Pub Date : 2021-08-31DOI: 10.1109/UComms50339.2021.9598040
D. Green, John Dellamorte, Jim Dellamorte
During the development of the JANUS Standard, the focus was on transmit description, supported by a “vanilla” receiver design. It was explicitly assumed that vendors would meet or exceed the vanilla receiver through their own efforts. As described by the JANUS “WIKI,” the community now has a basic frequency hopped, non-coherently received methodology useful for a limited set of applications. Extending the list of applications will require additional receiver capabilities and resources, while one (at least) may require a more capable transmitter. This paper does not explicitly suggest standards, rather it advocates for development and informal community adoption of algorithms and methods designed to enhance performance and utility of common signaling methods. Within any list of potential upgrades for JANUS, the following four are important: a) compensation for severe frequency dependent fading; b) multi-access support and interference reduction; c) compensation for range rate (relative speed); and d) precision ranging while retaining standard noncoherent acquisition robustness). We have implemented solutions for each of these items in our Popoto modems, and each has significantly enhanced communications performance. The authors are prepared to support a community effort by providing detailed algorithmic definitions for these upgrades. However, given the short paper format of this conference, we restrict the discussions to overview and examples of our approaches.
{"title":"Enhancing JANUS Signaling","authors":"D. Green, John Dellamorte, Jim Dellamorte","doi":"10.1109/UComms50339.2021.9598040","DOIUrl":"https://doi.org/10.1109/UComms50339.2021.9598040","url":null,"abstract":"During the development of the JANUS Standard, the focus was on transmit description, supported by a “vanilla” receiver design. It was explicitly assumed that vendors would meet or exceed the vanilla receiver through their own efforts. As described by the JANUS “WIKI,” the community now has a basic frequency hopped, non-coherently received methodology useful for a limited set of applications. Extending the list of applications will require additional receiver capabilities and resources, while one (at least) may require a more capable transmitter. This paper does not explicitly suggest standards, rather it advocates for development and informal community adoption of algorithms and methods designed to enhance performance and utility of common signaling methods. Within any list of potential upgrades for JANUS, the following four are important: a) compensation for severe frequency dependent fading; b) multi-access support and interference reduction; c) compensation for range rate (relative speed); and d) precision ranging while retaining standard noncoherent acquisition robustness). We have implemented solutions for each of these items in our Popoto modems, and each has significantly enhanced communications performance. The authors are prepared to support a community effort by providing detailed algorithmic definitions for these upgrades. However, given the short paper format of this conference, we restrict the discussions to overview and examples of our approaches.","PeriodicalId":371411,"journal":{"name":"2021 Fifth Underwater Communications and Networking Conference (UComms)","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114216548","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 : 2021-08-31DOI: 10.1109/UComms50339.2021.9598053
Bahr Alexander, Schill Felix, Martin Igor
Free-space optical (FSO) communication offers much higher data rates when compared to other available underwater communication technologies. It has been used for decades in scientific and military applications, but until recently no commercial products were available. With the advent of commercially available FSO technology, the number of applications in the commercial and scientific domain has greatly expanded. This paper provides a short overview over commercially available FSO technology and highlights their use in current and future projects.
{"title":"Practical applications of free-space optical underwater communication","authors":"Bahr Alexander, Schill Felix, Martin Igor","doi":"10.1109/UComms50339.2021.9598053","DOIUrl":"https://doi.org/10.1109/UComms50339.2021.9598053","url":null,"abstract":"Free-space optical (FSO) communication offers much higher data rates when compared to other available underwater communication technologies. It has been used for decades in scientific and military applications, but until recently no commercial products were available. With the advent of commercially available FSO technology, the number of applications in the commercial and scientific domain has greatly expanded. This paper provides a short overview over commercially available FSO technology and highlights their use in current and future projects.","PeriodicalId":371411,"journal":{"name":"2021 Fifth Underwater Communications and Networking Conference (UComms)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123428524","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 : 2021-08-31DOI: 10.1109/UComms50339.2021.9598097
Thomas C. Furfaro, Andrew Bouchard, Gary L. Davies, Martijn van Riet
In response to a charge to address “Autonomy in Limited-Communication Environments,” the NATO SCI-288 Research Task Group determined that the aspect of this topic most relevant to a NATO context is communications for multivehicle operations between assets from different nations using different autonomy mission software. In order to facilitate such operations, the task group developed a conceptual shared message set for mission management, allowing tasks to be shared among autonomous assets and teams of autonomous assets by integration with this message set rather than requiring separate integrations between individual software solutions. Following the design efforts of the task group as a whole, four members of the group were able to secure resources for a synthetic demonstration and separately refined the message set and created a reference implementation. This implementation team integrated four different autonomy software solutions with the reference implementation and in October 2019 demonstrated successful joint execution of a synthetic mine countermeasures mission using the message set.
