Pub Date : 2016-11-01DOI: 10.1109/AUV.2016.7778718
Hangil Joe, Son-cheol Yu
We propose a robot, named Iceberg worm, clinging to lower surface of ice shelf (or iceberg) for ice thickness measurement. The key technologies of the proposed robot are 1) Inverse buoyancy setting and adjustable buoyancy control system; 2) Biomimetic legs and crampons like insects feet; 3) Non-contact laser-ultrasonic ranging system; 4) Acoustic-taxis navigation like positive photo-taxis of bugs. A distinguishing characteristic of the proposed system is non-contact ice thickness measurement system by using laser-induced ultrasound, which improves measurement method on the cold and non-homogeneous rough surface of ice. In this paper, we presented technical issues to develop the proposed robot and imaginary methodologies.
{"title":"Iceberg worm: Biomimetic AUV for sea ice thickness survey using non-contact laser ultrasonic method","authors":"Hangil Joe, Son-cheol Yu","doi":"10.1109/AUV.2016.7778718","DOIUrl":"https://doi.org/10.1109/AUV.2016.7778718","url":null,"abstract":"We propose a robot, named Iceberg worm, clinging to lower surface of ice shelf (or iceberg) for ice thickness measurement. The key technologies of the proposed robot are 1) Inverse buoyancy setting and adjustable buoyancy control system; 2) Biomimetic legs and crampons like insects feet; 3) Non-contact laser-ultrasonic ranging system; 4) Acoustic-taxis navigation like positive photo-taxis of bugs. A distinguishing characteristic of the proposed system is non-contact ice thickness measurement system by using laser-induced ultrasound, which improves measurement method on the cold and non-homogeneous rough surface of ice. In this paper, we presented technical issues to develop the proposed robot and imaginary methodologies.","PeriodicalId":416057,"journal":{"name":"2016 IEEE/OES Autonomous Underwater Vehicles (AUV)","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122510704","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 : 2016-11-01DOI: 10.1109/AUV.2016.7778671
K. Siantidis
The paper describes a Simultaneous Localization and Mapping (SLAM) system suitable for an autonomous underwater vehicle (AUV) equipped with a dead reckoning system and a side scan sonar (SSS). The system was developed with the intention to compensate position drifts of an AUV navigation system during a mission. The processing chain consists of an automatic landmark detector, an automatic data association module and the SLAM filter. This paper presents results showing that our onboard SLAM approach successfully reduces navigational drifts.
{"title":"Side scan sonar based onboard SLAM system for autonomous underwater vehicles","authors":"K. Siantidis","doi":"10.1109/AUV.2016.7778671","DOIUrl":"https://doi.org/10.1109/AUV.2016.7778671","url":null,"abstract":"The paper describes a Simultaneous Localization and Mapping (SLAM) system suitable for an autonomous underwater vehicle (AUV) equipped with a dead reckoning system and a side scan sonar (SSS). The system was developed with the intention to compensate position drifts of an AUV navigation system during a mission. The processing chain consists of an automatic landmark detector, an automatic data association module and the SLAM filter. This paper presents results showing that our onboard SLAM approach successfully reduces navigational drifts.","PeriodicalId":416057,"journal":{"name":"2016 IEEE/OES Autonomous Underwater Vehicles (AUV)","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115747986","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 : 2016-11-01DOI: 10.1109/AUV.2016.7778722
Daiwei Li, Zheng Zeng, Junliang Cao, Di Lu, Chengke Xiong, L. Lian
This paper presents the design and experimental evaluation of a bio-inspired underwater glider with undulatory fin, which is highly maneuverable and energy efficient and holds strong promise for long-duration monitoring of aquatic environments. A novel scheme is proposed for spatially explicit water column sampling using the bio-inspired underwater glider. The scheme using spiraling motion to sample each water column, followed by sawtooth motion toward the direction of the next water column. Once surfacing, the glider uses undulatory fin propulsion to reach the next column location. Comprehensive design for the bio-inspired underwater glider prototype, comprised of six individually-actuated fin, is provided. Experiments are performed in a test tank to investigate the performance and maneuverability of the bio-inspired underwater glider prototype via surface swimming.
