Nauticos Corporation under a CRADA (Cooperative Research and Development Agreement) provides renavigation technology to the United States Navy. This technology enables ocean explorers to locate objects on the seabed. In a test of this new technology, a Navy team used this capability to discover the site of the Imperial Japanese fleet sunk at the Battle of Midway. In the first of three phases, the purpose of Midway I was to discover the location of at least one of the four Japanese aircraft carriers sunk at Midway. Analysis of data included a detailed navigation reconstruction using Nauticos' proprietary Kalman filter-based navigation analysis software, RENAV/sup TM/. With an understanding of general navigation principles, familiarity of ship's performance data, and sophisticated modeling techniques, Nauticos analysts were able to identify and quantify navigation errors in the data. Modern day underwater explorers are able to locate objects on the seabed today with much greater precision and confidence than ever before. This technology makes possible the discovery of many important historical and cultural sites which are now lost under the ocean.
{"title":"Midway I: the survey of a historical battle site","authors":"J. Palshook, S. King, C. Ingram","doi":"10.1109/UT.2000.852508","DOIUrl":"https://doi.org/10.1109/UT.2000.852508","url":null,"abstract":"Nauticos Corporation under a CRADA (Cooperative Research and Development Agreement) provides renavigation technology to the United States Navy. This technology enables ocean explorers to locate objects on the seabed. In a test of this new technology, a Navy team used this capability to discover the site of the Imperial Japanese fleet sunk at the Battle of Midway. In the first of three phases, the purpose of Midway I was to discover the location of at least one of the four Japanese aircraft carriers sunk at Midway. Analysis of data included a detailed navigation reconstruction using Nauticos' proprietary Kalman filter-based navigation analysis software, RENAV/sup TM/. With an understanding of general navigation principles, familiarity of ship's performance data, and sophisticated modeling techniques, Nauticos analysts were able to identify and quantify navigation errors in the data. Modern day underwater explorers are able to locate objects on the seabed today with much greater precision and confidence than ever before. This technology makes possible the discovery of many important historical and cultural sites which are now lost under the ocean.","PeriodicalId":397110,"journal":{"name":"Proceedings of the 2000 International Symposium on Underwater Technology (Cat. No.00EX418)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125683985","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}
For applications of robots in industrial underwater environments sensor systems are required to identify the observed scene and to determine the position of the tool-center-point (TCP) of robots. A laser radar for guidance of a mobile underwater vehicle is based on a different absorption distance measurement method, which calculates the distance by the different attenuation behaviour of water at two different laserlight wavelengths. Therefore, scattering and attenuation processes in water have to be incorporated. An ultrasonic measurement system is built as a trilateration system. It consists of piezoactuators and uses a time-of-flight method combined with a phase-shift measurement. Thus it is possible to identify the exact position and orientation of the actuator of an underwater robot with a very high accuracy.
{"title":"Sensor systems for robotic applications under water","authors":"H. Tonshoff, E. Bedhief, U. Kruse","doi":"10.1109/UT.2000.852567","DOIUrl":"https://doi.org/10.1109/UT.2000.852567","url":null,"abstract":"For applications of robots in industrial underwater environments sensor systems are required to identify the observed scene and to determine the position of the tool-center-point (TCP) of robots. A laser radar for guidance of a mobile underwater vehicle is based on a different absorption distance measurement method, which calculates the distance by the different attenuation behaviour of water at two different laserlight wavelengths. Therefore, scattering and attenuation processes in water have to be incorporated. An ultrasonic measurement system is built as a trilateration system. It consists of piezoactuators and uses a time-of-flight method combined with a phase-shift measurement. Thus it is possible to identify the exact position and orientation of the actuator of an underwater robot with a very high accuracy.","PeriodicalId":397110,"journal":{"name":"Proceedings of the 2000 International Symposium on Underwater Technology (Cat. No.00EX418)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131888325","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}
H. Fujimoto, K. Koizumi, M. Watanabe, A. Oshida, T. Furuta, N. Takamura, T. Ura
We have developed a compact gravimeter for measurement on board an AUV called R-One Robot. The gravity sensor is a special model of Scintrex gravimeter CG-3M with operating range of 27 gals. The gravity sensor is stabilized with signals from an optical gyroscope. The gravimeter has been tested and examined on a diagnostic table and surface ships anchored in a harbor as well as on the R-One Robot. Resolution of gravimetry is the order of 1 mgal (10/sup -6/ G); a few problems remain to be solved.
