OCEANS 2009最新文献

{"title":"Statistical space-time-frequency characterization of MIMO shallow water acoustic channels","authors":"A. Zajić","doi":"10.23919/OCEANS.2009.5422278","DOIUrl":"https://doi.org/10.23919/OCEANS.2009.5422278","url":null,"abstract":"This paper proposes a geometry-based statistical model for multiple-input multiple-output shallow water acoustic multipath fading channels. From the reference model, the corresponding space-time-frequency correlation function is derived. Finally, the derived spatial and temporal correlations are compared with the empirically obtained channel statistics and close agreement is observed.","PeriodicalId":119977,"journal":{"name":"OCEANS 2009","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134322841","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":"Promoting interoperable ocean sensors the Smart Ocean Sensors Consortium","authors":"N. Cater, P. Eng., T. O'Reilly","doi":"10.23919/OCEANS.2009.5422448","DOIUrl":"https://doi.org/10.23919/OCEANS.2009.5422448","url":null,"abstract":"As we continue to expand our activities on and beneath the surface of our oceans, there is an ever-expanding requirement to monitor and collect océanographie and meteorological data in increasingly remote and harsh marine environments. Ocean Observing systems provide critical information; information in support of problem solving, decision making, prediction and forecasting as well as in support of offshore engineering and design activities. In short, these systems enable us to better understand the oceans around us. Ocean data are often expensive and logistically challenging to collect. It is crucial that maximum value is derived from the investment made in ocean observation. Collecting and delivering data in a cost effective and timely manner is essential to its viability and ultimately its value to the end user. Over the last two decades there has been an explosion in the use of GIS (Geographic Information Systems) in ocean observation across a wide range of sectors from aquaculture to defense and security. As acceptance and usage of GIS continues to grow in these disparate sectors, many applications have developed their own data standards and their own proprietary software for processing, analysis and presentation. The concept of Open GIS was conceived with the vision of creating a set of open interface standards to enable diverse geo-processing systems to share data and communicate directly and efficiently. The Open Geospatial Consortium (OGC) was formed to develop these open interface specifications as well as to lead the education and outreach components of the initiative. In broadest terms, an ocean observing system is comprised of three primary functional layers. The \"top\" layer, from the point of view of the end user, is the application layer, the software tools that enable the user to process, interpret and act upon data. The second layer is the service layer, the hardware and software necessary to move, store and manage data. The third layer is the data collection layer consisting of the sensors and systems that are the physical interface with the ocean environment. The OGC promotes the concept of Sensor Web Enablement. A Sensor Web is a World Wide Web accessible network comprised of geographically distributed sensors and archived data. The sensors may monitor any physical parameter depending on the location and the application. The data, whether directly from sensors or from archived sources, can be located and accessed using standard communications protocols and programming tools. Fully implemented, OGC specifications will ultimately enable access to geospatial data regardless of source or location. It will enable data from different sources to be integrated and analyzed and will promote \"common look and feel\" visualization and display of information. There is considerable interest in the marine user community to define a new class of standards-based ocean sensors. These sensors can be located and identified over the World Wide Web,","PeriodicalId":119977,"journal":{"name":"OCEANS 2009","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131600893","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":"Sampling synchronization with Gigabit Ethernet","authors":"M. Henderson, T. Shaver","doi":"10.23919/OCEANS.2009.5422060","DOIUrl":"https://doi.org/10.23919/OCEANS.2009.5422060","url":null,"abstract":"In the recent past we have seen open standards based data acquisition and telemetry systems supplant proprietary systems. Asynchronous Transfer Mode (ATM) was a great choice for sonar and related synchronous sampling systems as the network was built on the concept of a synchronous backbone from which system timing could be derived. Unfortunately for all but the largest of backbones, ATM has been replaced with other open protocols, chiefly Ethernet, which lacks the underlying precept of the synchronous backbone. We have seen open standards develop in the last several years with the intent of addressing the need for synchronicity, such as IEEE 1588 and Synchronous Ethernet. QNA-TSG has developed a method of using standard Gigabit Ethernet to achieve synchronous sampling using COTS networking equipment and minor modifications that allow GPS locked, synchronous sampling. With this new extension of locking sampling to GPS timing, the technology exists now to create long baseline arrays never before realizable. Synchronization is conceptually trivial, have two things happen at the same time, which in practice is quite difficult to