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The past 25 years has been marked by the introduction of marine environmental regulations that have had a profound effect on how ships are designed built and operated. Ships being designed and built today must accommodate not only current regulations but anticipate future ones over their 30- to 50-year life cycles. The US Chief of Naval Operations Office of Environmental Safety and Health (CNO N45) has articulated a vision for the Environmentally Sound Warship of the 21st Century. This vision incorporates the 'Sense of Congress' for a naval ship designed to operate in full compliance with environmental regulations worldwide. The task of the Navy engineering team is to translate this vision into reality; a ship capable of prevailing in time of war and able to carry out operations in all areas of the globe unencumbered by special procedures for environmental compliance. The key to this warship design is the early integration of environmentally sound principles materials and processes into the ship acquisition process; minimisation of both hazardous materials and generation of post shipboard consumer waste during operation; adaptation of integrated systems to reduce the volume of wastes and enhance processing efficiency; reduced manpower requirements; and crew indoctrination in environmental protection.

Automated pilot aids such as closed-loop systems to control position are becoming a relatively common and popular addition to ROVs especially for operation near the seafloor. Systems have been fielded that enable station-keeping and precise motion control using a variety of different sensors including acoustic arrays (e.g. LBL (long baseline sonar) DVLs (Doppler velocity logs) and vision. These systems not only reduce the workload of the ROV pilot they also improve the pilot's awareness of the ROV's position in the work area. Automated positioning is less common in the midwater than near the seafloor where there is a reference for accurate position information. A method is described for fusing an inertial position measurement from an USBL (ultra-short baseline) sonar with a water-relative velocity measurement (from DVL ACM or other device) to improve knowledge of an underwater vehicle's inertial position. The goal is accuracy sufficient to enable closed-loop position control in the midwater. The implementation of a kinematic estimator which computes vehicle inertial position and water current velocity is described. Details of this estimator are presented as well as results of field trials which demonstrate the viability of the technique. Field experiments show improvements in accuracy on the order of a factor of 5 above the USBL's raw measurements.

The effect of following seas on the added resistance of the PACT base America's Cup hull is presented. A 1:8 scale model of an International America's Cup Class yacht was refinished to its original lines as the PACT base hull (canoe body with no appendages). Using this hull model tests were carried out in the following seas condition. With the model fixed in surge upright resistance tests were carried out for one speed inn both smooth water and regular waves. The model was free to heave and pitch while restraining all other degrees of freedom. The data analysis reveals that at wavelengths approximately greater than two model lengths the added resistance of the model is negative. A negative added resistance implies that the average drag force of the model is greater than the still water resistance. Furthermore the form of the data suggests that in waves longer than was tested in this experiment the added resistance of the model may converge to the still-water resistance. The experiment also verifies that the added resistance is proportional to the square of the wave height. The pitch and heave motion characteristics of the model as expressed in the form of response amplitude operators are independent of wave slope. This is to say that for a particular motion the response amplitude operators for each wave slope overlap one another. Conclusions are drawn and recommendations for further work are identified.

The book presents 31 chapters, 733 illustrations, a classification of the 16 catching methods and the most extensive bibliography on the subject of fishing. Contents include: Chapter one. Catching methods in fisheries; an introduction. Chapter two. Fishing by gathering. Chapter three. Male and female divers. Chapter four. Animals as a help in fisheries. Chapter five. Fish harvesting after stupefying. . Chapter six. Spearing, harpooning and shooting fish. Chapter seven. Fishing with clamps, tongs, rakes and wrenching gear. Chapter eight. Line fishing: basic implements. Chapter nine. Line fishing: gear and methods. Chapter ten. Fishing for sport and recreation. Chapter eleven. Attracting, concentrating and frightening fish. Chapter twelve. Pole-hooks and rippers. Chapter thirteen. Natural and artificial shelters. Chapter fourteen. Mechanical fishing gear: traps, lines and snares. Chapter fifteen. Permanent and temporary barriers. Chapter sixteen. Trapping. . Chapter seventeen. Fishing in the air. Chapter eighteen. The art of net-making. Chapter nineteen. From the scoop basket to the stow net. Chapter twenty. Dredges and beamtrawls. Chapter twenty one. Fishing with bottom trawls. Chapter twenty two. Trawl fishery in three dimensions. Chapter twenty three. Gods, fishing, and the captain’s nose. Chapter twenty four. Seining in fresh and sea water. Chapter twenty five. Ish shoals and surrounding nets. Chapter twenty six. The drive-in fishery. Chapter twenty seven. Liftnets and fish wheels. Chapter twenty eight. Cover pots and cast nets. Chapter twenty nine. Gillnetting. Chapter thirty. Entangling nets. Chapter thirty one. Fishing effects and harvesting machines. Appendix . Classification of catching methods. A.1 Principles of classification. A.2 Main groups of catching methods. A.3 Revised classification. Bibliography. Subject index. Species and product index. Geographical index.

