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Ship structures must be designed with adequate safety/reliability and their designs must be acceptable from an environmental and economical point of view. Target reliabilities have to be met in the design rules to ensure that certain safety levels are reached in design according to the rules. There are several steps involved in a process of determining target reliabilities in agreement with a risk based approach as recommended by Formal Safety Assessment IMO (1997 2001). This study concentrates on the second step of FSA i.e. calculation of the reliability level inherent in existing rules representing past practice when state-of-the-art models for environment loads response and capacity are adopted. Buckling of a ship deck in the extreme sagging conditions is considered. The suggested procedure is illustrated by three examples. The reliability calculations are carried out for the 'as build' stiffened deck plate thickness. Uncertainties involved in the suggested analysis procedure and their consequences on implicit reliability are presented. Implementation of the results in the risk analysis is discussed.

A mariner engineers' pocket book on mechanics, heat and strength of materials, also including electricity, refrigeration, turbines and oil engines. During his career the author made notes for his own use and the instruction of others he was teaching - he has compiled them as a useful pocketbook for marine engineers. The number of books a marine engineer can carry with him at sea is limited, so a handy compend of the various rules and tables is useful for reference. To keep pace with the times, considerable alteration has been made to this 3rd edition; the rules of boilers have been amended to conform with the new rules passed by the Board of Trade, Lloyds and the British Corporation. The sections on turbines and diesel engines have been brought up to date and oil fuel has received further attention.

The International Maritime Community has accepted that a major cause of serious sea accidents lies in corrosion causing deterioration in a ship's structural condition. Therefore shipping authorities and classification societies have decided to become more involved in protection against corrosion of critical structural ship parts such as water ballast tanks and bulk carriers' cargo holds. General regulations currently or soon to be enforced dealing with this issue are defined. Possible developments in the near future are also discussed and the current thinking of Bureau Veritas on this matter is outlined.

Proposed changes in legislation concerning the design and construction of newbuildings and modification of existing vessels and arising from the 1995 SOLAS Convention on ro-ro ferry safety the 1995 IACS requirements for the strength of vehicle deck closures and the 1992 SOLAS Convention on fire protection requirements are examined from the viewpoint of a naval architect and include specific discussion of Regulation 10 (location of collision bulkhead) Regulation 19 (integrity of ventilation trunks) Regulation 20 (air pipes terminating in superstructure) Regulation 20-4 (closure of bulkheads on the roro deck) Regulation 23-2 (integrity of hull and superstructure damage prevention and control) and Regulation 28-1 (escape routes on ro-ro passenger vessels).

The Swedish research institute SSPA Maritime Consulting of Gothenburg has evaluated wave load in five models of ro-ro visors with different bow forms from moderate to extreme flare and with different stem angles and a self-propelled model of the Estonia. The most probable maximum force on the five models over three hours was below the design force according to Lloyd's Register's 1982 Rules. The design forces according to the new Lloyd's Register Rules incorporating the IACS unified requirement are between 1.4-2.4 time larger than the old rules meaning that the safety margin is increased. One of the first ferry operators to take decisive action to improve and strengthen bow visor locking mechanisms in the UK's Caledonian MacBrayne with its ferry Hebridean Isles.

There is a diverse array of rules and regulations that govern the design and construction of tugs around the world today. These include the often conflicting requirements of the various IACS members and a multitude of individual national regulations and standards. Under SOLAS and Load Line rules many regulations that were conceived for full-size ships present major challenges to efficient tug design and operations with results that frequently do not necessarily improve the safety of the tug. The many discrepancies between rules for basic tug design and construction for some of the major IACS members are examined and the basis for a more uniform standard is proposed. For the purposes of comparison sample 'typical' tugs of length 24 m 30 m and 36 m are used as baseline cases. Topics of comparison include voyage classification hull construction outfitting towing gear machinery and piping systems and finally and perhaps most critically stability criteria.

Legal issues of marine cargo liability are discussed by lawyers by using specific examples to examine: the position at common law (the Giannis NK carrying groundnuts and wheat the Athanasia Comninos carrying coal the Amphion carrying fishmeal); the position under the Hague-Visby Rules for which the scheme of liabilities is discussed in detail with numerous examples (the Apostolis carrying cotton bales and suffering fire during repair the Subro Valor carrying peas and suffering fire the case of Maxine Footwear Co Ltd v Canadian Government Merchant Marine the Fiona carrying fuel oil and suffering explosion the case of Lennard's Carrying Co v Asiatic Petroleum Co Ltd and the case of Seaboard Offshore Ltd v Secretary of State for Transport); and the position under the Hamburg Rules for which the scope and differences from the Hague-Visby Rules are stressed. Throughout referance is made to interaction with other categories of regulation including the law of dangerous goods the ISM Code the Health & Safety at Work Act 1974 the Merchant Shipping Act 1995.

The calculation method of the rolling amplitude is examined with the aim of identifying weak points needing further studies and to propose some interim modification of existing procedure. The problems connected with the correct evaluation of the roll-back angle the wave steepness and the effect of wind are discussed on an experimental basis. After some introductory information a look is taken at mathmatical modelling of roll motion in beam waves and the experimental results with scale models of large passenger cruise ships. Next attention is given to possible changes in effective wave slope formula followed by experimental difficulties and future research programme experimental wind tunnel tests and consideration of the possible standards and procedures for the weather criterion calculation.

