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Hydrocarbon explosions in offshore modules have been the subjects of a wide range of experimental research. Until recently this experimental work had investigated overpressures developed within a gas-filled module under idealised conditions. However it is unlikely that such an idealised situation would occur during a real offshore hydrocarbon release and until recently little information was available to allow the assessment of the risk associated with the ignition of a gas cloud produced by a realistic release. To address this recent research projects have investigated the build-up of gas within a naturally ventilated module and the consequences of the ignition of such a gas build-up. Marathon Oil have analysed the data produced by these experiments and have used this to develop an empirical model to evaluate the risk associated with has build-up and explosions in naturally ventilated offshore modules. This model is presented. It is called OMEN (open module explosion tool). Based on simple module geometry parameters it allows assessment of potential explosion risks at an early stage in design. It may be used to assess the tolerability of the residual risk of an existing platform or as a screening tool for modules where detailed computerised geometry files are unavailable.

In transportation by sea for economy a two-stroke diesel engine and a low-grade heavy oil have been used because of high thermal efficiency and cheapness of fuel price. However some marine engines have been damaged by scuffing of the piston ring and the cylinder liner of the engine. It is very difficult to establish the reasons for this. At present no index is available to define overall combustion characteristics from ignition to the end of the combustion. In order to solve problems experienced by Takasaki a combustion facility was newly developed to investigate the combustion characteristics of bunker fuel. At first the effect of injection pressure on the flame behaviour was investigated. The injection system was reformed to show a flat pressure during injection and sharp decrease at close of the nozzle using a marine diesel fuel. The spray flame burns almost the same for every experimental run. Next a bunker fuel was used to test the flame characteristics after the end of injection. By analysing the images the characteristics of the flame quenching such as the time of flame quenching after the end of the injection and the location where the flame disappeared are obtained. Under the same conditions the flame characteristics showed almost the same. As a result

AMOEBA (advanced multiple organised experimental basin) is a plunger-type absorbing wave maker using a VCM (voice coil motor) system as the driving equipment. It is small and mobile because of the simple mechanism of the VCM and it can theoretically achieve perfect absorption of regular waves. Fifty units of the wave maker have been placed along the periphery of a basin of diameter 1.6 m. However the disadvantage of the VCM system is that it is difficult to make a VCM that can handle high power and large stroke so it is difficult to make the wave basin large. However if the viscosity is neglected according to potential theory it is possible to carry out experiments with small models in a small basin. By using the small basin the cost of development of ship and ocean platforms can be reduced. In particular it is expected that the small basin will be a useful tool for development together with numerical calculations. To substantiate the above arguments measurement results of the wave diffraction force acting on a ship or ocean structure model in the small basin are presented. Several models were used including a sphere a pontoon a cylinder a ship and a semi-submersible. The main length of each model was about 0.3 m one-tenth the size of a model in an ordinary large basin. The usefulness of the AMOEBA is shown by comparing the experimental results with calculated results which have in turn been corroborated by experiments in a large basin.

Modelling the traffic system development is extremely significant and depends directly both on general and special objectives of the economic and overall social development. The employment status in the traffic system is an essential element of its organization. The personnel potential certainly represents a crucial resource of any country and thus in the traffic and transport sector it also represents a key factor of development especially of its technological and economic stratum. Similarly the status and level of employment in the traffic system affect the productivity of work in the subsystems as well as in the overall system. The following areas are considered: the employment status in the Croatian traffic system (absolute and relative share of sub-systems in the structure; the employment dynamics of the traffic systems and their subsystems regarding the status in 1992 and 2002; the change in the employment structure in the traffic system regarding their subsystems and the status in 1992 and 2002; the formation of the mathematical prognostic trend models of the employment development of single traffic subsystems and traffic system in general as a scientifically founded basis for forecasting of this traffic value in the future. It is concluded that the established mathematical prognostic trend models that are statistically significant represent the scientifically founded basis for forecasting the number of employees in the traffic system of the Republic of Croatia in tX14582 Employment of combined carriers

