Pub Date : 2015-12-28DOI: 10.1109/ICCAS.2015.7364906
Seongheon Lee, Dongjin Lee, H. Bang
Controlled Flight Into Terrain (CFIT) is reported as a major cause of today's aircraft accidents. To mitigate these accidents, Predictive Ground Collision Avoidance System (PGCAS) has been used since the mid-70s. In PGCAS algorithm, however, relatively large safety margin for the terrain searching pattern could cause some drawbacks such as nuisance alarms or unnecessary pull-up commands during a tactical terrain-following or low level terrain flight to evade enemy's air defense network. In this paper, a modified algorithm based on weighted terrain searching pattern is proposed to improve PGCAS more efficiently for the low level terrain flight. The weighted terrain searching pattern reflects the aircraft's performance and the flight path to give more reasonable safety margin to the system. The terrain elevation data lying on the exterior of the terrain searching pattern are set to give lower terrain elevation than the data on the interior. The proposed algorithm is further analyzed through simulations to evaluate its performance.
{"title":"Modified algorithm of Predictive Ground Collision Avoidance System for the low level terrain flight","authors":"Seongheon Lee, Dongjin Lee, H. Bang","doi":"10.1109/ICCAS.2015.7364906","DOIUrl":"https://doi.org/10.1109/ICCAS.2015.7364906","url":null,"abstract":"Controlled Flight Into Terrain (CFIT) is reported as a major cause of today's aircraft accidents. To mitigate these accidents, Predictive Ground Collision Avoidance System (PGCAS) has been used since the mid-70s. In PGCAS algorithm, however, relatively large safety margin for the terrain searching pattern could cause some drawbacks such as nuisance alarms or unnecessary pull-up commands during a tactical terrain-following or low level terrain flight to evade enemy's air defense network. In this paper, a modified algorithm based on weighted terrain searching pattern is proposed to improve PGCAS more efficiently for the low level terrain flight. The weighted terrain searching pattern reflects the aircraft's performance and the flight path to give more reasonable safety margin to the system. The terrain elevation data lying on the exterior of the terrain searching pattern are set to give lower terrain elevation than the data on the interior. The proposed algorithm is further analyzed through simulations to evaluate its performance.","PeriodicalId":6641,"journal":{"name":"2015 15th International Conference on Control, Automation and Systems (ICCAS)","volume":"31 1","pages":"197-200"},"PeriodicalIF":0.0,"publicationDate":"2015-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74433639","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 : 2015-12-28DOI: 10.1109/ICCAS.2015.7364587
Bokyu Kwon, Soohee Han
In this paper, we propose a new robust design of the extended Kalman filter(EKF) for nonlinear state estimation problems. In order to give the robustness to the conventional EKF, we consider the linearization error instead of neglecting the nonlinear higher order terms. The linearization errors are represented as a linear function of estimation error and is treated as model uncertainty in linear model. Additionally, we propose the systematic technique for predicting the linearization errors by using the current estimated state and one step ahead one. And, the linearized model and prediction of the linearization errors can be obtained within the Kalman filtering framework.
{"title":"A robust extended Kalman filtering for linearization errors","authors":"Bokyu Kwon, Soohee Han","doi":"10.1109/ICCAS.2015.7364587","DOIUrl":"https://doi.org/10.1109/ICCAS.2015.7364587","url":null,"abstract":"In this paper, we propose a new robust design of the extended Kalman filter(EKF) for nonlinear state estimation problems. In order to give the robustness to the conventional EKF, we consider the linearization error instead of neglecting the nonlinear higher order terms. The linearization errors are represented as a linear function of estimation error and is treated as model uncertainty in linear model. Additionally, we propose the systematic technique for predicting the linearization errors by using the current estimated state and one step ahead one. And, the linearized model and prediction of the linearization errors can be obtained within the Kalman filtering framework.","PeriodicalId":6641,"journal":{"name":"2015 15th International Conference on Control, Automation and Systems (ICCAS)","volume":"7 1","pages":"1485-1487"},"PeriodicalIF":0.0,"publicationDate":"2015-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73337424","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 : 2015-12-28DOI: 10.1109/ICCAS.2015.7364706
Chanmin Jung, Jonggu Kang, M. Jin
This paper introduces a remote maintenance technology based on VDR(Voyage Data Recorder) which is capable of diagnosing the status of navigational equipment and monitoring the navigational information from a remote place via satellite communications. Firstly we implemented the messaging library complied with Ethernet-based IEC 61162-450 standard which integrates intra-ship equipment, such as VDR, AMS(Alarm Monitoring System), and BMS(Bridge Maneuvering System) into one unified network. Secondly we developed a remote maintenance application which applies the messaging. This application performs the functions which are transferring of real-time navigation data, navigation data on specific time, system status and log, and captured images. Consequently, we secured the technology of ship remote maintenance using VDR in this paper.
