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The reliability of a structure or its probability of failure is an important factor in the design procedure since it investigates the probability of the structure to successfully complete its design requirements. Due to the complexity involved in the inelastic buckling collapse mechanism of stiffened shell structures the reliability analysis of submarine pressure hull in which failure is dictated by inelastic effects assumes great significance among structural engineers. In spite of many years of efforts to develop good prediction techniques for plastic and elastic-plastic buckling of stiffened shells and also to use the reliability concepts in the submarine pressure hull structures comprehensive and reliable methods are still scarce. Therefore a rigorous Finite Element analysis of a typical internally ring stiffened submarine pressure hull with failure governed by inelastic overall buckling has been carried out using the general-purpose finite element software NISA. The samples required for each random variable were generated using RPST (random polar sampling technique) in which the combinations of variates are obtained using a random polar sampling of Latin hypercube sampled values. For the obtained collapse pressures the reliability of the pressure hull structure has been determined and the effect of mean service loads on reliability has been analysed by taking different Central Safety Factors. The results were validated using Johnson-Ostenfeld Inelastic Correction method and the conclusions are advanced.

RC (reinforced concrete) structures have been used at early stages of offshore structural engineering in moderately deep-water environment. In deep-water environments RC structural components are an alternative solution for a stable structural configuration such as a floating concrete platform hulls and pontoons in harsh whether conditions. In this paper a general formulation of section-capacities of a circular RC tubular cross-section is presented. It is assumed that the strain-stress relation of the concrete in the compression zone is simply modelled as bilinear function with ultimate values given in Eurocode 2 and the concrete works only in the compression zone. Tension stresses of the cross-section are carried by the reinforcement. Having presented a general formulation of extreme bending moment and axial force of a RC monopod offshore tower under wave loading uncertainties in both section capacities and loading terms are presented. Next a reliability calculation of the cross-section is carried out. In this calculation the balance of the axial force is used to determine concrete compression zone during the reliability iteration and the failure function is defined on the basis of the section capacity- and applied bending moments. Variation of the reliability index with various parameters is investigated and most sensitive uncertainty variables are identified.

The use of a multiple ping active sonar approach is considered in order to track multiple targets. In most underwater target tracking applications that rely on active sonar observations the sonar sends out a single ping at each scan interval and receives returns that might either be from target(s) or due to clutter. It is proposed to use a multi-ping paradigm with the idea that the better detectability of more pings can assuming a high clutter density lead to better localisation of targets. However this introduces a timing ambiguity in the ping returns adding a new level of complexity in the data association. A MPDA (multi-ping data association) algorithm is proposed as a solution. MPDA formulates the assignment problem as a linear program which could than be solved using a primal-dual interior point approach. A comparison is made between three different scenarios: (1) the sonar sends out a single ping in each scan interval; there is no timing ambiguity (which return is due to which ping); (2) the sonar sends out multiple pings within a scan interval and the timing ambiguity is avoided by using orthogonal waveforms for each ping; (3) when the sonar sends out multiple pings each ping being an identical waveform within each scan leading to a timing ambiguity. A well-known multiple target tracking technique such as the JPDA is used in cases (1) and (2) while the MPDA algorithm is used to solve the assignment problem in case (3) and is shown to perform better than case (1) in high-clutter densities. Case (2) the unrealisable bogey

The role multibeam sonar for accurate seafloor mapping in oil and gas exploration and development is considered. It is described how until recently the high-resolution bathymetry data available to this industry was limited to single-beam echosounder data acquired concurrently with 2D or 3D multichannel seismic data. The bathymetry data produced by these systems left large areas of the seafloor virtually unmapped. It is explained how in order to produce a 3D rendering (image) of the seafloor from single- beam data it is necessary to fill in the gaps between widely spaced soundings by interpolating between the existing data points. However the seafloor renderings generated from such data lack the fine-scale detail essential to an accurate assessment of the morphologic character of the seafloor. MBS (multibeam sonar) data from numerous areas worldwide have been used to produce highly detailed seafloor renderings that have revealed the morphologically complex nature of the slope environment. These renderings have played an important part in dispelling the myth that the continental slope is a quiet low-energy environment. Multibeam data products are examined and a comparison is made between MBS and 3D seismic bathymetry. Tables and diagrams appear on pages 5 to 12.

