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In a marine disaster scenario the goal of SAR (search-and-rescue) is to search for and find life rafts and rescue victims as efficiently and safely as possible. A practical robotics approach to this scenario is the use of a team of fast autonomous UAVs together with a team of autonomous helicopters with rescuers onboard. In addition if the UAVs can circle around the found life rafts to provide high beam light and environmental information to the rescue helicopter while rescuers are retrieving victims the efficiency and safety of the rescue operation will also improve significantly. A co-ordinated control technique is presented that allows teams of UAVs (unmanned aerial vehicles) and manned rescue helicopters to search autonomously for and track multiple life rafts in a marine disaster scenario. A sensor model and an objective function are first proposed to stochastically enable co-ordinated search within the recursive Bayesian filter framework. Once a life raft has been found a UAV and a helicopter co-operatively rescue victims on the life raft. Numerical results first show the superiority of the proposed technique to the conventional marine search techniques. The proposed technique is then applied to a practical marine SAR scenario where heterogeneous vehicles are co-ordinated to search for and track multiple targets. The result shows the applicability of the technique to various real world scenarios. Firstly the recursive Bayesian filtering is reviewed. This preX25037 Autonomous control system (SPARCS) for low-cost subsea production systems

UUV (unmanned underwater vehicles) have been used to explore physical areas where humans are unable to go such as a deep dangerous and unpredictable ocean environments. However a single UUV is usually large and expensive to run and can only cover a limited area on any single mission. A team (or 'swarm') of low-cost vehicles could cover an area quickly. There are significant problems with co-operative underwater vehicles. In order to solve these problems lessons may be learned from animal group behaviour. Study of cooperative biological teams may lead to a short cut in the development of engineering systems and may offer distinct advantages over traditional control methods. A behaviour-based approach is presented with fuzzy logic priority weights to investigate the feasibility of a team of UUVs. It is concluded that this algorithm is a possible solution for multi-UUVs cooperation mission. From simple scenario simulation the results show that the different parameters have significant effect for mission implementation. The results may give a clue to minimise the trajectory of a mission and decrease the energy consumption which is always desirable in UUV deployment. From the results it can be concluded that the approach has potential for a real team of co-operative UUVs.

Increased exploration and use of ocean resources has led to an increased demand for a variety of structures such as offshore mobile drill rigs tension rigs TLPs (tension leg platforms) guyed towers and gravity structures. Such structures are subject to wind loading along with wave forces with substantial pullout forces. To resist uplift forces of great magnitude massive foundations are required. An economical and competitive alternative to these massive foundations is a lightweight foundation provided by anchors. These anchors are structural elements that can be in a variety of forms. However very little is known in a quantitative sense about the response of anchors embedded in submerged sand to the rate of loading in pull out. The influence of rate of pull on the uplift performance of circular anchors embedded in submerged sand at two densities is investigated in laboratory model tests of fairly large size. Pullout resistance increases with the depth of embedment and rate of pull. The recorded pore water pressures are negative irrespective of rate of pull. The magnitude of negative pore water pressure in the snap loading is higher than the slow loading for identical test conditions. However this effect decreases with depth of embedment. Higher pullout resistance in snap loading is attributed to dilatancy and negative pore pressure and the peak pullout load has been found to be two times that of slow rate of pull for an embedment ratio of 1:3 in dense sand.

Two of the most important structural configurations made of composite materials are plate and shell type structures. They are laminated of many plies or layers. Usually the composite structural panels are in the form of single skin laminates reinforced as necessary by stiffeners in order to achieve the economy in weight in the process without reduction of strength or the critical buckling load. Depending upon the behaviour under torsion the stiffener can be classified into two categories: open and closed sections. The open section such as the 'I' inverted 'T' 'Z' 'J' and rectangular sections are torsionally flexible against the closed section in the form of hat and box sections. In metallic and FRP construction of aircrafts and ships the curved section stiffeners have so far been disposed in various ways within the structure. The positioning of the stiffeners with respect to the shell midsurface i.e. eccentric or concentric is also a matter of concern to the structural analyst. When the stiffener centroid is coincident with the plate-shell mid-surface it is called concentric stiffener whereas the stiffener centroid and plate-shell mid-surface is eccentric it is called eccentric stiffener. Here emphasis is placed on the use of eccentric-concentric open-closed section laminated stiffeners in laminated shell structures under various loading and boundary conditions. Finite element buckling analysis is presented of laminated hat stiffened shallow and deep shells using arbitrarily oriented stiffener formulaX38137

