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This article provides an overview of the recent advancements and updates made to the control systems of the OBSEA underwater observatory. The paper delves into the key technological enhancements implemented to improve the overall efficiency, reliability, and functionality of the observatory’s control systems. Topics covered include hardware upgrades, software developments, and innovative integration of sensor technologies. The article aims to highlight the significance of these updates in enhancing the capabilities of the OBSEA underwater observatory for monitoring and research in oceanic environments., Peer Reviewed

In addition to the potential global impact of climate change on marine ecosystems, the extensive use of high-impact fishing methods is a primary catalyst for benthic biodiversity degradation in the Mediterranean Sea. Implementing fishery no-take zones (FNTZs) emerges as a key measure for the sustainable recovery and management of overexploited stocks and habitats. To identify appropriate geographical scales for their implementation, it is crucial to understand the spatial connectivity of species and ecosystem functioning during long periods. Therefore, it is necessary to implement robust spatio-temporal multiparametric monitoring procedures, allowing the synchronous collection of biological (i.e., image-based), oceanographic and geochemical data. For this, we developed a spatial cooperative network of fixed (i.e., landers) and docked mobile (i.e., AUVs) platforms with wireless intercommunication capability (i.e., by acoustic modems). This system is designed for intelligent observation monitoring and mapping (i.e., AI-based recognition of species and bioturbation features) over extended periods with real-time, remote supervision and data transmission through the water column to an ASV., Peer Reviewed

To assess conservation efforts and follow the effects of anthropogenic pressures, it is crucial to monitor the ecological status of benthic habitats. Monitoring requires measurements that are made on-site, reproduced over a vast region, and capable of capturing their spatial evolution over time. This calls for the expensively efficient development of tools and protocols that deliver reliable, high-quality data. This article introduces the PLOME multiparametric benthic landers, a new tool and protocol for non-extractively assessing the status of fishes and benthic habitats. By combining independent and wirelessly connected benthic stations, AUVs, and USVs, PLOME creates a spatially adjustable, non-invasive, modular platform. Lander stations will be able to continuously deliver high-rate data while AUVs can provide comprehensive spatial measurements

Deep-sea fishing has been carried out on an industrial scale since the 1950s, and this has had a variety of effects on the environment and its biota. Most benthic species experience a decline in abundance or a constant decline in abundance as a result of direct disturbance of the seafloor, such as its plowing and scraping by hauled nets, with overall impacts on regional biodiversity [1]. Sediment has lost some of its biogenic habitat complexity, and sessile epifauna-provided microhabitat has been destroyed or disrupted [2] and marine protected areas (MPAs) have been widely implemented to address this decline. Marine fish mobility, which is crucial for ecosystem function and is increasingly being researched with acoustic telemetry, has an impact on how well no-take MPAs (i.e., marine reserves) work in terms of protecting and repopulating fish populations [3], [4] Therefore, it is necessary to continuously monitor periodic changes in commercially exploited deep-sea ecosystems in order to gather baseline information, give accurate environmental impact assessments, and derive sound biological indicators for restoration. Using a fixed acoustic ultra-short baseline (USBL) receiver on benthic lander and miniature bidirectional acoustic tags [5], we address three key questions: How far can fish move? Does connectivity exist between adjacent MPAs? Does existing MPA size match the spatial scale of fish movements?, Peer Reviewed

Deep-sea fishing has been carried out on an industrial scale since the 1950s, and this has had a variety of effects on the environment and its biota. Most benthic species experience a decline in abundance or a constant decline in abundance as a result of direct disturbance of the seafloor, such as its plowing and scraping by hauled nets, with overall impacts on regional biodiversity [1]. Sediment has lost some of its biogenic habitat complexity, and sessile epifauna-provided microhabitat has been destroyed or disrupted [2] and marine protected areas (MPAs) have been widely implemented to address this decline. Marine fish mobility, which is crucial for ecosystem function and is increasingly being researched with acoustic telemetry, has an impact on how well no-take MPAs (i.e., marine reserves) work in terms of protecting and repopulating fish populations [3], [4] Therefore, it is necessary to continuously monitor periodic changes in commercially exploited deep-sea ecosystems in order to gather baseline information, give accurate environmental impact assessments, and derive sound biological indicators for restoration. Using a fixed acoustic ultra-short baseline (USBL) receiver on benthic lander and miniature bidirectional acoustic tags [5], we address three key questions: How far can fish move? Does connectivity exist between adjacent MPAs? Does existing MPA size match the spatial scale of fish movements?

The characteristics of a metal supported solid oxide fuel cell on methanol is analysed in as the power generator in a balance of plant consisting out of a reformer, combuster, heaters, pumps, turbines and tubes. The system is reviewed on performance regarding efficiency, power density, fuel utilization and viability for marine applications., Marine Technology

Superyachts are expected to be perfect since the owner pays millions for them, and the worst that could happen is tilting the ship once it floats. The lightweight, including the center of gravity, is essential to know with a high degree of certainty to prevent this. However, the lightweight is already expected in an early design phase, when still a lot is uncertain. When the weight deviates from the initial estimations, it would predominantly lead to unwanted changes in speed and stability. The objective is to research a standardized way of estimating the weight of a superyacht in different stages of the project, including validating the current, improved, and new methods and combining this in a single tool. In the design phase, at the beginning of the project, most weight items or groups are based on comparisons with another yacht. Currently, this is done based on a single ship similar to the new design. Still, a significant improvement will be to compare the new design with multiple yachts, with the possibility for the designer to choose the comparison vessels. The margins can also be researched. Currently, only the starting margin and the production margin at the end are set, but not in between. A guideline should be provided to indicate what margin is expected during each project stage. Also, the complexity level can influence the expected margin, which can all be placed in a table for a clear overview. The center of gravity estimation of the items is done similarly to the weights. The weight distribution of the yacht is currently not included in the weight estimations, but it will be included in the new weight estimation tool. To achieve this, besides the CoG, the length of the items also needs to be noted for the longitudinal weight distribution. With this information, distribution along the ship in the length direction can be calculated per meter. The model can be validated by comparing these early design stage estimation methods with the more det, Marine Technology | Marine Engineering

