Deqing Wang, Youfeng Zhang, Xiaoyi Hu, Rong-xin Zhang, W. Su, Yongjun Xie
Cognitive acoustic (CA) is emerging as a promising technique for spectrum-efficient Underwater Acoustic Networks (UANs). Due to the unique features of UANs, especially the long propagation delay, the busy terminal problem and large interference range, traditional spectrum decision methods used for radio networks need an overhaul to work efficiently in underwater environment. In this paper, we propose a dynamic spectrum decision algorithm called Receiver-viewed Dynamic Borrowing (RvDB) algorithm for Underwater Cognitive Acoustic Networks (UCANs) to improve the efficiency of spectrum utilization. RvDB algorithm is with the following features. Firstly, the spectrum resource is decided by receiver. Secondly, the receivers can borrow the idle spectrum resource from neighbouring nodes dynamically. Finally, the spectrum sensing is completed by control packets on control channel which is separated from data channels. Simulation results show that RvDB algorithm can greatly improve the performance on spectrum efficiency.
{"title":"A dynamic spectrum decision algorithm for underwater cognitive acoustic networks","authors":"Deqing Wang, Youfeng Zhang, Xiaoyi Hu, Rong-xin Zhang, W. Su, Yongjun Xie","doi":"10.1145/2999504.3001066","DOIUrl":"https://doi.org/10.1145/2999504.3001066","url":null,"abstract":"Cognitive acoustic (CA) is emerging as a promising technique for spectrum-efficient Underwater Acoustic Networks (UANs). Due to the unique features of UANs, especially the long propagation delay, the busy terminal problem and large interference range, traditional spectrum decision methods used for radio networks need an overhaul to work efficiently in underwater environment. In this paper, we propose a dynamic spectrum decision algorithm called Receiver-viewed Dynamic Borrowing (RvDB) algorithm for Underwater Cognitive Acoustic Networks (UCANs) to improve the efficiency of spectrum utilization. RvDB algorithm is with the following features. Firstly, the spectrum resource is decided by receiver. Secondly, the receivers can borrow the idle spectrum resource from neighbouring nodes dynamically. Finally, the spectrum sensing is completed by control packets on control channel which is separated from data channels. Simulation results show that RvDB algorithm can greatly improve the performance on spectrum efficiency.","PeriodicalId":378624,"journal":{"name":"Proceedings of the 11th International Conference on Underwater Networks & Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116384549","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}
Juntao Yu, Yuan-xin Xu, Yifan Gu, Rui Yu, Tongchen Wang
With the rapid development of mobile platforms such as that of the autonomous underwater vehicle (AUV) applied in various areas such as marine information acquisition, and subsea networking, an urgent need exists for robust communication for AUV-state-monitoring, AUV real-time control, and other areas of development. We expect to establish a robust mobile underwater acoustic communication system and are particularly concerned with severe Doppler effect and multipath propagation. The hyperbolic frequency modulated (HFM) signal is used to estimate Doppler scale and achieve timing synchronization. As for the multipath propagation effect, HFM spread-spectrum modulation (HFM-SS) improves communication performance. An experiment of mobile communication was conducted in a lake, and the lake experiment has demonstrated the effectiveness of the HFM strategy, in which AUV played a role as a mobile node.
