OCEANS 2019 MTS/IEEE SEATTLE最新文献

{"title":"Towards a Real Time Obstacle Detection System for Unmanned Surface Vehicles","authors":"M. Sorial, Issa Mouawad, E. Simetti, F. Odone, G. Casalino","doi":"10.23919/OCEANS40490.2019.8962685","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962685","url":null,"abstract":"Environment perception plays a vital role in autonomous systems. Different sensory channels are exploited to capture a rich and a dynamic grasp of the surrounding to enable safe and efficient navigation. In this work, scene understanding in maritime environments is tackled using an obstacle detection and tracking procedure based on a video camera and a LIDAR (range sensor). We rely on state-of-the-art object detection CNN (Convolutional neural network) YOLO to detect obstacles in the image plane and we propose an efficient object tracking procedure to track objects across frames. LIDAR point clouds are used to locate obstacles in the world reference frame and thus, to derive a scene map with the obstacles and their headings which is used as an input to a path planning algorithm. the procedure is tested using data acquired from an unmanned surface vessel and typical metrics in object detection and tracking communities are used to evaluate our method. The results demonstrate improvement we achieve over the object detector baseline and other similar online tracking methods.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"1 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":"129825662","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":"Does the Hood Canal Bridge traffic noise affect migrating steelhead smolts?","authors":"Xiaoqin Zang, Jayson J. Martinez, Jun Lu, P. Titzler, Z. Deng","doi":"10.23919/OCEANS40490.2019.8962877","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962877","url":null,"abstract":"Recent research conducted by NOAA's Manchester Research Laboratory has provided strong evidence of a substantial migration interference and increased mortality risk of steelhead smolts associated with the Hood Canal Bridge, which drives the need to investigate the sound and vibration generated by the vehicles crossing the bridge. A month-long monitoring of in-water sound pressure and the vibration of the bridge pontoons was performed at the Hood Canal Bridge by three sets of autonomous sound and vibration recording systems deployed along the bridge. At each deployment site, sound pressure in water was recorded by a hydrophone submerged three meters under water, and the vibration of the bridge pontoon was recorded by an array of three orthogonally mounted single-axis accelerometers. Both sound pressure and acceleration data were analyzed and compared to the threshold levels suggested by previous studies. Results show that the observed sound pressure levels and particle accelerations are strongly correlated with traffic volume across the bridge, and particle accelerations occasionally exceeded the threshold levels that could elicit the avoidance behavior of juvenile salmon. It is concluded that the Hood Canal Bridge traffic noise can potentially affect migrating salmonids due to the intense particle accelerations caused by the bridge pontoons in water.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"28 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":"128776659","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":"A Depth-Correlation Method for Velocity Inversion of Internal Soliton Waves","authors":"Yongfei Li, Hangfang Zhao","doi":"10.23919/OCEANS40490.2019.8962642","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962642","url":null,"abstract":"This paper proposes a depth-correlation method for velocity inversion of internal soliton waves (ISWs). ISWs can cause perturbation of acoustic field when propagating along acoustic path, which can be represented by coupled modes. According to Dyson Series, the coupling frequency is related to the velocity of ISWs, and the vertical structures of acoustic perturbation spectrum at positive and negative coupling frequencies are consistent with the mode depth function of a pair of coupled modes, respectively. This information can be used to estimate the velocity of ISWs by a depth-correlation method. There are two cases in simulation: (1) constant velocity; (2) time-varying velocity. The validity of the method is verified by simulation results.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"66 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":"128611157","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":"How to Fly an Autonomous Underwater Glider to Measure an Internal Wave","authors":"Jasmin B. T. McInerney, A. Forrest, S. Schladow, J. Largier","doi":"10.23919/OCEANS40490.2019.8962407","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962407","url":null,"abstract":"Internal waves are ubiquitous features of lakes and oceans, significantly contributing to vertical mixing across large areas, driving gas, nutrient, sediment, and heat exchange between deep and surface waters. Traditionally moorings have been used to sample internal wave fields; providing good temporal data but limited spatial information. More recently, buoyancy-driven autonomous underwater vehicles (aka gliders) have enabled additional characterization of internal waves. Gliders are capable of travelling large distances over periods ranging from days to months, some yo-yoing to depths in excess of 1000 m, making them a promising tool for internal wave observation that better resolve spatial variability of these phenomena. They have been used to characterize mixing from internal waves in multiple ocean locations (e.g. the South China Sea, the Pacific Ocean off the California Coast, the Tasman Sea, and the Faroe Bank Channel) and several deep lakes (e.g. Lake Tahoe, Lake Geneva and Lake Superior). To date no optimal method to implement gliders to measure internal wave characteristics has been determined, although different research groups have experimented with several approaches. Previously employed approaches include using a glider as a virtual mooring, along-shore transects, across-shore transects, and flying a zig-zag pattern across the path of wavefronts. In the work presented here, data were collected in Lake Tahoe (USA), where local bathymetry (down to a maximum depth of 