{"title":"A Task-Centric Messaging Model for Federated Autonomous Collaboration","authors":"Thomas C. Furfaro, Andrew Bouchard, Gary L. Davies, Martijn van Riet","doi":"10.1109/UComms50339.2021.9598097","DOIUrl":"https://doi.org/10.1109/UComms50339.2021.9598097","url":null,"abstract":"In response to a charge to address “Autonomy in Limited-Communication Environments,” the NATO SCI-288 Research Task Group determined that the aspect of this topic most relevant to a NATO context is communications for multivehicle operations between assets from different nations using different autonomy mission software. In order to facilitate such operations, the task group developed a conceptual shared message set for mission management, allowing tasks to be shared among autonomous assets and teams of autonomous assets by integration with this message set rather than requiring separate integrations between individual software solutions. Following the design efforts of the task group as a whole, four members of the group were able to secure resources for a synthetic demonstration and separately refined the message set and created a reference implementation. This implementation team integrated four different autonomy software solutions with the reference implementation and in October 2019 demonstrated successful joint execution of a synthetic mine countermeasures mission using the message set.","PeriodicalId":371411,"journal":{"name":"2021 Fifth Underwater Communications and Networking Conference (UComms)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132588873","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 : 2021-08-31DOI: 10.1109/UComms50339.2021.9598067
T. Shimura, Y. Kida, Mitsuyasu Deguchi, Yoshitaka Watanabe, Y. Maeda
The Japan Agency for Marine-Earth Science and Technology (JAMSTEC) operates several unmanned and manned underwater vehicles for scientific research in deep water. Recently, we have developed a new high-rate underwater acoustic communication system, or acoustic modem, for vertical uplink data transmission from these vehicles. This acoustic modem uses single-carrier modulation with a decision feedback equalizer (DFE), and it has been demonstrated that the modem's performance is very stable under the Doppler effect and much better than that of orthogonal frequency division multiplexing (OFDM). In 2019, a successor acoustic modem was developed for a lander operable to a depth of 11,000 m. In an at-sea experiment conducted at a depth of 6,180 m, an effective data rate of 98.9 kbps was achieved, using the $mathbf{18pm 6.25{kHz}}$ frequency band with 256 quadrature amplitude modulation (QAM). In an experiment at a depth of 9,230 m, an effective data rate of 69.24 kbps was achieved, using the $mathbf{18pm 5{kHz}}$ frequency band with 128QAM. Thus, it was demonstrated that the performance of this acoustic modem exceeds 600 kbps $times$ km with the index of communication data rate $times$ range.
