OCEANS 2019 MTS/IEEE SEATTLE最新文献

{"title":"Integrated Monitoring Systems for Coastal Communities","authors":"R. Flagg, M. Otokiak, M. Hoeberechts, Lucianne M. Marshall","doi":"10.23919/OCEANS40490.2019.8962781","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962781","url":null,"abstract":"With approximately 40 percent of the world's population living within 100 km of the coast, it is critical that the ocean environment upon which these people depend be persistently monitored. Fortunately, coastal communities are ideally situated to take the leading role in this effort by leveraging their knowledge and understanding of the surrounding environment and by taking advantage of existing community infrastructure to support a range of complementary monitoring systems. Ocean Networks Canada (ONC) operates ocean observatories on the west and east coasts of Canada and the Arctic and continuously gathers data in real-time for scientific research that helps communities, governments, and industry make informed decisions about the future. ONC is best known for its NEPTUNE and VENUS cabled observatories located off-shore southern British Columbia, and for the Oceans 2.0 data management system that supports ocean sensor health monitoring and troubleshooting, asset management, data capture, QA/QC, metadata, data delivery, data products, and web services. Building on the experience and expertise garnered from the installation and maintenance of VENUS and NEPTUNE, and on the data management foundation provided by Oceans 2.0, Ocean Networks Canada has advanced its capacity to monitor the ocean. ONC's world leading understanding of cabled community observatories and community-led monitoring programs leverages advancements in mobile oceanographic and meteorological instruments by making use of purpose-built mobile application software. The Cambridge Bay, NU observatory has provided a number of instrument manufacturers with opportunities to test and demonstrate their technologies under extreme Arctic conditions while simultaneously providing a wide range of persistent, real-time data to both the global science and local Arctic communities. Since the installation in 2012, the growing use of the Cambridge Bay observatory physical infrastructure and data has increased reliance on its continued successful operation and increased demand on its capabilities. In fact, support for this particular community observatory continues to grow with Cambridge Bay residents providing logistic assistance for observatory maintenance, participating in outreach and formal learning activities, and, more recently, collecting critical, winter-time data on snow depth and ice thickness. Its success enabled the expansion of a number of community observatories across the BC coast, as part of ONC's Smart Ocean SystemsTM program. Meanwhile, data collected by community members themselves (commonly referred to as “citizen science”) is a concept that continues to evolve with changing technology, data demands, and collection techniques. This method has remarkable potential in coastal communities, as the people who live there are, without question, the best suited to be collecting data in the field. Their understanding of the local environment and the risks and challenges of working in the","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124439842","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-Range Maritime Communications through a Multi-Link Ensemble","authors":"Steven Jones, R. Awadallah, P. Chimento, T. Hanley, Jeramy Hansen, R. Nichols","doi":"10.23919/OCEANS40490.2019.8962745","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962745","url":null,"abstract":"We consider the ability to support communications for beyond line of site (BLOS) maritime applications through an ensemble of communication link modalities. While satellite communications is often used for this purpose it can be costly in terms of airtime. As anticipated no one modality is expected to enable adequate performance; however, we have modelled the performance of an ensemble of links which shows promise in providing operationally-relevant data rates. The link paths investigated include HF (skywave and surface wave), ducting, meteor burst, and troposcatter.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115760909","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":"Evaluation of Surrogate Models for Multi-fin Flapping Propulsion Systems","authors":"K. Viswanath, Alisha Sharma, Saketh Gabbita, J. Geder, R. Ramamurti, M. Pruessner","doi":"10.23919/OCEANS40490.2019.8962674","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962674","url":null,"abstract":"The aim of this study is to develop surrogate models for quick, accurate prediction of thrust forces generated through flapping fin propulsion for given operating conditions and fin geometries. Different network architectures and configurations are explored to model the training data separately for the lead fin and rear fin of a tandem fin setup. We progressively improve the data representation of the input parameter space for model predictions. The models are tested on three unseen fin geometries and the predictions validated with computational fluid dynamics (CFD) data. Finally, the orders of magnitude gains in computational performance of these surrogate models, compared to experimental and CFD runs, vs their tradeoff with accuracy is discussed within the context of this tandem fin configuration.