{"title":"A bio-inspired underwater glider with undulatory fin for long-duration, spatially explicit water column sampling","authors":"Daiwei Li, Zheng Zeng, Junliang Cao, Di Lu, Chengke Xiong, L. Lian","doi":"10.1109/AUV.2016.7778722","DOIUrl":"https://doi.org/10.1109/AUV.2016.7778722","url":null,"abstract":"This paper presents the design and experimental evaluation of a bio-inspired underwater glider with undulatory fin, which is highly maneuverable and energy efficient and holds strong promise for long-duration monitoring of aquatic environments. A novel scheme is proposed for spatially explicit water column sampling using the bio-inspired underwater glider. The scheme using spiraling motion to sample each water column, followed by sawtooth motion toward the direction of the next water column. Once surfacing, the glider uses undulatory fin propulsion to reach the next column location. Comprehensive design for the bio-inspired underwater glider prototype, comprised of six individually-actuated fin, is provided. Experiments are performed in a test tank to investigate the performance and maneuverability of the bio-inspired underwater glider prototype via surface swimming.","PeriodicalId":416057,"journal":{"name":"2016 IEEE/OES Autonomous Underwater Vehicles (AUV)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115394288","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 : 2016-11-01DOI: 10.1109/AUV.2016.7778682
P. Maurya, E. de Sa, A. Dubey, N. Dabholkar, A. Pascoal
The Autonomous hovering profiler (AHP) presented here has its basis on the Controlled thruster driven profiler that was first conceptualized in US patent 6,786,087 [1] thereafter developed as a proven oceanographic profiler (the Autonomous Vertical Profiler- AVP) [2] that is being used in scientific programs at NIO, Goa. We have augmented the AVP by incorporating additional acoustic and pressure sensors together with a versatile hover /altitude control system that maintains the device at a constant altitude above the seabed or below the sea surface. By doing this the AHP can hover and follow the topography of the seabed or sea surface as it drifts under the action of ocean currents. The development has the potential of novel applications in coral and seabed photography, time tracking of surface phytoplankton blooms and to autonomously follow the gradients of physical variables of chlorophyll, temperature, and dissolved oxygen which have stable time varying vertical profile shapes.
{"title":"Autonomous hovering profiler","authors":"P. Maurya, E. de Sa, A. Dubey, N. Dabholkar, A. Pascoal","doi":"10.1109/AUV.2016.7778682","DOIUrl":"https://doi.org/10.1109/AUV.2016.7778682","url":null,"abstract":"The Autonomous hovering profiler (AHP) presented here has its basis on the Controlled thruster driven profiler that was first conceptualized in US patent 6,786,087 [1] thereafter developed as a proven oceanographic profiler (the Autonomous Vertical Profiler- AVP) [2] that is being used in scientific programs at NIO, Goa. We have augmented the AVP by incorporating additional acoustic and pressure sensors together with a versatile hover /altitude control system that maintains the device at a constant altitude above the seabed or below the sea surface. By doing this the AHP can hover and follow the topography of the seabed or sea surface as it drifts under the action of ocean currents. The development has the potential of novel applications in coral and seabed photography, time tracking of surface phytoplankton blooms and to autonomously follow the gradients of physical variables of chlorophyll, temperature, and dissolved oxygen which have stable time varying vertical profile shapes.","PeriodicalId":416057,"journal":{"name":"2016 IEEE/OES Autonomous Underwater Vehicles (AUV)","volume":"2015 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114722902","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 : 2016-11-01DOI: 10.1109/AUV.2016.7778660
Zhongben Zhu, Sau-Lon James Hu, Huajun Li
Although it was recognized that an unmanned underwater vehicle (UUV) in reality might experience changing ocean current along its mission trajectory, most published papers related to the single beacon underwater navigation assumed a constant ocean current over the whole duration. When this assumption is against the reality, those underwater tracking models not only will fail to adequately describe the change of ocean current over the duration, but also may introduce large error to their position estimation. In this paper, by including adequate ocean current uncertainty in the process model at each discrete time, the estimated ocean current can exhibit time-varying and location-dependent characteristics. The effect on the accuracy of underwater tracking due to the inclusion of the ocean current uncertainty is investigated through a kinematic model that treats the unknown effective sound velocity (ESV) as a state variable. In addition to the Kalman filter, the performance of the corresponding Rauch-Tung-Striebel (RTS) smoother is also studied. Both simulation and filed data are used to study the effect on the accuracy of underwater tracking.