The Corps of Engineers has long recognised the need for effective coastal sand management but steps have only recently been taken to effectively address the issue. Man-made harbour and coastal structures built over the past 150 years have led to the rapid development of major cities along the shoreline. However many of these projects while performing their intended function have adversely affected not only the adjacent shoreline but downdrift as well by altering the natural littoral processes. Unfortunately the Buffalo District has a number of large Federal and non-Federal projects that have adversely impacted the coastal zone and coastal processes. Numerous studies have been carried out to study the impacts of these projects however mitigation of these impacts has been virtually non-existent. Recently new programmes and policies have emerged to address this problem and are gaining strong support. The renewed emphasis on these programmes is due in part to a change in philosophy concerning the coastal zone and coastal sediments. The coastal shoreline and coastal sediments are now viewed as valuable natural resources with benefits that extend beyond the present navigation and recreational uses. Several examples of studies that address sand-sediment management are addressed. Shoreline processes are considered as well as impacts of shoreline and navigation structures clean dredged sand and sand management programs.

In 1997 the US Army Corps of Engineers (Detroit) began a long-term assessment of potential shoreline flood-erosion damages along Lake Michigan over the next 50 years due to fluctuating lake levels. This study LMPDS (the Lake Michigan Potential Damages Study) is dedicated to meeting several of the recommendations that emerged from the 1986-1993 IJC (International Joint Commission) Great Lakes Levels Reference Study in particular to 'objectively assess the economic value of all shoreline interests in terms of potential damages that could occur under differing hydrologic conditions or alternate management approaches to lake level controls'. In 1998 the US Army Corps of Engineers (Buffalo) began the Lower Great Lakes Erosion Study with the key first-year objective of developing shoreline classification recession rate land use and land use trend databases for the US shorelines of Lake Ontario and Lake Erie. These databases are to be the foundation for a lake-wide shoreline erosion modelling system anticipating future shoreline erosion potential based on given future climate and water level scenarios. The system may ultimately be used to address issues related to lake level control CZM (coastal zone management) and site-specific designs.

Flexible risers are composite structures which are used in the retrieval of offshore oil and gas reserves. Flexible riser cross sections are typically constructed from concentric layers of steel polymer and insulation. Both bonded and unbonded constructions are commonplace with unbonded layers providing greater levels of compliance. Flexible riser systems are increasingly being used in ultra deepwater environments. In these harsh environments the riser can be subject to new extremes of dynamic loading. As a result the dynamic bending response of the riser becomes a critical factor in the riser design. Non-bonded flexible-pipe risers provide a structurally compliant solution in offshore floating production systems for the recovery of oil and gas. The bending stiffness of the flexible pipe is an important property in designing the riser system to safely withstand extreme and fatigue loading conditions. These risers have two fundamentally different bending stiffness properties that depend on whether the riser system is pressurised or depressurised. A depressurised riser has a comparatively small linear bending stiffness. Most riser designs apply this stiffness as its produces conservative (large) bending responses. In recent years the bending response predicted from the depressurised bending stiffness has proven overly conservative and there has been an increasing demand to consider the larger hysteretic bending stiffness of the pressurised riser.

This book provides engineers and management with the economic background necessary to insure that technically feasible engineering projects will also be economically attractive business ventures. The author presents the basic tools of economic analysis necessary for evaluating engineering-based investment proposals. He shows how basic economic principles are applied to the analysis of engineering project to make possible the soundest management decisions, and how the failure to follow these principles can lead to costly, misleading, and sometimes financially disastrous results. The book is divided into 15 chapters. The first two chapters present background of engineering economic analysis, covering feasibility studies and reports and time value of money. The next three chapters cover the different approaches to investment analysis and methods of measuring investment performance. The following give chapters deal with different kinds of costs and how they can be handled. Included are depreciation, the cost of capital, estimation of capital and operating costs, and equivalent annual costs. The next two chapters cover breakeven and profit analysis. Special attention is paid to the effect of variables such as overhead costs, markups, and sales volume on the breakeven and profit structure. In the final three chapters the author discusses special techniques such as economic forecasting, risk evaluation, and profitability modelling. Here everything from the earlier chapters – markets, prices, costs, capital requirements – is brought together into cash flow and profitability models that accurately describe the overall economic environment and conditions under which a company can expect to operate.