The deep-sea overnight cruise industry is the fastest growing segment of the maritime industry with annual growth rates of eight to ten percent. Regulatory and public interest in the potential impacts of cruise ship operations on the environment continues to draw significant attention. The environmentally sound and legally compliant operation of its ships is a priority of cruise ship operators. The changing legal landscape increasing public interest the activities of a number of interested parties ship operational requirements technical innovations and evolving environmental sensitivity are some of the specific aspects of the overall cruise ship environmental issue. The complex legal regime in which the industry currently must operate is described together with the methods the cruise industry uses to meet these stringent environmental requirements. Included is a discussion of current engineering and operational practices applied by the cruise industry to minimise the environmental impacts of their operations. In conclusion technical and operational changes anticipated as a result of current and future regulatory efforts and related developments are overviewed. A brief industry outlook is also presented. The discussion of these various aspects is presented in order to inform the reader of some of the specific actions and developments to date and to provide a better understanding of the overall issues.

The cruise industry is under increasing scrutiny from US Federal Agencies to determine the necessity to legislate in the area of environmental performance for cruise vessels operating in US waters. What is not clearly being understood by certain organisations is the extent of activity currently undertaken by cruise ship companies to control all aspects of waste generation through well-established programs implemented in accordance with existing international mandatory regulations. In order to both complement and facilitate the assessment of environmental impacts and to further pre-empt future legislation in this area Lloyd's Register has developed EP rules (environmental protection rules for the control of operational pollution. These rules provide a prescriptive means to control environmental equipment and systems and establish criteria for performance that far exceed the existing regulatory requirements. Whereas existing specifications concentrate in the area of hardware (MARPOL SOLAS CFRs Class) and the software (ISM ISO 9000 and 14000) on an individual basis the EP rules are designed to verify compliance with stringent environmental performance criteria combining inspection and audit to address all hardware and software issues. The Rules consist of essential core elements and optional more stringent requirements. With the current levels of regulatory scrutiny within the cruise industry the system enables owners to highlight substantial investment in particular aspects of pollution control whilst demonstrating a101380

In sea transportation two-stroke diesel engines and low-grade heavy oil have been used for economy. However some marine engines have been damaged. It is very difficult to clarify why since at present there is no index available to consider combustion characteristics of the general properties of bunker fuel oil without combustion. Furthermore the regulation of sulphur content in the heavy fuel oil now requires the use of low sulphur fuel oil which may lead to a reduction in lubrication. A new constant-volume vessel was been developed (see CIMAC 2004 paper 171). Since then the improvements of the injection part and the preparation of pre-mixed gas have been reported (ISME Tokyo 2005) and very good repeatability of the experiment was carried out. However these were based on only the visualisation results with high-speed photographs. A new OCA (optic combustion analyser) was developed to consider the combustion properties of the bunker fuel oil. The repeatability of the experimental conditions such as history of injection pressure pressure and gas temperature at injection timing was shown to be very good. Photo-sensor high-speed video cameras were used and the pressure in the vessel was measured. Results are presented and discussed and conclusions drawn.

Advances in underwater technology, Ocean Science and offshore engineering. Volume 8. Papers are: EEZ's - a brief sketch of historical developments and current issues, The legal regime and the United Nations Convention on the law of the sea, Mineral resources in exclusive economic zones, Fisheries and other biological resources, Ocean renewable energy resources - a chance for the future?, Modern surveying techniques, The EEZ, the Continental Shelf and modern surveying techniques, Living resources, assessments and quotas, The scale of EEZs with particular reference to areas of US and UK jurisdiction, The development of an integrated marine policy for the EEZ : the case of Japan, The management of an exclusive economic zone : the role of the marine resource atlas, An assessment of the relation of the presentations to exclusive economic zones. The EEZ: opportunities under the legal regime - a summing up, Report from the rapporteur and EEZs in perspective - preliminary impressions of the conference.

The need for monitoring flexible risers is becoming ever more apparent as oil exploration moves to greater depths and wells can be hotter and more sour than experienced so far. In these situations where the limits of pipe design need to be reliably expanded continuous monitoring of pipe health becomes a priority. This paper presents a new advance within the field of optical gas measurement with applications to the monitoring of gases inside the annulus of flexible risers used in the offshore industry. The advance is based on the novel QEPAS (quartz-enhanced photoacoustic spectroscopy) technology. The QEPAS gas sensing technology is introduced and compared to existing gas monitoring and inspection options. QEPAS satisfied the requirements for the detection quantification and monitoring of gas mixtures containing H2S with a precision and accuracy of ( 10 ppm as well as CO2 and CH4 of ( 1000 ppm in flexible risers. The performance of a first prototype sensor consisting of one spectraphone (a module for detecting last-induced sound) consisting of a QTF (quartz tuning fork) or microresonator assembly and two near-infrared telecommunication diode lasers and the associated control electronics are reported. The sensor is capable of monitoring the three target gases simultaneously. Furthermore the next steps towards a commercially available sensor are discussed.

