2011 IEEE/OES 10th Current, Waves and Turbulence Measurements (CWTM)最新文献

{"title":"Accuracy and reliability of ocean radar WERA in beam forming or direction finding mode","authors":"T. Helzel, M. Kniephoff, L. Petersen, V. Mariette, N. Thomas","doi":"10.1109/CWTM.2011.5759518","DOIUrl":"https://doi.org/10.1109/CWTM.2011.5759518","url":null,"abstract":"This paper introduces the over-the-horizon radar technique optimized for oceanographic applications. The relation between radar range and operating frequency will be explained as well as the radar resolution which depends on the radar bandwidth. The accuracy in azimuth strongly depends on the number of used receive antennae and samples demonstrate the high accuracy that can be achieved. The oceanographic data output are provided in near real-time with an individually optimized integration time for currents (5 to 10 min) and wave data (20 to 30 min). This method results in very reliable and accurate ocean data with a reported data availability of more than 98 % within the last 3 years. This excellent reliability makes these kind of instruments a perfect tool for harbor and coastal management to optimize SAR and pollution drift monitoring.","PeriodicalId":345178,"journal":{"name":"2011 IEEE/OES 10th Current, Waves and Turbulence Measurements (CWTM)","volume":"5 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129181131","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":"Enabling quality assessment through web services","authors":"J. Fredericks, E. Terray, J. Bosch, Tony Cook, D. Symonds, G. Voulgaris","doi":"10.1109/CWTM.2011.5759535","DOIUrl":"https://doi.org/10.1109/CWTM.2011.5759535","url":null,"abstract":"Emerging technologies in web-based services have enabled the integration of global, interdisciplinary earth observations. These capabilities can provide an unprecedented opportunity to promote the establishment and adoption of standards for the delivery of information about sensor systems which can enable data quality assessment by disparate users. Machine-to-machine harvesting of data can either become a barrier to content (i.e., easy to get data but hard to determine lineage and provenance) or it can promote communication of critical metadata (i.e., easy to get data with fully described sensor and processing systems). In this contribution, we describe how Open-Geospatial Consortium (OGC) frameworks can enable web services with fully-described sensor systems, including processing lineage. Also presented here is an OGC Sensor Web Enablement (SWE) demonstration project describing the processing and sensor system used to measure real-time in situ currents and wave parameters.","PeriodicalId":345178,"journal":{"name":"2011 IEEE/OES 10th Current, Waves and Turbulence Measurements (CWTM)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131526461","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":"After 40 years, how are HF radar currents now being used?","authors":"D. Barrick","doi":"10.1109/CWTM.2011.5759514","DOIUrl":"https://doi.org/10.1109/CWTM.2011.5759514","url":null,"abstract":"The ability of coastal HF radars to map ocean surface currents was demonstrated in the early 70s at NOAA in the U.S. Since that time, there was a push to develop this technology into a useful, affordable tool that would fill a big gap: nothing else out there could map surface currents continuously over space and time, and the same holds true today. But who would use these data?","PeriodicalId":345178,"journal":{"name":"2011 IEEE/OES 10th Current, Waves and Turbulence Measurements (CWTM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115395590","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":"RiverRay ADCP: Performance of a shallow water phased array ADCP","authors":"R. Marsden, J. Gast, Frank Dumville","doi":"10.1109/CWTM.2011.5759561","DOIUrl":"https://doi.org/10.1109/CWTM.2011.5759561","url":null,"abstract":"Phased array ADCPs have been used for oceanography since the mid-1990's. Phased array technology for ADCPs allows the physical size of a low frequency ADCP to be significantly reduced by generating four acoustic beams from a single transducer. Until recently, acoustic phased arrays were built from individual transducer elements: this method did not allow construction at higher frequencies since the discrete array elements would be on the order of a millimeter in lateral and vertical dimensions, making the assembly of a larger transducer impractical. This problem was solved by dicing a single piezoelectric into small elements to produce a precision array. The RiverRay ADCP is the first phased array ADCP specifically designed for shallow water velocity profiling. In addition to the phased array transducer, it incorporates several unique features for use in shallow water, particularly for river discharge measurement. This paper discusses the RiverRay ADCP and its performance in the field.","PeriodicalId":345178,"journal":{"name":"2011 IEEE/OES 10th Current, Waves and Turbulence Measurements (CWTM)","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126317761","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 acoustic modeling to develop a hybrid H-ADCP configuration","authors":"S. J. Stamates","doi":"10.1109/CWTM.2011.5759564","DOIUrl":"https://doi.org/10.1109/CWTM.2011.5759564","url":null,"abstract":"The Port Everglades Shipping Channel (PESC) in Ft. Lauderdale, Florida is thought to be a pathway by which anthropogenic