This book is intended for all who are concerned with design and production, particularly in engineering establishments. As the title does not fully explain the contents, some information is provided here to encourage the reader to proceed. This investigation into a hitherto unexplored aspect of production design elements, and the relative cost of the use of unnecessarily fine tolerances, was initiated by the Ministry of Defence Naval Weapons Manufacturing Techniques Committee (of which the author was a member) in an attempt to provide accurate data representing the relative cost of gears of Class 1, Class 2 and commercial accuracy. It was soon realised, however, that the accuracy of gears depended on factors other than those associated directly with cutting the teeth. The methods employed to produce the gear blank, and the mounting bores in the structures which would support the gears in service, were among the factors that had to be taken into account. It was obvious that a new approach was required. Any end result, to be of real assistance to designers, would have to include data covering the whole field of engineering production. These data, it was realised, must be available to the designer at the initial design stage, in readily used form, to avoid unnecessarily high cost of production, and sometimes failure to produce to the required accuracy with the available plant. This book shows how the provision of comparatively simple data can achieve the desired result.

Sonsub is currently operating an industry standardized new generation Completion/Workover Riser System (C/WO Riser System). The riser is based upon a unique concentric design with a 4 inch nominal production bore and a 2 inch equivalent annular flow area and is rated for 10000 psi working pressure. The system includes all of the equipment required for use in well completion operations to run and install the tubing hanger and subsea tree and during workover operations to provide wireline and/or coiled tubing access into both the production and annulus bores. The system is currently being used in around 2100 feet of water to complete two wells in the Gulf of Mexico. The operation of the system promises to be very cost effective due to shortened running times and easier handling and maintenance aspects. Based on the riser technology a new slender well drilling riser system has been developed which will be used initially in deepwater exploratory drilling programs but is eventually planned for use in deepwater production applications. It provides the same capabilities as a conventional drilling riser but offers significant advantages in terms of reduced size and weight increased operating envelopes and reduced costs.

The focus of the offshore industry is moving increasingly towards deepwater and therefore attention is concentrated on life-cycle development costs such as development lead times equipment standardisation use of resources. The metocean challenge is to reduce costs while maintaining adequate safety levels. The metocean (meteorological and oceanographic) issues and challenges associated with this move towards deepwater exploration and field development are examined. A brief review is given of deepwater prospects and developments worldwide and some of the deepwater concepts being applied or considered. A comparison is made between the relative metocean conditions that need to be designed for and considered when estimating potential workability. The relative contribution of waves current and wind to overall loading is examined in particular for tropical areas experiencing strong currents. It is defined where metocean fits into the overall process of deepwater development and key drivers are identified. Some of the specific metocean challenges relating to deepwater are discussed considering such issues as shelf edge currents current profiles seasonal and annual variability in conditions as well as the El Nino and the North Atlantic Oscillation climate indicators. Finally these issues are linked with the overall requirements for metocean information at each stage in the field development process - from initial concession evaluation right through the process to field abandonment. The recent trend to begin metocean data collection in deepwater areas much earlier in the process than previously (frequently in advance ofX44235 Deepwater development and high impact technologies for marginal fields

In the Netherlands operational processing of SeaWiFS imagery has resulted in a time-series of images of TSM (total suspended matter concentration) in the North Sea for 1999 and 2000. The TSM algorithm used provides reliable results for this case II water which is dominated by sediment from various sources. However the algorithm can seriously overestimate TSM concentrations in areas with high reflectance values due to algal blooms and therefore blooms may be misinterpreted for areas with predominantly high sediment concentrations. In individual images experts can easily recognise algal blooms. However for operational monitoring a more reproducible and objective method is necessary. Results are presented from a study to design a method that discriminates between areas where high reflectance values are mainly due to high concentrations of suspended sediments and areas where high reflectance values are due to algal blooms. The method is described. It is based on maximum likelihood classification of three spectral band combinations where the classes are established by selecting characteristic regions of interest in several SeaWiFS reflectance images (the training set). The method is applied favourably to the training set for consistency and to a test set of other images where algal blooms are known to be present.

