Pub Date : 2010-12-01DOI: 10.1109/GLOCOMW.2010.5701678
A. Mahmood, A. Jabbar, Egeman K. Cetinkaya, J. Sterbenz
Realistic network topologies are crucial for network research and are commonly used for the analysis, simulation, and evaluation of various mechanisms and protocols. In this paper, we discuss network topology models to generate physical topologies for backbone networks. In order to gain better understanding of current topologies and engineer networks for the future, it is necessary to generate realistic physical topologies that are governed by the infrastructure as opposed to only logical topologies that are governed by policy or higher-layer abstractions. The objective of this work is to present the principles that are key to node distributions of realistic topologies and the challenges involved. We argue that the dominant factors that influence the location of the PoPs are population density distribution and the technology penetration of a given region. Hence we implement a clustering algorithm to accurately predict the location of PoPs and later explore cost constrained models to generate realistic physical topologies.
{"title":"Deriving network topologies from real world constraints","authors":"A. Mahmood, A. Jabbar, Egeman K. Cetinkaya, J. Sterbenz","doi":"10.1109/GLOCOMW.2010.5701678","DOIUrl":"https://doi.org/10.1109/GLOCOMW.2010.5701678","url":null,"abstract":"Realistic network topologies are crucial for network research and are commonly used for the analysis, simulation, and evaluation of various mechanisms and protocols. In this paper, we discuss network topology models to generate physical topologies for backbone networks. In order to gain better understanding of current topologies and engineer networks for the future, it is necessary to generate realistic physical topologies that are governed by the infrastructure as opposed to only logical topologies that are governed by policy or higher-layer abstractions. The objective of this work is to present the principles that are key to node distributions of realistic topologies and the challenges involved. We argue that the dominant factors that influence the location of the PoPs are population density distribution and the technology penetration of a given region. Hence we implement a clustering algorithm to accurately predict the location of PoPs and later explore cost constrained models to generate realistic physical topologies.","PeriodicalId":232205,"journal":{"name":"2010 IEEE Globecom Workshops","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121296130","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 : 2010-12-01DOI: 10.1109/GLOCOMW.2010.5700459
Sida Lv, Zhifeng Zhao, Honggang Zhang
LT codes promise reliable transmissions of data over erasure channels. They also work satisfactorily over interference channels after cyclic redundancy check (CRC) is introduced into the transmission system. In this paper, we will propose a set of codes named improved binary repetition codes (IBRCs) derived from block repetition codes using cyclic shifts. With comparatively lower complexity, IBRCs serve as an inner channel codes concatenated after LT pre-coding to maintain the reliability of LT codes over interference channels without using additional CRC bits. We want to show that IBRC is capable of replacing the conventional schemes involving CRC at larger SNRs with the same performance but much lower complexity, while at lower SNRs, if we take the tradeoff between performance and complexity into consideration, IBRC challenges the conventional CRC schemes. We will give numerical results to demonstrate that the proposed solution is an effective scheme worth evaluating and bringing into practice.