Since the first book was published in 2006, resilience engineering has consistently argued that safety is more than the absence of failures. Several book chapters and papers have illustrated the advantage in going behind 'human error' and beyond the failure concept, and various complicated accidents have accentuated the need for it. But there has not yet been a comprehensive method for doing so; the Functional Resonance Analysis Method (FRAM) fulfils that need. Whereas commonly used methods explain events by interpreting them in terms of an already existing model, the FRAM is used to produce a model of what is needed for everyday performance to go right. This can then be applied to explain specific events, by showing how functions can be coupled and how the variability of everyday performance sometimes may produce unexpected and out-of-scale outcomes - either good or bad. The FRAM is based on four principles: equivalence of failures and successes, approximate adjustments, emergence, and functional resonance. Since the FRAM is a method rather than a model, it makes no assumptions about how the system under investigation is structured or organised, nor about possible causes and cause-effect relations. Instead of looking for specific failures and malfunctions, the FRAM explains outcomes in terms of functional coupling and resonance. This book presents a detailed and tested method that can be used to model how complex and dynamic socio-technical systems work, and understand both why things sometimes go wrong but also why they normally succeed.

The impending introduction of international legislation against single hulled tankers (IMO MARPOL Annex I regulations 13G and 13H) is driving commercial tanker operators to replace much of the older tanker and product tanker fleets with new construction double-hull vessels. While there is little fundamental change in the basic modern products tanker design from its predecessors some of these new tankers are also including other design features to minimise hazards that may lead to environmental accidents and while improving operating efficiency and costs. The pressure to adopt the commercial regulations for naval tankers is increasing in many countries as the potential negative publicity associated with an oil spill from a naval vessel would be significant. The longer life of the naval tanker and the extended procurement timescales compared to the short-lived commercial tanker is also leading to the adoption of innovation in tanker design being driven by the commercial sector. A family of affordable naval replenishment vessels is discussed that have been developed by a joint design team drawn from commercial Norwegian ship designers Skipskonsulent and UK-based naval designers BMT Defence Services. This family of designs draws on the wide experience of the two companies offering the pull-through of the best commercial tanker design practice into the naval environment. This family of ships is scalable in size and capability through careful design of systems allowing capability growth. 90991 The future of Australia's maritime industry

This paper highlights the challenges associated with the development of a hypothetical subsea oil prospect in deepwater Gulf of Mexico. This hypothetical development scenario comprises two subsea wells in 5800 ft of water with tieback distances of approximately 40 miles to the nearest host facility and estimated shut-in tubing pressures in excess of 10000 psig. Using traditional dual pipe-in-pipe insulated flow lines for flow assurance management would not be an economical approach for such a small development. A more conventional surface-piercing facility in the field would be technically feasible but it would require much greater hydrocarbon reserves to make it cost-effective. To address the cost and flow assurance challenges a development scenario was then proposed which comprised a single heated insulated flow line a subsea multiphase flow meter for each well and a subsea “high-integrity pipeline protection system” (HIPPS) to avoid the need for thick-walled flow lines. The technical and economical feasibilities of the proposed development scenario were studied and operational challenges addressed. This paper presents the proposed subsea field architecture as well as a summary of the study results including flow assurance considerations field layout CAPEX estimates and a discussion on operational issues. Finally the authors propose recommendations for further studies as well as possible system design optimizations.

