2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies最新文献

{"title":"Outline of New Cabled Observation System off Toyohashi","authors":"K. Asakawa, T. Yokobiki, T. Goto, E. Araki, M. Kinoshita, K. Mitsuzawa","doi":"10.1109/UT.2007.370955","DOIUrl":"https://doi.org/10.1109/UT.2007.370955","url":null,"abstract":"A new cabled observation system off the coast of Toyohashi in central Japan is now being developed. The system uses a couple of former underwater optical telecommunication cables of about 60 kilo-meters long. The authors will use the cable in two ways simultaneously. One is to build a new observatory at the end of the cable. Underwater sensors including a broadband seismometer, a precise water-pressure sensor and an electro-magnetometer will be connected to the junction unit using underwater mateable connectors. The other is to use the same cable simultaneously as a long emitting antenna to monitor the electro-magnetic property of the earth crust. We have developed a new time synchronization system. It provides precise 1PPS signal, clock and NMEA data to underwater sensors. In this paper, we will describe the outline of the system. The longterm monitoring will start in this April.","PeriodicalId":345403,"journal":{"name":"2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131730587","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":"AquaBox Series: Small Underwater Robot Systems for Shallow Water Observation","authors":"S. Ohata, Yu Eriguchi, K. Ishii","doi":"10.1109/UT.2007.370796","DOIUrl":"https://doi.org/10.1109/UT.2007.370796","url":null,"abstract":"Various kinds of robots have been developed parallel with the progress of computers and information processing technology, and the operations in the extreme environments, such as disaster areas, space and ocean, are getting one of the practical solutions for those hazardous missions. The underwater robots are one of the extreme environment robots and expected as one of solutions for underwater activities, i.e. maintenance of underwater structures, observations, scientific research, where research area is getting wide and deep and also underwater structures are getting large-scale and deep depth. Their efficiencies have been investigated during recent decades and are proven by ocean experiments. However, the robotic system including the support vessels is still big scale, and not so easy to handle by a few researchers. In this paper, we describe the underwater robot \"AquaBox\" series developed aiming at handy, small underwater robots which can be operated by a few researchers.","PeriodicalId":345403,"journal":{"name":"2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124000769","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":"Multidisciplinary observations at an expandable sub-marine cabled station off the Hatsushima island, the Sagami bay, Japan","authors":"T. Kasaya, K. Mitsuzawa, T. Goto, K. Sayanagi, E. Araki, K. Asakawa, R. Iwase, H. Mikada, T. Nagao","doi":"10.1109/UT.2007.370819","DOIUrl":"https://doi.org/10.1109/UT.2007.370819","url":null,"abstract":"Western part of Sagami Bay is one of the active tectonic areas in Japan. In this area, Teishi Knoll, volcanic scamount, erupted in 1989 and the earthquake swarms occurs repeatedly every few years in the eastern coast of the Izu Peninsula. The real-time deep sea floor observatory was deployed about 7 km off Hatsushima Island, Sagami Bay, at a depth of 1174 m in 1993 to monitor seismic activities, underwater pressure, water temperature and deep currents. The video camera and lights were also mounted in the observatory to monitor the relations among biological activities associated with the tectonic activities. The observation system including submarine electro-optical cable with a length of 8 km was completely renewed in 2000. The several underwater-mateable connectors are installed in the new observatory for additional observation instruments. An ocean bottom electro-magnetic meter(OBEM), precise pressure sensor and ocean bottom gravity meter were installed using ROV Hyper-Dolphin in the cruise of R/V Natsushima from January 9 to 14, 2005. We started to operate them at February 10, 2005 after checking those of data qualities. Observed data have been sent to Yokohama institute, JAMSTEC. Around the Sagami bay, seismic activity is very high. A large earthquake (M5.4) occurred off Izu peninsula at April 21, 2006, and submarine land slide was then generated. Generated mud flow reached to the Hatsushima station, and moved positions of some sensors. The video camera was able to take a movie of mud flow. An OBEM and other sensors also detected some distinctive changes with the mud flow.","PeriodicalId":345403,"journal":{"name":"2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117026991","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":"JMA's new Ocean Bottom Seismographs (OBS) using marine cable installed at the Sea of Enshu to the Sea of Kumano","authors":"S. Saito, K. Moriwaki, Y. Yamada","doi":"10.1109/UT.2007.370828","DOIUrl":"https://doi.org/10.1109/UT.2007.370828","url":null,"abstract":"JMA started a project in 2004 to install new ocean bottom seismographs (OBS) using marine cable at around assumed focal regions of anticipated Tokai and Tonankai earthquakes. JMA installed ocean bottom seismographs (OBS) in 1978 at assumed focal region of Tokai earthquake at the sea of Enshu, and has been keeping seismic