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A UK Water Company perspective on the WFD (Water Framework Directive) is presented. The WFD will come to play an important part in every part of water management yet many issues remain to be resolved. The directive's issues are listed. Two conclusions are reached. Firstly there is a well defined planning process AMP which Water Companies and others are now organised to plan and deliver. Water Companies would hope that whatever the WFD timetable investment it should be planned using the AMP system. Secondly considerable sums have been and are continuing to be invested - Water Companies and others - will be extremely interested in the cost implications of the WFD - not least because this will impact upon customers and others.

The return rates of normal inexperienced homing pigeons decrease with the increasing distance of displacement. Return rates of pigeons deprived of the sense of smell by bilateral olfactory nerve section reached this low level at only 30 km from home. None of the pigeons returned at distances of 150-180 km. Reasons for this are explored. Recovery data from several series of releases conducted with inexperienced normal and anosmic pigeons at varying distances from the same loft are summarised. The pigeons were analysed under various aspects such as distance of displacement distances covered by the birds angular deviations from home shortening or lengthening of distances towards home angular distributions within the compass scale and time intervals between release and recovery. This does not include original distributions on maps which have been published repeatedly but presents interrelations between various variables deduced from the data. Results are presented.

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.

The finite amplitude waves interaction in water is numerically analysed. This problem can be described using the KZK equation. The mathematical model and some results of numerical investigations are presented. The problem is considered to be an axial symmetric one since the ring-shaped piston was assumed to be the source of two different frequency finite amplitude waves. To solve the problem the finite-difference method is applied. Both the waveform and spectrum of the wave for fixed distances from the source and the pressure amplitude changes for different harmonic components as a function of distance from the source are investigated. Specially normalised pressure amplitudes for difference frequency wave as a function of distance from the source are considered. Numerical analysis shows that the calculation accuracy depends on the value of radius R and the step sizes. The proposed method can be used to analyse the waves interaction in water of different values of source and medium parameters. In addition the computer program allows calculations to be carried out not only for sources with equal surface area of all elements but also to help solve the problem of different numerical parameters.

Environmental matters are a matter of concern for both marine vessel and power plant owners. Almost all emissions from combustion engines are emitted into our atmosphere without being cleaned. This has resulted in a trend toward finding ways of reducing diesel engine NOx emissions the limits of which are set by the IMO and local authorities in various countries. NOx (nitrogen oxides) are the main by-product of the combustion process and contribute to the 'greenhouse effect' ozone depletion and acid rain all of which affect health vegetation and aquatic life. SCR (selective catalytic reduction) is recognised worldwide as the most effective NOx control technology for applications requiring greater than 90 per cent NOx reduction. SCR technology is based on the fact that NOxs can react with nitrogen and water through contact with a reducing agent such as NH3 (ammonia) or (CO(NH2)2) urea in the presence of SINOx catalysts. The SINOx systems are reviewed their background and the advantages they bring to the reduction of environmental pollution.

Estuaries act as a filters between the land and the sea. A coupled 3D-baroclinic hydrodynamic and cohesive sediment transport model is applied to the West Scheldt estuary. The results on intertidal zones are considerably improved by the use of the two-fold sigma coordinate. The simulations give insight to the effects of stratification and its asymmetry into the sediment transport. The calculated density current show an intensity two order of magnitude lower than the residual varotopic currents. The turbidity maximum is not directly associated with the density currents but mainly with the variation of estuarine horizontal area. Numerical results are compared with field measurements at several locations.

Deepwater field developments of the future will face a major challenge of optimising subsea infrastructure while exploring and exploiting oil and gas in deeper waters. Smarter approaches for the selection and operation of optimal subsea production systems will be required. The risks taken in deepwater developments due to an inconsistent approach in performing the outflow analysis are addressed. Since available data may be limited during early stages of design all possible reservoir mechanisms and production system performance should be explored and incorporated into the front-end engineering design process. By having a total system analysis upfront the flexibility and robustness required of subsea infrastructure can be assessed. The importance of conducting total system analysis on the design of a subsea production system for the life of the field is shown.

This session focuses on coastal planning issues that cross between the jurisdictional boundaries of Canada and the US. Opportunities and challenges are examined that are involved in working co-operatively within the Great Lakes basin among the range of stakeholders and agencies to link programmes and initiatives in the context of the broad area of coastal management across the lakes and political boundaries. The planning process and results to date from two selected Great Lakes case studies are focused upon. The first case study examines bi-national efforts to resolve planning and management issues resulting from fluctuating Great Lakes water levels. The second case study is the preparation of a Lake-wide Management Plan to address wide water quality and related land use concerns. The case studies clearly show the challenges and opportunities for trans-boundary coastal ecosystem management for the Great Lakes basin.

The towline tension and unstable motion of disabled and damaged ships is investigated using a geometrical model ship in a towing experiment to establish the estimation method of the towing force and towing method. The towing experiment was carried out both in still water and in waves. The towing resistance coefficients on various kinds of conditions such as towing direction towing speed ship status and towing points were compared in still water. The unstable motion both in regular and irregular waves was also compared with that in still water for sway amplitude yaw amplitude and yaw period. The towing experiment was carried out for both following waves and head waves. Both the unstable motion and the towline tension increase in waves were investigated experimentally.

