OCEANS 92 Proceedings@m_Mastering the Oceans Through Technology最新文献

{"title":"Power Transformer Design For Tethered Underwater Vehicles","authors":"N. Forrester","doi":"10.1109/OCEANS.1992.607700","DOIUrl":"https://doi.org/10.1109/OCEANS.1992.607700","url":null,"abstract":"Tethered underwater vehicles benefit from the smallest possible tether through reduction of both tether handling gear and tether drag. If the vehicle is powered through the tether, a transmis- sion voltage in the range of one to three kilovolts usually results in the smallest tether. AC power transmission system can use trans- formers for conversion of the high voltage to service levels. Transformers for underwater vehicles are designed with different goals than conventional transformers. Weight is a prime consider- ation for any neutrally buoyant vehicle and thus most other con- straints, including efficiency, are relaxed in pursuit of lower weight. Design starts with a prioritized list of constraints. Non-linear optimi- zation can then apply these constraints to the basic electro-magnetic and thermal equations governing a transformer. The result is a tenta- tive core and winding design that can be compared with the original goals and iterated to achieve any necessary compronlises. An example design for a 400 Hz, three-phase, oil cooled, pressure compensated, toroidal system delivering 20 kilowatts DC to a vehicle is detailed. The design target and \"as manufactured\"' parameters are compared. I INTRODUCTION","PeriodicalId":158109,"journal":{"name":"OCEANS 92 Proceedings@m_Mastering the Oceans Through Technology","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116724394","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 Sonar Receiver And Oceanography","authors":"M. Bouvet, M. Cresp","doi":"10.1109/OCEANS.1992.612734","DOIUrl":"https://doi.org/10.1109/OCEANS.1992.612734","url":null,"abstract":"Starting from the functions of a sonar system (detection, classification and localization), this paper illustrates the links between the design of a sonar receiver and oceanography. Using specific examples, it details what the sonar designer needs from oceanography and it shows how the environment knowledge can be used and should be used in order to improve overall sonar performances.","PeriodicalId":158109,"journal":{"name":"OCEANS 92 Proceedings@m_Mastering the Oceans Through Technology","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134380222","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":"Incoherent Imaging With Ambient Noise","authors":"M. Buckingham","doi":"10.1109/OCEANS.1992.612743","DOIUrl":"https://doi.org/10.1109/OCEANS.1992.612743","url":null,"abstract":"Abst rac t Traditionally, two acoustic techniques familiarly known a s “active” and “passive” are used for probing the ocean. With an active system, a pulse of sound is transmitted and the presence of a n object inferred from the echo it produces. The passive approach involves simply l istening for the sound tha t a n object itself emits. A third method of using sound in the ocean, which is neither active nor passive, relies on ambient noise generated by breaking waves and other naturally occurr ing phenomena a t the sea sur face to “illuminate” objects in the ocean. The radiation scattered by an object is focussed to create a pictorial image of the object on a visual display monitor. This new concept has been designated “acoustic daylight” by analogy with daylight in the atmosphere: the ambient (acoustic) noise field and the (optical) daylight field both consist of incoherent radiat ion travell ing randomly in all di rect ions. Recent exper iments conducted off Scripps pier, in which a parabolic reflector was used a s an acoustic lens for focussing the scattered noise, indicate tha t objects in the ocean can indeed be detected using the acoustic daylight technique .","PeriodicalId":158109,"journal":{"name":"OCEANS 92 Proceedings@m_Mastering the Oceans Through Technology","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132828491","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":"Comparison Of Noise Models And Resolution Capabilities For Satellite Radar Altimeters","authors":"R. V. Sailor, M. Driscoll","doi":"10.1109/OCEANS.1992.612697","DOIUrl":"https://doi.org/10.1109/OCEANS.1992.612697","url":null,"abstract":"Satellite radar altimeters measure sea surface topography along the satellite subtrack using reflected radar pulses. Error sources that interfere with the recovery of instantaneous sea surface height relative to the earth’s ellipsoid include those from the environment (e.g., atmospheric propagation delays), plus the bias and random electronic noise in the altimeter instrument itself The focus of this paper is on the description and quantification of the noise due to the altimeter instrument and on the relative capabilities of different altimeter missions to resolve shortwavelength geoid features. We have applied consistent definitions and techniques to develop noise models for four different satellite altimeter missions: GEOS-3, Seasat, Gcosat, and ERS-1. As the measurement technology has advanced, altimeter noise levels have decreased, and shortwavelength resolution limits have improved. The altimeter noise models derived in this work are necessary for geodetic