2014 Oceans - St. John's最新文献

{"title":"A novel method for surface to subsea localization utilizing a modified hough transform","authors":"Valentina Zeiger, S. Badri-Hoeher","doi":"10.1109/OCEANS.2014.7003214","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003214","url":null,"abstract":"A new approach for acoustic localization of a fixed subsea transponder using a surface vessel equipped with a transceiver and global positioning system (GPS) based on a modified Hough transform (MHT) is presented. The MHT developed in this work is used to determine the latitude and longitude coordinates of a transponder utilizing acoustic range and GPS data gathered by the surface vessel while traveling a particular route. Various survey scenarios for a single seabed transponder have been simulated and studied considering both, accurate and inaccurate ranging, as well as realistic conditions such as different route lengths and inexactly geometrical routes (inter alia ellipse-shaped routes). The MHT-based localization approach may particularly find use in the survey of long baseline transponders. The fixed seabed transponders are provided to enable exploration tasks by acoustic networking in various fields, from science and research covering the seas and oceans (e.g. oceanography, marine biology and geology) to industrial use (e.g. exploration of deep-sea resources and minerals, monitoring of offshore constructions). The simulation results demonstrate that the proposed approach can localize the transponder unambiguously and precisely for accurate ranging. Concerning the impact of uniform ranging uncertainties, e.g. arising from spatio-temporally coherent sound speed variations, it can be concluded that full circle and ellipse routes enable a precise estimate while half and quarter circle as well as ellipse routes enable a positioning accuracy within the millimeter range. In the presence of noisy range measurements, e.g. impacted by GPS errors, the approach can provide root mean squared errors from less than 5 mm to 5 m for ranging with a standard deviation of 7.5 mm and 7.5 m, respectively. The proposed positioning approach outperforms the least-squares estimation when shortened survey routes such as half and quarter ellipse are considered. These route forms accelerate the data gathering process, which are motivated by the reduction of the vessel time and cost for the transponder survey.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130544062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Towards standardization of the measurement of underwater noise radiated from marine pile-driving","authors":"P. Theobald, S. Robinson, T. Pangerc, P. Lepper","doi":"10.1109/OCEANS.2014.7003200","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003200","url":null,"abstract":"Pile-driving of marine foundations can radiate substantial levels of low-frequency impulsive noise into the water column, which given the right acoustic propagation environment conditions can propagate over large distances. Concern over the potential for impact on marine fauna often results in a regulatory requirement to measure the radiated noise level over distances which may extend tens of kilometres. Furthermore, if the transmission loss is to be established or validated it would be necessary to measure as a function of range at a number of positions. Because of the variation in hammer energy during the pile-driving activity, particularly if a soft-start is employed, it is also desirable to perform the measurement independent of distance for the duration of the pile-driving operation. A number of others factors will also influence the noise radiated into the water column, including the water depth (exposing a different amount of the surface area of the pile), the seabed properties, the penetration depth into the seabed by the pile, the pile dimensions, and the hammer energy. Importantly, some of these factors may change during pile-driving of an individual pile, for example tidal variation and sediment penetration, and this means that the acoustic output is likely to change during the driving of a specific pile. A method for the measurement of this underwater noise, that is generally in relatively shallow water, which considers both the spatial and temporal variation of the sound field is described. The method includes a combination of fixed autonomous recorders and vessel based hydrophone deployments. The paper describes the activities within the International Organization for Standardization (ISO), Technical Committee 43, Sub-Committee 3, Working Group 3 to produce an international standards document to define the appropriate measurement methodology, which should be followed when measuring underwater noise radiated from marine pile-driving.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126694425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Iceberg severity off the east coast of North America in relation to upstream sea ice variability: An update","authors":"J. Marko, D. Fissel, Mar Martinez de Saavedra Alvarez, E. Ross, R. Kerr","doi":"10.1109/OCEANS.2014.7003128","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003128","url":null,"abstract":"Earlier examination of strong correlations between mid-winter spatial extents in Davis Strait and large annual variations in the estimated numbers of icebergs passing south of 48°N motivated detailed studies of the origins of variability in iceberg numbers was conducted over twenty years ago [1]. This work established the critical role played by the processes that control the cyclonic movement of the icebergs from their primary West Greenland calving ground to the northern perimeter of Baffin Bay and, subsequently past the coastal shelves of North America. It was demonstrated that the effectiveness of these processes and year to