Thrust allocation with linear constrained quadratic cost function

In this paper, a method of thrust allocation based on a linearly constrained quadratic cost function capable of handling rotating azimuths is presented. The problem formulation accounts for magnitude and rate constraints on both thruster forces and azimuth angles. The advantage of this formulation is that the solution can be found with a finite number of iterations for each time step. Experiments with a model ship are used to validate the thrust allocation system.

Prevention of Pollution of the Marine Environment from Vessels : The Potential and Limits of the International Maritime Organisation

--Critically discusses the role of International Maritime Organization (IMO) in the protection of the marine environment --Presents a clear, updated, concise and critical overview of the IMO marine environmental legal instruments --A fresh outlook on the north-south tensions in the IMO marine environmental discourses --Critically examines the principle of common but differentiated responsibilities in the context of IMO This book examines the role of The International Maritime Organization (IMO) in the prevention and control of pollution of the marine environment from vessels with a particular reference to the current north-south tensions regarding the strategy for combating climate change in the maritime sector as well as the prevention of marine pollution from the ship-breaking industry. The IMO, a United Nations specialized agency, has been entrusted with the duty to provide machinery for cooperation among governments for the prevention and control of pollution of the marine environment from vessels. The organization is responsible for drafting legal instruments as well as for facilitating technical cooperation for the protection of the marine environment. Although IMO legal instruments are mainly targeted at the prevention of pollution of the marine environment from vessels, there is a trend towards a liberal interpretation of this, and the organization has expanded its work to areas like shipbreaking, which is essentially a land-based industry.

Investigations of ultrafine particles emitted by ships and other transport modes in the port of Brisbane

This research measured particle and gaseous emissions from ships and trains operating within the Port of Brisbane, and explored their influence on ambient air composition at a downwind suburban measurement site. The ship and train emission factor investigations resulted in the development of novel measurement techniques which permit the quantification of particle and gaseous emission factors using samples collected from post-emission exhaust plumes. The urban influence investigation phase of the project produced a new approach to identifying influences from ship emissions.

Donald Ezekiel AM : passionate and innovative contact lens practitioner and manufacturer

Donald Ezekiel (known to all as ‘Don’) was born in Singapore on September 12, 1936, to a German mother and Iraqi father. His parents were Jewish refugees, who met in Batavia,1 married and alternately lived in Batavia and Singapore. The family established their primary residence in Singapore after Don’s older brother Eric (later to become a haematologist) was born in 1934. The Ezekiel family was forced to flee in 1941 when the Japanese bombed Singapore and were fortunate to obtain passage on a hospital ship to Perth. They returned to Singapore after the war but left again on their own accord in 1951 due to race riots. The Ezekiels sold up everything in Singapore and decided to settle in Perth...

Capturing natural-colour 3D models of insects for species discovery and diagnostics

Collections of biological specimens are fundamental to scientific understanding and characterization of natural diversity - past, present and future. This paper presents a system for liberating useful information from physical collections by bringing specimens into the digital domain so they can be more readily shared, analyzed, annotated and compared. It focuses on insects and is strongly motivated by the desire to accelerate and augment current practices in insect taxonomy which predominantly use text, 2D diagrams and images to describe and characterize species. While these traditional kinds of descriptions are informative and useful, they cannot cover insect specimens "from all angles" and precious specimens are still exchanged between researchers and collections for this reason. Furthermore, insects can be complex in structure and pose many challenges to computer vision systems. We present a new prototype for a practical, cost-effective system of off-the-shelf components to acquire natural-colour 3D models of insects from around 3 mm to 30 mm in length. ("Natural-colour" is used to contrast with "false-colour", i.e., colour generated from, or applied to, gray-scale data post-acquisition.) Colour images are captured from different angles and focal depths using a digital single lens reflex (DSLR) camera rig and two-axis turntable. These 2D images are processed into 3D reconstructions using software based on a visual hull algorithm. The resulting models are compact (around 10 megabytes), afford excellent optical resolution, and can be readily embedded into documents and web pages, as well as viewed on mobile devices. The system is portable, safe, relatively affordable, and complements the sort of volumetric data that can be acquired by computed tomography. This system provides a new way to augment the description and documentation of insect species holotypes, reducing the need to handle or ship specimens. It opens up new opportunities to collect data for research, education, art, entertainment, biodiversity assessment and biosecurity control. © 2014 Nguyen et al.

