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Wave-induced hull girder loads such as vertical bending moment amidships are very important for design. The effect of heavy weather avoidance on the long-term wave-induced loads on ships is evaluated. Two hydrodynamic codes VERES based on a 2D strip theory and WASIM based on a 3D Rankine panel method are used to calculate the wave-induced loads and motions on various vessels. Two models for heavy weather avoidance are proposed. The first is based on the assumption that operational criteria relevant to vertical acceleration green water and bottom slamming are fulfilled. The second is based on the assumption that the sea state forecasts are available to the shipmaster and that rerouting is made. Based on the first model considering avoidance of heavy weather and the hydrodynamics results calculated from two codes wave-induced hull girder loads are obtained. The results are discussed - in particular the effect of different hydrodynamic codes and various scatter diagrams. The long-term prediction of wave-induced hull girder loads considering the effect of avoidance of heavy weather will give a relatively more realistic evaluation of the extreme hull girder loads. Finally the results from ship rules are also re-evaluated compared with the long-term prediction with and without heavy weather avoidance.

Combinations of 2-stroke diesel direct drives with gearless electric motors offer a lot of advantages in daily operation. Starting with direct fuel cost savings and maintenance advantages it leads to cleaner fuel burning with environmental benefits and an even a better degree of safety for the vessel (redundant propulsion). A fully automatic integrated waste heat recovery system reducing diesel engine driven vessels consumption and emission by 10-13% is presented. Safety issues for the individual components as well as the complete WHR System are discussed. Another issue of the WHR Systems installed on board vessels is the impact on the vessels design lay out of the engine room arrangement in the deckhouse arrangement of bunker tanks etc. It is discussed how the benefits of the integrated HR System can be used. Reference is made to a post PANMAX container vessel and a VLCC. Pollution of the air is permanently increasing. Unfortunately up until now there has been no parallel development to that of land-based sources of air pollution which has demonstrated a remarkable reduction since 2000. This may change now with the IMO Rules Annex 6 coming into force. Under the leadership of Siemens AG a group of renowned suppliers has been organised to deliver offers to shipping companies open to such innovations.

Title on spine reads Marine Engineering Essays, Problems and Demonstrations The present work is an attempt to exhibit in order and sequence some of the many applications of scientific principles to mechanical and marine engineering matters. In the choice of subjects the author has been guided more by the requirements of the marine engineer, but with a few exceptions the subjects dealt with are not exclusively marine. The selection has arisen out of the author's experience in assisting candidates preparing for the Board of Trade examinations for Extra First Class engineers. The knowledge required for these examinations covers an interesting and useful portion of the ground usually included in mechanical and marine engineering, so it is upon these lines the current work has been written. Contents include short essays on physical and engineering subjects such as sea water, electric current, entropy, iron ores, corrosion in boilers and softening water for steam boilers; solutions of questions in mensuration, for example in relation to riveted joints, stress and strain, shafts, beams, stability of ships, efficiency and horse power; proof of rules and formulae including common logarithms, kinetic energy, centres of gravity, strength and stress in boilers, thrust of a propeller and linear velocity of escaping steam. The appendix includes tables and examination papers.

Traditionally the AUV (autonomous underwater vehicle) design process has largely been 'ad hoc' with designs governed by experience and rules of thumb. Multi-disciplinary design optimisation has been increasingly used in conceptual design problems in many fields where a system level approach at the conceptual design stage can yield significant design improvements. Here a design optimisation process for an AUV is developed using a MOGO (multiple objective genetic optimisation) algorithm. The optimisation is implemented in MC (ModelCenter) from Phoenix Integration. It uses a genetic algorithm that searches the design space for optimal feasible designs by considering three MOPs (measures of performance): cost effectiveness and risk. The synthesis model is comprised of an input module three primary AUV synthesis modules a constraint module and three objective modules. The effectiveness determined by the synthesis model is based on nine attributes identified in the UDS Navy's UUV Master Plan and four performance-based attributes calculated by the synthesis model. To solve multi-attribute decision problems the AHP (analytical hierarchy process) is used. Once the MOGO has generated a final generation of optimal feasible designs the decision-maker(s) can choose candidate designs for further analysis. A sample AUV synthesis was carried out and five candidate AUVs were analysed. Conclusions are drawn.

