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The way stability works is the same for small or large vessels, whether fishing or trading. The book explains what stability is, why ships need it, and how to ensure that they have it. It is a handbook for operators of small vessels and a simple guide for those studying for certificates of competence for large vessels. Chapter 1 is an introduction, looking at seaworthiness and factors affecting stability and water-tightness. Chapters follow on: Buoyancy and floatation and load lines and draft marks, Weights, moments and list, Heel and the metacentre, Free surface and ballasting, Instability and equilibrium, Stability curves, Trim and motion, Damaged stability and bilging, Certificates and IMO recommendations.

OTEC (ocean thermal energy conversion) is a system that converts heat energy into electricity using the temperature difference between surface seawater and deep seawater. A dynamic model construction is described for the transient performance of OTEC plant using the recently developed power cycle in which binary mixtures of ammonia and water were used as the working fluid. The mathematical models were constructed based on thermodynamics and structural features of the power cycle. Confidence in the model's accuracy has been established by comparison of the simulation results with those obtained experimentally in a pilot OTEC plant.

A study is presented of the extreme response statistics of a TLP (tension leg platform) subjected to random seas. Two different approaches are compared: a numerical integration method based on saddle point integration and the Monte Carlo method. While the saddle point method is a mathematically attractive technique which gives numerically very accurate results at low computational costs at any response level the advantage of the Monte Carlo method is its simplicity and versatility. It is demonstrated that the commonly assumed obstacle against using the Monte Carlo method for estimating extreme responses (excessive CPU time) can be circumvented bringing the computation time down to affordable levels. The agreement between the two approaches is shown to be remarkably good.

The contribution of non-linear tidal phenomena to the formation and long-term variability of climatically significant fields of the Euro Arctic seas is considered. The characteristics of residual tidal phenomena are obtained by numerical simulation: residual tidal level achieves significant values in several regions of Euro Arctic seas. Maps of residual tidal currents were constructed: intensive residual currents are observed in the White Sea Pechora Sea regions near Svalbard Spitsbergen bank Bear and Hope Islands. The possibility of adjunction of long-period tides by energy of main diurnal and semidiurnal tides is reported; amplitudes of non-linear long-period tidal waves were evaluated. The impact of non-linear components of motion and continuity equations on formation of different oceanographic phenomena was determined by means of numerical experiments. It was found that convective non-linearity noticeably contributes to the formation of climatically significant non-linear tidal phenomena (residual tidal level and currents and low-frequency tidal waves). Regarding the White Sea example it was suggested that tidal phenomena plays an important role in the formation of the thermohaline structure of tidal seawaters.

Nonlinear tidal phenomena are the result of the energy transfer from main tidal waves to low-frequency and high-frequency spectral range. The contribution of non-linear tidal phenomena to the formation and long-term variability of climatically significant fields in the Euro Arctic seas is considered. Characteristics of residual tidal phenomena are received by numerical simulations. Maps of residual tidal currents were constructed and intensive residual currents are observed. The possibility of the adjunction of long-period tides by energy of main diurnal and semidiurnal tides is reported and amplitudes of non-linear long-period tidal waves were evaluated. The impact of non-linear components of motion and continuity equations on the formation of different oceanographic phenomena is determined by numerical experiments.

CBT is a modern way of training that increases retention by up to 50% or more and reduces training time to almost half compared to traditional classroom training. The Simulation Programmes for Computer Based Training Frigate 124 installed at the German Navy Technical School (Marinetechnikschule Kiel) since July 2001 are covering the operation and maintenance procedures for special systems of the Frigate. The Simulation Programmes lead the students through a series of training sessions. After some background information a look is taken at this approach from the concept to the simulation. This is followed by a brief comment on the experience of this system and its good result.

There is a need to question how much tools for exploration of the oceans are biasing what is seen. Recognising that there may be animals scared away behaviours not seen and adaptations not understood resulting from the lack of a "fish-eye" perspective the Deepscope missions funded by NOAA's Office of Ocean Exploration in 2004 2005 and 2007 were designed to explore with new technological eyes and to focus those eyes on how animals perceive their environments. After some introductory information the stealth camera is considered followed by colour transparency and seeing the light (i.e. defining how the sea realm is viewed from the standpoint of its inhabitants rather than by the distorted view provided by high-resolution light-insensitive cameras and bright white floodlights as understanding how the deep ocean is viewed by its inhabitants provides new tools for exploration and new insights into deep-ocean ecology).