Fifteenth Int Conf held in Rotterdam 25 - 26 March 1982 Papers are Longer term prospects for world economic development with particular reference to international seaborne trade Relationships between transport seaport and industry - a critical analysis of their evolution in Antwerp and Rotterdam The economic policy of the Dutch government with respect to the Dutch seaport complex Transport flows in the year 2000 - a prediction Oil coal and chemicals - change and chance for Rotterdam The view of Rotterdam on the development of its seaport complex and the trasnportation facilities with the Hinterland The design construction and maintenance of ports Ports in technology Developments in inland transport systems Shipping safety - research by the US coast guard Traffic management in the port of Rotterdam Safety and efficiency aspects of vessel traffic in the port of Rotterdam Safety in the seaport complex Analysis of the risk inherent in the importation of LPG in bulk to four sites in the Netherlands

The Memorandum of Understanding on Port State Control in the Asia-Pacific Region (Tokyo MOU) which came into effect in April 1994, provides for that the maritime authorities in the region co-operate closely to eliminate substandard shipping and to promote maritime safety and protection of the marine environment in the region. The promotion of the PSC Officer Training Course is an essential element for the effective implementation of Tokyo MOU and to ensure uniformity and consistency in port state inspections in the Asia -Pacific region. This textbook is for the use of in-class lectures as well as for the distance education undertaken at officers' own country prior to the intensive course. Contents cover the need for control, the main elements of the convention requirements, documentation, inspection of ships, action by the port state and practical port state control training.

This booklet is part of a series covering the whole of First Year Training and has been prepared to assist instructors and trainees in the development of satisfactory levels of skill and job knowledge required in the Board’s system of First Year Training for craftsman and technicians. This booklet contains examples of additional skills required for mechanical and instrument fitting and assembly. It has chapters on the structure of craft training, the radial arm drill, securing devices, assembly techniques, bearings, gears, keys, springs, pipework, seals and gaskets, inspection and measurement and metal finishing.

A flow law for polar ice is derived which takes into account the effect of deformation-induced anisotropy due to the hexagonal single-crystal symmetry. Attention is focused on the main effect of crystal lattice rotation. A coupled finite element-finite volume approach with only three additional degrees of freedom at each finite element integration point to account for orthotropic material symmetry is used to account for the fabric evolution at the ice sheet scale. Comparison with laboratory and field measurement fabric-data shows good agreement. The model is capable of reproducing the so-called easy and hard glide configurations known from laboratory tests.

The results of studies to simulate the transient performance of an integrated diesel-electric plant installed on a new class of USCG (United States Coast Guard) icebreaker is presented. The three diesel generators provide all of the power to the ship’s loads including the electric podded propulsors. Model elements included the diesel generators power electronics podded propulsors ship electrical loads and the hydrodynamics. Case studies include free-water crash back ice ramming ice milling ice jammed propellor and ballast pull. The results show that integrated diesel- electric propulsion plants with podded propulsors have unique control system requirements if the maximum performance of the diesel engines and ship are to be realised. The models are described and the results of the simulations and conclusions are presented.

A systematic procedure for properly treating each of the two broad types of uncertainty aleatory and epistemic is proposed for the risk-based design of marine structures and illustrated with the formulation of optimal design of a typical offshore platform in the Gulf of Mexico. Randomness in the ocean wave height at the offshore site of a platform and the variabilities of material properties contribute to the aleatory uncertainty whereas the epistemic uncertainty includes the imperfections in the modeling and calculations of the structural response and damage estimation. Optimal design is then formulated on the basis of minimum life-cycle cost (LCC) in which additional epistemic uncertainties in the life-cycle cost components are also included.

The Navy's current emphasis on broadband sonar signal processing and frequency agility has prompted the need for new classes of broadband sonar transducers that can transmit these complex signals. The development of new broadband triply resonant transducers is presented. The theory of operation design fabrication and test results are reported. The transducer designs use multiple passive components (masses and compliances) added to a conventional-type Tonpilz transducer to produce triply resonant transducer devices. The designs have the ability to produce lower frequency capabilities from a small package (Element Size) than current traditional Tonpilz transducer of the same size and weight. The increase in operating bandwidth is achieved without using exotic expensive transduction materials making the designs cost effective. These Triple Resonant Transducers provide 5 kHz to 10 kHz increase in bandwidth at the low end of the band over a traditional Tonpilz transducer and have a broadband operating bandwidth from 13 kHz to 37 kHz.

Slope stability evaluation in the steep areas of the Fensfjord is described. Appropriate undrained shear strength for static and dynamic stability analysis was established a reasonable prediction of earthquake induced permanent deformation was made and post earthquake static stability was evaluated. Analysis of gravel supports on soft clay showed that three supports needed counter fills in order to fulfill design requirements. At the tunnel entrance point of the pipeline at Mongstad the soft clay at the seabed had to be excavated in order to attain satisfactory stability for the gravel support.

Seismic reservoir monitoring is effective in helping to understand the dynamic behaviour of reservoirs and in reservoir management. Perturbations (errors and differences) between different phases of a 4D seismic study create noise when datasets acquired at different times are analysed to detect changes in the subsurface. This noise can mask the subtile variations in the seismic response of the reservoir that indicate changes in pore fluids. The feasibility studies leading to the development specifications of Q-Marine include a significant effort to study and quantify the effects of these perturbations. The new technology is described and examples are shown of the ability to remove the perturbations experienced in conventional seismic data. Diagrams appear on pages 5 to 7.

The topic for consideration by committee VI.2 was ultimate hull girder strength looking at evaluating and developing procedures for estimating the ultimate strength of ship hull girders. Consideration was given to relevant load combinations including overall bending torsion and shear as well as to local pressure loads. The influence of fabrication imperfections corrosion and in-service damage on the strength was discussed. The procedures were assessed by comparison with model tests and more refined calculation methods. Recommendations for ultimate strength assessment methods were given. In the discussion of the committee's report the following topics were considered: types and theoretical background of approximate analyses for ultimate strength; ISUM of first and second generations; evaluation of analysis methods for ultimate hull girder strength and questions; and finally ultimate hull girder strength and deformation capacity. The presentation is followed by some floor and written discussions and a reply by the committee.

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.