Wave-impact related (slamming) loads can induce high stresses and cause deformation of local structural components. The accurate assessment of such loads is essential for the design of a ship's structure. Classification society rules contain formulas for slamming loads. Generally these formulae are adequate for conventional ships as they are based on operational experience. However for many modern ships it becomes necessary to resort to direct computations of slamming loads. A satisfactory theoretical treatment of slamming has been prevented so far by the complexity of the problem. Most theories and their numerical procedures were applied on 2D bodies; however slamming is a strongly 3D non-linear phenomenon that is sensitive to the relative motion between the ship and the water surface. Slamming is characterised by highly peaked local pressures of short duration. A numerical procedure to predict impact-related wave-induced (slamming) loads on ships is presented. The procedure was applied to predict slamming loads on two ships that feature a flared bow with a pronounced bulb hull shapes typical of modern offshore supply vessels. The procedure used a chain of sea-keeping codes. First a linear Green function panel code computed ship responses in unit amplitude regular waves. Wave frequency and wave heading were systematically varied to cover all possible combinations likely to cause slamming. Regular design waves were selected on the basis of maximum magnitudes of relative normal velocity between ship critical areas and wave averaged over the critical areas. Second a non-linear strip theory sea keeping code determined ship mot100094 Numerical prediction of model podded propeller-ice interaction loads

JAMSTEC (Japan Agency for Marine-Earth Science and Technology) is currently developing a new AUV (Autonomous Underwater Vehicle) which is capable of cruising in a very wide range and of observing seafloor topography. To achieve this mission the AUV has to be capable of long-time cruising. It also has to be able to detect the AUV's accurate position in order to cruise autonomously and correctly along a pre-designed observation course. Therefore the AUV is generally equipped with an INS (Inertial Navigation System) which calculates the absolute position of the AUV in real time. However the position data has an error caused by the drift-bias errors of the gyros and the accelerometers installed into it and this position error increases with time. A method is therefore proposed to reduce this error. In this method it is rotated around an axis according to some rules. This rotational motion causes the error reduction of the sensors. Consequently the position error is also reduced. In this paper the rotation control system used to apply this method to the AUV is described. The results of the experiment which is carried out to confirm the validity of the system using a land vehicle

Most navies recognise that as a result of the increase in global terrorism and their Government's expeditionary role for their Armed Forces an important shift is required in their warship's self protection capability against missiles. Previously the emphasis was associated with open ocean ASMD (anti-ship missile defence) whereas now it needs to address both the open-ocean and littoral threat. Parallel to this is a change in the extent of the control that governments exercise over their forces through increased stricter ROE (rules of engagement). Combine this with the need to avoid blue-on-blue actions in the crowded littoral and a requirement for an increased scope and related capability from ASMD arises. Discussion on capability soon relates to hard-soft kill balance and integration of all defensive systems layered defence and defence in depth. All of these are required and soft kill needs to play its part in achieving an effective 'Smart Kill'. The importance of a soft kill system approach is addressed together with the functions of passive countermeasures improvements that are being taken forward how modelling can help better understand performance how passive countermeasures can also gap fill for active RF countermeasures the importance of operator knowledge and finally an overview of the Smart Kill concept. It is sought to enhance ship defence against missiles by identifying key components that can combine together to increase the scope and effectiveness of soft kill passive countermeasures. Few in-serX11695

An improved sea mine computer-aided-detection/computer-aided-classification (CAD/CAC) processing string has been developed. The classified objects of 3 distinct strings are fused using the classification confidence values and their expansions as features and Fisher ratio based fusion rules. The utility of the overall processing strings and their fusion was demonstrated with new shallow water high-resolution sonar imagery data. Two significant fusion algorithm improvements were made. First a new nonlinear 2nd order expansion (Volterra) feature fusion algorithm was developed and an optimal subset of the Volterra features was selected during the training phase of the algorithm. Second another new nonlinear Box-Cox expansion of the features (raising the features to an appropriately selected exponent) was used in the fusion block. It was shown that when properly formulated the Box-Cox nonlinear feature fusion of the CAD/CAC processing strings outperforms the Volterra feature fusion algorithm and also yields an improvement over the best single CAD/CAC processing string providing a significant reduction in the false alarm rate.

