Pub Date : 2009-03-30DOI: 10.1109/SARNOF.2009.4850274
H. Uzunalioglu, R. Nagarajan, G. Atkinson
Traffic matrices play a crucial role in designing, dimensioning, and evolving communication networks. Recent measurement studies, however, found that there is generally a mismatch between traffic matrices and the actual network traffic. Since the link sizing and routing plans depend on the traffic matrix, this mismatch would result in inefficient use of the network resources. Traffic Engineering addresses this problem by utilizing alternate paths to distribute the traffic uniformly over the network. However, traffic engineering is applied at yearly or multi-year intervals, and may require re-routing of existing connections. In this paper, we introduce a route selection algorithm that operates during VPN set-up request arrivals to determine the best path for the incoming requests to achieve efficient use of the network resources. Our algorithm utilizes the concept of shadow prices and distributes the traffic uniformly across the network making better use of deployed network resources which in turn minimizes the network operator's overall infrastructure capital and operational expenses. The performance modeling results show that our solution outperforms shortest path and greedy routing algorithms. Furthermore, we show that an approximate lower bound, which may never be achieved by a feasible algorithm, is only 25% better in network cost compared to our solution.
{"title":"Transport Resource Manager for VPN routing in packet networks","authors":"H. Uzunalioglu, R. Nagarajan, G. Atkinson","doi":"10.1109/SARNOF.2009.4850274","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850274","url":null,"abstract":"Traffic matrices play a crucial role in designing, dimensioning, and evolving communication networks. Recent measurement studies, however, found that there is generally a mismatch between traffic matrices and the actual network traffic. Since the link sizing and routing plans depend on the traffic matrix, this mismatch would result in inefficient use of the network resources. Traffic Engineering addresses this problem by utilizing alternate paths to distribute the traffic uniformly over the network. However, traffic engineering is applied at yearly or multi-year intervals, and may require re-routing of existing connections. In this paper, we introduce a route selection algorithm that operates during VPN set-up request arrivals to determine the best path for the incoming requests to achieve efficient use of the network resources. Our algorithm utilizes the concept of shadow prices and distributes the traffic uniformly across the network making better use of deployed network resources which in turn minimizes the network operator's overall infrastructure capital and operational expenses. The performance modeling results show that our solution outperforms shortest path and greedy routing algorithms. Furthermore, we show that an approximate lower bound, which may never be achieved by a feasible algorithm, is only 25% better in network cost compared to our solution.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133977497","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850349
F. Muhammad, A. Stephan, J. Baudais, J. Hélard
The problem of minimization of mean bit error rate (BER) of a linear precoded orthogonal frequency division multiplexing (LP-OFDM) system is considered. The discrete bit loading algorithms are proposed, which minimize the mean BER of the system for a target bit rate under a peak power constraint. The results are shown for a power line communication system using a well-known multipath channel model. The other, more common, robustness optimization problem is the margin maximization. The obtained results are compared with those of the margin maximization for both OFDM and LP-OFDM schemes. It is shown that the proposed LP-OFDM allocation performs better than the previously published algorithms for poor SNR. Moreover, it is observed that the LP-OFDM allocations have lower computational complexity than the OFDM allocations.
{"title":"Mean BER minimization loading algorithm for linear precoded OFDM","authors":"F. Muhammad, A. Stephan, J. Baudais, J. Hélard","doi":"10.1109/SARNOF.2009.4850349","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850349","url":null,"abstract":"The problem of minimization of mean bit error rate (BER) of a linear precoded orthogonal frequency division multiplexing (LP-OFDM) system is considered. The discrete bit loading algorithms are proposed, which minimize the mean BER of the system for a target bit rate under a peak power constraint. The results are shown for a power line communication system using a well-known multipath channel model. The other, more common, robustness optimization problem is the margin maximization. The obtained results are compared with those of the margin maximization for both OFDM and LP-OFDM schemes. It is shown that the proposed LP-OFDM allocation performs better than the previously published algorithms for poor SNR. Moreover, it is observed that the LP-OFDM allocations have lower computational complexity than the OFDM allocations.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127595534","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850357
P. Cotae, Fatou Mbengue
A comparison of the optimal power allocation for a Gaussian vector channel subject to sum power constraint under water filling principle and inverse eigenvalue problem is given. We focus on the overloaded multipath DS - CDMA systems when the channel information is known at both transmitter and receiver. We generalize the sum of power constraint for each cell by considering p-norm matrices, and we provide numerical and graphical results for an overloaded CDMA cell in the presence and the absence of the multipath fading.