Although society, governments and the business sector are increasingly demanding that Higher Academic Centers translate their innovative potential into products and services that affect society, little is known or done about the entrepreneurial skills that both lecturers and students need in the context of electronic engineering academic degrees. Inevitably, the fact that some teachers lack certain skill sets will have a negative impact on some students’ professional careers. This article demonstrates a range of initiatives in knowledge transfer which have been carried out over more than 30 years by the university research team making the proposal. Such initiatives have allowed the integration of, not only creative thinking, but also other skills differing from traditional teaching and which can help students to successfully compete for jobs requiring higher qualifications. Following the methodology of a case study within the framework of the Polytechnic University School of Vilanova i la Geltrú (EPSEVG) of the Polytechnic University of Catalonia (UPC), the novelty of the research lies in its focus on the results obtained. In the 1990s, entrepreneurial initiatives encouraged the creation of reference laboratories and the teaching of innovative subjects in the field of virtual instrumentation. Years later, this teaching activity would be complemented by the launch of lines of research/technology transfer. It should be noted that, in its initial stages, this entrepreneurial trajectory was characterized by limited material and human resources, but thanks to the discovery of little-explored areas of activity (niches), opting for working in cooperation networks (sciencetechnology symbiosis), and the entrepreneurial profile of the members of the research team, it has been possible to gain a space in the research/development of marine technologies in the national and European context, as stated in the text. This empirical research has contributed significantly to shaping a, Peer Reviewed, Postprint (published version)

Currently, most ships are designed on the basis of rules and reference ships for which often only the critical structural parts are calculated and designed in detail. This process can result in an over-dimensioned ship with the standard structural outcome of longitudinal stiffeners, transverse stiffeners, and bulkheads with a fixed distance due to ease of manufacturing. With the use of finite element analysis (FEA), the complete structure of a ship is analyzed against prescribed loads, which facilitates the determination of the detailed dimensions of all stiffeners and plates within a reasonable lead time and could result in better engineering in the form of a lighter ship. In addition, the most common structural forms could be optimized by replacing them with unique and optimal shapes. Topology optimization (TO) uses FEA, and it facilitates unique structural shapes. TO generates an optimized material distribution for a set of loads and constraints within a given design domain. The result can be used to inform the design of an improved part. Although the results provide helpful insight, they often cannot be used literally, as they are organic and cannot be manufactured with typical steel shipbuilding methods. The objective of this study is to research the possibility to design the structure of a steel midship with TO where the resulting structural form is manufacturable using steel-cut plates and cost-effective from a shipbuilding perspective. However, constraints that result in a manufacturable structure that can be made cost-effectively from steel-cut plates have not been developed and implemented in TO. To meet the objective, this project was initiated in cooperation with C-Job and the University TU Delft. The methodology was established based on a software comparison followed by an extensive trial and errortesting process. The study was executed in a case study for which the domain concerned the midsection of a 203m offshore vessel named Orion, as TO could resul, Marine Technology

A shift towards electric and hybrid propulsion within the marine sector create new challenges for conventional water jet units manoeuvred by hydraulic systems. The high efficiency in high speed water jet crafts benefit from being powered by electricity but will be compromised by constantly running hydraulic pumps, draining available electric capacity on-board. Wear and tear on hydraulic components are also an environmental contamination hazard, due to high pressure oil and exposed cylinder rods. However, conventional hydraulic power packs with subsystems to manoeuvre water jet unit is a well proven and reliable marine application.Steer-by-wire is not an uncommon subject, as it is frequently used in several industries such as aviation, automotive and offshore. The purpose of the study is to prepare a concept design proposal with CAD-models and drawings of electrically powered manoeuvring system for Marine Jet Powers DRB 750 steering units. The study did a literature study on the topic and qualitative research to fulfil the purpose. A generic product and concept development is conducted and computer aided design is done to present proposed prototype design.Results from the research gave 4 commercially available electrical actuators, all with significantly different functionality from each other resulting in 4 different concepts and thereof 1 prototype proposal integrated in the waterjet unit according to DNV standards.The selected concept in the study will need some further manufacturing configuration and optimisation for a full installation and working prototype., Ett skifte mot elektisk och hybriddrift inom marina fartyg och framdrivningssystem skapar nya utmaningar och möjligheter, även så för höghastighetsfartyg där vattenjet har en fördel i sin karaktäristiska höga effektivitet. Idag manövreras vattenjetsaggregat med hjälp av hydraulik, som många gånger drivs med framdrivningsmaskineriet och/eller med en elektisk pump. Dessa system blir en energitjuv i en elektrisk eller hybridlösning för framdrivningen och så saknar det en naturlig lösning på hur en hydraulisk pump ska drivas. Slitage och skador på hydrauliska system kan även leda till miljöfarliga utsläpp av hydraulolja. Framför allt då det handlar om höga hydrauliska tryck och bland annat kolvstänger som är utsatta för påfrestningar från fartygens yttre miljö. Dock är hydrauliska system väl beprövade och pålitliga i marina miljöer.Styrning med hjälp av elkraft är inget som är nytt, även kallat Steer-by-wire, det har gjorts och används inom många områden så som flygplans-, bil- och offshoreindustrin. Syftet med studien är att skapa ett prototypförslag för elektisk manövrering av Marine Jet Powers vattenjetaggregat DRB 750. För att uppnå detta har en litteraturstudie genomförts och kvalitativ forskning för att samla information och få förståelse för ämnet. En generisk product- och konceptutveckling har använts med hjälp av datorstödd konstruktion för att presentera ett prototypförslag.Det har resulterat i 4 koncept med integrerade lösningar från olika tillverkare, som alla skiljer från varandra i funktionalitet och skulle kunna användas på ett sätt för att uppnå målet. Varav ett koncept som valdes, det vidareutvecklades till ett prototypförslag med skruvförband i vattenjetaggregatet och som även sågs till att uppfylla DNV:s standarder och regler. Det valda konceptet behöver vidare utveckling, integrering och optimering för att kunna installeras och testas i fungerande prototyp.

