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Many studies on long-term changes in zooplankton abundance and species composition for the European shelf seas have been based upon data collected by the CPR (continuous plankton recorder). The CPR consists of a towed body which is deployed from ships of opportunity along commercial routes. Data from the CPR survey over the past 40 years have shown that the abundance of copepods in many parts of the North Atlantic has declined indicating geographical shifts in the plankton communities. Because the CPR does not sample all zooplankton species with equal efficiency these observations may give a biased view of the overall changes. Here we compensate for CPR under-sampling by using previously published species-specific correction factors derived from comparison of catches may with WP-2 ring-nets and the CPR. The results indicate the importance of smaller zooplankton species in the ecology of the Northwest European shelf. The changes in community structure may have general implications for energy transfer efficiency to higher trophic levels and for the sustainability of fisheries resources. Materials and methods are presented and results presented and discussed.

Unexploded ordnance and sea mines threaten the freedom of the seas especially the freedom of naval manoeuvre in littoral waters. Sonars are used to locate classify and image underwater objects. Sonar detects these objects underwater using their acoustic reflectivity properties. The target strength of an insonified object defines the fractionof the incident sonar signal that is reflected or scattered backwards by the object. In general the target strength of underwater objects is aspect dependent so measurements are required over a complete 360-degree range of insonification angles. To achieve this for inert ordnance and exercise mines a monostatic sonar where the acoustic source and receiver are collocated at a large distance from the object is fixed and the object is slowly rotated about its vertical axis in a dam environment. For each insonification angle the echo returned from the object is composed of a number of components corresponding to discrete reflective regions or highlights on the object. Recent advances in ultra wideband sonar transducer technology enable these components to be resolved in the time domain. A further advance is to apply tomographic reconstruction techniques to the echo data to form an acoustic reflectivity map of the object. The map shows the shape of the object and the positions of various acoustic highlights. It is concluded that computed tomography is a valuable tool for analysing the spatial reflectivity of underwater objects.

Increased tourist trade and pleasure boat activities in the Ionian Sea have led to new constructions and expansion of existing marina facilities. A new site selected for marine development is on the island of Lefkada near the main town of Alykes. This area had previously been used for salt works and subsequently the area was flooded by sea water. The water was shallow. The area had also been used for dumping land fill soil. There was concern about the physicochemical characteristics of the seabed sediments. The area was dredged to provide reasonable boat operating depths. The EIA (Environmental Impact Assessment) procedures require studies to be carried out in order to obtain planning and construction permits. These described in great detail environmental indicators of the marine and coastal pre-construction environment. Dredged materials were also analysed to assess the quality and therefore the management-disposal strategies in order to avoid the dispersal of potentially contaminated sediments. Environmental data obtained before and after marine construction is presented and compared with the aim of reviewing the EIA process and investigating the degree to which a linear system such as an EIA is adopted and applied to a dynamic environment such as a marina.

Int conf held at Glasgow September 7 - 9 1983 Papers are Lloyds register approach to ship safety A challenge to structural failures in ships Safety and the Commonwealth of Australia Navigiation Act Safety of offshore platforms - classification rules and lessons learned Development of reliability based structural design criteria for tension leg platforms The role of the department of trade offshore Development and operation of fishing vessel safety centre for New England fisheries Safety at sea through manoeuvring standards LNG carriers - safety in operation Some collision and grounding considerations for refrigerated gas carriers Drifting disabled ships and offshore installations The prediction and practical measurement of ship squat in shallow water Safety aspects of heavy duty semi submersibles Simulation in marine activities Assessment of damage in offshore steel platforms Probabilistic analyses of environmental loading and motion of a tension leg platform for reliability based design Safety factor evaluation for cylindrical components of floating platforms in extreme loads Compressive strength of stress relieved ring stiffened cylinders including local damage How safe are design codes The tilt problem in semi submersibles A shipbuilders view of safety An effective method for treating the stability of marine vehicles Fishing vessel stability and safety Broaching - a note on some of the factors involved Prospects for a "rational" approach to marine safety Marine safety in cold regions Structural studies for increas safety A brief history of some recent ship accidents Profiting from losses Ship safety - the role of the consultant Investigation of threX40895 Marine and offshore training - can they be reconciled? D Doig CONFP