{"title":"The development of remote maintenance technology based on Voyage Data Recorder","authors":"Chanmin Jung, Jonggu Kang, M. Jin","doi":"10.1109/ICCAS.2015.7364706","DOIUrl":"https://doi.org/10.1109/ICCAS.2015.7364706","url":null,"abstract":"This paper introduces a remote maintenance technology based on VDR(Voyage Data Recorder) which is capable of diagnosing the status of navigational equipment and monitoring the navigational information from a remote place via satellite communications. Firstly we implemented the messaging library complied with Ethernet-based IEC 61162-450 standard which integrates intra-ship equipment, such as VDR, AMS(Alarm Monitoring System), and BMS(Bridge Maneuvering System) into one unified network. Secondly we developed a remote maintenance application which applies the messaging. This application performs the functions which are transferring of real-time navigation data, navigation data on specific time, system status and log, and captured images. Consequently, we secured the technology of ship remote maintenance using VDR in this paper.","PeriodicalId":6641,"journal":{"name":"2015 15th International Conference on Control, Automation and Systems (ICCAS)","volume":"292 1","pages":"2053-2057"},"PeriodicalIF":0.0,"publicationDate":"2015-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74777513","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 : 2015-12-28DOI: 10.1109/ICCAS.2015.7364652
K. Tomonaga, So Wakamizu, Jun Kobayashi
Here we present experimental results of classification methods for brain activity in the imagination of direction. In anticipation of its adequate performance, we used a wireless portable electroencephalography (EEG) headset to collect EEG data from subjects in the experiments, during which the subjects imagined arrows indicating one of the four directions: up, down, right, and left. The classification methods estimated the direction that the subjects imagined on the basis of their brain wave signals measured by an electrode on the portable EEG headset. We implemented several classification methods, which basically followed those of a previous study that used a medical EEG device. The classification methods consisted of a band-pass filter, fast Fourier transformation, principal component analysis, and neural network. The experimental results showed that the neural network trained with the EEG data of all subjects achieved a 52.00% classification rate. When using the EEG data of each subject, the best classification rate was 55.00%. The results using the portable EEG headset were comparable with those of the previous study.
