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Hydrodynamic and water quality models are used in a predictive capacity to optimise solutions to water quality problems. Three applications of the Delft3D modelling suite (from WL|Delft Hydraulics) are studied. The first application involves dredging-induced turbidity in Saldanha Bay (South African coastline) assessing impact of the turbidity plumes on the sensitive ecology. The second application investigates the feasibility of using seawater for industrial cooling at Saldanha Bay. The third application is the design of a marine outfall discharging a buoyant effluent near Durban. Results and conclusions are presented.

NIMA (the National Imagery and Mapping Agency) set up a project to look at certain national vertical datums in order to evaluate their consistency with orthometric heights derived from GPS (Global Positioning System) (WGS84) ellipsoid heights and EGM96 geoid heights. The project was also to look at the potential for converting bathymetric depths from coastal hydrographic charts to WGS84 depths. The preliminary findings obtained during the initial phases of the project are also discussed. Systematic differences between the EGM96 geoid and various national vertical datums were determined and modelled. These models enable heights to be transformed between local vertical datums and WGS84. A concept for addressing hydrographic chart depth conversion based on GPS positioning of the chart datum (for example mean low low water) is also discussed.

The history of the development of ports shipping shipbuilding and ship repair industries in Australia is described. The shipping industry is traced from its origins in the 18th century when HMS Endeavour entered Botany Bay under the command of Captain Cook through 19th century expansion and the changing patterns of trade and industry in the 20th century to predictions for the 21st century. The main cargoes discussed are agricultural products minerals and oil and gas. Ports at Newcastle Port Kembla Whyalla Kwinana and others are described. Shipping shipbuilding and shiprepairing in the 20th century are discussed in turn. As long as shipping remains the cheapest and most environmentally friendly form of transportation Australia will rely on it for its survival as a developed country. Predictions for the future include the development of new ports to service new industries a reduction in the ship repair industry unless special facilities can be established to compete with Southeast Asia and the development of specialised shipbuilding markets if an indigenous shipbuilding industry is to survive.

Electrochemical tests and immersion tests of welded joints of line pipes in CO2 saturated synthetic sea water were conducted to clarify the mechanism of the preferential corrosion. Also electrochemical potential distributions on the inner surface of two types of linepipes which have different chemistries were analyzed using a two dimensional boundary elements method. In addition corrosion rate distributions in the inner surface were estimated by using the electrochemical potential distributions analyzed and polarization curves of the inner surfaces. After a look at the experimental procedure the results are discussed.

The original Preface of the work states the purpose as being 'to cover adequately the field of naval architecture in one text. The theoretical aspects are thoroughly presented and the discussion is illustrated by practical problems and tables of data. Throughout the work emphasis has been placed on the merchant ship'. Chapters comprise of: Geometry of the ship, Intact stability, Subdivision and stability in damaged conditions, Strength of ships, Load line assignment, Tonnage admeasurement, Resistance and propulsion, Ship manoeuvring and control, The motion of ships in waves, Vibration of ships, Launching and The application of computers to naval architecture calculations.

First conf held in Hawaii on June 3 - 7 1968 Papers are The coming role of oceanography in the nations economy International decade of ocean research Navy and industry cooperation in oceanography Look laboratory of oceanographic engineering Optimum design of marine systems in extreme environment The Catalina test facility Navigation satellites for position determination in ocean areas Federal state and community relationships essential to industrial growth Atomic energys future in food production and the harvest of the sea Propagation loss predictions for ocean test ranges Uses of remote sensing in oceanography The Santa Cruz acoustic range facility "Delos" a mobile instrumented steady sea station Temperature fluctuations in the Santa Catalina Basin Utilisation of pseudo noise for ocean communications AUTEC environmental instrumentation arrays Dynamic evaluation of the Poseidon underwater test facility Deep sea tide and deep sea tide gauges Oceanographic application of magnetic tape recorders Radar utilisation of the ocean test ranges

Seventh symp held in Bath 24 - 27 Sept 1984 Papers are Warship electrical power system controls Propulsion control with microprocessors for ships with DC propulsion motors Microprocessor control of a shaft driven generator based on an induction machine project G I C E N Real time ship power system simulation Simulation of a marine gas turbine power plant Control systems simulation studies for the single role mine hunter Fundamentals of automatic harbour manoeuvring Integrated attitude estimation and tracking A digital control system for ship manoeuvring in ports and waterways A real time ship performance monitoring system Automatic data capture in warships Simultaneous computer assisted data acquisition and evaluation during warship sea trials Mariner surface ship system identification The Ljung innovations filter used for identification of nonlinear ship speed dynamics Prototyping before procurement for machinery control systems Control related problems in digital data bus systems Inter connection between digital data highways Digital data transmission in warships