{"title":"Reliable data transmission using IBRC and LT codes over AWGN channels","authors":"Sida Lv, Zhifeng Zhao, Honggang Zhang","doi":"10.1109/GLOCOMW.2010.5700459","DOIUrl":"https://doi.org/10.1109/GLOCOMW.2010.5700459","url":null,"abstract":"LT codes promise reliable transmissions of data over erasure channels. They also work satisfactorily over interference channels after cyclic redundancy check (CRC) is introduced into the transmission system. In this paper, we will propose a set of codes named improved binary repetition codes (IBRCs) derived from block repetition codes using cyclic shifts. With comparatively lower complexity, IBRCs serve as an inner channel codes concatenated after LT pre-coding to maintain the reliability of LT codes over interference channels without using additional CRC bits. We want to show that IBRC is capable of replacing the conventional schemes involving CRC at larger SNRs with the same performance but much lower complexity, while at lower SNRs, if we take the tradeoff between performance and complexity into consideration, IBRC challenges the conventional CRC schemes. We will give numerical results to demonstrate that the proposed solution is an effective scheme worth evaluating and bringing into practice.","PeriodicalId":232205,"journal":{"name":"2010 IEEE Globecom Workshops","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121542449","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 : 2010-12-01DOI: 10.1109/GLOCOMW.2010.5700260
A. Jagmohan, M. Franceschini, L. A. Lastras-Montaño, J. Karidis
A fundamental constraint in the use of newer NAND Flash devices in the enterprise space is the low cycling endurance of such devices. As an example, the latest 2-bit MLC devices have a cycling endurance ranging from 3K to 10K program/erase cycles. Upcoming higher-density devices are expected to have even lower endurance. In this paper we propose a coding technique called Adaptive Endurance Coding (AEC) which increases the number of program/erase cycles that a Flash device can endure. The key insight leveraged by the proposed technique is the data-dependent nature of Flash cell-wear. Data-dependent wear implies that Flash chip/device lifetime can be significantly increased by converting data into bit-patterns, prior to programming, which cause minimal wear. AEC can be used to generate a capacity-wear trade-off; for compressible data, AEC can be adapted to data compressibility in order to maximize endurance gains with low system overhead costs. The technique can be implemented in the Flash device controller without requiring any hardware changes to the device itself. We present empirical results on SLC and MLC Flash chips demonstrating the improvements in retention and bit-error rate which can be obtained via this technique, and present device-level simulation results quantifying the gains achievable by the use of AEC.
{"title":"Adaptive endurance coding for NAND Flash","authors":"A. Jagmohan, M. Franceschini, L. A. Lastras-Montaño, J. Karidis","doi":"10.1109/GLOCOMW.2010.5700260","DOIUrl":"https://doi.org/10.1109/GLOCOMW.2010.5700260","url":null,"abstract":"A fundamental constraint in the use of newer NAND Flash devices in the enterprise space is the low cycling endurance of such devices. As an example, the latest 2-bit MLC devices have a cycling endurance ranging from 3K to 10K program/erase cycles. Upcoming higher-density devices are expected to have even lower endurance. In this paper we propose a coding technique called Adaptive Endurance Coding (AEC) which increases the number of program/erase cycles that a Flash device can endure. The key insight leveraged by the proposed technique is the data-dependent nature of Flash cell-wear. Data-dependent wear implies that Flash chip/device lifetime can be significantly increased by converting data into bit-patterns, prior to programming, which cause minimal wear. AEC can be used to generate a capacity-wear trade-off; for compressible data, AEC can be adapted to data compressibility in order to maximize endurance gains with low system overhead costs. The technique can be implemented in the Flash device controller without requiring any hardware changes to the device itself. We present empirical results on SLC and MLC Flash chips demonstrating the improvements in retention and bit-error rate which can be obtained via this technique, and present device-level simulation results quantifying the gains achievable by the use of AEC.","PeriodicalId":232205,"journal":{"name":"2010 IEEE Globecom Workshops","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122327546","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 : 2010-12-01DOI: 10.1109/GLOCOMW.2010.5700429
A. Azarfar, J. Frigon, B. Sansò
Although the main objectives of dynamic spectrum access and cognitive radios are to solve the problem of spectrum scarcity and usage inefficiency, we show in this paper that such capabilities can also be used to improve other performance metrics in wireless networks. We compare the performance of a Cognitive Radio (CR) network using nodes that are able to sense the spectrum and change their operating frequency in case of link failure with a Traditional Radio (TR) with static channel access and no frequency switching capability. The improvement that can be obtained by substituting TR to CR technology is evaluated for the blocking probability, utilization and system occupancy performance metrics based on a Two-state Markov chain channel model as a function of the number of users, number of channels, arrival rate, restoration time and channel occupancy. We show that there is a strong interaction between these parameters and that CR technology performs better in slowly time-varying channels while TR technology is more appropriate in fast changing channels.