A robot application to marine vessel inspection

Seagoing vessels have to undergo regular inspections, which are currently performed manually by ship surveyors. The main cost factor in a ship inspection is to provide access to the different areas of the ship, since the surveyor has to be close to the inspected parts, usually within arm's reach, either to perform a visual analysis or to take thickness measurements. The access to the structural elements in cargo holds, e.g., bulkheads, is normally provided by staging or by 'cherry-picking' cranes. To make ship inspections safer and more cost-efficient, we have introduced new inspection methods, tools, and systems, which have been evaluated in field trials, particularly focusing on cargo holds. More precisely, two magnetic climbing robots and a micro-aerial vehicle, which are able to assist the surveyor during the inspection, are introduced. Since localization of inspection data is mandatory for the surveyor, we also introduce an external localization system that has been verified in field trials, using a climbing inspection robot. Furthermore, the inspection data collected by the robotic systems are organized and handled by a spatial content management system that enables us to compare the inspection data of one survey with those from another, as well as to document the ship inspection when the robot team is used. Image-based defect detection is addressed by proposing an integrated solution for detecting corrosion and cracks. The systems' performance is reported, as well as conclusions on their usability, all in accordance with the output of field trials performed onboard two different vessels under real inspection conditions.

A magnetic climbing robot for marine inspection services

Currently, the inspection of sea-going vessels is performed manually. Ship surveyors do a visual inspection; in some cases they also use cameras and non-destructive testing methods. Prior to a ship surveying process a lot of scaffolding has to be provided in order to make every spot accessible for the surveyor. In this work a robotic system is presented, which is able to access many areas of a cargo hold of a ship and perform visual inspection without any scaffolding. The paper also describes how the position of the acquired data is estimated with an optical 3D tracking unit and how critical points on the hull can be marked via a remote controlled marker device. Furthermore first results of onboard tests with the system are provided.

Wake angle for surface gravity waves on a finite depth fluid

Linear water wave theory suggests that wave patterns caused by a steadily moving disturbance are contained within a wedge whose half-angle depends on the depth-based Froude number $F_H$. For the problem of flow past an axisymmetric pressure distribution in a finite-depth channel, we report on the apparent angle of the wake, which is the angle of maximum peaks. For moderately deep channels, the dependence of the apparent wake angle on the Froude number is very different to the wedge angle, and varies smoothly as $F_H$ passes through the critical value $F_H=1$. For shallow water, the two angles tend to follow each other more closely, which leads to very large apparent wake angles for certain regimes.

Two-dimensional bow and stern flows in a finite-depth fluid with constant vorticity

This thesis is concerned with two-dimensional free surface flows past semi-infinite surface-piercing bodies in a fluid of finite-depth. Throughout the study, it is assumed that the fluid in question is incompressible, and that the effects of viscosity and surface tension are negligible. The problems considered are physically important, since they can be used to model the flow of water near the bow or stern of a wide, blunt ship. Alternatively, the solutions can be interpreted as describing the flow into, or out of, a horizontal slot. In the past, all research conducted on this topic has been dedicated to the situation where the flow is irrotational. The results from such studies are extended here, by allowing the fluid to have constant vorticity throughout the flow domain. In addition, new results for irrotational flow are also presented. When studying the flow of a fluid past a surface-piercing body, it is important to stipulate in advance the nature of the free surface as it intersects the body. Three different possibilities are considered in this thesis. In the first of these possibilities, it is assumed that the free surface rises up and meets the body at a stagnation point. For this configuration, the nonlinear problem is solved numerically with the use of a boundary integral method in the physical plane. Here the semi-infinite body is assumed to be rectangular in shape, with a rounded corner. Supercritical solutions which satisfy the radiation condition are found for various values of the Froude number and the dimensionless vorticity. Subcritical solutions are also found; however these solutions violate the radiation condition and are characterised by a train of waves upstream. In the limit that the height of the body above the horizontal bottom vanishes, the flow approaches that due to a submerged line sink in a $90^\circ$ corner. This limiting problem is also examined as a special case. The second configuration considered in this thesis involves the free surface attaching smoothly to the front face of the rectangular shaped body. For this configuration, nonlinear solutions are computed using a similar numerical scheme to that used in the stagnant attachment case. It is found that these solution exist for all supercritical Froude numbers. The related problem of the cusp-like flow due to a submerged sink in a corner is also considered. Finally, the flow of a fluid emerging from beneath a semi-infinite flat plate is examined. Here the free surface is assumed to detach from the trailing edge of the plate horizontally. A linear problem is formulated under the assumption that the elevation of the plate is close to the undisturbed free surface level. This problem is solved exactly using the Wiener-Hopf technique, and subcritical solutions are found which are characterised by a train of sinusoidal waves in the far field. The nonlinear problem is also considered. Exact relations between certain parameters for supercritical flow are derived using conservation of mass and momentum arguments, and these are confirmed numerically. Nonlinear subcritical solutions are computed, and the results are compared to those predicted by the linear theory.