{"title":"Underwater gravimeter on board the R-One robot","authors":"H. Fujimoto, K. Koizumi, M. Watanabe, A. Oshida, T. Furuta, N. Takamura, T. Ura","doi":"10.1109/UT.2000.852559","DOIUrl":"https://doi.org/10.1109/UT.2000.852559","url":null,"abstract":"We have developed a compact gravimeter for measurement on board an AUV called R-One Robot. The gravity sensor is a special model of Scintrex gravimeter CG-3M with operating range of 27 gals. The gravity sensor is stabilized with signals from an optical gyroscope. The gravimeter has been tested and examined on a diagnostic table and surface ships anchored in a harbor as well as on the R-One Robot. Resolution of gravimetry is the order of 1 mgal (10/sup -6/ G); a few problems remain to be solved.","PeriodicalId":397110,"journal":{"name":"Proceedings of the 2000 International Symposium on Underwater Technology (Cat. No.00EX418)","volume":"131 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121564710","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}
We have developed an autonomous underwater vehicle (AUV), which can be used for lake environment monitoring. The length of the AUV is 2 m, its weight in air is 180 kg, and its maximum speed in water is 2 knots. It has two major missions: one is to monitor plankton distribution in the epilimnion by using its on-board submersible microscope, and the other is to monitor water quality in the benthic boundary layer by using a CTD instrument equipped with multiple sensors. The obtained data and images are transmitted to a surface research vessel (R/V) by ultrasonic waves, and subsequently transferred from the R/V to our base institute (Lake Biwa Research Institute) by a satellite mobile phone data link. We are expecting that this AUV will contribute to solving serious problems occurring in Lake Biwa such as cyanobacteria blooms in the epilimnion, and oxygen depletion in the benthic boundary.
{"title":"New AUV designed for lake environment monitoring","authors":"M. Kumagai, T. Ura, Y. Kuroda, R. Walker","doi":"10.1109/UT.2000.852519","DOIUrl":"https://doi.org/10.1109/UT.2000.852519","url":null,"abstract":"We have developed an autonomous underwater vehicle (AUV), which can be used for lake environment monitoring. The length of the AUV is 2 m, its weight in air is 180 kg, and its maximum speed in water is 2 knots. It has two major missions: one is to monitor plankton distribution in the epilimnion by using its on-board submersible microscope, and the other is to monitor water quality in the benthic boundary layer by using a CTD instrument equipped with multiple sensors. The obtained data and images are transmitted to a surface research vessel (R/V) by ultrasonic waves, and subsequently transferred from the R/V to our base institute (Lake Biwa Research Institute) by a satellite mobile phone data link. We are expecting that this AUV will contribute to solving serious problems occurring in Lake Biwa such as cyanobacteria blooms in the epilimnion, and oxygen depletion in the benthic boundary.","PeriodicalId":397110,"journal":{"name":"Proceedings of the 2000 International Symposium on Underwater Technology (Cat. No.00EX418)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125174195","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}
An ocean bottom broadband seismometer (OBBS) was installed 2170 m deep on the slope of the Ryukyu Trench with other sensors through the VENUS project. Prior to the installation of the OBBS unit, the bottom telemetry system, which supplies electrical power to the instruments, telemetry system and cable was installed on the ocean bottom by a method similar to cable repair works. Since broadband seismometers are extremely fragile, it was handled with special care. The installation of the seismometer was done by use of a deep-tow system and the ROV Kaiko-10 K. In September 1999, the OBBS unit was deployed at the target position, at 80-meter from the bottom telemetry system, with several meters allowances using a deep-tow system. To install the instrument at the exact location, the mother ship of the deep-tow system was precisely navigated. The connecting cable and eight weights were also dropped from the deep-tow system. The ROV Kaiko-10 K extended the 100 m-long connecting cable from the seismometer to the junction box and connected it to the junction box. The OBBS unit collected one and half month records. Several significant earthquakes near Japan, in Taiwan and San Francisco have been observed since the installation.