{"title":"A performance comparison of cognitive versus traditional radio networks","authors":"A. Azarfar, J. Frigon, B. Sansò","doi":"10.1109/GLOCOMW.2010.5700429","DOIUrl":"https://doi.org/10.1109/GLOCOMW.2010.5700429","url":null,"abstract":"Although the main objectives of dynamic spectrum access and cognitive radios are to solve the problem of spectrum scarcity and usage inefficiency, we show in this paper that such capabilities can also be used to improve other performance metrics in wireless networks. We compare the performance of a Cognitive Radio (CR) network using nodes that are able to sense the spectrum and change their operating frequency in case of link failure with a Traditional Radio (TR) with static channel access and no frequency switching capability. The improvement that can be obtained by substituting TR to CR technology is evaluated for the blocking probability, utilization and system occupancy performance metrics based on a Two-state Markov chain channel model as a function of the number of users, number of channels, arrival rate, restoration time and channel occupancy. We show that there is a strong interaction between these parameters and that CR technology performs better in slowly time-varying channels while TR technology is more appropriate in fast changing channels.","PeriodicalId":232205,"journal":{"name":"2010 IEEE Globecom Workshops","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114186603","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 : 2010-12-01DOI: 10.1109/GLOCOMW.2010.5700247
E. Yanmaz, C. Costanzo, C. Bettstetter, W. Elmenreich
Networked unmanned aerial vehicles (UAVs) have found an increasing number of applications in recent years. In this work, we provide an analytical method to evaluate the sensor coverage performance of a UAV network, where the individual UAVs can work independently or cooperatively to achieve a common goal. More specifically, we propose a stochastic model in terms of a Markov chain including approximations for its parameters. Studying several scenarios using the Markov chain as well as simulations, we investigate the impact of network size and area size on the achieved coverage. While the Markovbased analysis is an approximation, the results are still in good agreement with the simulations.
{"title":"A discrete stochastic process for coverage analysis of autonomous UAV networks","authors":"E. Yanmaz, C. Costanzo, C. Bettstetter, W. Elmenreich","doi":"10.1109/GLOCOMW.2010.5700247","DOIUrl":"https://doi.org/10.1109/GLOCOMW.2010.5700247","url":null,"abstract":"Networked unmanned aerial vehicles (UAVs) have found an increasing number of applications in recent years. In this work, we provide an analytical method to evaluate the sensor coverage performance of a UAV network, where the individual UAVs can work independently or cooperatively to achieve a common goal. More specifically, we propose a stochastic model in terms of a Markov chain including approximations for its parameters. Studying several scenarios using the Markov chain as well as simulations, we investigate the impact of network size and area size on the achieved coverage. While the Markovbased analysis is an approximation, the results are still in good agreement with the simulations.","PeriodicalId":232205,"journal":{"name":"2010 IEEE Globecom Workshops","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115848225","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 : 2010-12-01DOI: 10.1109/GLOCOMW.2010.5700312
Qian Dong, W. Dargie, A. Schill
In wireless sensor networks, energy is a scarce resource. Collision, as one of the major sources of the energy waste for medium access control (MAC) protocols, has been extensively investigated. However, it is mostly analyzed under the “saturated situation” in which the sampling rate is assumed to be equal to or larger than the transmission rate, which does not reflect the reality in many applications. This paper relaxes this assumption to consider the “unsaturated situation” in which nodes do not always contend to seize the media. It focuses on hybrid MAC protocols which enable nodes to define sleeping schedules. We take SMAC as a model protocol to analyze how the sampling rate affects the probability of collision. But the approach can easily be applied to other hybrid protocols such as BMAC and XMAC.
