Pub Date : 2014-04-07DOI: 10.1109/OCEANS-TAIPEI.2014.6964410
E. Araki, T. Kimura, S. Kodaira, S. Miura, M. Takaesu, N. Takahashi, M. Nakano, Y. Kaneda
An experiment was performed to shoot airgun and receive the seismic signal with long-term seafloor seismic observatories (DONET seafloor and IODP borehole observatory) above the seismogenic zone in the Nankai Trough. The purpose of the experiment is to assess possibility to detect temporal change in seismic velocity structure which might change due to the stress accumulation in and around the subducting seismogenic plate interface, by repeated airgun survey, as well as to evaluate present stress state in the area through seismic anisotropy. The initial analysis of the experiment suggests that airgun shooting in accurate position especially in terms of the distance from the receiving observatory is necessary to treat the repeated shot record as the shooting in the same condition. P-wave first motion data from a circle shooting around the borehole observatory showed clear azimuthal dependency when correction was made for seafloor topography variation, which was consistent with known other indicators for seismic anisotropy and stress state.
{"title":"Experiment to detect temporal change of seismic velocity in the subducting plate boundary in the Nankai Trough using the DONET submarine cabled observation network and airgun controlled source","authors":"E. Araki, T. Kimura, S. Kodaira, S. Miura, M. Takaesu, N. Takahashi, M. Nakano, Y. Kaneda","doi":"10.1109/OCEANS-TAIPEI.2014.6964410","DOIUrl":"https://doi.org/10.1109/OCEANS-TAIPEI.2014.6964410","url":null,"abstract":"An experiment was performed to shoot airgun and receive the seismic signal with long-term seafloor seismic observatories (DONET seafloor and IODP borehole observatory) above the seismogenic zone in the Nankai Trough. The purpose of the experiment is to assess possibility to detect temporal change in seismic velocity structure which might change due to the stress accumulation in and around the subducting seismogenic plate interface, by repeated airgun survey, as well as to evaluate present stress state in the area through seismic anisotropy. The initial analysis of the experiment suggests that airgun shooting in accurate position especially in terms of the distance from the receiving observatory is necessary to treat the repeated shot record as the shooting in the same condition. P-wave first motion data from a circle shooting around the borehole observatory showed clear azimuthal dependency when correction was made for seafloor topography variation, which was consistent with known other indicators for seismic anisotropy and stress state.","PeriodicalId":114739,"journal":{"name":"OCEANS 2014 - TAIPEI","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127563951","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}
Pub Date : 2014-04-07DOI: 10.1109/OCEANS-TAIPEI.2014.6964569
J. Hermand, Longxiang Guo, J. Randall, P. Brehmer
A submersible digital holographic microscope (DHM) Holoflow@Sea was deployed during AWA fisheries surveys conducted in March 2013 and 2014 in the large upwelling ecosystem of the Canaries Current. The microscope collected about half a million of holograms of microorganisms and other particles suspended in the water column. Selected new results of reconstruction of phyto- and zooplankton species using improved algorithms with respect to previously published results are presented. Amplitude images are more detailed and, for some species, phase images provide useful additional information about morphology and composition. Extensive analysis confirms that the submersible DHM is suitable for in-situ imaging of organisms in the size range 2 μm-200 μm and species identification. When compared to standard procedures the microscope allows to rapidly monitor planktonic communities over a wide area. It contributes to a better understanding of the organization and functioning of the ecosystem and in particular the link between biogeochemistry cycles and small pelagic fish stock dynamics.
