Pub Date : 2014-09-01DOI: 10.1109/OCEANS.2014.7003292
Peter K. LeHardy, C. Moore
On 21 March 2014, Phoenix International Holdings, Inc. (Phoenix) was tasked by the U.S. Navy, through a multi-year Naval Sea Systems Command (NAVSEA) contract, to provide undersea search services in response to the disappearance of Malaysia Airlines Flight 370 (MH370). In support of this tasking, Phoenix deployed 9 personnel, the Navy's Towed Pinger Locator (TPL), and Phoenix's Bluefin 21 Autonomous Underwater Vehicle (AUV) - a system called Artemis - to Perth, Australia. The initial phase of the search operation took place from 04-14 April and involved using the TPL to listen for the saltwater activated Underwater Locator Beacon (ULB) “pingers” mounted to the plane's Flight Data Recorder and Cockpit Voice Recorder (the black boxes). Working aboard the Australian Defense Vessel (ADV) Ocean Shield roughly 1600 km North West of Perth, Phoenix personnel deployed the TPL to depths ranging from 3000-6000 meters while listening for the black box pingers. TPL operations revealed several acoustic indications and, while not the same frequency as MH370 black box pingers, these acoustic indications were identified by crash investigators as worthy of further investigation. On 15 April Phoenix was tasked to commence AUV search operations in the area of the TPL identified acoustic indications. Over the next month and a half Artemis collected side scan sonar imagery of the seafloor in search of MH370 wreckage. At the conclusion of 70 operational days the Phoenix AUV had successfully searched 860 square kilometers, covering the prescribed search area, with no sign of aircraft debris. This result has since led crash investigators to conclude that the acoustic indications heard by the TPL were not from MH370 black box pingers. While this initial search did not result in the location of MH370, the operation did provide an exceptional demonstration of AUV technology. Throughout the search the vehicle provided high quality geo-referenced data containing clear imagery of the sea floor while working at depths as great as 5005 meters (a Bluefin 21 record). The search also included a 27 hour and 9 minute dive (another Bluefin 21 record). Despite not finding the aircraft, the successful collection of high quality data at extreme depths in a remote and unfamiliar part of the world is a noteworthy accomplishment and indicative of the future uses of AUV technology.
2014年3月21日，凤凰国际控股有限公司(Phoenix International Holdings, Inc.)受美国海军委托，通过一份为期多年的海军海上系统司令部(NAVSEA)合同，为马来西亚航空公司370航班(MH370)的失踪提供海底搜索服务。为了支持这项任务，凤凰号向澳大利亚珀斯部署了9名人员、海军拖曳ping信号定位器(TPL)和凤凰号蓝鳍21自主水下航行器(AUV)——一种名为Artemis的系统。搜索行动的初始阶段从4月4日至14日进行，使用TPL监听安装在飞机飞行数据记录仪和驾驶舱语音记录仪(黑匣子)上的盐水激活水下定位信标(ULB)“ping”。在珀斯西北约1600公里处的澳大利亚国防船(ADV)海盾号上，凤凰号的工作人员将TPL部署到3000-6000米的深度，同时监听黑匣子的ping信号。TPL操作发现了几个声音迹象，虽然频率与MH370黑匣子的ping信号不同，但坠机调查人员认为这些声音迹象值得进一步调查。4月15日，凤凰号受令在TPL识别出的声学指示区域开始AUV搜索行动。在接下来的一个半月里，阿尔忒弥斯收集了海底侧扫声纳图像，以寻找MH370残骸。在70天的行动结束时，凤凰号水下航行器成功搜索了860平方公里，覆盖了规定的搜索区域，没有发现飞机残骸的迹象。这一结果导致坠机调查人员得出结论，TPL听到的声音指示不是来自MH370黑匣子的ping信号。虽然最初的搜索并没有找到MH370的位置，但这次行动确实展示了水下航行器技术的非凡应用。在整个搜索过程中，该车辆提供了高质量的地理参考数据，其中包括海底的清晰图像，同时工作深度可达5005米(蓝鳍21的记录)。搜索还包括27小时9分钟的潜水(另一个蓝鳍21记录)。尽管没有找到飞机，但在世界偏远和陌生地区的极端深度成功收集高质量数据是一项值得注意的成就，并表明了水下航行器技术的未来应用。
{"title":"Deep ocean search for Malaysia airlines flight 370","authors":"Peter K. LeHardy, C. Moore","doi":"10.1109/OCEANS.2014.7003292","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003292","url":null,"abstract":"On 21 March 2014, Phoenix International Holdings, Inc. (Phoenix) was tasked by the U.S. Navy, through a multi-year Naval Sea Systems Command (NAVSEA) contract, to provide undersea search services in response to the disappearance of Malaysia Airlines Flight 370 (MH370). In support of this tasking, Phoenix deployed 9 personnel, the Navy's Towed Pinger Locator (TPL), and Phoenix's Bluefin 21 Autonomous Underwater Vehicle (AUV) - a system called Artemis - to Perth, Australia. The initial phase of the search operation took place from 04-14 April and involved using the TPL to listen for the saltwater activated Underwater Locator Beacon (ULB) “pingers” mounted to the plane's Flight Data Recorder and Cockpit Voice Recorder (the black boxes). Working aboard the Australian Defense Vessel (ADV) Ocean Shield roughly 1600 km North West of Perth, Phoenix personnel deployed the TPL to depths ranging from 3000-6000 meters while listening for the black box pingers. TPL operations revealed several acoustic indications and, while