{"title":"Effect on Kalman based underwater tracking due to ocean current uncertainty","authors":"Zhongben Zhu, Sau-Lon James Hu, Huajun Li","doi":"10.1109/AUV.2016.7778660","DOIUrl":"https://doi.org/10.1109/AUV.2016.7778660","url":null,"abstract":"Although it was recognized that an unmanned underwater vehicle (UUV) in reality might experience changing ocean current along its mission trajectory, most published papers related to the single beacon underwater navigation assumed a constant ocean current over the whole duration. When this assumption is against the reality, those underwater tracking models not only will fail to adequately describe the change of ocean current over the duration, but also may introduce large error to their position estimation. In this paper, by including adequate ocean current uncertainty in the process model at each discrete time, the estimated ocean current can exhibit time-varying and location-dependent characteristics. The effect on the accuracy of underwater tracking due to the inclusion of the ocean current uncertainty is investigated through a kinematic model that treats the unknown effective sound velocity (ESV) as a state variable. In addition to the Kalman filter, the performance of the corresponding Rauch-Tung-Striebel (RTS) smoother is also studied. Both simulation and filed data are used to study the effect on the accuracy of underwater tracking.","PeriodicalId":416057,"journal":{"name":"2016 IEEE/OES Autonomous Underwater Vehicles (AUV)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123276304","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 : 2016-11-01DOI: 10.1109/AUV.2016.7778675
Ron Lewis, N. Bose, Sara Lewis, P. King, D. Walker, R. Devillers, Nick Ridgley, T. Husain, J. Munroe, A. Vardy
Autonomous Underwater Vehicle (AUV) technology has significant research potential, specifically for harsh maritime environment operations. Memorial University of Newfoundland recognized this potential and in 2005 the University commissioned an International Submarine Engineering Explorer AUV to be built. The Marine Environmental Research Lab for Intelligent Vehicles (MERLIN) was established to manage, maintain and operate the Explorer for Memorial University and any other potential AUV users. Over the course of ten years, MERLIN capabilities have grown to a full service AUV research team with harsh maritime and polar experiences. The Explorer was born in the Pacific Ocean, lives in the Atlantic Ocean and has vacationed in the Arctic. AUV research efforts have evolved from dynamic vehicle studies with basic sensor technology to integration of cutting edge sonar systems that push the boundaries of AUV design and successful implementations of original research into advanced autonomous navigation.
{"title":"MERLIN - A decade of large AUV experience at Memorial University of Newfoundland","authors":"Ron Lewis, N. Bose, Sara Lewis, P. King, D. Walker, R. Devillers, Nick Ridgley, T. Husain, J. Munroe, A. Vardy","doi":"10.1109/AUV.2016.7778675","DOIUrl":"https://doi.org/10.1109/AUV.2016.7778675","url":null,"abstract":"Autonomous Underwater Vehicle (AUV) technology has significant research potential, specifically for harsh maritime environment operations. Memorial University of Newfoundland recognized this potential and in 2005 the University commissioned an International Submarine Engineering Explorer AUV to be built. The Marine Environmental Research Lab for Intelligent Vehicles (MERLIN) was established to manage, maintain and operate the Explorer for Memorial University and any other potential AUV users. Over the course of ten years, MERLIN capabilities have grown to a full service AUV research team with harsh maritime and polar experiences. The Explorer was born in the Pacific Ocean, lives in the Atlantic Ocean and has vacationed in the Arctic. AUV research efforts have evolved from dynamic vehicle studies with basic sensor technology to integration of cutting edge sonar systems that push the boundaries of AUV design and successful implementations of original research into advanced autonomous navigation.","PeriodicalId":416057,"journal":{"name":"2016 IEEE/OES Autonomous Underwater Vehicles (AUV)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123585615","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 : 2016-11-01DOI: 10.1109/AUV.2016.7778673
G. Rui, M. Chitre
Cooperative multi-AUV localization has the potential to outperform single-AUV localization, by taking advantage of data sharing among the team members. Unlike terrestrial communication links, underwater communication links have many issues pertaining to the channel stability and bandwidth, and therefore a decentralized localization is preferred. However this opens up new challenges to team members working in cooperation. This paper uses analytical examples to illustrate the cooperation problems in the decentralized architecture. To solve these problems, we propose a new cooperative multi-AUV localization algorithm using distributed extended information filter (DEIF). The proposed method only requires small transmission packets and is designed for use under constrained underwater communication. It is robust to packet loss, providing consistent position estimates when fusing correlated data. We demonstrate the effectiveness and advantages of the proposed method with comparative results using data from simulation and field experiments.
{"title":"Cooperative multi-AUV localization using distributed extended information filter","authors":"G. Rui, M. Chitre","doi":"10.1109/AUV.2016.7778673","DOIUrl":"https://doi.org/10.1109/AUV.2016.7778673","url":null,"abstract":"Cooperative multi-AUV localization has the potential to outperform single-AUV localization, by taking advantage of data sharing among the team members. Unlike terrestrial communication links, underwater communication links have many issues pertaining to the channel stability and bandwidth, and therefore a decentralized localization is preferred. However this opens up new challenges to team members working in cooperation. This paper uses analytical examples to illustrate the cooperation problems in the decentralized architecture. To solve these problems, we propose a new cooperative multi-AUV localization algorithm using distributed extended information filter (DEIF). The proposed method only requires small transmission packets and is designed for use under constrained underwater communication. It is robust to packet loss, providing consistent position estimates when fusing correlated data. We demonstrate the effectiveness and advantages of the proposed method with comparative results using data from simulation and field experiments.","PeriodicalId":416057,"journal":{"name":"2016 IEEE/OES Autonomous Underwater Vehicles (AUV)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134607735","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 : 2016-11-01DOI: 10.1109/AUV.2016.7778669
M. Massot-Campos, G. Oliver, A. Bodenmann, B. Thornton
This article presents a bathymetric SLAM (simultaneous localization and mapping) solution for underwater vehicles by addressing the registration of point clouds gathered from single line laser-based structured light systems. While structured light can be applied to generate millimetre resolution seafloor bathymetry, the accuracy of the maps generated is typically constrained by the localization accuracy of the vehicles used. In this work, relative uncertainties in vehicle localisation are reduced by implementing bathymetric SLAM using temporally constrained submaps. We demonstrate that the method described can overcome misalignments by correcting errors in localisation and can be used to generate self-consistent high-resolution seafloor bathymetric maps.
