Pub Date : 2011-12-19DOI: 10.23919/OCEANS.2011.6107256
Yen-Da Chen, Chun-Chih Li, Ruihai Dai, K. Shih
In terrestrial wireless networks, station (STA) adopts virtual carrier sensing mechanism to avoid hidden terminal problem. The neighbors which had received RTS/CTS will set a Network Allocation Vector (NAV) and suspend the transmission in NAV duration to avoid data collision. Due to the impacts of low data rate and long propagation delay, setting NAV duration in the underwater acoustic networks (UANs) is much difficult than that in the terrestrial wireless networks. A too short NAV duration such that the transmission data to be collided. A too long NAV duration leads the low bandwidth utilization such that low network throughput. In this paper, a stair-like NAV duration setting mechanism is proposed to set a precisely NAV duration on each STA. The proposed stair-like NAV duration setting can overcome the long propagation delay in UANs and minimize the suspended transmission time. Therefore, the stair-like NAV setting mechanism can enhance the network through and avoid the data to be collided.
{"title":"On enhancing four-way handshake with stair-like NAV setting for underwater acoustic networks","authors":"Yen-Da Chen, Chun-Chih Li, Ruihai Dai, K. Shih","doi":"10.23919/OCEANS.2011.6107256","DOIUrl":"https://doi.org/10.23919/OCEANS.2011.6107256","url":null,"abstract":"In terrestrial wireless networks, station (STA) adopts virtual carrier sensing mechanism to avoid hidden terminal problem. The neighbors which had received RTS/CTS will set a Network Allocation Vector (NAV) and suspend the transmission in NAV duration to avoid data collision. Due to the impacts of low data rate and long propagation delay, setting NAV duration in the underwater acoustic networks (UANs) is much difficult than that in the terrestrial wireless networks. A too short NAV duration such that the transmission data to be collided. A too long NAV duration leads the low bandwidth utilization such that low network throughput. In this paper, a stair-like NAV duration setting mechanism is proposed to set a precisely NAV duration on each STA. The proposed stair-like NAV duration setting can overcome the long propagation delay in UANs and minimize the suspended transmission time. Therefore, the stair-like NAV setting mechanism can enhance the network through and avoid the data to be collided.","PeriodicalId":19442,"journal":{"name":"OCEANS'11 MTS/IEEE KONA","volume":"21 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2011-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79975021","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 : 2011-12-19DOI: 10.23919/OCEANS.2011.6107052
Bin Yang, Lin Xiao, J. Jouffroy
Sailing vessels, due to their particular propulsive mechanism, gradually lose power as they face the wind, i.e. when they are in the so-called “no-go zone”. Interestingly, dynamical models of sailing vessels, which are usually quite complex, all have in common this no-go zone effect. Using a control-theoretic concept called backward reachable set, we demonstrate how a much simpler dynamic model that we proposed in an earlier study, has very similar dynamic properties as that of its most complex counterparts. This model comparison is done through theoretical validation and computation of their reachable sets.
{"title":"A control-theoretic outlook at the no-go zone in sailing vessels","authors":"Bin Yang, Lin Xiao, J. Jouffroy","doi":"10.23919/OCEANS.2011.6107052","DOIUrl":"https://doi.org/10.23919/OCEANS.2011.6107052","url":null,"abstract":"Sailing vessels, due to their particular propulsive mechanism, gradually lose power as they face the wind, i.e. when they are in the so-called “no-go zone”. Interestingly, dynamical models of sailing vessels, which are usually quite complex, all have in common this no-go zone effect. Using a control-theoretic concept called backward reachable set, we demonstrate how a much simpler dynamic model that we proposed in an earlier study, has very similar dynamic properties as that of its most complex counterparts. This model comparison is done through theoretical validation and computation of their reachable sets.","PeriodicalId":19442,"journal":{"name":"OCEANS'11 MTS/IEEE KONA","volume":"52 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2011-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76654889","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 : 2011-12-19DOI: 10.23919/OCEANS.2011.6106934
X. Bian, Chunhui Mou, Zheping Yan, Hongjian Wang
This paper addresses the problem of multi-AUV along given spatial paths with a given forward speed profile while holding a desired formation pattern in three-dimensional space. The decentralized controller is proposed to realize the coordinated path tracking of multiple AUVs. With this set-up, path tracking and speed coordination are designed decoupled. The kinernatic and dynamic path tracking controller is designed to reduce the position error and speed error between the vehicle and the virtual reference target, respectively. The algebraic graph theory is used to build complex underwater communication network. The coordination error model is established by the topology of the communication network. The coordination controller is designed to adjust the speed of virtual reference target so as to achieve a desired formation pattern.
