The recursive least square(RLS) algorithm is a popular candidate for extracting parameters in digital pre-distortion because of its fast convergence and high accuracy. However, it suffers from instable convergence which leads to undesirable peak values on the error curve. In this paper, a piecewise RLS-based scheme for RF power amplifier digital pre-distortion is proposed. The proposed scheme divides the input signal into two categories, peak and non-peak, then by using RLS algorithm, it generates two sets of pre-distortion parameter, which are subsequently applied to peak signals and non-peak signals respectively. Simulation results show that the piecewise RLS is superior to the traditional method in terms of the stability and the adjacent channel power ratio (ACPR) improvement.
{"title":"A Piecewise RLS-Based Digital Predistortion Scheme for Power Amplifier","authors":"Zhisheng Jiang, Jingqi Wang, Wen Wu","doi":"10.1145/3291842.3291848","DOIUrl":"https://doi.org/10.1145/3291842.3291848","url":null,"abstract":"The recursive least square(RLS) algorithm is a popular candidate for extracting parameters in digital pre-distortion because of its fast convergence and high accuracy. However, it suffers from instable convergence which leads to undesirable peak values on the error curve. In this paper, a piecewise RLS-based scheme for RF power amplifier digital pre-distortion is proposed. The proposed scheme divides the input signal into two categories, peak and non-peak, then by using RLS algorithm, it generates two sets of pre-distortion parameter, which are subsequently applied to peak signals and non-peak signals respectively. Simulation results show that the piecewise RLS is superior to the traditional method in terms of the stability and the adjacent channel power ratio (ACPR) improvement.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"55 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":"122976136","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}
Reprogramming is a mechanism for software upgrade in the deployed devices. It is used to repair bugs in the running of the device or change the software function of the device according to the new requirements. Because the wireless body area network (WBAN) needs long-term operation, the software maintenance of the node is unavoidable. The traditional reprogramming technique can upgrade the nodes through the serial communications. However, for the internal node implanted in the WBAN, the serial port upgrade requires extra surgery. It is inconvenient and costly for the patients. Therefore, using the Over-The-Air approach for software upgrades is more suitable for the WBAN internal nodes situations. Due to the vulnerability caused by the openness of wireless networks, we propose a reprogrammable security scheme for WBAN internal nodes based on IEEE 802.15.6 protocol. It guarantees the safety in the reprogramming process based on the temporary key and the master key between the nodes and sinks.
{"title":"An Internal Node Reprogrammable Security Scheme Based on IEEE 802.15.6 in Wireless Body Area Networks","authors":"Wenbin Jiang, Jin Tan, William Liu","doi":"10.1145/3291842.3291862","DOIUrl":"https://doi.org/10.1145/3291842.3291862","url":null,"abstract":"Reprogramming is a mechanism for software upgrade in the deployed devices. It is used to repair bugs in the running of the device or change the software function of the device according to the new requirements. Because the wireless body area network (WBAN) needs long-term operation, the software maintenance of the node is unavoidable. The traditional reprogramming technique can upgrade the nodes through the serial communications. However, for the internal node implanted in the WBAN, the serial port upgrade requires extra surgery. It is inconvenient and costly for the patients. Therefore, using the Over-The-Air approach for software upgrades is more suitable for the WBAN internal nodes situations. Due to the vulnerability caused by the openness of wireless networks, we propose a reprogrammable security scheme for WBAN internal nodes based on IEEE 802.15.6 protocol. It guarantees the safety in the reprogramming process based on the temporary key and the master key between the nodes and sinks.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"37 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":"124869956","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}
Wireless Sensor Networks (WSNs) composed of many homogeneous sensors have attracted more attention especially with the integration of 5G networks. However, this kind of network suffers from significant latency during data transmission. Latency can be reduced by capitalizing on the Small World characteristic, in combination with the flexibility of Unmanned Aerial Vehicles (UAVs). The main work of interest of this paper is how to deploy UAVs and design UAV-assisted Small World WSNs. Firstly, we propose a region partition method based on routing hops to determine the target area for each UAV. Next, the Air-to-Ground channel model is adopted to determine the optimal altitude of UAVs, and the optimal horizontal location of UAVs formulated as a Mixed-Integer Nonlinear Programming problem which depends on the sensors distribution is put forward. Finally, an algorithm which analyzes the data transmission flow to create shortcuts between UAVs and sensor nodes is introduced.The simulation results fully validate the effectiveness and efficiency of the proposed scheme which not only reduces the data transmission delay but also attains high throughput compared with the traditional WSN. Furthermore, the optimal deployment scheme outperforms the random deployment on average.
