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A numerical model is presented to predict the interaction of multidirectional random surface waves with one or more trapezoidal submarine pits. In the present formulation each pit may have a different side slope while the four side slopes at the interior edge of any given pit are assumed equal. The water depth in the fluid region exterior to the pits is taken to be uniform and the solution method for a random wave system involves the superposition of linear-wave diffraction solutions based on a two-dimensional boundary integral equation approach. The incident wave conditions are specified using a discrete form of the Mitsuyasu directional spectrum. The results of the present numerical model have been compared with those of previous theoretical studies for regular and random wave diffraction by single or multiple rectangular pits.

The implications of the Donaldson Report on the salvage industry following the grounding of the Braer are briefly examined. A number of significant areas are raised which will allow the industry to respond to some of the recommendations put forward. The UK Coastguard will take a much more positive role in casualty prevention if all the recommendations are adopted. The recommendations may contain a contradiction. One proposal deems a ship to be in peril if a tug is ordered to assist it. Also the voluntariness of an operation may be removed if a tug is ordered to a ship in trouble under intervention powers. The salvage industry should ensure that the Coastguard and Lloyd's arbitrators understand and protect its position. The Donaldson Report may allow the salvage industry to participate in the training mentioned in recommendation 88. If so the salvage industry should respond.

This unique source of reference on all international measurements and definitions covers such areas as accountancy, agriculture, chemistry, computers, energy, engineering, finance, fishing, food and drink, forestry, health investment, light, optics and photography, mathematics, minerals, metals and alloys, sound and music, pulp, paper and packaging, statistics, space and time, textiles, transport and weapons. Also included are more than 130 tables of conversions and instantly accessible calculations of complicated sums such as annual percentage rates, net present values, percentage reversals, conversions of square inches into square centimetres, barrels of oil into tonnes, and pounds force per square inch into kilograms force per square inch.

Presentation format is used to provide an overview of the environmental impact of shipping with measures for its assessment and control. Copies of slides cover: the impact of human activity population growth expectations and GDP on the marine environment; typical sources of sea and air pollution particularly from oil and chemical tankers; the regulatory work of IMO; the location and extent of serious marine accidents and oil spills; human and mechanical causes of accident; increasing ship safety through effective structural design navigation systems and operations; the E3 tanker; risk assessment and risk reduction techniques; ship environmental accounting; factors influencing the increasing demand for greater marine environmental protection; and the role of environmental criteria in ship design.

The equilibrium FGLR (free-gas: liquid ratio) method is a new method for calculating gas production rates within a material balance model. The method calculates the reservoir FGLR at which there would be no overall movement of the gas-liquid contact. It is then assumed that the reservoir is tending towards such an equilibrium position i.e. the reservoir FGLR converges towards the equilibrium FGLR. Given an estimate of the rate of convergence and a forecast of liquid production (from decline analysis for example) these assumptions are sufficient to give an approximate forecast of a reservoir or well gas production profile. The method can be used to forecast associated gas production from oilfields with significant gas-caps especially thin oil-rims for which wells are usually drilled close to the original gas-oil contact. It gives a gas production forecast broadly comparable to a decline-curve oil production forecast. Unlike the Muskat method it does not depend on unmeasurable reservoir-scale relative permeabilities. The method has been mathematically derived from some basic assumptions about average reservoir behaviour. The validity of the assumptions and the method have been checked by comparison with historical production data from eight oil-rim reservoirs.

This book is the story of the author and he uses all the information he learned from books, tapes, seminars and colleagues in the Financial Services profession. Ian Green doubled his production and still found time to get married, witness the birth of his first son, move house and start his own company. He began his life insurance career in 1996. After 5 months as a tied adviser he became an IFA. He now runs a successful independent practice in London, England working primarily in the owner/ entrepreneur marketplace. Ian regularly appears as a financial expert on television and radio and writes for the financial press. He is sought after speaker at seminars the length and breadth of the UK as well as black-to-black MDRT appearances at meetings in Canada and the USA.

