Faster-than-Nyquist Signaling (FTNS) can improve the communication system's effectiveness without reducing its reliability. However, since FTNS introduces severe intersymbol interference (ISI), it is necessary to equalize the signal at the receiver by complex equalization methods. Soft-output truncated modified Viterbi algorithm(SOTMVA) based on the Ungerboeck observation model is an effective equalization method with the bit error rate close to the Nyquist signal. In this paper, another observation model, the orthogonal basis model (OBM), is used to filter and sample the FTN signal, and the sampled discrete signal is equalized by SOVA. The simulation results show that when the acceleration is 20% and 11.1%, the performance of the system is better than that of the SOTMVA algorithm with the same complexity.
{"title":"FTN Signaling Time-Domain Equalization based on SOVA Using the OB Model","authors":"Zhang Hao-liang, Meng Zhengke, Z. Shenghua","doi":"10.1145/3291842.3291878","DOIUrl":"https://doi.org/10.1145/3291842.3291878","url":null,"abstract":"Faster-than-Nyquist Signaling (FTNS) can improve the communication system's effectiveness without reducing its reliability. However, since FTNS introduces severe intersymbol interference (ISI), it is necessary to equalize the signal at the receiver by complex equalization methods. Soft-output truncated modified Viterbi algorithm(SOTMVA) based on the Ungerboeck observation model is an effective equalization method with the bit error rate close to the Nyquist signal. In this paper, another observation model, the orthogonal basis model (OBM), is used to filter and sample the FTN signal, and the sampled discrete signal is equalized by SOVA. The simulation results show that when the acceleration is 20% and 11.1%, the performance of the system is better than that of the SOTMVA algorithm with the same complexity.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122969730","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}
Yirou Gang, Pei Zhang, Xiaohong Huang, Tianle Yang
Segment routing (SR) leverage source routing paradigm which can be used to optimize the performance of IP or Multi-Protocol Label Switching (MPLS) network. Due to the limited operation cost and immature SR technology, it's difficult for network service providers to deploy a large-scale full SR network. So, the hybrid segment routing network which consist of segment routing domain and traditional IP nodes is preferred. In this paper, we consider throughput maximization in the hybrid segment routing network. Concretely, firstly, faced with the problem of deployment for SR nodes from traditional IP network to the hybrid segment routing network, we propose an algorithm to solve it. Then, in order to improve network performance in the hybrid network with fixed SR nodes, we construct the throughput optimization model and give the heuristic algorithm to solve it. The experiments show that our model and algorithms in the hybrid network can increase the throughput compared with that in the traditional IP network.
{"title":"Throughput Maximization Routing in the Hybrid Segment Routing Network","authors":"Yirou Gang, Pei Zhang, Xiaohong Huang, Tianle Yang","doi":"10.1145/3291842.3291914","DOIUrl":"https://doi.org/10.1145/3291842.3291914","url":null,"abstract":"Segment routing (SR) leverage source routing paradigm which can be used to optimize the performance of IP or Multi-Protocol Label Switching (MPLS) network. Due to the limited operation cost and immature SR technology, it's difficult for network service providers to deploy a large-scale full SR network. So, the hybrid segment routing network which consist of segment routing domain and traditional IP nodes is preferred. In this paper, we consider throughput maximization in the hybrid segment routing network. Concretely, firstly, faced with the problem of deployment for SR nodes from traditional IP network to the hybrid segment routing network, we propose an algorithm to solve it. Then, in order to improve network performance in the hybrid network with fixed SR nodes, we construct the throughput optimization model and give the heuristic algorithm to solve it. The experiments show that our model and algorithms in the hybrid network can increase the throughput compared with that in the traditional IP network.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124049614","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}
Liu Yingxue, Zhu Wenguang, Peng Huaide, Zhou Cheng, Lu Jun, Ding Chuang
Aiming at the security issue to fulfill the complexity of power distribution communication access network in the context of energy Internet, a power-grid information security architecture model is proposed based on multi-technology fusion. First of all, the information security requirements for the power distribution network are analyzed including multi-service security and service scenarios complexity. Secondly, the proposed information security architecture model is depicted for the intelligent distribution communication network, which is based on the analysis of the information security. Finally, the model-related three-layer security access architecture is designed for the services in the power distribution network, which is of the better characteristics to ensure the information security of the power distribution network by multi-network coordination.