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117109052","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":"Pitch and Depth Keeping of Moored-type Underwater Acoustic Array System","authors":"Sukmin Yoon, Chong-moo Lee, Kihun Kim, S. Byun","doi":"10.23919/OCEANS40490.2019.8962554","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962554","url":null,"abstract":"This paper introduces the operation method of KAAS (KRISO acoustic array system) developed in South Korea. KAAS is a moored-type underwater acoustic array system for the research of signal processing technology that uses array sensors to detect and classify underwater sound sources and targets. The underwater platform with the hydrophone array and the acoustic projector should be kept horizontal during signal transmission and reception. For this, the weathervaning mooring method and the stabilizers are applied to maintain the horizontal even keel of platform without a propulsion system. And the buoyancy control units are equipped to control the total buoyancy and the horizontal balance. In the weathervaning mooring method, the effects of the current on the platform are analyzed and the results from varying the length of the mooring cable are simulated. The results of comparative analysis of simulations and pier test are discussed.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117119923","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":"Nonlinear WEC Optimized Geometric Buoy Design for Efficient Reactive Power Requirements","authors":"D. Wilson, R. Robinett, G. Bacelli, O. Abdelkhalik, W. Weaver, R. Coe","doi":"10.23919/OCEANS40490.2019.8962670","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962670","url":null,"abstract":"This paper presents a nonlinear geometric buoy design for Wave Energy Converters (WECs). A nonlinear dynamic model is presented for an hour glass (HG) configured WEC. The HG buoy operates in heave motion or as a single Degree-of-Freedom (DOF). The unique formulation of the interaction between the buoy and the waves produces a nonlinear stiffening effect that provides the actual energy storage or reactive power during operation. A Complex Conjugate Control (C3) with a practical Proportional-Derivative (PD) controller is employed to optimize power absorption for off-resonance conditions and applied to a linear right circular cylinder (RCC) WEC. For a single frequency the PDC3 RCC buoy is compared with the HG buoy design. A Bretschneider spectrum of wave excitation input conditions are reviewed and evaluated for the HG buoy. Numerical simulations demonstrate power and energy capture for the HG geometric buoy design which incorporates and capitalizes on the nonlinear geometry to provide reactive power for the single DOF WEC. By exploiting the nonlinear physics in the HG design simplified operational performance is observed when compared to an optimized linear cylindrical WEC. The HG steepness angle $alpha$ with respect to the wave is varied and initially optimized for improved energy capture.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117270189","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":"Design and implementation of a real-time underwater acoustic telemetry system for fish behavior study and environmental sensing","authors":"Yang Yang, Jayson J. Martinez, Jun Lu, H. Hou, Z. Deng","doi":"10.23919/OCEANS40490.2019.8962593","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962593","url":null,"abstract":"Underwater acoustic telemetry is an important tool for studying the behavior of aquatic animals and assessing the environmental impact of man-made structures such as hydropower turbines. However, the current design of acoustic telemetry systems lack the ability to transmit collected data continuously in real-time and requires manual retrieval of the recorded measurements, leading to a long delay of data retrieval, high operational cost associated with manpower as well as safety risk for the operators. In addition, there is no efficient way to monitor the status of the acoustic telemetry system, including acoustic transmitters and receivers. For example, if multiple receivers in an array fail, the detection efficiency could be significantly reduced. Herein, we developed a cloud-based, real-time underwater acoustic telemetry system that can be used to estimate behavior or survival of tagged aquatic animals and monitor environmental parameters in near-real-time (< 2 hours). The system incorporates microcontrollers and integrated circuits to create real-time data communication and processing units with a cloud-based service that processes the transmitted data stream to derive behavior and survival information of the tagged animals.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125139011","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":"Matched-filter mismatch loss from within-pulse time-varying platform motion","authors":"D. Abraham, M. Demaio","doi":"10.23919/OCEANS40490.2019.8962599","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962599","url":null,"abstract":"In active sonar, own-Doppler nullification is used to remove the effect of motion of the source and receiver platforms. The process generally assumes a constant radial velocity throughout pulse transmission and during echo reception. When the platform motion does not satisfy the constant-radial-velocity assumption, the matched filter suffers a mismatch loss from time-varying own-Doppler (TVOD). The average TVOD signal-to-noise-ratio loss for velocity variations represented by a Gaussian random process is derived and approximated to show its dependence on the velocity variance, pulse duration and center frequency. The results provide a quantitative assessment of the common lore that platform velocity variations arising from wave motion are negligible for low frequencies or short pulses, but can produce significant losses as pulse duration and frequency or velocity variation increase.