Pub Date : 2007-04-02DOI: 10.1109/WONS.2007.340468
Pietro Michiardi, Guillaume Urvoy-Keller
In this paper we focus on the problem of content distribution in wireless ad hoc networks. Our goal is to study the performance of a cooperative content distribution mechanism to distribute content from one source to a potentially large number of destinations. Despite the large literature on content distribution schemes available for wired settings we argue that the very nature of the underlying ad hoc network poses new challenges that cannot be addressed with current schemes. We propose a cooperative peer-to-peer scheme that allows parallel download of the content based on swarming protocols. Our scheme builds a distribution overlay network that takes into account traffic locality and allows peers to trade parts of the content while sustaining cooperation. We evaluate through simulations the performance of our scheme for different static scenarios using a variety of metrics to characterize the impact of our solution at different layers of the system stack. Our results highlight the great benefits of our solution in terms of system fairness, achievable throughput, and energy consumption. We also study the scalability properties of our solution under the extended network model
{"title":"Performance analysis of cooperative content distribution in wireless ad hoc networks","authors":"Pietro Michiardi, Guillaume Urvoy-Keller","doi":"10.1109/WONS.2007.340468","DOIUrl":"https://doi.org/10.1109/WONS.2007.340468","url":null,"abstract":"In this paper we focus on the problem of content distribution in wireless ad hoc networks. Our goal is to study the performance of a cooperative content distribution mechanism to distribute content from one source to a potentially large number of destinations. Despite the large literature on content distribution schemes available for wired settings we argue that the very nature of the underlying ad hoc network poses new challenges that cannot be addressed with current schemes. We propose a cooperative peer-to-peer scheme that allows parallel download of the content based on swarming protocols. Our scheme builds a distribution overlay network that takes into account traffic locality and allows peers to trade parts of the content while sustaining cooperation. We evaluate through simulations the performance of our scheme for different static scenarios using a variety of metrics to characterize the impact of our solution at different layers of the system stack. Our results highlight the great benefits of our solution in terms of system fairness, achievable throughput, and energy consumption. We also study the scalability properties of our solution under the extended network model","PeriodicalId":151450,"journal":{"name":"2007 Fourth Annual Conference on Wireless on Demand Network Systems and Services","volume":"217 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122000470","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 : 2007-04-02DOI: 10.1109/WONS.2007.340478
Christian Lochert, Björn Scheuermann, M. Caliskan, M. Mauve
In this paper we consider information dissemination in vehicular ad-hoc networks (VANETs) in city scenarios. Information dissemination is an important building block of many proposed VANET applications. These applications need a certain dissemination performance to work satisfactorily. This is critical during the rollout of VANETs, when only few cars participate. After analytical considerations, we focus on simulations using a detailed model of a whole city. We assess the dissemination performance depending on the amount of equipped vehicles on the road. For few equipped vehicles, we show that dissemination speed and coverage will not be sufficient. Therefore, we propose to use specialized, but simple and cheap infrastructure, stationary supporting units (SSUs). If a small number of SSUs is installed in a city and connected via some backbone network, the dissemination performance improves dramatically, especially during the VANET rollout phase. Thus, SSUs allow for a faster and earlier rollout of working, dissemination-based VANET applications