The Kraft recovery boiler is a steam boiler used to recover process chemicals and to generate steam for paper-making and electricity generation. The fuel is spent liquor from the digester and contains dissolved organics. Hot corrosion can occur on the cold-side of air-ports in Kraft recovery boilers. The primary corrosion mechanism involves the migration of sodium hydroxide and potassium hydroxide vapours through leaks in the furnace wall at the air-ports and their subsequent condensation. It has been reported that stainless steel is attacked much faster than carbon steel in composite tubes and that carbon steel tubing when used with a low-chromium refactory does not exhibit this type of corrosion. For hot corrosion fluxing of metal oxides either acidic or basic fluxing takes place with a solubility minimum at the basicity of transition between the two reactions. For stainless steel if the basicity of the fused salt is between the iron and chromium oxide solubility minima then a synergistic effect can occur that leads to rapid corrosion. The products of one reaction are the reactants of the other which eliminates the needs of rate-controlling diffusion. This effect can explain why stainless steel is attacked more readily tan carbon steel. Experimental procedures are described and results are presented and discussed.

In 2001-2002 KBB launched the HPR range of radial turbine type turbochargers for medium-speed 4-stroke diesel and gas engines in the power range of approx. 500 - 3000 kW. Examples of successful series usage are described. Altogether over 30 engine models are running with more than 100 turbocharger variants of HPR type. A whole range of further developments has been introduced over the last few years in order to improve the reliability of turbochargers in the field. A special coating for radial turbine nozzle rings has been developed and the washing process for turbine cleaning has been optimised both of which prolong the lifetime of the turbochargers in HFO (heavy fuel oil) operation. The bearing system was modified for applications under higher exhaust gas and oil temperatures which considerably enhances durability especially in gas engine applications. Turbo-charging of modern diesel engines still places particularly high demands on the compressor design. The first generation of the HPR compressors (series A) was designed for a pressure ratio of 4.2 at 100% engine load. The following years revealed a rapid increase in engine-related requirements concerning charge air pressure and efficiency of the turbochargers.

NAVOCEANO (the Naval Oceanographic Office) is a naval activity whose primary purpose is the collection and processing of data relating to the physical properties of the Earth's oceans. Inherent in this is a requirement to collect store process and archive massive quantities of data. NAVOCEANO has mission applications in numerous scientific disciplines including hydrography bathymetry physical oceanography acoustics and geophysics. NAVOCEANO uses eight oceanographic survey vessels to support this mission including the current-generation T-AGS 60 multidisciplinary platforms. Also the NAVOCEANO obtains oceanographic data from airborne data collection drifting buoys and remote sensing. NAVOCEANO participates in international co-operative survey agreements with foreign countries providing an additional valuable data source. The net effect is a voluminous growth in data to be processed stored and archived. The requirement to move in-process data files in the range of hundreds of gigabytes between workstations and servers has taxed the capabilities of the NAVOCEANO Local Area Network to its limit. The restructuring of the NAVOCEANO information technology enterprise to meet the growth challenges that began in the late 1990s and are expected to continue over the next several years is described. A fundamentally different architecture is described that meets the processing and data storage-movement needs of the typical NAVOCEANO user while reducing the strain on the NAVOCEANO backbone. In particular the definition and implementation of a SAN (storage area network) is discussX19535

This is a case study of using GP (genetic programming) on the acoustic backscatter data processing for the classification of different epi-benthos. The purpose is the provision of an improved classification capability that will bring a more reliable understanding of the acoustic backscatter characteristics of different habitats. The result of this study proved that the acoustic classification capability for the recognition of different seafloor habitats can be enhanced by the adoption of GP in the data processing. With a suitable fitness criterion GP provided an automatic and alternative option to evolve from several initial candidate features into a final compound feature with improved classification performance. Different designs of initial candidate features were also tested to assess the final feature's performance. The execution of GP is illustrated by giving an example of data collected from different seafloor habitats in the Australian coastal waters. The comparison of the classification performance between the present results and those from a previous study without GP is provided. The conclusion is that the implementation of GP in the acoustic data processing can enhance the acoustic classification capability for the characterisation of different seafloor conditions.