implement. Synchronization, at its root, requires two things: that all nodes in the system count time in the same manner, and that one moment in time can be uniquely identified as time zero. Said another way, all nodes in the system must use the same clock, and all nodes need a synchronization event. Fiber optic based Gigabit Ethernet uses a synchronous link layer that allows the physical layer to continuously recover the transport clock. Many Gigabit Ethernet COTS switches use a single clock source to drive all output data link clocks. The result is an architecture that allows all devices plugged into the same switch to have access to a common clock. For more complicated architectures that use cascaded switches it is necessary to have a switch that can carry the clock forward. This requires that the switch recover the data clock, clean the clock up, and then use that clock as the transmit clock for another port. Although no Tier 1 supplier currently offers such an option, QNA-TSG has built, demonstrated, and deployed such a device. The second step in synchronous sampling is the time zero event. An obvious standards based approach to developing a time zero event is to use NTP or one of the extensions to NTP. Unfortunately, the standards based approaches are limited in their accuracy depending on the implementation. Most implementations are limited by the interrupt latency and the distribution of that latency. Typically NTP can achieve synchronization on a typical computer of approximately 1–0.1ms, using nothing but network communications. Systems can be constructed that use GPS timing devices that feed into the computer a one pulse per second (1PPS) to improve timing accuracy to on the order of 1–10us. QNA-TSG developed a technique where the time stamping for NTP is performed at the hardware layer. Combined with an understand","PeriodicalId":119977,"journal":{"name":"OCEANS 2009","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131838978","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":"Technical metrics for acoustic evaluation","authors":"J. Fabre","doi":"10.23919/OCEANS.2009.5422313","DOIUrl":"https://doi.org/10.23919/OCEANS.2009.5422313","url":null,"abstract":"A Technical Metrics Workshop was held at NRL Stennis Space Center, MS, by the NRL Acoustics Division April 29 — May 1, 2008. The primary goal of the workshop was to identify the state-of-the-art technical and scientific metrics for the acoustic and oceanographic research and development communities. A second goal was to relate scientific metrics to engineering and performance metrics, and outline the inclusion of uncertainties in various parameters using metric variability. Participation in the workshop was significant. State-of-the-art technical applications, as well as brief insights into future metrics, requirements for metrics, standards or reference level metrics were presented. This paper briefly summarizes and presents the conclusions of the workshop. This work is a useful reference for building consistent technical metrics within the ocean and acoustic research and development community, as well as providing common guidance for measuring exit and milestone criteria, and for quantifying the contributions of interdisciplinary projects.","PeriodicalId":119977,"journal":{"name":"OCEANS 2009","volume":"158 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133107712","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":"Electric detection of divers in harbor environments","authors":"R. Lennartsson, E. Dalberg, T. Fristedt, E. Nolander, L. Persson","doi":"10.23919/OCEANS.2009.5422404","DOIUrl":"https://doi.org/10.23919/OCEANS.2009.5422404","url":null,"abstract":"In this paper we compare the detection performance of underwater electric-field sensors against divers using three different detection algorithms (matched filter, non-coherent and quadrature detectors). The detection performance is quantified and presented as ROC-curves. The empirical results are based on measurements of signatures from divers with open circuit breathing systems. They were performed during two sea-trials in diverse environments. One site is a remote area with relatively low anthropogenic activity and the other site is a busy container terminal in the port of Gothenburg, both sites in Sweden. Of the three detectors evaluated, no single detector stands out. This may imply the usefulness of fusion as a means of improving the performance in the future. In Gothenburg harbor detection of divers can be performed at signal-to-noise ratios from −20 to 0 dB, depending on the noise situation. In addition to detection, it is found that it is possible to classify a contact as a diver.","PeriodicalId":119977,"journal":{"name":"OCEANS 2009","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123185194","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":"New life for old fields: Alternatives to abandonment","authors":"P. Marshall, Y. Choo","doi":"10.23919/OCEANS.2009.5422112","DOIUrl":"https://doi.org/10.23919/OCEANS.2009.5422112","url":null,"abstract":"Advanced methods of well completion (e.g. horizontal drilling) and secondary recovery have the potential to extend our hydrocarbon resource base until alternatives can be brought onstream in the required quantities. Structural Integrity Management (SIM), also know as Platform Reassessment and Rehabilitation, is a key to extending the useful life of offshore platforms which support these activities. This paper will review recent and proposed research in the area at the National University