Pub Date : 2017-08-01DOI: 10.1109/MMAR.2017.8046871
W. Bożejko, Czeslaw Smutnicki, Mariusz Uchroński, M. Wodecki
Created in the 90s of the past century methods of constructing algorithms (metaheuristic), inspired by the no free lunch theorem of Wolpert and Macready, using specific properties of problems, do not meet present expectations of practitioners. Commonly used artificial intelligence algorithms in recent years have also proved to be ineffective in solving a large group of extremely difficult instances of various problems. In the work we present some empirical methods of exploration of solution space in optimization problems whose solutions are represented by permutations. While sampling the set of permissible solutions we designate the histogram of the frequency of occurrence of local minima and on this basis we verify the statistical hypothesis concerning the (normal) distribution of occurrence of these minima. Due to this process we can flexibly change the “radius” of the searched area. Computational experiments performed on examples of the job shop problem are promising and inspire to conduct further research in this direction.
{"title":"Big valley in scheduling problems landscape — Metaheuristics with reduced searching area","authors":"W. Bożejko, Czeslaw Smutnicki, Mariusz Uchroński, M. Wodecki","doi":"10.1109/MMAR.2017.8046871","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046871","url":null,"abstract":"Created in the 90s of the past century methods of constructing algorithms (metaheuristic), inspired by the no free lunch theorem of Wolpert and Macready, using specific properties of problems, do not meet present expectations of practitioners. Commonly used artificial intelligence algorithms in recent years have also proved to be ineffective in solving a large group of extremely difficult instances of various problems. In the work we present some empirical methods of exploration of solution space in optimization problems whose solutions are represented by permutations. While sampling the set of permissible solutions we designate the histogram of the frequency of occurrence of local minima and on this basis we verify the statistical hypothesis concerning the (normal) distribution of occurrence of these minima. Due to this process we can flexibly change the “radius” of the searched area. Computational experiments performed on examples of the job shop problem are promising and inspire to conduct further research in this direction.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126460471","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046918
A. Shchekoldin, A. D. Shevyakov, Nikolay U. Dema, S. Kolyubin
The paper describes the design of the telepresence robot controlled via the head-mounted display equipped with an inertial measurement unit (IMU). To control the robot and the camera gimbal motion independently with only 3 DOF reference, we developed algorithms based on nonlinear filtering to process IMU measurements and capture head motion patterns. The system is adaptable to different operators' behaviour and works in real-time using only natural head movements. We implement this solution for shared autonomy remotely controlled robots with an augmented reality (AR) interface, which are in a rising demand for technical drills, monitoring and maintenance applications as well as for indoor guided tours.
{"title":"Adaptive head movements tracking algorithms for AR interface controlled telepresence robot","authors":"A. Shchekoldin, A. D. Shevyakov, Nikolay U. Dema, S. Kolyubin","doi":"10.1109/MMAR.2017.8046918","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046918","url":null,"abstract":"The paper describes the design of the telepresence robot controlled via the head-mounted display equipped with an inertial measurement unit (IMU). To control the robot and the camera gimbal motion independently with only 3 DOF reference, we developed algorithms based on nonlinear filtering to process IMU measurements and capture head motion patterns. The system is adaptable to different operators' behaviour and works in real-time using only natural head movements. We implement this solution for shared autonomy remotely controlled robots with an augmented reality (AR) interface, which are in a rising demand for technical drills, monitoring and maintenance applications as well as for indoor guided tours.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129585940","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046849
K. Arminski, T. Zubowicz
The paper addresses a problem of quadrotor unmanned aerial vehicle (so-called X4-flyer or quadrocopter) utility model identification for control design purposes. To that goal the quadrotor model is assumed to be composed of two abstracted subsystems, namely a rigid body (plant) and four motors equipped with blades (actuators). The model of the former is acquired based on a well-established dynamic equations of motion while the latter is to be identified as a static relationship from laboratory experiments data. Moreover, the actuator model is to account for the on-flight battery power source voltage drop effects. The actuator parameter identification algorithm is kept in a set-membership framework. In addition a mechanism to reduce the conservativeness of the solution is proposed and applied. Numerical illustration of the results is provided.
