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The quantification and identification of algal photosynthetic accessory pigments from natural water samples to assess algal population structure and composition is an active area of aquatic ecosystem research. As part of this work image data from NASA's high-altitude flown hyperspectral sensor AVIRIS (airborne visible- infrared imaging spectrometer) were acquired of salt evaporation ponds near south San Francisco Bay. The image data were processed as spectra and analysed for detection of algal and photosynthetic bacterial accessory pigments. The overall spectral characteristics of the ponds allowed identification as to population composition corroborated by salinity data and parallel research on hypersaline ponds in Baja California Mexico.

The new generation of concrete armouring units CORE-LOC as a single layer armour has been in use for less than a decade with only a handful of breakwaters built. The design of the Caleta La Mision Breakwater in Argentina is considered. Conclusions from the design process are presented. These are supported by extensive physical model testing in both wave flume and basin for verification and optimisation. The design of the front face is considered together with special toe hold blocks overtopping and rear side stability as well as special roundhead features. On the reclamation behind the structure a special trench for the drainage of overtopping water was introduced as a special structural element. Flume model tests and 3D physical model tests are presented followed by conclusions.

This paper provides details of the development of new and existing techniques for real-time transmission of ADCP data via strain bearing data cables in water depths exceeding 6000ft. Reliable transmission of the data via a hardwired link with complete redundancy requires complex design to satisfy actual requirements. The requirements of the system include location of two ADCPs to avoid not just physical interference but also acoustic interference one on the seabed and one at 500m above seabed with 100% data and power redundancy using an existing 5000m of communications infrastructure and a limited number of copper lines. Furthermore the requirements for a realtime link between the seabed frame and a buoy mounted ADCP using a 500m strain bearing armored data cable and the challenges of the associated weight & buoyancy requirements are discussed. The challenges created by these requirements and constraints and solutions developed are presented in this paper.

A numerical model is presented to predict the interaction of multidirectional random surface waves with one or more trapezoidal submarine pits. In the present formulation each pit may have a different side slope while the four side slopes at the interior edge of any given pit are assumed equal. The water depth in the fluid region exterior to the pits is taken to be uniform and the solution method for a random wave system involves the superposition of linear-wave diffraction solutions based on a two-dimensional boundary integral equation approach. The incident wave conditions are specified using a discrete form of the Mitsuyasu directional spectrum. The results of the present numerical model have been compared with those of previous theoretical studies for regular and random wave diffraction by single or multiple rectangular pits.

Slow and medium-speed diesel engines were investigated in the MCR power ranges of 6 9 and 13.5 MW and a comparison figure of cost per tonne mile for an assumed voyage profile was calculated. Ways of making cost savings in auxiliary electrical and steam heating power systems are also investigated. It is concluded that slow and medium- speed engines in the installed power range 8.5-9.5 MW present the most favourable economic return over a 15-year life cycle but that this relatively low installed power combined with reduced exhaust temperatures in the latest series of slow-speed engines means that the at-sea electrical load can not be satisfied using an exhaust gas waste heat boiler turbogenerator unit. Operating diesel generators on cheaper fuel grades under the assumed economic conditions would offer more advantages than fitting a shaft genarator.

The progress of the Electric Ship Programme over the last year is reviewed. The significance of individual equipment efficiencies on fuel consumption are indicated and some of the technological developments which can be adopted to minimise losses in the Electric Warship architectures are described. A brief description of the Royal Navy's Permanent Magnet Propulsion Motor (PMPM) is presented. The need for and advantages of reduced fuel consumption are discussed and the scalpel a Prime Mover Running Cost Model for assessing the annual operating costs for fuel repair maintenance and overhaul is described. Both power electronics device and converter design offer much greater efficiency. The development of IGBT and MOSFET Controlled Thyristor (MCT) is discussed along with alternative power electronics devices: Integrated Gate Commutating Thyristor (IGCT) MOS Turn Off Thyristor (MTO) and Emitter Turn Off thyristor (ETO). The matrix converter appears most suited to a zonal power distribution application but the possibility of its use for higher powers is being actively pursued. Matrix converters and PWM converters are compared and sequential capacitive discharge power conversion discussed.