observation using them; the started project is to install new OBS on west of the existing OBS. The aim of new OBS is improvement of detection ability of small earthquakes, and also prompt detection of large earthquake and precise determination of its magnitude for early earthquake warning.","PeriodicalId":345403,"journal":{"name":"2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127643780","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":"NEMO-SNI real-time cabled seafloor observatory (southern Italy): operation assessment after two years from the deployment and next perspectives","authors":"P. Favali, L. Beranzoli, F. Italiano, N. collaboration","doi":"10.1109/UT.2007.370766","DOIUrl":"https://doi.org/10.1109/UT.2007.370766","url":null,"abstract":"The NEMO-SN1 multiparameter real-time cabled seafloor observatory is operating in the central Mediterranean basin, offshore Eastern Sicily island (Italy) at 2100 m w.d., since 2005 thanks to an agreement between Istituto Nazionale di Fisica Nucleare (INFN) and Istituto Nazionale di Geofisica e Vulcanologia (INGV). During the first two years of life of NEMO-SN1, some maintenance operations were needed to restore the cable functionalities and also to change the cable path near shore, in order to improve its safety from heavy sea. Meanwhile, a project submitted jointly by INGV and INFN was approved by the local governmental authorities of Sicily in order to enhance the observatory. The project, named PEGASO, is aimed at developing infrastructures for the management of deep seafloor scientific experiments in the NEMO-SN1 site. An overview of the activity on the observatory during its first two years of life will be given and the PEGASO project developments will be presented as well.","PeriodicalId":345403,"journal":{"name":"2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117223250","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":"Measurement of swimming speed in sperm whales","authors":"K. Aoki, M. Amano, N. Sugiyama, H. Muramoto, M. Suzuki, M. Yoshioka, K. Mori, D. Tokuda, N. Miyazaki","doi":"10.1109/UT.2007.370754","DOIUrl":"https://doi.org/10.1109/UT.2007.370754","url":null,"abstract":"Cetaceans spend their entire life in the water. Hence these animals represent important models for studying adaptations for aquatic environment. Although many scientists have been interested in how fast they can swim, accurate swimming speed measurements of free-ranging cetaceans are rare because it is difficult to observe them continuously. In particular, little is known about routine swimming speed of deep diver, such as sperm whales. To measure swimming speed of the sperm whales, we attached two-type suction-cup-attached tags including a data logger to sperm whales. One type was similar to that employed in several other studies (Type A). The other type was modified by us to get more precious velocity data (Type B). We attached the two-type tag to a total of 11 sperm whales (8 Type A and 3 Type B) and, obtained accurate swimming speed with 8 whales of them (5 Type A and 3 Type B). A total of 136 hours of accurate swimming speed data including 137 dives was obtained. Average velocity during the dive was 1.77 plusmn 0.39 m s-1 (n =137). Maximum velocity of each whale was 4.2-9.6 m s-1 (n = 8). In addition, we found the oscillations caused by the tail beat in the time-series velocity data, which was obtained by modified suction-cup-attached tags (Type B). The modified tags provide us routine and maximum swimming speed of the whales as well as the information of the tail beat.","PeriodicalId":345403,"journal":{"name":"2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121760147","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":"Long-term seafloor and land-based sesismological monitoring at southwestern end of the Kurile subduction zone, based on more than six-year continuous observation","authors":"T. Watanabe, H. Mikada, M. Kasahara","doi":"10.1109/UT.2007.370817","DOIUrl":"https://doi.org/10.1109/UT.2007.370817","url":null,"abstract":"Around Japanese islands, most of subduction-related megathrust earthquakes occur offshore seismogenic zone, and are difficult targets in seismological and disaster mitigation studies. In June 1999, JAMSTEC installed a seismological/geophysical cabled observatory with length of approximately 240 km, off Kushiro-Tokachi, southeastern off Hokkaido, Japan. The system locates near southwestern end of the Kurile subduction zone, where megathrust earthquakes are taking place repeatedly. For in-situ seismological/geophysical monitoring at plate boundary, which is one of the leading hopes to investigate the subduction process and related phenomena in detail, we reviewed more than six-year automatic event-based seismological data since September 2000, when a continuous recording and related automatic event detection against cabled seismological data combined with land-based observation started. Above long-term observation includes onset of a megathrust earthquake (2003 Tokachi-oki earthquake, M8.0) just beneath our cabled system and the following intense aftershock activity, which we first experienced on the ocean floor. In this paper, we summarize several remarks based on the results, including experiences with our observation.","PeriodicalId":345403,"journal":{"name":"2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116213053","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":"Observation