{"title":"Installation of high precision seismometer unit at the Ryukyu Trench using Guam-Okinawa geophysical submarine cable (GOGC: FOMER TPC-2 cable)","authors":"J. Kasahara, K. Kawaguchi, R. Iwase, Y. Shirasaki","doi":"10.1109/UT.2000.852573","DOIUrl":"https://doi.org/10.1109/UT.2000.852573","url":null,"abstract":"An ocean bottom broadband seismometer (OBBS) was installed 2170 m deep on the slope of the Ryukyu Trench with other sensors through the VENUS project. Prior to the installation of the OBBS unit, the bottom telemetry system, which supplies electrical power to the instruments, telemetry system and cable was installed on the ocean bottom by a method similar to cable repair works. Since broadband seismometers are extremely fragile, it was handled with special care. The installation of the seismometer was done by use of a deep-tow system and the ROV Kaiko-10 K. In September 1999, the OBBS unit was deployed at the target position, at 80-meter from the bottom telemetry system, with several meters allowances using a deep-tow system. To install the instrument at the exact location, the mother ship of the deep-tow system was precisely navigated. The connecting cable and eight weights were also dropped from the deep-tow system. The ROV Kaiko-10 K extended the 100 m-long connecting cable from the seismometer to the junction box and connected it to the junction box. The OBBS unit collected one and half month records. Several significant earthquakes near Japan, in Taiwan and San Francisco have been observed since the installation.","PeriodicalId":397110,"journal":{"name":"Proceedings of the 2000 International Symposium on Underwater Technology (Cat. No.00EX418)","volume":"189 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115423508","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}
The rubble leveling that accompanies the base mound construction for breakwaters and embankments takes place in demanding underwater environments involving extremely high risks. There is also concern about labor shortages and aging of divers. Moreover, harbor development sites have extended farther offshore in recent years, making it necessary to cope with more treacherous weather and deep-water conditions. Under these circumstances, in efforts to ensure safety and to shorten the process by speeding up operations, the demand for a safe underwater construction machine that can perform such tasks has been growing. In response to such demands, the "underwater backhoe", which mechanizes manual work performed by divers, has been developed. The device excels at tasks such as armor-stone leveling and rubble leveling required for base mound construction for breakwaters and embankments. This paper provides a background of underwater backhoe development and presents an overview of existing backhoes. It also introduces several instances of use in underwater work and considers several problems and areas for improvement.