year variations in their timing tended to overwhelm interannual variations in Greenland iceberg calving rates. A major connection between such fluxes and upstream ice extent was established through the effectiveness of extensive pack ice in lowering deterioration and melt rates of freely drifting icebergs during the last, late winter through early summer, segments of their drift trajectories. This role is exercised through the effectiveness of sea ice in lowering the local water temperature and reducing sea state parameters which essentially determine iceberg lifetime in these segments. Comparisons between historical International Ice Patrol (IIP) records of annual south of 48N iceberg numbers and a shorter record (post-1960's) of sea ice extents indicated strong correlations between the former and the January spatial extent of ice in Baffin Bay and Davis Strait north of 67N. Measures of this extent, designated as the Davis Strait ice index (DSII) were subsequently used on their own or with modifications as a basis for early season assessments and apportionments of resources by the IIP and others with interests in East Coast navigation. The iceberg severity off Newfoundland is revisited in the light of several major efforts to document and reorganize East Coast iceberg data-taking and analyses as well as the availability of, roughly, 20 more years of higher quality sea ice and iceberg data. The updated and extended analysis includes assessing impacts of suspected over-counting in early iceberg surveys and access to improved Canadian Ice Service (CIS) digital ice chart data, available from 1971 to the present, which allows better resolution of the sea ice data in marine areas upstream of 48N both in terms of areas of interest and in time. Examination of the 1971-2014 sea ice concentrations in Davis Strait for mid-January reveal that the post 2000 ice extents are consistent with the iceberg numbers being lower than those observed and inferred from the 1980-1999 sea ice concentrations. This extended analysis also discriminates between sea ice types, in particular first year ice vs. the thinner new to young ice categories for regions with three-tenths or more in ice concentration in the DSSII area of interest.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123901054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A mission programming system for an autonomous sailboat","authors":"J. Alves, N. Cruz","doi":"10.1109/OCEANS.2014.7003229","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003229","url":null,"abstract":"Robotic sailing vehicles can provide the support for carrying out long ocean sampling missions, using solely renewable energy for propulsion and for powering the computing, communication and electromechanical systems. The basic automatic sailing tasks required to visit a sequence of waypoints has already been correctly addressed by various teams. However, an effective system for specifying long term autonomous missions is necessary to fill the gap between the developers of the robotic platforms and the scientific end users, mainly interested in the data they can get. This paper presents a simple, flexible and easy to use mission programming system implemented in the autonomous sailing boat FASt. A mission is programmed by defining events and assigning to them sequences of high level actions. The support of conditional statements allows the implementation of a basic control flow mechanism to make route decisions during the deployment of the mission. Examples are presented to illustrate the construction of mission programs.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"200 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116151259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A ferrite tubular linear permanent magnet generator (FTLPMG) analysis and design","authors":"G. Cipriani, V. Di Dio, V. Franzitta, A. Russo, M. Trapanese, A. Viola","doi":"10.1109/OCEANS.2014.7003179","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003179","url":null,"abstract":"Several linear synchronous generators for the exploitation of sea wave energy have been proposed. Such machines do not require reactive power for the magnetization since they use permanent magnets for the excitation. The use of permanent magnets in a rough environment such as the marine environment may be a very weak point in the application of these kind of devices. In order to overcome this difficulty, the authors in this paper propose a linear synchronous electrical generator. Its excitation uses ferrites as suitable solutions to extract energy from sea waves. This paper describes the analysis and design of an improved axially magnetized tubular permanent-magnet machine in which several innovative constructive solutions have been carried out to build a low cost, easy to assemble and robust machine. A Ferrite Tubular Linear Permanent Magnet Generator prototype has been made. Several simulation results are shown illustrating the system response to various outputs, including externally applied loads.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114689605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acoustic design and testing of the R/V INVESTIGATOR: A 94 meter research vessel","authors":"J. Spence, R. Fischer","doi":"10.1109/OCEANS.2014.7003205","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003205","url":null,"abstract":"The RV INVESTIGATOR is a quiet research vessel that has recently been built for CSIRO, the Australian Commonwealth Scientific and Industrial Research Organization. The vessel has stringent noise and vibration criteria, particularly with respect to underwater noise. Significant efforts were required in order for the vessel to be properly designed, constructed, and tested. This paper describes the efforts that were undertaken to achieve the noise goals and also presents the results of testing.