2012 Oceans最新文献

{"title":"Bloom and toxin producing algae in Virginia tidal rivers","authors":"H. Marshall, T. Egerton","doi":"10.1109/OCEANS.2012.6404820","DOIUrl":"https://doi.org/10.1109/OCEANS.2012.6404820","url":null,"abstract":"A diverse representation of algal species are common bloom producers in the tidal waters of Virginia tributaries that enter Chesapeake Bay. In the lower more saline regions of these rivers dinoflagellates are the major bloom producers. Their increased abundance and occurrence generally follows the spring diatom bloom and continues into summer and autumn. These common bloom producers include the diatoms Skeletonema potamos, Skeletonema costatum, Cerataulina pelagica, and Leptocylindrus minimus, plus the dinoflagellates Akashiwo sanguinea, Cochlodinium polykrikoides, Heterocapsa rotundata, Heterocapsa triquetra, Prorocentrum minimum, and Scrippsiella trochoidea. Of these dinoflagellates the major bloom producer in regions of the lower York and James rivers is Cochlodinium polykrikoides. Also occurring in these downstream waters are the recognized toxin producers Alexandrium monilatum, Chattonella subsalsa, and Karlodinium veneficum. In contrast, the tidal freshwater regions of these rivers more commonly would produce cyanobacteria blooms, including those by Microcystis aeruginosa.","PeriodicalId":434023,"journal":{"name":"2012 Oceans","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127902933","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":"Using Twitter to define human uses for the MSP process","authors":"S. Stewart, S. Myers","doi":"10.1109/OCEANS.2012.6405140","DOIUrl":"https://doi.org/10.1109/OCEANS.2012.6405140","url":null,"abstract":"Many of the geospatial data sets used in the MSP process already exist or can be compiled with minimal effort and coordination, however the lack of data representing human use, or the socioeconomic dimension of coastal and marine resources, is well documented and accepted by MSP planners. Called the “missing layer”, the human dimension of the marine environment has been used only sparingly in the MSP process generally, and even less in the GIS-based decision support systems that the MSP process relies on. In its previously referenced MSP report, the IOC states that “The human dimensions of the marine environment are widely recognized as important to include and integrate into decision-making. However, there are few layers of socio-economic information that one might combine with the biophysical in, for example, spatial suitability analyses for the establishment of a marine protected area.” 1 This paper will discuss a software application and methodology that uses social microblog (Twitter) feeds to define human uses of the coastal and marine environments and how this data can be used by MSP planners in their GIS-based decision support systems.","PeriodicalId":434023,"journal":{"name":"2012 Oceans","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131567601","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":"Channel models for underwater vector transducer communication systems","authors":"C. Chen, A. Abdi","doi":"10.1109/OCEANS.2012.6404953","DOIUrl":"https://doi.org/10.1109/OCEANS.2012.6404953","url":null,"abstract":"Vector transducers generate or measure signals in the vector components of the acoustic field. Examples of the vector components are acoustic particle velocity and acoustic particle acceleration. In recent years underwater communication schemes using vector projectors as transmitters and vector sensors as receivers have been proposed. Therefore the need for characterization of the vector components of the acoustic field as efficient communication channels has emerged. In this paper we present two vector-field channel models which are suitable for two different multipath shallow water channels. Channel correlations and channel powers are studied in detail for each model, and closed-form expressions are derived in terms of the physical parameters of the channel. The results can serve as useful tools and metrics for communication system design using underwater acoustic vector transducers. They are also useful for estimating channel parameters such as angle spreads, angle of departures or angle of arrivals using vector transducers.","PeriodicalId":434023,"journal":{"name":"2012 Oceans","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130951945","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":"Complexity of near-bottom ocean currents in the northern Gulf of Mexico from a sea-bed ADCP","authors":"R. Crout, A. Brown, J. Krumm, P. Leung, Chunyan Li","doi":"10.1109/OCEANS.2012.6405123","DOIUrl":"https://doi.org/10.1109/OCEANS.2012.6405123","url":null,"abstract":"The oceanography of the northern Gulf of Mexico is complex. The Loop Current dominates the eastern half of the Gulf and a-periodically shed anti-cyclonic Loop Eddies that move into the western Gulf of Mexico. Wind-generated inertial waves move throughout the water column, carrying surface energy to depth. Stronger inertial currents associated