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Experimental and numerical research is presented which was carried out on a high-speed symmetric catamaran operating in the Gulf of Naples. The experimental research was jointly carried out on three egoisms. It was carried out to obtain indications on scale effects on the resistance components on the influence of the towing line position on the resistance model tests on the most suitable ship-model correlation and on the power prediction scale effect. A theoretical wave pattern analysis was also carried out by means of the application of a numerical panel methodology based on Rankine sources. The results from the numerical wave pattern were compared with the corresponding experimental results obtained by the longitudinal cut method (Sharma 1966). The comparison was carried out in terms of wave resistance wave pattern and free wave spectra. The results of this research may give indications about the power prediction for high-speed catamarans by model tests and by numerical wave pattern analysis.

A practical method to estimate wind loads on very large floating structures (VLFS) of mat-like shape are proposed based on results of wind tunnel tests. Differences between VLFS and conventional size structures are outlined. Three models are presented: a two dimensional model to investigate characteristics of frictional drag on large deck area considering wind speed profile near the sea surface; a three dimensional model to investigate wind direction influence on total drag as well as pressure distribution on side walls of the structure; and partial models for the structure corners of both convex and concave types to investigate pressure distribution on the side walls around the corners. The method for estimating wind loads is useful in determination of required number and capacity of mooring units.

The paper presents a comprehensive investigation into the effect of incidence on the current loading of a mini TLP by means of three-dimensional CFD computations. The robustness of the code is demonstrated by validation against established experimental benchmark data and by extensive convergence and sensitivity testing. The computational results show significant effects from shielding indicating that for a TLP type of floating structure the most critical heading with respect to current loading is in the range of 20" to 30". Comparisons carried out with design code recommendations suggest that if shielding effects are not accounted for current loading will be overestimated by as much as 30% by a traditional "engineering" approach.

This is a book about the development of ships and boats which have affected the history of Western civilisation. It concentrates on the ships themselves rather than on literary descriptions or artistic representations. It takes in the earliest seafarers in the Mediterranean and Near East; Greek, Etruscan and Phoenician ships and shipping; Romans on the sea; Greek and Roman harbourworks; ships of the Roman period and after in Britain; Byzantium 330-641; Scandinavian ships from earliest times to the Vikings; the Vikings and the Hanseatic merchants 900-1450; the maritime republics: medieval and Renaissance ships in Italy; the influence of British naval strategy on ship design 1400-1850; traders and privateers across the Atlantic 1492-1733; and waterways opening the New World.

A test program has been conducted using a geotechnical centrifuge to examine methods for improving the sliding capacity of spudcans by modifying the spudcan footing. The tests were performed on medium dense dry sands applying different kinds of spudcan geometry. A computer controlled loading system was used to simulate the load path a spudcan is subjected to in a storm. First the test program is outlined. Next the test technique is discussed. Finally test results are given indicating that the most significant improvement to the sliding capacity can be obtained by using a skirt.

With the advent of ECDIS (electronic chart display and information systems) the US Army Corps of Engineers began efforts to publish chart data on the inland waterways. Executive Order 12906 directed Federal agencies to make geospatial data holdings available to the public and the National Transportation Safety Board recommended that the Corps promote the use of electronic chart technology on inland waterways for safety of navigation. The data initiative began with the publication of data in CADD (computer-aided design and drafting) files. However the various formats layer structures and geographic projections proved unsuitable for electronic charting applications. Therefore the Corps committed to use the S-57 exchange standard and carried out pilot projects on the Atchafalaya River in Louisiana and a 200-mile section of the Mississippi River. These projects established a mapping scheme of Corps waterway data to S-57 format to produce the river data product known as IENCs (inland electronic navigation charts) and initial coverage of broader areas followed. Currently 30 IENC cells covering some 1000 miles of river are available for public access on the Internet.

The monotonic and cyclic shear behaviour of a volcanic soil Shirasu as a reclamation material is investigated. Shirasu usually has a high coefficient of uniformity and typically contains 20-30% non-plastic fines formed from the crushed remains of larger particles. A series of monotonic and cyclic triaxial tests was carried out on samples of Shirasu to assess the influence of the fines on the monotonic shear and liquefaction susceptibility. Tests were carried out both on the original particle size distribution and on the soil which had the fines washed out. The existence of the fines was shown to dictate the mechanical properties of Shiiasu when used as a till material. Shirasu is shown to have a low liquefaction strength and underwent flow deformation at low confining stresses.