collocation analyses and optimal least-squares interpolation. They are also valuable for preprocessing altimeter data for oceanographic analyses, and for choosing parameters for classical filter design (e.g., high frequency limits and roll-off rates).","PeriodicalId":158109,"journal":{"name":"OCEANS 92 Proceedings@m_Mastering the Oceans Through Technology","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134529371","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":"Real-time Water Column Hydrocarbon Mapping Using The Battelle Ocean Sampling System (BOSS) To Identify Chronic And Spilled Oil Inputs To The Coastal Marine Environment","authors":"G. Douglas, W. Steinhauer","doi":"10.1109/OCEANS.1992.607715","DOIUrl":"https://doi.org/10.1109/OCEANS.1992.607715","url":null,"abstract":"Petroleum hydrocarbons enter the marine ecosystem from a variety of sources including industrial and domestic sewage discharges, surface runoff, creosote discharges from pier pilings, atmospheric deposition and oil spills. The analytical costs associated with traditional GC/FID and GC/MS hydrocarbon measurements often limit the number of samples collected and analyzed for hydrocarbon fate and transport studies resulting in a loss of spatial resolution. The ability to monitor petroleum hydrocarbons in coastal water columns using real-time detection systems provides improved spatial analytical resolution without excessive analytical costs. These tools can be used to identify chronic coastal inputs and track subsurface oil transport during an oil spill. Sampling sites for traditional water sample collection and analysis can be designated based on criteria developed wing the real-time analytical system. This approach will reduce overall analytical costs by screening out the areas with little or no hydrocarbons, and target the collection of selected water samples from contaminated areas. Discrete water samples can then be: analyzed by GCjFID and GC/MS methods and used to Calibrate the real-time hydr'ocarbon detection system. In this paper, we present the results of a study where real-time water column hydrocarbon measurements were combined with discrete laboratory analytical measurements to develop a hydrocarbon distribution map. An integrated sampling system made up of an underwater sensor unit and pumping system has been developed to provide realtime in situ salinity, temperature, and depth measurements and continuous water samples for onboard fluorometry (excitation 254nm, emission 350nm). Discrete water samples were collected and analyzed for aliphatic and total hydrocarbons by GC/FID and aromaitic hydrocarbons by GC/ MS. Low analytical detection limits (saturated hydrocarbons 0.2 pg/l, total hydrocarbons 10 pg/l, and aromatic hydrocarbon 10 ng/l) were required to monitor the hydrocarbon distributions in these samples. These measurements were used to Calibrate the real-time fluorometry measurements and develop a coastal hydrocarbon input map. The effectiveness of this analytical approach to delineate chronic and oil spill inputs to marine waters will be discussed.","PeriodicalId":158109,"journal":{"name":"OCEANS 92 Proceedings@m_Mastering the Oceans Through Technology","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133251230","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":"Automated Sea-bed Classification System For Echo-Sounders","authors":"X. Lurton, E. Pouliquen","doi":"10.1109/OCEANS.1992.612709","DOIUrl":"https://doi.org/10.1109/OCEANS.1992.612709","url":null,"abstract":"A method is proposed for real-time identification of the continental shelf sea-bottom type, using signal time envelopes from standard echo- sounders for fisheries and bathymetry. The method consists in comparing the reverberated signals with a set of references computed for a given sounder and a variety of water heights and sea bottom types. The basic method is at first presented. The experimental setup used for in-situ measurements is then described; the results of at-sea campaigns are finally presented and commented. 1. ECHO-SOUNDERS BACKSCATTERED SIGNALS","PeriodicalId":158109,"journal":{"name":"OCEANS 92 Proceedings@m_Mastering the Oceans Through Technology","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133344396","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":"Intercomparison Between Towed And Stationary Acoustic Doppler Current Profilers","authors":"C. R. Nichols, R. Williams, G. Appell","doi":"10.1109/OCEANS.1992.607666","DOIUrl":"https://doi.org/10.1109/OCEANS.1992.607666","url":null,"abstract":"This paper discusses the use of a towed acoustic Doppler current profiler (ADCP) for the purpose of evaluating in situ current meters. Data are presented from comparison tests between a towed and bottom-mounted ADCP. Velocity contours parallel and transverse to the main navigation channel under the Sunshine Skyway Bridge (SSB) in Tampa, Florida from a 600 KHz towed ADCP are compared to bottom-mounted current profiles from a 1200 KHz ADCP placed under the SSB. Data are presented to show instrument differences which are a combiination of random and systematic error. The study finds that the bottom-mounted ADCP is measuring current speeds accurately and is in the optimal location to report maximum channel currents under the SSB. The present location