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Of the oil released by vessels 25 per cent is reported to come from spills and 75 per cent from operational discharges. Oily bilge discharge is second only to oily ballast tank discharge in its contribution. Historically oily bilge water has been treated using OWS (oil-water separator) technology or discharged with minimal treatment. OWS technology alone is not capable of meeting current oily bilge water discharge standards. US military vessels are limited to oily bilge water discharge concentration of 15 ppm under 40 CFR part 1700 UNDS (uniform national discharge standards). International commercial discharge standards appear to be stabilising at 5 ppm. In order for these regulations to have the desired effect of reducing oily bilge water discharge improvements in treatment technology and enforcement must take place. Developments in treatment of oily bilge water and detection of oily discharge from ships are reviewed. New technologies developed to bridge the gap between OWS (oil-water separator) capability of approximately 250 ppm and discharge standard of at most 15 ppm are covered with emphasis on cross-flow membrane filtration technologies and oleophilic PS (polymeric surfactant) infused filtration devices. Developments in detection of oily discharge using SAR (synthetic aperture radar) and enhanced tracking procedures are also reviewed.

A series of articles of noise and vibration includes: Listening to wear and tear - a new approach (a description of a study by Per-Einar Rosenhave of Vestfold College Norway into Acoustic Multivariate Condition Monitoring - AMCM for non-invasive on- or off-line acoustic monitoring of marine rotating machinery); A better design technique for controlling pipework noise (a report of a study at the Centre for Marine and Petroleum Technology coordinated by Marinetech South Ltd aimed at developing applications of Statistical Energy Analysis - SEA techniques to the pipework of ships and offshore installations); Conversion from rigid mounts shows benefits of flexibility (a comparison between rigid and flexible mounted main engines); Bad vibes good vibes! (a discussion by Dr Brian Thomas of VCI of predictive maintenance vibration monitoring programmes including computer vibration analysing software and instrumentation); AC anti-noise concept working on Veendam (ABB Flakt Marine's Active Noise Control system is the first to be applied to shipboard air conditioning).

The containerisation revolution began in 1956 and the use of containers was a big step forward in carrying general cargo by sea. A large amount of exports and imports is now carried by sea in cargo containers. Currently ships are capable of carrying containers stacked higher; however the securing systems are still only capable of securing the bottom 3 or 4 containers. The aim of this study is to understand the dynamic behaviour of container stack on deck during marine cargo transportation. To this end a 3D dynamical model was created - a 20 ft and standard size container were chosen and modelled. In addition a container-securing component called 'twistlock' which connects the two containers was modelled as a non-linear spring. The horizontal and vertical gaps between 'twistlock' and the container's corner casting were incorporated into the model by describing the backlash phenomenon on non-linear spring. In order to simulate the forces of the ship's motion on the containers a rigid base was formed to excite the container and 'twistlock' system. Experimental techniques were used to validate the numerical model. The numerical and experimental results point out enough evidence to support that this model viability.

In the development of ships extensive simulation work is carried out using analytical and numerical methods with FEA (finite element analysis) BEM as well as CFD. An important target of such investigations is the calculation of motion quantities such as velocities and accelerations for a frequency range up to 80 Hz at defined locations of the ship structure which have to be within certain limits. These investigations are typically done by forced response analysis of FEM models. A problematic point for such analysis is the correct prediction of realistic excitation coming from the engine and power train (transmission shaft line and propeller) during engine operation. One common approach is the pre- calculation of frequency spectra of analytically derived excitation applied to a rough engine model. A disadvantage is that realistic operating conditions and interaction of flexible structures of ship engine and moving parts are not covered by such an approach. A calculation methodology is outlined which produces detailed analysis of engine and power train dynamics under operating conditions.

Risk analysis is used in designing ships. A rational method is presented which has been developed for predicting the capsize risk of intact naval frigates. The method requires an accurate and efficient model of ship motions in severe seas. The program Fredyn fulfills this role for naval frigates. For a ship in an irregular seaway the capsize occurrence can be highly dependent upon the wave process realisation. This effect can be modelled by fitting a Gumbel distribution to maximum roll angles from several different seaway realisations. Future improvements to the risk model will include the effects of actions by ship operators to avoid ship capsize.

A new type of marine reduction gear for two or more medium speed diesel engines is described. The reduction gear has been applied to extreme ratings (total ratings between 14 and 34 mw ie 20000 and 46000 hp). Design features are: absolute symmetry of all essential structural elements four point support and cardan shaft characteristics of input shafts. By the use of these features problems which had previously caused difficulties with large ships and reduction gears such as unequal load distribution over the face width and radial displacements of shafts were solved. The input shafts are arranged separately from the hollow pinion shafts and are not supported in bearings but have angular flexibility at either end they taking on the characteristics of a cardan shaft and accommodating radial displacements of up to 2 mm between engine and pinion shaft.