{"title":"On the power efficient resource allocation for the overloaded multipath CDMA systems","authors":"P. Cotae, Fatou Mbengue","doi":"10.1109/SARNOF.2009.4850357","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850357","url":null,"abstract":"A comparison of the optimal power allocation for a Gaussian vector channel subject to sum power constraint under water filling principle and inverse eigenvalue problem is given. We focus on the overloaded multipath DS - CDMA systems when the channel information is known at both transmitter and receiver. We generalize the sum of power constraint for each cell by considering p-norm matrices, and we provide numerical and graphical results for an overloaded CDMA cell in the presence and the absence of the multipath fading.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"200-202 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130700907","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850320
A. J. Jahromi, H. Aghaeinia, Saeed Daneshmand
In this paper, we investigate cooperative diversity in the uplink of a code division multiple access (CDMA) system, in which users cooperate by relaying each other's messages to the Base Station (BS). We assume that the spreading waveforms are not orthogonal and hence multiple access interference (MAI) might exist at both the relay nodes as well as the BS. This MAI causes cooperative diversity gain to decrease. To alleviate this problem, the maximum likelihood multiuser detector (MUD) is introduced. We assume that direct and inter-user Channel State Information (CSI) is present at the BS, and it can use this information to optimally combine received signals from both direct and relay paths. Simulation results show that the proposed Maximum Likelihood (ML) detector can exploit maximum diversity and also cancel MAI at the BS. However, the complexity of this detector increases exponentially with the number of users. To address this issue, a Genetic Algorithm (GA) is employed and it will be shown that the proposed detector can achieve a near-optimum bit-error-rate performance with a reasonable complexity.
{"title":"On multi-user detection in CDMA based cooperative networks","authors":"A. J. Jahromi, H. Aghaeinia, Saeed Daneshmand","doi":"10.1109/SARNOF.2009.4850320","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850320","url":null,"abstract":"In this paper, we investigate cooperative diversity in the uplink of a code division multiple access (CDMA) system, in which users cooperate by relaying each other's messages to the Base Station (BS). We assume that the spreading waveforms are not orthogonal and hence multiple access interference (MAI) might exist at both the relay nodes as well as the BS. This MAI causes cooperative diversity gain to decrease. To alleviate this problem, the maximum likelihood multiuser detector (MUD) is introduced. We assume that direct and inter-user Channel State Information (CSI) is present at the BS, and it can use this information to optimally combine received signals from both direct and relay paths. Simulation results show that the proposed Maximum Likelihood (ML) detector can exploit maximum diversity and also cancel MAI at the BS. However, the complexity of this detector increases exponentially with the number of users. To address this issue, a Genetic Algorithm (GA) is employed and it will be shown that the proposed detector can achieve a near-optimum bit-error-rate performance with a reasonable complexity.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130896523","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850281
R. Nichols
Due to high traffic demands, networks are increasingly required to implement techniques which support prioritization. Internet Quality of Service (QoS) approaches such as Differentiated Services (Diffserv) and Integrated Services (Intserv) can function in a traditional provider network. However, in some domains these techniques are not straightforward to implement. Wireless networks are increasingly using directional networking capabilities to handle increased traffic demands. However, prioritization techniques for such networks are in the research phase. In this paper we propose an approach to prioritize traffic in these types of networks using the principles of Quality of Information (QoI). We build on previous work which established topology control and routing approaches for directional networks using Delay/Disruption-Tolerant Networking (DTN). We extend this framework to support varied information quality.
