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The application of intact stability WC (weather criterion) to ships with large values of both KG-T and B-T like the new large passenger cruise ships requires more stringent rules than those which currently exist. The WC has thus been critically analysed to identify on a historical basis the possible weak points and inconsistencies with modern development of dynamical ship stability and ship design. The possible developments and their impact on ship design are discussed with reference to the design of modern large passenger cruise ships.

This is a code of practice for the construction, machinery, equipment, stability, operation and examination of motor vessels, of up to 24 metres load line length, in commercial use and which do not carry cargo or more than 12 passengers. Chapters cover application and interpretation, construction and structural strength, weathertight integrity, water freeing arrangements, machinery, electrical arrangements, steering gear, bilge pumping, intact stability, freeboard and freeboard marking, life-saving appliances, fire safety, fire appliances, radio equipment, navigation lights, shapes and sound signals, navigational equipment, miscellaneous equipment, anchors and cables, accommodation, protection of personnel, medical stores, tenders (dinghies), sailing vessel features, manning, compliance, vessels operating under race rules and clean seas.

The Code has been developed for application to small vessels of up to 24 metres in length which are in commercial use for sport or pleasure and which do not carry cargo or more than 12 passengers. Chapters cover application and interpretation, construction and structural strength, weathertight integrity, water freeing arrangements, machinery, electrical installation, steering gear, bilge pumping, stability, freeboard, life-saving appliances, fire safety, fire appliances, radio equipment, navigation lights, shapes and sound signals, navigational equipment, miscellaneous equipment, anchors and cables, accommodation, protection of personnel, medical stores, tenders (dinghies), manning, compliance, clean seas and vessels operating under race rules.

An attempt is made to give a general view of the safety in the ship system design process the roles of the yard class owner system supplier and passengers. First a look is taken at the stakeholders in passenger ship safety followed by who will pay for safety and the issue of "foolproof ships". Next system design for safety is addressed covering naval architectural tasks ship systems design for safety and larger passenger ships. After this rules are considered covering prescriptive regulations versus development of technology and some difficulties experienced at the yard. Lastly a case dealing with blackout at sea is looked at and commented on.

There has been significant research on the design of steel structures used in the marine industry. The use of aluminium instead of steel has made it possible to produce lighter and faster vessels. Design rules for aluminium structures however have often been established by changing the material parameters in design codes for steel structures. This approach sometimes gives far from optimal design and in other cases the requirements are non-conservative. One area of concern in developing new design codes is the ultimate strength of the hull plating. During the process of welding zones with reduced yield strength and residual stresses are created. The aim here is to find the ultimate strength of the plate. The collapse strength of rectangular aluminium plates under uniaxial and biaxial compressive stress is addressed. Both non-welded and welded plates with residual stresses and soft zones are considered. Numerical simulations are carried out using the non-linear finite element program ABAQUS. The plates are loaded longitudinally transversally and biaxially until final collapse strength has been reached. Several different aluminium alloys and welded conditions are investigated. The results are compared with existing design codes and recommendations for improvements of current approaches are given.

Wave run-up is one of the main physical processes which are taken into account in the design of the crest level of sloping coastal structures. The crest level design of these structures is mainly based on physical scale model results. However prototype measurements have shown that small-scale models may underestimate wave run-up for rubble mound structures. Therefore wave run-up is studied comparing measurements from prototype and physical models. The main objectives are to improve existing wave run-up monitoring devices; to verify physical scale model data with prototype wave run-up data; and to provide improved design rules for the crest level of sloping coastal structures. The main conclusions of the comparison between the prototype measurements and the 2D physical model tests at both structures are presented.

The objective of a 12-metre designer is to design an object that can be moved around an America's Cup course so that it will cross the finishing line before its opponent using only propulsion forces provided by wind waves and oceanic currents while conforming to the International Twelve Metre Rule the racing committee's rules the Americas Cup Deed of Gift and Lloyd's requirements for Twelve Metre International Rating Class Yachts. While this appears to be rather a strained definition it is meant to point out that a 12-metre yacht is not a powerboat with sails and without an engine. The wide range of engineering methods used during the design and development of 12-metre yachts is described and it is clarified how data resulting from the use of these tools can contribute to better performance. The strengths and weaknesses of each tool are identified and it is shown that next to hard engineering numbers an artist's touch and experience are still required for designing an outstanding 12-metre yacht.