USCG (the US Coast Guard) is tasked in the United States with developing and implementing a program for regulating the discharge of ballast water from ships. It has teamed up with USEPA (US environmental protection agency) to develop testing protocols that will evaluate the effectiveness of technologies to address invasive species present in ballast water. This has progressed to the development of a draft protocol for evaluation of technologies. Proposed experimental design for the verification testing of BWT technologies is addressed. The proposed protocol approach is discussed. Research is identified on the species indicator.

Podded azimuthing propulsors promise benefits in space-saving easier installation passenger and crew comfort manoeuvrability and fuel consumption. Podded propulsors developed by ABB Industry and Kvaerner-Masa Yards (KMY) have been used on Carnival Cruise Line's Fantasy-class vessels Elation and Paradise and Royal Caribbean International's Project Eagle class cruise ships. Systems from Kamewa and Siemens are also discussed. A tool to estimate the performance of various types of thruster is under development. Schottel's new Twin Propeller (STP) Aquamaster's Contaz contra-rotating propeller (CRP) IHI's CRP-DUCK Ulstein's TCNS swing-up thruster and Combi Thruster and OmniThruster Inc's HT series waterjet systems are compared.

A practical system is presented that can accurately calculate the post-buckling strength of ship double-hull structures based on the linear FEM post-buckling using a large-scale structure model of the level of the transverse strength calculation model of the hull. Some application examples are presented. Most ships have adopted a double-hull structure since the recent obligation for tankers to do so. The investigation of the stiffness of panel after elastic buckling is reported as well as the development of a new plate element for equivalent stiffness of buckled panel and the application to the transverse strength calculation of actual double hull structure.

The book provides 'Rapid conversion of cubic feet to long and metric tons'. The tables in the book have been produced to be particularly useful on petroleum tankers where no calculating machines are available. They have been compiled to give weights in long tons against volumes in cubic feet as recorded on the ship's tank capacity scale, with a minimum of calculations required. The tables can be used to work out the weight in long tons loaded or discharged by a ship, or conversely, to determine the volume in cubic feet required to load a given weight in long tons of oil at a specific gravity and temperature.

Conf held 22-23 March 1994 in London UK. Papers are - Pinpointing the critical factors compromising ship safety in a weak market - what can be done Getting to grips with the practicalities and realities of how human factors can enhance and impair ship safety Gaining a better understanding of human behaviour in order to improve emergency procedures Examining the revision of the STCW Convention - working towards more effective manning and training certification Exposing the quality and safety of today's ships to highlight areas for improvement - a classification society's view Clarifying the IACS's contribution to marine safety Overcoming the problems and pitfalls encountered when implementing a quality management system Ship operator and port operator - working together to optimise safety in port

This paper deals with the accessibility for inland shipping to several alternatives for the extension of the Maasvlakte in the Port of Rotterdam (Maasvlakte 2). The accessibility is governed by the risks associated with high wind and wave conditions which can cause structural damage to the ship excessive intake of water and high loads in the coupling cables of push-barge units. This paper discusses the computational methods for the following aspects: wave conditions in the port area; risk of failure in several failure modes and total downtime. The use of interviews with the skippers of the inland ships is discussed. A summary of the results of the study is also presented.

Second Int Symp held in York 11 - 14 May 1971 Papers are Recent developments with respect to codes and regulations relating to the carriage of chemical liquids by sea (including requirements for cargoes with special hazards) Ship design aspects of the safe containment of dangerous chemicals Hazard evaluation Classification and testing and standards of portable tanks for dangerous chemicals Fire prevention and fire fighting for vessels carrying liquid chemicals in bulk Safety measures and plans for emergency action in case of accidents in the Federal German waterways and coastal waters Safe operation of bulk liquid chemical carriers Training personnel for chemical tankers and the importance of skilled operators as opposed to the provision of elaborate equipment The interdependence of port and ship and the need for proper liaison and appropriate bye laws The environment risk arising from the bulk storage of dangerous goods in port areas The control of ships carrying dangerous cargoes in harbours and their approaches Packing standards in relation to performance The effects of containerisation on the transportation of dangerous chemicals Harmonising codes on the carriage of dangerous goods

The problem exists of finding a surface preparation method that is effective yet environmentally acceptable and one that can work on the outer hull as well as on the inside compartments. With the advent of composites for futures shipbuilding a method is needed to remove coatings from the new soft substrates. It is shown how diode lasers have progressed as an affordable and effective decoating tool to be used for shipbuilding and maintenance and as a formidable yet superior system for environmentally sound coatings removal. It is also shown that pulsed high-energy diode laser decoating technology has now progressed to the commercial and economic level of availability necessary to implement into ship corrosion control and maintenance to reduce the overall environmental impact of decoating and to increase productivity of all the ships trades.