The ARCDEV (arctic demonstration and exploratory voyage) project is presented. This project aimed to investigate the conditions for navigating an ice-classified tanker vessel between Europe and gas and oil fields in the Ob Estuary in north-western Siberia during winter ice conditions. The ARCDEV convoy was supported by near-real-time ice information taken from ERS2 and RADARSAT ScanSAR Synthetic Aperture Radar). Prior to and during the voyage a total of 28 satellite SAR images were acquired analysed and transferred to the convoy before its arrival to the area covered by the image. ERS2 SAR images obtained prior to and during the transit into the Ob estuary were used to select the navigation route through level ice avoiding hummocks ridges and other types of deformed ice which make ice navigation particularly difficult. The RADARSAT ScanSAR scene data offered a unique new opportunity to identify various ice types deformed ice vs. level ice leads polynyas and other ice phenomena important for the determination of optimal navigation routes. It was shown that the use of SAR data could improve the average speed of icebreaker escorted convoys by a factor of two. This improvement in ice navigation speed has important impact on both economic and safety factors of ice operations in the Arctic.

The long-term trend in demand for energy resources means that the Arctic will remain the focus of development plans in many organisations. The rise in resource-related projects has created the need for new approaches to assessing and minimising risk. The new tankers and drill ships required for the Arctic will be larger and stronger than any previous ships but will be very carefully designed and operated. This paper presents a methodology for assessing risk to large Arctic ships in a variety of scenarios. For the purpose of illustration fo the approach two ice collision scenarios are described. One is the case of a large ship with a bulbous bow hitting an iceberg head-on. The other is an aft waterline collision with a sea ice floe. Both scenarios are outside the conditions formally considered in standard ice class rules but are significant issues. The paper provides owners designers and regulators with an example of a methodology to examine ce loads using a rational set of design scenarios. The results show that vessels can easily be operated in a manner that can create dangerous load levels. The results are directly relevant to the structural design of new large Arctic tankers (oil and LNG) and large Arctic drill ships. The second part of the paper presents some initial results from consideration of plastic structural response to moving ice loads. The significance of the movement (sliding) of the load increases as the response level increases.

An investigation is presented into the use of satellite remote sensing to detect and monitor oil pollution in marine environments especially the offshore territory of the UAE (United Arab Emirates). Different ways of detecting oil spills and of storing data efficiently are shown. The ideal way would be to establish an operational monitoring system using remote sensing combined with near real-time satellite data and airborne data. This work is the first step towards oil spill monitoring of the offshore UAE and its adjacent waters. The synthetic aperture radar and the optical including thermal band imagery more than 100 scenes of JERS-1 SAR Landsat-7 ETM Plus Terra ASTER SIR-C/X-SAR ERS-1/2 and Space Shuttle photographs taken between mid-1980's and early 2001 have been examined. Continuous data acquisition and rapid analysis are the important factors for understanding the response from the sea surface to different phenomena and the time scale of any changes. The results show and confirm that the offshore UAE faces more than a few oil spills both in the Arabian Gulf and the Gulf of Oman. It is suggested that the forthcoming ESA's ENVISAT Japanese ALOS and Canadian RADARSAT-2 in conjunction with other widely available satellites will become decisive data sources for oil spill monitoring in the area. Diagrams appear on pages 7 to 9.

Most shipboard configurations of shafts and bearings are likely to be aligned when some or all of the centrelines of the bearings are offset from the theoretical straight line condition so as to achieve an acceptable bearing load distribution. The classic alignment technique would involve the calculation of the bearing reactions following a quasi-static analysis and varying of the bearing offsets until an acceptable set of bearing reaction forces or pressures is achieved. The reverse problem would be the calculation of the bearing offsets based on input bearing reaction forces or pressures. This can be done using a computer optimisation routine where the design variables are assigned to be the bearing offsets and the optimisation variable the reaction forces. Constraints can also be introduced such as the engine flange bending moment–shear force allowable envelope or the maximum/minimum shaft slope.This technique can save time by allowing the user to input the desired bearing reaction forces and other design constraints and dispense with the bearings’ offset multiple manual iterations. When this technique is customised in a user-friendly software environment it can become a powerful tool in the hands of the shipyard designer or consultant providing both independent design review and initial design features.The new software from Lloyd’s Register called ERA is shown to successfully

