Pub Date : 2011-12-01DOI: 10.1109/ISCIT.2011.6092151
Jie Yang, Zhifeng Zhao, Honggang Zhang
Wireless sensor networks (WSN) is becoming large-scale. It's meaningful to gather sensor data quickly and efficiently. In this paper, we present a new approach to collect sensor data by distributed rateless coding. Rateless codes, such as Luby Transform (LT) codes have been proved possessing a very good property that receivers can decode all k original packets from arbitrary k(1+ε) encoded packets. Improved LT (iLT) codes with a new degree distribution are proposed. Each sensor packet does walks randomly, stops at a random node and selects the sensor packet of that node to exclusive-or (XOR) with an appropriate probability. The process continues until the required degree is achieved. Simulation results demonstrate that the proposed method requires less inter-communication cost to complete the encoding process. At the mean time, it also makes the data gathering much faster.
{"title":"Energy efficient data gathering based on distributed iLT coding","authors":"Jie Yang, Zhifeng Zhao, Honggang Zhang","doi":"10.1109/ISCIT.2011.6092151","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6092151","url":null,"abstract":"Wireless sensor networks (WSN) is becoming large-scale. It's meaningful to gather sensor data quickly and efficiently. In this paper, we present a new approach to collect sensor data by distributed rateless coding. Rateless codes, such as Luby Transform (LT) codes have been proved possessing a very good property that receivers can decode all k original packets from arbitrary k(1+ε) encoded packets. Improved LT (iLT) codes with a new degree distribution are proposed. Each sensor packet does walks randomly, stops at a random node and selects the sensor packet of that node to exclusive-or (XOR) with an appropriate probability. The process continues until the required degree is achieved. Simulation results demonstrate that the proposed method requires less inter-communication cost to complete the encoding process. At the mean time, it also makes the data gathering much faster.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133911795","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6089734
Xiaoliang Xue, Xiaojing Huang
Block transform orthogonal frequency division multiplexing (BT-OFDM) — a system sitting in-between two extreme data transmission schemes, i.e., the conventional OFDM system and the single-carrier system, with a balanced system performance is proposed in this paper. Through data symbol grouping and block transformation, the BT-OFDM uses reduced size inverse fast Fourier transform to take the advantages of the single-carrier system to overcome the disadvantages of the conventional OFDM system. Frequency domain representation of the BT-OFDM signal reveals that the block transformation implicitly realizes a precoding or block spreading of the transmitted data symbols. When suitable IFFT size is selected, the BT-OFDM also offers the lowest overall system complexity.
{"title":"Block transform OFDM: A robust power and bandwidth efficient system with improved frequency diversity performance","authors":"Xiaoliang Xue, Xiaojing Huang","doi":"10.1109/ISCIT.2011.6089734","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089734","url":null,"abstract":"Block transform orthogonal frequency division multiplexing (BT-OFDM) — a system sitting in-between two extreme data transmission schemes, i.e., the conventional OFDM system and the single-carrier system, with a balanced system performance is proposed in this paper. Through data symbol grouping and block transformation, the BT-OFDM uses reduced size inverse fast Fourier transform to take the advantages of the single-carrier system to overcome the disadvantages of the conventional OFDM system. Frequency domain representation of the BT-OFDM signal reveals that the block transformation implicitly realizes a precoding or block spreading of the transmitted data symbols. When suitable IFFT size is selected, the BT-OFDM also offers the lowest overall system complexity.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134058991","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6092157
Yinghua Han, Jinkuan Wang, Qiang Zhao, Jing Gao
In wireless communication environment, the time-varying channel and angular spread caused by multipath fading and the mobility of mobile degrade the performance of conventional direction of arrival (DOA) tracing algorithm. In this paper, we present a DOA tracking scheme for coherently distributed source based on support vector regression method. The mapping among the outputs of the array and the DOAs of unknown plane waves is approximated by means of a family of support vector machines. Several numerical results are provided for the validation of the proposed approach while considering a small sample set.
