OCEANS 2008最新文献

{"title":"Prediction of impacts of discharged dissociated water in methane hydrate on environment","authors":"Y. Ishihara, I. Yabe, K. Asano","doi":"10.1109/OCEANS.2008.5152092","DOIUrl":"https://doi.org/10.1109/OCEANS.2008.5152092","url":null,"abstract":"In the development of a model to predict the impacts caused by the discharge of dissociated water, we collected and analyzed the parameters needed for the model in the area for the calculation. The parameters are based on the existing study and the surveyed results. The prototype of this model was established to assess the diffusion process of the water which released from the seabed or water column. As for the hazards of salinity and temperature changing due to methane hydrate dissociation in water, we review the existing study about the impacts on behaviors of marine organisms. In this study, the dissociated water discharged in surface layer, middle layer and bottom deep layer respectively. We calculated the extension range where the dissociated water influences the marine environment. The discharged dissociated water assumed the fresh water that was same temperature as the seawater at the bottom of the sea. The diffusing area of the dissociated water went up in the direction of the surface of the sea, because the densities of dissociated water are lower than seawater in the surrounding. It extends, and it has diffused horizontally by the flow of the each level. There is little influence on the marine organism in bottom of the sea, if the densities of the discharged dissociated water are lower than peripheral seawater.","PeriodicalId":113677,"journal":{"name":"OCEANS 2008","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122974155","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 power assignment mechanism for underwater wireless multimedia","authors":"Chin-Feng Lin, Shun-Hsyung Chang, Jiang-Yao Chen, Jung-Ting Yan","doi":"10.1109/OCEANS.2008.5151928","DOIUrl":"https://doi.org/10.1109/OCEANS.2008.5151928","url":null,"abstract":"In this paper, we propose an orthogonal variable spreading factor (OVSF) based underwater wireless multimedia (UWM) system. An essential feature of this system is power assignment mechanism, direct mapping (DM) strategy, OVSF technology, unequal error protection schemes, and adaptive modulation are granted to messages that can tolerate high bit error rate (BER). Simulation results show that the proposed scheme can not only fulfill the quality of services (QoS) required by a UWM system, but also achieve the mission of maximum transmission bit rates or minimum transmission power. For the purpose of verifying the proposed argument, a simulation has been done and the results match the derivation very well.","PeriodicalId":113677,"journal":{"name":"OCEANS 2008","volume":"213 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114160127","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":"Payload sensors, navigation and risk reduction for AUV under ice surveys","authors":"B. Jalving, J.E. Faugstadmo, K. Vestgård, O. Hegrenaes, O. Engelhardtsen, B. Hyland","doi":"10.1109/OCEANS.2008.5151987","DOIUrl":"https://doi.org/10.1109/OCEANS.2008.5151987","url":null,"abstract":"AUVs have proved robustness and high performance in applications including naval mine counter measures, marine research and deep water offshore oil and gas surveys. A next step is to introduce AUVs to under ice geophysical surveys. A main challenge for regular under ice operations is to handle the risk of a loss of a vehicle, or long operational interruptions. The paper discusses how to reduce this risk by careful tailoring of critical AUV subsystems. A fundamental requirement is to apply a robust, well designed and well proven vehicle, continually upgraded from field experiences. Another main challenge is to design a sensor suite that allows for cost efficient and fast mapping of the vast areas under ice. A geophysical sensor suite is presented and solutions for high area coverage rates examined.","PeriodicalId":113677,"journal":{"name":"OCEANS 2008","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114180627","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 positioning of AUV with data transmission using SS acoustic signal","authors":"Y. Watanabe, H. Ochi, T. Shimura, T. Hattori","doi":"10.1109/OCEANS.2008.5151800","DOIUrl":"https://doi.org/10.1109/OCEANS.2008.5151800","url":null,"abstract":"In recent years, precious observations by autonomous underwater vehicle (AUV) have been performed. Tracking and navigation of AUV are important for precious observations. In Japan agency for Marine-earth Science and Technology (JAMSTEC) the observations with AUV ldquoURASHIMArdquo have been implemented in deep ocean area. AUV URASHIMA is navigated by an inertial navigation system (INS) mainly. The absolute position of AUV is tracked on the support vessel with super short base-line (SSBL) method of acoustic positioning. And sometime the own position in AUV is updated by the SSBL estimation result to correct the drift error of INS. However the SSBL is not so accurate. So the position correction includes the SSBL error and the position correction is performed drastically. In this paper, a method for accurate tracking of AUV and rapid correction of the INS status is proposed. The tracking is mainly achieved by SSBL on the support vessel. Additionally the INS data is transmitted from AUV including the acoustic positioning signal. The INS output of relative position to past own position is very accurate within short time. The INS data is used for tracking. Furthermore the position result estimated