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A model for the simulation of open-channel-systems containing flow control structures (such as turbines and weirs) and involving slow (occurring during water level control) and fast (initiated by operational changes of load) transient problems is developed with particular attention to the computation of both steady and unsteady one-dimensional free-surface flow and to the computation of boundary condition at the junction channel / turbine. The mathematical procedure is described and verified in experimental studies of surge and suction wave characteristics in the head and tail races of the Rheinau and Birsfelden Power Stations on the river Rhine Germany.

The flow of soil over mechanical augers used for the placement of piles is computationally modelled using the generalised Newtonian fluid-flow model. Initially a constant coefficient of viscosity determined experimentally using a shear box test was used for the Newtonian case. To further improve the accuracy of the model rheological properties of sand were obtained using a rheometer and it was seen that the sand has a shear thinning behaviour. Qualitative validation was carried out through comparative analysis of streamlines seen from the computational simulations and scratch marks present on a scaled tool used in an auger test facility. The similarities between the computational and experimental results suggest that the soil when sheared beyond failure can be modelled as fluid using appropriate material properties.

The consolidation properties and stress conditions of deep sea sediments in the North Western Atlantic (illitic clays with varying amounts of calcium carbonate smectite and silt from near the Bermuda Rise and Blake Bahama Outer Ridge) and the North Central Pacific (illitic smectitic pelagic and authigenic clays from between the Murray and Mendocino Fracture Zones) have been determined by one- dimensional consolidation tests on a variety of different types of core sample (box standard piston giant piston large diameter gravity Kasten). Details include: location maps of the study areas; geologic setting and sediment types; equipment and procedures; and results comprising index properties consolidation properties and stress histories.

In the late summer and autumn of 2007 red tides were present in two prominent bays of the southern Benguela upwelling system False Bay and St Helena Bay. False Bay and St Helena Bay comprise the largest and most productive bays of the southern Benguela upwelling system. This article uses data from coastal monitoring stations and two ship-based transects supported by remote observations from aircraft and satellite to report on blooms within these bays during the late summer and early autumn of 2007. It also places the incidence and potential threat posed by these blooms in historic context and identifies the different physical forcing underlying these blooms by demarcating adjacent subsystems of the southern Benguela upwelling system.

In the last ten years the world Merchant Fleet has become highly sophisticated and technically improved economical safe and reliable human errors. However accidents still happen. To minimise human and material losses in navigation simulators (engine and navigation) are being increasingly applied both for training the students and also for training the seamen. By simulator training the knowledge experience and safety during work have been obtained since this method enables simulation of certain failures and conditions without human or material losses. PPT - 200 (propulsion plant trainers) is a dynamic real-time computer simulator where specific conditions of engine rooms with propulsion engines (MAN B&W SULZER) various diesel electrical and steam systems may be simulated. Training on this simulator is in full compliance with the STCW Convention. Interaction between the PPT-200 (propulsion plant trainers) computer simulator and pc-based models is discussed. The problem of load regulation and of regulation of shaft generator within the ship 's electric power system is analysed and discussed. The final goal is an optimisation of expenses.

This book provides an understanding of the characteristics, construction, operation, and maintenance of controllable pitch propellers. Those responsible for selecting and designing machinery systems, building and commissioning ships with controllable pitch propellers, managing or sailing them, or operating and maintaining ship’s machinery, will all find useful practical information and gain a general appreciation of the subject. Topics covered: brief history, characteristics of controllable pitch propellers and their resultant applications, definitions of terms used, forces and moments on blades, constructional and working principles, descriptions of hydraulic and control systems, installation design and setting-up, operation, ship handling, troubleshooting, and maintenance. In addition there is a discussion of the types of cavitation which may be experienced, of erosion and of propeller excited noise and vibration.