{"title":"An efficient DOA tracking algorithm for coherently distributed source","authors":"Yinghua Han, Jinkuan Wang, Qiang Zhao, Jing Gao","doi":"10.1109/ISCIT.2011.6092157","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6092157","url":null,"abstract":"In wireless communication environment, the time-varying channel and angular spread caused by multipath fading and the mobility of mobile degrade the performance of conventional direction of arrival (DOA) tracing algorithm. In this paper, we present a DOA tracking scheme for coherently distributed source based on support vector regression method. The mapping among the outputs of the array and the DOAs of unknown plane waves is approximated by means of a family of support vector machines. Several numerical results are provided for the validation of the proposed approach while considering a small sample set.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133289153","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6089958
Yiwei Yu, E. Dutkiewicz, Xiaojing Huang, M. Muck
In this paper, we proposed a comprehensive resource allocation scheme to achieve inter-cell interference coordination and performance enhancement for the shared relay network in LTE-Advanced systems. In the scheme, the allocation process is implemented by two steps. The global frequency planning strategies are first employed to realize the interference coordination in the multi-cell environment. Then dedicated local scheduling algorithms are applied to provide further performance enhancement for cell-edge users. As shown in the simulation results, our proposed scheme can achieve the significant performance improvement for cell-edge users while maintaining the high performance for cell-center users, and thus obtain the better performance balance in the system.
{"title":"Interference coordination and performance enhancement for shared relay networks in LTE-Advanced systems","authors":"Yiwei Yu, E. Dutkiewicz, Xiaojing Huang, M. Muck","doi":"10.1109/ISCIT.2011.6089958","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089958","url":null,"abstract":"In this paper, we proposed a comprehensive resource allocation scheme to achieve inter-cell interference coordination and performance enhancement for the shared relay network in LTE-Advanced systems. In the scheme, the allocation process is implemented by two steps. The global frequency planning strategies are first employed to realize the interference coordination in the multi-cell environment. Then dedicated local scheduling algorithms are applied to provide further performance enhancement for cell-edge users. As shown in the simulation results, our proposed scheme can achieve the significant performance improvement for cell-edge users while maintaining the high performance for cell-center users, and thus obtain the better performance balance in the system.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124881943","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6092162
Yuh-Ming Huang, Y. Liang
This paper presents a novel modification of integer arithmetic code, which performs compression and encryption at the same time. It is quite different from the randomized arithmetic code (RAC), the interval splitting arithmetic code (ISAC), and the secure arithmetic code (SAC). In security, we apply the Pseudo-Random Bit Generator (PRBG) and the Secure Hash Algorithm (SHA-256) to construct the key vector. Each bit of the key vector known to both the encoder and decoder is used to determine whether the source intervals respectively allocated to each of the different symbols are needed to be adjusted prior to encoding each new symbol. Experimental results indicate that our proposed code does not compromise the coding efficiency.
{"title":"A secure arithmetic coding algorithm based on integer implementation","authors":"Yuh-Ming Huang, Y. Liang","doi":"10.1109/ISCIT.2011.6092162","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6092162","url":null,"abstract":"This paper presents a novel modification of integer arithmetic code, which performs compression and encryption at the same time. It is quite different from the randomized arithmetic code (RAC), the interval splitting arithmetic code (ISAC), and the secure arithmetic code (SAC). In security, we apply the Pseudo-Random Bit Generator (PRBG) and the Secure Hash Algorithm (SHA-256) to construct the key vector. Each bit of the key vector known to both the encoder and decoder is used to determine whether the source intervals respectively allocated to each of the different symbols are needed to be adjusted prior to encoding each new symbol. Experimental results indicate that our proposed code does not compromise the coding efficiency.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126190557","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6092187
Sangchae Lim, Youngin Park, Eonpyo Hong, D. Har
Digital Video Broadcasting — Terrestrial for Second generation (DVB-T2) was released, for the purpose of supporting High Definition Television (HDTV) services. Although DVB-T2 leads to performance improvement by introducing state-of-the-art communication techniques, the introduction of such communication techniques has become problems in implementing the system. Multiple Physical Layer Pipe (PLP), initially introduced by DVB-T2, enable application of separate code rates and modulation orders to each PLP. However, due to non-sequentially generated Base Band (BB) frames, regardless of PLP indices, construction of T2 frames is complicated. In the present paper, we present an algorithm arranging randomly produced BB frames to build T2 frames, complying with the DVB-T2 standard. The proposed method is centered on allocating memory space to each PLP, based on configurable PLP information and storing BB frames in an external memory. In addition to such an algorithm, DVB-T2 modulator is implemented in a Field Programmable Gate Array (FPGA) device.
