By definition, the operation of an asynchronous power save protocol permits an arbitrary distribution of nodes' wakeup schedules. This wakeup schedule distribution creates an uncoordinated pattern of times at which nodes attempt to transmit. Intuitively, we would expect that some patterns are more (or less) favorable than others for a given traffic pattern. We investigate the impact of this wakeup pattern on network capacity and present simulation data showing that the capacity associated with the best wakeup patterns is significantly larger than that of the worst. This result not only gives insight to the behavior of such protocols, but also acts as a feasibility study showing the potential benefit of mechanisms by which nodes adapt their wakeup schedules to obtain improved performance.
{"title":"The Impact of Wakeup Schedule Distribution in Asynchronous Power Save Protocols on the Performance of Multihop Wireless Networks","authors":"L. Feeney, C. Rohner, B. Ahlgren","doi":"10.1109/WCNC.2007.581","DOIUrl":"https://doi.org/10.1109/WCNC.2007.581","url":null,"abstract":"By definition, the operation of an asynchronous power save protocol permits an arbitrary distribution of nodes' wakeup schedules. This wakeup schedule distribution creates an uncoordinated pattern of times at which nodes attempt to transmit. Intuitively, we would expect that some patterns are more (or less) favorable than others for a given traffic pattern. We investigate the impact of this wakeup pattern on network capacity and present simulation data showing that the capacity associated with the best wakeup patterns is significantly larger than that of the worst. This result not only gives insight to the behavior of such protocols, but also acts as a feasibility study showing the potential benefit of mechanisms by which nodes adapt their wakeup schedules to obtain improved performance.","PeriodicalId":292621,"journal":{"name":"2007 IEEE Wireless Communications and Networking Conference","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129980550","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}
Multi-channel wireless mesh networks (WMNs) aim to perform ubiquitous wireless broadband network access. In WMNs, much attention has been paid to the problem of resource allocation, i.e., how to utilize multiple orthogonal channels and multiple communication radios to enhance the aggregate throughput efficiently. Routing and resource allocation correlatively determine the performance of WMNs. Thus, this paper proposes a route-aware resource allocation algorithm to distribute total traffic load over diverse radios and channels based on route information. The simulation results show that route-aware resource allocation can balance the workload among all available resources (radios and channels) and achieve the higher aggregate throughput and fairness.
{"title":"Route-Aware Load-Balanced Resource Allocation for Wireless Mesh Networks","authors":"K. Lin, Cheng-Fu Chou","doi":"10.1109/WCNC.2007.572","DOIUrl":"https://doi.org/10.1109/WCNC.2007.572","url":null,"abstract":"Multi-channel wireless mesh networks (WMNs) aim to perform ubiquitous wireless broadband network access. In WMNs, much attention has been paid to the problem of resource allocation, i.e., how to utilize multiple orthogonal channels and multiple communication radios to enhance the aggregate throughput efficiently. Routing and resource allocation correlatively determine the performance of WMNs. Thus, this paper proposes a route-aware resource allocation algorithm to distribute total traffic load over diverse radios and channels based on route information. The simulation results show that route-aware resource allocation can balance the workload among all available resources (radios and channels) and achieve the higher aggregate throughput and fairness.","PeriodicalId":292621,"journal":{"name":"2007 IEEE Wireless Communications and Networking Conference","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134229205","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 paper proposed a frequency diversity technique for Bluetooth, namely dual channel transmission (DCT), to reduce the packet error rate (PER) due to inter-piconet interference when multiple Bluetooth piconets coexist. With DCT, the same packet is transmitted on two distinct frequency hopped channels simultaneously, and the power used in each channel is half of what would be used in single channel transmission (SCT). A packet is successfully received if at least one channel survives. There is a tradeoff between the increased reliability due to the diversity offered by DCT, and the potentially increased interference due to the use of extra channel. The authors evaluate the performance of DCT when co-channel and adjacent channel interference, as well as wireless propagation characteristics are considered. It is shown that with DCT, the PER is significantly lower than that of SCT when a small number of piconets coexist. Numerical simulations validate the analysis and demonstrate the effectiveness of DCT.