Bilge water consists of liquids that drain to the lower regions of the ship's hull. The composition of bilge water varies. Most US Navy ships and commercial vessels use coalescing oil water separators to remove the oil from water. This technology is relatively effective in removing free-phase oil however it is not intended to separate emulsified oils (oil droplets smaller than 20 microns) from water. These emulsions are created through the presence of chemical emulsifiers such as cleaning agents and solvents and by mechanical means from the ship's motion or transfer pumps. Oil-Water separation has become more difficult in recent years with the newer generation of ships with drier bilges and thus a higher concentration of oil detergents and chemical wastes in the bilge water. EnSolve Biosystems was contracted by NAVSEA (the US Navy Sea Systems Command) to investigate the feasibility of developing a biomechanical OWS (oil water separator) capable of cleaning oily bilge water to levels at or below 5-ppm. Furthermore the OWS was to be fully automated and capable of treating up toan equivalent flow rate of 10 gpm (based on an 8 hour per day operation). EnSolve's approach in carrying out this research was to leverage the knowledge gained from its PetroLiminator technology and modify certain physical and biological parameters in order to achieve the Navy's goals.

The contents are Ship design and construction Cost and currency affect newbuilding trends ECOFLEX ships and their advantages A new effective production carrier Advanced gas tankers Design for a turbine tanker New-generation post Panamax conbulk ships Passenger vessels Higly upgraded ro-ro conversions Advanced road rail and passenger ferry New-style Japanese cruise liners High-speed cargo and passenger catamaran Cruise newbuilding for Far Eastern markets Sea truck evolution and design Stabilised passenger accommodation Naval orders and developments world-wide High technology products key to Canadian yards' revitalisation Fincantieri design and construction of naval vessels Frigates - the new wave now building Submarine construction and refurbishment Make what the market needs The modern Midget-design and prospects for war Naval search and designation radars Combat control systems - man and the machine The choice of the multipurpose gun-the 100mm compact solution Shipyards Trends The modernisation of shipyard management and production The largest covered dock The scope and expansion of Damen Shipyards The modern marine railway dry dock That floating on air feeling Confirmed quality as a way of life The development of cranes Digital drives in crane control Bulk cargo discharge Cargo handling-one solution Controlled atmosphere equals fresher produce Inexpensive bulk nitrogen production An advanced multi- cargo refrigerating system Containerised transportation of liquids

Symp held in London July 28 - Aug 2 1966 Papers are Shipowners requirements Probable development in marine navigation 1966 to 1976 Optimum bridge layout Progress in marine radar and its possible relation to automatic control of ships in the future In control of ship borne radar Shipping regulation in port approaches Marine electrical systems Shipboard electrical engineering A.C electric systems in ships Some aspects of a.c. power generation in ships Power meters Unmanned engine rooms? Modern techniques in the control of ship machinery Data logging and automation of main machinery in ships Maintenance of instruments and automatic control efficiency Choice and layout of display instrumentation at the control centre in ships Trends in the design of marine diesel generating plant Noise abatement in ships The use of compressed air at sea Air clutches for marine propulsion Recent developments in marine refrigeration installations Modern trends in marine air conditioning Biological problems in the carriage of deciduous fruit cargoes Automatic control recording and measuring for perishable foodstuffs at sea Remote control techniques applicable to ships deck machinery Mooring of large tankers and bulk carriers The use of higher strength steels in ship construction Systems for the control of ship motions The effect of sea water on the adhesion of surface coatings The future of plastics in ships Developments in container handling Developments in the side loading transporters and deck auxiliaries

The USCG (Coast Guard) is currently complying with the International Convention for Prevention of Pollution from Ships (Marpol 73-78) Annex 5. The CG carefully evaluated the needs of its major cutters the equipment market search and an EA (environmental assessment) of the proposed alternatives before choosing marine incinerators as the primary alternative for safe disposal of solid and plastic waste onboard its major cutters. The type of marine incinerator chosen not only handles solid and plastic waste but can also burn waste oil and oily waste thus the CG avoids the segregation of plastic from food waste and also saves the cost of disposing of the waste oil. On smaller cutters where an incinerator cannot be retrofitted the CG has opted to install compactors and pulpers to handle the solid waste. The CG's solid and plastic waste management program its status success and recommendations are briefly described. The CG did not follow the Navy's design of solid and plastic waste handling equipment but rather considered the specific needs of its own cutters. The prototype incinerators were installed and tested by the Navy's environmental team and it was determined that they were complying with applicable IMO and US environmental laws and regulations meeting health and safety requirements and supporting the USCG mission.

