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In recent developments a sensor/data acquisition (DAQ) system that is mounted at the bit has been deployed which can monitor the behaviour of the drill bit and dynamic dysfunctions associated with the operating parameters different rock formations and rock/bit interactions. A modified shank accommodates the sensor/DAQ system. Its location was determined based on an extensive analysis of the bit's structural integrity. Initial tests verified the ability of the system to identify PDC bit dysfunctions such as backward whirl - one of the most bit damaging events in the drilling operation. Placing a sensor system in the bit allows for accurate pattern recognition and severity determination in terms of dynamic dysfunctions of the bit and can aid in optimizing drilling parameters in pursuit of increased ROP and reduced drilling costs.

In recent years speech recognition systems have been used in a wide variety of environments such as vehicle instrumentation. Speech recognition plays an important role in ships' chief engineer systems. In these systems speech recognition supports engine room controls but a SNR (signal-to-noise ratio) of lower than 0 dB is required. Therefore speech recognition systems operating in low SNR environments have not received much attention. This study focuses on a recognition system that uses body-conducted signals. A method is applied in which the specific nature of body-conducted speech is reflected within an existing speech recognition system with only small numbers of vocalisations. The effects of making such a system wireless are investigated. In an environment of 98 dB SPL within only one utterance of the learning data improvements of 50% or above of recognition rates were successfully achieved and recognition rates of 95% or higher were attained. These results showed the system to be effective.

'A handbook of rules, formulae tables etc. relative to material, scantlings, and pressures, safety valves, springs, fittings and mountings etc. for the use of engineers, surveyors, draughtsmen, boiler-makers and steam users'. It is stated in the Preface that it is hoped that the book will be of use in settling the scantlings for boilers in the process of construction and in determining the working pressures for those already made. Contents include sections on: properties of materials for boilers, iron boilers, steel boilers general aspects about boilers including testing and examinations of boilers. Presents numerous tables of data.

For the main materials and equipment of gas pipeline (pipes valves) the bidding process enabled bidders to submit financing directly linked to the goods supply. Judgement criteria were based on the present value of the bids. Therefore successful bidders were those who proposed the best price and financing conditions. This work deals with the different aspects related to purchase of goods having tied financial offers. Special focus is given to the several steps thereof from the bidding through effecting repayments having due attention to the judgement and getting proper accrediting from the governmental entities aiming at the authorization for the indebtedness and subsequent remittance of funds abroad.

This study follows on from a previous one in which a comprehensive test program regarding the static pressure distributions that develop over typical mast-sail geometries was described. In order to reinforce and confirm conclusions drawn previously from the pressure distributions alone a boundary-layer testing program has been carried out. This is performed over the suction surfaces of a typical 2D mast-sail geometry. Velocity profiles are obtained at a number of locations which together with visualisation data and the corresponding static pressure distribution are used to describe the fundamental nature of the complex partially separated flow field associated with such geometries. The velocity profiles are fully analysed to provide thickness parameters and skin friction coefficients suitable for use as representative data in the development of predictive theories involving viscid-inviscid interactions. The chord-wise variations of the thickness parameters are graphically presented and discussed.

Around 50% of all shipping accidents at sea are nautical ones. The term Bridge System is introduced as alternative way of thinking when addressing nautical accidents (grounding collision and contact accidents) which often are addressed as human errors. Human Error is the most widely used term in marine terminology when explaining accidents and especially those accidents that have originated on the navigating bridge. 80% of nautical accidents are said to be caused by human error. Here the term bridge system is presented in order to better address nautical operations and thereby reduce the number of human errors. A bridge system ensures that the vessel is navigated and manoeuvred safely from port to offshore installation and back to port by using correct course and speed in relation to waters and traffic and consists of 4 main parts: The Mariner the technical system the human-machine interface and operational procedures. Results from a joint industry project are presented. This project was established in order to address the bridge system onboard offshore service vessels. The end report from the project can be used as a guideline for specification design and verification by ship owners yards equipment manufacturers charterers and regulatory bodies.