{"title":"Evaluation of Co-channel and Adjacent Channel Interference for Multiple Bluetooth Piconets with Dual Channel Transmission","authors":"Jingli Li, Xiangqian Liu","doi":"10.1109/WCNC.2007.440","DOIUrl":"https://doi.org/10.1109/WCNC.2007.440","url":null,"abstract":"The paper proposed a frequency diversity technique for Bluetooth, namely dual channel transmission (DCT), to reduce the packet error rate (PER) due to inter-piconet interference when multiple Bluetooth piconets coexist. With DCT, the same packet is transmitted on two distinct frequency hopped channels simultaneously, and the power used in each channel is half of what would be used in single channel transmission (SCT). A packet is successfully received if at least one channel survives. There is a tradeoff between the increased reliability due to the diversity offered by DCT, and the potentially increased interference due to the use of extra channel. The authors evaluate the performance of DCT when co-channel and adjacent channel interference, as well as wireless propagation characteristics are considered. It is shown that with DCT, the PER is significantly lower than that of SCT when a small number of piconets coexist. Numerical simulations validate the analysis and demonstrate the effectiveness of DCT.","PeriodicalId":292621,"journal":{"name":"2007 IEEE Wireless Communications and Networking Conference","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134419996","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}
This paper describes a combined modulation scheme for time hopping ultra wideband (TH-UWB) radio systems based on orthogonal pulse position modulation (OPPM) and bi-orthogonal pulse shape modulation (BPSM). A set of M=2k symbols are constructed by using L = 2l orthogonal pulse positions and N = 2k-l-1 biorthogonal pulses, where k > 1 and l are nonnegative integers such that 0 les l les k-1. The selection of the number of pulse positions and pulses depends on the system performance and the availability of orthogonal pulses with estimable auto-correlation properties. This scheme allows an increase in the number of bits per symbol and consequently, reduces the duration of the pulse repetition interval which is obtain by increasing the number of orthogonal pulses. The proposed scheme achieves higher data rate by using a large number of orthogonal pulses in the same pulse repetition interval. It also reduces the system complexity by half by introducing antipodal version of orthogonal pulses. The proposed transmission scheme is analyzed through computer simulations in a multipath channel using two sets of orthogonal pulses.
提出了一种基于正交脉冲位置调制(OPPM)和双正交脉冲形状调制(BPSM)的跳时超宽带(TH-UWB)无线电系统组合调制方案。利用L = 2l个正交脉冲位置和N =2k - L -1个双正交脉冲构造了M=2k个符号集，其中k > 1, L为非负整数，使得0小于L小于k-1。脉冲位置和脉冲数的选择取决于系统性能和具有可估计自相关特性的正交脉冲的可用性。该方案允许增加每个符号的位数，从而减少通过增加正交脉冲的数量而获得的脉冲重复间隔的持续时间。该方案通过在相同的脉冲重复间隔内使用大量的正交脉冲来实现更高的数据速率。通过引入正交脉冲的对映版本，使系统的复杂度降低了一半。通过计算机仿真，利用两组正交脉冲在多径信道中分析了所提出的传输方案。
{"title":"M-ary Signaling for Ultra Wideband Communication Systems Based on Pulse Position and Orthogonal Pulse Shape Modulation","authors":"S. Majhi, A. Madhukumar, A. Premkumar, F. Chin","doi":"10.1109/WCNC.2007.519","DOIUrl":"https://doi.org/10.1109/WCNC.2007.519","url":null,"abstract":"This paper describes a combined modulation scheme for time hopping ultra wideband (TH-UWB) radio systems based on orthogonal pulse position modulation (OPPM) and bi-orthogonal pulse shape modulation (BPSM). A set of M=2k symbols are constructed by using L = 2l orthogonal pulse positions and N = 2k-l-1 biorthogonal pulses, where k > 1 and l are nonnegative integers such that 0 les l les k-1. The selection of the number of pulse positions and pulses depends on the system performance and the availability of orthogonal pulses with estimable auto-correlation properties. This scheme allows an increase in the number of bits per symbol and consequently, reduces the duration of the pulse repetition interval which is obtain by increasing the number of orthogonal pulses. The proposed scheme achieves higher data rate by using a large number of orthogonal pulses in the same pulse repetition interval. It also reduces the system complexity by half by introducing antipodal version of orthogonal pulses. The proposed transmission scheme is analyzed through computer simulations in a multipath channel using two sets of orthogonal pulses.","PeriodicalId":292621,"journal":{"name":"2007 IEEE Wireless Communications and Networking Conference","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133915515","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}
Suhua Tang, Masahiro Watanabe, N. Kadowaki, S. Obana
Performance of mobile ad hoc networks (MANET) routing protocols may be greatly degraded due to involvement of weak links in the routes. One solution is to use directional antenna to improve link quality. The other is to less prefer weak links. In the experiments we found that even with the two methods the system performance is still limited in the presence of mobility and multipath fading due to the following facts: (1) beam scanning overhead and frequent beam variations, (2) route instability due to metric variation and false link breaks. Then we improve it by three schemes: (i) Calculate the antenna beam by position information, (ii) Calculate a stable link metric from the expectation value of received signal strength indication (RSSI). (iii) Avoid false link breaks. These schemes are suitable for the scenarios where both line of sight path and multipath fading exist. The experiment and simulation results indicate that the schemes can effectively reduces PER and improve throughput of AODV in the Rician fading situations.