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126320616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distributed smart sensor scheduling for underwater target tracking","authors":"J. Hare, Shalabh Gupta, Junnan Song","doi":"10.1109/OCEANS.2014.7003068","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003068","url":null,"abstract":"Underwater Sensor Networks include multiple sensor nodes that possess the ability to sense and communicate the environmental information where they are deployed. It is desired that these networks are intelligent in the sense that they allow for rapid deployment, self-organization, energy conservation, and fault tolerance via implementation of rapid multi-objective optimization algorithms. This paper proposes a decentralized sensor scheduling approach that enables dynamic space-time clustering for an energy-efficient target-tracking sensor network. Each sensor node is modeled as a Probabilistic Finite State Automata (PFSA) that governs its energy consumption, sensing, and communication activities. This PFSA allows the sensor nodes to dynamically change their states to conserve energy when a target is absent and turn on their high power sensing devices when the target is present. The algorithm proposed is compared with traditional scheduling schemes and the results show that the proposed method conserves energy while maintaining an accurate track estimation in a decentralized manor.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131922031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Near-sea multi-target opportunistic multiple-input multiple-output detection","authors":"M. Biagi, S. Rinauro, S. Colonnese, Stefano Pergoloni, R. Cusani, G. Scarano","doi":"10.1109/OCEANS.2014.7003202","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003202","url":null,"abstract":"The passive radar uses opportunistic illuminators, such as FM radio or TV transmitters, cellular telephone base stations, etc., to detect and track moving targets. Due to the fact that the radar itself does not transmit any power, it is undetectable. The other advantages of passive radar include its low power consumption, low cost and potential ability to detect stealth targets, due to the multistatic geometry and low frequencies used as weel as, it reduces electromagnetic pollution. This paper tackles with the problem of detecting targets close to the coastal and present on the sea surface by using opportunistic signals as The receiving operations aim at detecting the possible presence of reflective objects by stressing the diversity properties of the multiple-input multiple-output configuration due to multiple transmissions related to different communication services.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130111252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance analysis of hybrid ARQ schemes in underwater acoustic networks","authors":"J. Yu, Hui-fang Chen, Lei Xie, Jun-hong Cui","doi":"10.1109/OCEANS.2014.7003000","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003000","url":null,"abstract":"The characteristics of the underwater acoustic communication, such as large propagation delay, high bit error rate and half-duplex, bring great challenges to traditional automatic repeat request (ARQ) schemes. In this paper, we propose two hybrid ARQ (HARQ) schemes, Type-I HARQ and Type-II HARQ, for the underwater acoustic system according to the specific characteristics of the underwater acoustic communication. The performance of both HARQ schemes, in terms of the throughput efficiency, the average transmission delay of a packet and the packet error rate, is analyzed and derived. Simulation results show that the performance of the HARQ schemes is better than that of the pure ARQ schemes, the wait-stop ARQ and M-ARQ, especially for the small SNR. Moreover, simulation results also reveal that the Type-I HARQ scheme has an obvious advantage in the case of moderate SNR (7~10dB), while the Type-II HARQ scheme is still contributing when the SNR is as low as 5 dB.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131853925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"US integrated ocean observing system (IOOS®)-enabling decisions, advancing technologies","authors":"Z. Willis","doi":"10.1109/OCEANS.2014.7003064","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003064","url":null,"abstract":"The United States Integrated Ocean Observing System (IOOS®) is a user-driven, coordinated network of people, organizations, and technology that generate and disseminate continuous data about our coastal waters, Great Lakes, and oceans supported by strong research and development activities. IOOS® is our Eyes on our Oceans, Coasts and Great Lakes that enable the United States to track, predict, manage, and adapt to changes in our marine environment and deliver critical information to decision makers to improve safety, enhance our economy and protect our environment. IOOS enables decision making every day and fosters advances in science and technology. IOOS, in the United States, has been compared to the National Weather Service but an unanswered question is whether there exists an “ocean enterprise” like the weather enterprise. Technologies must be incubated and rapidly inserted to keep the US IOOS system operating effectively and efficiently. Since oceans know no boundaries, US IOOS is also the United States' contribution to the Global Ocean Observing System which is part of the ocean contribution to the Global Earth Observation Systems of Systems (GEOSS). US IOOS is supporting the Blue Planet Initiative under GEOSS in a number of efforts.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131890318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}