When a clay layer of uniform OCR is subjected to an external load that results in loading of a portion of the clay layer to within the normally consolidated range there exists a boundary within the clay that separates the over-consolidated material from the normally consolidated material. This boundary changes as consolidation progresses. The consolidation of an over-consolidated clay stratum which undergoes a change from an over-consolidated state to a normally consolidated state due to a large increase of load can be modeled using finite difference approach. Two-layers are used to model the over-consolidated state to a normally consolidated states in the clay. A change of soil parameters such as the permeability and coefficient of consolidation between the NC and OC states is also involved. Based on the results of sample computations it is clear that the rate and magnitude of consolidation settlement varies considerably depending upon the magnitude of load and over-consolidation ratio although other consolidation properties such as the coefficients of consolidation and the compression indices are kept unchanged.

The FSA (Formal Safety Assessment) method developed for the systematical (formal) definition and evaluation (assessment) of risks and their elimination or mitigation is described with attention to its historical background basic terminology and the IMO recommended guidelines/stages for its application. A research study in which FSA methodology is used to quantitate the risks to crew environment and owner in the event of failure of a marine 2- stroke diesel main propulsion engine is reported with details of - the scope of the study; the selection of the Suezmax tanker and Capesize bulk carrier (both of which normally use 2-stroke diesel main engines) as suitable ship types on which to base the study; the choice of Sulzer RTA68T-B (single screw propulsion) and RTA48T-B (twin screw propulsion) engines as appropriate for the study; the application of FSA general considerations and costs methodology input data and assumptions risk calculations; risk minimising options notably redundancy measures (including single screw ship conventional maintenance single screw ship reduced maintenance single screw ship with power take in twin screw ship); cost-benefit assessment; and sensitivity criteria. Findings are presented and discussed.

Two Swedish research projects concerning lightweight ship building LASS (Lightweight construction applications at sea) and DIBS (Design basis for fires at sea) jointly conducted large-scale fire tests in December 2007. The tests were also supported by a DNV-led subgroup within the EU-project SAFEDOR. For the experiments a two bed cabin and corridor RoPax replicate surrounded by a properly insulated FRP (Fibre Reinforce Plastic) composite superstructure were built in the SP fire lab in Boras Sweden. All materials used (bedding materials flooring materials etc) except the composite were materials one would expect to find on a standard RoPax vessel. Further was a realistic amount of luggage placed in the cabin. Fire was initiated by igniting a small wood crib placed in the lower left hand side cabin bed. The intensity and duration of the fire that developed when the cabin door was left open and the sprinkler was disconnected was somewhat surprising. The main idea of the project was to design experiments to resemble possible fires in a RoPax cabin. The objectives were to study design fires e.g. fire development and influence of sprinklers ventilation etc and to evaluate the behaviour of a composite structure under realistic fire conditions.

The reliability of main propulsion systems on board ships is essential to ship safety, seaworthiness and the ability of a ship to maintain proper schedules. Recent damage statistics suggest there is a steadily growing number of cases of serious engine and machinery damage due to the poor quality, stability or variations in grade and handling of the marine heavy fuel oil used for these systems. This Guidance has been prepared to help combat the problem: it will serve as a useful reference for ship operation and ship design, and provide fundamental data and information when ISO 8217 is reviewed in the future. Sections cover detrimental elements in fuel oil and diesel engine failures (examples of abnormalities caused by fuel oil), reliability and durability of diesel engines vs marine fuel oil (abnormalities in machinery plants, abnormalities caused by sulphur contents, abnormalities of piston rings and cylinder liners due to catalytic fines, abnormalities due to asphaltene and vanadium, desirable properties of fuel oil), problems related to bunker supplies and receptions and responses (marine heavy fuel oil, bukering for ships in service), problems related to shipboard storage and processing of heavy fuel oil and responses (current state of shipboard fuel oil processing, desirable shipboard fuel oil pre-treatment system, responding to fuel oils not confirming to specifications).

