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The need for the current aviation terrestrial navigation infrastructure to evolve in order to provide a reversionary option for navigation for the RNAV/RNP-RNAV operational environment envisaged for 2010 onwards is examined. An overview of the current infrastructure performance with regards to multi-DME (including VOR/DME and TACAN) coverage redundancy is given. Next some of the issues that have been identified in Phase One of the study relating to aeronautical information DME ground infrastructure and service providers is covered. The EUROCONTROL Navigation Strategy anticipates that VORs will be decommissioned by 2010 the impact of this on operators is discussed and options for decommissioning are provided. A summary of the findings of the study so far is given.

Between 1985 and 1988 the meio- and macrobenthos of the Polish part of the Szczecin Lagoon a eutrophic and polluted Southern Baltic-connected coastal water body was studied. The results showed a peculiar variability in the meio- and macrobenthos - regardless of spatial and seasonal changes within each year the year-to-year variations involved high abundance and biomass values in the first year of study much reduced values in the second and third and a seemingly slow pick-up in the fourth and final year. The recent awareness of and emphasis on climate- and hydrology-induced variability in biotic components of numerous aquatic ecosystems has led to a reassessment of the data. This study explores whether benthic communities while showing spatial and seasonal variability also responds to modulation by interannual variability of climatic and hydrological processes.

The AUVLAB (autonomous underwater vehicle laboratory) at MIT (the Massachusetts Institute of Technology) is currently building and testing a new general purpose inexpensive 6000 metre capable HAUV (hovering autonomous underwater vehicle) the 'ODYSSEY 4 class'. The vehicle is intended for rapid deployments potentially with minimal navigation thus supporting episodic dives for exploratory missions. For that the vehicle is capable of fast dive times short survey on bottom and simple navigation. The vehicle is introduced and a mission scenario given. The design features required are detailed followed by the design achievements. Finally the navigation and payload are described.

A comprehensive CZMP (coastal zone management plan) has been prepared for the Jumeirah Coastline from the Dry Docks to Jebel Ali Port. The Plan provides for the stabilisation of the coast through a comprehensive programme of coastal engineering works. The principle underlying the works has generally been to achieve stable coastal alignments through reorientation of the shoreline. The stabilised shoreline will provide the basis for development of the recreational and amenity potential of the coast to serve the needs of the national and international populations into the future. The coastal management issues and major study elements that contributed to the development of the CSMP are outlined. The main elements of the CZMP are described focussing on the strategy for the sustainable defence and management of the Jumeirah coastline Dubai.

A new gas engine concept for cogeneration in the range of 200 kWcl is described. Cooled EGR is used together with excess air and turbocharging to explore the potential of this approach in comparison to pure lean burn combustion with regard to thermal efficiency and NOX-CO trade off. Then the new engine process is introduced which includes stoichiometric operation 3-way catalyst cooled EGR of up to 25% and turbocharging. The results show a new record in engine efficiency and NOx emissions. The robustness of this new engine processes has been demonstrated for six widely varying compositions of natural gas fuel. In addition the mechanical and thermal stress of critical components has been shown to not exceed those of the same engine in DI-diesel operation even up to the highest power output. Finally based on a detailed thermodynamic process analysis this approach can be extrapolated to larger engine sizes and power ranges.

Within an EEZ the range of activities is extremely diverse covering duties under the headings of Fishery Management Maintenance of Law and Order Safety of Navigation and Transit and Protection of the Environment. The majority of these duties are non-military and many are "commercial workboat" activities. Each nation approaches these duties from a different perspective partly dependent on their existing infrastructure and services and approach to policing; hence some might use military or paramilitary resources to undertake non-military roles. This paper describes a unique ship that has the versatility to address the entire spectrum of EEZ management challenges across an extensive range of scenarios that encapsulate the diverse EEZ roles. The paper refers to the scenario based approach to developing the concept of operations for the vessel and thus how the design evolved to provide effective performance in each scenario. A technical description of the ship is provided with an explanation of each of the key features. It is proposed that COHORT provides the basis for a family of future-proof EEZ management vessels offering exceptional value for money though high utilisation.