on the vessel is transmitted to AUV with next interrogation signal. And the own position in AUV is rapidly updated with accurate estimation. Some digital data including INS data is modulated with phase shift keying (PSK) method and direct sequence spread spectrum (DSSS) technique for transmission with acoustic positioning signal. The proposed method was considered by simulation. And good results were obtained.","PeriodicalId":113677,"journal":{"name":"OCEANS 2008","volume":"319 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116229735","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":"Target detection in M-disparate sonar platforms using multichannel hypothesis testing","authors":"J. D. Tucker, N. Klausner, M. Azimi-Sadjadi","doi":"10.1109/OCEANS.2008.5151818","DOIUrl":"https://doi.org/10.1109/OCEANS.2008.5151818","url":null,"abstract":"The use of multiple disparate sonars allows one to exploit a high resolution sonar with good target definition while taking advantage of the clutter suppressing abilities of a low resolution broadband sonar co-registered over the same region to provide potentially much better detection and classification performance comparing to those of the single sonar cases. In this paper the standard Neyman-Pearson detector is extended to the dual disparate sonar case allowing target detection across two sensory platforms simultaneously. For three disparate sonar platforms, two detectors are implemented with the final decisions being fused. Test results of the proposed methods on a data set of underwater side-scan sonar imagery are presented. This database contains data from 3 different side-scan sonars, namely one high frequency sonar and two broadband sonars, operating at three different frequencies and bandwidths. The data was collected in different bottom conditions and contains various mine-like and non-mine-like objects with varying degree of difficultly and bottom clutter. Test results illustrate the effectiveness of the proposed detection system in terms of probability of detection, false alarm rate, and the receiver operating characteristic (ROC) curve.","PeriodicalId":113677,"journal":{"name":"OCEANS 2008","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116661840","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":"Behavior of the deep submersible hatch in deep sea","authors":"I. Kawama, T. Yoshiume, T. Murashima, Y. Imai, T. Sakurai, K. Ito, N. Wakita, A. Uchihara","doi":"10.1109/OCEANS.2008.5152085","DOIUrl":"https://doi.org/10.1109/OCEANS.2008.5152085","url":null,"abstract":"Deep manned submersible ldquoSHINKAI 6500rdquo was built in 1989, and has been operated by Japan Agency for Marine-Earth Science and Technology (JAMSTEC). She has capability to dive down to 6500 m depth. Currently, she made 1097 dives until the end of July 2008. A round hatch on the top of the pressure hull is designed to constitute a part of the spherical pressure hull, and is very important structure to keep atmospheric pressure and waterproof in the hull. Therefore, we handle a hatch carefully in every operation, and moreover, we remove a hatch from the pressure hull at the time of the annual-maintenance and are doing the careful overhaul which involves the measurement and exchange of components. The number of her diving exceeded 1000 times, and she will reach 20 years old shortly. As consideration for that, an operation team, an engineering division and a ship builder implemented investigation for reconfirmation about soundness and safety of the pressure hull including a hatch. In this report, the result of investigation and evaluation about behavior of a hatch including the pressure hull is described.","PeriodicalId":113677,"journal":{"name":"OCEANS 2008","volume":"2016 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125644554","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":"Relationships between metallothionein induction, cadmium, copper and zinc levels and environmental parameters in the soft shell clam Mya arenaria in the Saguenay fjord and the St. Lawrence River maritime estuary","authors":"J. Pellerin, J. Amiard","doi":"10.1109/OCEANS.2008.5152082","DOIUrl":"https://doi.org/10.1109/OCEANS.2008.5152082","url":null,"abstract":"Physiological status of Mya arenaria is threatened in the Saguenay-Saint Lawrence system due to inputs of many kinds of pollutants from anthropogenic and industrial origins. Investigations of the health of M. arenaria were carried out using metallothioneins concentrations as biomarkers of metallic contamination in relation with concentrations of metals.","PeriodicalId":113677,"journal":{"name":"OCEANS 2008","volume":"27 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114010891","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":"NOAA's integrated observations and data management and strategic portfolio tools","authors":"M. Yapur, L. E. Miller","doi":"10.1109/OCEANS.2008.5151991","DOIUrl":"https://doi.org/10.1109/OCEANS.2008.5151991","url":null,"abstract":"The National Oceanic and Atmospheric Administration is developing tools to support the analysis and acquisition of architectures for integrated observations and data management strategic portfolios. One of these tools is the ldquoCasaNOSA analysis toolrdquo (CASRT), a desktop software tool that retrieves and matches observing requirements and capabilities, and uses a variety of algorithms to measure the degree of fit or performance between systems and requirements at the attribute level. This tool pulls data from the database of NOAA observing and data management requirements and capabilities that NESDIS' Office of Systems