HCCI (homogeneous charge compression ignition) is a mode of combustion in internal combustion engines in which premixed fuel or air mixture is burned spontaneously. This process has great potential to improve fuel consumption and NOx emission reduction. In order to control the heat release rate to acceptable levels the engine must be operated at high dilution levels. This has to be sufficient that the engine can operate essentially unthrottled; the result is a significant reduction in pumping work which leads to fuel economy. In the HCCI combustion process chemical kinetics governs combustion phasing and engine operation but inhomogeneity only has a moderating effect on combustion. Here a single zone zero dimensional thermodynamic model coupled with chemical kinetic equation has been developed using a computer program with MATLAB software to predict combustion characteristics. This model is used to predict the principal parameters of controlling auto ignition optimum combustion phasing and optimum working points. The cycle is simulated with a variety of fuels such as natural gas DME blend of natural gas and DME and PRF (primary reference fuels). To highlight the feasibility of using HCCI engines instead of conventional Diesel engines a standard COP (continuous operation cycle) was investigated and LCC (life cycle cost) and NOx levels are compared.

Environmental consequences due to oil spills are disastrous - like the Prestige catastrophe in 2002. Therefore oil-combating systems must be developed which are capable of operating in rough seas. The design and optimisation of an SOS (seaway independent oil skimming system) are presented. The principle of the system is to separate the wave damping from the skimming process without using moving parts. The system consists of a solid pontoon with a bow segment (inverse ramp) and an integrated collection tank (moon pool). The skimmer glides over the oil polluted water surface smoothing the waves. Subsequently the oil flows beneath the bow segment to an inlet slit where a separation blade guides the oil film into the moon pool. Inside the moon pool a vortex develops behind the bow segment separating the oil from the main flow and transporting it to the free surface of the moon pool where it is pumped off. CFD (computational fluid dynamics) calculations and model tests at different scales (1:9 1:15 and 1:22) with and without oil layer have been carried out. Based on results at different speeds and random seas the geometry of the separation blade and the moon pool are optimized. Oil tests yield an efficiency of the skimming process up to 90 percent in random seas and up to 95 percent in calm water. The assessment of the system includes tests with the skimmer integrated into the carrier vessel MPOSS (multi-purpose oil skimming system).

Deepwater oil and gas fields usually have seabeds of soft sticky clay. A popular strategy for developing deepwater hydrocarbon reserves is the use of steel catenary risers to a floating production vessel both for well production and processed fluid export purposes. Experiments are described which were completed in June 2000 as part of the STRIDE JIP - Steel Risers in Deepwater Environments. These experiments investigated the interaction between a soft clay seabed and a SCR (steel catenary riser). ROV surveys of deepwater SCRs attached to floating production vessels have shown that they can cut deep trenches into the seabed. A set of objectives are identified and to achieve these the seabed end of a deepwater SCR was simulated using a 360-foot long 6-inch diameter steel pipe hung as a catenary across the soft seabed of a tidal harbour. A particular harbour location was found that had seabed properties similar to those of a deepwater Gulf of Mexico seabed. The top end of the pipe string was then actuated with carefully controlled wave and vessel drift motions to simulate a spar platform in 3300-foot water depth. Results are given and discussed and conclusions drawn. Photographs graphs and diagrams appear on pages 6 to 9.

The diffraction theory originally developed for one bottom-mounted vertical circular cylinder is generalised to be applicable to arrays of cylinders such as the columns of a TLP (tension-leg platform). To demonstrate the usability of the present method the wave field and corresponding wave loads for an array of four bottom-mounted vertical cylinders are investigated. The present method provides an approach to analyse ocean engineering structures under extreme (survival) wave conditions. It is known that the frontal wave of tsunami can be described as a solitary wave. The solution strategy employed here uses the Laitone solution of Boussinesq equations to investigate the second order solitary wave interactions with four cylinders arranged in a square shape. The major concern is the transient hydrodynamic forces on each cylinder and the free surface elevation in the vicinity of the structural members. The solution is computed by means using the finite element method. Firstly the governing theoretical background is reviewed. After this the finite element procedure applied to the governing differential equations is briefly described. Investigations employing the numerical model include the interaction of a second order solitary wave with an array of four cylinders. The wave field and hydrodynamic forces are then analysed for different angles of incidence.