{"title":"The feasibility of information dissemination in vehicular ad-hoc networks","authors":"Christian Lochert, Björn Scheuermann, M. Caliskan, M. Mauve","doi":"10.1109/WONS.2007.340478","DOIUrl":"https://doi.org/10.1109/WONS.2007.340478","url":null,"abstract":"In this paper we consider information dissemination in vehicular ad-hoc networks (VANETs) in city scenarios. Information dissemination is an important building block of many proposed VANET applications. These applications need a certain dissemination performance to work satisfactorily. This is critical during the rollout of VANETs, when only few cars participate. After analytical considerations, we focus on simulations using a detailed model of a whole city. We assess the dissemination performance depending on the amount of equipped vehicles on the road. For few equipped vehicles, we show that dissemination speed and coverage will not be sufficient. Therefore, we propose to use specialized, but simple and cheap infrastructure, stationary supporting units (SSUs). If a small number of SSUs is installed in a city and connected via some backbone network, the dissemination performance improves dramatically, especially during the VANET rollout phase. Thus, SSUs allow for a faster and earlier rollout of working, dissemination-based VANET applications","PeriodicalId":151450,"journal":{"name":"2007 Fourth Annual Conference on Wireless on Demand Network Systems and Services","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129972151","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 : 2007-04-02DOI: 10.1109/WONS.2007.340467
F. Manne, S. Wang, Q. Xin
We study the communication primitive of broadcasting (one-to-all communication) in known topology radio networks, i.e., where for each primitive the schedule of transmissions is precomputed based on full knowledge about the size and the topology of the network. We show that radio broadcasting can be completed in D+O(logn) time units in planar graphs of size n, diameter D, which improves the currently best known D+O(log3 n) time schedule proposed by Elkin and Kortsarz in (2005) [SODA'05], and 3D time schedule due to Gasieniec, Peleg and Xin in (2005) [PODC'05]
{"title":"Faster radio broadcasting in planar graphs","authors":"F. Manne, S. Wang, Q. Xin","doi":"10.1109/WONS.2007.340467","DOIUrl":"https://doi.org/10.1109/WONS.2007.340467","url":null,"abstract":"We study the communication primitive of broadcasting (one-to-all communication) in known topology radio networks, i.e., where for each primitive the schedule of transmissions is precomputed based on full knowledge about the size and the topology of the network. We show that radio broadcasting can be completed in D+O(logn) time units in planar graphs of size n, diameter D, which improves the currently best known D+O(log3 n) time schedule proposed by Elkin and Kortsarz in (2005) [SODA'05], and 3D time schedule due to Gasieniec, Peleg and Xin in (2005) [PODC'05]","PeriodicalId":151450,"journal":{"name":"2007 Fourth Annual Conference on Wireless on Demand Network Systems and Services","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125548180","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 : 2007-04-02DOI: 10.1109/WONS.2007.340475
Felix Schmidt-Eisenlohr, M. Torrent-Moreno, Jens Mittag, H. Hartenstein
Due to the large amount of nodes that could comprise a vehicular network, simulation is a valuable tool used for the design and analysis of inter-vehicle communication protocols. In this paper we first describe all the components of a simulation framework that has ns-2 as core building block. Our main contributions are an accurate implementation of the MAC and PHY modules adjusted to vehicular environments together with a well defined set of metrics to evaluate communication protocols for vehicular networks. Second, we make use of the simulation framework to perform a detailed analysis of periodic exchange of broadcast messages when adjusting transmission power and packet generation rate for different propagation models
{"title":"Simulation platform for inter-vehicle communications and analysis of periodic information exchange","authors":"Felix Schmidt-Eisenlohr, M. Torrent-Moreno, Jens Mittag, H. Hartenstein","doi":"10.1109/WONS.2007.340475","DOIUrl":"https://doi.org/10.1109/WONS.2007.340475","url":null,"abstract":"Due to the large amount of nodes that could comprise a vehicular network, simulation is a valuable tool used for the design and analysis of inter-vehicle communication protocols. In this paper we first describe all the components of a simulation framework that has ns-2 as core building block. Our main contributions are an accurate implementation of the MAC and PHY modules adjusted to vehicular environments together with a well defined set of metrics to evaluate communication protocols for vehicular networks. Second, we make use of the simulation framework to perform a detailed analysis of periodic exchange of broadcast messages when adjusting transmission power and packet generation rate for different propagation models","PeriodicalId":151450,"journal":{"name":"2007 Fourth Annual Conference on Wireless on Demand Network Systems and Services","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115430716","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 : 2007-04-02DOI: 10.1109/WONS.2007.340481