The design status and service experience of MAN B&W Diesel's computer-controlled low-speed crosshead diesel engines are considered together with the application prospects for such 'intelligent engines' now designated as the ME series of engines. The main development goals have enhanced reliability reduced operational costs and wide flexibility with regard to engine operation and emissions. The ME system is outlined and the electronic control system with details of its main building blocks and the safety features and principles is described. A full-scale service test of the ME system on all cylinders of the 6L60MC main engine of the 37500 dwt Norwegian chemical carrier M-T Bow Cecil was started in November 2000 and more than 10000 hours have been logged. The design of the systems used in the service test is outlined followed by a description of the service experience obtained. Finally installation aspects related to the commercial ME series of engines of which the first engine was test run in February 2003 are outlined.

This paper deals with the evolution of the English Star Class of vessel. The commercial background which led to the technical decisions on capacity dimensions layout and performance characteristics is outlined . The close relationship between the naval architectural and marine engineering features is described. These features are mostly evolutionary rather than revolutionary in character and represent a significant step forward in the `efficient ship' concept in terms of manning levels operation fuel consumption and performance. A detailed description is given of the refrigeration propulsion and auxiliary machinery. The vessels performance during sea trials are reported and experience gained with the 1st vessel of the class during its 1st year of operation are recorded.

This paper presents a derivation of the Maximum Likelihood (ML) detector for acoustic signals that have propagated through a random or uncertain ocean environment. The derivation requires probability distribution functions (pdfs) of relevant signal and noise parameters belonging to the exponential class. The resultant ML detector operates on the observations to compute parameter means referred to as conditional mean estimates (CMEs) and then correlates the CME with the observations to obtain a detection statistic. For this reason the detector is referred to as an Estimated Ocean Detector (EOD). For Gaussian signal and noise the EOD reduces to the weighted sum of a correlation detector (CD) and an energy detector (ED) which agrees with Van Trees' result. The EOD is shown to be a promising method for improving passive sonar performance by directly incorporating available information about the ocean environment without sacrificing robustness to errors in the signal parameter distributions.

The legislation of the use of tugs in sensitive waterways was initiated without a thorough understanding of the forces and actions involved particularly at higher speeds. The use of indirect mode towing to generate very high line tensions demands a tug with hull characteristics which did not exist before requires a manoeuvre which is the opposite of what was previously deemed safe. Here the development of this class of tug is traced with a focus on the program of model testing and computer simulation studies. This has led to the design and construction of one of the most powerful and effective escort tugs in the world due for delivery in May 2000. Also discussed are other developments which have enabled more conventional tugs to safely provide a much-improved escort towing capability. In conclusion the need for a uniform international standard by which the performance of escort tugs can be accurately evaluated and rated is examined.

Some of the issues associated with ensuring that a structure has an adequate airgap are considered as well as the loads experienced by a structure once the airgap has been exceeded. The traditional approach to setting the airgap on installations which have been designed or assessed for use in UK waters is reviewed and compared to the requirements of the recently issued Design and Constructions etc Regulations. The adequacy of the traditional approach is considered through the use of a joint probabilities surface elevation model. The status of a number of ongoing HSE funded studies which are expected to contribute to the development of a more rational approach to the setting of airgap are reviewed. Also considered is how the airgap determination can be approached in the overall context of ensuring that the risk to personnel resulting from structural (environmental) overload or wave deck inundation is as low as is reasonably possible.

FITNET is a four-year European thematic network with the objective of developing and extending the use of fitness-for-service (FFS) procedures for welded and non-welded metallic structures throughout Europe. The aim of this paper is to present the features main analysis routes and major areas of technical development pertinent to the Fracture Module of the FITNET FFS Procedure. The procedure is based on previous developments carried out within the SINTAP project as well as advances in other standards such as the British Energy R6 rev 4 and the current amendments to the British Standard BS7910. In addition the work from other EU projects has been used to extend the treatment of several problem areas such as the effect of constraint and the treatment of thin walled structures.

LNG now represents about one third of internationally traded gas. Its growth continues. Evidence is presented to illustrate this growth. The main trends are examined - what are the underlying processes that make these changes happen on a global scale? It is forecast that business will continue to grow fast in the Atlantic and Pacific Basins and that cost reduction will continue. It is also concluded that short-term trade is here to stay and will form an increasing percentage of the global LNG business. It is highlighted that there is likely to be an impact upon project funding as increased project risks are diminishing the support for project financing and driving up its costs. Project sponsors will increasingly be asked to provide sizeable equity.