ARTICLES Broeze, Frank. “The Political Economy of a Port City in Distress: Hamburg and National Socialism, 1933-1939” XIV, 2, 1-42 Laurent, Jerome K. “‘And Cut Throat Competition Prevented:’ Concentration and Control in Great Lakes Transportation, 1915-1940” XIV, 2, 43-84 Butcher, John G. “Getting into Trouble: The Diaspora of Thai Trawlers, 1965-2002” XIV, 2, 85-121 Hahn-Pedersen, Morten. “Local Entrepreneurship in the Danish Offshore Industry: A Case Study on Henning Kruse and Esbjerg Oilfield Services Ltd.” XIV, 2, 123-143 Moring, Beatrice. “Nordic Coastal Communities in Historical Perspective: The Interaction of Economic Activity and the Household” XIV, 2, 145-165 Vanfraechem, Stephan. “The Antwerp Docker between Militantism and Pragmatism, 1900-1972” XIV, 2, 167-180 Walenciak, Agnieszka and Roe, Michael. “The Development of the UK-Poland Liner Shipping Trade between 1919 and 1989” XIV, 2 181-206 RESEARCH NOTES Khiun, Liew Kai. “Of Lives, Lungs and Limbs: Workers at Sea and Onshore in the Twentieth Century” XIV, 2, 207-224 Tripati, Sila; Gaur, A.S.; Sundaresh; and Bandodker, S.N. “Marine Archaeological Explorations Off Goa, India” XIV, 2, 225-245 FORUM: NEW APPROACHES IN NORDIC MARITIME HISTORY Dalsgaard, Søren. “Maritime History: The Case for Further Contextualisation” XIV, 2, 272-283 Holm, Poul. “Introduction” XIV, 2, 247-248 Nielssen, Alf Ragnar. “Small Coastal Communities in Northern Scandinavia and their Environmental Adaptation” XIV, 2 265-271 Poulsen, Bo. “The Renaissance Sea: Perceptions in Danish and Norwegian Topography” XIV, 2, 284-292 Rheinheimer, Martin. “Biographical Research and Maritime History” XIV, 2, 249-264

Int conf held in Hamburg in 1978 Papers are Oil recovery system for open sea use - the springsweep system Prevention and abatement of oil pollution Current US coast guard technological developments relative to the detection control and clean up of oil spills Swedish philosophy and technical solutions for combating oil spills at sea Practical experience of oil spill clean up with reference to recent major incidents Application of oil spills dispersants by aircraft Oil spills US government policy and cooperation with the American society for testing and materials Methods of recuperating and storing oils accidentally spilled on water Application of an oil spilled compuyrt model to Narragansett Bay and Thode Island Sound SEA trials of the One Hundred Ton oil recovery vessel for Bantry Bay Oil spills chemicals - when where how An international oil spill contractor Hyde oil/water separation systems - a new approach to binary non miscible liquid separation Practical experience of using petroleum products in the fight against marine pollution Possible methods of identification of oil spills The development of oil Mops dynamic skimmer The use and selection of sorbents in oil spill clean up Oil content monitoring in ships bilge and ballast water discharges and eliminating measurement errors caused by suspended solids Identification of ships responsible for oil releases by means of oil residue tagging

TNO developed a prototype NEEBA (net environmental - economic benefit model) that can assist in choosing the optimal response option in a particular oil spill scenario. Five response options are considered. Several spill scenarios have been worked through with the TNO NEEBA model. The response option 'shore line clean-up' (let the oil wash ashore) is one option in the case of heavy viscous oils. Two concepts are introduced with respect to 'shore line clean-up': moving a damaged vessel closer to the shore so that should the heavy fuel oil be released and beach it will impact a shorter length of coastline; and if heavy oil is spilled offshore it may be better not to take the more expensive and or ineffective options of trying to recover or treat it at sea but rather let it come ashore where it can be dealt with in a more cost-effective manner. It is concluded that to optimise this response option one should try to let the oil wash ashore under controlled conditions. This is possible in cases where a damaged tanker still containing heavy oil is involved. Such a damaged tanker should be brought as close as possible to the coastline in order to concentrate the oil spill on the coastline. This option requires preparation in the form of coastal sensitivity mapping. Secondly permission needs to be obtained from a municipality to bring a leaking tanker closer to their coast line.