of Singapore, as well as reassessments done to support the case for renewed drilling offshore California. The same technology is also useful for catastrophic risk modeling on a regional level.","PeriodicalId":119977,"journal":{"name":"OCEANS 2009","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128911691","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":"Buoy vandalism experienced by NOAA National Data Buoy Center","authors":"C. Teng, Stephen Cucullu, S. McArthur, C. Kohler, B. Burnett, L. Bernard","doi":"10.23919/OCEANS.2009.5422389","DOIUrl":"https://doi.org/10.23919/OCEANS.2009.5422389","url":null,"abstract":"Data buoy vandalism, which is an unlawful and willful interference with moored data buoys, has been a troublesome problem for the U.S. National Oceanic and Atmospheric (NOAA)/National Data Buoy Center (NDBC) and other buoy operators around the world. NDBC has three buoy networks -Weather and Ocean Platform (WxOP) program, Tropical Atmosphere/Ocean (TAO) buoy program, and the Tsunameter buoy program. In addition to the significant financial impact to NDBC's buoy programs and operations, vandalism disrupts the vital data collected and reported by moored buoys, which place lives, property, and economies in peril. Vandalism is not unique to just NDBC's buoy systems but is a national and international issue affecting both research and operational systems. This paper presents various vandalism incidents experienced by NDBC's three buoy networks. Prevention of buoy vandalism, including buoy and mooring system modifications, education and outreach, statutory penalty and enforcement, interagency efforts, and international cooperation and efforts, are also discussed.","PeriodicalId":119977,"journal":{"name":"OCEANS 2009","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131312699","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 ontology driven approach to increase METOC effectiveness","authors":"C. Davis, Z. Rouse, Brian Priest","doi":"10.23919/oceans.2009.5422229","DOIUrl":"https://doi.org/10.23919/oceans.2009.5422229","url":null,"abstract":"Meteorological and Oceanographic (METOC) systems that support the needs of the warfighter often involve configuring support for querying dispersed METOC data. The Joint METOC Broker Language (JMBL) has been established as the interface to query METOC data sources for machine to machine communication. To cover a wide spectrum of data needs, the JMBL standard has grown in complexity. This complexity leads to very few end users understanding the necessary elements to access many of the data types supported by JMBL. A solution commonly used requires developing graphical user interfaces (GUI) for a specific family of data requests. As the end user's needs evolve to include new data types, the GUI must be redeveloped to include the ability to access this new information. This inefficient cycle confines the capacity and flexibility of those who support the warfighter, and presents a bottleneck that devalues the data itself.","PeriodicalId":119977,"journal":{"name":"OCEANS 2009","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115334248","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":"Hyperspectral survey planning for coastal surveys","authors":"H. Ripley","doi":"10.23919/OCEANS.2009.5422230","DOIUrl":"https://doi.org/10.23919/OCEANS.2009.5422230","url":null,"abstract":"There is increasing use in today's coastal science community of airborne hyperspectral surveys. A growing knowledge base exists of what hyperspectral surveys can provide. However there is also a notable lack of understanding of what issues must be dealt with to plan and successfully complete a coastal hyperspectral survey. This paper will focus on how to effectively plan a coastal hyperspectral survey and will cover a background to the technology as well as physical factors that will affect a survey. How to minimize these impacts and how to deal with them when and if they occur will be covered. Examples will be drawn from actual project work and will be used in the presentation.","PeriodicalId":119977,"journal":{"name":"OCEANS 2009","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115360709","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 automated event detection and classification system for abyssal time-series images of Station M, NE Pacific","authors":"D. Cline, D. Edgington, K. Smith, Michael F. Vardaro, L. Kuhnz, J. A. Ellena","doi":"10.23919/OCEANS.2009.5422292","DOIUrl":"https://doi.org/10.23919/OCEANS.2009.5422292","url":null,"abstract":"The time-study data collected at the Station M site off the coast of central California includes high quality still-frame images taken in 1-hour time-lapse increments. The approximately 67,000 time-lapse images collected would take an unfeasible amount of time to fully analyze manually, and therefore would benefit from automated analysis. Towards this end, this work is an aid in the significant effort to analyze megafaunal activity and sedimentation events using an adapted version of the Automated Video Event Detection and Classification System (AVEDac) formerly designed by MBARI to analyze video collected from MBARI's remotely operated underwater vehicles (ROVs) video. This paper describes, in general, the automated system that will aid in the abundance and distribution studies of animals at the Station M site.","PeriodicalId":119977,"journal":{"name":"OCEANS 2009","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115464808","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}