Pub Date : 2022-08-01DOI: 10.7763/ijmo.2022.v13.803
Roxana M. Motorga, V. Muresan, M. Abrudean
This paper is presenting a control solution for the concentration of the 13C isotope, both at the output and inside of the separation column; the proposed solutions are a relay and a PID controller. The 13C isotope results after a distributed parameter process, specifically the chemical exchange process of the carbon dioxide and carbamate. The analytical solution that was determined in order to model the described process is simulated. The evolution of the proposed solution depends on two parameters: the position in the column height and the time. The reference model is simulated in order to reach to the desired concentration using an acceptable flow of solution. The tuning method for the PID controller is Ziegler-Nichols, based on the bipositional relay. The advantage obtained during this control process consists of the possibility of reaching the desired concentration of the 13C isotope at any point of height inside the separation column.
{"title":"Control and Simulation of A 13C Isotope Separation Process","authors":"Roxana M. Motorga, V. Muresan, M. Abrudean","doi":"10.7763/ijmo.2022.v13.803","DOIUrl":"https://doi.org/10.7763/ijmo.2022.v13.803","url":null,"abstract":"This paper is presenting a control solution for the concentration of the 13C isotope, both at the output and inside of the separation column; the proposed solutions are a relay and a PID controller. The 13C isotope results after a distributed parameter process, specifically the chemical exchange process of the carbon dioxide and carbamate. The analytical solution that was determined in order to model the described process is simulated. The evolution of the proposed solution depends on two parameters: the position in the column height and the time. The reference model is simulated in order to reach to the desired concentration using an acceptable flow of solution. The tuning method for the PID controller is Ziegler-Nichols, based on the bipositional relay. The advantage obtained during this control process consists of the possibility of reaching the desired concentration of the 13C isotope at any point of height inside the separation column.","PeriodicalId":134487,"journal":{"name":"International Journal of Modeling and Optimization","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116573569","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 : 2022-08-01DOI: 10.7763/ijmo.2022.v13.807
J. Piao, Yu-Jing Wu, Yixian Xu
With the continuous development of automotive electronic technology and the maturity of system integration technology, the real-time performance and security have attracted more and more attention in automotive industries. However, identically with other in-vehicle bus protocol (e.g. CAN, LIN and MOST), their security are not considered in the origin of design. Therefore, security of FlexRay bus is directly related to human's privacy and life. In this paper, we proposed a security framework for FlexRay network. Considering the limitation of computing resources and the real-time performance of in-vehicle ECUs, we optimize the original MAC(Message Authentication) algorithm. To strength the security level and robutness of the system, we recommend to use ECC (Elliptic Curves Cryptography) encryption algorithm and dual channel model for our security framework. By using our proposed model, the bandwidth can be reduced 25% and the computational time can decrease evidently.
{"title":"A Security Framework for In-Vehicle FlexRay Bus Network","authors":"J. Piao, Yu-Jing Wu, Yixian Xu","doi":"10.7763/ijmo.2022.v13.807","DOIUrl":"https://doi.org/10.7763/ijmo.2022.v13.807","url":null,"abstract":"With the continuous development of automotive electronic technology and the maturity of system integration technology, the real-time performance and security have attracted more and more attention in automotive industries. However, identically with other in-vehicle bus protocol (e.g. CAN, LIN and MOST), their security are not considered in the origin of design. Therefore, security of FlexRay bus is directly related to human's privacy and life. In this paper, we proposed a security framework for FlexRay network. Considering the limitation of computing resources and the real-time performance of in-vehicle ECUs, we optimize the original MAC(Message Authentication) algorithm. To strength the security level and robutness of the system, we recommend to use ECC (Elliptic Curves Cryptography) encryption algorithm and dual channel model for our security framework. By using our proposed model, the bandwidth can be reduced 25% and the computational time can decrease evidently.","PeriodicalId":134487,"journal":{"name":"International Journal of Modeling and Optimization","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125838834","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 : 2022-08-01DOI: 10.7763/ijmo.2022.v13.805
I. Stefan, O. Stan, L. Miclea
The paper describes the characteristics of a new experimental automated web testing approach and component that allows the users to test functionalities of a web-based software under test (SUT) using a succession of parametrizable predefined test templates. The parametrizable templates usage supports a minimal validation of a finalized work without automated testing skills development because these are provided by default. The independent web developers without the required resources to automatically test the functionality of their applications could successfully integrate solutions based on the presented approach into their practice. The tactic allows the configuration of the test cases with the specific values required by the desired SUT characteristics through a novel graphic-based policy for the definition of test cases.