The presence of alcohol in the human body extends the response time of drivers. It is therefore the cause of numerous traffic accidents. Drivers must not drive under the influence of alcohol. The presence of alcohol in the human body needs to be determined and measured which can be done with the help of special equipment. With the adoption of the new Road Traffic Safety Act in 2005 the Slovene Police can choose the unit of measurement for measuring and determining the concentration of alcohol in the breath. Two units of measurement g/kg and mg/L are noted down. The main problem is choosing the appropriate unit of measurement. There is a connection between the two units of measurement as regards the correlation factor with which the concentration of alcohol in the breath is compared with the concentration of alcohol in the blood. Comparison of the Slovene legislation with the recommendations of the EU (European Union) will show which unit of measurement is suitable and appropriate for measuring and determining the concentration of alcohol in the breath. The choice between the units of measurement impacts on the procedure of measuring and determining the concentration of alcohol in the breath. In order to measure and determine the concentration of alcohol in the breath alcoscopes and ethyl meters are used. Alcoscopes play the function of indicators so their results cannot be the basis for taking measures against the violators of road traffic regulations. Ethyl meters are used by the poli Measuring and monitoring the effectiveness of ISM code compliance. Conference code: N1114 London UK 12-13 July 1999

The ever-rising cost of energy has accelerated the explorations for alternate energy resources. In recent years many countries have found large deposits of methane gas near seabed in deepwater but in the form of hydrates. Major efforts are underway to find ways to bring them for use on land at costs that are commercially profitable. A model to simulate the transport and fate of methane gas released in deepwater is presented. Methane gas when released deepwater undergoes a series of physical chemical processes as it rises through the water column from the seabed to the water surface. In the high pressure and low temperatures that are typical in the deepwater methane gas is likely to be converted to hydrates. These hydrates will be dissociated back to gas when they reach lower pressures and higher temperatures in the shallower regions. When a large amount of methane is released it is likely to form a plume. The model presented here takes the plume thermodynamics and hydrodynamics into account in addition to the physico-chemical processes associated with gases and hydrates. This model considers hydrate formation or dissociation gas dissolution hydrate dissolution gas bubble break-up and coalescence and the change of gas bubble size due to pressure and temperature changes. This paper presents the model formulation simulations of 'Deepspill' experiments and the comparison of the model results with experimental results.

The US Navy is one of the largest users of refrigerant CFC (chlorofluorocarbon)-114 in air-conditioning (AC) plants. These plants range in cooling capacity from 125 to 363 tons and are installed on all major surface combatants and submarines to produce chilled water for various mission-critical cooling applications including vital electronic and weapon systems. The domestic production of all CFCs including CFC-114 ceased in 1995. In addition to creating a mission-critical reserve of CFCs the Navy established an aggressive R and D program to identify safe ozone-friendly alternative refrigerants that could be used in existing shipboard AC systems. Since a 'drop-in' replacement for CFC-114 was not available kits had to be developed that would convert shipboard air-conditioning plants to operate with the new refrigerant. VGD (variable geometry diffuser) compressor technology and a microprocessor-based control system were used in the design of these kits to maintain the original design cooling capacity whilst improving the plant operating range and reducing structure-borne noise levels and part load power consumption. Prototype AC plants were converted and operation validated in the laboratory prior to a one-year-at-sea demonstration onboard USS Normandy (CG 60). The purpose of this paper is to document the Navy's R and D efforts and the conversion of existing shipboard CFC-114 air conditioning plants to an ozone-friendly alternative refrigerant.

Earthquake design of offshore platforms in seismic active areas is one of the most important parts of offshore platform design. In analysing a jacket type offshore structure in the non-linear range of deformation during strong ground motion the behaviour of elements in the non-linear range of deformation should be defined. The primary structural components of a jacket-type offshore structure consist of deck jacket and pile foundations. Pile foundations are an essential structural component of this type of structures and the SSPSI (Seismic Soil - Pile - Structure Interaction) is the key concern in seismic behaviour of this kind of structures. Here Fibre Element is used to model soil-pile interaction during earthquakes. In this model both pile and surrounding soil are modelled using fibre elements. The model is developed using DRAIN-3DX software. The behaviour of soil is assigned to fibre elements using p-y curves. In order to consider the effects of free field soil on motion EERA and NERA software are used. The behaviour of piles when they are embedded in sandy soil and subjected to strong ground motion is analysed and compared with available experimental results. The model can be used for soil - pile - structure interaction analysis of jacket type offshore structure.