{"title":"Formation coordinated control for multi-AUV based on spatial curve path tracking","authors":"X. Bian, Chunhui Mou, Zheping Yan, Hongjian Wang","doi":"10.23919/OCEANS.2011.6106934","DOIUrl":"https://doi.org/10.23919/OCEANS.2011.6106934","url":null,"abstract":"This paper addresses the problem of multi-AUV along given spatial paths with a given forward speed profile while holding a desired formation pattern in three-dimensional space. The decentralized controller is proposed to realize the coordinated path tracking of multiple AUVs. With this set-up, path tracking and speed coordination are designed decoupled. The kinernatic and dynamic path tracking controller is designed to reduce the position error and speed error between the vehicle and the virtual reference target, respectively. The algebraic graph theory is used to build complex underwater communication network. The coordination error model is established by the topology of the communication network. The coordination controller is designed to adjust the speed of virtual reference target so as to achieve a desired formation pattern.","PeriodicalId":19442,"journal":{"name":"OCEANS'11 MTS/IEEE KONA","volume":"45 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2011-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75978395","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 : 2011-12-19DOI: 10.23919/OCEANS.2011.6106923
K. Takagi, Y. Suyama, K. Kagaya
Recently, R&D of marine renewable energy becomes very popular all over the world. In this paper, the contra-rotating turbines are adopted as an ocean current power generator. The contra-rotating turbine system is theoretically torque free, since the second blade counters the first blade torque. Therefore, small main body and low cost mooring might be achieved. On the other hand, the motion control of the device may be necessary for a steady power supply, protection from fatigue damage of blade, and so on, because the blade size is larger than that of main body and thus the influence of unknown disturbances in the real sea is supposed to be big. In order to overcome this problem, the blade pitch control is utilized to control the motion of the device. The blade force and equation of motions are formulated and numerical simulation is performed based on these formulas to find theoretically how to change the blade pitch for motion control. A simple experiment with a scale model is also performed as the first step of the motion control. It is confirmed that it is possible to move the model perpendicular to the flow direction by the blade pitch control.
{"title":"An attempt to control the motion of floating current turbine by the pitch control","authors":"K. Takagi, Y. Suyama, K. Kagaya","doi":"10.23919/OCEANS.2011.6106923","DOIUrl":"https://doi.org/10.23919/OCEANS.2011.6106923","url":null,"abstract":"Recently, R&D of marine renewable energy becomes very popular all over the world. In this paper, the contra-rotating turbines are adopted as an ocean current power generator. The contra-rotating turbine system is theoretically torque free, since the second blade counters the first blade torque. Therefore, small main body and low cost mooring might be achieved. On the other hand, the motion control of the device may be necessary for a steady power supply, protection from fatigue damage of blade, and so on, because the blade size is larger than that of main body and thus the influence of unknown disturbances in the real sea is supposed to be big. In order to overcome this problem, the blade pitch control is utilized to control the motion of the device. The blade force and equation of motions are formulated and numerical simulation is performed based on these formulas to find theoretically how to change the blade pitch for motion control. A simple experiment with a scale model is also performed as the first step of the motion control. It is confirmed that it is possible to move the model perpendicular to the flow direction by the blade pitch control.","PeriodicalId":19442,"journal":{"name":"OCEANS'11 MTS/IEEE KONA","volume":"3 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2011-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76034348","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 : 2011-12-19DOI: 10.23919/OCEANS.2011.6107149
D. Sternlicht, Jose E. Fernandez, R. Holtzapple, Daniel P. Kucik, T. Montgomery, C. Loeffler
The U.S. Office of Naval Research is developing synthetic aperture sonars for the detection, localization, and classification of mines, for protection of sea lines of communication and Naval operating areas, and for support of amphibious operations. This paper reviews several evolving mine countermeasures sonars deployed on autonomous undersea vehicles that operate stand-alone and in coordination with complementary sensors, including the Small Synthetic Aperture Minehunter (SSAM), the Autonomous Topographic & Large Area Survey (ATLAS) sonar, and the Buried Object Scanning Sonar (BOSS).