{"title":"Submap bathymetric SLAM using structured light in underwater environments","authors":"M. Massot-Campos, G. Oliver, A. Bodenmann, B. Thornton","doi":"10.1109/AUV.2016.7778669","DOIUrl":"https://doi.org/10.1109/AUV.2016.7778669","url":null,"abstract":"This article presents a bathymetric SLAM (simultaneous localization and mapping) solution for underwater vehicles by addressing the registration of point clouds gathered from single line laser-based structured light systems. While structured light can be applied to generate millimetre resolution seafloor bathymetry, the accuracy of the maps generated is typically constrained by the localization accuracy of the vehicles used. In this work, relative uncertainties in vehicle localisation are reduced by implementing bathymetric SLAM using temporally constrained submaps. We demonstrate that the method described can overcome misalignments by correcting errors in localisation and can be used to generate self-consistent high-resolution seafloor bathymetric maps.","PeriodicalId":416057,"journal":{"name":"2016 IEEE/OES Autonomous Underwater Vehicles (AUV)","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132148871","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 : 2016-11-01DOI: 10.1109/AUV.2016.7778715
Minsung Sung, Son-cheol Yu
Underwater environment which has swift current is difficult area to explore with AUV. Because of swift current, AUV could be swept by current losing control of itself. TreeBot is designed to explore the area which has swift current. TreeBot consist of two parts; anchor and mini ROVs. Anchor is fixed on floor of ocean and protect TreeBot from being swept. Then, mini ROVs are launched from anchor and collect information about underwater environment.
{"title":"Mini ROV based anchoring AUV system TreeBot AUV","authors":"Minsung Sung, Son-cheol Yu","doi":"10.1109/AUV.2016.7778715","DOIUrl":"https://doi.org/10.1109/AUV.2016.7778715","url":null,"abstract":"Underwater environment which has swift current is difficult area to explore with AUV. Because of swift current, AUV could be swept by current losing control of itself. TreeBot is designed to explore the area which has swift current. TreeBot consist of two parts; anchor and mini ROVs. Anchor is fixed on floor of ocean and protect TreeBot from being swept. Then, mini ROVs are launched from anchor and collect information about underwater environment.","PeriodicalId":416057,"journal":{"name":"2016 IEEE/OES Autonomous Underwater Vehicles (AUV)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133099445","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 : 2016-11-01DOI: 10.1109/AUV.2016.7778713
Mohammad Fahmi Amri Bin Mohd Murad, Z. Ismail, Mohamed Idzham Bin Samah, K. Sammut
With the arrival of new robotic technologies such as an Autonomous Underwater Vehicle (AUV), a number of tasks that cannot be done by human now can be accomplished and bring human to reach the dangerous and unreachable areas. An AUV can be related to the most invention which can reduce human's work using specialized equipment and devices that control and perform the particular tasks. Therefore, it is able to fulfil the predetermined task without any human control and to react against unexpected situation by its artificial intelligence. This paper examines the effectiveness of using AUV as surveillance system for coral reef ecology. We propose a new AUV that ease researcher or activist to survey the condition of coral reef ecology environment.
{"title":"Surveillance of coral reef development using an Autonomous Underwater Vehicle","authors":"Mohammad Fahmi Amri Bin Mohd Murad, Z. Ismail, Mohamed Idzham Bin Samah, K. Sammut","doi":"10.1109/AUV.2016.7778713","DOIUrl":"https://doi.org/10.1109/AUV.2016.7778713","url":null,"abstract":"With the arrival of new robotic technologies such as an Autonomous Underwater Vehicle (AUV), a number of tasks that cannot be done by human now can be accomplished and bring human to reach the dangerous and unreachable areas. An AUV can be related to the most invention which can reduce human's work using specialized equipment and devices that control and perform the particular tasks. Therefore, it is able to fulfil the predetermined task without any human control and to react against unexpected situation by its artificial intelligence. This paper examines the effectiveness of using AUV as surveillance system for coral reef ecology. We propose a new AUV that ease researcher or activist to survey the condition of coral reef ecology environment.","PeriodicalId":416057,"journal":{"name":"2016 IEEE/OES Autonomous Underwater Vehicles (AUV)","volume":"206 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116197502","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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