OCEANS 2007最新文献

{"title":"High Brightness Light Emitting Diodes for Ocean Applications","authors":"K. Hardy, M. Olsson, J. Sanderson, K. Steeves, B.P. Lakin, J.E. Simmons, P. Weber","doi":"10.1109/OCEANS.2007.4449401","DOIUrl":"https://doi.org/10.1109/OCEANS.2007.4449401","url":null,"abstract":"Light Emitting Diodes (LEDs) are emerging in the undersea world as a reliable, efficient light source capable of narrow or wide chromatic bandwidth. Use of gas discharge lamps as light sources in the deep sea is complicated by the need to pressure protect the sealed bulbs. LEDs provide a viable alternative for many diver, submersible, and unmanned vehicle applications. While they are proving versatile, they also have unique characteristics that require designers to think differently. This paper will highlight those differences, draw similarities, offer common language, and suggest future developments. At sea tests with Woods Hole Oceanographic Institution's DSV ALVIN will be described. DeepSea Power & Light (DSPL) has been involved in severe environment LED lighting for over 10 years in a line of Pipe Inspection Video Cameras and has been involved in advanced underwater lighting since the company's inception 25 years ago. DSPL has successfully tested LED arrays to pressures in excess of that found in the deepest ocean trenches.","PeriodicalId":214543,"journal":{"name":"OCEANS 2007","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124005476","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":"Selection of Marine Protected Areas for conserving estuaries using surrogate approach","authors":"William Gladstone","doi":"10.1109/OCEANS.2007.4449397","DOIUrl":"https://doi.org/10.1109/OCEANS.2007.4449397","url":null,"abstract":"Establishing marine protected areas in estuaries has been advocated as the efficient route in conserving the sensitive estuarine environment. However, selecting priority areas for conservation of estuarine biodiversity require detailed biodiversity inventories that are difficult to access. A potential solution is the use of surrogates that are readily measured and reflect the total biodiversity. Indicator groups and higher taxa are widely suggested as potential surrogates in establishing conservation areas. The performance of indicator groups and higher taxa as surrogates were assessed in one estuary in south-east Australia by traditional approach \"correspondence in species richness\" and using complementarity-based approaches \"correspondence in compositional dissimilarity and coincidental representation of target species in simulated MPA for surrogates\". Of 16 taxa examined, annelids, arthropods and molluscs were identified as reliable surrogates in representing biodiversity of target species. This study showed that genus-level data of indicator taxa could efficiently identify priority areas for target species. Family-level data of indicator taxa may be used as surrogate with caution. Given wide differences among aquatic habitats, there is a special need for finding indicator groups for different habitats.","PeriodicalId":214543,"journal":{"name":"OCEANS 2007","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124261647","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":"ESONET: a network to integrate European research on sea","authors":"R. Person, L. Beranzoli, C. Berndt, J. J. Danobitia, M. Diepenbroecke, P. Favali, M. Gillooly, V. Lykousis, J. M. Miranda, S. Pouliquen, I. Priede, R. Santos, L. Thomsen, T. C. Weering, Chang Chung Sing Waldman","doi":"10.1109/OCEANS.2007.4449294","DOIUrl":"https://doi.org/10.1109/OCEANS.2007.4449294","url":null,"abstract":"ESONET is an European network of excellence (NoE) associating 50 partners (research centres, universities, industrials and SMEs) from 14 countries: France, Germany, Italy, UK, Spain, Portugal, Greece, Belgium, Ireland, the Netherlands, Norway, Sweden, Bulgaria and Turkey. More than 300 scientists and engineers will participate to its activities. The goal of the ESONET NOE is the lasting integration of European research on deep sea multidisciplinary observatories. Over the initial 4 years, the approach will be to merge the programmes of members organisations through research activities addressing the scientific objectives and networking activities specially designed for integration and spreading excellence.","PeriodicalId":214543,"journal":{"name":"OCEANS 2007","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125321273","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 Fault-Tolerant Fuzzy-Logic Based Redundancy Resolution Method for Underwater Mobile Manipulators","authors":"S. Soylu, B. Buckham, R. Podhorodeski","doi":"10.1109/OCEANS.2007.4449387","DOIUrl":"https://doi.org/10.1109/OCEANS.2007.4449387","url":null,"abstract":"In