A dynamic model-based control scheme is proposed for the stabilisation of an under-actuated under-water vehicle in the presence of slowly varying unknown disturbances. A UKF (unscented Kalman Filter) based on the vehicle's dynamic model is applied for the sensor fusion process to provide an estimation of the full state vector of the system. External disturbances and unmodelled phenomena are included in the dynamic model as zero-mean Gaussian white noise processes. The estimation of the state vector is used as feedback for the proposed control scheme which stabilises the vehicle to the desired position and orientation. The proposed methodology is experimentally implemented using a 3-DOF under-actuated vehicle. The efficiency of the methodology under various environmental conditions is shown by simulation results. The overall system can be used for inspection tasks of sea platforms e.g. during the inspection of a ship hull for possible damage tracking. Firstly the kinematic and dynamic modelling of the system are presented. Then the design of the UKF for the sensor fusion process is presented and the control scheme design is given. Finally simulation results and experimental implementation of the proposed methodology are presented and conclusions drawn.

Ideas and developments in electrical systems are being stimulated by progress in power electronics; nowhere is this more apparent than in the marine industry. Indeed it may be that such advances may lead to dc-distribution systems appearing once again in vessels. Concomitant with these developments is the need for new methods or adaptation of known methods to be found to deal with design and analysis problems that will invariably arise. The problem considered in this paper is identical to that considered in Part 1 ie that of a dc-supply feeding a constant-power load. This arrangement is one that is susceptible to stability problems. Work on this problem using the Nyquist criterion-based method has been reported1 and more recently using the root-locus technique.2 This paper is concerned with tackling this same problem using frequency-response methods specifically Bode diagrams. A stability assessment of the system can be made and some notion of the robustness of this stability ascertained. Further it is shown that if gain and phase margins can be determined and if the characteristic response of the system is dominated by the existence of a pair of complex-conjugate roots means of extracting the damping-factor and natural-frequency of an approximating second-order system can be easily established. Once this is achieved transient behaviour of the system to disturbances can be estimated.

The main function of a marine drilling riser is to connect the floating drilling vessel with the wellhead at the bottom of the sea providing both a conduit for the drill string and a return path for the drilling fluid. The drilling riser must be kept tensioned to avoid buckling. In general beyond a certain limit of water depth (e.g. greater than 450 m) it is necessary to use buoyancy modules in order to guarantee the riser tensioning requirements. These modules are strapped around each riser joint. As a consequence of the applied top tension and of the environmental loads the drilling riser is continuously subjected to tension and bending besides the internal and external pressures. Although the external surface of the riser joint is painted pitting corrosion underneath buoyancy modules is not unusual. The residual fatigue life of a corroded riser joint can be evaluated by means of a fatigue analysis based on S-N data. In this case nominal stresses are determined through a global riser analysis in which the drilling riser is modelled as a tensioned beam subjected to loads throughout its length and with boundary conditions at each end. The effect of the corrosion defects is taken into account multiplying the nominal stresses by SCFs (stress concentration factors) derived by local FE (Finite Element) analyses of the riser joints containing corrosion defects. Here stress concentration factors for a drilling riser containing corrosion pits are calculated using solid FE models.

Over the course of time many different approaches to measuring success in ecosystem protection-restoration activities have been developed and many lessons learned from both successes and failures. Various groups have recently begun to move from project-by-project use of outcomes assessment to develop policy standards for the use of success measures as management tools in ecosystems engineering. Coastal America's STAC (Science and Technical Advisory Committee) convened a workshop to review the current state of the art. The workshop focused on three procedures applicable to wetlands restoration and dam removal: the Hydrogeomorphic Method; the Success Criteria in Restoration Projects; and the Index of Biological Integrity. The value of these outcome measures for policy makers is limited because the assessments do not involve value judgments. Although the above procedures all incorporate reference sites they do not rank functions or incorporate either monetary considerations. To do so requires a convergence of ecosystems engineering and economics. While there remains no single clear standard for outcomes assessment in aquatic habitat restoration certain principles are increasingly accepted such as the need for procedures that can be tailored for specific habitat and that the appropriate comparators should be sets of similar habitats that have incurred a variable amount of human perturbation. These increasingly robust assessment tools will also serve as the foundation for increasingly sophisticated economic analyses. Thus there is the real prospect that policyX35937 Successful application of an integrated service contract to drill and complete oil wells in the South China Sea T K Sanders ; B Huculak ; Ming Jiang Zhang