not the same frequency as MH370 black box pingers, these acoustic indications were identified by crash investigators as worthy of further investigation. On 15 April Phoenix was tasked to commence AUV search operations in the area of the TPL identified acoustic indications. Over the next month and a half Artemis collected side scan sonar imagery of the seafloor in search of MH370 wreckage. At the conclusion of 70 operational days the Phoenix AUV had successfully searched 860 square kilometers, covering the prescribed search area, with no sign of aircraft debris. This result has since led crash investigators to conclude that the acoustic indications heard by the TPL were not from MH370 black box pingers. While this initial search did not result in the location of MH370, the operation did provide an exceptional demonstration of AUV technology. Throughout the search the vehicle provided high quality geo-referenced data containing clear imagery of the sea floor while working at depths as great as 5005 meters (a Bluefin 21 record). The search also included a 27 hour and 9 minute dive (another Bluefin 21 record). Despite not finding the aircraft, the successful collection of high quality data at extreme depths in a remote and unfamiliar part of the world is a noteworthy accomplishment and indicative of the future uses of AUV technology.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129728194","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}
Pub Date : 2014-09-01DOI: 10.1109/OCEANS.2014.7003019
Bahareh Moshtagh, K. Hawboldt
Oil and gas operations have moved from conventional petroleum reserves to unconventional petroleum reserves such as remote offshore, deep Ocean and the Arctic. The management of oil spills is especially challenging due to these conditions. Oil spills are typically due to vessels accidents, tanker discharges, wells, offshore platforms, drilling wastes, or release of refined petroleum products and their by-products, heavier fuels and the spill of any waste oil. Oil spills impact human, plants and wild life including birds, fish and mammals, and therefore the response strategies must attempt to minimize the impact to multiple receptors. In Arctic environments, traditional mitigation and response to oil spill are less effective due to low water/air temperatures, ice cover, and other environmental conditions. Dispersants are a common response method; however there are issues with respect to toxicity and effectiveness of chemically derived dispersants. Biologically derived surfactants and dispersants, produced by naturally occurring bacteria, have some advantages including rapid biodegradation and low toxicity over the synthetic surfactants. However, large scale production is limited because of high costs associated with growth medium and operations. Cost effective production of biosurfactants could be achieved by using industrial wastes and by-products as media/substrate, thereby decreasing expensive medium costs and reducing the environmental impacts of the wastes. In this study the feasibility of glycerol, derived from the conversion of waste fish oil to biodiesel, as an effective carbon source for the production of biodispersants by indigenous Rhodococcus erythropolis and Bacillus subtilis strain is investigated Glycerol, a tribasic alcohol, is a byproduct of the biodiesel production process. Biodiesel is produced via the transesterification reaction of triglycerides in oils or fats and waste oils, with alcohols, in the presence of a homogeneous catalyst (chemical or enzymatic). In general, for every 10 kg of biodiesel produced approximately 1 kg of crude glycerol. As the production of biodiesel increases so will crude glycerol. The glycerol market is a saturated market already, and therefore any alternative market for this byproduct is advantageous to the larger scale production of biodiesel production. The waste stream ability to produce biosurfactant by indigenous Bacillus subtilis and Rhodococcus erythropolis strains will be determined. The cultivations will be performed in 250 mL flasks containing 50 ml medium at room temperature, and stirred in a rotary shaker at 30 C and 200 rpm for 3-4 days. Biosurfactant productivity will be evaluated by surface tension measurement and emulsification index (E24) determination as response variables. The produced biodispersants would have the ability to be used as an effective method to minimize the impacts of spilled oils in offshore Newfoundland and Labrador.