{"title":"The development and utilization of the \"underwater backhoe,\" a multifunctional underwater construction machine","authors":"M. Ishii, S. Oshiro, T. Itoh","doi":"10.1109/UT.2000.852564","DOIUrl":"https://doi.org/10.1109/UT.2000.852564","url":null,"abstract":"The rubble leveling that accompanies the base mound construction for breakwaters and embankments takes place in demanding underwater environments involving extremely high risks. There is also concern about labor shortages and aging of divers. Moreover, harbor development sites have extended farther offshore in recent years, making it necessary to cope with more treacherous weather and deep-water conditions. Under these circumstances, in efforts to ensure safety and to shorten the process by speeding up operations, the demand for a safe underwater construction machine that can perform such tasks has been growing. In response to such demands, the \"underwater backhoe\", which mechanizes manual work performed by divers, has been developed. The device excels at tasks such as armor-stone leveling and rubble leveling required for base mound construction for breakwaters and embankments. This paper provides a background of underwater backhoe development and presents an overview of existing backhoes. It also introduces several instances of use in underwater work and considers several problems and areas for improvement.","PeriodicalId":397110,"journal":{"name":"Proceedings of the 2000 International Symposium on Underwater Technology (Cat. No.00EX418)","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115463455","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}
Unexpectedly high underwater electric field (UEF) signatures of ships have been reported, and detection of ships by their UEF signatures is known to be effective. For the purpose of cost-effective and reliable method to estimate UEF signatures of actual ships in open sea, we developed a method to measure underwater electric potential (UEP) from the deck of the ship. Two reference electrodes were hung down into water from the deck side. By fixing one of the electrodes near the stem of the ship, we measured the UEP at several points by another electrode around the ship in the depth of one meter. We then measured the UEP for the two ships, and the ratio of UEP of two ships agreed with that of UEF signatures measured with the sensors on the seafloor. We confirmed that the proposed method to measure UEP of actual ships is effective.
{"title":"A method to measure ship's underwater electric field from deck","authors":"M. Hirota","doi":"10.1109/UT.2000.852547","DOIUrl":"https://doi.org/10.1109/UT.2000.852547","url":null,"abstract":"Unexpectedly high underwater electric field (UEF) signatures of ships have been reported, and detection of ships by their UEF signatures is known to be effective. For the purpose of cost-effective and reliable method to estimate UEF signatures of actual ships in open sea, we developed a method to measure underwater electric potential (UEP) from the deck of the ship. Two reference electrodes were hung down into water from the deck side. By fixing one of the electrodes near the stem of the ship, we measured the UEP at several points by another electrode around the ship in the depth of one meter. We then measured the UEP for the two ships, and the ratio of UEP of two ships agreed with that of UEF signatures measured with the sensors on the seafloor. We confirmed that the proposed method to measure UEP of actual ships is effective.","PeriodicalId":397110,"journal":{"name":"Proceedings of the 2000 International Symposium on Underwater Technology (Cat. No.00EX418)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129289656","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}
It has been proposed to use gravitational field maps to correct navigational errors inherent in some navigational systems presently in use on unmanned underwater vehicles (UUV) and that such a technology might form the basis for a new UUV navigational system. However, the accuracy and usefulness of the navigational solution depends, among other things, on the accuracy of the gravitational field maps. Since gravitational fields are generally sparsely and irregularly sampled, mapping algorithms must be used to construct the field maps. To assess the impact of field maps computed from sparse sets of data on the accuracy of the navigational solution, the kriging algorithm is used to compute field maps with various grid spacings from both simulated and measured field data. Then position and bearing errors are simulated and the various field maps are used to obtain corrected navigational fixes. To assess the impact of the density of the field data on the accuracy of the navigational fix, the simulated data are sub-sampled and the process is repeated. Numerical results are shown that demonstrate some of the effects of grid spacing and data density on the accuracy of the navigational fix and that gravitational field maps may be used to provide a very accurate navigational fix.