Mercy Ships is an international inter-denominational Christian humanitarian organization. Since 1978 this charity has operated a fleet of hospital ships in developing nations. During this time Mercy Ships have operated four ships Anastasis Good Samaritan-Island Mercy Caribbean Mercy and now the Africa Mercy. There are also two land bases in Sierra Leone New Steps for Polio and enforced amputation victims and the ACFC for VVF sufferers. The organisation is represented by 14 offices throughout the world with the International Operations Centre located in Garden Valley Texas. The UK office is in Stevenage and Australian office is in Caloundra Queensland. Over 90 percent of Mercy Ships people are volunteers who pay their own travel expenses to and from the ship crew fees whilst living and working on the ship and all personal insurances. In order to expand

The fleet of FPSOs and FSOs has been growing in pace with the number of offshore deepwater oil fields. The present fleet of FPSOs is composed of more than 65% of converted units and the fleet of FSOs of almost all converted units. The conversion of existing tankers into FPSOs or FSOs is usually quicker and more economical than newbuilding. Some aspects of FPSO and FSO conversion design for installation in deep waters are discussed. Critical issues such as the selection of the vessel to be converted and project start-up structural design installation of large-capacity production processing facilities are addressed. Diagrams appear on pages 7 to 10.

An attempt is made to assess the ways in which the crews of the four ships of humanitarian-aid missions who first broke the siege of Dubrovnik (and were the first to reach the hungry despairing people of that city in mid October 1991) coped with dangerous war situations. Also the effect on their health of the five-month period of close war contacts is considered. Firstly the subjects and methods are looked at. Next the results are given and discussed covering subjects' appraisal of war encounters coping strategies the adaptation status and psychosocial symptoms.

Indentation tests were conducted by pushing segmented indentors into the edges of freshwater ice sheets at different velocities. Ice crushing forces were measured independently in each segment. Results indicate that there is simultaneous generation of forces on all segments during low-velocity indentation but non-simultaneous force acting at high-velocity indentation. For brittle crushing of ice at high indentation rate the effective pressures measured during these tests are in the range of pressures measures in the field during the impact of ice floes against large structures. A statistical model was used and an estimate of correlation length is given in terms of ice thickness and indentation velocity.

Copper and copper alloys are among the earliest metals known to man, as they have been used from prehistoric times, and their present-day importance is greater than ever before. Their widespread use depends on a combination of good corrosion resistance in a variety of environments, excellent workability, high thermal and electrical conductivity, and attractive mechanical properties at low, normal, and moderately elevated temperatures. A wide range of cast and wrought alloys is available. For detailed expositions of properties and uses, the reader is referred to publications of many specialized aspects obtainable from the Copper Development Association offices in various countries. Relevant publications of the British Standards Institution include BSEN1982, Copper Alloy Ingots and Castings,1 and those covering wrought products.2,3 All ASTM standards relating to copper and copper alloys are included in a volume published annually.

This paper describes further investigations using small scale test cells into the general corrosion which can occur on wires within the inherent annulus space in a flexible pipe particularly and for the first time in a sour service (H2S containing) environment. The work enhances data presented previously in 2002. Tests have been performed in cells specifically designed to simulate as closely as possible the environment and confines of a flexible pipe annulus using solutions of both deionized water and seawater (to represent seawater flooding and condensed water). The systems were saturated with CO2 and H2S to simulate permeation of gases through the polymer pressure sheath (as predicted by validated permeation models). Weight loss measurements were undertaken in order to quantify the corrosion rate in these simulated annulus environments and metallography was undertaken to characterise the corrosion and check for HIC/SOHIC.

The application of subsidence monitoring and mitigation efforts combined with the conversion to remote operation have contributed to safely prolonging the operating lifetime of the best producing platforms in the Ekofisk field in the Norwegian North Sea. This paper is the first in a series of seven papers which summarise the main efforts done to mitigate the effects of subsidence. The background for the reassessment work is presented followed by the tasks involved and a summary of the main results. The assessment of four jacket structures at the Ekofisk Field is presented. Data tables and diagrams appear on pages 12 to 19.

General methodology and simulation results are described for risers coupled with a floating vessel. Equations of extensible riser and their finite element formulation are derived and are presented in the form which is suitable to accommodate the effects of contents flow and VIV. Non-linear riser equations are solved by iterations in global variables. The analysis procedure of coupling between the several risers and the vessel dynamics is described in detail. The low frequency coupled vessel motion and riser behaviour are numerically simulated. The internal flow effects are investigated in uniform and pulsating cases. It is found that the internal content flow makes the riser stiffer and the riser curvature reduced. In the VIV analysis the VIV excitation zone of the riser is obtained based on Eigen frequencies and the maximum response is evaluated from the corresponding eigen-shapes in the VIV region.