The isoengine is a new high-efficiency reciprocating engine in which compression and combustion are carried out in different cylinders. The compression is carried out quasi-isothermally by injecting a large amount of water into the cylinder to cool the air. The water is not evaporated but separated from the compressed air cooled and then re-injected. This approach reduces compression work and allows a high degree of recuperative combustion air preheating. The fuel is burned at approximately constant pressure determined by the pressure of the supplied hot compressed air. A 3 MW prototype isoengine was built and some initial test data were obtained. A partnership agreement ensured its continued testing and development. At present the prototype engine is in the process of re-construction. The first prototype isoengine is described together with some of the technical issues which have arisen during the development so far. Early testing has shown isothermal compression at 410 rpm. The firing of the combustors at low power levels has also been shown. Future testing will focus on the increase of speed and power to the design levels. Computer analysis is being used to interpret the test results and to guide the direction of future isoengine designs. A computer model which is used for this purpose is described and calculations of this model are compared to some of the test data. The paper describes parametric studies for a future engine. These calculations show that it is preferable to limit thermal loading by reducing the fuelling101033

Verification of large ship sub-structures such as double-bottom under severe loads requires a tool for system analysis. At this scale the elastoplastic analyses based on FEM (finite element method) would require too much effort and time despite the rapid development in the computer technology. ISUM (the idealised structural unit method) was proposed in 1984. Its key concept (to divide the structure into as large elements as possible keeping the main features of the non-linear structural members behaviours in their formulation) was afterwards used in the development of various types of plate elements. The common aim was to develop elements significantly larger than in FEM therefore to obtain a drastic reduction in the calculation time. An application of ISUM to analyse collapse behaviour of large ship structural modules is developed. The system analysis of double bottom structure as well as isolated floor and girder models is achieved with models consisting of large plate elements and beam-column elements for the inner and outer bottom plating and Timoshenko-beam elements for the girder web plates. Fundamental collapse modes and localised failures in double-bottom structure under pressure loads are obtained in a very short time compared to FEM. Local collapse of rectangular plate panels under transverse thrust rapidly spreads from the central area of the double-bottom towards the sides and stool supports but the structure exhibits considerable reserve strength in the overall bending.

The Detroit District of the Army Corps of Engineers (Corps) is responsible for 26 US Great Lake harbours with parallel jetty entrances. These jetties many in operation for over 100 years were typically constructed of rock-filled timber cribs. Over time the timber cribs have deteriorated and have been or need to be replaced. The typical rehabilitation approach has been to drive steel sheet pile around the existing structure and to place a concrete cap on top thereby encasing the original structure. However after rehabilitation there was a perception of increased wave heights in the channel. This is apparently due to the fact that the timber crib jetties were rough porous structures especially in their deteriorated state and were much more effective at dissipating wave energy than the new sheet pile jetties. To remediate the more energetic wave climate the Corps removed short (250 ft) sections of sheet piling at selected harbours and replaced them with pocket wave absorbers. A pocket wave absorber is created when a section of a sheet pile wall is recessed from the remainder of the jetty wall. Stone is then placed in the pocket to provide a rough porous sloping surface that is intended to dissipate wave energy. The main aims of this study were to determine the effectiveness of the existing structures and to help set guidelines for the construction of any future pocket wave absorbers. Laboratory field

A typical marine drilling riser joint has a main riser pipe in the middle as the load carrying structural member; the auxiliary lines are outside of the main riser pipe and piercing through the synthetic foam module. Whether the auxiliary lines carrying any tension load depends on the float between the auxiliary line's couple housing and the cut-out 'pocket' in the flange has closed or not. The advantage of a load-sharing flange design is the main riser pipe wall thickness reduction. As a result less riser tension is required; hence less deck load. A significant cost can be saved in the drilling vessel construction. For a load sharing marine drilling riser the main riser pipe carrying the full tension load (the first slope) then auxiliary lines sharing the load (the second slope) is well accepted and used in the design. Therefore in the finite element analysis for a load sharing marine drilling riser flange the two-slope theory is followed. However a much more elaborate model reveals that the main riser pipe has a third slope when the auxiliary lines are pressurised. Marine drilling riser using a load sharing flange design as the coupling connector is becoming popular as people venture into the ultra deep water over 10000 ft. The advantage and goal is the reduction in riser pipe wall thickness; hence the riser system weight saving. The float (gap) value between the auxiliary lines' coupling and the flange cut-out pocket is diligently designed in the engineering phase and carefully maintained in the manufacturing phase so that auxiliary lines start sharing the load at the desired tension magnitude.