A brief overview of Hercules Control’s ten years of existence as a marine technology developer. HCTech, with high impact developed products, is not able to bring them to the market. The people involved (research professor and biologist-entrepreneur), their motivations, knowledge and ways of doing things are analyzed. The environment for this initiative is also analyzed from CIS (the mother company from which HCTech arises), from the Uvigo (as an institution and as support to the researcher), from the Administration (as institutional support to ebt’s) and from the bank (as mandatory fnancial support due to the small size of CIS and the need for advances of project funds with the Administration). A refection on the collective aspect of any creation is made. In this case, a lack of entrepreneurial culture in the whole Galician society (administration, fnanciers, businessmen, workers, and even clients) is to be noted., Peer Reviewed

In marine ecosystem management, estimating biomass of marine species is the most significant challenge to control the ecology and biodiversity of a specified marine area and commercial fishery management. Many top-notch researches have been conducted for estimating the biomass of fishes and mammals. Most of the researches followed mainly two methods namely non-acoustics and acoustics techniques to estimate biomass. The non-acoustic technique is a very old terminology and many environmental conditions are to be considered as constant but in the acoustics method it is a much easier and error can be eliminated by different means of transforms. acoustic techniques can be classified in to two types, i.e., active acoustic techniques, and passive acoustic techniques. In this paper, we have reviewed the major acoustic and non-acoustic techniques for estimating biomass of fish and mammals. At the same time, performance analysis among these techniques has been discussed here. An introduction to the diversity in biomass estimation techniques of fishes and mammals is the aim of our investigation.

The rapid development of autonomous systems and Information and Communications Technologies (ICT) create new opportunities for maritime activities. Existing autonomous systems are becoming more powerful and utilise the capabilities of several types of devices such as Autonomous Underwater Vehicles (AUVs), Unmanned Surface Vehicles (USVs) - sometimes referred as Autonomous Surface Vehicles (ASVs) -, Unmanned Aerial Vehicles (UAVs), moored and drifting systems and, recently emerging, autonomous vessels. Their importance in providing new services in maritime environments is undeniable and the opportunity for coordinated and interconnected operations is clear. However, continuous wide integration of various technologies in maritime environments still faces many challenges. Operations may take place in remote locations, so that dependence on third-party infrastructures such as satellite communication or terrestrial communication systems must be expected. The reliability, performance, availability, and cost of such systems are important issues that need to be tackled. This work reviews the major advancements on state-of-the-art autonomous maritime vehicles and systems, which are used in several different scenarios, from scientific research to transportation. Moreover, the paper highlights how available technologies can be composed in order to efficiently and effectively operate in maritime environments. Highlights of the trade-off between autonomy and communication requirements are provided and followed by an overview of promising communication and networking technologies that could encourage the integration of autonomous systems in maritime scenarios., QC 20190918

The crises of global warming, air pollution, acid rain and the running out of oil make the investigation into alternative fuel technologies crucial. New technologies are being investigated on a global scale in an attempt to address these problems. This thesis investigates the use of hydrogen-diesel dual-fuel engines and fuel cells. The economic feasibility includes the comparison of these energy converters with more conventional alternatives. The storage of alternative fuels, the reforming of hydrogen carriers or the inclusion of carbon capture systems are some of the aspects considered in the analysis., Marine Technology | Ship Design, Production and Operations

Carbon dioxide emission into the earth’s atmosphere by maritime activities are a concern for the people within and outside the industry. This is because of the environmental impacts that are caused by these greenhouse gas emissions which changes the very chemistry of this planet. These impacts can be mitigated by reducing the CO2 emissions which can be achieved by several design and/or operational means. Waste heat recovery (WHR) technology is one such means that is capable of reducing emissions. This is achieved by improving the overall fuel efficiency of marine engines which reduces the fuel consumption of the vessel. This improvement is realised by harnessing the heat energy that is expelled by the engine through waste heat sources such as exhaust gas, etc. Organic Rankine cycle (ORC) is one of many WHR technologies that is capable of harnessing that waste heat energy from the fuel which cannot be utilised by the engine operation alone. ORC as a WHR system (WHRS) is widely implemented in land based applications due to its fluid choice flexibility, plant simplicity and net efficiency. However, it is rather new to the maritime industry because WHRS on-board ships are predominantly based on steam Rankine cycle or turbo-compounding. These systems have their own advantages but ORC-WHRS may outweigh them in certain applications on-board ships. This is especially for electrical power generation from low and medium temperature waste heat sources. However, ORC in marine application encounters challenges unlike seen in land based applications. These challenges are caused by the physical & geometrical constraints, operational profile of the vessel or uncertainties caused at sea. In this thesis, the implementation of ORC-WHRS to marine engines for exhaust gas is investigated and studied to understand how such an application can be beneficial. Unlike steam Rankine cycle, an ORC system has flexibility in choosing an organic fluid that is suitable based on the app, Marine Technology | Ship Design, Production and Operations