Jia-liang Lu, F. Valois, D. Barthel
We propose in this paper a low-energy self-organization scheme (LEGOS), a simple event-driven and leader-based self-organization. It provides and maintains a communication structure for wireless ad hoc sensor networks with low energy consumption. To achieve low power operation, LEGOS employs a quick join procedure with low message cost for newly arrived sensor nodes. The use of periodic Hello messages is avoided in the design of LEGOS, which has a strong impact on energy saving. LEGOS guarantees a low-cardinality dominating node set selection in the network. The resulting communication structure can adapt itself with the growth of the network service area. LEGOS is a completely localized algorithm. We also prove that LEGOS has low computation complexity and low message cost through simply analysis. Through simulations, we show that LEGOS provides up to 20% of extra energy savings compared to other self-organization schemes when using the same distributed MAC scheduling. Our results illustrate the need for simple and low-energy self-organization to effectively realize energy efficient sensor network applications
{"title":"Low-energy self-organization scheme for wireless ad hoc sensor networks","authors":"Jia-liang Lu, F. Valois, D. Barthel","doi":"10.1109/WONS.2007.340481","DOIUrl":"https://doi.org/10.1109/WONS.2007.340481","url":null,"abstract":"We propose in this paper a low-energy self-organization scheme (LEGOS), a simple event-driven and leader-based self-organization. It provides and maintains a communication structure for wireless ad hoc sensor networks with low energy consumption. To achieve low power operation, LEGOS employs a quick join procedure with low message cost for newly arrived sensor nodes. The use of periodic Hello messages is avoided in the design of LEGOS, which has a strong impact on energy saving. LEGOS guarantees a low-cardinality dominating node set selection in the network. The resulting communication structure can adapt itself with the growth of the network service area. LEGOS is a completely localized algorithm. We also prove that LEGOS has low computation complexity and low message cost through simply analysis. Through simulations, we show that LEGOS provides up to 20% of extra energy savings compared to other self-organization schemes when using the same distributed MAC scheduling. Our results illustrate the need for simple and low-energy self-organization to effectively realize energy efficient sensor network applications","PeriodicalId":151450,"journal":{"name":"2007 Fourth Annual Conference on Wireless on Demand Network Systems and Services","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133475208","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 : 2007-04-02DOI: 10.1109/WONS.2007.340477
H. Füßler, S. Schnaufer, M. Transier, Wolfgang Effelsberg
VANETs, or vehicular ad-hoc networks, have recently gained scientific and commercial interest. In fact, they have drawn many people from neighboring fields like general mobile ad-hoc networks (MANETs), into their wake. In this invited paper, we discuss the history of vehicular ad-hoc networks from our perspective. In detail, we will show the early vision of creating a huge MANET that would facilitate cheap and ubiquitous communication on the ISM bands, and how this vision was reduced to cars sending emergency information in a geographically limited area. Also, we will describe how new challenges emerge from these new constraints, and then argue that VANETs are still an interesting research area
{"title":"Vehicular ad-hoc networks: from vision to reality and back","authors":"H. Füßler, S. Schnaufer, M. Transier, Wolfgang Effelsberg","doi":"10.1109/WONS.2007.340477","DOIUrl":"https://doi.org/10.1109/WONS.2007.340477","url":null,"abstract":"VANETs, or vehicular ad-hoc networks, have recently gained scientific and commercial interest. In fact, they have drawn many people from neighboring fields like general mobile ad-hoc networks (MANETs), into their wake. In this invited paper, we discuss the history of vehicular ad-hoc networks from our perspective. In detail, we will show the early vision of creating a huge MANET that would facilitate cheap and ubiquitous communication on the ISM bands, and how this vision was reduced to cars sending emergency information in a geographically limited area. Also, we will describe how new challenges emerge from these new constraints, and then argue that VANETs are still an interesting research area","PeriodicalId":151450,"journal":{"name":"2007 Fourth Annual Conference on Wireless on Demand Network Systems and Services","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116285879","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 : 2007-04-02DOI: 10.1109/WONS.2007.340480