with storm events, including cold front passages. Energy from tropical cyclone winds has been shown to impact near-bottom currents in water nearly two kilometers deep. Topographic Rossby Waves (TRWs), apparently generated by interactions associated with Loop Current and Loop Eddy processes, travel through the northern Gulf of Mexico and accelerate near-bottom currents. Current profile data from a bottom-mounted acoustic Doppler current profiler (ADCP) at 1300 meters depth in Green Canyon Block 645, south of the Atchafalaya Bay in Louisiana, are analyzed to investigate these phenomena. The seabed mounted 75 kHz ADCP was installed in June 2005 in response to a Notice to Lessees by the Bureau of Ocean Energy Management to collect data to insure the safety of drilling and production platforms. The innovative design, supplying power and recovering data from the ADCP via a tether, allows almost continuous receipt of data. The 75 kHz ADCP collects data in 20 meter bins to 500 meters above the ocean bottom at 20 minute intervals. As with all current profile data required by the NTL, the data are transmitted to the National Data Buoy Center (NDBC) where they are quality controlled and transmitted to the world's numerical prediction centers. Copies of the raw binary data and the quality controlled data are maintained at NDBC. Statistical and spectral analysis indicates a complex current structure temporally and vertically. Yearly averaged currents are approximately 5 cm/s from May 2005 through May 2010. At 1200 meters, the yearly averaged data range between 3.8 and 5.0 cm/s. The spectral analysis indicates that energy at 1000 and 1200 meter depths are dominated by processes near the inertial frequency (26.08 hours) and in the 17-20 day band that is related to Topographic Rossby Waves (TRWs). At 1000 meters, the energy in the two bands is approximately equal. Energy in the TRW frequency band exceeds that in the inertial frequency band at 1200 meters depth. Although the inertial currents are obvious in the data record, they weaken with depth. Individual time series are investigated to determine the impact of Loop Current Eddies and Gulf of Mexico hurricanes Katrina, Rita, Gustav, and Ike. Periodic currents at approximately 20-day intervals are obvious in the time series data following Loop Eddy generation. A common Loop Eddy path following eddy shedding is near the Green Canyon 645 site. Time series records show intense near-bottom currents. The highest speed currents at this location, exceeding 35 cm/s are associated with the passage of nearby Loop Eddies. Hurricanes also pass near the Green Canyon site and the near bo","PeriodicalId":434023,"journal":{"name":"2012 Oceans","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132820289","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 and visual instrumentation for survey of manganese crusts using an underwater vehicle","authors":"B. Thornton, A. Bodenmann, A. Asada, T. Sato, T. Ura","doi":"10.1109/OCEANS.2012.6404789","DOIUrl":"https://doi.org/10.1109/OCEANS.2012.6404789","url":null,"abstract":"This paper describes the application of acoustic and visual instruments developed to survey the volumetric distribution of manganese crusts from an underwater vehicle. The instruments consist of an acoustic device, used to measure the thickness manganese crust layers, and a visual mapping system that generates three-dimensional (3D) color reconstructions of the seafloor. The information obtained by these sensors is processed to automatically identify areas of exposed crust using the 3D reconstructions, and determine the thickness of the crusts based on the acoustic measurements to measure the volumetric distribution of manganese crusts. Continuous measurements of crust distribution were achieved for the first time using the instruments described during sea trials performed at #5 Takuyo seamount using the remotely operated vehicle Hyper-Dolphin.","PeriodicalId":434023,"journal":{"name":"2012 Oceans","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131267188","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":"3D path planning for AUV based on circle searching","authors":"Zheping Yan, Yufei Zhao, Tao Chen, Chao Deng","doi":"10.1109/OCEANS.2012.6404849","DOIUrl":"https://doi.org/10.1109/OCEANS.2012.6404849","url":null,"abstract":"An approach of 3D path planning for AUV on the basis of virtual terrain and thread map is proposed. The virtual terrain is constructed to predigest the 3D search space, transforming the 3D path planning to 2D path planning. Then, the thread map is made for unification of hostile threat and terrain. To obtain standout expansibility, an improved A* algorithm based on circle searching is applied for path search. Simulation results illustrate the proposed approach is simple, and fast, and the path posed is safe for trail.","PeriodicalId":434023,"journal":{"name":"2012 Oceans","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133759138","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":"Simulation of HF radar cross sections