The Macaronesia is a vast area playing a key role in the East boundary of the Central North-Atlantic ocean-circulation system. Despite a significant research activity in ocean monitoring for decades using a wide range of observing systems and methodologies, the area is still under-sampled, mainly due access and coverage constrains, as well as the observation sustainability. Ocean gliders offer a new approach in terms of capacity and sustainability, allowing undertake ocean-monitoring in spatiotemporal scales hitherto unavailable. The present work shows preliminary results from the latest mission with buoyancy-driven and surface ocean gliders in the area, whose main goal focuses on to improve and expand ocean observation capabilities strengthening glider endurance lines between archipelagos, as part of the global ocean-observation strategy conducted by the Marine & Maritime Network (R3M), as regional contribution directly aligned with European and international initiatives and strategies in the North Atlantic basin., Peer Reviewed

Due to the increased social importance and regulations on shipping emissions, effort must be made by shipowners, operators and naval architects to reduce the amount of air emissions from ships. A large set of emission control methods exists, but compatibility and interaction issues complicate their implementation. This thesis contains a decision-making method tailor-made to the case of Seatrade. The decision-making method makes a cost comparison of different emission compliance methods for an arbitrarily ship, making use of the NPV. Case studies are performed to get an indication of the promising emission compliance methods for the Seatrade fleet., Marine Technology | Ship Design, Production and Operations

This report describes the first Lloyd’s Register Foundation Safety Grand Challenge and details how a collaborative, cross disciplinary design research and teaching approach can provide a platform for a broad variety of participants to develop projects in a complex design safety environment, encourage collaboration and industrial involvement in design education and contribute to a balance between technological developments and the needs of people in the future. The Royal College of Art, generously supported by the Lloyd’s Register Foundation and working with a group of industry stakeholders, investigated two major areas of risk within the maritime context: Sea Safe transfers from ship to ship, and making the Thames the safest city river by the year 2030. In a four month project, thirty-two postgraduate participants from eleven disciplines and six researcher-tutors at the Royal College of Art worked together to tackle these complex and wicked design challenges using a number of novel design methods. With a focus on finding cutting-edge innovative design solutions that would reduce risk on the ship to ship transfer and on increasing safety on the River Thames, the research project explored a wide range of approaches that encouraged collaboration, innovation and risk taking in design research practice. The different cultures, practices and knowledge bases led to an array of eight pioneering design solutions, ranging from product-focused innovations through to systemic solutions, material innovations and educational strategies. This report makes a case for the culture of design engaging with risk on water in the context of the wicked problems (Rittel & Webber, 1973; Buchanan, 1992) we identified, the methods and techniques used to tackle these challenges, how cross disciplinary projects can lead to novel insights, and how design education can be used to engage with industry and users to bridge the gap between technological innovation and user needs. Our conclusions suppo

Accurate cost estimations are important for ship production companies such as Royal IHC. The research discussed is based on a feasibility study for a CBR cost estimation method. The current cost estimation method at IHC is a top-down price-to-win analogy cost estimation. This method uses mainly the weight of the ship as an input variable for the estimation. A problem with using only weight is that the actual work performed on a section is left out of the estimation as well as other cost drivers. Another problem occurring is the current estimation method being divided into three phases, with lacking evaluation, optimization and feedback possible. This research discusses two new cost estimation methods. The statistical method is a parametric cost estimation method, that uses equations with the main cost drivers. The graph database method uses the CBR theory as a basis for cost estimations. Problem solving is done by using a solution from an old ship and reusing this solution for a new ship. The graph database stores detailed information about the work performed on the ship and the main cost drivers. The qualitative and quantitative analyses showed that usingmultiple cost drivers and the work performed on a section creates more accurate cost estimations. With a solution as the graph database method also the possibilities of evaluation and process optimizations are broader., Marine Technology | Ship Production

The abdominal segment deformity disease (ASDD) is a new shrimp disease reported only in cultured Penaeus vannamei in Thailand. Shrimp with ASDD have deformed abdominal segment, jagged gut line and bumpy surfaces. Similar signs were observed in cultured P. indicus in the Philippines. However, aside from the signs described for ASDD, some P. indicus showing abdominal segment deformity syndrome (ASDS) had more severe deformities up to the extent that the number of body segments was reduced due to fusion. Shrimp with fused body segment deformity (FBSD) had four instead of five pairs of legs. To account the prevalence of the deformities in P. indicus, shrimp were classified into grossly normal shrimp (NS), shrimp with abdominal segment deformity syndrome (ASDS) and shrimp with fused segments (FBSD). Out of the shrimp sampled, 83.4 ± 5.4% was NS, 10.9 ± 6.2% was ASDS and 5.7 ± 3.0% was FBSD. Morphometric characteristics of the shrimp were measured. There was no significant difference in body weight (BW) among male and female NS, ASDS and FBSD. In both sexes, total length (TL) of FBSD was significantly shorter compared to NS and ASDS. Shrimp samples were also screened to be negative for known infectious viral diseases including white spot syndrome virus (WSSV), infectious hypodermal and haematopoietic necrosis virus (IHHNV), infectious myonecrosis virus (IMNV), P. vannamei nodavirus (PvNV), Macrobrachium rosenbergii nodavirus (MrNV) and Taura syndrome virus (TSV). Occurrence of ASDS and FBSD in post-larvae (PL) produced from captive and wild spawners were also determined. Based on a tank experiment, no significant difference was detected between the percentages of ASDS in PL produced from wild or captive spawners but FBSD was only noted in PL produced from the latter. Deformities generally did not affect the size of P. indicus except for the reduced length of shrimp with FBSD which when coupled with missing pleopods could lead to major economic loss for shrimp farmers if n

Oceanographic sensors are accurate and reliable but very expensive. We have developed and calibrated a cheap temperature sensor with a good cost/ accuracy ratio., Peer Reviewed

The IEEE Robotics and Automation Society (RAS) Marine Robotics Technical Committee (MRTC) was first established in 2008 following the dismissal of the Underwater Robotics Technical Committee in spring 2008. The goal of the MRTC is to foster research on robots and intelligent systems that extend the human capabilities in marine environments and to promote maritime robotic applications important to science, industry, and defense. The TC organizes conferences, workshops, and special issues that bring marine robotics research to the forefront of the broader robotics community. The TC also introduces its members to the latest development of marine robotics through Web sites and online social media. © 1994-2011 IEEE.