{"title":"Non-destructive optical holographic imaging of microorganisms in situ off the Senegalese coast","authors":"J. Hermand, Longxiang Guo, J. Randall, P. Brehmer","doi":"10.1109/OCEANS-TAIPEI.2014.6964569","DOIUrl":"https://doi.org/10.1109/OCEANS-TAIPEI.2014.6964569","url":null,"abstract":"A submersible digital holographic microscope (DHM) Holoflow@Sea was deployed during AWA fisheries surveys conducted in March 2013 and 2014 in the large upwelling ecosystem of the Canaries Current. The microscope collected about half a million of holograms of microorganisms and other particles suspended in the water column. Selected new results of reconstruction of phyto- and zooplankton species using improved algorithms with respect to previously published results are presented. Amplitude images are more detailed and, for some species, phase images provide useful additional information about morphology and composition. Extensive analysis confirms that the submersible DHM is suitable for in-situ imaging of organisms in the size range 2 μm-200 μm and species identification. When compared to standard procedures the microscope allows to rapidly monitor planktonic communities over a wide area. It contributes to a better understanding of the organization and functioning of the ecosystem and in particular the link between biogeochemistry cycles and small pelagic fish stock dynamics.","PeriodicalId":114739,"journal":{"name":"OCEANS 2014 - TAIPEI","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127650930","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}
Pub Date : 2014-04-07DOI: 10.1109/OCEANS-TAIPEI.2014.6964493
Khalid El-Darymli, C. Moloney, E. Gill, Peter F. McGuire, D. Power, J. Deepakumara
When signals exhibit non-Gaussian statistics, nonlinear signal processing techniques offer advantages over their linear counterparts. Nonlinearity in high-resolution synthetic aperture radar (SAR) imagery is an intrinsic phenomenon often overlooked in the radar literature. In this paper, we study the nonlinear dynamics, and the effect of detection, in SAR imagery. To this end, two complementary methods for exposing the nonlinear statistics are presented. The first method utilizes histogram fitting with relevant statistical models. The second method is based on hypothesis testing. Our results are demonstrated on real-world Radarsat-2 target chips. It is found that in the presence of extended targets (e.g., ships), the nonlinear effect in the SAR chip is predominant. Nonlinearity is observed to be negligible in the absence of extended targets. As the SAR chip is detected, the nonlinear dynamics are either diminished/altered (i.e., for power-detection) or obliterated (i.e., for magnitude-detection). To take full advantage of nonlinear statistics, it is recommended to utilize the complex-valued SAR image rather than the detected one. Furthermore, the Student's T location-scale distribution is seen to offer an excellent model for the SAR chip.
{"title":"Nonlinearity and the effect of detection on single-channel synthetic aperture radar imagery","authors":"Khalid El-Darymli, C. Moloney, E. Gill, Peter F. McGuire, D. Power, J. Deepakumara","doi":"10.1109/OCEANS-TAIPEI.2014.6964493","DOIUrl":"https://doi.org/10.1109/OCEANS-TAIPEI.2014.6964493","url":null,"abstract":"When signals exhibit non-Gaussian statistics, nonlinear signal processing techniques offer advantages over their linear counterparts. Nonlinearity in high-resolution synthetic aperture radar (SAR) imagery is an intrinsic phenomenon often overlooked in the radar literature. In this paper, we study the nonlinear dynamics, and the effect of detection, in SAR imagery. To this end, two complementary methods for exposing the nonlinear statistics are presented. The first method utilizes histogram fitting with relevant statistical models. The second method is based on hypothesis testing. Our results are demonstrated on real-world Radarsat-2 target chips. It is found that in the presence of extended targets (e.g., ships), the nonlinear effect in the SAR chip is predominant. Nonlinearity is observed to be negligible in the absence of extended targets. As the SAR chip is detected, the nonlinear dynamics are either diminished/altered (i.e., for power-detection) or obliterated (i.e., for magnitude-detection). To take full advantage of nonlinear statistics, it is recommended to utilize the complex-valued SAR image rather than the detected one. Furthermore, the Student's T location-scale distribution is seen to offer an excellent model for the SAR chip.","PeriodicalId":114739,"journal":{"name":"OCEANS 2014 - TAIPEI","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116775300","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}
Pub Date : 2014-04-07DOI: 10.1109/OCEANS-TAIPEI.2014.6964509
Jean-Marc Sinquin, Gael Quemener, J. Sorribas
Within the EUROFLEETS project, and linked to the EMODNet and Geo-Seas European projects, GLOBE (Global Oceanographic Bathymetry Explorer) is an innovative and generic software combining all necessary functionalities for cruise preparation, for collection, linking, processing and display of scientific data acquired during sea cruises, and for exporting data and information to the main marine data centers and networks.