{"title":"Mobile underwater acoustic communication based on hyperbolic frequency modulation signal","authors":"Juntao Yu, Yuan-xin Xu, Yifan Gu, Rui Yu, Tongchen Wang","doi":"10.1145/2999504.3001098","DOIUrl":"https://doi.org/10.1145/2999504.3001098","url":null,"abstract":"With the rapid development of mobile platforms such as that of the autonomous underwater vehicle (AUV) applied in various areas such as marine information acquisition, and subsea networking, an urgent need exists for robust communication for AUV-state-monitoring, AUV real-time control, and other areas of development. We expect to establish a robust mobile underwater acoustic communication system and are particularly concerned with severe Doppler effect and multipath propagation. The hyperbolic frequency modulated (HFM) signal is used to estimate Doppler scale and achieve timing synchronization. As for the multipath propagation effect, HFM spread-spectrum modulation (HFM-SS) improves communication performance. An experiment of mobile communication was conducted in a lake, and the lake experiment has demonstrated the effectiveness of the HFM strategy, in which AUV played a role as a mobile node.","PeriodicalId":378624,"journal":{"name":"Proceedings of the 11th International Conference on Underwater Networks & Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125906626","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}
Underwater Acoustic Sensor Networks (UWASNs) have the wide of applications with the proliferation of the increasing underwater activities recently. Most of current studies are focused on designing protocols to improve the network performance of WASNs. However, the security of UWASNs is also an important concern since malicious nodes can easily wiretap the information transmitted in UWASNs due to the vulnerability of UWASNs. In this paper, we investigate one of security problems in UWASNs - eavesdropping behaviours. In particular, we propose a general model to quantitatively evaluate the probability of eavesdropping behaviour in UWASNs. Simulation results also validate the accuracy of our proposed model.
{"title":"On analyzing eavesdropping behaviours in underwater acoustic sensor networks","authors":"Hongning Dai, Hao Wang, Hong Xiao, Zibin Zheng, Qiu Wang, Xuran Li, Xu Zhuge","doi":"10.1145/2999504.3001100","DOIUrl":"https://doi.org/10.1145/2999504.3001100","url":null,"abstract":"Underwater Acoustic Sensor Networks (UWASNs) have the wide of applications with the proliferation of the increasing underwater activities recently. Most of current studies are focused on designing protocols to improve the network performance of WASNs. However, the security of UWASNs is also an important concern since malicious nodes can easily wiretap the information transmitted in UWASNs due to the vulnerability of UWASNs. In this paper, we investigate one of security problems in UWASNs - eavesdropping behaviours. In particular, we propose a general model to quantitatively evaluate the probability of eavesdropping behaviour in UWASNs. Simulation results also validate the accuracy of our proposed model.","PeriodicalId":378624,"journal":{"name":"Proceedings of the 11th International Conference on Underwater Networks & Systems","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128978157","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}
Orthogonal frequency-division multiplexing (OFDM) technique has become a popular choice for underwater acoustic (UA) networks recently. Impulsive noise is one of the factors that limit the performance of this technique, and the mitigation of impulsive noise receives increasing attention in the UA communication community. In this paper, a pilot-based algorithm is proposed to mitigate the impact of impulsive noise. The proposed algorithm introduces a special OFDM block as preamble during which impulsive noise mitigation is performed using the null subcarriers and then the channel response is estimated using pilot subcarriers. By assuming that the channel is quasi-stationary, the proposed algorithm adopts the channel estimation result of the previous block to estimate and mitigate the impulsive noise of the current block. We apply the proposed algorithm to process the data collected during the experiment conducted in December 2015, in the estuary of the Swan River, Western Australia. The results show that the proposed approach is able to mitigate the impulsive noise for UA OFDM systems.