As passenger ships become ever larger many authorities and operators have been forced to examine the stability and safety of the people on board passenger vessels including ROPAX and cruise ships. The design of these vessels has changed significantly. However prescriptive stability rules do not represent these developments. As a result the application of the IMO Weather Criterion for intact stability based on the effects of a severe wind and rolling to modern passenger vessels can result in requirements higher than the values that should be applied if correct parameters are used. The experimental study carried out by the Ship Stability Research Centre on the effect of Pod structure on roll damping and roll motion is presented. Results are presented and discussed and are followed by some concluding remarks.

Sigrist has installed more than 100 on-line UVF (UV fluorescence) OIW (oil-in-water) monitors in the past ten years for continuous monitoring of the oil content in produced water from offshore platforms. Various reports indicate that different specific parameters are affecting the fluorescence reading. Separation systems that were not working properly were investigated in particular sample preparation. There was also concern about the influence of droplet size and this was also investigated. The possible influence of chemicals and the use of a rotor-stator homogeniser for sample pre-treatment were tested. The results are presented. These show that the combination of chemicals and the use of a homogeniser may help improve the oil droplet size distribution which leads to higher fluorescence readings and possibly to better correlation with laboratory methods.

Wave-current interactions have considerable practical interest in coastal engineering and related disciplines. A 1D wave-current numerical model is presented for the simulation of irregular wave characteristics in a current field. The model is based on the Madsen-type extended Boussinesq equation and a wave-current dispersion relationship. The model is applied to the following current and adverse current fields. Numerical results show the modification of spectral density in a current field and it is also found that modification of spectral density depends on the current direction and its magnitude. Spectral densities decrease in a following current field and increase in an adverse current field. In an adverse current field the spectral peak shifts towards to the higher frequency but there is no substantial shift of the spectral peak for waves on following currents. For the same magnitude of current velocity an adverse current field has significant impact on spectral densities than a following current field.

Tsunami-induced coastal inundation is of great concern to civil defense agencies in Pacific Rim countries. Currently two questions related to tsunami run-up on rough coastal terrain need to be investigated. The first is whether terrain roughness has a significant effect on wave run-up and the second is what is the proper mathematical formula to model the roughness effect. An experimental study is carried out to investigate the maximum run-up of non-breaking solitary waves on both smooth and rough plane beaches. Artificial beaches with different slopes and bottom roughness are studied. The results show that for waves running up relatively steep slopes (eg 20 °) viscosity and roughness have little effect on the maximum run-up. In this case the inviscid long wave theories are adequate for predicting the run-up height. However for waves running up over mildly sloped beaches the viscous and roughness effects are found to be very significant and can reduce the maximum run-up by more than 50% compared with the inviscid predictions.

SMC (submerged moored cylinders) can be used for transporting oil gas and dredged slurry. They can also be used as tunnels for crossing deep-waterways. The costs of such structures are independent of water depth and thus are cheaper compared to the fixed directions. A SMC consists of a buoyant tube supported on tethers as mooring lines which are anchored to the seafloor at suitable intervals. The hydrodynamic behaviour of a SMC due to the action of oblique random waves is studied in a wave basin in a water depth of 3m. Open type mooring was applied and the model was moored with linear taut moorings. The pressures around the cylinder were measured. The horizontal and vertical forces on the cylinder were obtained by integrating the pressures and resolving. The experimental set-up and program are described. Results are presented and discussed. The effect of wave direction and the relative submergence of the model below the still water level on the forces on the SMC and the mooring forces are reported. Conclusions are drawn.

The Indus delta in Pakistan supports a diverse ecosystem and serves as a sanctuary for a variety of waterfowl and migratory birds. It is reported that the terrestrial wildlife has decreased in diversity due to reduction of freshwater into the delta from the River Indus. This is due to a severe tropical Cyclone 2A which landed in the lower Indus region of Pakistan in May 1999. A study to assess the environmental impact of the cyclone on the area is presented. A tidal surge caused seawater to spill into the brackish water lakes. The aquatic living resources wildlife local coastal fauna and flora have come under physiological stress. Remote sensing techniques are used to detect morphological changes in the area. The SPOT satellite Panchromatic and Multi spectral full scene data of the area for three different periods is obtained. The Satellite data is processed on ER Mapper 6.2. The analysis shows very prominent morphological changes on the wetlands of the area caused by the landfall of cyclone. The major impacts on the coastal wetland environment are discussed and imagery with the field data collected during the study is compared. Conclusions are also presented.