Improving the performance of modular low-cost AUVs (autonomous underwater vehicles) in such applications as long- range oceanographic survey autonomous docking and shallow- water mine countermeasures requires an improvement of the vehicles manoeuvring precision and battery life. This can be achieved through the improvement of the vehicle control system. A vehicle dynamics model based on a combination of theory and empirical data would provide an efficient platform for vehicle control system development and an alternative to the typical trial and error method of vehicle control system field tuning. The development and verification of a six degree of freedom non-linear simulation model for the REMUS AUV is described. This is the first such model for this platform. In this model the external forces and moments resulting from hydrostatics hydrodynamic lift and drag added mass and the control inputs of the vehicle propeller and fins are all defined in terms of vehicle coefficients. The derivation of these coefficients is briefly described. The equations determining the coefficients as well as those describing the vehicle rigid-body dynamics are left in non- linear form to better simulate the inherently non-linear behaviour of the vehicle. Simulation of the vehicle motion is achieved through numeric integration of the equations of motion. The simulator output is then verified against vehicle dynamics data collected in experiments performed at sea. The simulator is shown to accurately model the motion of the vehicle. Finally recommendations for future modelX42039

The metocean conditions contained in the 21st edition of API RP2A last updated in 1993 are in the process of being revised to account for: the effects of recent major hurricanes; the shift of production to deeper water; and improvements in our understanding of metocean conditions in US waters. As the Oil Industry has moved into the deeper Gulf of Mexico waters it has become exposed to strong currents generated by the Loop Current its associated eddies and by topographic Rossby waves. This paper describes the basis for the draft extreme conditions that have been developed for these strong deepwater ocean currents. Further work is underway to develop conditions for extreme near-bottom currents on the continental slope and for joint hurricane-Loop currents. Once accepted by API the conditions will ultimately be published as part of a stand-alone API RP (recommended practice) which will in turn be referenced by other API recommended practices such as those addressing shallow-water fixed platforms jack-ups deepwater platforms and floating MODUs. The Metocean RP will also include hurricane-generated conditions the development of which is documented in a separate paper.

Since the first HiMSEN H21-2 was launched in 2001 HHI (Hyundai Heavy Industries) has been developing new engine models of H25-33 H17-28 H17-24 and H32-40 continuously as a part of the HiMSEN family. Thanks to a variety in the range of power applied for projects and customer preferences for the HiMSEN concept of a PRACTICAL engine HHI has produced more than 1000 sets of HiMSEN engines for application in marine gensets marine propulsion and stationary engines. The most recent model H32-40 is being developed. This is the largest in the HiMSEN family and will cope with higher power demands. It is more economical and has the most ecological operation in the engine market. It has a 320 mm bore and a 400 mm stroke and cylinder power of 50 0kW at 720 rpm and 750 rpm. The output range is from 3000 kW to 10000 kW based on in-line and V type configuration of 6 to 20 cylinders. A unique common rail system and intelligent control system are also being developed and will be applied to this new engine in the near future as emission regulations getting ever more stringent. The design and development details of this new engine are described and the test results of prototype engine of eight (8) cylinders H32-40 is presented.

The confluence of recent initiatives in ocean observation offshore energy and port and harbour security has re-energised the many stakeholders in the marine technology industry in Southern New England to ensure that they are well positioned to capitalise on the opportunities. As traditional sources of research and development funding have decreased there has been a resultant shift which is forcing a new paradigm whereby industry academia and government must collaborate to leverage their complementary strength more than ever before. MAST (the marine science and technology) companies have significant market potential as an emerging cluster within the region's innovation economy. Massachusetts Technology Collaborative's JAII (John Adams Innovation Institute) contracted with the SCDP (SouthCoast Development Partnership) to characterise New England's MAST cluster and to assess the need and feasibility for an expanded and more unified MAST association. SCDP was also charged with determining an effective model for developing a strong voice for industry identifying market opportunities to enhance the growth of the sector and maximising the economic benefit to the region. Subsequently it was concluded that a stronger industry association was required to ensure the economic success of recent and emerging regional and national investments in the MAST areas for Southern New England. This paper presents the rationale data methodology and recommendations from the Marine Industry Cluster Development project carried out in 2007 and continued through theX29032