nutrients and pathogens reach the coastal ocean from inland waters. To quantify this, a flow measurement system was installed in the PESC. In planning this measurement system, conventional vertical and horizontal ADCP configurations were considered but found to be unsuitable for differing reasons. This motivated the development of a hybrid deployment configuration. A Teledyne-RDI 300 kHz H-ADCP was deployed near the surface with an 8.5 degree downward tilt so that measurement cells nearest to the instrument would record data from the upper water column while cells further from the instrument would record data from deeper depths. The PESC is often times vertically stratified and it was realized that this stratification could affect the data received from a system deployed in this manner. To estimate these effects, sound speed profiles taken in the PESC were used as input to an acoustic propagation model. This model simulated the acoustic paths from the instrument deployed at different angles. Analysis of these simulations enabled the selection of the optimal angle for deployment that allowed for the maximum profiling range while minimizing the effects of stratification on the acoustic path.","PeriodicalId":345178,"journal":{"name":"2011 IEEE/OES 10th Current, Waves and Turbulence Measurements (CWTM)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129127380","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":"ADCP data collected from a Liquid Robotics Wave Glider®","authors":"J. Mullison, D. Symonds, Neil Trenaman","doi":"10.1109/CWTM.2011.5759563","DOIUrl":"https://doi.org/10.1109/CWTM.2011.5759563","url":null,"abstract":"Liquid Robotics, Inc. (LRI) has developed an autonomous vehicle, the Wave Glider®, which utilizes wave energy for propulsion, Iridium® Satellite for command, control and data exfiltration and GPS satellite transmissions for positioning. The vehicle consists of a low-profile surface float outfitted with solar panels, energy storage and shore communication infrastructure and a subsurface wing located at approximately seven meters depth connected to each other by a sophisticated tether. The wing is designed to respond to the wave energy at its depth in such a way that it provides propulsion for the vehicle toward any location chosen by the operator. The wave energy thus harnessed by the vehicle can be used for locomotion to any point of interest as well as for station keeping (by driving in a tight circle) once that position is reached. Real time communication with the shore-based operator allows monitoring of platform's location and data gathered, commanding movement to a new position, or even complete repurposing of the mission. The capability of the Wave Glider® to accomplish its mission in a variety of environments with a variety of mission profiles is now well proven. In addition, the Wave Glider® is of course capable of carrying a variety of sensor payloads. LRI and Teledyne RD Instruments (TRDI) have now partnered to provide current profile measurements from the vehicle. An initial encouraging field test in 2009 showed the feasibility sufficiently to merit further work, though there was some indication that asymmetric motion of the surface float (it tends to skate on wave faces in some sea states) combined with low resolution GPS sampling could be biasing the velocity measurements. This led to additional testing of a Wave Glider® equipped with an ADCP, higher resolution GPS and an Inertial Motion Unit in 2010. Once the extensive integration project was completed sufficiently, a new field campaign was launched for comparison of the new, more integrated Wave Glider® ADCP measurements with those of a bottom mounted Workhorse ADCP that was deployed as an independent reference. The mission profile for this field campaign included programming the Wave Glider® to circle between the shallow water in which the reference ADCP was deployed to the deeper water of a submerged canyon. In this way measurements could be taken in shallow water, where bottom tracking capability could be effectively relied upon to remove platform motion, and in deeper water where the bottom was out of range and the relative motion of the platform removed by other means. Given the change in depth, there is no reason to assume the reference ADCP measurements are valid in the deeper water. However, comparison of the reference instrument in the shallow water with the relative velocity removed by bottom track and by the other methods can prove the utility of the other methods, and continuity of measurement between the shallow, referenced and deep, unreferenced regimes would indicate","PeriodicalId":345178,"journal":{"name":"2011 IEEE/OES 10th Current, Waves and Turbulence Measurements (CWTM)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128354838","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":"Horizontal ADCP measurements of waves and currents in the very nearshore","authors":"M. D. de Schipper, R.C. de Zeeuw, S. de Vries, M. Stive, J. Terwindt","doi":"10.1109/CWTM.2011.5759545","DOIUrl":"https://doi.org/10.1109/CWTM.2011.5759545","url":null,"abstract":"Hydrodynamic measurements of the very nearshore are valuable, but often difficult to obtain. Large amounts of bubbles due to wave breaking and complex installation complicate the use of acoustic instruments in this zone. This paper presents measurements obtained by a horizontal looking ADCP (hADCP) installed in the very nearshore to