{"title":"Advanced sonar technologies for autonomous mine countermeasures","authors":"D. Sternlicht, Jose E. Fernandez, R. Holtzapple, Daniel P. Kucik, T. Montgomery, C. Loeffler","doi":"10.23919/OCEANS.2011.6107149","DOIUrl":"https://doi.org/10.23919/OCEANS.2011.6107149","url":null,"abstract":"The U.S. Office of Naval Research is developing synthetic aperture sonars for the detection, localization, and classification of mines, for protection of sea lines of communication and Naval operating areas, and for support of amphibious operations. This paper reviews several evolving mine countermeasures sonars deployed on autonomous undersea vehicles that operate stand-alone and in coordination with complementary sensors, including the Small Synthetic Aperture Minehunter (SSAM), the Autonomous Topographic & Large Area Survey (ATLAS) sonar, and the Buried Object Scanning Sonar (BOSS).","PeriodicalId":19442,"journal":{"name":"OCEANS'11 MTS/IEEE KONA","volume":"9 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2011-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87530953","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 : 2011-12-19DOI: 10.23919/OCEANS.2011.6107116
Amber R. Bratcher, L. Connell, P. Millard
Paralytic shellfish poisoning (PSP) is a major human health issue that occurs worldwide. Species of the marine dinoflagellate genus Alexandrium can produce dangerous amounts of paralytic shellfish toxins responsible for PSP poisoning at extremely low cell densities. Current detection and identification methods for Alexandrium typically used by coastal managers are time-consuming, expensive, require special training, and are typically unable to distinguish between toxin-producing and non toxin-producing species. Therefore, there is a need for new methods to address these issues. We have developed a field-deployable method that uses surface plasmon resonance (SPR) and species-specific peptide nucleic acid probes to detect Alexandrium rRNA. This instrument has been tested using synthetic nucleotide sequences and validated against the industry-standard Biacore SPR instrument. This instrument can reliably discriminate between synthetic nucleotide sequences designed to mimic two species of Alexandrium found to co-occur in the Gulf of Maine, and also has a higher sensitivity to low nucleotide concentrations than the Biacore instrument.
