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Challenging emissions legislation requires manufacturers to comply with the decreasing levels of NOx and other exhaust emission species. An Emission Strategy Group has been set up between the three UK diesel engines companies to develop technologies for emission control to enable the group products to comply with current and future legislation. The methodology used both in experimental and predictive techniques is briefly described and the results achieved based on the 6-cylinder RK215 engine are discussed. This medium-speed engine is extensively instrumented and has been modified to enable high-speed in-cylinder combustion photography and gas sampling. A CFD (computational fluid dynamics) program has been adapted and validated by the engine to examine all influencing parameters on NOx control. The results show that significant NOx reduction can be achieved with minimum deterioration in fuel economy by using the appropriate injection system and by optimising the design of piston bowl to improve air/fuel mixing and combustion. Diagrams photographs and graphs appear on pages 10-15.

Subject to the 1982 UN Convention on the Law of the Sea the seas and oceans are classified into the following areas: internal waters territorial sea contiguous zone archipelagic waters straits used for international navigation exclusive economic zone continental shelf high seas and international sea-bed. These areas have international legal status and legal regime of passage for ships. Subject to the Convention the ship's right of navigation can be categorised as follows: right of innocent passage; right of archipelagic sea-lanes passage; right of transit passage right of free navigation; right of concessional navigation. Based on these a brief study on the ship's right of passage is presented. It is concluded that to grasp these legal regimes is of great importance to make good use of the oceans' resources to protect national interests of the sea and to maintain the safety of navigation.

A detailed analysis of causes resulting in phase errors in SAS (synthetic aperture sonar) is used to point out that the primary factors to affect developing SAS can be ascribed to the shifts of doppler centre and doppler rate for the irregular motion of the underwater carrier. Successively and estimating methods in image field based on multi-look processing are analysed and it is proved that these approaches are the better selections for SAS in the presence of both Range Migrant and Partial Aperture. A compensating and imaging complete SAS systemic design based on the auto-focusing method is provided together with a modified Range-Doppler imaging algorithm and a refined compensating step based on the PGA algorithm. Finally it is proved that this design is effective by real lake trial results.

Contents of the book comprise of the following chapters: Moving axes and relative motion (including theories and equations), Oscillations about equilibrium (Lagrange, Bernoulli), Oscillations about a state of motion (steady motion, Watt's governor), Motion of a body under no forces (Euler's and Kirchoff's solutions, the polhode, MacCullagh's construction), Motion of a body under any forces, Nature of the motion given by linear equations and the conditions of stability, Free and forced vibrations (Herschel's theorem, oscillations), Determination of the constants of integration in terms of the initial conditions (method of multipliers, Fourier's rule), Calculus of finite differences (agitation, Sturm's theorems), Calculus of variations (Hamilton, Jacobi, Helmholtz, Poisson theories), Precession and nutation, Motion of the moon about its centre (Cassini's theorem), Motion of a string or chain and Motions of a membrane.

There is a rapidly growing interest in MPAs (marine protected areas) as a tool for fishery management and ecosystem conservation. Evaluation of MPAs plays a crucial role in their management and redesign. This paper attempts to assess biological implications following the establishment of closed areas off East Iceland more than a decade ago with a focus on two for which sufficient data were available. The main question addressed here is whether the area closures have had any effect on the structure of the demersal fish community. The effect of reduced fishing effort on the demersal fish community following area closures in 1993 was analysed for two protected areas off the east coast of Iceland. The observed changes in the fish community in Breiddalsgrunn were reversed within 7 years of the reopening of the area to fishing. The possible causes for the observed patterns of response to area closures are discussed. Materials and methods are presented and results presented and discussed.

The effect of the homogenization heat treatment at 990C for 2h and 50 minutes on the mechanical properties and microstructural banding elimination of the API 5L X65 microalloyed steel was investigated. The investigated mechanical properties were the tensile strength the hardness the impact toughness and the fracture toughness (CTOD). After the homogenization heat treatment a normalization heat treatment at 940°C for 30 minutes was performed in order to refine the microstructure. The specimens in the “as received” condition were extracted from the plate on the L-T orientation longitudinal to the rolling orientation. The homogenization was effective on the banding reduction in spite of the ocurrence of a discrete undesirable ferritic grain growth. Tension and impact toughness properties after homogenization were below those properties in the “as received condition” but fracture toughness was improved.

Surface frost deposition takes place when humid air comes into contact with a surface whose temperature is below the dew point of water vapour in air and below the freezing point. Frost growth behaviour is difficult to model mathematically. A transient inverse geometry heat conduction problem (shape identification problem) is solved using CGM (conjugate gradient method) and BEM (boundary element method)-based inverse algorithm to estimate the unknown irregular frost thickness and shape. Frost growth is estimated using CGM and the results are justified using numerical experiments. It is concluded that frost shape can be estimated using CGM except for the first and last time. The reason for this and the improvement of this are addressed. Finally the effects of reducing the number of sensors and increasing the measurement errors on the inverse solutions are discussed. Results show that the accuracy of inverse solutions obtained by CGM remain acceptable as the measurement errors are increased and the number of sensors are reduced. Frost shape tables and diagrams appear on part of page 860 and continue on pages 861 and 862.