{"title":"GLOBE software: An innovative software for Geoscience data processing and 3D/4D viewing","authors":"Jean-Marc Sinquin, Gael Quemener, J. Sorribas","doi":"10.1109/OCEANS-TAIPEI.2014.6964509","DOIUrl":"https://doi.org/10.1109/OCEANS-TAIPEI.2014.6964509","url":null,"abstract":"Within the EUROFLEETS project, and linked to the EMODNet and Geo-Seas European projects, GLOBE (Global Oceanographic Bathymetry Explorer) is an innovative and generic software combining all necessary functionalities for cruise preparation, for collection, linking, processing and display of scientific data acquired during sea cruises, and for exporting data and information to the main marine data centers and networks.","PeriodicalId":114739,"journal":{"name":"OCEANS 2014 - TAIPEI","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116812525","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}
Pub Date : 2014-04-07DOI: 10.1109/OCEANS-TAIPEI.2014.6964547
Shih-Jen Huang, Jung-Te Lin, Y. Lo, N. Kuo, Chung‐Ru Ho
In order to estimate the thermal plumes discharged from Chinshan and Kuosheng nuclear power plants on the coast of north Taiwan, this study uses the thermal infrared data from Landsat 7 ETM+(Enhanced Thematic Mapper Surface Temperature) to contrast with the in-situ SST measurement for the intake/discharge ports of the nuclear power plants. The near-infrared (band 4) data of Landsat 7 ETM+ are firstly applied to distinguish ocean and land, and then the thermal infrared (band 6) data are used to estimate SST. The algorithm of SST on north Taiwan is established in this study by the contrast between the in-situ SST data of the two nuclear power plants and the thermal infrared data of Landsat 7 ETM+. The standard deviation of SST retrieved through this algorithm is estimated to be 3.1°C, but the mean difference is near 0. According to the retrieved SST from the satellite data, the warm-plume (>4°C than offshore SST) discharge of Chinshan nuclear power plant reaches 540-1080 m far from its discharge port, but for Kuosheng Nuclear Power Plant, the farthest of the warm-plume discharge from the discharge port is 390-900 m. The retrieved SST gradually gets cooler by diffusion from the discharge port to the offshore. Apparently, the Landsat 7 ETM+ can be applied to measure the special variance of SST. The result also shows the area of significant thermal plume (>4°C than offshore SST) are about 0.01-1.3 km2 and 0.09-8.53 km2 for the Chinshan and Kuosheng nuclear plants respectively. Moreover, the significant thermal plume area is affected by tides. During the flood tide, the warm-plume discharge gets close to the coast, and it will make the significant thermal plume area increase. Besides, the second significant thermal plume (>2°C than offshore SST) is also increased during the ebb tide because the thermal plume may be taken away and diluted from the discharged port. However, due to different topographies, the area of thermal plume of the Kuosheng is broader than that of Chinshan nuclear power plant.