{"title":"Gravitational field maps and navigational errors","authors":"G. Bishop","doi":"10.1109/UT.2000.852532","DOIUrl":"https://doi.org/10.1109/UT.2000.852532","url":null,"abstract":"It has been proposed to use gravitational field maps to correct navigational errors inherent in some navigational systems presently in use on unmanned underwater vehicles (UUV) and that such a technology might form the basis for a new UUV navigational system. However, the accuracy and usefulness of the navigational solution depends, among other things, on the accuracy of the gravitational field maps. Since gravitational fields are generally sparsely and irregularly sampled, mapping algorithms must be used to construct the field maps. To assess the impact of field maps computed from sparse sets of data on the accuracy of the navigational solution, the kriging algorithm is used to compute field maps with various grid spacings from both simulated and measured field data. Then position and bearing errors are simulated and the various field maps are used to obtain corrected navigational fixes. To assess the impact of the density of the field data on the accuracy of the navigational fix, the simulated data are sub-sampled and the process is repeated. Numerical results are shown that demonstrate some of the effects of grid spacing and data density on the accuracy of the navigational fix and that gravitational field maps may be used to provide a very accurate navigational fix.","PeriodicalId":397110,"journal":{"name":"Proceedings of the 2000 International Symposium on Underwater Technology (Cat. No.00EX418)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129209186","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}
Proposes a method for underwater target tracking using optical data, which consists of color, texture, shape and dynamic properties of the environment. Here, how the dynamic properties from image sequences can be used for target tracking by autonomous underwater vehicles (AUVs) is studied. Optical flow techniques are used to derive the dynamics of the images. The objects of interest are extracted from the images by using the dynamical properties and their optical features. The consecutive dynamic behavior of objects of interest is estimated based on the current dynamics. Using the predicted dynamics, the region of interest (ROI) in the image can be identified reducing the amount of data to be processed. This increases the speed of processing using the hardware available in small pressure hulls. Image dynamics and feature position information fused with other on-board sensor information, the navigational commands for the AUV are derived. In the paper, the extraction of objects of interest from the images based on dynamic vision is presented and the performance of this method for underwater target tracking is demonstrated by experimental results.
{"title":"Autonomous target tracking by AUVs using dynamic vision","authors":"Yang Fan, Arjuna Balasuriya","doi":"10.1109/UT.2000.852539","DOIUrl":"https://doi.org/10.1109/UT.2000.852539","url":null,"abstract":"Proposes a method for underwater target tracking using optical data, which consists of color, texture, shape and dynamic properties of the environment. Here, how the dynamic properties from image sequences can be used for target tracking by autonomous underwater vehicles (AUVs) is studied. Optical flow techniques are used to derive the dynamics of the images. The objects of interest are extracted from the images by using the dynamical properties and their optical features. The consecutive dynamic behavior of objects of interest is estimated based on the current dynamics. Using the predicted dynamics, the region of interest (ROI) in the image can be identified reducing the amount of data to be processed. This increases the speed of processing using the hardware available in small pressure hulls. Image dynamics and feature position information fused with other on-board sensor information, the navigational commands for the AUV are derived. In the paper, the extraction of objects of interest from the images based on dynamic vision is presented and the performance of this method for underwater target tracking is demonstrated by experimental results.","PeriodicalId":397110,"journal":{"name":"Proceedings of the 2000 International Symposium on Underwater Technology (Cat. No.00EX418)","volume":"463 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122358206","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}
Wavelet analysis theory is a new theory developed in recent years. It is a new time-frequency localization methods. As its analyzing precision can be changed and focused to any detail of the analyzed signal,it is very useful to study nonstationary signals. In this paper, we mainly study the wavelet theory and its application to control system. Furthermore, we use it to detect the fault of underwater vehicle's navigation angle fault, and its simulation results are given at the end of the paper.
{"title":"Wavelet transform and its application to autonomous underwater vehicle control system fault detection","authors":"Xu Dermin, G. Lei","doi":"10.1109/UT.2000.852523","DOIUrl":"https://doi.org/10.1109/UT.2000.852523","url":null,"abstract":"Wavelet analysis theory is a new theory developed in recent years. It is a new time-frequency localization methods. As its analyzing precision can be changed and focused to any detail of the analyzed signal,it is very useful to study nonstationary signals. In this paper, we mainly study the wavelet theory and its application to control system. Furthermore, we use it to detect the fault of underwater vehicle's navigation angle fault, and its simulation results are given at the end of the paper.","PeriodicalId":397110,"journal":{"name":"Proceedings of the 2000 International Symposium on Underwater Technology (Cat. No.00EX418)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123043284","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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