{"title":"Experiments on classification of electroencephalography (EEG) signals in imagination of direction using a wireless portable EEG headset","authors":"K. Tomonaga, So Wakamizu, Jun Kobayashi","doi":"10.1109/ICCAS.2015.7364652","DOIUrl":"https://doi.org/10.1109/ICCAS.2015.7364652","url":null,"abstract":"Here we present experimental results of classification methods for brain activity in the imagination of direction. In anticipation of its adequate performance, we used a wireless portable electroencephalography (EEG) headset to collect EEG data from subjects in the experiments, during which the subjects imagined arrows indicating one of the four directions: up, down, right, and left. The classification methods estimated the direction that the subjects imagined on the basis of their brain wave signals measured by an electrode on the portable EEG headset. We implemented several classification methods, which basically followed those of a previous study that used a medical EEG device. The classification methods consisted of a band-pass filter, fast Fourier transformation, principal component analysis, and neural network. The experimental results showed that the neural network trained with the EEG data of all subjects achieved a 52.00% classification rate. When using the EEG data of each subject, the best classification rate was 55.00%. The results using the portable EEG headset were comparable with those of the previous study.","PeriodicalId":6641,"journal":{"name":"2015 15th International Conference on Control, Automation and Systems (ICCAS)","volume":"45 1","pages":"1805-1810"},"PeriodicalIF":0.0,"publicationDate":"2015-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76579402","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 : 2015-12-28DOI: 10.1109/ICCAS.2015.7364934
Hee-Won Chae, Chansoo Park, Jae-Bok Song
In this study, we propose a method to extract landmarks for pose-graph SLAM using only the forward-looking monocular camera mounted in a small mobile robot. By using the sliding window approach, the region of interest is determined to triangulate the landmarks. The landmark extraction process uses multiple sets of bearing information for triangulation. As the landmark is extracted, choose the landmark which is near the navigation plane to project into the 2D landmark node. To test its accuracy, the laser rangefinder is used as a ground truth. Also the various sliding window sizes are tried for a landmark to investigate the effect of the window size on the accuracy. Using this approach as landmark extraction for the SLAM algorithm, we expect to implement monocular based metric SLAM with the graph based back-end optimization.
{"title":"Sliding window based landmark extraction for indoor 2D SLAM using forward-looking monocular camera","authors":"Hee-Won Chae, Chansoo Park, Jae-Bok Song","doi":"10.1109/ICCAS.2015.7364934","DOIUrl":"https://doi.org/10.1109/ICCAS.2015.7364934","url":null,"abstract":"In this study, we propose a method to extract landmarks for pose-graph SLAM using only the forward-looking monocular camera mounted in a small mobile robot. By using the sliding window approach, the region of interest is determined to triangulate the landmarks. The landmark extraction process uses multiple sets of bearing information for triangulation. As the landmark is extracted, choose the landmark which is near the navigation plane to project into the 2D landmark node. To test its accuracy, the laser rangefinder is used as a ground truth. Also the various sliding window sizes are tried for a landmark to investigate the effect of the window size on the accuracy. Using this approach as landmark extraction for the SLAM algorithm, we expect to implement monocular based metric SLAM with the graph based back-end optimization.","PeriodicalId":6641,"journal":{"name":"2015 15th International Conference on Control, Automation and Systems (ICCAS)","volume":"20 1","pages":"336-341"},"PeriodicalIF":0.0,"publicationDate":"2015-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84265900","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 : 2015-12-28DOI: 10.1109/ICCAS.2015.7364591
Subon Kim, D. Lee
This paper reports a method to estimate the interaction forces between the surgical robot instrument and the organ tissues. A previous estimation method uses the kinematical relationship of the surgical robot instrument to estimate the interaction force at the distant tip. It is experimentally found that there is non-ignorable estimation error due to some torque loss and the friction forces inside the instrument attributes to the torque loss. In this paper, a friction model is developed to more accurately estimate the interaction force considering the structure of the instrument. The friction model also reflects the effects of the tendon-driven mechanism inside the instrument on the estimation error. Experimental result shows that the estimation error can be reduced approximately 80% in single degree of freedom free motion compared to when the friction force model was not used.