The demand for natural gas is rising quickly and consequently the world energy market requires the transport of larger volumes of gas in the form of LNG. However the market calls for the collection of smaller volumes of LNG from more than one location. These requirements may be met by building large LNG carriers with capacities of over 200000 cubic meters and by operating these ships with the flexibility of partial filling of cargo tanks. Partial filling in membrane-type LNG carriers leads to sloshing and the loads generated may endanger the ship's structural integrity. Therefore it is necessary for the ship designer to know the magnitude of those sloshing loads and under what conditions they occur. A finite difference method is presented that was developed to numerically simulate sloshing in a membrane-type LNG carrier's tank. Model experiments are carried out to verify the results of the numerical method. The considered tanks are of a LNG carrier with a capacity of over 200000 cubic meters. The 3D numerical studies showed that the liquid inside the tanks exhibit different behaviour depending on the filling ratio and the encountered wave frequencies. Response characteristics due to the tank configuratioX46228 Numerical and experimental study of submerged flexible nets - applications to fish farms

The ultimate objective in the development of turbo-charger components (that is compressor and turbine) is to obtain a lightweight and compact construction exhibiting high efficiency while at the same time reducing costs and improving availability. This article deals mainly with geometry definition analysis and optimisation of the succeeding diffuser and casing components. The exhaust gas diffuser converts kinetic energy at the inlet into additional static pressure at the outlet. However as the gas condition at the outlet is determined by the ambient conditions static pressure at the diffuser inlet assumes values below its exit level. The reduced static pressure immediately downstream of the turbine rotor blade causes an increase in the enthalpy and hence an increase in turbine output power and efficiency. Measurements carried out at the turbocharger test-bed of MAN B&W document the influence of the diffuser on the turbine efficiency and turbocharger efficiency. Compared to a turbine without a diffuser the increase in efficiency of a turbine equipped with a diffuser amounts to about 2.5% points.

The implementation is discussed of dynamic under-balance perforating in a sub-sea development which helped address environmental concerns related to flaring during perforating. Use of a new perforating system implemented on recently completed wells has resulted in a significant reduction in flaring while maximising under-balance during gun detonation. The elimination of flaring has also simplified perforating operations resulting in significant time savings. The Terra Nova offshore field is located 350 km off the East Coast of Canada. It is a sub-sea development producing from a multi layered highly faulted oil reservoir to a FPSO (floating production storage and offloading) vessel. The development plan uses high productivity producer-injector pairs in the individual fault blocks to optimise recovery. Initially standard practice was to perforate wells using multiple runs of wireline conveyed guns up to 6 runs per well. In order to maximise completion efficiency the wells were perforated in an under-balance condition. The under-balance was generated by flowing back and flaring the well at the MODU (mobile offshore drilling unit) during each wireline run. The net results were multiple flowbacks per well with diminishing under-balance for each successive perforating run due to flare rate limitations. The multiple flowbacks increased the risk for environmental incidents due to unintentional releases while flaring.

The good state of hydrological resources is the main aim of any environmental policy. Its sustainability is an important concern at any international level. Directive 2000-60-CEE is the European Union's basic instrument to manage hydrologic resources in a sustainable way. Its main objectives are the progressive reduction of pollutant spills and the achievement of a good ecological quality of superficial waters. The first objective requires registering all the spilled substances and controlling their concentration in water. In the Canary Islands it is complicated to establish the substances to be analysed since the inventory of pressures is not updated. Therefore most of the very toxic compounds are in the Monitoring Program. As for the evaluation of ecological quality biological indicators and their quality thresholds are being defined by the intercalibration exercise which is organised among states that belong to the same ecoregion. The indicators proposed for the time being may not evaluate conveniently their ecological state. This was not predicted by the Directive which did not differentiate between the diverse Atlantic regions. Nevertheless if these subjects come to a consensus the European Union will be on its way to attain the protection of one of the most valuable resources in the near future: the water.