Dynamic response analysis of ship propulsion systems has become an accepted and proven practice worldwide as part of the ship propulsion system design process. This process entails the use of a simulation model of the hull and integrated propulsion machinery components mated with a model of the propulsion Machinery Control System (MCS) algorithms. From this entire propulsion system model extensive simulation tests are performed to predict the systems steady state operating envelope as well as its transient performance for various drive modes hull displacements and environmental conditions. Tests are also performed to predict the propulsion system's dynamic response for various manoeuvres. The analysis of these simulation results is an integral part of the design process because it allows system performance estimates to be available during the design stage of the ship. The analysis is essential in designing and validating MCS algorithms and contributes substantially to the development of training/test support systems. In essence it provides an understanding of how the propulsion system and propulsion control algorithms will function on the ship before it is built. Sail it before you build it. This paper describes the use of dynamic response analysis in the MCS algorithm development process and includes examples and lessons learned during the application of this process to various marine applications.

Due to the increasing power of electric power and propulsion systems on board warships the magnetic signature generated by these systems has become a significant design aspect because of mine threats. In the conceptual design phase of a ship it is important to have a rough idea of its expected magnetic signature. The aim of this work is to obtain a practical too that predicts these magnetic fields. The aim here is to develop this model for the magnetic signature of a ship generated by the electrical power and propulsion system. An outline of the strategy to achieve this is given as well as the results obtained so far. Firstly it is argued that the Maxwell equations can be reduced to a subset describing the magneto stationary problem. In the paragraph 'basic geometry' a simple configuration is considered that can be seen as a primitive form of the problem at hand. This configuration brings to light the fundamental properties of the modelling problem and can be used as a reference to put the different modelling tasks in perspective. After the outline of the modelling strategy those elements of the modelling that have been completed so far are considered. Finally the results are evaluated and future work is identified.

With increasing fuel prices and the demand to achieve lower emissions gas engines have become a real seller on the engine market. Various new engine types entering the market show that the development in terms of power density and efficiency has not yet come to an end. The piston as a core engine component is directly affected with higher peak firing pressures and higher temperature loads. Thus new ways need to be found to ensure proper functionality at higher demands. Various challenges impact upon the piston design of large bore gas engines. Market and customer demands for increased engine efficiency and stringent exhaust gas legislation need to be met with measures like employment of the Miller Cycle and others. This consequently results in higher peak cylinder pressures. At the same time temperature spots need to be avoided in order to stay away from knocking combustion. All these affect the piston and are essential for gas engines with spark ignition (pre chamber or open chamber) as well as for dual fuel gas engines. In close co-operation with the engine builders MAHLE developed new piston designs addressing the above requirements. Here measures to reduce the maximum piston temperature by approx. 25K through cooling optimization are explained. FEA results of temperature calculations are compared with measured temperatures showing the high capability of the FEA simulation.

A method of marine seafloor classification is proposed which promises to be a useful and simple tool for characterising bottom and sediment types. The distribution of sediment types is surveyed using Datasonics SIS1502 sidescan sonar interfaced to GeoDAS (Geographical Data Acquisition System). The GIS (Geographic Information Systems) software ERmapper is used to classify the digital sidescan image based on colour differences using an unsupervised classification technique. Sediment samples are taken from the study area and are analysed for grain size distribution to verify the use of ERmapper as a classification tool. The imagery clearly reveals different sediment properties. These differences are also distinguished by the unsupervised classification process. An insufficient number of sediment samples is processed to allow for a statistical comparison of sediment grain size distribution and the sidescan image. However the sediment size distribution observed in the samples analysed shows a clear relationship to the sidescan image. This analysis therefore shows that the use of sidescan sonar coupled with GIS software has the potential to be used to remotely characterise sediment types within the coastal zone.

This paper describes the US Navy's program to ensure that compensated fuel-ballast ships comply with oil waste discharge requirements during refuelling and that the operational capability of these vessels is optimised by the reduction-elimination of water hideout. The CFD (computational fluid dynamics) analysis is described together with 1/8-scale physical model experimental efforts to assess the performance of the Arleigh Burke (DDG 51) class of US Navy guided missile destroyer mid-group compensated fuel-ballast tank 5-300-2-F. Results show that baseline configurations can have mass fuel discharge before refuelling is terminated due to non-uniformities in tank filling. The tanks also have a high potential for fuel- water mixing particularly where buoyant jets impinge on the tank top. Various modifications to the tank structure and diffuser piping are assessed. Results show that water hideout and problems with mass fuel discharge can be minimised or eliminated with relatively minor modifications to the structure. Also the potential for fuel-water mixing can be reduced by eliminating buoyant jets. The ultimate objective of this work is to quantify effluent fuel concentrations during refuelling.