{"title":"Effects of sampling rate on collision probability in hybrid MAC protocols in WSN","authors":"Qian Dong, W. Dargie, A. Schill","doi":"10.1109/GLOCOMW.2010.5700312","DOIUrl":"https://doi.org/10.1109/GLOCOMW.2010.5700312","url":null,"abstract":"In wireless sensor networks, energy is a scarce resource. Collision, as one of the major sources of the energy waste for medium access control (MAC) protocols, has been extensively investigated. However, it is mostly analyzed under the “saturated situation” in which the sampling rate is assumed to be equal to or larger than the transmission rate, which does not reflect the reality in many applications. This paper relaxes this assumption to consider the “unsaturated situation” in which nodes do not always contend to seize the media. It focuses on hybrid MAC protocols which enable nodes to define sleeping schedules. We take SMAC as a model protocol to analyze how the sampling rate affects the probability of collision. But the approach can easily be applied to other hybrid protocols such as BMAC and XMAC.","PeriodicalId":232205,"journal":{"name":"2010 IEEE Globecom Workshops","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116740174","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 : 2010-12-01DOI: 10.1109/GLOCOMW.2010.5700380
E. Michael, L. Henry
In this paper, the primary objective is to discuss the details of scalable methods for distributing certificate revocation lists and other large files using vehicle-to-vehicle and vehicle-to-infrastructure communications while taking advantage of the multi-channel operations in IEEE 1609.4. We also discuss the results from a simulation study using the ns-3 network simulator to closely replicate the WAVE environment discussed in the IEEE 802.11p and 1609 draft standards. Realistic vehicle traces were used in the simulation study. The results show that the methods developed in this research scale very well for increasing vehicle densities.
{"title":"Scalable certificate revocation list distribution in vehicular ad hoc networks","authors":"E. Michael, L. Henry","doi":"10.1109/GLOCOMW.2010.5700380","DOIUrl":"https://doi.org/10.1109/GLOCOMW.2010.5700380","url":null,"abstract":"In this paper, the primary objective is to discuss the details of scalable methods for distributing certificate revocation lists and other large files using vehicle-to-vehicle and vehicle-to-infrastructure communications while taking advantage of the multi-channel operations in IEEE 1609.4. We also discuss the results from a simulation study using the ns-3 network simulator to closely replicate the WAVE environment discussed in the IEEE 802.11p and 1609 draft standards. Realistic vehicle traces were used in the simulation study. The results show that the methods developed in this research scale very well for increasing vehicle densities.","PeriodicalId":232205,"journal":{"name":"2010 IEEE Globecom Workshops","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121604467","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 : 2010-12-01DOI: 10.1109/GLOCOMW.2010.5700417
W. O. da Costa Gustavo, F. Andrea, Victor Alvarez Roig, E. M. Preben
Femtocells are expected to take a major role on increasing the data rates on cellular network access over the next years. Cognitive Radio enabled femtocells are considered to be a promising solution to enable self-optimizing femtocells to effectively manage the inter-cell interference, especially in densely deployed femto scenarios. In this paper, two key elements of cognitive femtocells are combined: a power control algorithm and a fully distributed dynamic spectrum allocation method. The resulting solution was evaluated through system-level simulations and compared to the separate algorithms and fixed frequency reuses. The outage throughput performance of the combined algorithm exceeds all other options, proving the efficiency of the method in reducing inter-cell interference drastically.