{"title":"Pilot-subcarrier based impulsive noise mitigation for underwater acoustic OFDM systems","authors":"Peng Chen, Y. Rong, S. Nordholm","doi":"10.1145/2999504.3001106","DOIUrl":"https://doi.org/10.1145/2999504.3001106","url":null,"abstract":"Orthogonal frequency-division multiplexing (OFDM) technique has become a popular choice for underwater acoustic (UA) networks recently. Impulsive noise is one of the factors that limit the performance of this technique, and the mitigation of impulsive noise receives increasing attention in the UA communication community. In this paper, a pilot-based algorithm is proposed to mitigate the impact of impulsive noise. The proposed algorithm introduces a special OFDM block as preamble during which impulsive noise mitigation is performed using the null subcarriers and then the channel response is estimated using pilot subcarriers. By assuming that the channel is quasi-stationary, the proposed algorithm adopts the channel estimation result of the previous block to estimate and mitigate the impulsive noise of the current block. We apply the proposed algorithm to process the data collected during the experiment conducted in December 2015, in the estuary of the Swan River, Western Australia. The results show that the proposed approach is able to mitigate the impulsive noise for UA OFDM systems.","PeriodicalId":378624,"journal":{"name":"Proceedings of the 11th International Conference on Underwater Networks & Systems","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116858352","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 rapidly increasing of different types of mobile platform in various marine missions, tremendous Doppler effects of mobile acoustic communication pose extreme difficulty for design of mobile acoustic communication receiver. To overcome this problem, the approach of resampling has been extensively used to address the scaling effect caused by Doppler. However, computational complexity as well as the high precision sampling rate conversion needed by accurately resampling, especially for multichannel systems, leads to additional overhead of the receiver. To facilitate no resampling Doppler correction, this paper adopts a time reversal mobile acoustic communication receiver employing a two-stage Doppler correction approach, which firstly performs bulk Doppler shift estimation as well as the initial channel estimation, and then addresses the Doppler distortion by periodic channel estimation based time reversal processor, that followed by a single channel adaptive decision feedback equalizer (DFE) to tackle the residual Doppler. Sea trial experiments carried out on moving platform associated with a Doppler of -16Hz are carried out to demonstrate the effectiveness of the proposed low complexity acoustic communication approach for mobile platform.
{"title":"Time reversal acoustic communication of mobile platform using doppler correction without resampling","authors":"Weihua Jiang, F. Tong, Dongsheng Chen","doi":"10.1145/2999504.3001116","DOIUrl":"https://doi.org/10.1145/2999504.3001116","url":null,"abstract":"With the rapidly increasing of different types of mobile platform in various marine missions, tremendous Doppler effects of mobile acoustic communication pose extreme difficulty for design of mobile acoustic communication receiver. To overcome this problem, the approach of resampling has been extensively used to address the scaling effect caused by Doppler. However, computational complexity as well as the high precision sampling rate conversion needed by accurately resampling, especially for multichannel systems, leads to additional overhead of the receiver. To facilitate no resampling Doppler correction, this paper adopts a time reversal mobile acoustic communication receiver employing a two-stage Doppler correction approach, which firstly performs bulk Doppler shift estimation as well as the initial channel estimation, and then addresses the Doppler distortion by periodic channel estimation based time reversal processor, that followed by a single channel adaptive decision feedback equalizer (DFE) to tackle the residual Doppler. Sea trial experiments carried out on moving platform associated with a Doppler of -16Hz are carried out to demonstrate the effectiveness of the proposed low complexity acoustic communication approach for mobile platform.","PeriodicalId":378624,"journal":{"name":"Proceedings of the 11th International Conference on Underwater Networks & Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129238234","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 cognitive access techniques were originally developed for radio communication networks, and are recently extended to the research area for underwater acoustic networks. One of the important problems for developing the underwater cognitive acoustic networks lies in the optimal spectrum sensing strategy to maximize the exploitation of spectrum holes, which are the idle channels due to the absence of the primary acoustic user. To overcome this challenge, we propose the media access control (MAC)-layer spectrum sensing scheme to find the spectrum hole with minimum channel switching delay while obtaining the maximum signal-to-noise ratio. Using our proposed MAC-layer spectrum sensing scheme, the secondary underwater acoustic users efficiently reduce the channel switching delay.