this work, a fault-tolerant redundancy resolution scheme is presented that allows a single 6-DOF command to be distributed over a small URVM system composed of an otherwise underactuated URV and serial manipulator. The URVM system admits an infinite number of joint-space solutions for each commanded end-effector state due to its inherent redundancy. The primary objective is realized using the right Moore-Penrose pseudoinverse solution. The secondary objectives are: avoiding manipulator joint limits, avoiding singularity and high joint velocity; keeping the end-effector in sight of the on-board camera minimizing the URV motion; and minimizing the drag-force resistance, or weathervaning. Each criterion is defined within the framework of the Gradient Projection Method. The hierarchy for the secondary tasks is established by a low-level artificial pilot that determines a weighting factor for each criterion based on if- then type fuzzy rules that reflect an expert human pilot's knowledge. A Mamdani fuzzy inference system is used to interpret the fuzzy rules based on the sensory knowledge. The resulting weight schedule yields a self-motion (null-space motion) that emulates how a skilled operator would utilize the full capabilities of the URVM to achieve the secondary objectives. The proposed redundancy resolution scheme has a fault-tolerant property. When a joint failure occurs, the scheme automatically redistributes the end-effector velocity command taking into account the faulty joints. To demonstrate the efficacy of the proposed scheme, several numerical simulations are performed The results illustrate the validity of the proposed redundancy scheme.","PeriodicalId":214543,"journal":{"name":"OCEANS 2007","volume":"17 7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126128066","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":"Mapping of Submerged Aquatic Vegetation Using Autonomous Underwater Vehicles in Nearshore Regions","authors":"M. Jones, L. Miller, D. Woodruff, D. Ewert","doi":"10.1109/OCEANS.2007.4449331","DOIUrl":"https://doi.org/10.1109/OCEANS.2007.4449331","url":null,"abstract":"The use of an autonomous underwater vehicle (AUV) equipped with sidescan sonar was investigated for determining the boundaries of nearshore submerged aquatic vegetation beds, specifically eelgrass (Zostera marina). Shifts in eelgrass bed morphology, size, and distribution are used as indicators in monitoring programs to measure the impacts of coastal development and environmental stressors on nearshore ecosystem health and to establish the efficacy of restoration programs. However, many monitoring programs necessarily extend over multiple-year time periods. Therefore, techniques that are easily reproducible, accurate, and cost-effective can demonstrate distinct advantages over some of the more traditional and labor-intensive methods, such as diver assessments and transects of shoot counts. Remote monitoring of eelgrass beds using satellite and aerial imagery has been demonstrated with moderate success, but requires groundtruthing, which can be costly and which frequently cannot delineate the deeper boundaries of eelgrass beds. One possible means for low-cost mapping is the use of AUVs equipped with acoustic imaging hardware. AUVs provide an ideal platform, because they can be deployed by small teams (two people), they are highly maneuverable, they can cover large areas over a relatively short time period (3 knot operational speed), and they are equipped with multiple oceanographic instruments for correlated data collection. This paper describes the use of sidescan-equipped AUV technology deployed over multiple time periods at the same location where imagery of eelgrass beds was obtained and analyzed for comparative purposes.","PeriodicalId":214543,"journal":{"name":"OCEANS 2007","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129878933","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 Studies Institute's Ocean Observatory Program: CICORE in San Pedro Bay, California","authors":"R. Pieper, S. Kelly","doi":"10.1109/OCEANS.2007.4449381","DOIUrl":"https://doi.org/10.1109/OCEANS.2007.4449381","url":null,"abstract":"The Oceans Studies Institute (OSI) of the California State Universities (CSU) has three multi-sensor instrumentation sites in the Southern California Bight as part of the CSU's Center for Integrative Coastal Observation, Research and Education (CICORE) program. The program, under the auspices of NOAA-COTS, has a mandate to monitor California coastal water and shores. OSI was added to the CICORE program in 2004. The program is under the direction of Dr. Richard Pieper, director of the