501 m) is known to produce trapped internal waves across a wide range of depths. At various locations, internal waves were concurrently measured using a G2 Slocum glider, moored thermistors and a moored Acoustic Doppler Current Profiler (ADCP). Using these complementary datasets, we can compare the effectiveness of existing and new sampling approaches by flying multiple missions where the vehicle's path varies in orientation and length relative to the wavelength and return period of known internal waves. Internal waves can be identified using spectral analysis of temperature time-series measurements, producing a power spectrum similar to the Garrett-Munk spectrum. Peaks in the power spectrum are expected at known (from previous observational and modelling work) and calculated frequencies corresponding to specific internal wave modes. The success of the sampling method can be assessed by the extent to which the expected spectral peaks are evident in the power spectrum. Additionally, through the application of a dynamic flight model, the vertical water velocities experienced by the glider can be estimated and compared to those expected from internal waves and measured by a nearby moored ADCP. Other criteria to be considered are the width of the confidence interval, the possibility of double counting waves in closed basins, and minimization of spatio-temporal smearing. Identifying the best way to employ a glider to measure an internal wave will lead to improved data collectio","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"52 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":"126806157","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":"A Novel Double Layered Weighted Potential Field Framework for Multi-USV Navigation towards Dynamic Obstacle Avoidance in a Constrained Maritime Environment","authors":"Tamzidul Mina, Yogang Singh, B. Min","doi":"10.23919/OCEANS40490.2019.8962675","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962675","url":null,"abstract":"Motion planning of multiple unmanned surface vehicles (USVs) towards increased autonomy and wider coverage of the maritime environment is a pertinent requirement. Given the numerous types of USVs currently available with a wide spectrum of maneuvering capabilities, we present a generalized multi-USV navigation framework adaptable to specific USV maneuvering response capabilities for dynamic obstacle avoidance. The present paper integrates an optimal path planning with safety distance constrained A* algorithm and a proposed adaptively weighted potential field based path following approach with collision avoidance based on USV maneuvering response times. The system allows USVs with fast maneuvering abilities to react late and slow USVs to react sooner to oncoming moving obstacles gradually such that a smooth path is followed by the USV group with reduced cross track error. Simulation results validate reduced cross track error for slow and fast maneuvering response time multi-USV teams.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"15 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":"127006800","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":"The Ocean Best Practices System - Supporting a Transparent and Accessible Ocean","authors":"P. Buttigieg, S. Caltagirone, P. Simpson, J. Pearlman","doi":"10.23919/OCEANS40490.2019.8962680","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962680","url":null,"abstract":"The development and deployment of best practices are playing increasingly important roles in supporting ocean observing. By their nature, well-adopted and reviewed best practices facilitate interoperability, reproducibility and enhance the quality of data and information products. To be effective, best practices must be easy to discover, access and adopt. Unfortunately, a wealth of best practices is undigitized, buried in local repositories or scattered on the web. To reduce this fragmentation and to help meet the urgent and existential global challenges rapidly approaching (see, for example, UN Decade of Ocean Science for Sustainable Development), the IOC-UNESCO Ocean Best Practices System (OBPS) has been created. The OBPS was recently described from an ocean research perspective [1]. In this paper, we describe the system's underlying technology and its core mission to enable content discovery and management through fine-scale indexing via text-mining and ontology-based semantic search tools. This relies on the reuse of well-adopted community thesauri and ontologies linking knowledge across the marine domain, through to the Sustainable Development Goals. We have implemented a constellation of software modules around the core OBPS repository (OBPS-R) to create a new, powerful, and extensible resource to accelerate best practice co-development, discovery, and access through intuitive user interfaces. While the system is operational, there are still many areas where further development can enhance the support of ocean observing. We address these in this paper and we invite the broader community to contribute to our common mission's open source codebase as well as creating and contributing ocean best practices to the OBPS.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"39 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":"129075767","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":"Convolutional-Neural-Network-based Underwater Object Detection Using Sonar Image Simulator with Randomized Degradation","authors":"Minsung Sung, Meungsuk Lee, Jason Kim, Seokyong Song, Young-woon Song, Son-cheol Yu","doi":"10.23919/OCEANS40490.2019.8962403","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962403","url":null,"abstract":"This paper proposes a method to detect underwater objects using sonar image simulator and convolutional neural network (CNN). Instead of simulating very realistic sonar images which is computationally complex, we implemented a simple sonar simulator that calculates only semantic information. Then, we generated training images of target objects by adding randomized degradation effects to the simulated images. The CNN trained with these generated images is robust to the degradation effects inherent in sonar images and thus can detect target objects in real sonar images. We verified the proposed method using the sonar images captured at sea through field experiments. The proposed method can implement object detection more easily because it only uses simulated images instead of real sonar images which are challenging to acquire. The proposed method can also be applied to other sonar-image-based algorithms.