At a study site on the north west coast of England, concrete revetment armour that has been power washed on a regular basis has been monitored for surface changes over three years. Three tests have been utilised. Replication was employed as a means of measuring surface roughness of the concrete surfaces and lays the foundation for the development of a new non-destructive testing (NDT) method for concrete surface analysis. Surface roughness doubled from S1229μm, increasing to Sa24.67μm in three years. A Schmidt/rebound hammer test has also been used throughout the research to evaluate the surface hardness of the concrete, and has demonstrated a significant deterioration in the concrete surface after three years. Ultrasonic pulse velocity (UPV) testing, used to measure the sound velocity of the concrete, has also implied degradation

This thesis considers the design, optimization, and control of a coupled cylindrical floater and permanent magnet linear generator for wave-energy conversion. The investigation begins with the construction of the time-domain equation of motion for a generic floating body. The construction of a physical cylindrical floater is followed by a description of the experiments completed to verify free-motion and wave-exciting force predictions. The time-domain equation of motion was compared against experiments where it was found that corrective terms needed to be added due to the presence of viscosity. Initial low motion amplitudes lead to evaluation of the hydrodynamic performance between a floater with a flat and rounded-hemispherical bottom. Experimental results demonstrated that motion amplitudes can be over predicted by a factor of 2 when neglecting the effects of viscosity.Second, modifications to the design, fabrication process, and material of a permanent magnet linear generator (PMLG) will be discussed with the aim of increasing both power output and mechanical-to-electrical conversion efficiency. In order to evaluate the performance of the power-take-off unit a dry-bench test was completed which consisted of driving the armature of the PMLG at various frequencies with a fixed motion amplitude. The force signature from the bench test was used to extract the spring, damping, and inertia force coefficients due to the influence of the PMLG. The force coefficients were obtained for various speeds, resistive loads, and magnet coil gap widths. The floater equation of motion was modified to accommodate the influence of the PMLG to predict the coupled system performance. As the damping coefficient was the dominant contribution to the PMLG reaction force, the optimum non time-varying damping values were presented for all frequencies, recovering the well known impedance matching at the coupled resonance frequency. Model-scale tests of the coupled floater-generator system we

The last decade has seen a step change in our efforts to monitor the state of the worlds' oceans. This has at least partly been driven by a need to better understand the role of the oceans in climatological processes. This unmet need also stimulated the development of an array of new technology; principally in the form of unmanned floats and gliders and more comprehensive fixed mooring array systems. This instrumentation has underpinned the delivery of time series of data that are used to update a suite of indicators. However, despite the step change in observing efforts, the vast majority of this effort has been directed towards the monitoring and indicators of physical processes in the oceans. Although these physical processes play a central role in global climate dynamics, from a marine resource and systems management perspective the key ecosystem goods and services are mostly biological in nature. It is therefore argued here that despite the recent advances in efforts to observe the marine environment, there remains a large unmet need in monitoring and observing, and hence establishing time series of indicators of the key biological and ecological stocks, flows and processes in the oceans.

The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given. © 2011 Elsevier B.V. All rights reserved.

For a complete understanding of a wave energy conversion device, it is important to know how the proposed device moves in the water, how this motion can be measured, and to what extent the motion can be predicted or simulated. The magnitude and character of the motion has impacts on engineering issues and optimization of control parameters, as well as the theoretical understanding of the system. This paper presents real sea measurements of buoy motion and translator motion fora wave energy system using a linear generator. Buoy motion has been measured using two different systems: a land-based optical system and a buoy-based accelerometer system. The data have been compared to simulations from a Simulink model for the entire system. The two real sea measurements of buoy motion have been found to correlate well in the vertical direction, where the measured range of motion and the standard deviation of the position distributions differed with 3 and 4 cm, respectively. The difference in the horizontal direction ismore substantial. The main reason for this is that the buoy rotation about its axis of symmetry was not measured. However, used together the two systems give a good understanding of buoy motion. In a first comparison, the simulations show good agreement with the measured motion for both translator and buoy.

On March 13th, 2006, the Division of Electricity at Uppsala University deployed its first wave energy converter, L1, in the ocean southwest of Lysekil. L1 consisted of a buoy at the surface, connected through a line to a linear generator on the seabed. Since the deployment, continuous investigations of how L1 works in the waves have been conducted, and several additional wave energy converters have been deployed. This thesis is based on ten publications, which focus on different aspects of the interaction between wave, buoy, and generator. In order to evaluate different measurement systems, the motion of the buoy was measured optically and using accelerometers, and compared to measurements of the motion of the movable part of the generator - the translator. These measurements were found to correlate well. Simulations of buoy and translator motion were found to match the measured values. The variation of performance of L1 with changing water levels, wave heights, and spectral shapes was also investigated. Performance is here defined as the ratio of absorbed power to incoming power. It was found that the performance decreases for large wave heights. This is in accordance with the theoretical predictions, since the area for which the stator and the translator overlap decreases for large translator motions. Shifting water levels were predicted to have the same effect, but this could not be seen as clearly. The width of the wave energy spectrum has been proposed by some as a factor that also affects the performance of a wave energy converter, for a set wave height and period. Therefore the relation between performance and several different parameters for spectral width was investigated. It was found that some of the parameters were in fact correlated to performance, but that the correlation was not very strong. As a background on ocean measurements in wave energy, a thorough literature review was conducted. It turns out that the Lysekil project is one of quite few projec

The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given. (C) 2011 Elsevier B.V. All rights reserved.