Southern California Marine Institute (SCMI). SCMI provides vessel, logistical and scientific support to eight CSU campuses, the University of Southern California and Occidental College. Technical support to the CICORE program is provided by the College of Engineering, California State Polytechnic University, Pomona. The OSI/SCMI CICORE program is unique in that data from the sites are transmitted by UHF spread-spectrum telemetry to the OSI/SCMI facility located at Fish Harbor, Terminal Island. It is transferred to the internet for near real time global access. Each site monitors temperature, chlorophyll-a fluorescence, turbidity, pH, conductivity/salinity, dissolved oxygen, solar panel voltage and battery voltage. This paper presents an overview of the system, with emphasis on the advantage of high data rate monitoring and the use of the data in successful prosecution of marine polluters.","PeriodicalId":214543,"journal":{"name":"OCEANS 2007","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130137345","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":"Performance Analysis of Multichannel Lattice Equalization in Coherent Underwater Communications","authors":"J. Gomes, António Silva, S. Jesus","doi":"10.1109/OCEANS.2007.4449374","DOIUrl":"https://doi.org/10.1109/OCEANS.2007.4449374","url":null,"abstract":"This work examines the numerical fixed-point performance of a new multichannel lattice RLS filtering algorithm using data from two underwater acoustic communication experiments. The algorithm may be an appealing choice for underwater equalization due to its robust numerical behavior and linear scaling of the computational complexity with filter order. Simple modifications to widely-used methods for carrier/timing synchronization and symbol slicing in transversal equalizers are proposed. Experimental results show that the algorithm is as accurate as the similarly array-based QR-RLS, tolerating word lengths as low as 16-20 bits with minor degradation relative to floating-point benchmarks. These features, coupled with a very modular and regular structure, are highly desirable in energy- efficient hardware or embedded implementations.","PeriodicalId":214543,"journal":{"name":"OCEANS 2007","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129560144","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 of a Modular, Compact, Multi-Role Remotely Operated Vehicle for Sheltered Water Operations","authors":"P. Sinha, K. Stiehl, E. Huo, O. Oyebode, R. Dokov, S. Chin, R. Price, R. Larson","doi":"10.1109/OCEANS.2007.4449392","DOIUrl":"https://doi.org/10.1109/OCEANS.2007.4449392","url":null,"abstract":"Since its founding in 2003, the MIT ROV Team has been participating in the Marine Advanced Technology Education (MATE) Center's International ROV Competition. This year's challenges, in recognition of the International Polar Year, include operations in environments made to resemble those found in the Polar Regions. This includes working in currents, under ice sheets and in simulated open ocean environments. The three missions, each approximately 15 minutes long and in depths of up to 20 feet, include recovery and deployment of science packages and related support structures, the collection of faunal samples and repair and maintenance work at stations under water. In keeping with its vision to look beyond the competition and push the envelope, the MIT ROV Team built on the lessons learnt during the design, construction and operation of its fourth generation ROV, MTHR, to design MIT ROV 5.0, a compact, powerful, highly maneuverable and modular robot capable of not only participating in the competition, but also performing a variety of tasks in the open environment. MIT ROV 5.0 was primarily designed to be an exploration robot meant to operate in sheltered waters, that is, with currents below one knot, lack of powerful localized turbulent flow and the absence of highly corrosive materials. The major design requirements included ease of operation, including setup, maintenance, dives and recovery, modularity, to allow quick reconfiguration to suit a variety of missions, robustness, so that it would stand up to the rigors of the open environment, small size, for greater maneuverability and low cost, for ease of reproduction. We came up with a robot that was slightly bigger than MTHR with two modular payload bays with standard connectors that could accommodate mission-specific packages. The control box contains custom designed PC-104 size circuit boards that can support a number of different actuators and thrusters and adequate space for NiMH or LiON battery packs, which can both be used. Each board can be switched easily due to extensive use of standard sizes and