{"title":"The coastal sea surface temperature changes near the nuclear power plants of northern Taiwan observed from satellite images","authors":"Shih-Jen Huang, Jung-Te Lin, Y. Lo, N. Kuo, Chung‐Ru Ho","doi":"10.1109/OCEANS-TAIPEI.2014.6964547","DOIUrl":"https://doi.org/10.1109/OCEANS-TAIPEI.2014.6964547","url":null,"abstract":"In order to estimate the thermal plumes discharged from Chinshan and Kuosheng nuclear power plants on the coast of north Taiwan, this study uses the thermal infrared data from Landsat 7 ETM+(Enhanced Thematic Mapper Surface Temperature) to contrast with the in-situ SST measurement for the intake/discharge ports of the nuclear power plants. The near-infrared (band 4) data of Landsat 7 ETM+ are firstly applied to distinguish ocean and land, and then the thermal infrared (band 6) data are used to estimate SST. The algorithm of SST on north Taiwan is established in this study by the contrast between the in-situ SST data of the two nuclear power plants and the thermal infrared data of Landsat 7 ETM+. The standard deviation of SST retrieved through this algorithm is estimated to be 3.1°C, but the mean difference is near 0. According to the retrieved SST from the satellite data, the warm-plume (>4°C than offshore SST) discharge of Chinshan nuclear power plant reaches 540-1080 m far from its discharge port, but for Kuosheng Nuclear Power Plant, the farthest of the warm-plume discharge from the discharge port is 390-900 m. The retrieved SST gradually gets cooler by diffusion from the discharge port to the offshore. Apparently, the Landsat 7 ETM+ can be applied to measure the special variance of SST. The result also shows the area of significant thermal plume (>4°C than offshore SST) are about 0.01-1.3 km2 and 0.09-8.53 km2 for the Chinshan and Kuosheng nuclear plants respectively. Moreover, the significant thermal plume area is affected by tides. During the flood tide, the warm-plume discharge gets close to the coast, and it will make the significant thermal plume area increase. Besides, the second significant thermal plume (>2°C than offshore SST) is also increased during the ebb tide because the thermal plume may be taken away and diluted from the discharged port. However, due to different topographies, the area of thermal plume of the Kuosheng is broader than that of Chinshan nuclear power plant.","PeriodicalId":114739,"journal":{"name":"OCEANS 2014 - TAIPEI","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131258588","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}
Pub Date : 2014-04-07DOI: 10.1109/OCEANS-TAIPEI.2014.6964514
K. Kawaguchi, E. Araki, Masanori Hoshino, T. Yokobiki, H. Matsumoto, S. Nishida, Jin-Kyu Choi, T. Kimura, N. Takahashi, T. Baba, M. Nakano, Takeshi Nakamura, Y. Kaneda
DONET (Dense Ocean-floor Observatory Network for Earthquakes and Tsunamis) is a submarine cabled real-time seafloor surveillance infrastructure for earthquake activity at assumed focus region of mega-thrust earthquake around Japan. The original system DONET1 was constructed in To-Nankai earthquake focus region and twenty seafloor observatories are working in operation beginning in 2011 to contribute the earthquake and tsunami early warning program in Japan. Development of second seafloor network DONET2 was planned in 2010 to target Nankai earthquake focus region. This paper describes a decision making approach of DONET2 observation site arrangement based on the knowledge of DONET1 development and construction.
{"title":"Decision-making on seafloor surveillance infrastructure site for Earthquake and Tsunami monitoring in Western Japan","authors":"K. Kawaguchi, E. Araki, Masanori Hoshino, T. Yokobiki, H. Matsumoto, S. Nishida, Jin-Kyu Choi, T. Kimura, N. Takahashi, T. Baba, M. Nakano, Takeshi Nakamura, Y. Kaneda","doi":"10.1109/OCEANS-TAIPEI.2014.6964514","DOIUrl":"https://doi.org/10.1109/OCEANS-TAIPEI.2014.6964514","url":null,"abstract":"DONET (Dense Ocean-floor Observatory Network for Earthquakes and Tsunamis) is a submarine cabled real-time seafloor surveillance infrastructure for earthquake activity at assumed focus region of mega-thrust earthquake around Japan. The original system DONET1 was constructed in To-Nankai earthquake focus region and twenty seafloor observatories are working in operation beginning in 2011 to contribute the earthquake and tsunami early warning program in Japan. Development of second seafloor network DONET2 was planned in 2010 to target Nankai earthquake focus region. This paper describes a decision making approach of DONET2 observation site arrangement based on the knowledge of DONET1 development and construction.","PeriodicalId":114739,"journal":{"name":"OCEANS 2014 - TAIPEI","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131524838","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}
Pub Date : 2014-04-07DOI: 10.1109/OCEANS-TAIPEI.2014.6964389
Ruey‐Chang Wei, W. Chang, Chi-Fang Chen
Ocean ambient noise data were collected by underwater MACHO (MArine Cable Hosted Observatory) system, deployed by Central Weather Bureau, at northeastern sea of Taiwan from October of 2011 to March of 2012. With most rainfall of Taiwan in the area of measurement, the rain-generated underwater noise was studied in an attempt to estimate rainfall contribution by the correlation analysis with the acoustic data. Due to the intermittent nature of rain fall occurrence, significant rainfall events with extended period were extracted from the weather data measured at nearest Su-ao weather station, and then patched together to form a rainfall intensity time series. Linear regression between corresponding ocean ambient noise level time series of several frequencies and rainfall intensity data were performed, so the characteristic frequency for prediction can be decided. Duration of this study was divided into Fall, Winter, and Spring, then the statistics and distributions of ambient noise level at different frequencies and rainfall intensities were calculated, so that seasonal variations were also discussed.