{"title":"Robust identification of quadrocopter model for control purposes","authors":"K. Arminski, T. Zubowicz","doi":"10.1109/MMAR.2017.8046849","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046849","url":null,"abstract":"The paper addresses a problem of quadrotor unmanned aerial vehicle (so-called X4-flyer or quadrocopter) utility model identification for control design purposes. To that goal the quadrotor model is assumed to be composed of two abstracted subsystems, namely a rigid body (plant) and four motors equipped with blades (actuators). The model of the former is acquired based on a well-established dynamic equations of motion while the latter is to be identified as a static relationship from laboratory experiments data. Moreover, the actuator model is to account for the on-flight battery power source voltage drop effects. The actuator parameter identification algorithm is kept in a set-membership framework. In addition a mechanism to reduce the conservativeness of the solution is proposed and applied. Numerical illustration of the results is provided.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129456791","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046925
D. Choiński, W. Ilewicz, P. Krauze, Piotr Skupin, Zdzislaw Bielecki
The paper presents preliminary results for online measurement method of isopropanol concentration in the ultrasonic nebulization process using BW-Tek compact UV/Vis spectrophotometer. The experimental setup with nebulization vessel was constructed with a probe for on-line measurements. The tests were performed using a standard mixture of isopropanol and water with the volume isopropanol concentration in the range 19% to 83%. The results of on-line spectrophotometric method were verified using stationary spectrophotometer and a gas chromatography method. Linear calibration for the obtained data was performed and measurement uncertainties for the tested method were evaluated as confidence intervals.
{"title":"On-line spectrophotometric measurements of isopropanol concentration in process of nebulization","authors":"D. Choiński, W. Ilewicz, P. Krauze, Piotr Skupin, Zdzislaw Bielecki","doi":"10.1109/MMAR.2017.8046925","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046925","url":null,"abstract":"The paper presents preliminary results for online measurement method of isopropanol concentration in the ultrasonic nebulization process using BW-Tek compact UV/Vis spectrophotometer. The experimental setup with nebulization vessel was constructed with a probe for on-line measurements. The tests were performed using a standard mixture of isopropanol and water with the volume isopropanol concentration in the range 19% to 83%. The results of on-line spectrophotometric method were verified using stationary spectrophotometer and a gas chromatography method. Linear calibration for the obtained data was performed and measurement uncertainties for the tested method were evaluated as confidence intervals.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129524230","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046927
L. Gil, M. Radetzki
Semi-symbolic simulation is becoming popular for inclusion of parameter uncertainties in the system design analysis. For robust control system design optimization, computational methods enabling fast semi-symbolic simulations are necessary. We propose an operational computation method based on orthogonal signals that is faster than step integration methods and allows the direct evaluation of system robustness to parameter variations. In order to improve the simulation performance during design optimization, we derive a novel operational method to compute the multiplication of signal expansions. Thus, common nonlinear cost functions can be directly computed, using only signal coefficients. The evaluation of signals during the optimization is avoided by this method, which is a significant advantage compared to other known approaches for dynamic system simulation. We validate the capability of our design methodology for the improvement of system performance and robustness by optimizing a DC motor control. The obtained results show that affine arithmetic computations are well suited for robust control system design optimization in the time domain.
{"title":"Semi-symbolic operational computation for robust control system design","authors":"L. Gil, M. Radetzki","doi":"10.1109/MMAR.2017.8046927","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046927","url":null,"abstract":"Semi-symbolic simulation is becoming popular for inclusion of parameter uncertainties in the system design analysis. For robust control system design optimization, computational methods enabling fast semi-symbolic simulations are necessary. We propose an operational computation method based on orthogonal signals that is faster than step integration methods and allows the direct evaluation of system robustness to parameter variations. In order to improve the simulation performance during design optimization, we derive a novel operational method to compute the multiplication of signal expansions. Thus, common nonlinear cost functions can be directly computed, using only signal coefficients. The evaluation of signals during the optimization is avoided by this method, which is a significant advantage compared to other known approaches for dynamic system simulation. We validate the capability of our design methodology for the improvement of system performance and robustness by optimizing a DC motor control. The obtained results show that affine arithmetic computations are well suited for robust control system design optimization in the time domain.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129598455","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046965
Wojciech Giernacki, Talar Sadalla, Jarosław Gośliński, P. Kozierski, J. Coelho, S. Sladic
In this paper the synthesis of a rotational speed closed-loop control system based on a fractional-order proportional-integral (FOPI) controller is presented. In particular, it is proposed the use of the SCoMR-FOPI procedure as the controller tuning method for an unmanned aerial vehicle's propulsion unit. In this framework, both the Hermite-Biehler and Pontryagin theorems are used to predefine a stability region for the controller. Several simulations were conducted in order to try to answer the questions — is the FOPI controller good enough to be an alternative to more complex FOPID controllers? In what circumstances can it be advantageous over the ubiquitous PID? How robust this fractional-order controller is regarding the parametric uncertainty of considered propulsion unit model?