{"title":"High-rate underwater acoustic communication at over 600 kbps $times$ km for vertical uplink data transmission on a full-depth lander system","authors":"T. Shimura, Y. Kida, Mitsuyasu Deguchi, Yoshitaka Watanabe, Y. Maeda","doi":"10.1109/UComms50339.2021.9598067","DOIUrl":"https://doi.org/10.1109/UComms50339.2021.9598067","url":null,"abstract":"The Japan Agency for Marine-Earth Science and Technology (JAMSTEC) operates several unmanned and manned underwater vehicles for scientific research in deep water. Recently, we have developed a new high-rate underwater acoustic communication system, or acoustic modem, for vertical uplink data transmission from these vehicles. This acoustic modem uses single-carrier modulation with a decision feedback equalizer (DFE), and it has been demonstrated that the modem's performance is very stable under the Doppler effect and much better than that of orthogonal frequency division multiplexing (OFDM). In 2019, a successor acoustic modem was developed for a lander operable to a depth of 11,000 m. In an at-sea experiment conducted at a depth of 6,180 m, an effective data rate of 98.9 kbps was achieved, using the $mathbf{18pm 6.25{kHz}}$ frequency band with 256 quadrature amplitude modulation (QAM). In an experiment at a depth of 9,230 m, an effective data rate of 69.24 kbps was achieved, using the $mathbf{18pm 5{kHz}}$ frequency band with 128QAM. Thus, it was demonstrated that the performance of this acoustic modem exceeds 600 kbps $times$ km with the index of communication data rate $times$ range.","PeriodicalId":371411,"journal":{"name":"2021 Fifth Underwater Communications and Networking Conference (UComms)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123567525","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 : 2021-08-31DOI: 10.1109/UComms50339.2021.9598102
Konstantinos Pelekanakis, S. Yildirim, Georgios Sklivanitis, R. Petroccia, J. Alves, D. Pados
During the Rapid Environmental Picture 2018 (REP18) sea trial, two underwater acoustic nodes (Alice and Bob) exchanged 897 channel probes over different ranges and environmental conditions. In this short paper, Alice and Bob independently process their received probes offline with the aim to generate a cryptographic key based on Physical Layer Security (PLS). Using their estimated Channel Impulse Responses (CIRs), they compute and quantize four pre-agreed channel features. Eve is a simulated eavesdropper who is aware of the PLS algorithm, the 3D positions of Alice and Bob and the acoustic properties of the environment. Eve uses the de facto standard Bellhop acoustic simulator to predict the bi-directional CIRs between Alice and Bob and compute her own quantized features. We calculate the Bit Disagreement Ratio (BDR), which is a function of the number of disagreeing bits between a pair of nodes. Our results confirm that the proposed features are robust enough to yield a lower BDR between Alice and Bob than that for Eve. The BDR impact on reconciliation and secret key generation is studied in a subsequent paper [1].
{"title":"Physical Layer Security against an Informed Eavesdropper in Underwater Acoustic Channels: Feature Extraction and Quantization","authors":"Konstantinos Pelekanakis, S. Yildirim, Georgios Sklivanitis, R. Petroccia, J. Alves, D. Pados","doi":"10.1109/UComms50339.2021.9598102","DOIUrl":"https://doi.org/10.1109/UComms50339.2021.9598102","url":null,"abstract":"During the Rapid Environmental Picture 2018 (REP18) sea trial, two underwater acoustic nodes (Alice and Bob) exchanged 897 channel probes over different ranges and environmental conditions. In this short paper, Alice and Bob independently process their received probes offline with the aim to generate a cryptographic key based on Physical Layer Security (PLS). Using their estimated Channel Impulse Responses (CIRs), they compute and quantize four pre-agreed channel features. Eve is a simulated eavesdropper who is aware of the PLS algorithm, the 3D positions of Alice and Bob and the acoustic properties of the environment. Eve uses the de facto standard Bellhop acoustic simulator to predict the bi-directional CIRs between Alice and Bob and compute her own quantized features. We calculate the Bit Disagreement Ratio (BDR), which is a function of the number of disagreeing bits between a pair of nodes. Our results confirm that the proposed features are robust enough to yield a lower BDR between Alice and Bob than that for Eve. The BDR impact on reconciliation and secret key generation is studied in a subsequent paper [1].","PeriodicalId":371411,"journal":{"name":"2021 Fifth Underwater Communications and Networking Conference (UComms)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124886111","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 : 2021-08-31DOI: 10.1109/UComms50339.2021.9598131
Prasad Anjangi, M. Chitre, Manu Ignatius, Chinmay Pendharkar
The prime functionality of underwater acoustic modems is communication. It is known that spatial diversity can provide improved communication performance, in the form of increased data rate or extended range. While spatial diversity is traditionally harnessed by having multiple antennas connected to a single modem, we show that multiple receiver modems can also be used cooperatively to leverage spatial diversity. One can also get much larger separation between modems than possible with multi-antenna systems. We present the design framework, protocol implementation and the performance results of a distributed spatial diversity receiver system. The system comprises of spatially separated receivers exchanging the information received over the long-range underwater acoustic link to cooperatively decode the received information. We demonstrated this technique in Singapore marina with one modem as a transmitter and two modems as receivers. The receivers cooperate over a short-range wired/wireless network to share the received copy of signals and decode the information transmitted. The advantages of such a system are observed in the performance analysis presented.