{"title":"Towards Automated Web Functional Testing Using Predefined Templates","authors":"I. Stefan, O. Stan, L. Miclea","doi":"10.7763/ijmo.2022.v13.805","DOIUrl":"https://doi.org/10.7763/ijmo.2022.v13.805","url":null,"abstract":"The paper describes the characteristics of a new experimental automated web testing approach and component that allows the users to test functionalities of a web-based software under test (SUT) using a succession of parametrizable predefined test templates. The parametrizable templates usage supports a minimal validation of a finalized work without automated testing skills development because these are provided by default. The independent web developers without the required resources to automatically test the functionality of their applications could successfully integrate solutions based on the presented approach into their practice. The tactic allows the configuration of the test cases with the specific values required by the desired SUT characteristics through a novel graphic-based policy for the definition of test cases.","PeriodicalId":134487,"journal":{"name":"International Journal of Modeling and Optimization","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131728788","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 : 2022-08-01DOI: 10.7763/ijmo.2022.v13.808
Laura Țîrle, I. Ursu, D. Enciu
The article presents a method for identifying and locating damages in an aluminum plate using Lamb waves. For this, a network of PZT wafer type actuators/sensors is used to generate and detect Lamb waves. The damage location algorithm is sketched taking into account the network configuration of PZT sensors. The experimental results confirm the calculation procedure.
{"title":"Damage Identification and Localization in an Aluminium Plate Based on Lamb Waves","authors":"Laura Țîrle, I. Ursu, D. Enciu","doi":"10.7763/ijmo.2022.v13.808","DOIUrl":"https://doi.org/10.7763/ijmo.2022.v13.808","url":null,"abstract":"The article presents a method for identifying and locating damages in an aluminum plate using Lamb waves. For this, a network of PZT wafer type actuators/sensors is used to generate and detect Lamb waves. The damage location algorithm is sketched taking into account the network configuration of PZT sensors. The experimental results confirm the calculation procedure.","PeriodicalId":134487,"journal":{"name":"International Journal of Modeling and Optimization","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131137517","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 : 2022-08-01DOI: 10.7763/ijmo.2022.v13.806
I. Clitan, V. Muresan, M. Abrudean, Andrei F. Clitan
Upon an active research regarding the influence of environmental factors on the COVID-19 infection rate, that denoted a divided opinion between a positive or negative influence in term of humidity and the SARS COV-2 virus spread, the authors were able to obtain a quantification effect of relative humidity (RH) influence on the spread of SARS COV-2 virus, in Romania, and consequently the influence of RH on the future number of daily COVID-19 positive cases. The discussed quantification was validated by means of computer software, and the aid of a mathematical model that predicts the outcome of COVID-19 disease on a horizon of 28 days, based on a complex neural network structure, trained using consistent data tracking the evolution of daily COVID-19 cases from March 2020 till October 2020, tool designed by the authors themselves. The validated quantification revealed that the maximum influence of RH on the increase of daily COVID-19 infections is between 60% - 70%, due to the temperate climate, while zero influence occurs at a RH higher than 90%.
{"title":"Influence of Humidity on the Evolution of COVID-19 Daily Cases in Romania — Data Based Study","authors":"I. Clitan, V. Muresan, M. Abrudean, Andrei F. Clitan","doi":"10.7763/ijmo.2022.v13.806","DOIUrl":"https://doi.org/10.7763/ijmo.2022.v13.806","url":null,"abstract":"Upon an active research regarding the influence of environmental factors on the COVID-19 infection rate, that denoted a divided opinion between a positive or negative influence in term of humidity and the SARS COV-2 virus spread, the authors were able to obtain a quantification effect of relative humidity (RH) influence on the spread of SARS COV-2 virus, in Romania, and consequently the influence of RH on the future number of daily COVID-19 positive cases. The discussed quantification was validated by means of computer software, and the aid of a mathematical model that predicts the outcome of COVID-19 disease on a horizon of 28 days, based on a complex neural network structure, trained using consistent data tracking the evolution of daily COVID-19 cases from March 2020 till October 2020, tool designed by the authors themselves. The validated quantification revealed that the maximum influence of RH on the increase of daily COVID-19 infections is between 60% - 70%, due to the temperate climate, while zero influence occurs at a RH higher than 90%.","PeriodicalId":134487,"journal":{"name":"International Journal of Modeling and Optimization","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117350382","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 : 2022-05-01DOI: 10.7763/ijmo.2022.v12.800
W. Chang
In this paper, an improved particle swarm optimization (PSO) with multiple subpopulations is developed for PID control system designs. The original single population needs to be divided into several subpopulations, and each subpopulation then tackles a corresponding performance index of the system. Under this proposed structure, several PID controllers can be simultaneously designed to meet different performance indexes when the algorithm is executed only one time. It is a great improvement because the general PSO algorithm with a single population can only deal with one performance index. To demonstrate the feasibility of the proposed scheme, a complicated chemical nonlinear process called the continuously stirred tank reactor (CSTR) is illustrated. Three different kinds of control operations are simulated including the step response control, set-point tracking control, and unstable equilibrium point control. For each control case five different performance indexes are assigned to guide the PID controller design combined with the nonlinear CSTR system. Simulation results will sufficiently confirm the superiority of the proposed algorithm.