Development has compiled over the last five years. NOAA's operational and science-oriented programs have more than 800 mission-critical observing requirements. NOAA operates over 80 different land, sea, and space-based observing systems, and also obtains data from a wide range of public and private sector sources. NOAA's observing requirements and capabilities are defined in terms of key attributes such as geographic coverage, horizontal or vertical resolution, measurement accuracy, and re-visit frequency. The NOAA database of requirements and capabilities resides in an open source, Web-based repository system and is managed through a suite of collaborative tools. Results from these CASRT gap analyses will be used for investment portfolio analysis, decision support, statistical analysis, and enterprise architecture modeling.","PeriodicalId":113677,"journal":{"name":"OCEANS 2008","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122730250","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":"Submerged water current turbines","authors":"M.N.I. Khan, M. Iqbal, M. Hinchey","doi":"10.1109/OCEANS.2008.5151891","DOIUrl":"https://doi.org/10.1109/OCEANS.2008.5151891","url":null,"abstract":"Technologies to harness ocean current energy are at an early developing stage, and only a few prototypes and demonstration units have yet been tested. Ocean currents are potentially significant and currently untapped resource of energy. Ocean currents thus contain an abundant source of energy that can be captured and converted to a usable form. This paper discusses the performance of three different types of Savonius rotors used as water current turbines. Rotors design and test results in a tow tank are presented. All three rotors have same cross sectional area. Test results shows that double stage rotor has lower cut-in speed and produces higher torque when compared to single and three stage rotor design. These rotors were tested to determine a suitable water current turbine for a micro seafloor power generation system.","PeriodicalId":113677,"journal":{"name":"OCEANS 2008","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122913283","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":"Retrospective and prospective views of the Ocean Observing System in the Gulf of Maine","authors":"N. Pettigrew, J. Wallinga, L. Mangum, F. Neville","doi":"10.1109/OCEANS.2008.5152030","DOIUrl":"https://doi.org/10.1109/OCEANS.2008.5152030","url":null,"abstract":"The Gulf of Maine Ocean Observing System (GoMOOS) is a comprehensive prototype integrated coastal ocean observing system that was established in the summer of 2001. Its current configuration includes eleven solar-powered buoy-monitored locations with physical and optical sensors, four shore-based long-range HF radar systems for surface current measurement, operational circulation and wave models, satellite observations, inshore nutrient monitoring, and hourly web-delivery of data. It serves a broad array of real-time oceanographic and marine meteorological data and data products to scientists, state and federal regulators, the National Weather Service, both the US and Canadian Coast Guards, the National Data Buoy Center, educators, regional natural- resource managers, the Gulf of Maine fishing and maritime industries, local airports and airlines, sailors, and the general public. The ocean observing system that can be thought of as consisting of four major subsystems: the data acquisition subsystem; the data handling, processing, and archiving subsystem; the system of numerical nowcast and forecast models; and a web-based data distribution/presentation subsystem. The Gulf of Maine is a harsh operational environment. Winter storms pose severe challenges including the build up of sea ice on buoy, its solar panels, and its meteorological sensors. In summer the productive waters of the gulf can present severe biofouling problems that affect the operation of optical sensors. Thus, the periods of most difficult field operations coincide with the periods of greatest data value in terms of marine safety, search and rescue, and the monitoring biological productivity. Never-the-less, the data returns for the GoMOOS ocean sensor array has averaged approximately 90% over the first seven years of operation. This unusually high rate of data return is due in large part to our operational six-month duty/maintenance cycle on all equipment. We have 22 buoys for 11 locations, and 22 complete sets of instrumentation that are rotated in and out of service on a six month schedule. The challenges of the Gulf of Maine physical environment were largely understood a priori, and were incorporated into the system design criteria and the blueprints for the service and maintenance protocols. However, there were unanticipated challenges in the funding process that have caused the greatest difficulties, and which continue to pose a serious threat to continued operation and success of this ocean observing system, as well as others observing systems in the United States. Funding for the system has been chronically short and subject to the unpredictable fluctuations of a US congressional appropriations process. The inadequacy and variability of funding has substantially hampered the operations of many of the Integrated Ocean Observing Systems (IOOS), including GoMOOS, and has hindered technological improvements. The funding crisis has deepened to the point that, unless this trend i","PeriodicalId":113677,"journal":{"name":"OCEANS 2008","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132847121","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}