as universal one to describe complex geometrical structures. Cross-section libraries are use u to Pm approximation by Legendre polynomials for nuclear data in GIT format. The programming language is FORTRAN-90. In the absence of vector processors (that can obtain a time profit of up to 30 times) sufficient value for efficiency of parallel calculations is obtained using 'space' (LUCKY) and 'space & energy' (LUCKY_C) paralleling. The AUTOCAD program is used to control geometry after a treatment of input data. Programs have a powerful geometry module. Output results may be treated by PC graphic programs.

The next generation of general-purpose frigates are likely to suffer from reduced budget priorities compared to those of land and air forces with the predominant land campaigns presently occupying NATO and other forces. They will also be required to deliver greater flexibility of use with changing and volatile threats. The frigate solutions will be highly cost constrained and in shrinking fleets expected to deliver higher levels of capability than currently provided. The balance of weight space and cost allocated to the propulsion system will be under intense scrutiny as resources are sought to maximise the combat system capability and flexibility of use. This paper compares the eight and space impact of current generation mechanical hybrid and full electric propulsion systems choices on a typical general-purpose frigate. Currently mechanical propulsion solutions are the least demanding in terms of weight and space at the whole ship level. Mechanical-electrical hybrids like CODLAG propulsion and integrated full electric system solutions available today bring other advantages but impact the combat systems 'payload' in space and weight terms in a frigate-sized vessel (taken to be around 6000t). A non-integrated hybrid system is more space demanding than the other solutions.