Notes on the future of critical discourse studies

In How to Do Things with Words, Austin (1975) described marriages, sentencings and ship launchings as prototypes of performative utterance. What’s the appropriate speech act for launching an academic journal? First editions of journals tend to take a field as formed a priori, as having “come of age”, and state good intents to capture its best or most innovative work.

Modelling collision potentials in Port Anchorages: Application of the Navigational Traffic Conflict Technique (NTCT)

Despite the extent of works done on modelling port water collisions, not much research effort has been devoted to modelling collisions at port anchorages. This paper aims to fill this important gap in literature by applying the Navigation Traffic Conflict Technique (NTCT) for measuring the collision potentials in anchorages and for examining the factors contributing to collisions. Grounding on the principles of the NTCT, a collision potential measurement model and a collision potential prediction model were developed. These models were illustrated by using vessel movement data of the anchorages in Singapore port waters. Results showed that the measured collision potentials are in close agreement with those perceived by harbour pilots. Higher collision potentials were found in anchorages attached to shoreline and international fairways, but not at those attached to confined water. Higher operating speeds, larger numbers of isolated danger marks and day conditions were associated with reduction in the collision potentials.

Boarding Control System - for Improved Accessibility to Offshore Wind Turbines

This paper considers the dynamic modelling and motion control of a Surface Effect Ship (SES) for safer transfer of personnel and equipment from vessel to-and-from an offshore wind-turbine. Such a vessel is a key enabling factor for operation and maintenance (O&M) of offshore wind-energy infrastructure. The control system designed is referred to as Boarding Control System (BCS). We investigate the performance of this system for a specific wind-farm service vessel–The Wave Craft. A two-modality vessel model is presented to account for the vessel free motion and motion whilst in contact with a wind-turbine. On a SES, the pressurized air cushion carries the majority of the vessel mass. The control problem considered relates to the actuation of the pressure such that wave-induced vessel motions are minimized. This leads to a safer personnel transfer in developed sea-states than what is possible today. Results for the BCS is presented through simulation and model-scale craft testing.

Järjestö jäänmurtajana : Suomen merimiesunioni työmarkkinaosapuolena ja suomalaisten laivatyöntekijöiden turvallisuuden vankentajana 1944-1980

Like an Icebreaker: The Finnish Seamen s Union as collective bargaining maverick and champion of sailors social safety 1944-1980. The Finnish Seamen's Union (FSU), which was established on a national basis in 1920, was one of the first Finnish trade unions to succeed in collective bargaining. In the early 1930s, the gains made in the late 1920s were lost, due to politically based internal rivalries, the Great Depression, and a disastrous strike. Unexpectedly the FSU survived and went on promoting the well-being of its members even during World War II. After the war the FSU was in an exceptionally favorable position to exploit the introduction of coordinated capitalism, which was based on social partnership between unions, employers and government. Torpedoes, mines and confiscations had caused severe losses to the Finnish merchant marine. Both ship-owners and government alike understood the crucial importance of using the remaining national shipping capacity effectively. The FSU could no longer be crushed, and so, in 1945, the union was allowed to turn all ocean-going Finnish ships into closed shops. The FSU also had another source of power. After the sailors of the Finnish icebreaker fleet also joined its ranks, the FSU could, in effect, block Finnish foreign trade in wintertime. From the late 1940s to the 1960s the union started and won numerous icebreaker strikes. Finnish seamen were thus granted special pension rights, reductions on income taxes and import duties, and other social privileges. The FSU could neither be controlled by union federations nor intimidated by employers or governments. The successful union and its tactically clever chairperson, Niilo Välläri, were continuously but erroneously accused of syndicalism. Välläri did not aim for socialism but wanted the Finnish seamen to get all the social benefits that capitalism could possibly offer. Välläri s policy was successfully followed by the FSU until the late 1980s when Finnish ship-owners were allowed to flag their vessels outside the national registry. Since then the FSU has been on the defensive and has yielded to pay cuts. The FSU members have not lost their social benefits, but they are under constant fear of losing their jobs to cheap foreign labor.