Technology of today can address the shortcomings of the concepts in the past. The early stages of ship design offer the largest impact on the affordability in the design of a ship and its systems. Due to the recent spike in oil prices the back-fit of energy-saving systems has drawn new interest by shipowners the US Navy included. In an effort to operate an affordable fleet many new ideas have been generated. This paper looks to the past to reveal energy-saving concepts of the last energy crisis. These concepts generated in the mid to late 1970s did not achieve their goals once the cost of fuel dropped and the immediate affordability metric did not justify their adoption. These old ideas in the technologies areas of energy monitoring hull roughness and waste heat are reviewed to identify their weaknesses in adoption if any. The identified weaknesses are paired with new technology to address these concerns. These old ideas with new technologies are also looked at for new acquisition programmes where the costs associated with back-fit are no loner applicable.

Deepwater pipelines are normally subjected to external pressure and bending. They fail due to structural collapse when the external loading exceeds the pipes collapse limit surface. For seamless steel pipes the influence on this limit surface of manufacturing imperfections has been thoroughly studied using finite element models that have been validated via laboratory full-scale tests. If by accident the collapse is initiated at a certain location the collapse is either restrained to the collapse initiation section or it propagates along the pipeline. The latter is the most detrimental for the pipeline integrity. Since the external collapse propagation pressure is usually quite low compared to the external collapse pressure it is necessary to build in the pipeline spaced reinforcements usually steel rings to act as arrestors for the collapse propagation. Using finite element models it is possible to determine the crossover external pressure of different pipeline arrestor designs. Here these finite element models are discussed and validated by comparing their results with experimental determinations. The flipping and flattening crossover mechanisms are considered in the experimental validation of the numerical models.

There has been a tendency over the last few years to develop ships capable of carrying several different types of cargo. This paper describes combination gas and chemical tankers. The liquids they can carry include oil products acids and edible liquids such as wine and vegetable oils. The SOLAS MARPOL and IMO safety rules applicable to such ships are outlined. The special arrangements for cargo containment cargo handling and safety are reported. Amongst factors considered are cargo tank design cargo tank insulation piping systems cargo transfer facilities cargo temperature control venting systems cargo monitoring instrumentation and fire-fighting installations. So far 10 such ships have been built with independant pressurized cargo tanks made of stainless steel and a further 5 are on order or under construction.

Marine diesel engines burning heavy fuels with a high level of efficiency are preferred for the propulsion of sea-going vessels. After ratification of the first international regulations on the limitation of gaseous emissions for marine diesel engines a tightening of the limits is to be expected in 2010 (IMO Tier 2) and in 2015 (IMO Tier 3). This article describes investigations carried out at MAN Diesel SE to reduce emissions of medium-speed diesel engines. The aim of the experiments was to show which technology is required for engines with a mean effective pressure of mep 26 bar in order to fulfil the future emission limits with no change in fuel consumption. Only those results are presented which come from in-engine measures. This is because the external measures currently known such as a fuel-water emulsion or SCR catalytic converters require basic conditions concerning fuel quality etc which are actually not usual.

The approach to geotechnical design and the comparison of penetration resistance with measured resistance for 20 suction anchors installed at the Njord Field in the North Sea during summer 1997 is considered. Measurements were carried out using a dedicated data acquisition system which produced detailed real-time information on a computer display during the installation. Also included are comparisons of penetration resistance with measured resistance for some of the 16 suction anchors installed at the Visund Field in the North Sea during autumn 1997.

Many modifications to crosshead diesel engine designs have been made in recent years. The higher power output increases the thermal loading in the combustion chamber and cylinder lube oils are therefore exposed to increased thermal stress. At higher temperatures oils can oxidise and form oil-insoluble resins which bind soot and other insolubles to form piston deposits. Extensive field testing is conducted on detergents for cylinder oils in crosshead diesel engines. The test vessels and engines are described and how piston deposit and wear measurements are made. The results show a consistent difference between two major detergents in both deposit and wear control. Piston deposits form quickly and heavy deposits are shown to lead to higher wear rates. A comparison is made between the results from the field tests and those obtained in laboratory and engine tests.

As high-speed craft are increasingly being used it becomes important to ensure the safety and comfort of passengers and cargo. Ship motion can be a serious problem. Optimisation of the vessel for motion response is done at the design stage usually by means of prediction software and model tests. Model tests are note cheap and at an early stage designers depend mostly on computer programs. So it is important to check how different the results can be when using different methods: the 2D frequency domain with different strip theory and 3D frequency domain translating pulsating source technique are outlined and applied to the motion prediction of two high-speed vessels as they travel in head seas at two different Froude numbers. The results obtained from these theoretical calculations are correlated with each other as well as with experimental data. The theoretical and experimental results are then compared and discussed. Finally recommendations are given for the applicability of the various methods.