{"title":"Portable biosensor detection of the harmful dinoflagellate Alexandrium using surface plasmon resonance and peptide nucleic acid probes","authors":"Amber R. Bratcher, L. Connell, P. Millard","doi":"10.23919/OCEANS.2011.6107116","DOIUrl":"https://doi.org/10.23919/OCEANS.2011.6107116","url":null,"abstract":"Paralytic shellfish poisoning (PSP) is a major human health issue that occurs worldwide. Species of the marine dinoflagellate genus Alexandrium can produce dangerous amounts of paralytic shellfish toxins responsible for PSP poisoning at extremely low cell densities. Current detection and identification methods for Alexandrium typically used by coastal managers are time-consuming, expensive, require special training, and are typically unable to distinguish between toxin-producing and non toxin-producing species. Therefore, there is a need for new methods to address these issues. We have developed a field-deployable method that uses surface plasmon resonance (SPR) and species-specific peptide nucleic acid probes to detect Alexandrium rRNA. This instrument has been tested using synthetic nucleotide sequences and validated against the industry-standard Biacore SPR instrument. This instrument can reliably discriminate between synthetic nucleotide sequences designed to mimic two species of Alexandrium found to co-occur in the Gulf of Maine, and also has a higher sensitivity to low nucleotide concentrations than the Biacore instrument.","PeriodicalId":19442,"journal":{"name":"OCEANS'11 MTS/IEEE KONA","volume":"48 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2011-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87978860","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 : 2011-12-19DOI: 10.23919/OCEANS.2011.6107040
Geol-Ju Kim, Dong-Su Lee, Sung-joon Park
For decades remotely-operated vehicles (ROVs) have been designed and implemented in various size and shape. Among them, very small-sized ROV which is called micro ROV has the working range with tens of meters and takes the place of divers. In this paper, we develop a micro ROV operating not by umbilical cable which is troublesome for movements but by wireless acoustic communication. The micro wireless ROV is designed to conduct the commands of movement and measurement from a remote user and to report the result. Experiments in water tanks have verified functional operations of the vehicle and shown the feasibility for applications.
{"title":"A micro wireless remotely-operated vehicle","authors":"Geol-Ju Kim, Dong-Su Lee, Sung-joon Park","doi":"10.23919/OCEANS.2011.6107040","DOIUrl":"https://doi.org/10.23919/OCEANS.2011.6107040","url":null,"abstract":"For decades remotely-operated vehicles (ROVs) have been designed and implemented in various size and shape. Among them, very small-sized ROV which is called micro ROV has the working range with tens of meters and takes the place of divers. In this paper, we develop a micro ROV operating not by umbilical cable which is troublesome for movements but by wireless acoustic communication. The micro wireless ROV is designed to conduct the commands of movement and measurement from a remote user and to report the result. Experiments in water tanks have verified functional operations of the vehicle and shown the feasibility for applications.","PeriodicalId":19442,"journal":{"name":"OCEANS'11 MTS/IEEE KONA","volume":"11 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2011-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86346270","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 : 2011-12-19DOI: 10.23919/OCEANS.2011.6107039
A. Gao, A. Techet
This paper details an exploration into the design of an aerial-aquatic robotic vessel. A compact robot that could both swim underwater and glide in the air above water has many potential applications in ocean exploration and mapping, surveillance, and forecasting. In the first phase of this project, we focus on mechanical design concepts that would enable the biomimetic production of adequate thrust underwater. A brief review of precedent research concerning robotic fish and hydrodynamics is first presented, followed by an in-depth analysis of the mathematical theory relevant to the project. A passive model of a flying fish was constructed and launched from approximately 1 ft. underwater to determine the forces associated with overcoming drag underwater and exiting the water. Based on this, A number of conceptual designs which would produce the motion necessary for propulsion were formulated and are discussed from a mechanical design perspective. Various conventional and non-conventional actuators are reviewed, as well as a control scheme for the concepts presented. We end with a discussion of the future directions for this project, as well as the key challenges that remain to be addressed.