{"title":"Friction-model-based estimation of interaction force of a surgical robot","authors":"Subon Kim, D. Lee","doi":"10.1109/ICCAS.2015.7364591","DOIUrl":"https://doi.org/10.1109/ICCAS.2015.7364591","url":null,"abstract":"This paper reports a method to estimate the interaction forces between the surgical robot instrument and the organ tissues. A previous estimation method uses the kinematical relationship of the surgical robot instrument to estimate the interaction force at the distant tip. It is experimentally found that there is non-ignorable estimation error due to some torque loss and the friction forces inside the instrument attributes to the torque loss. In this paper, a friction model is developed to more accurately estimate the interaction force considering the structure of the instrument. The friction model also reflects the effects of the tendon-driven mechanism inside the instrument on the estimation error. Experimental result shows that the estimation error can be reduced approximately 80% in single degree of freedom free motion compared to when the friction force model was not used.","PeriodicalId":6641,"journal":{"name":"2015 15th International Conference on Control, Automation and Systems (ICCAS)","volume":"34 1","pages":"1503-1507"},"PeriodicalIF":0.0,"publicationDate":"2015-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85407000","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 : 2015-12-28DOI: 10.1109/ICCAS.2015.7364736
S. Khan, Muhammad Fahad Zeb, Nouman Ghafoor, Saad Jamshed, M. R. Afzal, Amre Eizad
The people with disabled lower limbs find it difficult to lead an independent life and the lack of upper body exercise may lead to disuse ailment. Various studies have shown that both children and adults benefit substantially from access to a means of independent mobility. Independent mobility is a dream for every person with some or the other physical disability especially in the case of paraplegics. In the research presented in this paper, an assistance platform was developed to help the paraplegic and elderly people by providing the ability to stand-up and move about. Virtual prototype technology was used to make the design and development of the robot more efficient using Solid-works™. The device developed may be used for rehabilitation of people recovering from extended periods of limb disuse and for paraplegic patients. Although some commercialized training machines and some developed lower-limb rehabilitation robots can perform adequate motion functions during lower limb training programs but the weight, size and cost of these devices limits their possibilities of use. In contrast, the proposed design has the potential to be used among the middle socio-economic class as a product in daily household works of the paraplegic patients.
{"title":"Design of an assistance robot for patients suffering from Paraplegia","authors":"S. Khan, Muhammad Fahad Zeb, Nouman Ghafoor, Saad Jamshed, M. R. Afzal, Amre Eizad","doi":"10.1109/ICCAS.2015.7364736","DOIUrl":"https://doi.org/10.1109/ICCAS.2015.7364736","url":null,"abstract":"The people with disabled lower limbs find it difficult to lead an independent life and the lack of upper body exercise may lead to disuse ailment. Various studies have shown that both children and adults benefit substantially from access to a means of independent mobility. Independent mobility is a dream for every person with some or the other physical disability especially in the case of paraplegics. In the research presented in this paper, an assistance platform was developed to help the paraplegic and elderly people by providing the ability to stand-up and move about. Virtual prototype technology was used to make the design and development of the robot more efficient using Solid-works™. The device developed may be used for rehabilitation of people recovering from extended periods of limb disuse and for paraplegic patients. Although some commercialized training machines and some developed lower-limb rehabilitation robots can perform adequate motion functions during lower limb training programs but the weight, size and cost of these devices limits their possibilities of use. In contrast, the proposed design has the potential to be used among the middle socio-economic class as a product in daily household works of the paraplegic patients.","PeriodicalId":6641,"journal":{"name":"2015 15th International Conference on Control, Automation and Systems (ICCAS)","volume":"22 1","pages":"830-834"},"PeriodicalIF":0.0,"publicationDate":"2015-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72816740","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 : 2015-12-28DOI: 10.1109/ICCAS.2015.7364861
Huu Toan Duong, Y. Suh
This paper proposes a simple smoother algorithm for inertial sensor-based motion tracking. It is assumed that the motion consists of moving and non-moving intervals such as golf swing, which consists of not-moving (before swing), moving (swing), not-moving (after swing) intervals. A computationally efficient suboptimal smoothing algorithm is proposed. The proposed algorithm can be used in the application with limited computational power like in a smartphone application. Through a simulation the proposed algorithm is verified.
{"title":"A computationally efficient suboptimal smoother for attitude and position estimation using inertial sensors","authors":"Huu Toan Duong, Y. Suh","doi":"10.1109/ICCAS.2015.7364861","DOIUrl":"https://doi.org/10.1109/ICCAS.2015.7364861","url":null,"abstract":"This paper proposes a simple smoother algorithm for inertial sensor-based motion tracking. It is assumed that the motion consists of moving and non-moving intervals such as golf swing, which consists of not-moving (before swing), moving (swing), not-moving (after swing) intervals. A computationally efficient suboptimal smoothing algorithm is proposed. The proposed algorithm can be used in the application with limited computational power like in a smartphone application. Through a simulation the proposed algorithm is verified.","PeriodicalId":6641,"journal":{"name":"2015 15th International Conference on Control, Automation and Systems (ICCAS)","volume":"28 1","pages":"1410-1412"},"PeriodicalIF":0.0,"publicationDate":"2015-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87793971","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 : 2015-12-28DOI: 10.1109/ICCAS.2015.7364930
V. Mishra, N. K. Tomar, M. Gupta
In this paper, a decomposition of system matrices of linear time invariant rectangular descriptor systems is proposed. Using the decomposition, a technique is developed to check the impulse controllability for rectangular descriptor systems. Necessary and sufficient conditions are stated and proved to design a proportional plus derivative feedback such that the closed loop system is free of impulse. Examples are given to illustrate the presented theory.