{"title":"Production of biodispersants for oil spill remediation in Harsh environment using glycerol from the conversion of fish oil to biodiesel","authors":"Bahareh Moshtagh, K. Hawboldt","doi":"10.1109/OCEANS.2014.7003019","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003019","url":null,"abstract":"Oil and gas operations have moved from conventional petroleum reserves to unconventional petroleum reserves such as remote offshore, deep Ocean and the Arctic. The management of oil spills is especially challenging due to these conditions. Oil spills are typically due to vessels accidents, tanker discharges, wells, offshore platforms, drilling wastes, or release of refined petroleum products and their by-products, heavier fuels and the spill of any waste oil. Oil spills impact human, plants and wild life including birds, fish and mammals, and therefore the response strategies must attempt to minimize the impact to multiple receptors. In Arctic environments, traditional mitigation and response to oil spill are less effective due to low water/air temperatures, ice cover, and other environmental conditions. Dispersants are a common response method; however there are issues with respect to toxicity and effectiveness of chemically derived dispersants. Biologically derived surfactants and dispersants, produced by naturally occurring bacteria, have some advantages including rapid biodegradation and low toxicity over the synthetic surfactants. However, large scale production is limited because of high costs associated with growth medium and operations. Cost effective production of biosurfactants could be achieved by using industrial wastes and by-products as media/substrate, thereby decreasing expensive medium costs and reducing the environmental impacts of the wastes. In this study the feasibility of glycerol, derived from the conversion of waste fish oil to biodiesel, as an effective carbon source for the production of biodispersants by indigenous Rhodococcus erythropolis and Bacillus subtilis strain is investigated Glycerol, a tribasic alcohol, is a byproduct of the biodiesel production process. Biodiesel is produced via the transesterification reaction of triglycerides in oils or fats and waste oils, with alcohols, in the presence of a homogeneous catalyst (chemical or enzymatic). In general, for every 10 kg of biodiesel produced approximately 1 kg of crude glycerol. As the production of biodiesel increases so will crude glycerol. The glycerol market is a saturated market already, and therefore any alternative market for this byproduct is advantageous to the larger scale production of biodiesel production. The waste stream ability to produce biosurfactant by indigenous Bacillus subtilis and Rhodococcus erythropolis strains will be determined. The cultivations will be performed in 250 mL flasks containing 50 ml medium at room temperature, and stirred in a rotary shaker at 30 C and 200 rpm for 3-4 days. Biosurfactant productivity will be evaluated by surface tension measurement and emulsification index (E24) determination as response variables. The produced biodispersants would have the ability to be used as an effective method to minimize the impacts of spilled oils in offshore Newfoundland and Labrador.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128530436","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}
Pub Date : 2014-09-01DOI: 10.1109/OCEANS.2014.7003264
Eric Cullen, R. Chumbinho, J. Breslin
The marine environment presents difficult challenges with respect to resilient real time communications. This paper details a system that has been developed to bring reliance, with no loss of data, to marine data acquisition systems.