{"title":"An Improved Particle Swarm Optimization with Multiple Strategies for PID Control System Design","authors":"W. Chang","doi":"10.7763/ijmo.2022.v12.800","DOIUrl":"https://doi.org/10.7763/ijmo.2022.v12.800","url":null,"abstract":"In this paper, an improved particle swarm optimization (PSO) with multiple subpopulations is developed for PID control system designs. The original single population needs to be divided into several subpopulations, and each subpopulation then tackles a corresponding performance index of the system. Under this proposed structure, several PID controllers can be simultaneously designed to meet different performance indexes when the algorithm is executed only one time. It is a great improvement because the general PSO algorithm with a single population can only deal with one performance index. To demonstrate the feasibility of the proposed scheme, a complicated chemical nonlinear process called the continuously stirred tank reactor (CSTR) is illustrated. Three different kinds of control operations are simulated including the step response control, set-point tracking control, and unstable equilibrium point control. For each control case five different performance indexes are assigned to guide the PID controller design combined with the nonlinear CSTR system. Simulation results will sufficiently confirm the superiority of the proposed algorithm.","PeriodicalId":134487,"journal":{"name":"International Journal of Modeling and Optimization","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130727326","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 : 2022-05-01DOI: 10.7763/ijmo.2022.v12.797
Jia-ming Li, Shuo Fu, Yu-Jing Wu, Yixian Xu
Automotive ethernet has the advantages of high bandwidth, low latency, and strong compatibility, which meets the needs of new energy vehicles for the development of network integration. Automotive ethernet can not only solve the problem of increased wiring harness and complicated wiring in the intelligentization of automotive electronics, but also can improve the comfort, reliability and multiple safety of the car. Although the car is connected to the smart phone, Bluetooth, Internet and other network systems to improve the driving pleasure for the driver, but it brings hacker attacks, security loopholes and other car network security problems that cannot be ignored, which seriously affects the safe driving of the car, personal privacy, and even endanger public safety. In this paper, we focus on the need for the network security of automotive ethernet, and analyses problem in encryption authentication algorithm. An improved AES-128 encryption algorithm and an improved MD5 authentication algorithm are proposed innovatively. Through the experimental simulation of CANoe.Ethernet, the improved AES-128 encryption algorithm proposed in this paper is 15% more efficient than the traditional encryption algorithm, and the improved MD5 authentication algorithm is 4 times faster than the traditional authentication algorithm. Thus, the active network security performance of automotive ethernet is further improved.
{"title":"High-Efficiency Encryption and Authentication Network Security for Automotive Ethernet","authors":"Jia-ming Li, Shuo Fu, Yu-Jing Wu, Yixian Xu","doi":"10.7763/ijmo.2022.v12.797","DOIUrl":"https://doi.org/10.7763/ijmo.2022.v12.797","url":null,"abstract":"Automotive ethernet has the advantages of high bandwidth, low latency, and strong compatibility, which meets the needs of new energy vehicles for the development of network integration. Automotive ethernet can not only solve the problem of increased wiring harness and complicated wiring in the intelligentization of automotive electronics, but also can improve the comfort, reliability and multiple safety of the car. Although the car is connected to the smart phone, Bluetooth, Internet and other network systems to improve the driving pleasure for the driver, but it brings hacker attacks, security loopholes and other car network security problems that cannot be ignored, which seriously affects the safe driving of the car, personal privacy, and even endanger public safety. In this paper, we focus on the need for the network security of automotive ethernet, and analyses problem in encryption authentication algorithm. An improved AES-128 encryption algorithm and an improved MD5 authentication algorithm are proposed innovatively. Through the experimental simulation of CANoe.Ethernet, the improved AES-128 encryption algorithm proposed in this paper is 15% more efficient than the traditional encryption algorithm, and the improved MD5 authentication algorithm is 4 times faster than the traditional authentication algorithm. Thus, the active network security performance of automotive ethernet is further improved.","PeriodicalId":134487,"journal":{"name":"International Journal of Modeling and Optimization","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128426015","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 : 2022-05-01DOI: 10.7763/ijmo.2022.v12.799
Gicu Călin Deac, C. Georgescu, Cicerone Laurentiu Popa, T. Dobrescu, Costel Emil Cotet
This paper describes authors’ research in developing collaborative virtual reality classrooms for laboratory and distance learning. The proposed platform was developed to facilitate the implementation of virtual reality labs that can be used by students, locally or by remote access from any device.