{"title":"Optimization of Wireless Sensor Network by Applying Small World Concept with UAVs","authors":"Ruirui Zhang, Li Guo, Chao Dong","doi":"10.1145/3291842.3291875","DOIUrl":"https://doi.org/10.1145/3291842.3291875","url":null,"abstract":"Wireless Sensor Networks (WSNs) composed of many homogeneous sensors have attracted more attention especially with the integration of 5G networks. However, this kind of network suffers from significant latency during data transmission. Latency can be reduced by capitalizing on the Small World characteristic, in combination with the flexibility of Unmanned Aerial Vehicles (UAVs). The main work of interest of this paper is how to deploy UAVs and design UAV-assisted Small World WSNs. Firstly, we propose a region partition method based on routing hops to determine the target area for each UAV. Next, the Air-to-Ground channel model is adopted to determine the optimal altitude of UAVs, and the optimal horizontal location of UAVs formulated as a Mixed-Integer Nonlinear Programming problem which depends on the sensors distribution is put forward. Finally, an algorithm which analyzes the data transmission flow to create shortcuts between UAVs and sensor nodes is introduced.The simulation results fully validate the effectiveness and efficiency of the proposed scheme which not only reduces the data transmission delay but also attains high throughput compared with the traditional WSN. Furthermore, the optimal deployment scheme outperforms the random deployment on average.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"26 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":"125283482","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 basic idea of Interference Alignment consists in precoding the transmitted signals such that they are aligned at the receiver where they constitute interference, while at the same time disjointed from the desired signal. In this paper, the minimum mean square error (SDA - MMSE) algorithm and the least squares (SDA - LS) algorithm based on symbol detection are proposed on the traditional MMSE algorithm and the least squares (LS) algorithm. Firstly, the iterative calculation is carried out based on the traditional algorithm, and then the iterative calculation is carried out by using the improved algorithm. The simulation results show that the proposed algorithm has better system performance than the traditional algorithm, and the system performance of SDA-MMSE algorithm is found to be optimal.
{"title":"MMSE and LS Interference Alignment Algorithm Based on Symbol Detection","authors":"G. Jia, Han Zhang, Gaofeng Zhang","doi":"10.1145/3291842.3291865","DOIUrl":"https://doi.org/10.1145/3291842.3291865","url":null,"abstract":"The basic idea of Interference Alignment consists in precoding the transmitted signals such that they are aligned at the receiver where they constitute interference, while at the same time disjointed from the desired signal. In this paper, the minimum mean square error (SDA - MMSE) algorithm and the least squares (SDA - LS) algorithm based on symbol detection are proposed on the traditional MMSE algorithm and the least squares (LS) algorithm. Firstly, the iterative calculation is carried out based on the traditional algorithm, and then the iterative calculation is carried out by using the improved algorithm. The simulation results show that the proposed algorithm has better system performance than the traditional algorithm, and the system performance of SDA-MMSE algorithm is found to be optimal.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"109 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":"117219357","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 wireless microwave energy transmission system will excite high-frequency electromagnetic fields in the surrounding space when it works. If the electromagnetic disturbance value of the radiation is too large, it will cause electromagnetic interference to the surrounding environment, which will affect the normal operation of the equipment and system in the electromagnetic environment. In this paper, through the simulation and analysis of the electromagnetic radiation generated by the microwave energy transmission system, the electromagnetic radiation of the microwave energy transmission system to the surrounding environment is analyzed and evaluated. Based on ANSYS EMIT, the blocking interference generated by the microwave energy transmission system to the adjacent band communication system in the surrounding environment is predicted. The electromagnetic compatibility between the microwave energy transmission system and the communication system is studied.
{"title":"Electromagnetic Compatibility of Microwave Energy Transmission System and Adjacent Frequency Communication System","authors":"Yifan Zhang, Hongxin Zhang, Weiqi Chen","doi":"10.1145/3291842.3291892","DOIUrl":"https://doi.org/10.1145/3291842.3291892","url":null,"abstract":"The wireless microwave energy transmission system will excite high-frequency electromagnetic fields in the surrounding space when it works. If the electromagnetic disturbance value of the radiation is too large, it will cause electromagnetic interference to the surrounding environment, which will affect the normal operation of the equipment and system in the electromagnetic environment. In this paper, through the simulation and analysis of the electromagnetic radiation generated by the microwave energy transmission system, the electromagnetic radiation of the microwave energy transmission system to the surrounding environment is analyzed and evaluated. Based on ANSYS EMIT, the blocking interference generated by the microwave energy transmission system to the adjacent band communication system in the surrounding environment is predicted. The electromagnetic compatibility between the microwave energy transmission system and the communication system is studied.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"60 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":"128283139","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 order to enhance the accuracy and real-time performance of mobile robot in complex environment, a pedestrian detection and tracking method combined with infrared and visible image features is proposed. Firstly, a 4 degree of freedom multispectral vision platform is designed. Secondly, a coarse-fine pedestrian detection and tracking is implemented by using census transform histogram (CENTRIST) descriptor and kernel correlation filtering (KCF). Then, a head-eye coordination control strategy for multispectral vision platform is established. Finally, the accuracy of pedestrian detection and tracking algorithm as well as the effectiveness of the active visual tracking system are verified. The experimental results clearly demonstrate the effectiveness of our multispectral visual tracking system compared to that based on visible or infrared spectrum singly, and the success rate of pedestrian tracking based on multispectral images is increased by 28.9% and 10.1% respectively.