{"title":"SmartBay Ireland's marine real time data acquisition system","authors":"Eric Cullen, R. Chumbinho, J. Breslin","doi":"10.1109/OCEANS.2014.7003264","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003264","url":null,"abstract":"The marine environment presents difficult challenges with respect to resilient real time communications. This paper details a system that has been developed to bring reliance, with no loss of data, to marine data acquisition systems.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127383864","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}
Pub Date : 2014-09-01DOI: 10.1109/OCEANS.2014.7003057
R. Guion, A. Young
The lifespan of a tidal turbine is strongly affected by the unsteady loading it experiences, so knowledge of the mean flow speed is not sufficient: unsteadiness must also be quantified. One of the most common turbulence measurement devices in the marine environment is the Acoustic Doppler Current Profiler (ADCP). The variance of steady velocity measurements from ADCPs has been studied in detail, but very little attention has been given to the fundamental limits of ADCPs in terms of the frequencies and lengthscales that they can capture. In this paper, it is shown that the ADCP acts as a low-pass filter to eddies and that even optimistic calculations predict significant attenuation at lengthscales up to ten times the blade chord of a typical tidal turbine. For a typical 40 m deep channel wavelengths below 3-4 m are attenuated by 90% or more. Those eddies that are not filtered out are then subject to a distortion that will either amplify or attenuate the signal depending on the precise turbulence characteristics of the site in question. While this low-pass filtering may alter some global statistics by truncating the observed spectrum, it is most damaging when data is extracted for particular frequencies, as a turbine designer may do when assessing unsteady loading and fatigue life. It is therefore recommended that high-resolution turbulence data, e.g. from a hotwire, is captured over part of the water column and that this is used to calibrate ADCP data.
{"title":"The frequency response of acoustic Doppler current profilers: Spatiotemporal response and implications for tidal turbine site assessment","authors":"R. Guion, A. Young","doi":"10.1109/OCEANS.2014.7003057","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003057","url":null,"abstract":"The lifespan of a tidal turbine is strongly affected by the unsteady loading it experiences, so knowledge of the mean flow speed is not sufficient: unsteadiness must also be quantified. One of the most common turbulence measurement devices in the marine environment is the Acoustic Doppler Current Profiler (ADCP). The variance of steady velocity measurements from ADCPs has been studied in detail, but very little attention has been given to the fundamental limits of ADCPs in terms of the frequencies and lengthscales that they can capture. In this paper, it is shown that the ADCP acts as a low-pass filter to eddies and that even optimistic calculations predict significant attenuation at lengthscales up to ten times the blade chord of a typical tidal turbine. For a typical 40 m deep channel wavelengths below 3-4 m are attenuated by 90% or more. Those eddies that are not filtered out are then subject to a distortion that will either amplify or attenuate the signal depending on the precise turbulence characteristics of the site in question. While this low-pass filtering may alter some global statistics by truncating the observed spectrum, it is most damaging when data is extracted for particular frequencies, as a turbine designer may do when assessing unsteady loading and fatigue life. It is therefore recommended that high-resolution turbulence data, e.g. from a hotwire, is captured over part of the water column and that this is used to calibrate ADCP data.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129927930","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}
Pub Date : 2014-09-01DOI: 10.1109/OCEANS.2014.7003149
S. Basagni, C. Petrioli, R. Petroccia, D. Spaccini
The paper presents a comparative performance evaluation of two routing protocols for underwater wireless sensor networks (UWSNs). The two protocols are the Channel-Aware Routing Protocol (CARP), exemplary of a cross layer approach to underwater routing, and a simple variation of common flooding, called EFlood, where performance is enhanced by introducing random re-transmission times. The scenarios we consider are obtained via simulations and from trials at sea performed under a collaboration agreement between the University of Roma “La Sapienza” and the NATO Science and Technology Organization Centre for Maritime Research and Experimentation (STO CMRE). Two sets of simulations results are shown where the physical layer is modeled by a ray-traced channel as well as by replaying real channel traces, under the same network configuration. Results are also reported from campaigns of experiments at sea. Comparing all results shows how channel replay mimics faithfully actual channel dynamics with respect to what is achievable through a simulated channel model, thus demonstrating the effectiveness of this technique for a fair and repeatable performance comparison of solutions for UWSNs.