{"title":"Estimation of rainfall contribution to ocean ambient noise in Northeastern Taiwan Sea","authors":"Ruey‐Chang Wei, W. Chang, Chi-Fang Chen","doi":"10.1109/OCEANS-TAIPEI.2014.6964389","DOIUrl":"https://doi.org/10.1109/OCEANS-TAIPEI.2014.6964389","url":null,"abstract":"Ocean ambient noise data were collected by underwater MACHO (MArine Cable Hosted Observatory) system, deployed by Central Weather Bureau, at northeastern sea of Taiwan from October of 2011 to March of 2012. With most rainfall of Taiwan in the area of measurement, the rain-generated underwater noise was studied in an attempt to estimate rainfall contribution by the correlation analysis with the acoustic data. Due to the intermittent nature of rain fall occurrence, significant rainfall events with extended period were extracted from the weather data measured at nearest Su-ao weather station, and then patched together to form a rainfall intensity time series. Linear regression between corresponding ocean ambient noise level time series of several frequencies and rainfall intensity data were performed, so the characteristic frequency for prediction can be decided. Duration of this study was divided into Fall, Winter, and Spring, then the statistics and distributions of ambient noise level at different frequencies and rainfall intensities were calculated, so that seasonal variations were also discussed.","PeriodicalId":114739,"journal":{"name":"OCEANS 2014 - TAIPEI","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131580874","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}
Pub Date : 2014-04-07DOI: 10.1109/OCEANS-TAIPEI.2014.6964578
Seong-Oh Kim, Y. Ock, J. Heo, Jong-Chun Park, Hee-sung Shin, Seung-Keon Lee
IMO(International Marine Organization) adopted the mandatory application of the EEDI(Energy Efficiency Design Index) for new ships in order to reduce the emissions of CO2(IMO, 2011). Added resistance, which is defined as an increased resistance of ships in waves, have a large effect on emissions of CO2. It is important that exact estimation of added resistance is essential for precise calculation of EEDI coefficient (MEPC 63rd session report). In the present study, CFD(Computational Fluid Dynamics) simulation using overset grid method is performed on KCS(KRISO Container Ship) hull form to predict added resistance for precise EEDI coefficient. Simulation results is compared to experimental result(Simonsen et al, 2008 [18]).
为了减少二氧化碳的排放，IMO(国际海事组织)对新船强制采用了EEDI(能源效率设计指数)(IMO, 2011)。附加阻力，即船舶在波浪中阻力的增加，对二氧化碳的排放有很大的影响。附加阻力的准确估计是精确计算EEDI系数的关键(MEPC第63届会议报告)。本文采用超置网格法对KCS(KRISO集装箱船)船体外形进行CFD(Computational Fluid Dynamics)仿真，以预测精确EEDI系数的附加阻力。将仿真结果与实验结果进行对比(Simonsen et al .， 2008[18])。
{"title":"CFD simulation of added resistance of ships in head sea for estimating energy efficiency design index","authors":"Seong-Oh Kim, Y. Ock, J. Heo, Jong-Chun Park, Hee-sung Shin, Seung-Keon Lee","doi":"10.1109/OCEANS-TAIPEI.2014.6964578","DOIUrl":"https://doi.org/10.1109/OCEANS-TAIPEI.2014.6964578","url":null,"abstract":"IMO(International Marine Organization) adopted the mandatory application of the EEDI(Energy Efficiency Design Index) for new ships in order to reduce the emissions of CO2(IMO, 2011). Added resistance, which is defined as an increased resistance of ships in waves, have a large effect on emissions of CO2. It is important that exact estimation of added resistance is essential for precise calculation of EEDI coefficient (MEPC 63rd session report). In the present study, CFD(Computational Fluid Dynamics) simulation using overset grid method is performed on KCS(KRISO Container Ship) hull form to predict added resistance for precise EEDI coefficient. Simulation results is compared to experimental result(Simonsen et al, 2008 [18]).","PeriodicalId":114739,"journal":{"name":"OCEANS 2014 - TAIPEI","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132809325","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}
Pub Date : 2014-04-07DOI: 10.1109/OCEANS-TAIPEI.2014.6964597
Jinghua Tao, Xu Jia, Jinlin Hou, J. Tao
As a unique structural system in the float-over installation, DSF supports topside weight in the load-out and tow process, and cushions collision loads of the topside and the barge in the mating process. Based on the float-over installation of LW3-1CEP topside, the paper makes deeply studies on DSF from many aspects, such as general layout, span change, DSU layout, special cap limit, space bound, member optimization, weight control and so on. And then this paper discusses a new type of DSF system with greater capability to support topside weight of up to 27,000 metric tons, meeting functional requirements of super-heavy topside float-over installation. The research of the new type of DSF will be a guide and reference for future heavier topside float-over installation.