Conference held 5th June 1996 Sheffield UK. Papers are:- Production and characterisation of steels - Milburn Design manufacture and heat treatment - Clarke The test rigs and gear stress analysis - Hofmann Pulsator testing - Ashby Surface fatigue and root bending fatigue test results for EN36 20 MnCr5 and SAE8620 gear steels - Sewell Nucleation of fatigue in gear materials - Evans and Shaw Gear scuffing and dynamic gear loads 160mm test rig - Hofmann Effects of micro pitting on the surface and root bending fatigue test gears - Sewell and Shaw Problems - Flank failures - Morgan Problems - gear cleaning - O'Hara and Ashby Grinding damage in carburised steels - Shaw and Evans Residual stresses in gears - Evans and Shaw The future programme - Hoyle and Flower

Recently high-speed ships applying aluminium alloy have been constructed. In general stiffened plates are widely used for the main structural members of the aluminium ships like in steel ships. It is therefore important to examine the buckling-plastic collapse behaviour and ultimate strength of aluminium-stiffened plates under thrust. Aluminium alloy is characterised by the high strain-hardening rate relative to Young's modulus and round stress-strain relationship above elastic limit. The reduction of strength (softening) in heat-affected zone of welded aluminium structures is also one typical characteristic of aluminium alloy. In addition the shaped stiffened plates with a taper cross-section in plate are widely used in aluminium ship structures. The influences of the strain-hardening rate stress-strain relationship welding residual stress reduced strength in heat-affected zone and taper cross-section on the buckling-plastic collapse behaviour of aluminium stiffened plates are investigated using FEM analyses. The simplified method to estimate the ultimate strength of aluminium-stiffened plates is developed considering the observed behaviours.

During 2003 the dry bulk market experienced a pronounced increase in freight rates. Many large bulk carriers were chartered. In response, shipyards experienced an ordering bonanza for bulk carriers. There are many well proven standard bulk carrier designs on the market, but new designs are also emerging as are shipyards with little or no experience in building bulk carriers. BIMCO's Marine Committee and the Marine Technical Managers Association (MARTECMA) thus felt that a Guide to reading and understanding a Newbuilding Specification was pertinent, in particular for owners not permanently involved in newbuildings. Ringbinder. There is a CD ROM affixed to the front inner cover.

Problems experienced during the late 1980s and early 1990s with bulk carrier structures resulted in losses of many bulk carriers. It was particularly disturbing to see the number of problems associated with relatively young vessels indicating a problem with design. Several measures were initiated by ABS IACS and IMO to improve bulk carrier safety and also operational and technical aspects. This resulted in significant changes to both SOLAS regulations and IACS rules with the introduction of a new hull structural strength and damage survivability provisions in 1997. A perspective on bulk carrier safety is presented. Several key critical structural areas and operational concerns that form the basis of IACS unified requirements and SOLAS amendments are identified. The ongoing amendment to the SOLAS convention is updated. The advantages and disadvantages of double hull bulk carriers are briefly presented along with the future common rules direction.

This treatise is aimed at recording the history of the cableship and the various companies and governments who have operated these vessels. Submarine cables have been laid in practically every ocean in the world, and an attempt is made to trace the history of the individual cableship operators and the cables which they have laid and maintained, the emphasis being on the marine side as distinct from the electrical engineering aspect of the cable characteristics, except where these have influenced the laying of a particular cable. The lay-out of the book is such that a separate chapter is devoted to each company or organisation operating cableships, with one of two exceptions where details of that company are vital for tracing some succeeding event.

The results are presented of a comparative study carried out for studying the performances of different anchor solutions for permanent mooring of a process barge offshore Congo. High capacity drag anchors driven piles and shallow caisson foundations installed by underpressure are amongst the solutions considered. The study shows that the caisson foundations offer the best solution both technically and economically. Their advantages include vertical load capability so allowing to reduce the anchoring pattern. Once positioned in the seabed each anchor's position is fixed and known accurately. Caisson anchors do not need to be proof-loaded on site simplifying the installation procedure.

Coccolithophores and associated calcareous phytoplankton are the most abundant calcifying organisms inhabiting our planet. Their fossil record is equally impressive perhaps being the most abundant and stratigraphically complete of any fossil group. As such they provide a valuable proxy for Mesozoic-Cenozoic phytoplankton health and robust data concerning rates and patterns of evolutionary change. Their present biogeography and diversity is closely correlated with climatic and oceanographic zones and their fossils provide a record of this relationship through time. The current understanding of calcareous nannoplankton evolution is reviewed using strato-phenetic phylogenetic models and a new synthesis of diversity data and rates of evolutionary change. The adequacy of the nannoplankton fossil record is discussed specifically potential preservational bias introduced by size delicacy and lifecycle coccolith dimorphism. Finally the temporal relationship between evolutionary events and the ocean-climate system is examined and the possible controlling mechanisms on nannoplankton speciation extinction and diversity is discussed.