The author considers the advantages of steel construction for all types of ships and boats. The repair, rebuilding and design features which are unique to steel are described. The characteristics of steels and alloys and their uses are considered. The complete process of building small craft in steel is described in detail in separate chapters on: keels and sterns, framing, plating, decks, superstructures, machinery and piping, tanks and wiring and accommodation and fittings. Maintenance including painting and protective finishes, is fully described. The last chapter examines boat building business, looking at Lloyd's Register of Shipping and The Ship and Boat Builder's National Federation.

The main aim with the SmartPipe R&D project is to develop a concept for online monitoring of the technical condition of offshore pipelines and risers suitable for integration into E-field concepts and integrated process management approaches. This is achieved by developing and linking different technologies into a system for condition monitoring. Parameters to be measured in order to establish a complete condition monitoring system for offshore pipelines have been identified. Based on this the necessary sensor network and sensor principles are evaluated and adapted. Adequate communication infrastructure and concepts for energy supply are also evaluated. Processing of data retrieved from the sensor network are realized through a coupling of numerical analysis tools and improved models for materials degradation reflecting the effects of local conditions and previous load history. The results are presented through a graphical user interface allowing for visualization and the possibilities to run simulations regarding future operation.

A finite element program is developed to analyze the dynamics of buoyancy cans within the centerwell of Spar platforms. The time domain non-linear finite element model includes the effects of the hydrodynamics of the water within the centerwell and the gap between the buoyancy cans and guides. The forces on the buoyancy that can guide structure due to Spar motions are studied in the present paper. The theoretical results are validated with experimental and field measurements. 1:20.89 scale model tests are conducted to measure the buoyancy can motions and guide reaction forces for a range of gap sizes and specified Spar motions. A Spar platform is also instrumented to measure the guide forces in actual field conditions. The prototype field data is analyzed and compared with the numerical predictions.

Modern development tools are now available that provide considerable improvements in design analysis and simulation of intricate engine parts subject to complex loading patterns. These development tools are used in the development process for a new 900 - 1000 rpm marine diesel engine the 'C' type developed by Rolls-Royce Marine Engines-Bergen in a joint programme with Hyundai Heavy Industries of Korea. The new product is defined together with the requirements for a short high-quality development program. Some analytical tools used in the project are described. Some practical experience is discussed with reference to the selected design procedures and analytical methods and some examples from the design validation are presented. Finally the customer benefits of the new engine are outlined and some preliminary performance results are given. Diagrams flow charts and photographs appear on pages 12-16.

Papers presented include - 1. Excessive consumption of lubricating oil on Doxford Engine (Davis A W) 2. Problems of a geared diesel propulsion system (Low D W) 3. Temporary repair of a cracked diesel engine crankshaft (Gatewood A R) 4. Repairs to the fractured cast iron cylinder of a beam air pump (Gatewood A R) 5. Temporary repair of a fractured low pressure turbine rotor (Gatewood A R) 6. Repair of a low pressure turbine rotor (Ross H G) 7. Thermal straightening of turbine rotors (Yates H G) 8. High pressure turbine cylinder casting repair (Falconer W H) 9. Turbine journals - machining in place in wake of carbon packing (Byrne B E M) 10. An improvized balancing operation (Hims H E C) 11. Some further vibration problems relating to ships and their associated machinery (Bunyan T W) (Hildrew B)

The review presented covers gearing problems including metallurgical defects and the bursing of one of the rims in the heart of the bull gear rim forging on a large tanker after only a short spell in service the vibration-induced wearing of tooth flanks of an IP secondary pinion towards the end of the useful life of a twin screw liner and cumulative and eccentric wearing due to indifferent alignment of fine- tooth claw couplings. A case of severe propeller-excited axial vibration is described. and problems encountered with stern bearings including abrasive wear of white metal linings problems with water lubrication and severe damage to the support structure are reported with general guidance given. Vibration of twin screw bossings and cracks in bossing plating and diesel engine failures with engine tie rods and thin-wall bearings are discussed.