{"title":"Implementation of FPGA-based DVB-T2 modulator with multiple PLPs","authors":"Sangchae Lim, Youngin Park, Eonpyo Hong, D. Har","doi":"10.1109/ISCIT.2011.6092187","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6092187","url":null,"abstract":"Digital Video Broadcasting — Terrestrial for Second generation (DVB-T2) was released, for the purpose of supporting High Definition Television (HDTV) services. Although DVB-T2 leads to performance improvement by introducing state-of-the-art communication techniques, the introduction of such communication techniques has become problems in implementing the system. Multiple Physical Layer Pipe (PLP), initially introduced by DVB-T2, enable application of separate code rates and modulation orders to each PLP. However, due to non-sequentially generated Base Band (BB) frames, regardless of PLP indices, construction of T2 frames is complicated. In the present paper, we present an algorithm arranging randomly produced BB frames to build T2 frames, complying with the DVB-T2 standard. The proposed method is centered on allocating memory space to each PLP, based on configurable PLP information and storing BB frames in an external memory. In addition to such an algorithm, DVB-T2 modulator is implemented in a Field Programmable Gate Array (FPGA) device.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115011988","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6092189
Xiaozhi Gao, Weijia Lei, Xianwei Xie
In this paper, the optimal power control strategies under four different types of power constraints are derived via convex optimization to maximize the ergodic capacity of secondary system based on spectrum sharing while guaranteeing QoS of the primary system transmission. The interference from primary user to secondary system is simultaneously considered in the analysis process besides the interference from secondary user to primary system. It is shown that both the transmission power of primary user and different power constraint parameters affect the ergodic capacity of secondary system severely, furthermore, the proposed power control strategies outperform the existing schemes without considering the effects of the transmission power of primary user via the achievable capacities during the simulation results.
{"title":"Optimal power control for secondary system based on spectrum sharing","authors":"Xiaozhi Gao, Weijia Lei, Xianwei Xie","doi":"10.1109/ISCIT.2011.6092189","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6092189","url":null,"abstract":"In this paper, the optimal power control strategies under four different types of power constraints are derived via convex optimization to maximize the ergodic capacity of secondary system based on spectrum sharing while guaranteeing QoS of the primary system transmission. The interference from primary user to secondary system is simultaneously considered in the analysis process besides the interference from secondary user to primary system. It is shown that both the transmission power of primary user and different power constraint parameters affect the ergodic capacity of secondary system severely, furthermore, the proposed power control strategies outperform the existing schemes without considering the effects of the transmission power of primary user via the achievable capacities during the simulation results.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131038016","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6089967
Yu-xin Zhang, Y. Miyanaga
This paper proposes an improved dynamic time warping (DTW) algorithm with a nonlinear median filtering (NMF). Recognition accuracy of conventional DTW algorithms are less than the hidden Markov model (HMM) by same voice activity detection (VAD) and noise-reduction with running spectrum filtering (RSF) and dynamic range adjustment (DRA). For analyzing some incorrect results, unlike in conventional DTW, we do not use the minimum distance to recognize. we employ NMF and seek the median distance of the every reference word with the unknown speech waveform. All recognition accuracy of conventional DTW algorithms are improved much more by NMF. The recognition accuracy of Itakura's DTW algorithm is the best. Its recognition accuracy similar to that of the HMM approach in 10 dB and 20 dB white noise.
{"title":"An improved dynamic time warping algorithm employing nonlinear median filtering","authors":"Yu-xin Zhang, Y. Miyanaga","doi":"10.1109/ISCIT.2011.6089967","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089967","url":null,"abstract":"This paper proposes an improved dynamic time warping (DTW) algorithm with a nonlinear median filtering (NMF). Recognition accuracy of conventional DTW algorithms are less than the hidden Markov model (HMM) by same voice activity detection (VAD) and noise-reduction with running spectrum filtering (RSF) and dynamic range adjustment (DRA). For analyzing some incorrect results, unlike in conventional DTW, we do not use the minimum distance to recognize. we employ NMF and seek the median distance of the every reference word with the unknown speech waveform. All recognition accuracy of conventional DTW algorithms are improved much more by NMF. The recognition accuracy of Itakura's DTW algorithm is the best. Its recognition accuracy similar to that of the HMM approach in 10 dB and 20 dB white noise.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130124131","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6089950
B. Bhumiratana
Today, several online services are provided for free in exchange for the users private information/interaction online. It is common for these services on the internet to also act as data warehouse, gathering the usage information and all interaction of its users. The collection and dissemination of the data is governed by the service provider's privacy policy, which users must agree to prior to using the service. Once agreed to the policy, the user no longer has any say in regard to how the service provider uses the data. In this paper, we propose a model for 3 parties policy architecture that allows the consumer, the data warehouse, and a 3rd party service provider that want to use the data stored by the data warehouse to negotiate the privacy policy and the need to access the data. We propose an application architecture utilizing this policy model, and discuss how it can be used. Lastly, we discuss the dataset we perform simulation experiment on, and our findings.