BP and Shell's fast-track approach to the development of Foinaven and Schiehallion is described. These two fields are located in deep water between the Shetland and Faroe Islands where the weather and currents are harsh. The reservoirs are shallow and require multiple drill sites and use of horizontal wells. Foinaven will employ a floating production storage and offloading (FPSO) system based on a rebuilt Russian submarine carrier now known as Petrojarl Foinaven with two subsea well clusters. Annual production will be 85 mbd. The design and operation of the facilities are being undertaken by a consortium led by McDermott Marine Construction and Golar Nor Offshore. Schiehallion will produce 142 mbd using a large FPSO with multiple subsea well clusters. Both developments will use shuttle tankers for oil export. The tendering strategies and technology for both developments are described.

The conditions prevailing in the ullage regions of tankers have been studied and the likelihood of subsequent production of pyrophoric material that could present an ignition hazard has been investigated. The nature of deposits recovered from tanks reaction of hydrated iron oxide with ullage gas sulphidation/oxidation of recovered tank scales behaviour of hydrated iron oxide critical reaction temperature and electron microscopy of iron oxides are examined. Sulphidation of hydrated iron oxide in atmospheres of varying hydrogen sulphide content and oxidation of reactive iron sulphide in atmospheres of controlled oxygen content were evaluated and on-board tests indicating the stage at which ullage composition favours formation of reactive deposit are discussed.

The Global Maritime Distress and Safety System (GMDSS) applies to passenger and cargo ships over 300 TGT on international voyages. However it will affect smaller craft in a number of ways. Onshore facilities must offer GMDSS requirements but additional systems will be voluntary. Any financial cutbacks will therefore hit these systems rather than the GMDSS. It is also likely that some vessels such as fishing boats will be required to have some sort of GMDSS under regulations that cover their industry. Five other methods of transmitting a distress signal are reviewed: Emergency Position Indicating Radio Beacons (EPIRB) Navtex Digital Selective Calling (DSC) Inmarsat and Search and Rescue Radar Transponder (SART). The question of training and certification for small craft using GMDSS is also considered.

The ability of a warship to complete its mission after an attack depends on its susceptibility (ability to avoid being hit) vulnerability (level of damage when hit) and recoverability (ability to recover from a given level of damage). Survivability is the combination of these three elements. The importance of considering all the aspects of survivability at the earliest stage in the design is described as well as then managing it throughout the design process. Methods that can be used to assess survivability and measures that can be taken to reduce vulnerability are discussed. An insight into how recoverability data can be used to optimise competing warship designs is presented along with an example of how susceptibility data can be combined with vulnerability data to provide a comprehensive analysis package.

The importance of alignment for installations with two-stroke diesel engines has been accentuated since vessels become bigger but less stiff engines more powerful and the shafting stiffer. For a typical arrangement of a two-stroke diesel engine installation the engine is directly coupled to the propeller by one or more intermediate shafts and the propeller shaft. Usually these systems have two stern tube bearings and one or more intermediate bearings. Insufficiently loaded bearings may be damaged. To improve reliability it is essential to arrange the bearings of the shafting system in such a way that all bearings are well loaded but the interaction between them is as small as possible. The influence of the shaft arrangement on the main bearings also has to be considered. The load distribution is influenced by the stiffness of the shafting system the weight the initial bearing offset and the draught of the vessel which leads to a static deformation of the ship hull. By rotating the crankshaft the vertical bending stiffness of the crankshaft changes there is a variation of static main bearing load over one revolution. Practical methods to check and validate the alignment in a given installation are web deflection and jack load measurements sometimes also strain gauge measurements.

Saipem were contracted in 1994 to construct two 22 inch diameter 45 km pipelines from the Moroccan coast to the Spanish coast across the Straits of Gibraltar for the transportation of natural gas. Many problems had to be taken into consideration including: extreme water depth severely uneven rocky seabed steep slopes high current velocities opposite flowing currents along the water column prevailing wind and sea states the tourist and fishing seasons and the fact that the area is a busy shipping channel. There was no simple single solution to the problems but combinations were used of solutions such as: increasing the length of the external ramp an accurate pre-engineering survey accurate guided laying on the bottom use of Doppler Log for underwater positioning

The object of this treatise is to investigate finding a procedure through which it might be possible to judge with adequate certainty the minimum amount of the stability that would be sufficient for a certain vessel, both in seagoing vessels and those on inner waters. The sections use the following as judging principles: the initial transverse metacentric height, the main dimensions of a vessel, the stability arm curve and the dynamical lever curve.