The blackening of engine components in trunk piston engines especially in stationary power-generating DG sets running on residual fuel oils is common place. Blackening may cause severe operational problems such as the hampering of heat exchange when present in excess at hotter engine parts such as the piston under crown. The research findings and field performance validation data of assessing the blackening problems in case of trunk piston engine oils are covered. Two new laboratory-screening tests were developed to assess the asphalt dispersion and black deposit tendency of trunk piston oils. These new tests are able to distinguish the good and bad oils towards the said properties and have a good directional correlation between them. With the aid of these tests it was shown that irrespective of detergent chemistry any oil could be made less vulnerable towards black deposit formation by fine-tuning the overall polarity of the formulations. One such polarity-enhanced oil when tested for piston cleanliness properties in MWM-B engine test in both distillate and residual fuel operational modes showed consistent improvement. Back-to-back field validation of this formulation with respect to non-polarity enhanced one establishes the utility of the newly developed laboratory tests for optimising the trunk piston engine oil formulations.

When the International Convention on Load Lines was being written a decision was made not to cover yachts when used for pleasure. However a yacht is no longer solely a pleasure craft not engaged in trade. It has to earn its keep and is now frequently "engaged in trade" albeit to a small charter party or group of friends. Therefore strictly speaking the full requirements of the load line convention are applicable but they just do not work. Many yacht designers have problems meeting the requirements of any of the rules or regulations. In response to this the United Kingdom Maritime and Coastguard Agency developed "The Code of Practice for the Safety of Large Commercial Sailing and Motor Vessels" (LY1) which was later developed into "The Large Commercial Yacht Code" (LY2) both of which have been declared as equivalent to the load line convention. The Lloyd's Register's Special Service Craft Rules (SSC Rules) also contain requirements for items that are covered by the load line convention and some relaxations from the convention are allowed. In this paper a summary of the differences between the various requirements is presented together with flow charts to show which regulations are applicable to any particular vessel. Various alternative means have been found to achieve compliance and this paper describes what has been accepted and the reasoning behind the acceptance. Ths paper also addresses some of the issues that frequently arise when calculating freeboards for yachts.

The material on which the following work is based is derived almost entirely from Chinese official sources. The authors have no means of verifying the accuracy of most of this information. Though they have no reason to believe that official statistics are deliberately falsified, it is probably that they sometimes contain an element of wishful thinking. Certainly they are often so presented as to give as favourable a picture as possible of China’s economic achievements. Contents: The first tasks of the new government I. China’s traditional economy II. The economic objectives of the Chinese communist party III. The period of economic rehabilitation, 1949-52 The Five-year plans IV. The establishment of the planning machinery and the inauguration of the first five-year plan V. The operation of the plan VI. The great leap forward VII. Soviet aid The transformation of the economic framework VIII. The treatment of private enterprise IX. The new economic geography and the development of communications X. The organization of labour XI. Foreign trade The development of agriculture XII. Land reform XIII. The collectivization of agriculture XIV. The development of agricultural production XV. The control of consumption The prospects for the future XVI. The future development of the Chinese economy XVII. Conclusions Statistical appendix 1. Output of leading industrial products 2. Value of industrial production 3. Production of major agricultural crops 4. Capital investment in different sectors of the Chinese economy, 1952-5 5. Livestock population 6. Development of agricultural mutual aid and co-operation 7. Value of public and private retail sales of commodities

The beautiful coastlines of the US attract a large number of people. Yet there are numerous hazards that come with living in these areas. Of particular concern for the eastern and Gulf coast states are hurricanes. In less populated areas the threat is just as great. The barrier islands are one such example. The objective is to reduce disaster losses. This can be done by building communities that are resistant to hazards. With limited resources community decision-makers need the best information on what the hazard is what the probability is of the hazard occurring what and how great is the risk what are the likely effects of the hazard how those effects vary within a particular community and what mitigation can be taken. Just why the present situation is inadequate is discussed. The realisation that a better system for getting information into the hands of emergency managers and planners prompted federal agencies to form a task force to address the problem. From the discussion a recommendation for a GDIN (global disaster information network) was formulated. GDIN should be a robust integrated virtual network for co-operative exchange of timely relevant information used during disaster management to save lives and reduce economic loss. The appearance of the network is considered together with the next steps required. The benefits of GDIN are outlined.