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125862653","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":"Toward Maritime Robotic Simulation in Gazebo","authors":"B. Bingham, Carlos E. Agüero, Michael McCarrin, J. Klamo, Joshua Malia, Kevin Allen, Tyler Lum, Marshall Rawson, Rumman Waqar","doi":"10.23919/OCEANS40490.2019.8962724","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962724","url":null,"abstract":"Simulation plays an important role in the development, testing and evaluation of new robotic applications, reducing implementation time, cost and risk. For much of the robotics community, the open-source Gazebo robot simulator has emerged as the de facto standard environment for prototyping and testing robotic systems. While Gazebo offers strong support for terrestrial, aerial and space robotics applications, less support is available for marine applications involving vehicles at and below the water surface. To address this deficiency, we present the Virtual RobotX (VRX) simulation, a general purpose open-source development and testing tool, based on Gazebo, capable of approximating the behavior of unmanned surface vessels operating in complex ocean environments. We highlight the application of these capabilities using the VRX challenge reference implementation, a new simulation-based robot competition designed to complement the physical Maritime RobotX Challenge.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123464739","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":"Improving downlooking SAS resolution with transmitter spatial diversity","authors":"T. Marston, S. Kargl, Daniel S. Plotnick, K. Williams","doi":"10.23919/OCEANS40490.2019.8962536","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962536","url":null,"abstract":"Various low frequency down-looking SAS systems have been designed to produce sub-sediment volumetric imagery for the purpose of detecting unexploded ordnance (UXO), cables, pipelines, or other buried objects. These systems create three-dimensional images by combining an across-track physical array with an along-track synthetic aperture to form a down-looking planar array. The low frequencies used to penetrate the sediment necessitate wide physical arrays to achieve useful resolution in the across-track dimension. Space, cost, and mechanical design limitations place a practical upper bound on the physical array length. An alternative method for resolution enhancement is to use transmitter spatial diversity. In the current paper, simulations comparing a dual-transmitter and single-transmitter design are conducted using the design parameters of the Multi-Sensor Towbody (MuST) system developed at APL-UW. The MuST system has a downward looking array composed of multiple EdgeTech Buried Object Scanning Sonar (eBOSS) panels aligned in the across-track dimension. The system has three separate transmitters: one transmitter located near the middle of the array and two transmitters at opposing ends of the array. The MuST system was designed to have two different transmit modes: one in which the active transmitter alternates between opposing ends of the array, and one in which the active transmitter is always near the center of the array. Both point target and bistatic rigid model simulations for these two transmitter configurations indicate that by using the configuration with alternating transmitters the across-track resolution can be increased.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125557983","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":"Correlating Water Quality and Profile Data in the Florida Keys","authors":"Alejandro Torres, G. Reis, Jeff Absten, Henry O Briceno, Leonardo Bobadilla, Ryan N. Smith","doi":"10.23919/OCEANS40490.2019.8962646","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962646","url":null,"abstract":"Aquatic ecosystems present complex structures susceptible to changes that can cause adverse effects in the water. These problems have turned the attention of researchers to understand them, and possibly take action to prevent further damages. This interest led to the accumulation of large amounts of data with limited personnel and resources to analyze it. An example of this is the collection of data in South Florida for 25 years by Florida International University. By making use of a depth profile and surface water quality data sets collected in the same location at the same time, a methodology is proposed to correlate these two data sets. By using Machine Learning, we represented depth profiles with coefficients followed by clustering analysis. Similarly, a water surface chemical data set was clustered using k-means. We then used statistical methods to test the connection between these two data sets.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116453217","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}