Thomas Fuhrmann
Scalable source routing (SSR) is a novel routing approach for large unstructured networks such as mobile ad hoc networks, mesh networks, or sensor-actuator networks. It is especially suited for organically growing networks of many resource-limited mobile devices supported by a few fixed-wired nodes. SSR is a full-fledged network layer routing protocol that directly provides the semantics of a structured peer-to-peer network. Hence, it can serve as an efficient basis for fully decentralized applications on mobile devices. SSR combines source routing in the physical network with Chord-like routing in the virtual ring formed by the address space. Message forwarding greedily decreases the distance in the virtual ring while preferring physically short paths. Thereby, scalability is achieved without imposing artificial hierarchies or assigning location-dependent addresses
{"title":"Performance of scalable source routing in hybrid MANETs","authors":"Thomas Fuhrmann","doi":"10.1109/WONS.2007.340480","DOIUrl":"https://doi.org/10.1109/WONS.2007.340480","url":null,"abstract":"Scalable source routing (SSR) is a novel routing approach for large unstructured networks such as mobile ad hoc networks, mesh networks, or sensor-actuator networks. It is especially suited for organically growing networks of many resource-limited mobile devices supported by a few fixed-wired nodes. SSR is a full-fledged network layer routing protocol that directly provides the semantics of a structured peer-to-peer network. Hence, it can serve as an efficient basis for fully decentralized applications on mobile devices. SSR combines source routing in the physical network with Chord-like routing in the virtual ring formed by the address space. Message forwarding greedily decreases the distance in the virtual ring while preferring physically short paths. Thereby, scalability is achieved without imposing artificial hierarchies or assigning location-dependent addresses","PeriodicalId":151450,"journal":{"name":"2007 Fourth Annual Conference on Wireless on Demand Network Systems and Services","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128827173","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 : 2007-04-02DOI: 10.1109/WONS.2007.340492
M. Hauspie, I. Simplot-Ryl
Ad hoc networks are distributed, self-organized wireless networks. By their nature, it is easy for a malicious user to enter this kind of networks with the intention of disturbing the way they are behaving by not participating to the network. This kind of behavior is a form of selfishness where nodes want to save their energy by not routing packets. Many solutions based on virtual currency mechanisms or on reputation mechanisms have been shown to increase the networks reliability for this kind of problems. We advocate in this paper that this issue can be treated with local algorithms that have minor drawbacks compared to sophisticated solutions developed in other works. We conduct an evaluation of our solution, which shows satisfying enough results to be used in civilian spontaneous networks
{"title":"Enhancing nodes cooperation in ad hoc networks","authors":"M. Hauspie, I. Simplot-Ryl","doi":"10.1109/WONS.2007.340492","DOIUrl":"https://doi.org/10.1109/WONS.2007.340492","url":null,"abstract":"Ad hoc networks are distributed, self-organized wireless networks. By their nature, it is easy for a malicious user to enter this kind of networks with the intention of disturbing the way they are behaving by not participating to the network. This kind of behavior is a form of selfishness where nodes want to save their energy by not routing packets. Many solutions based on virtual currency mechanisms or on reputation mechanisms have been shown to increase the networks reliability for this kind of problems. We advocate in this paper that this issue can be treated with local algorithms that have minor drawbacks compared to sophisticated solutions developed in other works. We conduct an evaluation of our solution, which shows satisfying enough results to be used in civilian spontaneous networks","PeriodicalId":151450,"journal":{"name":"2007 Fourth Annual Conference on Wireless on Demand Network Systems and Services","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128998873","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 : 2007-04-02DOI: 10.1109/WONS.2007.340470
V. Mhatre, Henrik Lundgren, C. Diot