HF radar was demonstrated 30 years ago for the mapping of ocean surface currents waves and winds. Within the past four years these systems have achieved operational status. The history of the system's evolution is reviewed together with early impediments the creation of a compact design and the development of supporting software. Ongoing research is investigating the assimilation of current-map data into numerical models with the prospect of accurate near-shore circulation forecasts. Finally improvements are reviewed which are underway including bistatic augmentations compact skywave radar and GPS synchronisation which will allow several radar stations to operate simultaneously on the same frequency.

A robust structural stress method has been developed and validated for fatigue evaluation of ship structures through a major joint industry project. The structural stress method not only provides a consistent method for characterizing stress concentration effects on fatigue in different joint types and loading modes but also offers a rapid estimation procedure for stress intensity factors for arbitrary joint geometries and loading modes in fracture mechanics context. As a result a master S-N curve approach has been recently developed by using the mesh-insensitive structural stress parameter and its direct linkage to fracture mechanics principles. This paper provides the detailed theoretical development application examples and validation results. The applications for the master S-N curve approach are illustrated by using various offshore/marine examples.

A single degree of freedom model is presented to simulate the large amplitude roll motion in beam waves. The effect of excitation modelling on the fitting capability of the nonlinear roll motion equation to experimental data is studied. Several frequency dependent and constant effective wave slope coefficients are derived for five different scale models corresponding to different ship typologies by a parameter identification technique. A common trend for slender bodies is evidenced for excitation parameters. Finally the effects of the coupling roll-pitch in beam waves is analysed starting from experiments in large amplitude waves. It is concluded that a quadratic coupling term is needed in the pitch equation and that the introduction of a coupling term in the roll motion equation does not improve its simulation capability significantly.

Conf held in New York in 1974 Papers are Bigger bigger and bigger Insurance aspects of the million ton tanker Discharging supertankers without hazard to the environment Impact of 1973 IMCO on supertanker pollution prevention The million ton tanker crude oil terminal Offshore tanker terminals - study in depth Strength problems/design loads in VLCC construction Measurement of gaseous oxygen concentrations aboard ship New dimensions in supership construction and trade routes A step toward increased profitability - the heavy duty gas turbine powered ULCC Million ton tanker fleets LNG container systems Slow speed diesels for larger tankers The other side of the coin - a look at the LOOP project The development of a hull surveillance system The million ton tanker - unique design considerations Manoeuvring characteristics of large tankers LNG carriers marine gas turbine plant Peak shaving in marine transportation Wide shallow VLCCs Seagoing barge train Progress in computerised structural analysis of large vessels Steam propulsion for super carriers

A linearized analysis of the motions of a very large floating mat-like structure for use as an airport is presented. Small amplitude incident waves and small resulting deformations are assumed. Hydrodynamic aspects are analyzed using an extension of Frank's method. Structural aspects are assessed using orthotropic plate theory. The consequences of these motions based on typical airport dimensions and varying structural characteristics are presented. Deformations of the structure seemed to be diffraction driven for both steel and concrete regimes. Most significant motions were at the forward end of the structure. Motions diminish from the port end inwards and also along the length of the mat.

The MULTISPAN research project was established to provide criteria and guidance on design methods for unevenness induced free spans subjected to VIV (vortex induced vibrations) from steady currents. An overview of the DNV Design Guideline developed within the MULTISPAN project is given with requirements for structural modelling free span analysis current measurements data analysis and acceptance criteria for free spanning pipelines against steady current induced VIV. The premises for the technical development of the limit states probabilistic modelling applied reliability study performed and the performance of the selected design formats compared to current industry practice are discussed. The important link between hydrodynamic response models safety factors and design criteria are discussed.

The L21-31 is a new smaller-medium-speed engine from MAN B&W Diesel. Its output is between the L16-24 and the L27-38 engines (the latter were introduced to the market during the late 90s). The L21-31 engine is available for marine applications (propulsion GenSet and diesel-electric) and for power plant applications. It has a bore diameter of 210 mm and a stroke of 310 mm and is available for 900 rpm (60 Hz) and 1000 rpm (50 Hz) with cylinder outputs of 190 - 215 kW. As the latest engine of the new generation the L21-31 engine uses the proven design concept of the L16-24 and L27-38 engines and an array of adapted components which meet the specific requirements of GenSet and propulsion service in that output range. Today's product development processes have to comply with a complexity of requirements like precise product tender specifications based on understanding of market demands use of superior materials tools and technologies optimal product supply chain management of relations with suppliers