Class NK rules require that the part of the boiler drum where feed water is introduced be provided with sleeves so that an extreme thermal stress may not occur due to direct contact of cold feed water with the drum. A study is presented for estimating the stress condition of the auxiliary boiler drum around the feed water inlet to find out the probability of direct connection of the feed water inlet pipe with the boiler drum. An analysis for obtaining stress distribution is carried out and the area of maximum stress is located. The study concludes that the direct connection of the feed water inlet pipe with the boiler drum may be possible for a boiler of design steam pressure of less than about 2.0 Mpa.

Nauticus Hull is a ship modelling and analysis package produced by Det Norske Veritas (DNV). It has been designed to improve knowledge transfer both within DNV and between DNV and its customers. It is also aimed at reducing the delivery time for a new ship while maintaining or improving safety. The package employs a concept modelling approach which is described in detail. Concept modelling is a way of describing a structure as an assembly of ship structure elements. It offers significant advantages over most current analysis systems in terms of efficiency and quality control. The implementation of the package in the classification concept is described and particular attention is given to its cost-reducing capabilities with regard to direct calculations. A complete Nauticus system is planned for the future which will be integrated with CAD/CAM and planned maintenance systems.

An Integrated Fatigue Analysis procedure for tankers has been developed by Germanisher Lloyd it is based on an overall finite element model of the type used for global strength and vibration analysis and enables the effects of a range of interacting loading conditions on vessel life to be assessed. Methodology described includes the stress analysis of tanker structures (including the hull girder and secondary structural members) and the scheme for Integrated Fatigue Analysis with detailed design (examples illustrate its application to structures in a double hull tanker): the use of the resultant data in the reliable life prediction of vessel structures the optimisation of design and the compilation and verification of rules and guidelines is discussed.

Some of the twin screw ship experience gained by Lloyd's Register's Technical Investigation Department in the context of their problem solving and research activities is described with numerous practical examples cited to show lessons learnt. First a look is taken at propulsion machinery. Next propulsion hydrodynamics and some of its problems are considered. This is followed by an outline of structural considerations. After this vibration and noise are each discussed in turn. Experience with the solution of vibration and noise problems is also used to support the development of Lloyd's Register's new Provisional Rules for Passenger and Crew Accommodation Comfort. Lastly condition monitoring is looked at with Lloyd's Register's primary interest being to use the techniques to enhance survey procedures so that the necessary levels of safety are gained in the most cost effective way to ship operators.

In this paper the vertical bending moments at the midship section of an FPSO are investigated using state of the art numerical simulation tools in combination with experiments. For the seakeeping tests the extremely high New Year Wave (registered in the North Sea) is generated in the wave tank and motions and structural forces are analyzed at model scale. For validation the results are evaluated deterministically and compared to numerical simulations. The time domain calculation allows to artificially change local wave characteristics. The steepness of the selected rogue wave is varied and the influence on wave induced loads is studied. Lastly a comparison with standard procedures of seakeeping analysis and classification rules is given.

Currently recovering from the decrease in Danube traffic caused by the Serbian war the river fleet of the Romanian operators is facing a new challenge. The new European regulations covering the manoeuvring capabilities for inland waterways vessels as well as the new rules for pollution prevention and noise reduction requires drastic measures to be taken by the ship owners. For the moment the most efficient way to solve the problem is to modernise the existing river pushers by replacing and-or upgrading the propulsion and steering systems. From an engineering point of view the most important task of this project was to evaluate and optimise the manoeuvring characteristics to comply with the requirements. This was solved by combined methods of hydrodynamics finite element method and hydraulic systems calculation. These methods are presented. They were used to investigate and optimise the manoeuvring and steering capabilities of a 30 m river pusher 2x1600 HP.