The Nautical Institute is an independent professional body for qualified mariners, whose principal aim is to promote a high standard of knowledge, competence and qualification amongst those in control of sea going craft. This book on pilotage and shiphandling includes an introductory chapter with definitions of terms and a brief history of pilotage, and succeeding chapters on pilotage organisation (including law, training schemes, economics and safety), planning pilotage and pilotage techniques (including optimising instrument navigation, balancing radio and visual navigation, charts and hydrographic publications, operating in ice and using tugs), traffic management (including traffic systems, legal and liability aspects and training), ship handling (including turning corners and manoeuvring, rudder design, performance, thrusters, ship and boat handling in surf and heavy weather, emergencies and notes on handling unusual vessels), bridge design and ship control (including classification of bridges, key factors in design, and propulsion systems and their control).

For the design of marine structures including cylindrical components the influence of neighbouring cylinders on the wave loading (interference shelter and amplification effects) cannot yet be estimated with sufficient engineering accuracy. In the Large Wave Channel at the Coastal Research Centre in Hannover wave loads on coastal and offshore structures can be examined at a very large scale thus minimising scale effects. Here large-scale wave experiments were carried out with single vertical and inclined cylinders. Additionally cylinder groups were investigated with special reference to shelter and amplification effects depending on cylinder spacing. Non-breaking regular and irregular waves as well as breaking freak waves were generated. The test set-up and some first results of the experiments looking to the maximum wave loads are reported.

A numerical model is presented in this study to investigate the wave transformation through a submerged permeable breakwater on a porous slope seabed. For this purpose the time-dependent mild-slope equation is newly derived for waves propagating over two layers of porous medium. This new mildslope equation involves the properties of the porous medium and it has the conventional hyperbolic equation form therefore is numerically efficient. The validity of the present model is confirmed based on the comparisons with the previous experiments. The effects of the permeable properties of both the porous seabed and the submerged permeable breakwater are then discussed in detail. The geometry of the submerged permeable breakwater to the wave transformation is also investigated based on the numerical solutions.

Understanding the relationship between fish biology and target strength potentially improves the accuracy of acoustic assessments. The effects of individual biological factors on backscatter amplitude have been examined but the relative contribution of each factor has not been quantified. Dimensionless ratios which facilitate comparison of disparate quantities were used to evaluate the effects of individual biological factors on echo intensities. Ratios from 25 adult walleye pollock were calculated using a Kirchhoff-ray-mode backscatter model parameterized for each fish. This comparative approach can be used to identify the influence of biological factors on backscatter intensity. A look is taken at methods followed by dimensionless ratios ratio applications and results. Next there is discussion.

In recent years the number of abnormalities in marine diesel engines caused by the poor quality of fuel oil has been steadily increasing. In particular the abnormal wear of the piston rings and cylinder liners of diesel engines causes serious problems for the safety and reliability of vessels. Therefore the role of on-board fuel oil pre-treatment systems is becoming significantly important. The actual capability of such fuel oil pre-treatment systems was investigated and a suitable pre-treatment method of fuel was studied. The test plant of a fuel oil pre-treatment system that simulated the on-board system was assembled on our shore facility. The test plant was plumbed so that various examinations could be carried out. Heavy fuel oils that were actually used on-board were provided for this investigation and in some cases test dust sludge from an on-board fuel oil pre-treatment system water etc. was added to fuel oil if needed. Oil samples from a test plant were analysed in the on-site laboratory immediately

Regulations have been introduced by a number of port states to prevent ships arriving in their waters from discharging ballast water which contains 'non-native harmful species of aquatic life forms'. LR (Lloyd's Register) investigated the various ballast water management methods with particular emphasis on the risks of the sequential method. LR's two- part study is presented which used 26 ships. The objective of the first part of the study - to investigate the effects of the sequential method on the ship's structure and the assessment criteria in respect of classification statutory and operational aspects. The objective of the second part of the study - the development of a safe operational envelope on the basis of sea-keeping analysis to control the dynamic effects for the ballast condition under consideration. Overall the study serves as a reference guide for Administrations who intend to develop ballast water management policies. The investigation raises serious concerns for the safety of most existing ship types and configurations using the sequential method of ballast water exchange and options to mitigate such risks are discussed.

The principal aim of this paper is to study the dynamic behaviour of offshore platforms subjected to wave loading. A general review of offshore structure wave loading and their effects on offshore structures are presented. A brief review on the basics of Wavelet analysis is also mentioned in this study. The techniques for modeling wave loading in finite element analyses are described and discussed in detail. A series of 3D analyses were carried out using the ABAQUS finite element software to study the effects on the dynamic response of the change in support conditions at the seabed. The effects of wave height wave period and wave velocity on platform behaviour were studied. The results from time history analysis are characterized using Wavelet Analysis in order to obtain the response pattern due to wave loading. These analyses allow the frequency response of the jacket structures to be described in the time domain. These results give a clear view on the response of jacket structure. The important parameters on offshore modeling have also been identified and discussed in this paper.