Under Article 76 of UNCLOS (United Nations Convention on Law of the Sea) over 50 countries are eligible to claim a juridical Continental Shelf. If successful this would entitle them to have sovereignty over the resources of the seabed in areas beyond their 200-nautical mile EEZ (exclusive economic zone). Continental Shelves are not granted automatically: a case must be carefully prepared and defended before the Commission on the Limits of the Continental Shelf according to an elaborate set of rules. This preparation involves the disciplines of hydrography geology geophysics and geodesy. This important process could redefine the borders of one third of the world's states and change the legal status of vase areas of the world's oceans. The responsibility of hydrography to carry out its tasks to known levels of accuracy in this important process is discussed. Certain hydrographic elements are described and illustrated with examples from parts of the Canadian continental margin. Estimates of the accuracies of locating each one are produced and a model error budget for their combined effect is developed. The impact of increasing the accuracies achieved is expressed in terms of the area encompassed within the continental shelf of a Coastal State.

Ship structures are exposed to many types of loads and often overloading is related to extreme environmental action - wind waves and current - and accidental events due to collision grounding and explosion. Moreover damage and corrosion may reduce ship hull strength. In the past 10 years or so there has been great concern worldwide about the continuous loss of large tankers. A major contributing factor this is considered to be catastrophic structural failure. The hull girder ultimate capacity is an explicit control of the most critical failure mode for large double hull tankers. In order to ensure safe and economic design of ship structures it is necessary to accurately evaluate the ultimate hull girder strength of large double hull tankers. Based on long-time theoretical and experimental work assessment methods of ultimate strength of ship hulls are analysed and improved. Non-linear FEM (finite element analysis method) ISUM (idealised structural unit method) SM (simplified method) and AM (analytical method) are integrated into a software system of direct calculations of large tankers. Using this software system a comparative calculation is carried out on ultimate hull girder strength of a 300000 dwt double hull-tanker and the calculation results are compared with the single step procedure of Common Structural Rules for double-hull tankers (JTP CSR).

Fourth edition This is a revised and enlarged edition. This revision has been rendered necessary on account of the advances made during recent year in all details of ship construction, fittings and equipment, and regulations pertaining thereto. New chapters were added on Classification Surveys, Load Line Survey, Refrigerated Machinery and Plant Surveys, Survey for Passenger and Safety Certificate, Survey of Lights, Sound Signals and Life-saving Appliances, Annual Radio Survey, Inspection of provisions. Particulars of ship deratization, and also inspections, tests, etc., in connexion with the Docks Regulations (Factory Acts), are included. References to the Gyro Compass, the Echo-sounder, and the Wireless Direction Finder are made, since such aids to navigation are now in common use. The purposes to the book is therefore objects and it is hoped the few hints contained therein will, at least, provide the means of timely deliverance, and enable the seaman to act on his own initiative when called upon (1) to survey the damage to his own ship and prepare an intelligent report to his owners, (2) to estimate the approximate cost of repairs and draw up the necessary specification for tenders, (3) to supervise personally all repairs in hand and to satisfy himself that every details of the work contracted for is being honestly and efficiently carried out in conformity with the rules of the Classification Society in which the vessel is classed – not forgetting the usual attention to quality of new material and the preservation of strength where the old is replaced.