Simulation-based design increasingly replaces traditional experience-based design. This article gives an overview of techniques now used in advanced industry practice. The article focuses on basics of the techniques illustrating approaches and state of the art with applications taken from the experience of Germanischer Lloyd. It is concluded that the technological progress is rapid both for hardware and software. Simulations for numerous applications now often aid decisions sometimes 'just' for qualitative ranking of solutions sometimes for quantitative 'optimisation' of advanced engineering solutions. Continued validation feedback serves to improve simulation tools as well as it serves to build confidence. However advanced simulation software alone is not enough. Engineering is more than ever the art of modelling finding the right balance between level of detail and resources (time man-power). This modelling often requires intelligence and considerable (collective) experience. The true value offered by advanced engineering service providers lies thus not in software licenses or hardware but in the symbiosis of highly skilled staff and these resources.

Several projects within Sub-Programme III - Trade and commercial Shipping Aspects - are reviewed. These are - Project III.08.1 Assessment of potential cargo from and to Japan via the NSR Project III.1.3 Development of oil and gas exports in northern areas of Russia Project III.2.1 Northern Sea Route and possible regional consequences Project III.5.1 Monitoring commercial trips along the NSR Project III.6.1 Survey of logistics models Project III.7.1 The NSR tariff structure of fees Project III.7.2 The potential of the NSR as a regular cargo service Project III.11.1 New concepts in removing ice and Project III.12.1 Improve information on navigating the NSR.

Probably the most critical factor in the proper selection and application of a liquid overfeed system pump is identification of the system's operating requirements. This includes the required flow rate and the pressure required to deliver that flow rate through the system. An example calculation is given for evaluating both the available and required Net Positive Suction Head (NPSH). Recommendations are made for piping procedures including receiver piping drop leg sizing pump leg velocities suction vent lines and discharge line venting and bypass. Guidance is given on reading centrifugal performance curves because these curves tend to vary between manufacturers. The impact of a system pressure drop is considered and trouble shooting is highlighted.

A large diesel engine has low emissions of everything except NOx. Wartsila Diesel International have been studying practical emission control methods and have concluded that the best are: low NOx combustion direct water injection and compact selective catalytic reduction (SCR). Customers can be offered a choice between different NOx levels and direct water injection can be retrofitted on engines with bore diameters larger than 250 mm. Compact SCR can be applied to all four-stroke engines having low NOx combustion as a base. Gas diesel engines can now be used which offer high thermal efficiency multifuel capabilities the same output irrespective of fuel choice and safe operation as the gas is released only in the cylinder. It is concluded that for a ship to give low emissions it can: have medium-speed engines; have low NOx combustion direct water injection and SCR; have double screws in order to reduce total fuel consumption; have gas engines; and in the future have an integrated engine room with combined technologies for ultimate efficiency.

This paper highlights threatening acts and accidents to shipping transportation activities. Security measures adopted by IMO as proposed in recent SOLAS meetings to safeguard international maritime shipping and ports against terrorist action may not be enough to protect those activities.The aim of the present work is to propose safety arrangements and put forward an alerting system scheme to safeguard marine interests. It will be appreciated by all who are concerned with maritime industrial sectors that in global term protective measures must be taken. Also it must be specified by international conventions to cover all respective and perspective problems leading to the immunity and the neutralisation of threats to marine practices and activities.The author concludes that the proposed alerting system scheme if it were properly adopted globally would therefore lead to safeguard marine activities worldwide against unforeseeable events and abnormal evil acts. Also the author draws attention to one of those events that represents a vital issue regarding the large drastic impact effects on a nation's economy.

The furnace explosion in the auxiliary boiler of a steam driven 300000 dwt VLCC during safety valve testing in 1976 is discussed and model studies of the main and auxiliary boilers and the main boiler flow system using flow visualisation and gas concentration tests are described. Full-scale tests on auxiliary boilers of Foster Wheeler Power Products and main and auxiliary boilers of Babcock & Wilcox using tracer gas techniques and comparison of model and full-sclae data are outlined. The results obtained supported the conclusion that the explosion resulted from the ignition of a gas pocket in the base of the uptake which has been insufficiently purged and that relatively simple modifications to the uptake base together with a realistic purging period would remove the risk of another explosion.