{"title":"Network Power-Grid Information Security Architecture Model for Intelligent Distribution Communication Network","authors":"Liu Yingxue, Zhu Wenguang, Peng Huaide, Zhou Cheng, Lu Jun, Ding Chuang","doi":"10.1145/3291842.3291908","DOIUrl":"https://doi.org/10.1145/3291842.3291908","url":null,"abstract":"Aiming at the security issue to fulfill the complexity of power distribution communication access network in the context of energy Internet, a power-grid information security architecture model is proposed based on multi-technology fusion. First of all, the information security requirements for the power distribution network are analyzed including multi-service security and service scenarios complexity. Secondly, the proposed information security architecture model is depicted for the intelligent distribution communication network, which is based on the analysis of the information security. Finally, the model-related three-layer security access architecture is designed for the services in the power distribution network, which is of the better characteristics to ensure the information security of the power distribution network by multi-network coordination.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124052239","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}
In this paper, a new filter synthesis technology with frequency-dependent coupling (FDC) has been presented by analytical synthesis method instead of exploiting optimization method. Firstly, according to the assigned frequency-independent coupling filter topology, the initial frequency-independent coupling matrix can be synthesized to realize the desired indicators. Then, the expected FDC filter topology should be chosen and the corresponding FDC matrix form can be determined. Finally, and importantly, the obtained FDC matrix for FDC filter topology can be suitably transformed by means of scaling and rotations of coupling and capacitance matrices for realizing the frequency-independent coupling matrix that the form should be consistent with the initial one. To maintain the identical indicators, the frequency-independent coupling matrix which is transformed from the FDC matrix should be equal to the initial synthesized frequency-independent coupling matrix. Hence, the elements in coupling and capacitance matrices can be solved and FDC matrix can be eventually obtained. Above all, the FDC filter synthesis approach has been illustrated with a fifth-order filter example, and the good agreements between the different filter responses have validated the validation of the proposed synthesis method.
{"title":"Analytic Synthesis of Frequency-Dependent Coupling Filter","authors":"Zhang Tao, Huang Yong","doi":"10.1145/3291842.3291913","DOIUrl":"https://doi.org/10.1145/3291842.3291913","url":null,"abstract":"In this paper, a new filter synthesis technology with frequency-dependent coupling (FDC) has been presented by analytical synthesis method instead of exploiting optimization method. Firstly, according to the assigned frequency-independent coupling filter topology, the initial frequency-independent coupling matrix can be synthesized to realize the desired indicators. Then, the expected FDC filter topology should be chosen and the corresponding FDC matrix form can be determined. Finally, and importantly, the obtained FDC matrix for FDC filter topology can be suitably transformed by means of scaling and rotations of coupling and capacitance matrices for realizing the frequency-independent coupling matrix that the form should be consistent with the initial one. To maintain the identical indicators, the frequency-independent coupling matrix which is transformed from the FDC matrix should be equal to the initial synthesized frequency-independent coupling matrix. Hence, the elements in coupling and capacitance matrices can be solved and FDC matrix can be eventually obtained. Above all, the FDC filter synthesis approach has been illustrated with a fifth-order filter example, and the good agreements between the different filter responses have validated the validation of the proposed synthesis method.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"193 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132600376","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}
Superposition virtual channel (SVC) method can enhance spatial reusability and SVC vector changes transmission channel matrix to improve system performance. However, the study of quality of service (QoS) provisioning is still blank in SVC aided multiple-input multiple-output (MIMO) system especially when heterogeneous services are transmitted. We propose the heterogeneous QoS guaranteed (HQG) SVC method to satisfy different delay-QoS requirements of heterogeneous services as well as increase system effective capacity (EC). As EC measures the capacity meeting delay-QoS requirements, we derive EC for the investigated system under Nakagami-m fading channel. Targeting at maximizing EC and obtaining better bit error rate (BER), an optimization problem is established to obtain the optimal HQG SVC vector. In order to simplify the multi-objective problem, we make the magnitudes of EC and BER on the same order through mathematical treatment and design a weighting fitness function of these two metrics. Simulation results show that the HQG SVC method can provide not only a best EC but also a similar BER as SVC method, which indicates that the HQG SVC method can guarantee heterogeneous delay-QoS requirements.