The present work is a treatise on the work, design and construction of small sea-going ships and inland vessels which are generally built in small or medium-sized yards. It describes and illustrates cargo vessels navigating inland waterways; coasters of up to about 1000 tons deadweight and cargo ships intended for sea- and river-work combined; passenger ships and ferry boats on coastal and inland waterways; tugs, towboats, ice breakers and fishing craft regardless of size; and barges for the transport of dredging spoils. The description of each type if preceded by an outline of the conditions under which ship and engines have to perform their work. For inland craft this covers the main features of waterways with their depths, currents, navigability and dangers; for coasters and tankers the properties of cargoes and the demarcation of coastal waters; for passenger ships and ferry-ships the rules concerning number of passengers and amount of cargo, freeboard, safety-means and life-saving appliances, and in the case of ferries the different ways of crossing and accosting at landing stages; for tugs, ice breakers and fishing craft the various methods of towing, ice breaking and fishing. There is a special chapter devoted to some aspects of resistance and propulsion on waterways.

For mooring chains of offshore floating production units API (American Petroleum Institute) recommends the use of its TxN fatigue curve considering the MBL (minimum breaking load) of an ORQ (oil rig quality) chain even if the chain has a higher grade. DNV (Det Norske Veritas) recommends the use of SxN fatigue curve where the stress is taken using the tension over the nominal area of the chain or wire rope. So it is easy to convert this SxN curve to a TxN curve or vice-versa. The geometry of the chain or wire rope and the material are implicit considered. To develop SxN curve for new accessories design it is necessary the using of FEM (finite elements method) to obtain the distribution of stresses and strains and the stress concentration factor and the SxN curves of the material. The analysis of the tension and the stress concentration factor will be used to obtain the slope and intercept parameters of the fatigue curve. The study developed for KS hook is presented together with how to obtain the fatigue curve for this accessory based on published papers rules and recent tests.

The UK MoD has a clear commitment to ensure that the risks to its employees and the public that are associated with its activities are controlled in a manner that is at least as good as that required by a national statute. For the warship this policy has been implemented by applying JSP 430 which requires the development of a safety case and certification in accordance with Naval Authority Regulations which themselves include the requirement to satisfy civil regulations where applicable. The implementation of JSP 430 on recent major platform projects has involved significant effort by the safety teams in order to provide the necessary justifications that the risks associated with the operation of the platform are broadly acceptable or Tolerable and ALARP. With the current movement to procure warships in accordance with Classification Society Codes for Naval Vessels the prescription provided by these rules goes some way to provide the necessary assurance that a platform is safe to operate in a military environment. However this approach does not address all aspects of safety on a naval platform and hence it is argued that there still needs to be a degree of risk-based assurance the level relevant to the military function of the platform. The paper proposes a framework for reducing costs of warship safety assurance by making the best and most cost-effective use of civil approaches without compromising military capability. It is attempted to identify the areas of safety case development activity that have represented the most significant workload in the development of major platform safety cases.X36294 Cost-effective solutions for innovative applications

The -re-1990 America's Cup races have created widespread interest in the highly developed 12-meter yachts. This also extended to the enthusiasts of R-C (radio-controlled) model sailboat racing. The production of hull for R-C racing started as early as 1968. A one-design class later evolved and was organised around the Morgan design and became known as the EC-12M (East Coast 12-metre) class yacht. Since the class was organised in 1971 a number of manufacturers have been authorised to produce EC-12M hulls from the Morgan-related plugs. As with many 'one design' yachts over time the hull manufacturers of the EC-12Ms began a series of subtle variations intended to improve the sailing performance as they sold the newer hulls yet still within the class rules. Some of the one-design fleet problems began to surface for the EC-12M as the newer hulls were built in the late 1980s. The hulls varied slightly but in significant ways. To answer these questions it was necessary to use a test method which would be relatively simple non invasive and reasonably accurate in order to determine both the radius of gyration and the location of the CG. Comparative evaluations were carried out using a Lamboley pendulum test to determine the radius of gyration in the pitch axis and to locate the centre of gravity of the EC-12M model sail yachts. The Lamboley simultaneous equations were solved using a computer programmed for this purpose. From these data the righting moment at 20 degrees heel and the moment of inertia in the pitch axis without the rig were calculated and plotted. Critical pitching frequencies were calculated assuming a nominal mast and rX38868

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.