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"54 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":"123827849","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":"Electronically Controlled Deep Sea Sampling Tube Pressure Maintaining Cutting Device Capable of Long-term Use","authors":"Hai Zhu, Jia-wang Chen, Yuan Lin, Peihao Zhang, Z. Ren, Xiaoling Le, Jing Xiao, Ziang Feng","doi":"10.23919/OCEANS40490.2019.8962564","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962564","url":null,"abstract":"A kind of sample tube pressure-keeping cutting device is designed, which is feasible from the perspective of manufacturing and assembly, and the relevant Ansys simulation is carried out to verify the rationality of the structure. The biggest breakthrough is that one installation can realize multiple cutting of sampling pipes, eliminating the step of cleaning sea mud in the pipes. In addition, the redesign of the cutting knife and the re-selection of the outer cylinder material reduced the overall size to 71.9% and the mass to 22.3%. Anti-sludge blocking design was carried out, thus realizing long-term use design.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"8 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":"123927991","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":"Integration and Performance Study of Full Functional Sea Farm Inspection Platform for Aquaculture Application","authors":"Ottar L. Osen, Sigurd Olav Liavåg, Lars Even Sætre, Ole Morken, Houxiang Zhang","doi":"10.23919/OCEANS40490.2019.8962801","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962801","url":null,"abstract":"This paper describes the incremental development of a concept called Sea Farm Inspection Platform. The purpose of the project is twofold. Firstly, it is a very relevant and good project for students. Secondly, there are significant opportunities for such innovations in the aquaculture industry. The Sea Farm Inspection Platform consists of essentially a low-cost USV (semi-submersible design) that carries a low-cost ROV that can be used to inspect aquafarm installations. The operation principle is that the USV can be navigated to the desired location by the use of thrusters, either operated manually or through the built-in autopilot. When the desired location is reached the ROV can be deployed and lowered into the water column by using the on-board launch and recovery system which consists of a winch and a docking mechanism. The ROV has a camera and environmental sensors and has thrusters that allow it to change heading (yaw) and position in the horizontal plane (surge and sway), the vertical position (heave) is controlled by the winch. Hence, the ROV has negative buoyancy and is hanging below the USV as a pendulum. Structural integrity of fish farms is paramount. This applies to structures, nets and moorings. The installations are expensive by themself and the nets contain fish of significant value. Escaped fish can cause great financial loss to the owners and severe damage to the environment. Further, it is important to monitor the health and the ability for the fish to utilise the fodder. Aquafarms are subject to diseases from pathogens and algae blooms can kill all the fish in an installation in a very short time. Hence, thorough inspection and monitoring of the facilities is extremely important. This innovation is a step down the path towards more automation in the aquaculture industry and will hopefully inspire developments of similar products. The project is now in its 3rd year. There have been a series incremental developments as more or less new teams of students have been working on the project every semester. From a pedagogical point of view, this project has served as a good example of Project-Based Learning. In the following sections, we will describe some of the recent changes in the design and the integration process. One section will also give more background on the pedagogical aspects of the project and how well it complies with the concept of Project-Based Learning and Constructive Alignment.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"20 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":"123995025","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":"Surface Condition Surveys in Ice Covered Waters using Acoustic Reverberation","authors":"R. Hildebrand, Patrick L. Kelley, Drake B. Lafleur, Jacob M. Brendly, D. C. Baumann, Edoardo I. Sarda","doi":"10.23919/OCEANS40490.2019.8962728","DOIUrl":"https://doi.org/10.23919/OCEANS40490.2019.8962728","url":null,"abstract":"Acoustic reverberation time is investigated, by scale-model experiments, for its suitability as a readily-measured index of the physical surface conditions in ice-covered waters. As such, it is envisioned as the basis of expedient survey techniques for such potential applications as trapped oil detection or ice road condition monitoring. The scaled experiments, to establish feasibility, are conducted in a small tank with naturally grown ice cover, anechoic-lined side walls, and a hard bottom, imitating thereby a horizontally-extended underwater environment, like an ice-covered sea. An impulsive source generates sound up through low ultrasonic frequencies (to 90 kHz), wavelengths of which are suitability short relative to the tank dimensions that near-ideal diffuse-field reverberant conditions are surmised to prevail; decay time of the impulse (“reverberation time”) is extracted from a hydrophone signal. Results suggest high sensitivity of the reverberation time to ice coverage (vs. absence), and somewhat lower sensitivity, albeit still promising for survey techniques, to other such features as variations in ice thickness, or the presence of trapped oil; this is suggestive of likely feasibility of the proposed survey techniques at full scale.","PeriodicalId":208102,"journal":{"name":"OCEANS 2019 MTS/IEEE SEATTLE","volume":"25 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":"123346229","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}