{"title":"Research on the DSF for float-over of super-heavy topside in the South China Sea","authors":"Jinghua Tao, Xu Jia, Jinlin Hou, J. Tao","doi":"10.1109/OCEANS-TAIPEI.2014.6964597","DOIUrl":"https://doi.org/10.1109/OCEANS-TAIPEI.2014.6964597","url":null,"abstract":"As a unique structural system in the float-over installation, DSF supports topside weight in the load-out and tow process, and cushions collision loads of the topside and the barge in the mating process. Based on the float-over installation of LW3-1CEP topside, the paper makes deeply studies on DSF from many aspects, such as general layout, span change, DSU layout, special cap limit, space bound, member optimization, weight control and so on. And then this paper discusses a new type of DSF system with greater capability to support topside weight of up to 27,000 metric tons, meeting functional requirements of super-heavy topside float-over installation. The research of the new type of DSF will be a guide and reference for future heavier topside float-over installation.","PeriodicalId":114739,"journal":{"name":"OCEANS 2014 - TAIPEI","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132911815","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}
Pub Date : 2014-04-07DOI: 10.1109/OCEANS-TAIPEI.2014.6964458
C. Yun, N. Ko, Yongseon Moon, Hyun-Taek Choi
This paper describes a development of a broad band underwater acoustic transducer for Doppler Velocity Log(DVL). The transducer uses thickness vibration mode of a disk type piezoelectric(PZT) ceramic. Three types of transducers, each having different configuration of acoustic impedance matching layer and backing are composed. Transmitting voltage response(TVR), receiving voltage sensitivity(RVS) and bandwidth of the transmission for the three types of acoustic transducers are evaluated. The test shows that the transducer with the configuration of three matching layers and a lossy backing results the best performance among the three types. From the test results, the effects of the acoustic impedance matching layer and backing are discussed.
{"title":"Design and experiment of an acoustic transducer for underwater navigation","authors":"C. Yun, N. Ko, Yongseon Moon, Hyun-Taek Choi","doi":"10.1109/OCEANS-TAIPEI.2014.6964458","DOIUrl":"https://doi.org/10.1109/OCEANS-TAIPEI.2014.6964458","url":null,"abstract":"This paper describes a development of a broad band underwater acoustic transducer for Doppler Velocity Log(DVL). The transducer uses thickness vibration mode of a disk type piezoelectric(PZT) ceramic. Three types of transducers, each having different configuration of acoustic impedance matching layer and backing are composed. Transmitting voltage response(TVR), receiving voltage sensitivity(RVS) and bandwidth of the transmission for the three types of acoustic transducers are evaluated. The test shows that the transducer with the configuration of three matching layers and a lossy backing results the best performance among the three types. From the test results, the effects of the acoustic impedance matching layer and backing are discussed.","PeriodicalId":114739,"journal":{"name":"OCEANS 2014 - TAIPEI","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123987847","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}
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