The monoswimfin applied from 1969 led to some kind of revolution in every type of underwater sport. It resulted not only in changing the way of swimming - from "front crawl" to "dolphin" but also in sharp increasing of the speed of swimming. In 1976-77 the author of this article jointly with the specialists in the sphere of hydromechanics and hydrobionics made researches on constructive characteristics of the monoswimfin being a component of the biotechnical system "sportsman-monoswimfin" and the main mover of this system. It was necessary to identify the most important parameters of the monoswimfim construction influencing the speed (velocity) of swimming with the aim of its further perfection and optimization. Evolution of the monoswimfin as a fin mover in 1969 - 2004 has brought the creation of a more perfect and effective monoswimfin which has resulted in the growth of speed swimming for the sportsmen. A look is taken at the development of the monoswimfin from 1969 to 2004 and its benefits.

Contents: Introduction -- Making the case for digital preservation -- Understanding your requirements -- Models for implementing a digital preservation service -- Selecting and acquiring digital objects -- Accessioning and ingesting digital objects -- Describing digital objects -- Preserving digital objects -- Providing access to users -- Future trends -- Appendices: Creating a digital asset register ; Digital preservation maturity model ; Systems, tools and services. Summary: "This very practical guide, offering a comprehensive overview of best practice, is aimed at the non-specialist, assuming only a basic understanding of IT and offering guidance as to how to implement strategies with minimal time and resources. Digital preservation has become a critical issue for institutions of all sizes but until recently has mostly been the preserve of national archives and libraries with the resources, time and specialist knowledge available to experiment. As the discipline matures and practical tools and information are increasingly available the barriers to entry are falling for smaller organizations which can realistically start to take active steps towards a preservation strategy. However, the sheer volume of technical information now available on the subject is becoming a significant obstacle and a straightforward guide is required to offer clear and practical solutions. Each chapter covers the essential building blocks of digital preservation strategy and implementation, leading the reader through the process. International case studies from organizations such as the Wellcome Library, Central Connecticut State University Library in the USA and Gloucestershire Archives in the UK illustrate how real organizations have approached the challenges of digital preservation."

Satellite remote sensing is now accepted as an important means for monitoring the world's oceans synoptically. Advances in remote sensing systems have resulted in instruments which are ideal for coastal investigations such as the CZCS (coastal one colour scanner) and the AVHRR (advanced very high resolution radiometer) which generate 1 km resolution data. On the other hand higher resolution (20-30 m) imagery such as Landsat and SPOT satellites may be more useful for the coastal area. Previous studies have been successful with remote sensing using their sensors to estimate water quality parameters (Chl.a (chlorophyll-a) SS (suspended solid) and SDD (Secchi disk depth)) in coastal waters. However these sensors have a few problems with spatial and radiometric resolution. Since the new satellite sensor 'ASTER' has high spatial spectral and radiometric resolutions its data can be much more useful for monitoring in coastal areas. ASTER data is compared with in-situ data (buoy data or ship data) for the estimation of sea surface temperature or surface chlorophyll-a concentration as first step to assess coastal environments using high-resolution satellite sensors. The preliminary study of monitoring for turbid coastal waters using a high-resolution satellite sensor Term-ASTER (advanced space-borne thermal emission and reflection radiometer) launched in December 1999 was examined. ASTER data buoy data and in-site water quality data (SST (sea surface temperature) or chlorophyll-a concentration)

3rd International Marine Systems Design Conf held Pittsburgh 8-10 June 1988 Papers are The subcavitating/supercavitating hybrid propeller An advanced method for design of optimal ducted propellers behind bodies of revolution Optimal hull forms for fishing vessels A knowledge-based system architecture for control of underwater vehicles Roll reduction by rudder control An integrated rig management system for a semisubmersible floating production vessel Computer aided navigation system (CANSY-II) Evaluation of impact loads associated with flare slamming Surface effect ship loads; lessons learnt and their implications for other advanced marine vehicles Advanced ship structural design and maintenance Methods of incorporating design for production considerations into concept design investigations Achieving customer and marketing orientation in marine transport system design Incorporating a seakeeping capability in a computer aided preliminary design system Hull form design - only a matter of the computer ? The components of the propulsive efficiency of ships in relation to the design procedure Design conception and CAE/CAD of hull form Direct curve and surface manipulation for hull form design Intelligent computer aid in marine design and ocean engineering Ship synthesis model morphology Teaching design for students of marine technology Operational aspects in ship design; the case of the roll on/roll off vessel The productive experience of 3D CAD/CAM techniques applied to ship design and construction A new concept for neat fit ship propulsion