The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given. © 2011 Elsevier B.V. All rights reserved., 0, SCOPUS: ar.j, info:eu-repo/semantics/published

The International Submarine Race (ISR) presents opportunities to students to achieve excellence in areas of marine technology and ocean engineering. The quality of the technical expertise of our young students tends to be gradually decreasing. There exist too many distractions like peers pressure, expertise in athletic endeavors, an excess of time and money, or apathy. There also exists the need to strengthen and enhance the scientific and technical literacy of our students. If there is excitement in an activity, the student becomes motivated and will tend to exert his/her best efforts. Also, if there is a challenge to excel, the motivation factor increases. The ISR was conceived as a "hook" to interest talented and motivated students to become involved in marine technology and ocean engineering. The ISR is an engineering design competition open to high schools, colleges, and university students, and individuals. The focus of the ISR is on the engineering principles and technologies involved in the design and operation of a human- powered submarine. The paper will address how the ISR provides the stimulus for engineering education that attracts favorable public and academic attention. Examples of some of the successes achieved to date will be presented., See also ADM002176. Presented at the MTS/IEEE Oceans 2008 Conference and Exhibition held in Quebec City, Canada on 15-18 September 2008. U.S. Government or Federal Rights License.

The Glider Coordinated Control System (GCCS) uses a detailed glider model for prediction and a simple particle model for planning to steer a fleet of underwater gliders to a set of coordinated trajectories. The GCCS also serves as a simulation testbed for the design and evaluation of multivehicle control laws. In this brief, we describe the GCCS and present experimental results for a virtual deployment in Monterey Bay, CA and a real deployment in Buzzards Bay, MA. © 2008 IEEE.

Having already shown its potential of deriving the vector fields representing the ocean-surface advection from sequential 1.1-km-resolution local area coverage (LAC) Advanced Very High Resolution Radiometer (AVHRR) images, the maximum cross-correlation (MCC) technique here is applied to four 4.4-km-resolution global area coverage (GAC) AVHRR images. The resulting three vector fields are compared to the vector fields obtained from the LAC imagery corresponding to the same satellite passages. To quantify the reduction in accuracy inevitable when applying the method to the lower resolution imagery, the LAC vector fields were assumed to be error free. The deviation of the GAC vectors from the LAC vectors is expressed as percentage errors of the signal variance of meridional u and zonal v velocity components, and they are 16%/30%, respectively, for the best case and 62%/117% and 92%/111% for the other two cases. These results indicate that, in its present state, the GAC data do not allow the MCC technique to extract reliable current-vector information from it.

We calibrated a sound velocimeter to a precision of +/- 0.034 m/s using Del Grosso's sound-speed equation for seawater at temperatures of 2, 7.2, 11.7, and 18 degrees C in a tank of seawater of salinity 33.95 at one atmosphere. The sound velocimeter measures the time-of-flight of a 4-MHz acoustic pulse over a 20-cm path by adjusting the carrier frequency within a 70-kHz band until the pulse and its echo are inphase. We used the adjustable carrier frequency to determine the internal timing characteristics of the sound velocimeter to nanosecond precision. Similarly, sound-speed measurements at four different temperatures determined the acoustic pathlength to micrometer precision. The velocimeter was deployed in the ocean from the surface to 4500 dbar alongside conductivity, temperature, and pressure sensors (CTD). We demonstrated agreement of +/- 0.05 m/s (three parts in 10(5))-with CTD-derived sound speed using Del Grosso's seawater equation from 500 to 4500 dbar after removing a bias and a trend.

A significant example of technological spin-off from the GEOSTAR project is the special-purpose instrumented module, based on the deep-sea ROV MODUS, developed in the framework of the EU-sponsored project BIODEEP. The goal to be achieved has been defined as the exploration of the deep hypersaline anoxic basins of the Eastern Mediterranean Sea through real-time video images. measurements and accurate video-guided sampling at water depths well exceeding 3000 m. Due to their peculiar characteristics, these basins are one of the most extreme environments on Earth and represent a site of utmost interest for their geochemical and microbial resources. The paper presents the strategies and the main results achieved during the two cruises carried out within the BIODEEP project.

The quick evolution of fish farming in Europe, and its development towards the open sea needs suitable farming tools. These tools must withstand the difficult sea states, but they must be easy to use, well adapted to the fish farming and not too much expensive. This book helps the design of such tools. It defines the solicitations of the sea on all the structures, and presents rules and methods to control these solicitations. Here, a structure is composed of a rearing support, a mooring system and equipments. This book describes these components, class them and gives lists of providers. The rearing support can be a cage, a group of cages or a boat. The support can float or to be submersible. The mooring system can be made up ropes, chains, anchors, concrete blocks, floats, clump weights... Equipments are all these tools as manual/automatic feeders, graders, aerators, sensors, fish pumps, net washers, antifouling, nets, net cleaners, counters, scales, work boats... In this book the environment of the fish farming structure is: -- the atmosphere, which takes into account the wind, the corrosion and the dissolved gases, -- the sea water, which is the main vehicle of solicitations, as wave and current forces, tide effects or corrosion, -- the sea bottom, where the structure is moored through the foundations of the mooring system., L'évolution rapide de la pisciculture marine en Europe et son extension vers le large nécessitent une adaptation des matériels d'élevage. Ils doivent résister aux difficiles conditions météo-océaniques tout en restant pratiques d'utilisation, adaptés aux conditions d'élevage des poissons et d'un coût d'achat et de fonctionnement limité. Le présent ouvrage aide à la conception de telles structures d'élevage. Il définit les sollicitations sur ces équipements et propose des régies et des méthodes pour contrôler leurs effets. Une structure se compose d'un support, d'un amarrage et d'équipements. L'ouvrage les décrit, les classe et propose également des listes de fournisseurs. Dans cet ouvrage l'environnement est représenté par : - l'atmosphère qui prend en compte le vent, la corrosion et les gaz dissous dans l'eau ; - l'eau de mer, vecteur principal des sollicitations, tels les efforts de houle ou de courant ou encore la corrosion ; - le fond, sur lequel est amarrée la structure.