Zeke's Island part of the North Carolina National Estuarine Research Reserve is an undeveloped site. The Reserve site is owned by the State of North Carolina and managed by the North Carolina Department of Environment and Natural Resources Division of Coastal Management as part of the Coastal Reserve Program. State statutes and rules allow compatible recreational uses and other activities on the Reserve. Although a fairly pristine and isolated reserve site the Zeke's Island Reserve is located near the communities of Wilmington Carolina Beach and Kure Beach. These communities attract significant numbers of in-state and out-of-state tourists and local residents each year. Many of these tourists and residents choose to recreate on the Zeke's Island Reserve due to its less crowded undeveloped character and nature. The effects of various recreational activities are investigated in a study. Based on the results it is concluded that the passive use of regulatory signs is an effective management tool in regulating visitor behavior within the Zeke's Island Reserve.

The book is based on 'Practical Yacht Construction' by C.J. Watts but is a revision due to the changes covering the whole field of yacht construction. It uses the original framework. Chapters 1 and 2 cover construction of keel, hull, decks and other parts but includes glues for main structural members and of plywood for decks, changes in metal fastenings etc. Chapter 3 covers engine seating, anchor arrangements, davits, cavils, stern chocks or archboards. Chapter 4 covers masts and rigging, with changes from gaff rig to the more efficient Bermudan rig and the introduction of aluminium masts, stainless steel standard rigging etc. Chapter 5 covers joinery work, plumbing, heaters, steering, ventilation, electric equipment and auxiliary propulsion. Lighter, more efficient joinery, better plumbing systems, plastic piping and improved ventilation have been introduced. Chapter 6 covers Thames tonnage, inside ballast, general arrangement, winches, pulpits and other fittings. Chapter 7 deals with the emergence of the glass-reinforced plastic hull, covering materials, moulds, methods of construction and notes from Lloyd's Rules repairs. The final chapter covers the introduction of special ship building alloys and a comparison with more traditional steel or timber construction.

The procurement of Naval Ships has changed dramatically over the last 20 years with the demise of Naval Dockyards as they have been privatised in many countries with the loss of the traditional naval overseer and the move to Prime Contractor managed procurement projects. included in this has been the growing use of Classification Societies to provide an assurance process for the navy both during procurement and perhaps more importantly through the long service life that a naval vessel must provide. Lloyd's Register has been as the forefront of supporting this transformation in the development of specific Classification Rules for Naval Ships and has worked with many navies in recent years both for new and existing vessels. in order to get the best value from the transformation of navla procurement that has occured changes in approach from the traditional process have been necessary and there is a need for personnel involved with procurement acceptance and operation of the vessels through life to understand the impact the transformation brings with it. These issues will be discussed and considered in the context of the need for many different procurement models to be available to suit a particular project but also consider some of the common problems that navies face and how they can be addressed.

UK Naval vessels have traditionally been constructed in accordance with the UK MoD's own standards and specifications. However the requirement to meet today's expectations for safety assurance has led the UK MoD to develop Naval Authorities responsible for the development of regulations and the subsequent audit of submissions for certificates of safety in defined 'key hazard' areas. There has also been an increasing movement towards the procurement of warships constructed in accordance with class rules developed specifically for naval vessels. Work is described that was undertaken by BMT Defence Systems Ltd and Lloyds Register on behalf of the UK MoD to determine the level of confidence provided to the Propulsion and Manoeuvring Systems Naval Authority by a vessel being maintained in either commercial or naval class. The objective was to identify any gaps between the risk-based requirements of the Naval Authority Regulations for Propulsion and Manoeuvring Systems and the deliverables provided by Naval Classification Services. The outcomes were to provide guidance to the Naval Authority as to what extent Naval Classification provides assurance that the 'key hazard' area is fully mitigated and to provide advice on the extent of material state verification required by the Naval Authority against that provided by the commercial procurement model. The work concludes that the regulatory approach can provide a significant contribution to the Safety Case approach and provides a pragmatic demonstration94739 Assurance of digital control accuracy at non-centralized stochastic actions J Ladisch ; B P Lampe ; E N Rosenwasser et al.