{"title":"Impulse controllability and impulse elimination in rectangular descriptor systems","authors":"V. Mishra, N. K. Tomar, M. Gupta","doi":"10.1109/ICCAS.2015.7364930","DOIUrl":"https://doi.org/10.1109/ICCAS.2015.7364930","url":null,"abstract":"In this paper, a decomposition of system matrices of linear time invariant rectangular descriptor systems is proposed. Using the decomposition, a technique is developed to check the impulse controllability for rectangular descriptor systems. Necessary and sufficient conditions are stated and proved to design a proportional plus derivative feedback such that the closed loop system is free of impulse. Examples are given to illustrate the presented theory.","PeriodicalId":6641,"journal":{"name":"2015 15th International Conference on Control, Automation and Systems (ICCAS)","volume":"2016 1","pages":"316-320"},"PeriodicalIF":0.0,"publicationDate":"2015-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87951229","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 : 2015-12-28DOI: 10.1109/ICCAS.2015.7364616
S. Turkay, H. Akçay
In this paper, spectral models of road profiles using nonparametric and subspace identification methods are developed from road elevation measurements. First, power spectra of road profiles are estimated on uniform grids of frequencies by averaging and windowing from road measurements. These results are illustrated on the data sets obtained from the University of Michigan Transportation Research Institute archives by computing Welch spectrum estimates for left and right vehicle tracks. Then, curve fitting by the single and two-slope approximations are applied on the Welch estimates. Rational approximations, by considering a recent subspace algorithm, the regularized nuclear norm and the regularized and reweighted nuclear norm heuristics are performed for a further shaping of power spectrum estimates. Preliminary results show that the regularized and reweighted nuclear norm heuristic algorithm yields best fits to the data by low order rational spectra without distorting too much the homogeneous road assumption. Finally, for comparision of the roughness evaluation the IRI roughness index is calculated for different algorithms assuming that road excitations are zero-mean Gaussian processes.
{"title":"Road profile modeling by subspace identification methods","authors":"S. Turkay, H. Akçay","doi":"10.1109/ICCAS.2015.7364616","DOIUrl":"https://doi.org/10.1109/ICCAS.2015.7364616","url":null,"abstract":"In this paper, spectral models of road profiles using nonparametric and subspace identification methods are developed from road elevation measurements. First, power spectra of road profiles are estimated on uniform grids of frequencies by averaging and windowing from road measurements. These results are illustrated on the data sets obtained from the University of Michigan Transportation Research Institute archives by computing Welch spectrum estimates for left and right vehicle tracks. Then, curve fitting by the single and two-slope approximations are applied on the Welch estimates. Rational approximations, by considering a recent subspace algorithm, the regularized nuclear norm and the regularized and reweighted nuclear norm heuristics are performed for a further shaping of power spectrum estimates. Preliminary results show that the regularized and reweighted nuclear norm heuristic algorithm yields best fits to the data by low order rational spectra without distorting too much the homogeneous road assumption. Finally, for comparision of the roughness evaluation the IRI roughness index is calculated for different algorithms assuming that road excitations are zero-mean Gaussian processes.","PeriodicalId":6641,"journal":{"name":"2015 15th International Conference on Control, Automation and Systems (ICCAS)","volume":"8 1","pages":"1618-1623"},"PeriodicalIF":0.0,"publicationDate":"2015-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87994714","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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