{"title":"Efficient MAC-layer spectrum sensing scheme over underwater cognitive acoustic networks","authors":"Xi Zhang, Qixuan Zhu, Jingqing Wang","doi":"10.1145/2999504.3001089","DOIUrl":"https://doi.org/10.1145/2999504.3001089","url":null,"abstract":"The cognitive access techniques were originally developed for radio communication networks, and are recently extended to the research area for underwater acoustic networks. One of the important problems for developing the underwater cognitive acoustic networks lies in the optimal spectrum sensing strategy to maximize the exploitation of spectrum holes, which are the idle channels due to the absence of the primary acoustic user. To overcome this challenge, we propose the media access control (MAC)-layer spectrum sensing scheme to find the spectrum hole with minimum channel switching delay while obtaining the maximum signal-to-noise ratio. Using our proposed MAC-layer spectrum sensing scheme, the secondary underwater acoustic users efficiently reduce the channel switching delay.","PeriodicalId":378624,"journal":{"name":"Proceedings of the 11th International Conference on Underwater Networks & Systems","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121918968","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}
Zhenfeng Jiang, Yanming Ma, Jiali Chen, Zigeng Wang, Zheng Peng, Jun Liu, Guitao Han
The Earth is a water planet. The ocean is used for nature resource exploitation, fishery, etc., and it also plays critical roles in global climate regulation and transportation. Consequently, it is extremely important to keep track of its condition. And thus ocean observation systems have received increasing attentions.
{"title":"Towards multi-functional light-weight long-term real-time coastal ocean observation system","authors":"Zhenfeng Jiang, Yanming Ma, Jiali Chen, Zigeng Wang, Zheng Peng, Jun Liu, Guitao Han","doi":"10.1145/2999504.3001117","DOIUrl":"https://doi.org/10.1145/2999504.3001117","url":null,"abstract":"The Earth is a water planet. The ocean is used for nature resource exploitation, fishery, etc., and it also plays critical roles in global climate regulation and transportation. Consequently, it is extremely important to keep track of its condition. And thus ocean observation systems have received increasing attentions.","PeriodicalId":378624,"journal":{"name":"Proceedings of the 11th International Conference on Underwater Networks & Systems","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122165642","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}
Miaomiao Liu, Fei Ji, Q. Guan, Hua Yu, Fangjiong Chen, G. Wei
The harsh environment in the water has imposed challenges for underwater sensor networks (USNs), which collect the sensed data from the underwater sensors to the sink on land. The time-varying underwater acoustic channel has low band-width and high bit error rate, which leads to low data collection efficiency. Furthermore, the heterogeneous model of USNs that uses acoustic communications under the water and wireless communication above the water makes it difficult in efficient routing and forwarding for data collection. To this end, we propose a novel on-surface wireless-assisted opportunistic routing (SurOpp) for USNs. SurOpp deploys multiple buoy nodes on surface and includes all of them in the forwarding candidates to form a receive diversity. The opportunities of reception and forwarding in buoy nodes are exploited to improve the end-to-end transmissions. SurOpp also adopts rateless codes in the source to achieve opportunistic reception in the sink. The cooperation of both opportunistic reception in the buoys and the sink further decreases the messages of control overhead. The wireless interface in the buoy undertakes all the message exchanges in forwarding coordination to compensate the bandwidth limit of the acoustic channel. Simulations in NS3 show that SurOpp outperforms the traditional routing and existing opportunistic routing in terms of packet delivery ratio, end-to-end delay and energy consumption.