Sessions 2 - 9. These are Prevention of accidents - manoeuvring simulation and crew training Damage stability rules in relation to ship design Fire protection and life saving at sea Collision and grounding mechanics Oil spill prevention with new ship types Reduced exhaust emission with new engine types and new exhaust gas cleaning systems Noise and vibration control International safety management

This paper describes the design of the floater and the mooring system for a small wind turbine. The engineering basis and the hydrodynamics calculations are described as well as the installation and commissioning sequences. The paper deals with the possibility of having a floating mooring designed so that above the water it appears and acts like a single pole permanent pile. If a permanent piling can be avoided in favour of a floating design the wind turbine could be towed to a boat slip of protective shelter for servicing or when there are severe seas following the same rules of safe practice in protecting small boats and yachts. This paper is concerned with the design basis for a one kilowatt floater.

Electric propulsion has tended to be used where conventional methods of propulsion could not be modified to provide the necessary operational requirements. The design of the power system thruster and propeller selection and thruster and propeller drive selection are considered. Both AC and DC drives are available. Also covered is the electrical distribution system's security reliability and flexibility of operation. The choice of propulsion and power plant is often far from straightforward. Details of the design control systems and electrical systems of 2 such vessels the Iolair and Seagair are given. Because of the introduction of such vessels BP (the operators) have introduced a a set of High Voltage Safety Rules. Future trends in the design of such vessels are noted including the increasing use of superconducting motors for propulsion.

Dynamic positioning (DP) is defined as holding a vessel in position automatically without using physical constraints. This was achieved by using thrustors and was particularly important for N. Sea operations where four-point mooring systems were not applicable. The requirements of modern diving support vessels (DSVs) are outlined and the basic parts of a modern microprocessor controlled DP system are illustrated. The limitations and hazards of DP are discussed as is the achievable accuracy of positioning. The possibility of drift-off and drive-off of divers and bells is outlined. The risk of such an occurrence can be calculated and details are given. Operating rules for DP have been devised by Det Norske Veritas and Lloyds Register. The use of improved reference sensors in the future is discussed and this includes using NAVSAT as a back up aid. Microprocessors will find increasing niches and the importance of training is emphasized.

-A basic AUV (autonomous underwater vehicle) control system such as ACE (an IFREMER control system) is associated with a high-level command part. This high level part is provided with complementary features needed by the initial AUV subsystem namely a language allowing plans modification during their execution and a diagnosis and analysis system. The latter checks continuously the information provided by the sensors in relation to some predefined rules in order to ensure the good working of the AUV within its environment. A brief overview of missions programming languages is given. The language PILOT and its control system suggested for the high level command part are presented. This makes it possible to modify plans during their execution. The control system of PILOT is modular and comprises a basic inference engine. Various solutions for AUV missions' safety and supervision are examined. Finally conclusions are drawn.

The application of modern advanced electronic technology to monitoring and control of ship engines and other mechanical equipment has necessitated new rules from the classification societies to cover the requirements of Unattended Machinery Spaces. The extent of control systems varies from the small and simple logic systems to more complex integrated systems and to the very extensive comprehensive systems the facilities offered by each are described and examples given. Basic equipment necessary for the systems is also described and includes central processor unit display units and the attendant computer languages and programming techniques machinery condition monitoring equipment is also discussed although as yet it is not so widely used. The effect of these electronic systems on the job of the marine engineer is considered throughout.

Conf organized by ICE and held in Glasgow 17-18 October 1990 Papers are Insurance and risk control Risk assessment of offshore fish-farming cages Controls and legal provisions governing offshore fish farm developments Classification society rules for fish farms The interaction between physical and biological processes in coastal and offshore fish farming; an overview Computerised mathematical modelling in the assessment of fish farming sites Some considerations in the structural engineering of sea cages for aquaculture Model testing of a cage system for the offshore environment Model tests with flexible circular floats for fish farming The development of an offshore fish cage Some numerical models for predicting wave conditions around aquaculture sites Current forces on cage net deflection Offshore fish farming platforms; development design construction and operation - the SEACON and SULAN Mariculture; biological and management problems and possible engineering solutions Norwegian research and industrial development of floating structures for salmon fish farming Hydrodynamic and biological factors in the design of sea cages for fish culture