for swell contaminated seas","authors":"Chengxi Shen, E. Gill, Weimin Huang","doi":"10.1109/OCEANS.2012.6404836","DOIUrl":"https://doi.org/10.1109/OCEANS.2012.6404836","url":null,"abstract":"Based on HF bistatic models for the first- and second-order ocean cross sections developed earlier, a new monostatic cross section model for swell contaminated seas is proposed. The methodology of modelling is to incorporate a Wallop wave spectrum to represent the swell portion while describing the wind wave part with a typical Pierson-Moskowitz spectrum. Then, it is assumed that the total ocean surface is zero-mean Gaussian, and the general expression for the monostatic radar cross section still holds for the combined swell-wind wave spectrum. Simulated results are provided and are seen to be highly consistent with real Doppler spectra. This suggests the contamination of the swell component could be removed with refined inversion algorithms.","PeriodicalId":434023,"journal":{"name":"2012 Oceans","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115376974","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":"Coherent marine radar measurements of directional wave spectra using vertically polarized antennas","authors":"D. Trizna","doi":"10.1109/OCEANS.2012.6404904","DOIUrl":"https://doi.org/10.1109/OCEANS.2012.6404904","url":null,"abstract":"A coherent marine radar has been developed for imaging ocean wave orbital wave velocity wave patterns. A NOPP program, Roadmap: Technologies for Cost Effective, Spatial Resource Assessments for Offshore Renewable Energy, has helped finance recent ISR studies. This new coherent radar provides a direct measurement of ocean wave orbital wave velocity without relying on a modulation transfer function (MTF) that has been used with previous systems that map radar echo intensity. The latter approach is prone to error due to environmental dependencies of the MTF, particularly when winds blow into incoming waves, which then produces an enhanced echo strength that is misinterpreted by the MTF scaling as due to larger wave slopes and heights. With this new direct measurement of orbital wave velocity, directional ocean wave spectra can be measured unambiguously, and deterministic ocean wave height fields that can be mapped for real-time input into wave forecasts for ship motion response applications. Results of experiments conducted at the USACE pier in Duck, NC, during the passage of Hurricane Irene are presented, showing the effect of using vertically polarized antennas, minimizing wave breaking effects for wave heights above 2.5 m.","PeriodicalId":434023,"journal":{"name":"2012 Oceans","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124343481","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":"Environmental Protocols Framework for baseline and monitoring studies for the ocean renewable energy industry","authors":"J. Klure, S. Kopf","doi":"10.1109/OCEANS.2012.6405044","DOIUrl":"https://doi.org/10.1109/OCEANS.2012.6405044","url":null,"abstract":"The overarching goal of the Environmental Protocols Framework (Framework) is to describe a clear, consistent process for regulators and industry to follow when designing environmental baseline and post-installation monitoring studies for proposed wave, tidal and offshore wind projects in the U.S, thus reducing time and uncertainty associated with project development. The project team evaluated all stressor-receptor interactions and developed a simple set of criteria to select a set of interactions that provide the most meaningful evaluation of the Framework for each technology type. Design and application of the Framework resulted in different sets of priority issues for each technology type. Case studies of ocean renewable energy projects verified the proof of concept and demonstrated the applicability of the Framework to both real and hypothetical projects. Finally, implementation of this project showed the protocols are adaptable enough to apply to different ocean renewable energy technologies, yet specific enough to be useful for a single project at a single location.","PeriodicalId":434023,"journal":{"name":"2012 Oceans","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114564863","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":"Development of 8m long range imaging technology for generation of wide area colour 3D seafloor reconstructions","authors":"A. Bodenmann, B. Thornton, S. Hara, K. Hioki, M. Kojima, T. Ura, M. Kawato, Y. Fujiwara","doi":"10.1109/OCEANS.2012.6405002","DOIUrl":"https://doi.org/10.1109/OCEANS.2012.6405002","url":null,"abstract":"This paper introduces a mapping device capable of recording seafloor photos from altitudes of up to 8m, which can be used to build colour 3D reconstructions. Data recorded at sea are shown and the results after processing with two different methods for 3D reconstruction are introduced and compared.","PeriodicalId":434023,"journal":{"name":"2012 Oceans","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114717747","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}