Marine capture fisheries in Jamaica is primarily artisanal in nature ansd is conducted maiinly by fishermen operating from canoes. Approximately 95% of these fishermen operate on the coastal shelf and its associated banks. The commercial species harvested comprise bottom-dwelling, coral reef species and free swimming species of finfish. Other fishery resources of commercial value include marine shrimp, conch and lobsters. Catch statistics are not available for all species, but the Department of Fisheries reports a slight decline in fishery production with production decreasing from 16 milion lbs in 1990, despite the fact that fishing efforts have doubled. Over this period the number of registered fishermen has grown from 12 000 to 16 000, al of whom are engaged in full-time fishing. There arealso part-time fishermen who are not registered. The decline in fish catch is accompanied by a decrease in fish size and quality, suggesting that the fisheries are under pressure and have already exceeded optimum production in relation to vailable resources. As a result the economic returns to fishermen are declining. There are also other problems, such as high incidence of conflicts among fishermen at sea, the high cost of purchasing boats, outboard engine fuel, and equipment, with together with the dangers involved in fishing offshore (piracy, and praedial larceny) create serious social ans economic difficulties for fishermen. Notwithstanding, there is an apparent move on the part of the fishermen to leave the industryor to seek alternative forms of employment. In fact, the Department ofFisheries reports that it is still reciving applications for new licences to operate fishing boats. This is probably due to the fact that where the basis of a community is fishing, it becomes difficult to introduce alternative forms of employment, such as cottage industries, village crafts and other trades. In 1987 the Jamaica Department of Fisheries prepared a Management plan which proposed se, Les pêcheries de captage marin en Jamaïque sont principalement de nature artisanale et elles sont dirigées principalement par les pêcheurs qui travaillent depuis des canoës. Environ 95 % de ces pêcheurs travaillent sur la plaine côtière et ses bancs associés. Les espèces commerciales récoltées comprennent les espèces benthiques, les espèces de corail et les espèces de poisson marin de nage libre. D'autres ressources de pêcheries de valeur commerciale comprennent la crevette, la conque et le homard. Les statistiques des pêches ne sont pas disponibles pour toutes les espèces, mais le Département des Pêcheries fait état d'une légère réduction de production de pêcheries, la production se réduisant de 16 millions de livres en 1990, en dépit du fait que les efforts de la pêche ont doublé. Sur cette période le nombre de pêcheurs inscrits a augmenté de 12 000 à 16 000, dont tous sont occupés à plein temps à la pêche. Il y a aussi des pêcheurs à mi-temps qui ne sont pas inscrits. La réduction des pêches est accompagnée d'une réduction de la taille et la qualité des poissons, ce qui implique que les pêcheries sont sous pression et qu'elles ont déjà dépassé la production optimum par rapport aux ressources disponibles. En conséquence, les rendements pour les pêcheurs sont en baisse. Il y a aussi d'autres problèmes, tels qu'un taux élevé de conflits entre les pêcheurs en mer, le coût élevé pour acheter les bateaux, le combustible pour les moteurs hors-bord, et le matériel, ainsi que les dangers impliqués dans la pêche offshore (le piratage, et le vol prédial) ont créé de graves problèmes sociaux et économiques pour les pêcheurs. Néanmoins, il y a une tendance évidente chez les pêcheurs de quitter l'industrie ou de chercher du travail dans d'autres domaines. En fait, le Département des Pêcheries signale qu'il continue de recevoir des demandes de nouveaux permis pour opérer les bateaux de pêche. Ceci est probablement attribuable au fait que là où la base d'une communauté est la pê

Underwater vehicles are used to discover the wrecks, and the author deals with the using of the new marine technology in the archaeology.

In remote control, the master element which the user operates looks for practical and historical reasons like the slave arm and therefore features a series architecture, with a few drawbacks in terms of mass, dimensions, rigidity and mechanical complexity. To remedy these defects, we are now introducing a new master element with parallel kinematics. This syntactor, derived from Steward's manipulators, has six degrees of freedom and comprises six motor-driven links arranged on a fixed plate (the base) and a moving plate on which a 6-axis force transducer and a handle are mounted. The device is made artificially free along a few or all axes by means of a hybrid position/force control software which translates the wrench of forces applied by the operator on the handle into displacement for the syntactor, as well as for the slave arm. The operator can thus control the syntactor and the slave arm on free moves, or forced moves, such as drilling, cutting. When the slave is also equipped with a 6-axis force transducer in its terminal part, the operational wrench of forces is then sent to the master in order to implement a two-direction remote control system with known modes, such as weight suppression, homothetic forces.

Sediment instability appears to be important as a part of global sedimentary budget. Among the various types of sedimentary instabilities, submarine slides are probably the most spectacular and the hardest to study and predict, although their consequences on human and industrial marine activities can be dramatic. IFREMER is conducting a research project on this topic. An area off Nice (France) has been particularly studied because of its recent activity. Mapping and instability area detection have been carried out. With the possibility of direct interactive observation and highly accurate submarine in -situ operation, the submersible is an extremely efficient tool for sediment studies, but diving purposes have to be precisely defined to provide useful information. In the future, the submersible will still be a major key-tool to study marine sediments, although new systems such as video-ROV will be used complementarily. The present evolution of scientific purposes aiming at a better quantitative comprehension of geological processes might broaden the range of submersible applications in the near future.