{"title":"Combined Thermal Infrared and Visible Cameras for Pedestrian Detection and Tracking","authors":"Li Wei, Lu Naiguang, Dong Mingli","doi":"10.1145/3291842.3291883","DOIUrl":"https://doi.org/10.1145/3291842.3291883","url":null,"abstract":"In order to enhance the accuracy and real-time performance of mobile robot in complex environment, a pedestrian detection and tracking method combined with infrared and visible image features is proposed. Firstly, a 4 degree of freedom multispectral vision platform is designed. Secondly, a coarse-fine pedestrian detection and tracking is implemented by using census transform histogram (CENTRIST) descriptor and kernel correlation filtering (KCF). Then, a head-eye coordination control strategy for multispectral vision platform is established. Finally, the accuracy of pedestrian detection and tracking algorithm as well as the effectiveness of the active visual tracking system are verified. The experimental results clearly demonstrate the effectiveness of our multispectral visual tracking system compared to that based on visible or infrared spectrum singly, and the success rate of pedestrian tracking based on multispectral images is increased by 28.9% and 10.1% respectively.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"66 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":"128620320","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}
Clustering algorithm in rechargeable wireless sensor network (RWSN) is critical before developing a charging strategy. To improve the charging efficiency, reduce the total charging time and energy consumption, this paper proposes an Energy Sensing Clustering Algorithm (ESCA) considering of location and residual energy information of nodes simultaneously. The concept of the hybrid center to calculate the Wireless Charging Vehicle (WCV) charging location is introduced to completes the clustering iteration with the improved k-means. The simulation results show that ESCA performs better in WCV total charging time and charging efficiency.
{"title":"An Energy Sensing Clustering Algorithm in Rechargeable Wireless Sensor Network","authors":"Fan Wu, Huang Mei, Liu Yuan-an","doi":"10.1145/3291842.3291887","DOIUrl":"https://doi.org/10.1145/3291842.3291887","url":null,"abstract":"Clustering algorithm in rechargeable wireless sensor network (RWSN) is critical before developing a charging strategy. To improve the charging efficiency, reduce the total charging time and energy consumption, this paper proposes an Energy Sensing Clustering Algorithm (ESCA) considering of location and residual energy information of nodes simultaneously. The concept of the hybrid center to calculate the Wireless Charging Vehicle (WCV) charging location is introduced to completes the clustering iteration with the improved k-means. The simulation results show that ESCA performs better in WCV total charging time and charging efficiency.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"1 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":"131139610","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}
Through the analysis of the existing load balancing algorithm, aiming at the local hot spots appearing in network traffic may cause "starvation" or overload in the processing core, this paper proposes a multi-state load balancing algorithm based on packet classification SDLBA. The algorithm uses static load balancing algorithm for non-TCP packets and dynamic load balancing algorithm for TCP packets. The static load balancing algorithm uses the traditional hash algorithm to load. The dynamic load balancing algorithm adopts the idea of a combination of a light overload table and a heavy overload table. When the light load threshold is satisfied, a new connection re-mapping strategy is adopted to meet the heavy load threshold The core connectivity migration strategy is adopted to periodically update each processing core load and light, heavy load table and other data table information so that each processing core tends to balance the load as much as possible when the flow is complete.