Conf held 29-30 April 1993 in London UK. Papers are - After OPA 90 - understanding national and international oil spill contingency planning legislation Integrating your vessel response plans with your existing quality assurance procedures A rational basis for oil spill response - an environmental perspective The independent tanker owner's view on OPA 90 - vessel response plans Enhancing crew training to improve shipboard emergency response Evaluating the effectiveness of new oil cleanup and control equipment The first 24 hours - the practicalities of drawing up and implementing a detailed contingency plan Drafting defensible contracts between shop owners / managers and response services contractors Conducting and effective response preparedness audit Estimating the impact of vessel response plans - a P & I perspective Understanding the new responsibilities of the charterers - ensuring the chartered vessel has a workable response plan Analysing the effectiveness of modifying ship design and / or onboard equipment to minimise risk

This paper presents the design and qualification work undertaken for the development of seamless and weldable X-65 grade riser sections with thick upset ends. This is one of the four solutions developed and qualified in a JIP during 2004 to 2007. The development effort focused on their application as a design solution for fatigue improvement at the touch down zone (TDZ) of a steel catenary riser (SCR). The manufacturing of riser sections with thick upset ends with weldable properties provided challenges and required specific sets of tooling and considerations in chemical composition manufacturing and heat treatment processes to obtain the required performance. TenarisTamsa undertook the design development and qualification tasks for riser sections with upset ends for two design cases to confirm feasibility of this solution for a range of SCR sizes. This paper presents the overall work done to develop and qualify this solution and key results are discussed.

In order to obtain information on the repeatability of hydroacoustic estimates of abundance and biomass of the fish stocks in Stechlinsee (Germany) and Irrsee (Austria) synchronised surveys were performed in three expert teams using either two identical 120 kHz SIMRAD EY500 echosounders (Stechlinsee) or one such machine and a 200kHz BioSonics DT6000 (Irrsee). It was found that simultaneous surveys by two expert teams using split-beam systems from completely independent manufacturers differing in sound frequency beam width and shape pulse length ping rate acquisition software and post-processing software produce directly comparable biomass estimates. A look is taken at materials and methods. Next results are considered. This is followed by discussion.

A method is presented based on generalised linear models fitted to CPUE data to quantify the changes in fishing power in a fleet targeting a particular species. Changes in the fleet's fishing power are differentiated from variations in population abundance through the use of an abundance index estimated from the CPUE of an index vessel catching the species as by-catch. Observed inter-vessel differences in efficiency are then explained by vessel characteristics. This method is applied to the French bottom-trawlers targeting anglerfish (Lophius budegassa and Lophius piscatorius) in the Bay of Biscay and in the Celtic Sea.

The influence of quasi resonant internal waves with the sea bed on the radar imaging mechanism of submarine sand waves itself is investigated. Simulations of the total Normalized Radar Cross Section (NRCS) modulation caused by sand waves and internal waves as a function of the current gradient or strain rate induced by the internal wave current field at the sea surface have been carried out applying the quasi-steady approximation and linear internal wave theory. After some background information a look is taken at the theory followed by simulation of NRCS modulation.

Hydrocarbon SBFs (synthetic-based fluids) have been used increasingly in a number of industrial applications in particular as lubricants in the oil industry. They comprise a mixture of hydrocarbons with various carbon chains. Their physical properties depend on the chemical compositions and therefore there is a requirement for their structural characterisation and chemical identification. As SBFs are used in large quantities in oil production platforms there is an environmental concern associated with possible toxicity to the marine life. For these reasons there is a need for systems to provide real-time in-situ measurements and characterisation of SBFs. Raman spectroscopy is a technique offering the potential for these measurements. This spectroscopic tool is highly effective in characterising and quantifying chemical species. Some initial results from a miniature Raman sensor are described. This sensor was developed for the in-situ monitoring of SBFs in water.

Current needs in underwater acoustic communication both for civil and military applications are continuously increasing. During recent years GESMA (Groupe d'Etudes Sous-Marines de l'Atlantique) and ENST-Bretagne developed the TRIDENT system (TRIDENT: transmission de donees en temps reel). This is the first real-time acoustic link able to transmit images text and data based on multi-channel blind equalisation. In 1994 a low bit rate speech coder (5.45 kbit per second) was designed and validated for speech acoustic wave transmission in Brest bay. More recently a speech transmission was also successfully realised in July 2003 at sea using the new GESMA-ENST-Bretagne acoustic link. An overview of this project is presented. Firstly the receiver platform is introduced with different implemented functions. Some characteristics of different algorithms are described. Secondly we present main characteristics of speech coder or decoder under consideration for TRIDENT extension. After this some sea trials are described and finally some results are presented.