Water quality analysis in marinas is essential for proper planning and operation. The evaluation of net volume of seawater entering each tidal cycle as well as concentration of diluted substances contained in the water is necessary. Evaluation is based on hydrodynamics and advection-diffusion analysis which can serve to determine low velocity zones and major concentrations of pollutants. Water quality was evaluated by differing spill over substances the diluted oxygen concentration and its biochemical oxygen demand. Additional ways to improve water quality in marinas are suggested.

There is an urgent demand for higher speed in marine transportation. The Trimaran has become a heated research topic and has turned out to be a promising displacement hull form over conventional hull form due to its hydrodynamic performance and other aspects such as speed and seakeeping as well as general arrangement and other attractive characteristics. Some research work on the theoretical evaluation methods of Trimaran ship resistance seakeeping hull-form and configuration optimisation is presented. Related model tests show that the methods presented are effective. The conclusions confirm that the Trimaran is an advantageous displacement type of ship if designed properly.

A study to investigate vegetative states in shallow bays of the Baltic proper to see if different vegetative states could be defined and to couple different types of dominating vegetation to the external load of nutrients is outlined. The external load of nutrients the water exchange time and the nutrient level in the water is investigated and determined if they could be linked to the vegetative state of a shallow bay and used as management tools. Three vegetative states were found and correlated both to the external load of phosphorus from the local watershed and to the total phosphorus (TP) concentrations in the water column. Study results suggest that the point at which a bay shifts from one state to another depends on the levels of the external nutrient load the water exchange time and the depth of the bay. It is also suggested that the TP concentration in the water is the single best parameter to indicate the state of the bay.

Risk design provides a rational method for safe design and operation of complex engineering systems. Capsize risk analysis and its application to the safe design and operation of intact naval frigates is described. A procedure is developed for determining the capsize risk of intact ships in irregular seaways. The availability of a fast and accurate program for predicting ship motions makes the procedure viable for practical application. Time domain ship motion predictions are combined with probabilistic data on ocean conditions and ship operations to evaluate capsize risk for naval frigates. Special attention is given to modelling the physics of ship capsize in severe irregular seas. This includes the effect of maximum roll angle of a ship in an irregular seaway. Predicted capsize risk levels can be compared with specified acceptable risk levels to determine safety of a ship for given operations.

This paper presents the background for a method of calculating the energy demand for different ship types. The method uses statistical analysis of the main parameters of different ship types to establish representative relationships between the cargo capacity and the ships main dimensions. The necessary propulsive power is calculated using well-established empirical power prediction methods. A method is developed to calculate the energy consumption as a function of three general parameters (the ship's capacity its speed and its average cargo utilisation). The exhaust emissions are then calculated. A comparison with road transport is also presented focusing on the energy demand and exhaust emissions per transport unit. Finally an economical evaluation of sea transport versus land transport is calculated using the external costs to society caused by the negative effect of different modes of transportation.

Tension leg platforms (TLPs) are an attractive concept for deepwater oil production because they are compliant in surge sway and yaw while minimising heave roll and pitch motions. Three case studies are presented that examine the forced lateral vibrations of the tethers of TLPs operated at low excess buoyancy and therefore low mean tension. A new semi-analytical solution based on the Galerkin technique is used to represent the tether's lateral displacement by a series of harmonic functions and to distribute the approximation error along the tether length. The analysis results include tether displacements and bending stress amplitudes. The case studies illustrate the dynamic response of tethers to platform excitation both for tethers at conventional tensions and at reduced tensions. It is concluded that cost savings and performance improvements could be achieved by designing TLPs with reduced tether tension.

In order to measure the characteristics of SMS (surficial marine sediment) acoustically it is necessary to examine the acoustic wave reflection characteristics from the surface of the SMS in detail. Recently it has been reported that the porosity and density etc. in the SMS vary largely with depth. The characteristics of acoustic wave reflection from such transition layer of the SMS seem to be very different from those from homogeneous sediments. The incident angle dependence of the reflection coefficient for the transition layer of the SMS model is calculated using OASES (Biot-Stoll model). The effects of the transition layer and the frequency dependence of the reflection coefficient characteristics are investigated. Next the characteristics of the incident angle for the reflection coefficient are measured in water tank and in situ. Beach sand (fine sand) is used for water tank measurements and in situ measurements are done in a very fine sand bottom. The measured results are compared with the calculated results using OASES and the effects of the transition layer on the characteristics of the reflection coefficient are investigated.