{"title":"Design of Heterogeneous QoS Guaranteed Superposition Virtual Channel aided MIMO Systems","authors":"Xinyue Li, Xuefen Chi, Linlin Zhao","doi":"10.1145/3291842.3291918","DOIUrl":"https://doi.org/10.1145/3291842.3291918","url":null,"abstract":"Superposition virtual channel (SVC) method can enhance spatial reusability and SVC vector changes transmission channel matrix to improve system performance. However, the study of quality of service (QoS) provisioning is still blank in SVC aided multiple-input multiple-output (MIMO) system especially when heterogeneous services are transmitted. We propose the heterogeneous QoS guaranteed (HQG) SVC method to satisfy different delay-QoS requirements of heterogeneous services as well as increase system effective capacity (EC). As EC measures the capacity meeting delay-QoS requirements, we derive EC for the investigated system under Nakagami-m fading channel. Targeting at maximizing EC and obtaining better bit error rate (BER), an optimization problem is established to obtain the optimal HQG SVC vector. In order to simplify the multi-objective problem, we make the magnitudes of EC and BER on the same order through mathematical treatment and design a weighting fitness function of these two metrics. Simulation results show that the HQG SVC method can provide not only a best EC but also a similar BER as SVC method, which indicates that the HQG SVC method can guarantee heterogeneous delay-QoS requirements.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131899941","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}
Yinqiao Li, Jingtao Li, Qinglong Yang, Xing Jin, Chen Wang
In this paper, a method of measuring the noise figure of multi-beam satellite is presented. The connection between a single channel and multi-channel noise figure of multi-beam system is discussed. Derivation shows that the single channel noise figure can be used to calculate the multi-beam noise figure through the amplitude coefficient of beam forming. A simulation verified the method by a multi-beam S-parameter model. In the noise figure measurement of a twelve channels return link beam, measured data showed good agreement with theory results. The proposed method is able to make the measurement of noise figure of multi-beam system simplified, it can be widely applied to the noise figure measurement of multi-beam or phased array system.
{"title":"An Investigation on Noise Figure Measurement of Multi-Beam Satellite System","authors":"Yinqiao Li, Jingtao Li, Qinglong Yang, Xing Jin, Chen Wang","doi":"10.1145/3291842.3291885","DOIUrl":"https://doi.org/10.1145/3291842.3291885","url":null,"abstract":"In this paper, a method of measuring the noise figure of multi-beam satellite is presented. The connection between a single channel and multi-channel noise figure of multi-beam system is discussed. Derivation shows that the single channel noise figure can be used to calculate the multi-beam noise figure through the amplitude coefficient of beam forming. A simulation verified the method by a multi-beam S-parameter model. In the noise figure measurement of a twelve channels return link beam, measured data showed good agreement with theory results. The proposed method is able to make the measurement of noise figure of multi-beam system simplified, it can be widely applied to the noise figure measurement of multi-beam or phased array system.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126664453","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}
Interference alignment (IA) is a new breakthrough in interference suppression technology of multiple input multiple output (MIMO) system in recent years. This technology can obtain higher system capacity than traditional interference suppression technology. In IA, the transmitter and receiver must be designed jointly, which is normally difficult to be realized. How to improve the system performance has become the focus of researchers. In this paper, based on the traditional minimum mean square error (MMSE) iterative algorithm and maximum signal-to-interference-plus-noise ratio (Max-SINR) iterative algorithm, a symbol detection aided MMSE and Max-SINR hybrid (SDA-MMSE and Max-SINR hybrid) iterative algorithm is proposed. The simulation results show that the proposed algorithm has better performance than the traditional algorithm. Meanwhile, the proposed algorithm has the same performance compared to SDA-MMSE.
{"title":"Symbol Detection Aided MMSE and Max-SINR Hybrid Interference Alignment","authors":"G. Jia, Ying Pan, Junjun Du","doi":"10.1145/3291842.3291860","DOIUrl":"https://doi.org/10.1145/3291842.3291860","url":null,"abstract":"Interference alignment (IA) is a new breakthrough in interference suppression technology of multiple input multiple output (MIMO) system in recent years. This technology can obtain higher system capacity than traditional interference suppression technology. In IA, the transmitter and receiver must be designed jointly, which is normally difficult to be realized. How to improve the system performance has become the focus of researchers. In this paper, based on the traditional minimum mean square error (MMSE) iterative algorithm and maximum signal-to-interference-plus-noise ratio (Max-SINR) iterative algorithm, a symbol detection aided MMSE and Max-SINR hybrid (SDA-MMSE and Max-SINR hybrid) iterative algorithm is proposed. The simulation results show that the proposed algorithm has better performance than the traditional algorithm. Meanwhile, the proposed algorithm has the same performance compared to SDA-MMSE.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126236922","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}
Driven by the technology of mobile Internet of things and the wide demand of sharing economy, the development of smart locks is changing with each passing day. Current schemes rely on the open network architecture which has security vulnerabilities, privacy leaks, vulnerability to various attacks and other security risks. We propose an end-to-end succinct non-interactive offline authentication scheme based on blockchain technology(BC-SNOA). Using blockchain techniques such as anonymity, ellipticcurve cryptography, workload consensus, and privacy-preserving zero-knowledge proof, the BC-SNOA implements one-time pad to improve confidentiality, offline authentication to avoid network remote intrusions and the risk of network services interruptions. It is difficult to replicate and crack because of the in chip calculation of workloads and mathematical problems. Compared with current smart locks which extract biometric verification information and control by network services, the BC-SNOA scheme is likely to accomplish beneficial properties such as high verification performance and more secure, and also makes simple hardware implementations possible.