of Seafloor Crustal Deformation at the Nankai Margin, Japan","authors":"K. Tadokoro, M. Ando, T. Okuda, S. Sugimoto, T. Watanabe, Y. Aizawa, J. Yasuda, M. Kuno","doi":"10.1109/UT.2007.370790","DOIUrl":"https://doi.org/10.1109/UT.2007.370790","url":null,"abstract":"We developed an observation system for measuring seafloor crustal deformation composed of precise acoustic ranging and kinematic positioning technique. The repeatability of the system is 3 cm in both horizontal components. We observed the coseismic crustal deformation caused by the two Ml class offshore earthquakes at the Kumano Bay, Japan. From the repeated observation at the Suruga Bay, we obtained the horizontal velocity field that is consistent to the vectors observed by the nationwide GPS observation network. The observation of seafloor crustal deformation can provide better information of seafloor crustal deformation associated with crustal activities, such as coseismic displacement and plate convergence.","PeriodicalId":345403,"journal":{"name":"2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126544268","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":"Measurement of Seabed Roughness with Laser Scanning System","authors":"Chau-Chang Wang, Po-Chi Chen, Minhui Hung, C. Chu, D. Tang, T. Hefner","doi":"10.1109/UT.2007.370838","DOIUrl":"https://doi.org/10.1109/UT.2007.370838","url":null,"abstract":"Knowing the temporal change of the seabed, we can understand the nature of the undersea environment in more details. The scale of the features on the seabed varies from meters for large sandwaves, and down to less than one millimeter for the prints left by marine creatures. So far, there is not a single instrument that can cover the whole range and still preserve the resolution. For measuring small-scale roughness of seabed, laser scanning is an alternative. In this work, we report the integration of Seabed Laser Scanner (SLS), developed by Institute of Undersea Technology, Sun Yat-sen University, on the linear stage of In Situ Measurement of Porosity 2 (IMP2), developed by Applied Physics Laboratory, University of Washington to carry out deep sea sediment 2D roughness measurement and comparison. IMP2 consists of a 4 meter long scaffold and a linear stage. SLS is mounted on the linear stage to carry out the scanning. To simplify the integration and avoid the possible failure coming from the additional underwater connections, SLS is designed to be a self-contained system. It runs on a PC104 with Windows XP and feeds on its own battery pack. The only interaction between the two systems is achieved by the proximity of a set of magnets and a relay. As the linear stage starts, the first magnet triggers SLS to power up and standby. As the stage comes to the end of the rack, the second magnet triggers the image acquisition. The integrated system was deployed three times during the Shallow Acoustics Experiment 2006, about eighty miles off the coast of New Jersey. We successfully retrieved data from SLS for the first two trials; the third trial failed due to the aborted mission of IMP2. A 300 cm times 30 cm and a 350 cm times 25 cm seafloor were mapped at 80-meter water depth. From the reconstructed 3D surfaces, we found that the seafloor is full of shell debris and covered by mud-like sediment. The 2D spectra were estimated from the 3D surface. The results indicated that the seafloor roughness follows a power-law spectrum and isotropic. These spectra estimated provide the boundary condition for modeling the acoustic propagation and scattering.","PeriodicalId":345403,"journal":{"name":"2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131465659","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":"Bathymetric survey at hydrothermal site by L-array Interferometric sonar mounted on AUV-r2D4","authors":"H. Koyama, A. Asada, T. Ura, Han Jun, T. Obara, K. Nagahasi","doi":"10.1109/UT.2007.370845","DOIUrl":"https://doi.org/10.1109/UT.2007.370845","url":null,"abstract":"Autonomous underwater vehicle is expected for its stability as platform of many sensors. AUV-r2D4 that can act under the sea up to a depth of 4,000 m was built for the purpose of finding and surveying hydrothermal deposit and already with many advanced sensors some investigations have been performed. For r2D4 we have been developing new bathymetric sonar that arranges three hydrophones in L-array shape beside both side's transmitters usually used as side scan sonar. These systems calculating the angles of arrival of backscatter signals from differential phase called interferometric or bathymetric side scan consist of two hydrophones and one transmitter. Our new system arranged three hydrophones at L-array shape (LA-IFS) enabled us to resolve unwrapping problem and led us to make higher resolution bathymetric chart. LA-IFS has advantages for AUV because of its simple design and energy saving performance. And as bathymeter its long range and dense swath bathymetry, of course backscattering, provides effective alternative to AUV equipment. We have performed some investigation with r2D4. In this paper we introduce the results of LA-IFS's bathymetric surveying at the Central Indian Ridge on December 2006.","PeriodicalId":345403,"journal":{"name":"2007 Symposium on Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134414748","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}