{"title":"Polymorphic Load Balancing Algorithm Based on Packet Classification","authors":"Dapeng Man, Wu Yang, Guoqing Tian","doi":"10.1145/3291842.3291911","DOIUrl":"https://doi.org/10.1145/3291842.3291911","url":null,"abstract":"Through the analysis of the existing load balancing algorithm, aiming at the local hot spots appearing in network traffic may cause \"starvation\" or overload in the processing core, this paper proposes a multi-state load balancing algorithm based on packet classification SDLBA. The algorithm uses static load balancing algorithm for non-TCP packets and dynamic load balancing algorithm for TCP packets. The static load balancing algorithm uses the traditional hash algorithm to load. The dynamic load balancing algorithm adopts the idea of a combination of a light overload table and a heavy overload table. When the light load threshold is satisfied, a new connection re-mapping strategy is adopted to meet the heavy load threshold The core connectivity migration strategy is adopted to periodically update each processing core load and light, heavy load table and other data table information so that each processing core tends to balance the load as much as possible when the flow is complete.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"40 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":"133289200","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}
Aiming to solve the problem of mutual restriction of sensitivity and measuring speed in traditional broadband electric field measurement, a wideband rapid electric field measurement method with high sensitivity based on optical frequency comb is proposed and the corresponding frequency recovery algorithm is designed. An electric field measurement system consisting of femtosecond lasers, an optical electric field sensor and a high speed digital acquisition card was built, tested and verified by experiments. Experiment results indicated that the sensitivity of the system is better than that of 20mV/m in the range of 1-9.5GHz, and the uncertainty of frequency recovery is within 1MHz, and single measuring time is about 2 minutes.
{"title":"Wideband Rapid Electric Field Measurement with High Sensitivity based on Optical Frequency Comb","authors":"Yakai Dong, Shuguo Xie, Yan Yang, Yuanyuan Li","doi":"10.1145/3291842.3291850","DOIUrl":"https://doi.org/10.1145/3291842.3291850","url":null,"abstract":"Aiming to solve the problem of mutual restriction of sensitivity and measuring speed in traditional broadband electric field measurement, a wideband rapid electric field measurement method with high sensitivity based on optical frequency comb is proposed and the corresponding frequency recovery algorithm is designed. An electric field measurement system consisting of femtosecond lasers, an optical electric field sensor and a high speed digital acquisition card was built, tested and verified by experiments. Experiment results indicated that the sensitivity of the system is better than that of 20mV/m in the range of 1-9.5GHz, and the uncertainty of frequency recovery is within 1MHz, and single measuring time is about 2 minutes.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"15 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":"133507226","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}
With the development of Internet and E-commerce, scalping phenomenon becomes more common and severe. Because of the giant profit, some software means such as scripts and batching-operation are utilized by the profiteers, to scalp tickets or discount coupons from retailers and sell to the buyers. So, an effective way to detect scalping on Internet is important and necessary for online retailers. In this paper, we propose a new integrated method called SADM (Scalping Anomaly Detection Method) to detect the special abnormal behavior, scalping. We collect mobile traffic data from ISPs (Internet Service Providers) and process them to the NFP data (Network Fingerprint data), which records detailed activities on mobile Internet created by users' cell phones. After that, SADM constructs the powerful feature set by the means of feature engineering consisting of feature extraction and feature selection. We combine statistic method and subspace method RPCA-ADMM (Robust PCA-Alternating Direction Method of Multipliers) for a more robust feature set. For anomaly detection models, clustering methods are used to produce the final scalping blacklist. The experiment results show that our SADM method is useful for detecting the special scalping behavior generated by malware.
{"title":"Scalping Anomaly Detection Based on Mobile Internet Traffic Data","authors":"Chuting Wu, K. Yu, Xiaofei Wu","doi":"10.1145/3291842.3291905","DOIUrl":"https://doi.org/10.1145/3291842.3291905","url":null,"abstract":"With the development of Internet and E-commerce, scalping phenomenon becomes more common and severe. Because of the giant profit, some software means such as scripts and batching-operation are utilized by the profiteers, to scalp tickets or discount coupons from retailers and sell to the buyers. So, an effective way to detect scalping on Internet is important and necessary for online retailers. In this paper, we propose a new integrated method called SADM (Scalping Anomaly Detection Method) to detect the special abnormal behavior, scalping. We collect mobile traffic data from ISPs (Internet Service Providers) and process them to the NFP data (Network Fingerprint data), which records detailed activities on mobile Internet created by users' cell phones. After that, SADM constructs the powerful feature set by the means of feature engineering consisting of feature extraction and feature selection. We combine statistic method and subspace method RPCA-ADMM (Robust PCA-Alternating Direction Method of Multipliers) for a more robust feature set. For anomaly detection models, clustering methods are used to produce the final scalping blacklist. The experiment results show that our SADM method is useful for detecting the special scalping behavior generated by malware.","PeriodicalId":283197,"journal":{"name":"Proceedings of the 2nd International Conference on Telecommunications and Communication Engineering","volume":"99 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":"134178347","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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