The freights' movement on the container ships market is presented for Panamax SubPanamax Handy Feedermax and Feeder categories. Decomposition analysis is used to reveal the long-term movement of the freight as well as their systematical mid-term movements. Decomposition Analysis is an algebraic method which is used to study the fluctuations of the time series after the smooth long-lasting central movement (underlying movement) of the time series has been statistically estimated. Finally a statistical study of the seasonal indexes which result from the decomposition analysis is being undertaken in order to recognise possible seasonal models with significant statistical effect on the freight values of the container ships' market. The normalization of the disagreement between the results was accomplished by the application of the ANOM - Analysis of means. According to this analysis only one seasonal index (December) seems to have a statistically important effect on the freights' values. The indicated seasonality model which arose from the volatility analysis of the seasonal indexes

Running attitude (i.e. draft trim angle and heel angle) of planing craft is commonly changed during manoeuvring. However a conventional estimation method of manoeuvrability for displacement-type ships neglects to take the effects of change in running attitude on the manoeuvrability into account because the change in running attitude is negligible and the effects of running attitude on manoeuvrability is also small for displacement-type ships except special hulls. For planing craft it may be difficult to apply the conventional estimation method. Therefore a new or modified estimation method taking some of the effects of change in running attitude into account is required to express its adequate manoeuvrability. Here these effects are shown using measured data from previous studies. According to the results the effectiveness of taking these effects of change in running attitude on manoeuvring hydrodynamic forces into a turning motion simulation is investigated. Conclusions are drawn.

Contents include: 1) Fire – Propagation of flames – Control of fire – Blanketing – Starving – Cooling – Application of Water - Ventilation; 2) Operational expedients – Which is the best media for extinguishment – Atmospheric isolation – Steam smother control – Gas producers by oxidation – Getting under the heat – Use of sea water – Working in smoke and fumes – Flooding problems – Stowage and its relation to fire conditions; 3) The study of the points involved in fire conditions; 4) Ship construction – Special types of vessels – Matters concerning the Fire Officer; 5) Sea valves and sea cocks; 6) Time taken to load and discharge ships; 7) Liaison with the Ship’s Officers; 8) Fires on ships in dry dock; 9) Ordinary fires on board – Fire risks when lying at and out of commission – Fires at sea or riding in Tidal waters; 10) Fires in holds and lower decks; 11) Fires in passenger compartments; 12) Fires in coal bunkers; 13) Fires in oil bunkers; 14) Fires in machinery spaces – Engine and boiler rooms; 15) Fires in ships fitted for cold storage; 16) Fires on oil tankers; 17) Self heating cargoes; 18) What can happen – some unusual fires; 19) Care of ships fire equipment; 20) Conclusion – Fire defence for shipping.

The diffraction problem of two bottom-mounted vertical circular cylinders is analysed. The randomness and directional spreading of sea waves are taken into account and a new procedure is proposed to estimate the largest forces on the bodies when extreme waves occur. Firstly extreme forces on the array of cylinders are obtained in two cases: 1) when a large crest occurs at a given point in the undisturbed wave field (which is the incident wave field in diffraction conditions); 2) when a large crest-to-trough wave height occurs in the undisturbed wave field. Finally it is investigated where extreme crests or crest-to-trough heights should occur in order to produce the maximum value of the force on a cylinder. It is shown that because the second condition is always the most conservative it is the most suitable to predict design conditions.

For effective support of offshore ice-resistant structures on the north-east Sakhalin shelf during winter season it is necessary to know the variability of ice-cover distribution over the water area. Consideration and forecast of ice-compression and ice-divergence zones will facilitate efficient planning of vessels operation to support offshore ice-resistant structures. Synchronous observations of ice drift based on three onshore RS (radar stations) allow the tracing of ice-cover distribution variation under changing metocean conditions in the near- shore zone of the north-east Sakhalin shelf. As a result of the study characteristics of ice compression and ice divergence are obtained. Maximum duration of ice-cover compression over the area is equal to 11. Divergence may reach 50% which means a 50% decrease in ice compaction. The phases replace each other according to reverse tidal fluctuations of ice cover based on one-day periods.

Wave flume experiments were designed to investigate comparatively dynamic wave pressures on single and on continuous cylinders with two different embedding depths in response to two wave spectra. The time histories of the water surface elevation and the corresponding dynamic wave pressures exerted on the cylinder are analysed in the frequency domain. The transfer function and spectral density for the dynamic wave pressure along the height and around the circumference of the cylinder are obtained. The experimental results of the single cylinder are compared to the theoretical results. Detailed comparison is also carried out between the single and continuous cylinders.