A conceptually new, modularly designed exploration system for the deep sea (600 m) has been constructed and tested. In its base unit, different soil sampling tools can be integrated. These are, for the time being, a drill core barrel with 0 48 mm iD and a length of 500 mm for rocky basements as a box corer for softer soils as well as an orange peel grab. Towed along via a coaxial cable from a research vessel, the system is TV-guided and can be actively positioned by means of 2 thrusters in order to be lowered precisely and horizontally levelled on the seafloor. The total system is operated by the help of an onboard computer and may be controlled by sensor displays and operation messages. Microprocessors control the underwater unit which is partially automated. Possibilities for further potential developments are presented. The system yields prospective new exploration methods.

This system is composed of a high accuracy hydraulic manipulator arm with 6 degrees of freedom, for high loads (2000 daN), using ultrasound proximetry and contact force measurement data to carry out the subsea connection of bottom oil wells. An expert system controls the connection phases and generates the sequences of commands to be executed by the robot. The safety systems and failure modes are also taken into account. A graphic operator station provides easy control. Each connection phase generates a graphic representation of the robot status and all the proprioceptive and exteroceptive sensors. The control/command system, although it is designed to carry out a subsea connection by means of a manipulator arm, can be adapted to any type of process. For example, it will soon be used to control the decoking process in an oil refinery.

Autonomous Underwater Vehicles, also called "free-swimming vehicles" are self propelled bodies, equipped with their own energy package and with no solid communication link with the surface. At the beginning of the 90s, a renewed interest from the Underwater Intervention Community for autonomous vehicles and quite a number of new projects were announced or started. The present paper aims at presenting an updated State of the Art on the development of autonomous vehicles. It addresses the following points: A brief historical review presents some existing systems and uses. The French experience, in particular, allows to position the potential, and complementary contribution of autonomous vehicles, in a range of various operational systems. A short review of the main developments in the world demonstrates the particular interest for underwater robotics. An analysis of the operational aspects of these various projects leads to a distribution of the different concepts into main classes of mission profiles.

Detecting and localizing nuclear blasts was an essential stimulus of the actions undertaken in the 1960's to emplace seismological observatories on the seafloor. The plate-tectonic theory, in which the oceanic areas play a major role, greatly accelerated the evolution of modern oceanology. The contribution of Ifremer's department of Marine Geosciences, in helping to advance this area of research, has been significant since 1972. The need for refraction studies to explore the deep structure of the margins and ocean-continent transition zones led us to design a deep-sea Ocean Bottom Seismograph (OBS) MK I in 1975, rated to 6,000 metres depth. This system introduced, for the first time, the concept of "isolated seismic sensors". This principle was adopted later on by other instrument designers. The OBS MK II was constructed in 1978, namely to study interferences between the instrument and the "isolated seismic sensors" as well as to test, under real operating conditions, an instrumental design which makes use of the "long inverted pendulum" concept. A series of four instruments were built, which also incorporated some innovative features in OBS technology, such as high density digital recording. A new system, the Ocean Bottom Seismic System (OBSS), was designed in August 1990 aiming at the construction of a variety of instruments from basic modules.

The Nautile submersible is used to observe the underwater geological structures and to conduct geological sampling in deep water. But it is not sufficient because it is not possible to measure the faults in the oceanic rifts.

The mechanical behaviour of sediments is usually studied from laboratory core analyses which do not take into account the real state of in-situ stresses. Therefore, the aimed purpose is presently to determine the in-situ geotechnical properties which mainly depend on the relationship between fine-grained particles and intergranular fluids. At IFREMER, these achievements have been pursued in the framework of 2 scientific program: "Nodules and Sedimentary Processes and Instability on Slopes, for which surficial measurements were conducted on selected seafloor targets usually pre-defined from high resolution geophysical data." 2 kinds of instrumentation were developed in correlation to 2 different strategies of handling at sea. There is the instrumentation of the submersible "Le Nautile" equipped with a vane shear device, which enabled us to measure for the 1st time the in-situ undrained shear strength of pelagic sediments in the nodule environment. The possibility of accurately choosing on the seafloor the testing sites by means of a submersible, enable us to achieve this spectacular operation of ground-truthing. The other set of instrumentation is an autonomous equipped frame tethered by a cable. It is a supported rig which can be handled by any customary oceanographic vessel and is designed to penetrate the seafloor up to 2 m with a piezo-cone.

Responsible for large exchanges between the Ocean and the Lithosphere, oceanic hydrothermalism covers wide scientific domains, from the ocean chemistry to metallogeny. The exploration covers all scales, from the hydrothermal site to the Mid-oceanic ridge system. Modern bathymetry and imagery are required. Physical and chemical anomalies created in the ocean are used to detect and map its distribution. A specific effort in the field of ROV (Remote Operated Vehicle) is needed to acquire data at the corresponding working scale.

On the bathyal slope for continental margins, steep and rocky substrates punctuated with cliffs and collapsing zones are frequently found. As survey and sampling with the classical technics from the sea surface is practically impossible in such an environment, in situ exploration with a submersible allows significant advances in ecology, with implications in paleoenvironment reconstruction. Mixing of material from shallow-water and deep-sea origins into bathyal sedimentation suggests that the so-called "fossil assemblages of outer platform" were frequently misinterpreted. Dense populations of animals closely related to fossil groups which were only considered as relict of the Past ("living fossils") and previously interpreted as shallow-water inhabitants during geological times can be discovered living in such bathyal communities. The role of bathyal ecological niches during global bioevents brings a new vision of the history of life in the Ocean through geological time and has to be further investigated. Examples from cruises monitoring the diving saucer Cyana (SP 3000) in the Bay of Biscay and off New Caledonia are given.