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Conf held in Paris Sept 3 - 5 1979 Papers are Some observations on linear hydroelasticity of ships Slamming and whipping of ships among rough seas Wave induced vibrations of a ship hull with internal damping A comparison of theoretical and measured symmetric responses of a segmented model in regular waves Vertical response of flexible ships in waves A study of the wave induced ship/hull vibration - springing caused by higher order wave exciting force Wave induced antisymmetric response of flexible ship Numerical analyses by digital computer programme rosas on responses of ship/ hull structure at sea Stochastic prediction of whipping vibration of very high speed ship due to slamming Mechanically induced excitation and rsponse (propeller and other machinery) A method for predicting effects of propeller hull configurations on vibratory excitation of ships Propeller induced ship hull vibration - design stage calculation with sufficient accuracy at a reasonable cost Vibration analysis of large ships including higher mode vibration Prediction of super structure vibrations in tankers Vibratory behaviour of containerships - correlation between measurements and calculations Summary of a design procedure for minimising propeller induced vibration in ships Vibration analysis of the Norwegian coast guard vesel Hull girder flexural vertical vibration caused by second order unbalanced moment of diesel main engine

A theoretical method for plate tearing by a rigid wedge is developed in this paper. The studied model is an idealization of ship-grounding and collision damage. The analysis model postulates that the plate curls up into two curved surfaces behind the wedge tip and that the plate material ahead of the wedge is tensioned and ruptured due to the direct pushing. Based on a parametric study, a semi-empirical formula is proposed for determining grounding force in the event of a ship running onto rocks in a high-energy grounding. The bottom strengths of single hull structures and double hull structures in ship-grounding incidents are compared. Finally, simple formulae for determining damage resistance and the extent of damage in ship grounding, expressed in terms of the ship principal particulars, are developed.

Ship design is a multi-disciplinary and multifaceted activity which converts the information that characterises the needs and requirements of the ship into knowledge about the ship. Optimisation methods have been an integral part of ship design largely because effective design synthesis can be performed on the basis of simultaneous consideration of all the design requirements. Ship design has been based traditionally on a sequential and iterative approach. With the availability of efficient and effective optimisation methods in recent years several researchers have attempted to solve ship design problems using optimisation methods that allowed them to deliver designs while considering multi-disciplinary interactions within a short time span. However most of these approaches using optimisation fail to identify designs that are robust i.e. those less sensitive to variations caused due to fluctuations in freight rates cargo discharge rates fuel oil prices etc.

The motion of a ship through water is made possible by a highly complex combination of factors affecting speed, efficiency and performance. Of these factors, the temperature of the water surrounding the ship may hold the greatest impact on performance parameters. Through three in-depth papers, the author explores the direct impact a variety of variable conditions have on the efficiency and performance of a ship. He arrives at his conclusions through detailed statistical analyses of such as factors as exhaust temperature, water temperature, in-service time, wave action and marine fouling on a ship's body.

The advent of HTS (high temperature super-conductors) has provided impetus for developing rotating synchronous machines for both marine and industrial markets. Since 1991 AMSC (American Superconductor) has been developing super-conducting machines. In modern ships propulsion systems are so large and heavy that in many applications they force the rest of the ship to be constructed around them. HTS propulsion motors provide relief from this constraint because compared to conventional motors HTS motors are more compact lighter weight more efficient quieter (lower in acoustic and structure-borne noise) and lower cost (acquisition as well as operational costs). HTS motors look very attractive for large-size low-speed propulsion applications. AMSC is currently factory testing a 5 MW 230-RPM ship propulsion motor for ONR (the Office of Naval Research). This is a prototype for an ONR 36.5 MW ship propulsion motor that will also be designed and built by AMSC for delivery in 2006. HTS motor technology is maturing rapidly and both Naval and marine ship drive applications will greatly benefit from these advances. The status of ship propulsion motor development is presented as well as its unique characteristics for ship propulsion.

The book contains the results from a programme of systematic model experiments planned by the authors that were carried out at the Swedish State Shipbuilding Experimental Tank. The purpose of these was to study the influence of main dimensions and centre of buoyancy on the resistance and propulsive qualities of model ships being tested. 9 ship models were designed, constructed and tested. The influence of variations in their length-breadth ratio, breadth-draught ratio and the longitudinal position of the centre of buoyancy were studied. The experimental results were converted to the scale of a ship having a displacement of 9750 tons and a trail speed of 16 - 16.5 knots. The results are also expressed in dimensionless form in order to facilitate their application to similar ships of different size.

The Guide is an effective compendium of the findings of a broad and intensive research programme by the 'Ship Structure Committee' since the end of the Second World War. Its purpose is to promote sounder ship structures. The first section presents the fundamentals of mechanics of materials and of ship strength. The remaining sections include numerous examples of objectionable engineering practice in ship structures and suggests remedies and improvements. Chapters comprise of: Stresses and strains on ships, Minor and major openings in ship steel structures and welding joints and welding sequence.

The two volumes provide aspects of both ship theory and practice, from ship design to the integrated design process. The first volume (chapters 1 to 9) covers hydrostatics and strength and introduces the tools used by the naval architect, mathematical techniques, instruments and the computer. It also reviews the special hazards to which a ship is subject and the means of dealing with them. Other topics include structural design, safety factors, criteria of failure and the final chapter deals with the environment in which the ship must operate and the internal environment within which the crew must function.