{"title":"Design considerations for a robotic flying fish","authors":"A. Gao, A. Techet","doi":"10.23919/OCEANS.2011.6107039","DOIUrl":"https://doi.org/10.23919/OCEANS.2011.6107039","url":null,"abstract":"This paper details an exploration into the design of an aerial-aquatic robotic vessel. A compact robot that could both swim underwater and glide in the air above water has many potential applications in ocean exploration and mapping, surveillance, and forecasting. In the first phase of this project, we focus on mechanical design concepts that would enable the biomimetic production of adequate thrust underwater. A brief review of precedent research concerning robotic fish and hydrodynamics is first presented, followed by an in-depth analysis of the mathematical theory relevant to the project. A passive model of a flying fish was constructed and launched from approximately 1 ft. underwater to determine the forces associated with overcoming drag underwater and exiting the water. Based on this, A number of conceptual designs which would produce the motion necessary for propulsion were formulated and are discussed from a mechanical design perspective. Various conventional and non-conventional actuators are reviewed, as well as a control scheme for the concepts presented. We end with a discussion of the future directions for this project, as well as the key challenges that remain to be addressed.","PeriodicalId":19442,"journal":{"name":"OCEANS'11 MTS/IEEE KONA","volume":"31 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2011-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82890221","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 : 2011-12-19DOI: 10.23919/OCEANS.2011.6107033
S. X. Li, M. Dan, Guo Yong, Yichong Wei, G. Xiang
Sound field is described by sound pressure and velocity; this is different from the former concept. This paper has discussed the application of vertical sound intensity stream in shallow and low frequency sound field based on fast field program (FFP) model. The vector signal processing technique is analyzed from physical angle of view, and is made use of to judge the surface ship or submarine. For the past several decades, the sound wave had been simulated by many kinds of mathematical models, such as radial model, kraken model, parabola equation model, multipath expand model, FFP model and so on. These models adapt their own scope, run time, solving precision. FFP model calculates the sound filed by wave theory, and the result is shown as wave number integration, this process uses FFP model, the speed is faster than other models, the result covers both disperse pattern component and continuous pattern component, the result is exacter. In this paper the minor factor is ignored, the boundary and absorbing factor are taken into account.
{"title":"The application of vertical sound intensity in shallow and low frequency sound field","authors":"S. X. Li, M. Dan, Guo Yong, Yichong Wei, G. Xiang","doi":"10.23919/OCEANS.2011.6107033","DOIUrl":"https://doi.org/10.23919/OCEANS.2011.6107033","url":null,"abstract":"Sound field is described by sound pressure and velocity; this is different from the former concept. This paper has discussed the application of vertical sound intensity stream in shallow and low frequency sound field based on fast field program (FFP) model. The vector signal processing technique is analyzed from physical angle of view, and is made use of to judge the surface ship or submarine. For the past several decades, the sound wave had been simulated by many kinds of mathematical models, such as radial model, kraken model, parabola equation model, multipath expand model, FFP model and so on. These models adapt their own scope, run time, solving precision. FFP model calculates the sound filed by wave theory, and the result is shown as wave number integration, this process uses FFP model, the speed is faster than other models, the result covers both disperse pattern component and continuous pattern component, the result is exacter. In this paper the minor factor is ignored, the boundary and absorbing factor are taken into account.","PeriodicalId":19442,"journal":{"name":"OCEANS'11 MTS/IEEE KONA","volume":"104 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2011-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80541962","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 : 2011-12-19DOI: 10.23919/OCEANS.2011.6106957
Daniel Hugo, B. Howell, C. D'Este, G. Timms, C. Sharman, P. D. de Souza, S. Allen
The Tasmanian Marine Analysis Network (Tas-MAN) project has initiatives to reduce costs at every level of a marine sensor network; including hardware, deployment, maintenance, data management, and information delivery.
{"title":"Low-cost marine monitoring: From sensors to information delivery","authors":"Daniel Hugo, B. Howell, C. D'Este, G. Timms, C. Sharman, P. D. de Souza, S. Allen","doi":"10.23919/OCEANS.2011.6106957","DOIUrl":"https://doi.org/10.23919/OCEANS.2011.6106957","url":null,"abstract":"The Tasmanian Marine Analysis Network (Tas-MAN) project has initiatives to reduce costs at every level of a marine sensor network; including hardware, deployment, maintenance, data management, and information delivery.","PeriodicalId":19442,"journal":{"name":"OCEANS'11 MTS/IEEE KONA","volume":"1 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2011-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83168604","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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