{"title":"Offline Authentication Scheme based on Blockchain Technology for Smart Lock","authors":"Daoqi Han, Yueming Lu, Xiaofeng Du, Jiefu Gan","doi":"10.1145/3291842.3291893","DOIUrl":"https://doi.org/10.1145/3291842.3291893","url":null,"abstract":"Driven by the technology of mobile Internet of things and the wide demand of sharing economy, the development of smart locks is changing with each passing day. Current schemes rely on the open network architecture which has security vulnerabilities, privacy leaks, vulnerability to various attacks and other security risks. We propose an end-to-end succinct non-interactive offline authentication scheme based on blockchain technology(BC-SNOA). Using blockchain techniques such as anonymity, ellipticcurve cryptography, workload consensus, and privacy-preserving zero-knowledge proof, the BC-SNOA implements one-time pad to improve confidentiality, offline authentication to avoid network remote intrusions and the risk of network services interruptions. It is difficult to replicate and crack because of the in chip calculation of workloads and mathematical problems. Compared with current smart locks which extract biometric verification information and control by network services, the BC-SNOA scheme is likely to accomplish beneficial properties such as high verification performance and more secure, and also makes simple hardware implementations possible.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128634440","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}
In cognitive radio system, a GOCA-CFAR algorithm is proposed to detect whether the multi-channel is idle and reduce the error rate of detecting the idle channel in a specified time slot. The algorithm is deduced mathematically. Compared with CA-CFAR and GO-CFAR algorithm, the simulation results show that GOCA-CFAR algorithm has the lowest error rate in detecting idle channels.
{"title":"Research on Multichannel Spectrum Detection Algorithm in Cognitive Radio System","authors":"Shichuan Wang","doi":"10.1145/3291842.3291866","DOIUrl":"https://doi.org/10.1145/3291842.3291866","url":null,"abstract":"In cognitive radio system, a GOCA-CFAR algorithm is proposed to detect whether the multi-channel is idle and reduce the error rate of detecting the idle channel in a specified time slot. The algorithm is deduced mathematically. Compared with CA-CFAR and GO-CFAR algorithm, the simulation results show that GOCA-CFAR algorithm has the lowest error rate in detecting idle channels.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127895744","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 Gaussian mixture probability hypothesis density (GMPHD) filter is an efficient and real-time method for estimating multiple target states with varying target number in clutter. However, the main drawback of this method is that the target birth intensity is known as a priori. In other words, the GMPHD filter is inapplicable to the tracking scenario with no priori spatial information on where targets can appear. To address this limitation, a measurement-labelled adaptive target birth intensity for GMPHD filter is proposed in this paper. All key equations of this proposed method are derived, and a multi-target tracking scenario is designed to demonstrate the performance of the proposed method. Simulation results suggest that the measurement-labelled method is an effective and efficient solution to target birth intensity adaptive problem.
{"title":"Gaussian Mixture PHD Filter with Measurement-labelled Adaptive Target Birth Intensity","authors":"Jihong Zheng, M. Gao, Haojie Yu","doi":"10.1145/3291842.3291891","DOIUrl":"https://doi.org/10.1145/3291842.3291891","url":null,"abstract":"The Gaussian mixture probability hypothesis density (GMPHD) filter is an efficient and real-time method for estimating multiple target states with varying target number in clutter. However, the main drawback of this method is that the target birth intensity is known as a priori. In other words, the GMPHD filter is inapplicable to the tracking scenario with no priori spatial information on where targets can appear. To address this limitation, a measurement-labelled adaptive target birth intensity for GMPHD filter is proposed in this paper. All key equations of this proposed method are derived, and a multi-target tracking scenario is designed to demonstrate the performance of the proposed method. Simulation results suggest that the measurement-labelled method is an effective and efficient solution to target birth intensity adaptive problem.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115753870","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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