{"title":"Interference mitigation in cognitive femtocells","authors":"W. O. da Costa Gustavo, F. Andrea, Victor Alvarez Roig, E. M. Preben","doi":"10.1109/GLOCOMW.2010.5700417","DOIUrl":"https://doi.org/10.1109/GLOCOMW.2010.5700417","url":null,"abstract":"Femtocells are expected to take a major role on increasing the data rates on cellular network access over the next years. Cognitive Radio enabled femtocells are considered to be a promising solution to enable self-optimizing femtocells to effectively manage the inter-cell interference, especially in densely deployed femto scenarios. In this paper, two key elements of cognitive femtocells are combined: a power control algorithm and a fully distributed dynamic spectrum allocation method. The resulting solution was evaluated through system-level simulations and compared to the separate algorithms and fixed frequency reuses. The outage throughput performance of the combined algorithm exceeds all other options, proving the efficiency of the method in reducing inter-cell interference drastically.","PeriodicalId":232205,"journal":{"name":"2010 IEEE Globecom Workshops","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122460705","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 multimedia framework is designed to provide easy to use services for developing multimedia applications based on an embedded platform. With the rapid advances in multimedia technology, various types of codec have been developed. Most of them achieve good performance but construct with complicated algorithms. Moreover, the current computing load of embedded system is still carried by MPU, and its burden of huge computing load leads multimedia framework to fail in real-time performance. Therefore, this paper analyzes the characteristics and demands of the multimedia frameworks. It proposes a refined interface to integrate the powerful digital signal processor for acceleration and modifies the frameworks architecture to maximize its efficiency. In our experiments, we apply Android multimedia framework as our test benchmark, and export our DSP H.264/AVC decoder into the embedded multimedia. The experimental results indicate that when the resolution becomes large, the effectiveness of the proposed architecture is about 1≃2.5 fps improved than the original frameworks. When the resolution becomes smaller, the performance increases significantly, say about 6≃7 fps improvement. Moreover, the playback could achieve the real-time performance even if the CPU which we used is less powerful than OMAP platform.
{"title":"Implementation and optimization of multimedia framework on heterogeneous multi-core platform","authors":"Yu-Lin Wang, Sung-Yen Chang, Shih-Chieh Chen, Yueh-Min Huang","doi":"10.1109/GLOCOMW.2010.5700462","DOIUrl":"https://doi.org/10.1109/GLOCOMW.2010.5700462","url":null,"abstract":"The multimedia framework is designed to provide easy to use services for developing multimedia applications based on an embedded platform. With the rapid advances in multimedia technology, various types of codec have been developed. Most of them achieve good performance but construct with complicated algorithms. Moreover, the current computing load of embedded system is still carried by MPU, and its burden of huge computing load leads multimedia framework to fail in real-time performance. Therefore, this paper analyzes the characteristics and demands of the multimedia frameworks. It proposes a refined interface to integrate the powerful digital signal processor for acceleration and modifies the frameworks architecture to maximize its efficiency. In our experiments, we apply Android multimedia framework as our test benchmark, and export our DSP H.264/AVC decoder into the embedded multimedia. The experimental results indicate that when the resolution becomes large, the effectiveness of the proposed architecture is about 1≃2.5 fps improved than the original frameworks. When the resolution becomes smaller, the performance increases significantly, say about 6≃7 fps improvement. Moreover, the playback could achieve the real-time performance even if the CPU which we used is less powerful than OMAP platform.","PeriodicalId":232205,"journal":{"name":"2010 IEEE Globecom Workshops","volume":"8 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122785797","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 : 2010-12-01DOI: 10.1109/GLOCOMW.2010.5700158
F. Callegati, A. Campi, W. Cerroni
This paper describes a possible approach to provide application-oriented functions and service definition capabilities in the Future Internet. This is achieved by introducing a Transport Service layer on top of the transport layer, that is used by the network to automatically negotiate with the applications the transport service they require. Experimental validation of the proposed solution is discussed.
{"title":"Transport service for the Future Internet: Concepts and operations","authors":"F. Callegati, A. Campi, W. Cerroni","doi":"10.1109/GLOCOMW.2010.5700158","DOIUrl":"https://doi.org/10.1109/GLOCOMW.2010.5700158","url":null,"abstract":"This paper describes a possible approach to provide application-oriented functions and service definition capabilities in the Future Internet. This is achieved by introducing a Transport Service layer on top of the transport layer, that is used by the network to automatically negotiate with the applications the transport service they require. Experimental validation of the proposed solution is discussed.","PeriodicalId":232205,"journal":{"name":"2010 IEEE Globecom Workshops","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133267391","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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