{"title":"A model for privacy policy agreement in online services","authors":"B. Bhumiratana","doi":"10.1109/ISCIT.2011.6089950","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089950","url":null,"abstract":"Today, several online services are provided for free in exchange for the users private information/interaction online. It is common for these services on the internet to also act as data warehouse, gathering the usage information and all interaction of its users. The collection and dissemination of the data is governed by the service provider's privacy policy, which users must agree to prior to using the service. Once agreed to the policy, the user no longer has any say in regard to how the service provider uses the data. In this paper, we propose a model for 3 parties policy architecture that allows the consumer, the data warehouse, and a 3rd party service provider that want to use the data stored by the data warehouse to negotiate the privacy policy and the need to access the data. We propose an application architecture utilizing this policy model, and discuss how it can be used. Lastly, we discuss the dataset we perform simulation experiment on, and our findings.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125576573","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 : 2011-12-01DOI: 10.1109/ISCIT.2011.6089725
J. Ha, Jin-Up Kim, Youngho Jeong
Considering multiple radio access technologies (RATs) environment for the future wireless access networks, effective RAT discovery and selection are important tasks. They enable discovery of various RATs and let the user select appropriate RAT considering users' preferences and other parameters. The wireless network operator may also take advantage of RAT selection in order to distribute loads among two or more RATs. This paper introduces our pilot design of smart radio research platform (SRRP), on which performance of RAT discovery and selection algorithms are tested. Designing SRRP, we stressed on compliance with existing technical standard specifications, e.g. IEEE P1900.4 and 802.21, efficient RAT discovery, and reasonable RAT selection performance. In regard to RAT discovery algorithm we focused on short discovery time in order to reduce battery consumption and minimize possible quality of service (QoS) degradation. Objective of RAT selection is two folded; one is to choose a satisfactory radio connection and the other one is to maintain the connection reliably. Besides RAT discovery and selection algorithms we incorporated spectrum aggregation capability into SRRP to support user's QoS requirement by allocating an extra spectrum block to a base station (BS) where the existing spectrum block is congested.
{"title":"A design of smart radio research platform for universal access in a multi-RAT environment","authors":"J. Ha, Jin-Up Kim, Youngho Jeong","doi":"10.1109/ISCIT.2011.6089725","DOIUrl":"https://doi.org/10.1109/ISCIT.2011.6089725","url":null,"abstract":"Considering multiple radio access technologies (RATs) environment for the future wireless access networks, effective RAT discovery and selection are important tasks. They enable discovery of various RATs and let the user select appropriate RAT considering users' preferences and other parameters. The wireless network operator may also take advantage of RAT selection in order to distribute loads among two or more RATs. This paper introduces our pilot design of smart radio research platform (SRRP), on which performance of RAT discovery and selection algorithms are tested. Designing SRRP, we stressed on compliance with existing technical standard specifications, e.g. IEEE P1900.4 and 802.21, efficient RAT discovery, and reasonable RAT selection performance. In regard to RAT discovery algorithm we focused on short discovery time in order to reduce battery consumption and minimize possible quality of service (QoS) degradation. Objective of RAT selection is two folded; one is to choose a satisfactory radio connection and the other one is to maintain the connection reliably. Besides RAT discovery and selection algorithms we incorporated spectrum aggregation capability into SRRP to support user's QoS requirement by allocating an extra spectrum block to a base station (BS) where the existing spectrum block is congested.","PeriodicalId":226552,"journal":{"name":"2011 11th International Symposium on Communications & Information Technologies (ISCIT)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114352933","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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