SAIC's Marine Operations Division developed an internal research and development project to design integrate and install a cabled observatory in the Chesapeake Bay to address regional environmental and security issues. Cabling a multi-sensor buoy / mooring with each sensor possessing different data and power requirements was a challenging exercise. The Goodwin/York Research Observatory (GYRO) system transmits real-time and continuous data collected for both surface and subsurface conditions. The buoy is integrated with a suite of complex and diverse sensors on a common power grid and telemetry scheme. After some introductory information a look is taken at the GYRO and the system installation. A description is given of the NOMAD buoy and the Goodwin Island site. Data products and future goals are also considered.

An overview of the project to create the HNLMS Rotterdam is presented. Firstly a brief introduction is given describing how the project was executed. Then detailed information is presented on the design philosophy of the Rotterdam and the way the project developed in the course of the years from concept design to reality. Finally the lessons learned so far are considered. Special attention is paid to the logistic concept which led to the internal arrangement and layout of the ship. In addition the design of the well dock is explained as special features were added to the design to improve operations for landing craft. Extensive model tests were carried out to ensure that the well dock met the design criteria. The Rotterdam is built mainly according to commercial rules and regulations. The extent to which these regulations are implemented in the design is also discussed. A brief explanation is given about the major design decisions. The Rotterdam is the first LPD in the world with Diesel-electric propulsion.

The effects of Boring and Trepanning Association (BTA) deep hole drilling conditions on hole profile in deep hole machined work piece are analyzed by domain analysis methodology. The mechanism and the cause of multi lobe shaped hole profile are discussed. The relationship between the profile of deep hole drilled work piece and the cutting speed the feed rate the chip flow the tool wear etc is investigated. These and the cause of tool wear are studied in the case of SUS 316 stainless steel.

The Hybrid Catenary Riser (HCR) is a novel idea synergising advantages of both flexible and rigid pipes. The paper presents the concept in detail and identifies its technical and economical advantages. This is illustrated by two designs for deep water fields. For these study cases the HCR is compared to all-flexible risers and SCR's both on technical and economical grounds. The installation of the HCR requires a pipelay vessel with lay capacity of both flexible and rigid pipe. This aspect is also addressed including the presentation of this unique capability of CSO's new pipelay vessel the CSO Deep Blue.

Fire and explosions represent a large number of maritime casualties and often ship loss. On-board fires often start in the engine room. ERS (engine room simulators) have improved greatly in recent years and are becoming very realistic. Understanding fire behaviour and its development during an emergency allows the users to understand better and respond more efficiently to such emergencies. The first idea of the article is to use adequately prepared CFD models for the observed engine room geometry initial and boundary conditions and to prepare some of the most likely scenarios of fire occurrence. Results are intended to be an understanding of the circumstances that occurred to educate engineers and to present the possibility of ERS upgrade with fire models. The second idea is the discussion of the full integration of CFD model in ERS and the possibility of user interaction during the simulation process.

Standards permeate the work of all areas of the marine industry whether in design construction operation or individual professional competence. Some observations intended to provoke thought on the importance of International Standards in the marine industry are provided. The importance of common international standards is highlighted. First the roles of the IMO (International Maritime Organisation) and the Classification Societies are explored. Next the key responsibility of the competent individual professional engineer in delivering those standards is emphasised. Finally it the focus turns to the vital role of societies and institutions in assessing competence and developing registers and agreements that will permit the free movement of the practising professional engineer around the world. In conclusion the important role of societies and institutions in the future development of the industry and its professionals in relation to standard setting is emphasised.

The superseded gear standard BS 436 (1940) and the effect this has had on gear design in the UK is considered. The theoretical basis of the new standards is explained and the empirical factors to take account of the actual stressing of real gears are discussed. The use of the new standards as design tools is illustrated by a number of examples to show how the effect of gear accuracy mounting arrangement lead correction and material quality can be quantified. The role of the new procedures in developing better specifications for marine gears is touched upon. The paper concludes by noting the recent changes in the gearing industry and the revival of interest in gear research.