{"title":"Channel replay-based performance evaluation of protocols for underwater routing","authors":"S. Basagni, C. Petrioli, R. Petroccia, D. Spaccini","doi":"10.1109/OCEANS.2014.7003149","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003149","url":null,"abstract":"The paper presents a comparative performance evaluation of two routing protocols for underwater wireless sensor networks (UWSNs). The two protocols are the Channel-Aware Routing Protocol (CARP), exemplary of a cross layer approach to underwater routing, and a simple variation of common flooding, called EFlood, where performance is enhanced by introducing random re-transmission times. The scenarios we consider are obtained via simulations and from trials at sea performed under a collaboration agreement between the University of Roma “La Sapienza” and the NATO Science and Technology Organization Centre for Maritime Research and Experimentation (STO CMRE). Two sets of simulations results are shown where the physical layer is modeled by a ray-traced channel as well as by replaying real channel traces, under the same network configuration. Results are also reported from campaigns of experiments at sea. Comparing all results shows how channel replay mimics faithfully actual channel dynamics with respect to what is achievable through a simulated channel model, thus demonstrating the effectiveness of this technique for a fair and repeatable performance comparison of solutions for UWSNs.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130094667","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}
Pub Date : 2014-09-01DOI: 10.1109/OCEANS.2014.7003002
I. Ridge, J. Flory, S. Banfield
In recent years several European rope testing laboratories either downsized or closed. But the demand for rope testing has increased, particularly for application specific testing which models service life conditions of ropes, chains and cables. Tension Technology International (TTI), a leading consultancy firm in the field, identified this need and set up a new testing company: TTI Testing in Wallingford, UK, to provide these services to the public. This paper discusses the special requirements for testing wire and fiber ropes, chains and cables. It describes TTI Testing's specialized test equipment. Finally, it presents case studies which show how a carefully designed testing program can be used to represent, replicate and understand rope behavior in service. This improves understanding can be used to improve rope design, predict service life and develop discard criteria, and thus lead to safer and more economical operation. The paper will be of particular interest to makers and users of wire and fiber rope, chain, and cables.
{"title":"New European rope test facility","authors":"I. Ridge, J. Flory, S. Banfield","doi":"10.1109/OCEANS.2014.7003002","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003002","url":null,"abstract":"In recent years several European rope testing laboratories either downsized or closed. But the demand for rope testing has increased, particularly for application specific testing which models service life conditions of ropes, chains and cables. Tension Technology International (TTI), a leading consultancy firm in the field, identified this need and set up a new testing company: TTI Testing in Wallingford, UK, to provide these services to the public. This paper discusses the special requirements for testing wire and fiber ropes, chains and cables. It describes TTI Testing's specialized test equipment. Finally, it presents case studies which show how a carefully designed testing program can be used to represent, replicate and understand rope behavior in service. This improves understanding can be used to improve rope design, predict service life and develop discard criteria, and thus lead to safer and more economical operation. The paper will be of particular interest to makers and users of wire and fiber rope, chain, and cables.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130801316","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}
Pub Date : 2014-09-01DOI: 10.1109/OCEANS.2014.7003262
C. Haldeman, D. Aragon, H. Roarty, J. Kohut, S. Glenn
Underwater gliders are a disruptive technology capable of transforming our understanding of the ocean. Efficient vehicle flight is critical for proper data collection, allowing successful completion of project goals. Slocum glider flights in less than 15 m of water have been only marginally successful, as use of deep water flight coefficients disables proper inflection at shallow depths. Groundings can damage sensors, degrade data, halt progress, and ultimately endanger the vehicle. To correct poor flight performance, sensor parameters responsible for inflection were individually analyzed and adjusted. Tests were conducted on repeated flights in the shallow state waters of New Jersey with glider RU28 while conducting dissolved oxygen surveys for the New Jersey Department of Environmental Protection (NJDEP) and the United States Environmental Protection Agency (USEPA); further verifications were conducted off the shoaling areas of Delaware with glider OTIS while searching for tagged sturgeon and sand tiger sharks. As a result of these tests, flight performance has been drastically improved, with efficient flight in 8 m of water, including several promising instances in water as shallow as 6 m. Prior to adjustments, gliders would make little forward progress and spend 50-100% of a flight segment grounded. With the new parameters loaded, groundings have been eliminated from coastal missions. Enabling shallow water flight for Slocum gliders allows vehicle operations in an area largely unexplored by this type of platform, opening up coastal areas to new project ideas and sampling schemes. Shallow water flight parameters can be shared with the community to increase sampling density in areas previously off limits to these vehicles.