measure waves and wave currents. The observations are separated into the various timescales ranging from high frequency orbital motion to very low frequency oscillations and mean flow. Results reveal the presence of significant very low frequency oscillations and the potential of a hADCP to capture wave transformation in the nearshore.","PeriodicalId":345178,"journal":{"name":"2011 IEEE/OES 10th Current, Waves and Turbulence Measurements (CWTM)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128261492","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":"Noise in Ice-Tethered Profiler and McLane Moored Profiler velocity measurements","authors":"F. Thwaites, R. Krishfield, M. Timmermans, J. Toole, A. Williams","doi":"10.1109/CWTM.2011.5759553","DOIUrl":"https://doi.org/10.1109/CWTM.2011.5759553","url":null,"abstract":"In order to measure current profiles, and most recently, turbulent fluxes, moored profiling instrument have been equipped with acoustic travel-time current sensors. Noise in the measured currents has exceeded expectations. A customized Falmouth Scientific acoustic current sensor on a McLane Moored Profiler (MMP) has a standard deviation of measured velocity that is 4.4% of the profiler velocity in still water and a modified Modular Acoustic Velocity Sensor (MAVS) on an MMP and an Ice-Tethered Profiler (ITP) has a standard deviation of 4.6% of profiler velocity. Both of these sensors measure velocity along four acoustic paths and the water velocities were computed neglecting their downstream paths.","PeriodicalId":345178,"journal":{"name":"2011 IEEE/OES 10th Current, Waves and Turbulence Measurements (CWTM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131797921","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 mapping of ocean surface currents and directional wave spectra","authors":"D. Trizna","doi":"10.1109/CWTM.2011.5759526","DOIUrl":"https://doi.org/10.1109/CWTM.2011.5759526","url":null,"abstract":"A coherent marine radar with 3-m resolution has been developed that measures the radial component of the orbital wave velocity of ocean waves, as well as the mean radial ocean surface velocity. This radar provides a direct measure of the ocean wave spectrum by means of 3D-FFT processing of a sequence of radial velocity images collected at a 0.8 Hz image rate. Typically, 512 images are used, covering periods of the order of ten minutes, allowing a modest number of wave groups to be measured. The mean radial velocity map is obtained by a superposition of all radial velocity images collected, allowing wave patterns to blend to the mean, resulting in a map of mean currents. A pair of such radars operated at a coastal site, separated by a few hundred meters along the coastline, could allow the combination of radial components to be combined into a mean current vector field. Results of an experiment run during the offshore passage of Hurricane Ida in 2009 are presented, collected at the U.S. Army Corps of Engineers Field Research Facility, Duck, N.C.","PeriodicalId":345178,"journal":{"name":"2011 IEEE/OES 10th Current, Waves and Turbulence Measurements (CWTM)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121366027","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":"Field testing of a new ADCP","authors":"J. Mullison, P. Wanis, D. Symonds","doi":"10.1109/CWTM.2011.5759531","DOIUrl":"https://doi.org/10.1109/CWTM.2011.5759531","url":null,"abstract":"Since its introduction in 1992, the Teledyne RDI Instruments (TRDI) Workhorse ADCP has become ubiquitous, with literally thousands of systems deployed in nearly every body of water on earth. While the measurement itself remains relatively unchanged, in the intervening years the use of the measurements has changed to an extraordinary extent. Originally a novel way to measure currents sorely in need of proving and acceptance by the research community, ADCP measurements are now the de facto standard for current measurement. What began as a useful tool for academic research continues in that role, but has also become standard equipment for real time decision making. ADCPs are now routinely used to measure river discharge and to aid flood control engineers in managing river levels. Since a terrible accident occurred in Tampa Bay, ADCPs now provide current information in near real-time to the pilots and captains of large vessels as they ply many of the world's major ports and waterways. Because offshore platforms cannot safely operate in the large currents of the Gulf of Mexico's Loop Current and the Eddies it generates, ADCPs play a critical role on all offshore platforms in the deep Gulf of Mexico. The presence and trajectories of these high Gulf of Mexico currents are forecast with great accuracy, the ADCPs real utility comes in determining when they are no longer affecting the rig. ADCPs provide information on an hourly basis in near real time from the TAO/TRITON array for climate forecasting. Returned Signal Strength Intensity data, originally provided strictly as an ancillary quality control parameter, has developed into a useful tool for studies as diverse as the diel migration of zooplankton to aid in creating optimal harbor designs based on sediment transport patterns in the area.","PeriodicalId":345178,"journal":{"name":"2011 IEEE/OES 10th Current, Waves and Turbulence Measurements (CWTM)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132583241","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}