{"title":"Rotational speed control of multirotor UAV's propulsion unit based on fractional-order PI controller","authors":"Wojciech Giernacki, Talar Sadalla, Jarosław Gośliński, P. Kozierski, J. Coelho, S. Sladic","doi":"10.1109/MMAR.2017.8046965","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046965","url":null,"abstract":"In this paper the synthesis of a rotational speed closed-loop control system based on a fractional-order proportional-integral (FOPI) controller is presented. In particular, it is proposed the use of the SCoMR-FOPI procedure as the controller tuning method for an unmanned aerial vehicle's propulsion unit. In this framework, both the Hermite-Biehler and Pontryagin theorems are used to predefine a stability region for the controller. Several simulations were conducted in order to try to answer the questions — is the FOPI controller good enough to be an alternative to more complex FOPID controllers? In what circumstances can it be advantageous over the ubiquitous PID? How robust this fractional-order controller is regarding the parametric uncertainty of considered propulsion unit model?","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130836397","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046907
Seyed Mohammad Zeyb Sayyadan, M. Moniri, F. Gharib
One of the most challenging issues of granular jamming robots is both predicting and measuring the stiffness variations which are a direct function of elastic module. In this regard, in previous researches, it had demonstrated that the elastic module of robot's bulk is a fundamental function of vacuum pressure and must be acquired by experimental tests. However, there was not a unique formulation for both computing and predicting the accurate elastic module in each unique amount of vacuum pressure. Therefore, in this paper, for addressing the problem, the elastic module of jammable segments is calculated in each considered vacuum pressure and we have introduced a both simple and beneficial formulation to predict the amounts of stiffness based on variations of vacuum pressure. The proposed procedure was examined by performing an experimental test as well. On the other hand, the necessity of identifying organic material was felt due to introduction of just one organic granular material in previous researches for applying. Hence, four new organic granular materials were selected and also tested. Consequently, a usable blend of two of them was presented which was mixed of black Pepper seeds and Datura grains. This blend had a lightweight construction with high ratio of strength under external forces, therefore, it can be applied when a both high-strength and lightweight jammable structure in robotics is required.
{"title":"Stiffness variations in granular jamming robots; an experimental method","authors":"Seyed Mohammad Zeyb Sayyadan, M. Moniri, F. Gharib","doi":"10.1109/MMAR.2017.8046907","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046907","url":null,"abstract":"One of the most challenging issues of granular jamming robots is both predicting and measuring the stiffness variations which are a direct function of elastic module. In this regard, in previous researches, it had demonstrated that the elastic module of robot's bulk is a fundamental function of vacuum pressure and must be acquired by experimental tests. However, there was not a unique formulation for both computing and predicting the accurate elastic module in each unique amount of vacuum pressure. Therefore, in this paper, for addressing the problem, the elastic module of jammable segments is calculated in each considered vacuum pressure and we have introduced a both simple and beneficial formulation to predict the amounts of stiffness based on variations of vacuum pressure. The proposed procedure was examined by performing an experimental test as well. On the other hand, the necessity of identifying organic material was felt due to introduction of just one organic granular material in previous researches for applying. Hence, four new organic granular materials were selected and also tested. Consequently, a usable blend of two of them was presented which was mixed of black Pepper seeds and Datura grains. This blend had a lightweight construction with high ratio of strength under external forces, therefore, it can be applied when a both high-strength and lightweight jammable structure in robotics is required.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122398736","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046851
J. Figwer, M. I. Michalczyk, T. Glówka
In the paper a modification enabling acceleration of the rate of convergence for LMS-like on-line identification and adaptation algorithms is proposed. This is based on an artificial decaying of initial conditions in recursive identification as well as adaptation algorithms. The decaying is done using a set of the most recent measurements. Properties of the algorithms with the proposed modification are compared with non-accelerated identification and adaptation algorithms in simulations of a practical adaptive control system.