An attempt is made to determine some aspects of the inter- relationship between wake field propeller design cavitation and dynamic load. Theoretical procedures are presented for propeller design for determining the dynamic propeller load and for determining cavitation performance. The use and need for these theoretical calculation methods are discussed. Five-hole pitotube measurements carried out on a group of large tankers and container ships are analysed to determine if it is possible to derive properties of wake fields that are typical for certain types of ships. Based on this propellers are then designed for the vessels and conventional design procedures are critically reviewed. The combinations of nominal wake fields and designed propellers are analysed with respect to the dynamic load due to the inhomogenity of the wake field and the occurrence and extent of cavitation. Calculation programs based on unsteady lifting surface theory are used for the dynamic load. Programs based on quasi-steady propeller theory are used for the cavitation prediction. It is concluded that a detailed knowledge of the wake structure is required for accurate calculation of the dynamic load distributions and that it is necessary to incorporate cavitation minimisation criteria in propeller design procedures.

Int semn held in Tokyo Japan 3 - 9 February 1976 Papers are A bibliography of wave resistance of ships Linearized wave resistance theory Line integral uniqueness and diffraction of wave in the linesarised theory On nonlinear wave resistance theory Wave breaking resistance of ships Wave analysis State of the Art 1975 Application of wave analysis to tank experiment Hull form design derived from wave analysis Wave theory applied to practical hull forms Hull form design - its practice and theoretical background Catamaran hull form design Added resistance and propulsive performance of ships in waves Ship waves and wave resistance in a viscous fluid An approximation to Michells integral The line integral term in the wave resistance On the contribution of line integral to the wave resistance of surface ships On the second order velocity potentials of the thin ship theory by centreplance source distributions Non linear wave resistance and coordinate straining The sheltering effect of ship waves Some consideration on the sheltering effect of a ship with a long parallel middle body

Ninth annual conference of the Law of the Sea Institute, 'Caracas and beyond', held on 6-9 Jan 1975 in Miami, Florida. Papers are An interpretation of the Caracas proceedings Intergovernmental dimensions of international conferences Transnational and transgovernmental dimensions of international conferences Machinery for seabed mining; some general issues before the Geneva Session of the 3rd UN Conf on Law of the Sea National maritime limits; the economic zone and the seabed The role of FAO and of the regional organisations after the conclusion of the 3rd UN Conf on Law of the Sea Future fishing technology and its impact on the Law of the Sea Impact of the fishery technology on international law interrelation between fishing technology and the coming international fishery regime Future shipping and transport technology and its impact on the law of the sea Law of the sea and the security of coastal states Deep ocean mining technology and its impact on the Law of the sea The great nodule controversy The options for LOS III; appraisal and proposal

Detecting straight patterns like ship wakes on a SAR image is not easy because there is not a priori information on orientation and position moreover SAR images are Speckle noised. This article proposes to describe a ship wake detection technique based on the discrete Radon transform and the stochastic matched filtering (SMF) used in detection. The association of these two processes leads to a detection algorithm that only requires the knowledge of the second order statistics of the signal to detect and the noise. Experimentation on real SAR images show the efficiency of the technique.

In order to investigate the interaction between offshore structure and base ground subjected to seismic and ice loads a substructure on-line dynamic testing system was developed. A dynamic response analysis by computer and a pseudo-dynamic loading test which obtains the restoring force of material experimentally are combined by a computer on-line data processing system. The analyses were carried out on an offshore gravity structure based on sand seabed subjected to ice load and earthquake motion by this method. Unique response behaviour of base ground and structure was observed in this study.

This study aims to investigate the applicability of new materials to marine structures focusing on their durability. To this end a 5-year exposure test has been conducted from 1999 on 3 types of specimens (for corrosion observation tension testing and joint strength testing) made of 21 selected materials (6 nonferrous metals 8 steels 4 composite materials and 3 rope materials). The specimens are exposed at 3 sites: Okinotori-shima and Miyako-jima corrosive environments with high temperature and humidity and a thermo-hygrostatic room in a laboratory. This paper primarily reports on the results of appearance observation of specimens at Okinotori-shima and Miyako-jima carried out in 2002 as well as the findings from observation and experiments on specimens exposed for 3 years at Miyako-jima.

One of the important areas in ship development for the next generation of ships is thermal management. Good thermal management from large heat sources together with reliable cooling technology is the key to energy savings cost efficiency and upgrading a vessel's performance. In this study a conceptual design for thermal management configuration is introduced which will fulfil thermal handling requirements from various heat loads on board ship. The configuration adapts environments for the next generation shipboard cooling application on naval and marine vessels and proposes a model for the direct ship's hull cooling method using flat plate heat sink and water cooling as part of an integrated thermal loop system called TPCLT (two-phase closed-loop thermosyphon). The configuration trade-offs the applicable thermal handling methods for each kind specific purpose of equipments or devices and heat load network to gain the appropriate one. On this basis preliminary design study on the required configuration of the TPCLT with direct hull cooling method is described.