of the bottom-mounted ADCP under the SSB in the middle of the main navigation channel reports velocities accurate to 5 cmls. This metho+ is considered a viable technique for evaluating the reliability of moored or bottom-mounted units.","PeriodicalId":158109,"journal":{"name":"OCEANS 92 Proceedings@m_Mastering the Oceans Through Technology","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116669604","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":"An Autonomous Expendable Conductivity, Tempemture, Depth Profiler For Ocean Data Collection","authors":"J. Downing, B. DeRoos, K. McCoy","doi":"10.1109/OCEANS.1992.607663","DOIUrl":"https://doi.org/10.1109/OCEANS.1992.607663","url":null,"abstract":"An Autonomous Expendable Conductivity-Temperature-Depth Profiler (AXCTD) for profiling temperature, conductivity, pressure, and other parameters in remote oceanic regions is described. The AXCTD is a microcomputer-controlled sensor package that can be deployed by unskilled operators from ships or aircraft. It records two CTD profiles (one during descent and another during ascent) and CTD times series while on the bottom and adrift at the surface. Recorded data are transmitted to an ARGOS satellite with ground-positioning capabilities. The AXCTD can provide ``sea truth`` for remote sensing, perform environmental and military surveillance missions, and acquire time-series and synoptic data for computer models.","PeriodicalId":158109,"journal":{"name":"OCEANS 92 Proceedings@m_Mastering the Oceans Through Technology","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129553169","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 Wave Induced Skew Errors In Acoustic Doppler Current Profiler Measurements From High Shear Regimes","authors":"P. Pullen, M. Mcphaden, H. Freitag, J. Gast","doi":"10.1109/OCEANS.1992.607669","DOIUrl":"https://doi.org/10.1109/OCEANS.1992.607669","url":null,"abstract":"Abstruct-Downward-looking RD Instruments acoustic Doppler current profilers (ADCPs) are presently mounted on surface moorings along the Pacific equator as part of the Tropical Ocean-Global Atmosphere Program. In the equatorial region, the South Equatorial Current/Equatorial Undercurrent system creates high vertical shear in the zonal velocity. ADCP skew error is known to occur in high vertical shear regimes due to the misposition of the ADCP tracking filter with respect to the frequency of backscattered sound energy. Skew errors in the moored ADCP current measurements from the eastern equatorial Pacific are particularly troublesome in the first bin below the surface. The filter position for the first bin is set by the values measured from previous pings according to the E-command setup. Calculations of the expected skew error from typical mean zonal shears in the equatorial region were made prior to deployment of the moored array using equations provided by RD Instruments. However, the skews calculated from the mean curve only account for about 1/3 of the velocity errors observed in a moored ADCP system at O\", llOoW in spring 1991. This underestimate of error is due to the fact that the skew must be computed on a ping-to-ping basis, incorporating the vertical and horizontal velocity changes that occur each ping. A model for surface wave induced skew error i s presented which includes ping-to-ping velocity changes in the skew calculation. In high shear regimes, such as the equatorial region, the model calculates skew errors of equal magnitude to those observed in the data. Alternative ADCP setup commands, tested with shipboard data, are presented to minimize tracking filter skew errors in future measurements.","PeriodicalId":158109,"journal":{"name":"OCEANS 92 Proceedings@m_Mastering the Oceans Through Technology","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129665258","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 Linear Predictive Identification Of Yaw Stretch Areas In Side Scan Sonar Imagery","authors":"R.S. Pascucci, M. Deaett, P. Rattey","doi":"10.1109/OCEANS.1992.612723","DOIUrl":"https://doi.org/10.1109/OCEANS.1992.612723","url":null,"abstract":"In this paper we apply 2-dimensional linear predictive texture analysis to the identification of yaw stretched areas of side scan sonar imagery. The image is first divided into blocks, the dimension of which is determined by the correlation distance of the 2-D autocorrelation function. For each block of the training image, an LPC analysis is conducted and, by vector quantization, three types ofcodebook textures are established. ' b o code words are associated with yaw stretch areas and a third is related to the normal background. Each block of the scanning imagery is mapped via least distortion into either a background or a yaw stretch codeword. The yaw stretch blocks are then analyzed for horizontal patterns of texture which are indicative of yaw stretch areas. These areas are then tagged and passed to an image recognition processor so that suitable adjustments to the detection algorithm can be made. Fig. 1. The 2-D Causal Mask Used in Linear Predictive Texture Analysis","PeriodicalId":158109,"journal":{"name":"OCEANS 92 Proceedings@m_Mastering the Oceans Through Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129800857","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}