We propose expected throughput, ETP, a new and improved routing metric for wireless mesh networks. In contrast to previously proposed routing metrics, ETP takes into account the bandwidth sharing mechanism of 802.11 DCF. In this mechanism, contending links with lower nominal bit rate degrade the throughput of faster links. It is evident that this MAC layer interaction impacts the link quality, and subsequently, the route quality. We develop an analytical model to capture the above interaction, and use it to define ETP. ETP is therefore expected to yield more accurate throughput estimations than existing routing metrics. Furthermore, ETP is suitable as a routing metric in multi-rate as well as multi-channel mesh networks
{"title":"MAC-aware routing in wireless mesh networks","authors":"V. Mhatre, Henrik Lundgren, C. Diot","doi":"10.1109/WONS.2007.340470","DOIUrl":"https://doi.org/10.1109/WONS.2007.340470","url":null,"abstract":"We propose expected throughput, ETP, a new and improved routing metric for wireless mesh networks. In contrast to previously proposed routing metrics, ETP takes into account the bandwidth sharing mechanism of 802.11 DCF. In this mechanism, contending links with lower nominal bit rate degrade the throughput of faster links. It is evident that this MAC layer interaction impacts the link quality, and subsequently, the route quality. We develop an analytical model to capture the above interaction, and use it to define ETP. ETP is therefore expected to yield more accurate throughput estimations than existing routing metrics. Furthermore, ETP is suitable as a routing metric in multi-rate as well as multi-channel mesh networks","PeriodicalId":151450,"journal":{"name":"2007 Fourth Annual Conference on Wireless on Demand Network Systems and Services","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121061571","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 : 2007-04-02DOI: 10.1109/WONS.2007.340490
Rama Vuyyuru, K. Oguchi
Vehicular communication is an emerging technology that has lot of potential to support transportation safety, traffic information and other ITS related applications. Due to its unique challenges and infrastructure requirements it is very difficult to evaluate new communication technologies in real world. A good simulation environment is required to evaluate new technologies in close to real-world situations. In this paper we proposed a new simulation framework for vehicular communication protocol evaluation and used this simulation tool to evaluate the performance of event dissemination protocol in realistic city traffic environment. Goal of the event dissemination algorithm is to achieve maximum coverage while keeping the network overhead at minimum. We presented the implementation of custom driving simulation model and propagation simulation model and used them to evaluate the event dissemination protocol with realistic vehicular mobility in urban traffic scenario. Simulation model presented in this paper provides plug-in type modules to extend the features for a particular simulation feature, whether it is for new communication protocol or new driver behavior model
{"title":"Vehicle-to- vehicle ad hoc communication protocol evaluation using realistic simulation framework","authors":"Rama Vuyyuru, K. Oguchi","doi":"10.1109/WONS.2007.340490","DOIUrl":"https://doi.org/10.1109/WONS.2007.340490","url":null,"abstract":"Vehicular communication is an emerging technology that has lot of potential to support transportation safety, traffic information and other ITS related applications. Due to its unique challenges and infrastructure requirements it is very difficult to evaluate new communication technologies in real world. A good simulation environment is required to evaluate new technologies in close to real-world situations. In this paper we proposed a new simulation framework for vehicular communication protocol evaluation and used this simulation tool to evaluate the performance of event dissemination protocol in realistic city traffic environment. Goal of the event dissemination algorithm is to achieve maximum coverage while keeping the network overhead at minimum. We presented the implementation of custom driving simulation model and propagation simulation model and used them to evaluate the event dissemination protocol with realistic vehicular mobility in urban traffic scenario. Simulation model presented in this paper provides plug-in type modules to extend the features for a particular simulation feature, whether it is for new communication protocol or new driver behavior model","PeriodicalId":151450,"journal":{"name":"2007 Fourth Annual Conference on Wireless on Demand Network Systems and Services","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117136076","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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