{"title":"QoI in DTN-based directional networks","authors":"R. Nichols","doi":"10.1109/SARNOF.2009.4850281","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850281","url":null,"abstract":"Due to high traffic demands, networks are increasingly required to implement techniques which support prioritization. Internet Quality of Service (QoS) approaches such as Differentiated Services (Diffserv) and Integrated Services (Intserv) can function in a traditional provider network. However, in some domains these techniques are not straightforward to implement. Wireless networks are increasingly using directional networking capabilities to handle increased traffic demands. However, prioritization techniques for such networks are in the research phase. In this paper we propose an approach to prioritize traffic in these types of networks using the principles of Quality of Information (QoI). We build on previous work which established topology control and routing approaches for directional networks using Delay/Disruption-Tolerant Networking (DTN). We extend this framework to support varied information quality.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131168390","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850341
A. Khaleghi, I. Balasingham
Ultra wideband (UWB) is a promising technology for wireless body area networks (WBANs). This paper investigates the wave propagation in the frequency range of 1 – 6 GHz for non-line-of-sight (NLOS) channels from front to back of a human body by considering different wave polarizations: perpendicular and tangential with respect to the body. Time domain electromagnetic (EM) simulation using the anatomical model of a human body assuming frequency dependent tissue properties is conducted. A significant enhancement of the on-body communication link is identified by exploiting the transceiver antennas at the perpendicular to body polarizations. As the results, the radiograph of the energy density and delay spread of the NLOS channels with different antenna polarizations are presented.
{"title":"On human body ultra wideband channel characterizations for different wave polarizations","authors":"A. Khaleghi, I. Balasingham","doi":"10.1109/SARNOF.2009.4850341","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850341","url":null,"abstract":"Ultra wideband (UWB) is a promising technology for wireless body area networks (WBANs). This paper investigates the wave propagation in the frequency range of 1 – 6 GHz for non-line-of-sight (NLOS) channels from front to back of a human body by considering different wave polarizations: perpendicular and tangential with respect to the body. Time domain electromagnetic (EM) simulation using the anatomical model of a human body assuming frequency dependent tissue properties is conducted. A significant enhancement of the on-body communication link is identified by exploiting the transceiver antennas at the perpendicular to body polarizations. As the results, the radiograph of the energy density and delay spread of the NLOS channels with different antenna polarizations are presented.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133290300","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850377
N. Maxemchuk
Collaborative driving systems are complex, distributed systems that control physical vehicles. They can reduce accidents, decrease fuel consumption, reduce commute times and increase the capacity of highways. However, errors in their implementation can cause unsafe conditions that result in the loss of human life. Our objective is to find ways to design, verify, and quantify safety in these systems. In this paper we describe a collaborative driving system that assists in safely and quickly merging vehicles when highways merge, following tolls, and at construction or accident sites. We describe 1) an architecture that partitions the application into modules that can be tested and modified independently, 2) a communication protocol that provides an unconventional set of services that simplifies the implementation of the system, and 3) a strategy for cooperation between the human operator and the system.
{"title":"Safety issues in collaborative vehicle control","authors":"N. Maxemchuk","doi":"10.1109/SARNOF.2009.4850377","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850377","url":null,"abstract":"Collaborative driving systems are complex, distributed systems that control physical vehicles. They can reduce accidents, decrease fuel consumption, reduce commute times and increase the capacity of highways. However, errors in their implementation can cause unsafe conditions that result in the loss of human life. Our objective is to find ways to design, verify, and quantify safety in these systems. In this paper we describe a collaborative driving system that assists in safely and quickly merging vehicles when highways merge, following tolls, and at construction or accident sites. We describe 1) an architecture that partitions the application into modules that can be tested and modified independently, 2) a communication protocol that provides an unconventional set of services that simplifies the implementation of the system, and 3) a strategy for cooperation between the human operator and the system.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134635981","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850328
S. Cevher, M. U. Uyar, M. Fecko, J. Sucec, S. Samtani
Increasing efficient use of resources, such as network bandwidth, battery life and processing power, is one of the most important challenges in multicast group design for mission-critical networks. In this paper, we present an efficient technique for multicast group planning in a mission-critical network. Our technique increases the number of transmission links shared by any two users in a shortest-path multicast tree while keeping the unwanted traffic received by users within acceptable limits. We conduct simulation experiments which show that the multicast group assignments from our approach significantly increase bandwidth efficiency of multicasting.