{"title":"Distributed Spatial Diversity Enabled Receiver System For An Underwater Acoustic Link","authors":"Prasad Anjangi, M. Chitre, Manu Ignatius, Chinmay Pendharkar","doi":"10.1109/UComms50339.2021.9598131","DOIUrl":"https://doi.org/10.1109/UComms50339.2021.9598131","url":null,"abstract":"The prime functionality of underwater acoustic modems is communication. It is known that spatial diversity can provide improved communication performance, in the form of increased data rate or extended range. While spatial diversity is traditionally harnessed by having multiple antennas connected to a single modem, we show that multiple receiver modems can also be used cooperatively to leverage spatial diversity. One can also get much larger separation between modems than possible with multi-antenna systems. We present the design framework, protocol implementation and the performance results of a distributed spatial diversity receiver system. The system comprises of spatially separated receivers exchanging the information received over the long-range underwater acoustic link to cooperatively decode the received information. We demonstrated this technique in Singapore marina with one modem as a transmitter and two modems as receivers. The receivers cooperate over a short-range wired/wireless network to share the received copy of signals and decode the information transmitted. The advantages of such a system are observed in the performance analysis presented.","PeriodicalId":371411,"journal":{"name":"2021 Fifth Underwater Communications and Networking Conference (UComms)","volume":"176 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123008088","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 : 2021-08-31DOI: 10.1109/UComms50339.2021.9598045
S. Gladysz, M. Segel, José P Montoya, I. Toselli, Osvaldo Javier Galicia Gasperin, K. Stein
We report on progress made in the last few years at Fraunhofer IOSB with regards to understanding the effects that underwater turbulence poses for laser-based communications and also with regards to design and implementation of efficient wavefront correction strategies. We have pursued, through parallel efforts, analytical modelling of light propagation through oceanic turbulence, conception and validation of turbulence characterization methods, and construction of “wavefront sensorless” adaptive optics for underwater communications.
{"title":"Modelling, Measurement and Correction of Underwater Turbulence Effects on Optical Communications","authors":"S. Gladysz, M. Segel, José P Montoya, I. Toselli, Osvaldo Javier Galicia Gasperin, K. Stein","doi":"10.1109/UComms50339.2021.9598045","DOIUrl":"https://doi.org/10.1109/UComms50339.2021.9598045","url":null,"abstract":"We report on progress made in the last few years at Fraunhofer IOSB with regards to understanding the effects that underwater turbulence poses for laser-based communications and also with regards to design and implementation of efficient wavefront correction strategies. We have pursued, through parallel efforts, analytical modelling of light propagation through oceanic turbulence, conception and validation of turbulence characterization methods, and construction of “wavefront sensorless” adaptive optics for underwater communications.","PeriodicalId":371411,"journal":{"name":"2021 Fifth Underwater Communications and Networking Conference (UComms)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116004117","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 : 2021-08-31DOI: 10.1109/UComms50339.2021.9598114
George Sklivanitis, P. Markopoulos, D. Pados, R. Diamant
We consider the problem of robust localization of a set of underwater network nodes, based on pairwise distance measurements. Localization plays a key role in underwater network optimization, as accurate node positioning enables location-aware scheduling, data routing, and geo-referencing of the collected underwater sensor data. State-of-the-art graph localization approaches include variations of the classical multidimensional scaling (MDS) algorithm, modified to handle unlabelled, missing, and noisy distance measurements. In this paper, we present MAD-MDS, a robust method for graph localization from incomplete and outlier corrupted pair-wise distance measurements. The proposed method first conducts outlier excision by means of Median Absolute Deviation (MAD). Then, MAD-MDS performs rank-based completion of the distance matrix, to estimate missing measurements. As a last step, MAD-MDS applies MDS to the reconstructed distance matrix, to estimate the coordinates of the underwater network nodes. Numerical studies on both sparsely and fully connected network graphs as well as on data from past sea experiments corroborate that MAD-MDS attains high coordinate-estimation performance for sparsely connected network graphs and high corruption variance.