{"title":"Enabling shallow water flight on Slocum gliders","authors":"C. Haldeman, D. Aragon, H. Roarty, J. Kohut, S. Glenn","doi":"10.1109/OCEANS.2014.7003262","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003262","url":null,"abstract":"Underwater gliders are a disruptive technology capable of transforming our understanding of the ocean. Efficient vehicle flight is critical for proper data collection, allowing successful completion of project goals. Slocum glider flights in less than 15 m of water have been only marginally successful, as use of deep water flight coefficients disables proper inflection at shallow depths. Groundings can damage sensors, degrade data, halt progress, and ultimately endanger the vehicle. To correct poor flight performance, sensor parameters responsible for inflection were individually analyzed and adjusted. Tests were conducted on repeated flights in the shallow state waters of New Jersey with glider RU28 while conducting dissolved oxygen surveys for the New Jersey Department of Environmental Protection (NJDEP) and the United States Environmental Protection Agency (USEPA); further verifications were conducted off the shoaling areas of Delaware with glider OTIS while searching for tagged sturgeon and sand tiger sharks. As a result of these tests, flight performance has been drastically improved, with efficient flight in 8 m of water, including several promising instances in water as shallow as 6 m. Prior to adjustments, gliders would make little forward progress and spend 50-100% of a flight segment grounded. With the new parameters loaded, groundings have been eliminated from coastal missions. Enabling shallow water flight for Slocum gliders allows vehicle operations in an area largely unexplored by this type of platform, opening up coastal areas to new project ideas and sampling schemes. Shallow water flight parameters can be shared with the community to increase sampling density in areas previously off limits to these vehicles.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"65 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128020107","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}
Pub Date : 2014-09-01DOI: 10.1109/OCEANS.2014.7003154
Laurice Janette Dagum, F. J. Corpuz, M. Soriano, J. Jauod, E. Capili, R. J. Judilla
This paper presents a unique system specifically made to capture and create image mosaics of flat, wide, and shallow coral reefs at the Tubbataha Reefs Natural Park to assist in the rapid assessment of the reef scars caused by the grounding of the USS Guardian last January 17, 2013. This system is composed of an array of underwater cameras coupled with a GPS and depth logging device, and a mosaicking algorithm to stitch the images. The algorithm color corrects the images before creating panoramic strips of images across cameras. Linear regression is applied to the pixel shifts to smoothen values overlooked by the cross correlation function. The strips are then stitched across time to form image mosaics using modified fast image labeling. With an overlap of at least 30% between image frames, strips formed from an array of three cameras cover a distance more than twice the distance covered by a single camera.
{"title":"Stitching algorithm applied to camera array images for the visualization of Tubbataha reef grounding scars","authors":"Laurice Janette Dagum, F. J. Corpuz, M. Soriano, J. Jauod, E. Capili, R. J. Judilla","doi":"10.1109/OCEANS.2014.7003154","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003154","url":null,"abstract":"This paper presents a unique system specifically made to capture and create image mosaics of flat, wide, and shallow coral reefs at the Tubbataha Reefs Natural Park to assist in the rapid assessment of the reef scars caused by the grounding of the USS Guardian last January 17, 2013. This system is composed of an array of underwater cameras coupled with a GPS and depth logging device, and a mosaicking algorithm to stitch the images. The algorithm color corrects the images before creating panoramic strips of images across cameras. Linear regression is applied to the pixel shifts to smoothen values overlooked by the cross correlation function. The strips are then stitched across time to form image mosaics using modified fast image labeling. With an overlap of at least 30% between image frames, strips formed from an array of three cameras cover a distance more than twice the distance covered by a single camera.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123161591","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}
Pub Date : 2014-09-01DOI: 10.1109/OCEANS.2014.7003282
T. Duda, W. Zhang, K. Helfrich, A. Newhall, Ying-Tsong Lin, J. Lynch, Pierre FJ Lermusiaux, P. Haley, J. Wilkin
Data-constrained dynamical ocean modeling for the purpose of detailed forecasting and prediction continues to evolve and improve in quality. Modeling methods and computational capabilities have each improved. The result is that mesoscale phenomena can be modeled with skill, given sufficient data. However, many submesoscale features are less well modeled and remain largely unpredicted from a deterministic event standpoint, and possibly also from a statistical property standpoint. A multi-institution project is underway with goals of uncovering more of the details of a few submesoscale processes, working toward better predictions of their occurrence and their variability. A further component of our project is application of the new ocean models to ocean acoustic modeling and prediction. This paper focuses on one portion of the ongoing work: Efforts to link nonhydrostatic-physics models of continental-shelf nonlinear internal wave evolution to data-driven regional models. Ocean front-related effects are also touched on.