Flexible pipes have been used for many years in offshore applications for the transportation of crude oil gas and water. Such structures are subjected to mechanical loads due to tension high internal pressure and dynamic motions which are sustained by the use of high-strength carbon steel wires. The steel wires are located in the annular space that may contain water and acid gas (CO2 H2S) which can be detrimental for steels. For that reason risks of SSCC (sulphide stress corrosion cracking) and HIC (hydrogen-induced cracking) are considered. Moreover for dynamic conditions presence of corrosive environment in the annulus could significantly reduce the fatigue performance of flexible pipe compared to air environment. The annulus composition is calculated using a permeability model that has been validated with medium-scale tests full-scale tests and field cases. In parallel corrosion and corrosion fatigue studies have shown that the annulus of a flexible pipe is a very confined space with over-saturation in iron and no renewal of oxygen. This results in a higher pH much lower corrosion rates and less HIC and SSCC than one would expect based on normal environments. Firstly after a short description of flexible structure the different results obtained during small-scale corrosion and corrosion fatigue tests are presented demonstrating the particularities of the annular space that limit corrosion. Secondly

The combination of high external pressures high operating temperatures and high levels of insulation places demanding requirements on the insulation coating of subsea flowlines that transport untreated produced fluids from a wellhead. Conventional wet coatings may not be able to provide the levels of insulation performance required to meet these criteria. In these circumstances the flowline must be made using a PIP (pipe-in-pipe) construction with dry insulation material in the annulus of the PIP. A large number of PIP systems have been installed throughout the world. Of these a small number have been installed using the reel installation method. CSO successfully completed the installation of the pipeline and umbilical for the BP Nile Project in January 2001. The challenges which had to be overcome for the BP Nile Project are described particularly from the standpoint of the reeled PIP design materials and fabrication. The innovative methods used to extend the PIP system for ultra deepwater depths of 2000 to 3000 meters or more are also described. These methods include detailed finite element design tools the provision of bulkheads to help in load transfer within the PIP system and the design and testing of innovative buckle arrestors. The active heating system is also described. This provides substantial improvements in flow assurance performance particularly for deepwater riser systems.

HFR (high-frequency radars) use HF waves (3 MHz to 30 MHz). They interact strongly with the sea surface and consequently are well suited to carry out remote sensing of the sea. Moreover HFR coverage is not limited by the radio horizon: it is possible to keep watch over the sea up to few hundred kilometres from the coast line (surface wave mode) or up to few thousands kilometres (space wave mode). Two wavelet-based processing are proposed in order to improve the detection and the sea clutter extraction. The two types of HF radar can both be used to derive oceanographic parameters (wave height surface current velocity wind direction and wind velocity) since HF waves strongly interact with the sea surface. The result of this interaction is the so-called sea clutter which is characterised by the sea spectrum. The first is HFSWR (high frequency surface wave radar). The second is the OTHR (over the horizon radar). Connection between sea clutter and oceanographic parameters is briefly described. The effects of ionosphere on the sea spectrum are also described. The proposed processing is related and results are detailed conclusions are drawn and future work is identified.

Table of Contents Contributors / v Preface / ix Ian K. Steele, "Introduction" / 1-13 John F. Bosher, "The Gaigneur clan in the seventeenth-century Canada trade" / 15-51 Nuala Zahedieh, "Credit, risk and reputation in late seventeenth-century colonial trade" / 53-74 R.C. Nash, "The Huguenot diaspora and the development of the Atlantic economy: Huguenots and the growth of the South Carolina economy, 1680-1775" / 75-105 Johannes Postma, "Breaching the mercantile barriers of the Dutch colonial empire : North American trade with Surinam during the eighteenth century" / 107-131 Olaf U. Janzen, "A Scottish venture in the Newfoundland fish trade, 1726-1727" / 133-153 Aingeru Zabala Uriarte, "The consolidation of Bilbao as a trade centre in the second half of the seventeenth century" / 155-173 Daniel A. Rabuzzi, "Cutting out the middleman? American trade in northern Europe, 1783-1815" / 175-197 Silvia Marzagalli, "A vital link in wartime: the organization of a trade and shipping network between the United States and Bordeaux, 1793-1815" / 199-219 Anna Agnarsdóttir, "The challenge of war on maritime trade in the North Atlantic : the case of the British trade to Iceland during the Napoleonic wars" / 221-258 Henry G. Roseveare, "Merchant organization and maritime trade in the North Atlantic, 1660-1815 : some reflections" / 259-267