Research and development at Lloyd's Register into the field of machinery condition monitoring commenced in the early 1980s with the investigation of the influence of fuel quality on diesel engine wear and corrosion and then progressed through the use of embedded intelligence and the necessary algorithms required in condition monitoring methodologies to the question and fault visibility sensor reliability and the relative advantages of steady and transient condition monitoring. A summary of the major conclusions is presented together with experience gained from the practical application of vibration and integrated machinery condition monitoring systems to ships. The Vibration Monitoring System (VMS) and the newer Integrated Condition Monitoring Systems (ICMS) are compared. Engineering condition monitoring considerations discussed include: fuels research lubricating oil analysis torsional strain signature steady state and transient monitoring research. Data analysis methods include: time series data analysis statistical analysis neural network methods artificial intelligence chaos theory genetic algorithms and qualitative physics.

Methods are evaluated and described for use in reliably selecting and evaluating the MECS (main engine cooling system) of ships. A model of the MECS is set up. A Monte Carlo simulation-based random number generator is then used to produce the maintenance schedule by adopting several distribution types. The influence of component reliability on the reliability of the whole system is evaluated and assessed to find the optimum maintenance schedule. The general scheme of qualitative and quantitative optimisation methods is discussed at the end of the paper. Marine machinery selection is shown to have many considerations requiring a multi-consideration method to provide reliable selection.

The Committee mandate involves concern for environmental and operational loads from waves wind current ice slamming sloshing weight distribution and operational factors. Consideration is given to deterministic and statistical load prediction based on model experiments fullscale measurements and theoretical methods. Uncertainties in load estimations are highlighted. The content of this committees report is dictated by its mandate as well as the expertise of its membership. There is an introductory section. Wave-induced loads on ships are dealt within two different sections namely 2 and 3. Section 2 focuses on two- (2D) and three-dimensional (3D) methods dealing with linear and nonlinear methods and including applications of so called CFD (Computational Fluid Dynamics) methods. Section 3 reviews measurements ice loads and design loads in Classification Societies. Wave-induced loads on offshore structures are reviewed in sections 2 and 4

This paper contains the report of the Committee including methods to determine local and global residual strength. It starts by providing a description of the type of damages that can be found in the various accidental events. Representative scenarios are described and the typical damages that results from the specific accidents are indicated. The next section describes how in real situations the damaged state is perceived. Thus inspection methods are described as well as the available approaches to derive information about the status of the structure from indirect measurements. Loads on the structure are treated afterwards including the loads that are generated during the accidental situation itself and also after the accident when the ship is in damaged state often listed and with non symmetric sections. The loads are used to determine ship strength using the assessment methods described in section 5 which deals with various types of components. The various types of problems raised in repair are dealt with in the following section. Finally the last section deals with salvage and recovery strategies which are necessary in the cases of very large damage in ships.

Reliable estimation of the on-site sea state parameters is essential to decision support systems for safe navigation of ships. The sea state parameters can be estimated by Bayesian Modelling which uses complex-valued FRF (frequency response functions) to estimate the wave spectrum on the basis of measured ship responses. It is therefore interesting to investigate how the filtering aspect introduced by FRF affects the final outcome of the estimation procedures. A study based on numerical generated time series is presented. This study shows that filtering influences the estimations since high frequency components of the wave excitations are not estimated as accurately as lower frequency components. Moreover it is investigated how the final outcome of the Bayesian Modelling is influenced by the accuracy of the FRF. Thus full-scale data is analysed by use of FRF calculated by a 3D time domain code and by closed-form (analytical) expressions respectively. Based on comparisons with wave radar measurements and satellite measurements it is seen that the wave estimations based on closed-form expressions exhibit reasonable energy content but the distribution of energy appears to be incorrect.

Summarized results are presented of the research into the influence of the cooling rate after solution heat treatment on mechanical properties and corrosion resistance of A1Zn5Mg1 and A1Zn5Mg2Zr alloys subjected to artificial precipitation hardening. The chemical composition and mechanical properties of the tested alloys are outlined. Results of research on weld crack sensitivity are provided. Corrosion resistance testing is described. Lastly the research results are analyzed.