New advantages in science and technology such as time depth recorders have allowed researchers to study the dive behaviour of sea turtles in their natural habitat. Previous studies of dive behaviour of inter-nesting turtles have provided significant evidence on how to protect nesting turtles from human interactions. We examined the dive behaviour of inter-nesting loggerhead and green turtles and the risk of boat impacts at Casey Key Florida during the 2007 nesting season. The Florida Sea Turtle Stranding Network makes it clear that new management plans need to be implemented because of the increasing trend of boat impacts. Relative boat draft water temperature and daily activity of nesting female loggerhead and green turtles were documented with the use of TDRs (time depth recorders). The objective of the TDR study was to assess the correlation between surface intervals and daily activities and evaluate whether there are periods of increased surface activity that might infer greater risks of boat strikes. The results show that female loggerhead turtles are most active during morning hours which overlays with boat launches and departures at local boat ramps. Protective measures such as spatial and temporal boat restrictions are reviewed in this report.

The marine riser is a major component of offshore drilling and productions systems that are either fixed or floating. Since a marine riser is intended to remain in station for the productive life of an oil field; it will be exposed to wide variety of hazards with the potential for environmental damage structural failure or damage to the material. As part of the design process there are requirements of structural strength based on criteria referring to failure modes such as rupture by over loading fatigue failures buckling or unstable fracture. 3D non-linear dynamic analysis of a riser is carried out in the time domain using finite element solver ABAQUS-Aqua. The response histories so obtained are used to study fatigue and fracture reliability analysis of riser under random waves and random waves together-with vessel motion. In this study application of structural concepts for the evaluation of the fatigue resistance of marine risers including reliability techniques is presented. The limit state function has been established for cumulative fatigue damage using S-N curve approach and fracture mechanics approaches considering number of parameters random in nature. Reliability methods deal with the uncertain nature of loads resistance etc. and lead to prediction of the failure and a rational measure of the safety coefficient. RSM (response surface method) in conjunction with FORM (first order reliability method) has been used for reliability estimation. The results are compared with the Monte Carlo simulation method. The design point important for the probabilistic design is located onX38400

'An analysis of the technical and economic factors which control the commercial feasibility in the United States of manufacturing fuel gas from coal' Study undertaken by Battelle Memorial Institute as an assignment from the Gasification and Carbonisation Committee of the Technical Advisory Board of Bituminous Coal Research Inc. The results have been divided into two main parts. The first part deals with the technical aspects of fuel-gas production and the second part assembles information of the costs of transporting various fuels and discusses supplies, demand and prices of coal, gas and oil in the past. From the data, an attempt is made to predict price trends for each fuel in the future and thus to establish a competitive position of each fuel in the future. The general conclusion of the survey is that fuel gas produced at the mines by the cheapest known methods and piped to consuming centres cannot compete with natural gas piped distances four or even six times as far. On the other hand, producer gas has lesser costs than fuel oil and assures a steady supply of fuel gas. Chapters include the following subjects: Fuel-gas production, Manufactured gas, Producer gas, Water gas, Pipeline (high BTU) gas, economic aspects of petroleum and nuclear energy as a source of electrical power.

From the earliest times the Mediterranean and Black Seas have played an important role in the development of culture identity and history of countries bordering these two seas. However if a look is taken at the specific situation in the MediterraneanBlack Sea region now it will be discovered that the overall situation of the area continues to dramatically worsen in relation to the environment with potentially negative economic and social effects on the population. There is no single medicine that could be prescribed to heal the present situation. However one can identify at least three issues that should receive priority attention namely: ecosystem-based management approaches to the conservation and sustainable use of seas oceans and their resources; good governance; and maritime security. None of these issues could be addressed with a good chance of success unless women and youth are actively involved in them realiing that the future of this important region and the survival of the Mediterranean and Black Seas are in their hands. This presentation addresses in detail these three issues and the role of women and youth in this regard.