Stakeholders' assessment of welfare indicators for sheep and cattle exported by sea from Australia

An adaptive conjoint analysis was use to evaluate stakeholders' opinion of welfare indicators for ship-transported sheep and cattle, both onboard and in pre-export depots. In consultations with two nominees of each identified stakeholder group (government officials, animal welfare representatives, animal scientists, stockpersons, producers/pre-export depot operators, exporters/ship owners and veterinarians), 18 potential indicators were identified Three levels were assigned to each using industry statistics and expert opinion, representing those observed on the best and worst 5% of voyages and an intermediate value. A computer-based questionnaire was completed by 135 stakeholders (48% of those invited). All indicators were ranked by respondents in the assigned order, except fodder intake, in which case providing the amount necessary to maintain bodyweight was rated better than over or underfeeding, and time in the pre-export assembly depot, in which case 5 days was rated better than 0 or 10 days. The respective Importance Values (a relative rating given by the respondent) for each indicator were, in order of declining importance: mortality (8.6%), clinical disease incidence (8.2%), respiration rate (6.8%), space allowance (6.2%), ammonia levels (6.1%), weight change (6.0%), wet bulb temperature (6.0%), time in assembly depot (5.4%), percentage of animals in hospital pen (5.4%), fodder intake (5.2%), stress-related metabolites (5.0%), percentage of feeding trough utilised (5.0%), injuries (4.8%), percentage of animals able to access food troughs at any one time (4.8%), percentage of animals lying down (4.7%), cortisol concentration (4.5Y.), noise (3.9y.), and photoperiod (3.4%). The different stakeholder groups were relatively consistent in their ranking of the indicators, with all groups nominating the some top two and at least five of the top seven indicators. Some of the top indicators, in particular mortality, disease incidence and temperature, are already recorded in the Australian industry, but the study identified potential new welfare indicators for exported livestock, such as space allowance and ammonia concentration, which could be used to improve welfare standards if validated by scientific data. The top indicators would also be useful worldwide for countries engaging in long distance sea transport of livestock.

Kognitiva system i namngivningen av finländska handelsfartyg 1838-1938

This dissertation is an onomastic study of Finland s stock of ship names (nautonomasticon) recorded over the period 1838 1938. The primary material investigated consists of 2 066 examples of ship names from the fleets of coastal towns, distributed over five sample years. The material is supplemented with two bodies of comparative data; one that consists of 2 535 examples of boat names from the archipelago area at the corresponding time, and another that comprises 482 examples of eighteenth century Finnish ship names. This study clarifies the categories of names that appear the frequency of the names, formation, morphology, linguistic origin, functions, and semantic qualities. By comparing the material with boat names from previous centuries, and from other countries, the characteristics of Finnish vessel names are further highlighted. Additional clarification is brought to the chronological, regional, and social variations, and to the emergence of various forms of systematic naming. This dissertation builds on older research from other countries, and uses traditional onomastic methods alongside a more modern methodology. The approach is interdisciplinary, meaning that the names are explored using facts not only from nautical history, but also from a range of other historical disciplines such as economics, culture, art, and literature. In addition, the approach is socio-onomastic, i.e. that the variations in names are studied in a societal context. Using a synchronised perspective, cognitive linguistic theories have provided the tools for this exploration into the metaphorical and the prototypical meaning of the names, and the semantic domains that the names create. The quantitative analysis has revealed the overall picture of Finnish boat names. Personal names, names from mythology, and place names, emerge as significant categories, alongside nonproprial names in Swedish and Finnish. The interdisciplinary perspective has made it possible to explain certain trends in the stock of boat names, for example, the predisposition towards names from classical mythology, the breakthrough of names taken from the national epos Kalevala, names in the Finnish language from around the middle of the nineteenth century, and the continuing rise of place names during the latter part of the period 1838 1938. The socio-onomastic perspective has also identified clear differences between those ship names used in towns, and those ship names used in the archipelago, and it has clarified how naming conventions tend to spread from town centres to peripheral areas. The cognitive linguistic methods have revealed that the greater part of the vessel names can be interpreted as metaphors, in particular personifications, and that many names are related in their content and also form semantic networks and cognitive systems. The results indicate that there is a mental nautonomasticon that consists of a standard set of traditional ship names, but they also reveal the existence of conscious or unconscious cognitive systems (rules and conventions) that guide the naming of boats.