{"title":"Accelerating the rate of convergence for LMS-like on-line identification and adaptation algorithms. Part 1: Basic ideas","authors":"J. Figwer, M. I. Michalczyk, T. Glówka","doi":"10.1109/MMAR.2017.8046851","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046851","url":null,"abstract":"In the paper a modification enabling acceleration of the rate of convergence for LMS-like on-line identification and adaptation algorithms is proposed. This is based on an artificial decaying of initial conditions in recursive identification as well as adaptation algorithms. The decaying is done using a set of the most recent measurements. Properties of the algorithms with the proposed modification are compared with non-accelerated identification and adaptation algorithms in simulations of a practical adaptive control system.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121090873","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046823
Christian Thormann, A. Winkler
In the case that tactile sensor matrices are placed at the fingers of a robotic gripper, it is possible to identify objects during grasping. This feature may be useful e.g. for sorting workpieces. In this article we present an approach for object identification using tactile information. For verification a test scenario is developed where the robot should sort workpieces which are based on Lego bricks. In comparison to images of camera systems commonly used in robotics, the resolution of force images provided by tactile sensors is much lower. For that reason it may be in some case useful to increase the resolution of tactile measurement to perform some tasks of object identification successfully. It can be achieved by grasping the object on different positions and merge the measured values of the tactile sensor cells (taxeis). This article additionally includes an algorithm to improve the resolution of tactile sensors. For the verification of the proposed approach a test scenario is worked out, where the orientation of a Lego brick should be detected. For this purpose a method for identification of the different sides is developed. AII algorithms are implemented with a real robot system and experimental results are presented.
{"title":"Object identification by tactile sensors with improved sensor resolution","authors":"Christian Thormann, A. Winkler","doi":"10.1109/MMAR.2017.8046823","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046823","url":null,"abstract":"In the case that tactile sensor matrices are placed at the fingers of a robotic gripper, it is possible to identify objects during grasping. This feature may be useful e.g. for sorting workpieces. In this article we present an approach for object identification using tactile information. For verification a test scenario is developed where the robot should sort workpieces which are based on Lego bricks. In comparison to images of camera systems commonly used in robotics, the resolution of force images provided by tactile sensors is much lower. For that reason it may be in some case useful to increase the resolution of tactile measurement to perform some tasks of object identification successfully. It can be achieved by grasping the object on different positions and merge the measured values of the tactile sensor cells (taxeis). This article additionally includes an algorithm to improve the resolution of tactile sensors. For the verification of the proposed approach a test scenario is worked out, where the orientation of a Lego brick should be detected. For this purpose a method for identification of the different sides is developed. AII algorithms are implemented with a real robot system and experimental results are presented.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"200 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116402175","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046837
A. Sztandera, Katarzyna Wiechetek
In the paper a concept of nonstationary network consisted of 1st order elements is presented. Research in order to approximate the assumed frequency response using the filtering network were conducted. Learning the network was achieved by minimizing the assumed error function using genetic algorithms. Introducing time function in place of time constant reduced the duration of the transition processes.
{"title":"Learning process for nonstationary filtering network using genetic algorithms","authors":"A. Sztandera, Katarzyna Wiechetek","doi":"10.1109/MMAR.2017.8046837","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046837","url":null,"abstract":"In the paper a concept of nonstationary network consisted of 1st order elements is presented. Research in order to approximate the assumed frequency response using the filtering network were conducted. Learning the network was achieved by minimizing the assumed error function using genetic algorithms. Introducing time function in place of time constant reduced the duration of the transition processes.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"781 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116414859","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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