{"title":"Robust Graph Localization for Underwater Acoustic Networks","authors":"George Sklivanitis, P. Markopoulos, D. Pados, R. Diamant","doi":"10.1109/UComms50339.2021.9598114","DOIUrl":"https://doi.org/10.1109/UComms50339.2021.9598114","url":null,"abstract":"We consider the problem of robust localization of a set of underwater network nodes, based on pairwise distance measurements. Localization plays a key role in underwater network optimization, as accurate node positioning enables location-aware scheduling, data routing, and geo-referencing of the collected underwater sensor data. State-of-the-art graph localization approaches include variations of the classical multidimensional scaling (MDS) algorithm, modified to handle unlabelled, missing, and noisy distance measurements. In this paper, we present MAD-MDS, a robust method for graph localization from incomplete and outlier corrupted pair-wise distance measurements. The proposed method first conducts outlier excision by means of Median Absolute Deviation (MAD). Then, MAD-MDS performs rank-based completion of the distance matrix, to estimate missing measurements. As a last step, MAD-MDS applies MDS to the reconstructed distance matrix, to estimate the coordinates of the underwater network nodes. Numerical studies on both sparsely and fully connected network graphs as well as on data from past sea experiments corroborate that MAD-MDS attains high coordinate-estimation performance for sparsely connected network graphs and high corruption variance.","PeriodicalId":371411,"journal":{"name":"2021 Fifth Underwater Communications and Networking Conference (UComms)","volume":"20 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133729433","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 : 2021-08-31DOI: 10.1109/UComms50339.2021.9598156
Y. Rong, S. Nordholm, A. Duncan
In this paper, we first analyze the factors that affect the capacity of underwater optical wireless communication (UOWC) systems through deriving a new tight capacity upperbound. We find that the system capacity depends on the light wavelength in a complicated manner. Then we compare UOWC with the underwater acoustic communication (UAC) technology in terms of channel capacity, communication range, and energy efficiency. We show that UOWC requires a much lower energy-per-bit than UAC for short range communication. Finally, we study the multi-hop communication technique to extend the range of UOWC. The optimal number of hops is derived taking into account the cost of deploying relay nodes. Our study provides useful guidelines in designing a hybrid underwater acoustic/optical communication system which can achieve an increased range-rate product for underwater wireless communication.
{"title":"On the Capacity of Underwater Optical Wireless Communication Systems","authors":"Y. Rong, S. Nordholm, A. Duncan","doi":"10.1109/UComms50339.2021.9598156","DOIUrl":"https://doi.org/10.1109/UComms50339.2021.9598156","url":null,"abstract":"In this paper, we first analyze the factors that affect the capacity of underwater optical wireless communication (UOWC) systems through deriving a new tight capacity upperbound. We find that the system capacity depends on the light wavelength in a complicated manner. Then we compare UOWC with the underwater acoustic communication (UAC) technology in terms of channel capacity, communication range, and energy efficiency. We show that UOWC requires a much lower energy-per-bit than UAC for short range communication. Finally, we study the multi-hop communication technique to extend the range of UOWC. The optimal number of hops is derived taking into account the cost of deploying relay nodes. Our study provides useful guidelines in designing a hybrid underwater acoustic/optical communication system which can achieve an increased range-rate product for underwater wireless communication.","PeriodicalId":371411,"journal":{"name":"2021 Fifth Underwater Communications and Networking Conference (UComms)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133182143","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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