Classification Societies are independent organisations that promote the security of life property and the environment of ships and offshore structures. This is done by the establishing and administrating standards for the design construction and operational maintenance of marine vessels and structures. Classification rules and guides are largely of prescriptive nature and have been historically established from principles of naval architecture marine engineering and other scientific principles. Traditionally ship and offshore classification rules are formulated based on proven engineering principles and operational experience. With increasing frequency the marine and offshore industries develop new applications or processes for which existing classification rules may not be directly applicable. For this reason a new process for classification has been created to deal with a new design starting from the concept development stage. This new process draws upon engineering testing and risk assessments in order to determine if the concept provides acceptable levels of safety in line with current offshore and marine industry practice. Central to this process are risk assessment techniques which are used as a way to better understand and anticipate structural and operational issues related to the novel design.

The rules addressing safety at sea influence and characterise ship design at an early state especially in the case of vessels involved in passengers' transportation. For motor yachts in particular for those of significant dimensions and intended for commercial use the design constrains are prescribed in the MCA Code of Practice. Compliance with this code is appropriate for up to 12 passengers. However with ship size ever increasing in this area of the market designers are now considering complying directly with SOLAS requirements for passenger ships eliminating the 12-passenger limitation. So as far as the subdivision and damage stability requirements are concerned the new harmonised rules based on the probabilistic approach have been recently finalised at IMO and in subsequent years will be substituted by those based on the deterministic approach now existing within the current SOLAS. The significant revision of the regulation implies a strong change in the design procedure and in the definition of possible design solutions. Here the requirements contained in the three relevant rules (MCA SOLAS deterministic SOLAS probabilistic) are briefly described and compared

For some time now there has been an increasing demand for redundant propulsion concepts. Perhaps once in its lifetime a ship might experience an event which is beyond its capabilities. This could be during a storm and propulsion could be lost and the ship might not be able to control its behaviour. This might result in lives lost or even a ship lost with the associated pollution consequences. Although most ships are not equipped with redundant parallel propulsion systems ship owners and shipyards have requested that major classification societies evaluate redundant propulsion concepts. Equipping ships with redundant parallel propulsion systems is cost to the operating company. Safety and business costs are considered and evaluated. It is concluded that although redundancy can dramatically reduce the probability of spill and can thus be seen as a major advance against environmental damage it is better to invest in people - to have a skilled man who can turn his hand to reducing the consequences of any accident.

The background to classification and the role beyond safety of the Rules are reviewed and the challenges posed by the rapid changes in the regime for the management of safety within the marine industry are examined. Based on the developments by LR the response to change is described illustrating how some innovative developments that have been in place for some time are now even more relevant. The impact of Formal Safety Assessment (FSA) is discussed along with the human factors which dominate many of the risk scenarios. The form of the Rules of Classification is described. Management of risk and risk targets is discussed with respect to LR's modelling software packages including the FLEET system and a risk-based software tool LR MARINER. Surveying of existing ships and the ShipRight framework and feedback from service experience are also discussed.

The overall aim of the design process is to ensure that a structure can withstand with sufficient margin all foreseen load events. Offshore rules and regulations will typically define a set of rules to be followed by the designer. By fulfilling these it is tacitly assumed that the aimed safety level is achieved. The governing regulations and rules and not the least their interpretation may vary between various offshore regions. This may be the case both for the load side of the problem and the strength side of the problem. In connection with design of offshore structures the largest variability and uncertainty is typically associated with the load side of the problem. The aim here is to discuss the consequences of two rather common definitions regarding the characteristic environmental load to be used for design purposes: 1) The characteristic response is taken as the load for which the annual probability of exceeding it is q (here referred to as the q-probability load); 2) the characteristic response is taken as the mean extreme response of a sea state for which the annual probability of exceeding it is q (q-probability sea state). Results are shown for some generic response cases varying from a linear response case being rather insensitive to wave period to a quadratic response problem associated with a critical wave period band.

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.

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.

For the design of conventional types of ship structure classification society rules have provided a rational design guide for optimum structural weight as well as for safety aspects. In the design of new types of ship structure however existing rules may not be fully adequate because the design deviates from the experience incorporated in the rules. In this case an evaluation based on the ultimate strength of the whole structure is essential to ensure the margin of safety. A new double-hull tanker of 90000 dwt with a transverseless structural system which satisfies the requirements of US OPA 90 has been developed. The design philosophy focuses on oil pollution prevention by adopting a double-hull arrangement and with the help of quite simple structures taking into account a transverseless system. In order to evaluate structural safety of the hull in both the intact and damaged conditions deterministic and probabilistic approaches are used on the basis of ultimate hull girder strength. In this case the mean and COV (coefficient of variation) of both loads and strengths should be known. The mean of extreme vertical bending moment is estimated by direct calculation methods and the COV values are assumed based on existing data.

These Rules for lifting appliances in a marine environment cover derrick systems; cranes and submersible lifting appliances; mechanical lift docks; lifts and ramps; fittings, loose gear and ropes; machinery, electrical installations and control engineering systems; materials; testing, marking and survey requirements; and documentation.

The findings of the Committee of Inquiry into Trawler Safety 1969 were subsequently incorporated into the Fishing Vessels (safety provisions) Act 1970 and the Fishing Vessels (safety provisions) Rules 1975. The implementation application and content of the rules discussed with details on freeing ports freeboard stability fire precautions machinery boilers bilge pumps electrical installations and survey requirements.

A copy or similar version of an article that appeared in Lloyd's List under the heading 'Intertanko warning over "blind" application of SOLAS rules to chemical tankers'. It examines proposed rules for 'devices for preventing the passage of flame into cargo tanks' and how they would work (or not) realistically.

The development of rigidly connected integrated tug-barge (ITB) combinations according to American Bureau of Shipping classification society rules (particularly 1975 Rules for Building and Classing Steel Vessels subsection special considerations for nobel features) is discussed with reference to descriptions and illustrations of the design features and operation of connecting devices.