A comparison of two methods which detect oil in produced water is presented. The methods are the Freon-IR method and the new draft ISO standard GC-FID method. The environmental impact of produced water is considered and diagrams show risk factors from discharge. It is explained how work was done on three oilfields and one gas-condensate field. The materials and method are described including the produced water the sampling procedure and the analytical methods. Each lab received three samples from each field. The samples were analysed offshore initially and then onshore at Westlab both using the Freon-IR method and then finally onshore by at SINTEF using the GC-FID method. Results are tabulated and discussed. It is concluded that the reported values are considerably lower using the GC-FID method.

Preliminary conceptual design of hulls is developed and a theoretical evaluation study carried out to compare hull concepts. Systematic variation of the side hull location is performed using CFD computation to find an optimum position for side hulls for a trimaran. In order to compare computed results a model test of trimaran was carried out. Shallow water effect is considered due to the route which has critical water depth of 20 m for the design speed and investigated on the condition of different speeds and water depth by the numerical computations.

In 2001 NIMA (the National Imagery and Mapping Agency) initiated a project with the Naval Surface Warfare Centre. This had two main aims: to examine transformations from national vertical data to the WGS (World Geodetic System) 1984; and to address the potential for converting bathymetric depths from coastal hydrographic charts to WGS 84. The findings obtained during the project are discussed. Systematic differences between various national vertical data and WGS 84 are determined and modelled. These models enable elevations or orthometric heights to be transformed with a better 'fit' between local vertical data and the WGS 84 geoid. A concept for addressing hydrographic chart depth conversion based on GPS positioning of the chart data (e.g. Mean Low Low Water) is also examined. Results along the southeastern US States coast are presented.

This paper presents a component-based method for model test planning and analysis tool validation. This method provides a direct approach for analysis tool validation based on the correct modeling of fundamental physics of each component. With this method we validate the analysis tools at model-scale i.e. the geometry and physical properties of floaters mooring lines and risers are modeled exactly the same as those tested in model wave basin. We derive the model-scale viscous force coefficients of floaters risers and mooring lines directly from the model test and input them into the validation analysis. By doing this we eliminate scale effects involved in the validation. This helps avoid the mis-interpretation of model test data in establishing key parameters in full-scale design. We present two examples to demonstrate the validation approach: FPSO roll and deepwater CALM buoy-mooring-riser coupled motions. The examples show the importance of consistent numerical and physical modeling in validation of design software tools. Validation of the analysis tools is essential for confident design.

In recent years there has been a major interest in the development qualification and commercialisation of composite production and drilling risers for deepwater offshore applications. Two business cases are presented showing the economic benefits of using composite risers on TLPs and SPARs. The current status of the composite riser technology is reviewed together with recent advances. In addition the key learnings from the Heidrun TLP demonstration project are highlighted as well as how these learnings are being addressed in the P-17 demonstration project. Also discussed are the current efforts to commercialise composite risers.

Southampton Water an estuary on the south coast of England has been the focus of several studies to determine the seasonality and productivity of its pelagic community. However the meroplankton component and in particular the cirrepedes have been largely ignored though they rank second to the Copepoda in abundance. In order to estimate the contribution of barnacle larvae to the pelagic community 42 quantitative zooplankton samples were collected from a fixed station within the estuary from January 2001 to July 2002. Eliminius modestus were the most abundant barnacle larvae during the summer months. A look is taken at materials and methods followed by results and discussion.

AUV design is a relatively new research field and generally AUVs are designed to suit a specific mission. Most AUVs are designed from scratch and with little design history and experience to draw upon. An important step in the conceptual design of AUV is AUV sizing (determining the external dimensions to match the mission requirements). These dimensions are dependent on the characteristics of the mission the operating environment and the chosen technology. To speed up the design process computer-based design tools are used to generate a conceptual design which in is then further refined by calculations and validations. A computer-based design-tool is presented which integrates all major design parameters to allow an efficient and rapid trade-off analysis between various options for example different battery types etc. In order to carry out fast modelling different types of battery fuel cell and semi-fuel cell options to power the AUV are pre-programmed in the dimensioning module and can be selected by the designer.