In this paper the vibration of an infinite thin fluid-loaded shell with periodic circumferential stiffeners is studied. The stiffeners are idealized as line attachments capable of exerting line forces upon the shell and these forces relate to the coupling of the stiffeners and the shell. The simple harmonic motion of shell and the pressure field in the fluid are described by the Flugge shell equations and Helmholtz equation respectively. By using periodic structure theory the response of this structure to a convected harmonic pressure is studied firstly. The Fourier transforms and the space-harmonic analysis are used to find the response. Then the response to a line circumferential cosine harmonic force is investigated. The concept of vibration power flow is introduced and the influences of the stiffeners' parameters on the power flow are discussed also.

The aftermath of the 1998 Sydney Hobart Yacht Race focused on the question of general seafaring experience versus specific training in the area of sea survival. A study is presented conducted in 1999 at the Australian Maritime College to determine whether there is any observable difference in performance between experienced offshore yacht racing crew members who have been trained in sea survival and those who had not been exposed to this type of training. Practical trials at the AMC Survival Centre are presented as well as assessment trials two weeks after the initial training. Results show that those who received the training had greater knowledge of sea survival and a greater advantage in practical aspects of sea survival than those who did not.

Fiber Moorings are increasingly seen as having significant advantages for use in permanent deepwater moorings and several have now been installed worldwide. They have generally been seen to be of particular advantage in areas where the environmental conditions are modest. However the advantages they offer in good position keeping and relatively easy installation are also attractive in harsh environment locations. In order to be accepted for use in fields such as offshore western Norway a thorough review has been undertaken to determine the level of special consideration that should be given to such locations and the selection of fiber rope moorings that will be suitable for such use. The paper describes the characteristics that need special consideration during specification and comments on the additional work that will be required before such moorings can be used at such locations.

The spectral analysis of nonlinear random wave loadings on circular cylinders is performed in this paper by means of nonlinear spectral analysis. The study is carried out by expressing the wave profile and velocities of water particles as a nonlinear composition of the first order wave profile. Under the assumption of the first order wave profile being a zero-mean Gaussian process the random wave spectra of finite amplitude waves are given. In order to solve the loading spectra of the finite amplitude random waves the drag force is extended into power series of velocity. The loadings of the finite amplitude random waves are then expressed as nonlinear compositions of the first order wave profile and its derivatives. These techniques made it easier to compute the spectral densities of the finite amplitude random wave loadings.

A pc-cluster is set up to compute the free-surface ship flow with affordable cost. Faster hardware is installed in the master node to handle the required data transfer among all computational nodes. Space decomposition strategy is adopted for the parallelisation of computations performed on the pc-cluster. According to the test results using 16 computational nodes the speed-up ratio reaches the value of 8-10 when comparing with the time required by a single node. The time required for a CFD computation is substantially reduced especially for the large grid size. The data transfer rate plays a more important role for the small grid size. The data communication rate becomes a bottleneck in parallel computations. Therefore the data transfer rate of the network and the computation speed of computational nodes should be balanced to give an optimum parallel efficiency for a given problem size.

A preliminary series of full-scale experiments has been conducted in order to investigate flow patterns in pipelines carrying crude oil-water mixtures. A multi-point sampling probe has been designed manufactured and installed in a pipeline. The probe is designed to take samples at several points along the diameter of the pipe. The samples are analyzed in a laboratory for water content in order to obtain the radial water volume profile. The experiments have demonstrated the successful operation of the probe. Both stratified and dispersed flow patterns have been obtained and identified by the water fraction profile analysis. The results obtained have been compared with the predictions based on the linear stability and well-posedness theories.

Today the ship kinetic energy and structural resistance is not taken into account in any damage stability requirements. However the past few years of experience with the HSC code have clearly demonstrated that the grounding damages are indeed related to the operation and the strength of the ship. The present paper discusses various aspects related to rational design against grounding accidents. A relatively simple theory is reviewed for comparing the expected grounding damage of different ships taking into account the structure the displacement and the sailing velocity. It is shown that based on simple requirements of similitude it is possible to scale certain types of grounding bottom damage. Then 130 grounding accidents are investigated.