{"title":"Efficient management of multicast communications in mission-critical networks","authors":"S. Cevher, M. U. Uyar, M. Fecko, J. Sucec, S. Samtani","doi":"10.1109/SARNOF.2009.4850328","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850328","url":null,"abstract":"Increasing efficient use of resources, such as network bandwidth, battery life and processing power, is one of the most important challenges in multicast group design for mission-critical networks. In this paper, we present an efficient technique for multicast group planning in a mission-critical network. Our technique increases the number of transmission links shared by any two users in a shortest-path multicast tree while keeping the unwanted traffic received by users within acceptable limits. We conduct simulation experiments which show that the multicast group assignments from our approach significantly increase bandwidth efficiency of multicasting.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127394709","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850287
T. Szymanski
Bounds on the end-to-end delay, jitter and service lead/lag for all statically-provisioned multimedia traffic flows routed through any network of Input-Queued (IQ) switches are presented. A Recursive Fair Stochastic Matrix Decomposition (RFSMD) algorithm is used to determine near-optimal transmission schedules for each switch, where the jitter and service lead/lag of all flows are simultaneously bounded by K · IIDT time-slots for small constant K, where IIDT denotes the Ideal Inter-Departure Time for each flow. It is established that: (a) the number of buffered cells per flow per switch is near-minimal and bounded by O(K) cells, (b) the end-to-end queueing delay along an H-hop path is near-minimal and bounded by O(KH · IIDT ) time-slots, (c) the end-to-end jitter and service lead/lag are near-minimal and bounded byO(K · IIDT ) time-slots (the jitter is not cumulative), and (d) all network-introduced jitter can be provably removed using small playback buffers with O(K) cells. It follows that all statically-provisioned traffic flows, including VOIP, IPTV and Video-on-Demand traffic, can be delivered with essentially-perfect QoS even at 100% loads, thereby achieving the optimal statistical multiplexing gain. The bounds also apply when the crossbar switches use a combination of IQs and crosspoint queues. These theories explain several exhaustive results which have recently been presented in the literature.
{"title":"Bounds on end-to-end delay and jitter in input-buffered and internally-buffered IP networks","authors":"T. Szymanski","doi":"10.1109/SARNOF.2009.4850287","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850287","url":null,"abstract":"Bounds on the end-to-end delay, jitter and service lead/lag for all statically-provisioned multimedia traffic flows routed through any network of Input-Queued (IQ) switches are presented. A Recursive Fair Stochastic Matrix Decomposition (RFSMD) algorithm is used to determine near-optimal transmission schedules for each switch, where the jitter and service lead/lag of all flows are simultaneously bounded by K · IIDT time-slots for small constant K, where IIDT denotes the Ideal Inter-Departure Time for each flow. It is established that: (a) the number of buffered cells per flow per switch is near-minimal and bounded by O(K) cells, (b) the end-to-end queueing delay along an H-hop path is near-minimal and bounded by O(KH · IIDT ) time-slots, (c) the end-to-end jitter and service lead/lag are near-minimal and bounded byO(K · IIDT ) time-slots (the jitter is not cumulative), and (d) all network-introduced jitter can be provably removed using small playback buffers with O(K) cells. It follows that all statically-provisioned traffic flows, including VOIP, IPTV and Video-on-Demand traffic, can be delivered with essentially-perfect QoS even at 100% loads, thereby achieving the optimal statistical multiplexing gain. The bounds also apply when the crossbar switches use a combination of IQs and crosspoint queues. These theories explain several exhaustive results which have recently been presented in the literature.","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115990855","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 : 2009-03-30DOI: 10.1109/SARNOF.2009.4850364
S. Sebbah, B. Jaumard
We propose a new flexible design approach of protection plans in survivable WDM networks by using protection structures with no predefined shapes in order to maximize the protected working capacity in an end-to-end basis. Previous design approaches of survivable WDM based on Protected Working Capacity Envelope (PWCE) have looked at the optimization problem of maximizing the protected capacity on a link basis, independently of the source and destination nodes of the potential traffic. Moreover, those approaches have only investigated the design problem with pre-configured protection cycles (p-cycles).
{"title":"Design of flexible protection plans in survivable WDM networks: An application to PWCE","authors":"S. Sebbah, B. Jaumard","doi":"10.1109/SARNOF.2009.4850364","DOIUrl":"https://doi.org/10.1109/SARNOF.2009.4850364","url":null,"abstract":"We propose a new flexible design approach of protection plans in survivable WDM networks by using protection structures with no predefined shapes in order to maximize the protected working capacity in an end-to-end basis. Previous design approaches of survivable WDM based on Protected Working Capacity Envelope (PWCE) have looked at the optimization problem of maximizing the protected capacity on a link basis, independently of the source and destination nodes of the potential traffic. Moreover, those approaches have only investigated the design problem with pre-configured protection cycles (p-cycles).","PeriodicalId":230233,"journal":{"name":"2009 IEEE Sarnoff Symposium","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123544895","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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