{"title":"Virtual Reality Laboratory for Distance Learning","authors":"Gicu Călin Deac, C. Georgescu, Cicerone Laurentiu Popa, T. Dobrescu, Costel Emil Cotet","doi":"10.7763/ijmo.2022.v12.799","DOIUrl":"https://doi.org/10.7763/ijmo.2022.v12.799","url":null,"abstract":"This paper describes authors’ research in developing collaborative virtual reality classrooms for laboratory and distance learning. The proposed platform was developed to facilitate the implementation of virtual reality labs that can be used by students, locally or by remote access from any device.","PeriodicalId":134487,"journal":{"name":"International Journal of Modeling and Optimization","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129823269","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 : 2022-05-01DOI: 10.7763/ijmo.2022.v12.802
Meijuan Luo, R. Ge, Xiuli Fu
The agitator is a kind of general equipment that is widely used in industrial and agricultural production. It involves many fields such as petroleum, chemical industry, rubber and coatings. All of which aim at obtaining homogeneous materials, improving the service performance of materials or accelerating the reaction. Compared with the ordinary agitator, the planetary agitator has a wider agitating range. This article introduces the structure and working method of planetary wheel agitator. The mathematical model of the movement track of a point on the mixing shovel is established, an example model of planetary stirring is designed and verified by comparison between Adams software and MATLAB software. On the basis of this, the change law of motion trajectory and coverage rate is analyzed; In addition to this, the influence of speed ratio on speed distribution is analyzed by EDEM simulation, which provides reference for subsequent design improvement.
{"title":"Structural Design and Trajectory Analysis of Planetary Wheel Stirring Device","authors":"Meijuan Luo, R. Ge, Xiuli Fu","doi":"10.7763/ijmo.2022.v12.802","DOIUrl":"https://doi.org/10.7763/ijmo.2022.v12.802","url":null,"abstract":"The agitator is a kind of general equipment that is widely used in industrial and agricultural production. It involves many fields such as petroleum, chemical industry, rubber and coatings. All of which aim at obtaining homogeneous materials, improving the service performance of materials or accelerating the reaction. Compared with the ordinary agitator, the planetary agitator has a wider agitating range. This article introduces the structure and working method of planetary wheel agitator. The mathematical model of the movement track of a point on the mixing shovel is established, an example model of planetary stirring is designed and verified by comparison between Adams software and MATLAB software. On the basis of this, the change law of motion trajectory and coverage rate is analyzed; In addition to this, the influence of speed ratio on speed distribution is analyzed by EDEM simulation, which provides reference for subsequent design improvement.","PeriodicalId":134487,"journal":{"name":"International Journal of Modeling and Optimization","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116291268","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 : 2022-05-01DOI: 10.7763/ijmo.2022.v12.801
C. Deac, Gicu Călin Deac, Radu Constantin Parpală, Cicerone Laurentiu Popa, C. Popescu
The paper presents a set of deep learning algorithms for detecting vibration anomalies in bearings using multivariate time series on datasets provided by Case Western Reserve University. The study considers a problem of multiclassification of the condition of the bearings depending on the type of defect, but also on the degree of defect, considering only punctual defects in an incipient phase. Once the data sets are correctly labeled and the algorithms are trained on this data, they can accurately predict the type and the size of defect. The model with the best results in the set is RNN - CNN (Recurrent Neural Network with Convolutions) giving an accuracy greater than 97% in all (load) cases.
本文提出了一套深度学习算法，用于使用凯斯西储大学提供的数据集上的多元时间序列检测轴承振动异常。该研究考虑了根据缺陷类型和缺陷程度对轴承状态进行多重分类的问题，仅考虑了初始阶段的准时缺陷。一旦数据集被正确地标记，并且算法在这些数据上得到训练，它们就可以准确地预测缺陷的类型和大小。其中效果最好的模型是RNN - CNN (Recurrent Neural Network with Convolutions)，在所有(负载)情况下的准确率都大于97%。
{"title":"Vibration Anomaly Detection Using Multivariate Time Series","authors":"C. Deac, Gicu Călin Deac, Radu Constantin Parpală, Cicerone Laurentiu Popa, C. Popescu","doi":"10.7763/ijmo.2022.v12.801","DOIUrl":"https://doi.org/10.7763/ijmo.2022.v12.801","url":null,"abstract":"The paper presents a set of deep learning algorithms for detecting vibration anomalies in bearings using multivariate time series on datasets provided by Case Western Reserve University. The study considers a problem of multiclassification of the condition of the bearings depending on the type of defect, but also on the degree of defect, considering only punctual defects in an incipient phase. Once the data sets are correctly labeled and the algorithms are trained on this data, they can accurately predict the type and the size of defect. The model with the best results in the set is RNN - CNN (Recurrent Neural Network with Convolutions) giving an accuracy greater than 97% in all (load) cases.","PeriodicalId":134487,"journal":{"name":"International Journal of Modeling and Optimization","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128357181","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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