Ship STEP (Standard for the Exchange of Product Model Data) which is composed of AP 215 (Ship Arrangement) AP 216 (Ship Hull Form) has been developed more than last 10 years and it is now at the stage just before IS (International Standard). It is expected the ship STEP world be used for the seamless data exchange among various CAD/CAM/CAE systems of shipbuilding process. In this paper the huge and copmplicated data structure of ship STEP is briefly reviewed at the level of ARM (Apllication Reference Model) and some abstract test cases which will be included as part of the standards are introduced. Basically ship STEP has common data model to be used without losing compatibility among those three different ship AP's and it is defined as the modelling framework. typical cases of data exchange during the shipbuilding process such as hull form data exchange between design office and model basin midship structure data between shipbuilding yard and classification society are reviewed and STEP physical data are generated using commercial geometric modeling kernel. Test cases of ship arrangement at initial design stage and hydrodynamic data of crude oil carrier are also included.

The purpose of this study is to determine the sensitivity of ship acquisition cost and fuel consumption to specific fuel-cell generator design-parameters. The ASSET ship simulation design program provides a comprehensive evaluation of ship machinery and cost. Evaluation of calculated ship benefits at various levels of fuel cell system performance show which parameters have the most influence on overall ship design and cost. The results quantify the potential for improvement in ship design due to specific levels of performance improvement in the fuel cell generators and provide guidance for future fuel cell generator Science and Technology and acquisition programs. The results show SSFC (ship service fuel cell) generators provide cost-competitive performance compared to existing SSGT (ship service gas turbine) generators. A lifecycle cost study is recommended as the next step in the process. A follow up study is planned for a Sensitivity Study of fuel cell performance characteristics for a Hybrid Propulsion application for the IPS Notional Surface Combatant.

This Code is based on the experience of people directly involved in shipping and ship management. It derives from intensive discussion and co-operative effort within experienced ship management companies, assisted by representatives of leading classification societies.

The evolution of the merchant shipping fleet over the past 30 years is reviewed. The emerging trends in ship structural design are highlighted emphasising that a rational life-cycle design should be reliability-based and include maintenance and operational considerations. Bureau Veritas' integrated approach to life-cycle ship design VeriSTAR is presented. Foreseeable changes in ship design philosophy are considered in terms of developing more rationally based Rules.

Sea state may have a significant effect on the manoeuvering properties of a ship at the entrance to ports. Additionally ship motions induced by a sea state may cause grounding. Accurate prediction of vessel response in a seaway is important to ensure safe ship operation. Currently a study is being undertaken to improve the prediction of ship response in a seaway on the Ship-Handling Simulator at the AMC (Australian Maritime College). One of the challenges is how to simplify and solve the equations of motion whilst adequately representing the complicated non-linear coupling motion in six-degrees of freedom. It is intended to develop formulae to predict the forces and moments exerted on a ship by a seaway using simple input parameters to describe the sea state and ship. Captive model tests have been carried out with 'Marad F' series bulk carrier models to measure wave-induced forces and moments for a number of wave headings. The experiments were carried out in the AMC's Towing Tank and Model Test Basin. Froude-Krylov calculations have been used as a first step to predict the incident wave forces and moments. These predictions have been compared with the model test results. The predictions show a similar trend to the model experiment results and promising agreement was found within a defined wavelength regime. The first step of the research for describing the sea state effect using the Froude-Krylov approach is presented. Experimental results are given. Future work is idenX30143 Development of a simulator for plate bending by line- heating T Nomoto ; K Aoyama

The formulation of a mathematical model representing the true behaviour of a ship in extreme weather conditions is the most important task in developing a methodology for evaluating ship capsizing and developing a new rational stability criteria. The theoretical background and mathematical formulations representing ship dynamics in large and steep waves are presented. The equations of ship motions in oblique waves include the hydrodynamic forces imposed on the hull at large heel angles by steep waves and the forces caused by water on the deck and deck-in-water that may occur in extreme waves. These phenomena are discussed in detail and their mathematical models are presented. They include the modelling of water shipping on and off the weather deck the dynamic effects of water trapped on deck with the volume changing during motions and the effects of deep immersion of the deck. These together with the modelling of course keeping make the theoretical model complete i.e. all the important forces acting on a ship in large and steep waves are represented. The theoretical models of the individual phenomena have been validated by specially designed physical model experiments. The equations of ship motions are solved in time domain and the simulation program has been validated against model-scale experiments of ship capsizing in extreme waves. Examples of the numerical simulations and comparisons with the corresponding model tests are presented.

This book is written in Russian Cyrillic. It is about dynamic analysis or calculations of ship structures, and includes topics such as the theory and methods of calculation, dynamic calculation systems, dynamic calculation in ship design, hull strength (particularly against forces such as ice and waves), inertia and ship rolling, displacement and dynamic loads.

This book covers the stability, trim, construction, tonnage and freeboard of ships, with ship calculations, for the use of ships' officers, superintendents, engineers, draughtsmen and others. Chapters include those on displacement and deadweight, moments, buoyancy, stresses and strains, structure, stability, rolling, ballasting, loading (homogenous cargoes), shifting cargoes and deck cargoes, flooding, sailing and propulsion, trim, tonnage, freeboard (the loadline) and useful tables of calculations and rules.

A brief history of the Jebsens Ship Management Group is given. Its mission statement is that it is an industrial dry bulk shipping group providing quality and value-added transportation and management services. Quality assurance is achieved through a Total Quality Management programme. It is a member of the International Ship Managers' Association (ISMA) and meets the standards of their code.

The equations of motions of a ship traveling at a constant speed in regular oblique waves are formulated and solved in the time-domain. The newly developed 3D time-domain ship motion calculation method is applied to predict the wave forces and ship motions for a Wigley ship-hull in head waves and a catamaran ferry in oblique sea.