connection interfaces. The frame uses high strength ABS plastic side plates with LEXAN cross-struts. The tether is a single strand Kevlar-jacketed fiber-optic cable with a Kevlar support string for added security. This tether can be replaced by a regular Ethernet or CAT-V cable is the need arises. Thus the vehicle is truly modular in every way. The MIT ROV 5.0 system as designed is very easy to use. The control software can be run off virtually any computer, using the keyboard or a standard USB joystick. The vehicle itself connects to the computer using a USB-serial interface. The entire system can be setup and ready to go in under five minutes. An on-board guidance system consisting of an inertial navigation unit and a magnetic compass provide heading, attitude and position data, as well as performing station-keeping functions, allowing effective operation in currents and low-visibility condi","PeriodicalId":214543,"journal":{"name":"OCEANS 2007","volume":"125 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131283778","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":"K omega beamforming implementation on IBM cell processor","authors":"S. Moinuddin","doi":"10.1109/OCEANS.2007.4449307","DOIUrl":"https://doi.org/10.1109/OCEANS.2007.4449307","url":null,"abstract":"The frequency domain beam forming techniques specially using 2D-FFT process are used mostly in passive sonar. It provides good results mostly in applications like towed arrays that are towed behind submarines and ships. The linear hydrophone array is sampled in time .The data is transformed from time domain into frequency domain by FFT process. Then another FFT is applied along the nth frequency bin in space. This provides good frequency contents of the towed arrays. The plot obtained from this 2D-FFT process is called k-omega plot. In which frequency is on x axis and wave number k on y axis. K-omega beam forming is widely used in passive sonar for detection, classification and localization purposes. The technique requires uniform linear array for beam forming. The linear hydrophone arrays are split into further sub arrays. These sub arrays are spaced spatially according to different cut frequencies. With the introduction of long passive arrays for naval and oil exploration purposes, the parallel K-omega processing problems becomes complex. Traditionally the implementation is done on cluster of IBM PowerPCs or more recently Intel Xeon clusters. The heavy computation load is often compromised with more optimized algorithms fit to specific architecture. This in practice requires major overhaul in the system if new feature is to be incorporated in the passive towed array sonar system. In this research paper the K-omega beam forming is implemented on IBM cell processor. The cell processor with its inherent parallelism in architecture provides an opportunity to execute processing of sub arrays concurrently. The K-omega beam forming is implemented on simulated 5 to 7 nested sub arrays and results are computed in simulator and tested against the Matlab outputs. The k omega beam forming used in this implementation depends on FFTW library along with IBM math, vector and matrix libraries. The implementation is benchmarked using IBM cell processor simulator. Another aspect of cell processor found in this research paper is its very fine memory handling capability. This is vital for Matrix calculations and iterative tasks. From the implementation it is evident that this can be easily ported to commercially available system i.e. Sony playstation 3. The Sony playstation 3 with Linux fedora core 6 is ideal for such an application and it can be used for training of passive sonar operator.","PeriodicalId":214543,"journal":{"name":"OCEANS 2007","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131363884","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 New Vector Sensor Receiver for Underwater Acoustic Communication","authors":"Ali Abdi, Huaihai Guo, P. Sutthiwan","doi":"10.1109/OCEANS.2007.4449191","DOIUrl":"https://doi.org/10.1109/OCEANS.2007.4449191","url":null,"abstract":"In this paper we have shown that by taking advantage of the acoustic particle velocity, in addition to the acoustic pressure, multichannel reception can be accomplished in underwater channels. Theoretical formulation and Monte Carlo simulations are provided for a vector sensor equalizer that measures the pressure and the velocity at a single point in space. These results demonstrate the usefulness of a compact vector sensor as a multichannel equalizer.","PeriodicalId":214543,"journal":{"name":"OCEANS 2007","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127668680","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}