The transport of crude oil by sea represents a continuing source of pollution by cargo loss due to collision and grounding and by venting of VOCs (volatile organic compounds). The concept to be discussed here is to contain in-transit VOC emissions by maintaining a near constant ullage pressure. The results of experimental and theoretical analysis of crude oil under negative (sub-atmospheric) pressures are presented. The use of negative pressure in the ullage space of tankers has been proposed for the mitigation of cargo losses resulting from accidental hull rupture. This potential application resulted in detailed laboratory tests of various crudes over a range of temperatures and pressures. The findings were then applied to prevent or minimise VOC emissions occurring during transport of crude oil. Results are presented. A brief discussion on the design of a closed negative pressure system for VOC emission minimisation is discussed. The closed loop system along with a seawater heat exchanger mitigates the effects of temperature and pressures as well and will significantly reduce VOC venting to the atmosphere.

CSCAP (the Coast and Shoreline Change Analysis Program) is used by the RSD (Remote Sensing Division) to make more efficient use of its remote sensing resources to map the nation's coastline. The CSCAP procedure is described. CSCAP uses high-resolution contemporary imagery such as 2-meter SPIN2 orthorectified imagery and 1-meter IKONOS non-orthorectified imagery to detect shoreline changes when compared with nautical charts. The satellite imagery within CSCAP is then georeferenced. After georeferencing the resulting image is checked for positional accuracy. It is then used for comparison to the raster Nautical Chart or vector ENC (Electronic Navigational Chart). CSCAP is currently used as a planning tool to help set priorities in determining which regions require photogrammetric mapping. It provides as cost-effective means to update nautical charts within selected ports. Development activities currently focus on image geo-referencing accuracy assessment shoreline compilation procedures and compiled feature accuracy assessment. In addition new imagery sources are being evaluated as they become available.

This paper is about deploying practical rapid response Human Factors (HF) techniques to the design of CVF's key operational compartments. The CVF programme is introduced followed by the focus of the HF work being on the design of the key operational spaces: SCC Bridge Ops Room and FLYCO. A practical method of conducting Operability Assessments (OA) is described which involves scenario-driven workshops with stakeholders to test compartment layouts define manning and estimate screen real estate. The paper concludes with an outline of future HF work for the Design Manufacture and Integration Stage (DMIS) including user trials prototyping and screen interface design.

The volume provides a comprehensive reference to more than 16,000 names of common industrial and laboratory materials, giving relevant hazard information such as toxicity data. It also includes a listing of carcinogens, neoplastigens, mutagens and teratogens. Each material or substance entry includes general information and physical constants. There is also an analysis of flammability, explosiveness and disaster hazard. Finally, information on countermeasures to reverse or mitigate possible effects is also given for each substance. The following subject areas are covered: shipping, first aid, firefighting, toxicology, chemical incompatibilities, ventilation data, industrial noise, radiation hazards, sources and safeguards, hazards of solid waste production and disposal and identification and control of environmental carcinogens.

A study fleet is a subset of vessels participating in a fishery reporting detailed data that is used to characterise the entire fishery. These data can then be used to generate spatially explicit assessments of commercially important species and foster the development of more sustainable fisheries. A project was initiated to explore the technologies suitable for employing the study fleet concept to the New England groundfishery. The goals of the project were to outfit 12 vessels with suitable technology and implement the approach in a pilot demonstration. Described here are the electronic logbook and a data reporting system developed for this multi-species application and the Web-based interface used by fishermen to enter data on their fishing operation and to retrieve GIS maps of their reported data. The issues associated with the recruiting of study fleet participants are also discussed.

Kemigawa beach faces southwest. Its wind directions are described. The deformation mechanism of its artificial beach in Tokyo Bay was investigated based on field surveys. In 1987 beach nourishment was carried out and the shoreline parallel to the seawall was created. In 1991 in order to improve the beach's stability curved groins were built at the south and north ends forming wave calm zones in their lee sides. Large-scale shoreline changes were triggered due to the construction. Here the causes of the erosion of Kemigawa's artificial beach are investigated through field survey and shoreline analysis using aerial photographs. The stable shoreline is predicted using the modified Hsu's model.