{"title":"On-surface wireless-assisted opportunistic routing for underwater sensor networks","authors":"Miaomiao Liu, Fei Ji, Q. Guan, Hua Yu, Fangjiong Chen, G. Wei","doi":"10.1145/2999504.3001102","DOIUrl":"https://doi.org/10.1145/2999504.3001102","url":null,"abstract":"The harsh environment in the water has imposed challenges for underwater sensor networks (USNs), which collect the sensed data from the underwater sensors to the sink on land. The time-varying underwater acoustic channel has low band-width and high bit error rate, which leads to low data collection efficiency. Furthermore, the heterogeneous model of USNs that uses acoustic communications under the water and wireless communication above the water makes it difficult in efficient routing and forwarding for data collection. To this end, we propose a novel on-surface wireless-assisted opportunistic routing (SurOpp) for USNs. SurOpp deploys multiple buoy nodes on surface and includes all of them in the forwarding candidates to form a receive diversity. The opportunities of reception and forwarding in buoy nodes are exploited to improve the end-to-end transmissions. SurOpp also adopts rateless codes in the source to achieve opportunistic reception in the sink. The cooperation of both opportunistic reception in the buoys and the sink further decreases the messages of control overhead. The wireless interface in the buoy undertakes all the message exchanges in forwarding coordination to compensate the bandwidth limit of the acoustic channel. Simulations in NS3 show that SurOpp outperforms the traditional routing and existing opportunistic routing in terms of packet delivery ratio, end-to-end delay and energy consumption.","PeriodicalId":378624,"journal":{"name":"Proceedings of the 11th International Conference on Underwater Networks & Systems","volume":"202 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123043310","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, we investigate the degrees of freedom (DoF) of a layered 2 × 3 × 3 X channel for underwater acoustic networks (UANs), where each of the two source nodes sends an independent message to each of the three destination nodes via the relay layer with three nodes. The key problem is to maximize the achievable DoF with proper interference management. Using the long propagation delay property of UANs, we propose a feasible scheme based on distance-aligned structure (DAS), which achieves the DoF upper bound of 3/2. The core idea is to obtain six decodable message symbols over four time slots by proper transceiver design with an aligned interference neutralization approach.
{"title":"DoF-achieving distance-aligned structure for layered underwater acoustic 2x3x3 X networks","authors":"Zhijie Bao, Feng Liu, Shengming Jiang, Shuchao Jiang","doi":"10.1145/2999504.3001088","DOIUrl":"https://doi.org/10.1145/2999504.3001088","url":null,"abstract":"In this paper, we investigate the degrees of freedom (DoF) of a layered 2 × 3 × 3 X channel for underwater acoustic networks (UANs), where each of the two source nodes sends an independent message to each of the three destination nodes via the relay layer with three nodes. The key problem is to maximize the achievable DoF with proper interference management. Using the long propagation delay property of UANs, we propose a feasible scheme based on distance-aligned structure (DAS), which achieves the DoF upper bound of 3/2. The core idea is to obtain six decodable message symbols over four time slots by proper transceiver design with an aligned interference neutralization approach.","PeriodicalId":378624,"journal":{"name":"Proceedings of the 11th International Conference on Underwater Networks & Systems","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128708296","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}
Currently, the coastal communication is mainly provided by satellite networks, which are expensive with low transmission rate and unable to support underwater communication efficiently. In this work, we propose a communication architecture for coastal network based on long term evolution (LTE) cellular networks in which a cellular network architecture is designed for the maritime communication scenario. Some key technologies of next-generation cellular networks such as device-to-device (D2D) and multiple input multiple output (MIMO) are integrated into the proposed architecture to support more efficient data transmission. In addition, over-water nodes aid the transmission of underwater network to improve the communication quality. With the proposed communication architecture, the coastal network can provide high-quality communication service to traffics with different quality-of-service (QoS) requirements.
{"title":"A LTE-based communication architecture for coastal networks","authors":"Yanli Xu, Shengming Jiang, Feng Liu","doi":"10.1145/2999504.3001068","DOIUrl":"https://doi.org/10.1145/2999504.3001068","url":null,"abstract":"Currently, the coastal communication is mainly provided by satellite networks, which are expensive with low transmission rate and unable to support underwater communication efficiently. In this work, we propose a communication architecture for coastal network based on long term evolution (LTE) cellular networks in which a cellular network architecture is designed for the maritime communication scenario. Some key technologies of next-generation cellular networks such as device-to-device (D2D) and multiple input multiple output (MIMO) are integrated into the proposed architecture to support more efficient data transmission. In addition, over-water nodes aid the transmission of underwater network to improve the communication quality. With the proposed communication architecture, the coastal network can provide high-quality communication service to traffics with different quality-of-service (QoS) requirements.","PeriodicalId":378624,"journal":{"name":"Proceedings of the 11th International Conference on Underwater Networks & Systems","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128841171","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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