{"title":"Issues and progress in the prediction of ocean submesoscale features and internal waves","authors":"T. Duda, W. Zhang, K. Helfrich, A. Newhall, Ying-Tsong Lin, J. Lynch, Pierre FJ Lermusiaux, P. Haley, J. Wilkin","doi":"10.1109/OCEANS.2014.7003282","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003282","url":null,"abstract":"Data-constrained dynamical ocean modeling for the purpose of detailed forecasting and prediction continues to evolve and improve in quality. Modeling methods and computational capabilities have each improved. The result is that mesoscale phenomena can be modeled with skill, given sufficient data. However, many submesoscale features are less well modeled and remain largely unpredicted from a deterministic event standpoint, and possibly also from a statistical property standpoint. A multi-institution project is underway with goals of uncovering more of the details of a few submesoscale processes, working toward better predictions of their occurrence and their variability. A further component of our project is application of the new ocean models to ocean acoustic modeling and prediction. This paper focuses on one portion of the ongoing work: Efforts to link nonhydrostatic-physics models of continental-shelf nonlinear internal wave evolution to data-driven regional models. Ocean front-related effects are also touched on.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126554184","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}
Pub Date : 2014-09-01DOI: 10.1109/OCEANS.2014.7003208
Wonwoo Lee, Jun-Ho Jeon, Sung-Joon Park
Small-scale underwater communication system, such as underwater wireless sensor network (UWSN), has been emerged as one of the promising research and development areas. For the use in limited inland waters, in this paper, we design and implement an underwater communication modem having the properties of small size, low-power consumption and moderate working distance and data rate. Channel impulse responses are investigated by means of both simulation and experiments in a pond and a lake in order to figure out the characteristics of underwater acoustics in confined aquatic spaces, and error performances are evaluated under several conditions. According to results, theoretical channel impulse responses are quite different from empirical ones due to shallow water depth and reflections by surrounding wall and aquatic ecosystem. Since the implemented micro-modem satisfies the requirements for short-range underwater communication systems, it could be utilized for various applications in underwater.
{"title":"Micro-modem for short-range underwater communication systems","authors":"Wonwoo Lee, Jun-Ho Jeon, Sung-Joon Park","doi":"10.1109/OCEANS.2014.7003208","DOIUrl":"https://doi.org/10.1109/OCEANS.2014.7003208","url":null,"abstract":"Small-scale underwater communication system, such as underwater wireless sensor network (UWSN), has been emerged as one of the promising research and development areas. For the use in limited inland waters, in this paper, we design and implement an underwater communication modem having the properties of small size, low-power consumption and moderate working distance and data rate. Channel impulse responses are investigated by means of both simulation and experiments in a pond and a lake in order to figure out the characteristics of underwater acoustics in confined aquatic spaces, and error performances are evaluated under several conditions. According to results, theoretical channel impulse responses are quite different from empirical ones due to shallow water depth and reflections by surrounding wall and aquatic ecosystem. Since the implemented micro-modem satisfies the requirements for short-range underwater communication systems, it could be utilized for various applications in underwater.","PeriodicalId":368693,"journal":{"name":"2014 Oceans - St. John's","volume":"599 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114066752","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}
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