{"title":"Improving Routing Performance Under the Fading Environment by Utilizing Position Information","authors":"Suhua Tang, Masahiro Watanabe, N. Kadowaki, S. Obana","doi":"10.1109/WCNC.2007.776","DOIUrl":"https://doi.org/10.1109/WCNC.2007.776","url":null,"abstract":"Performance of mobile ad hoc networks (MANET) routing protocols may be greatly degraded due to involvement of weak links in the routes. One solution is to use directional antenna to improve link quality. The other is to less prefer weak links. In the experiments we found that even with the two methods the system performance is still limited in the presence of mobility and multipath fading due to the following facts: (1) beam scanning overhead and frequent beam variations, (2) route instability due to metric variation and false link breaks. Then we improve it by three schemes: (i) Calculate the antenna beam by position information, (ii) Calculate a stable link metric from the expectation value of received signal strength indication (RSSI). (iii) Avoid false link breaks. These schemes are suitable for the scenarios where both line of sight path and multipath fading exist. The experiment and simulation results indicate that the schemes can effectively reduces PER and improve throughput of AODV in the Rician fading situations.","PeriodicalId":292621,"journal":{"name":"2007 IEEE Wireless Communications and Networking Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134285647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In wireless sensor networks, in order to minimize energy consumption and extend network lifetime, some sensors are put in the sleep mode while the other sensor nodes are in the active mode for the sensing and communication tasks. In a randomized scheduling algorithm, a set of sensors work alternatively. In this paper, we provide an analytical model for the randomized scheduling algorithm, and derive detection delay and detection probability. Simulations are conducted to validate analytical results.
{"title":"Modeling Detection Metrics in Randomized Scheduling Algorithm in Wireless Sensor Networks","authors":"Yang Xiao, Hui Chen, Kui Wu, Bo Sun, Chong Liu","doi":"10.1109/WCNC.2007.685","DOIUrl":"https://doi.org/10.1109/WCNC.2007.685","url":null,"abstract":"In wireless sensor networks, in order to minimize energy consumption and extend network lifetime, some sensors are put in the sleep mode while the other sensor nodes are in the active mode for the sensing and communication tasks. In a randomized scheduling algorithm, a set of sensors work alternatively. In this paper, we provide an analytical model for the randomized scheduling algorithm, and derive detection delay and detection probability. Simulations are conducted to validate analytical results.","PeriodicalId":292621,"journal":{"name":"2007 IEEE Wireless Communications and Networking Conference","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134294432","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}
This paper introduces a mechanism allowing the network to command dynamically and individually the user equipments (UEs) to activate or deactivate receive (Rx) diversity for circuit-switched (CS) services, in order to enhance the radio capacity when needed, while saving the UEs' battery when possible. The salient features of the proposed scheme are: the possibility to tune the network capacity as a function of the load, requesting UEs to adopt a power-consuming receiver configuration only when needed by the network; the guarantee that the UEs deactivating Rx diversity is not request more power than available after a configuration change, ensuring a safe network behaviour; a small amount of feedback between the UEs and the base station (4 information bits in the uplink and one bit in the downlink, to be transmitted with a low periodicity). In addition, we describe a heuristic method for determining the most appropriate configurations of the UEs as a function of the system load. System-level simulations show that the proposed scheme allows an average peak CS capacity increase ranging between 15 % and 85% with respect to an autonomous UE configuration scheme, depending on the parametrization of the latter.
{"title":"Network-Driven Receive Diversity Activation","authors":"E. Hardouin","doi":"10.1109/WCNC.2007.339","DOIUrl":"https://doi.org/10.1109/WCNC.2007.339","url":null,"abstract":"This paper introduces a mechanism allowing the network to command dynamically and individually the user equipments (UEs) to activate or deactivate receive (Rx) diversity for circuit-switched (CS) services, in order to enhance the radio capacity when needed, while saving the UEs' battery when possible. The salient features of the proposed scheme are: the possibility to tune the network capacity as a function of the load, requesting UEs to adopt a power-consuming receiver configuration only when needed by the network; the guarantee that the UEs deactivating Rx diversity is not request more power than available after a configuration change, ensuring a safe network behaviour; a small amount of feedback between the UEs and the base station (4 information bits in the uplink and one bit in the downlink, to be transmitted with a low periodicity). In addition, we describe a heuristic method for determining the most appropriate configurations of the UEs as a function of the system load. System-level simulations show that the proposed scheme allows an average peak CS capacity increase ranging between 15 % and 85% with respect to an autonomous UE configuration scheme, depending on the parametrization of the latter.","PeriodicalId":292621,"journal":{"name":"2007 IEEE Wireless Communications and Networking Conference","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134339209","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}
Cross-layer scheduling has received an intense attention recently owing to the desire to exploit protocol interactions to design optimum systems that are adaptable to service requirements of network applications. This article discusses a Lyapunov stable power-constrained opportunistic scheduler that makes an optimum use of the wireless spectrum while guaranteeing a minimum service to all flows active in multi-flow, multiuser wireless systems. We formulate the constrained scheduling problem as a dynamic system of differential equations. We then establish a Lyapunov function for the dynamic system associated with the search for an optimum solution for the constrained convex optimization problem, and then apply Lyapunov stability theory to prove the system's convergence. The system of differential equations is used to excite a neural network whose outputs are the solutions to the constrained optimization problem.
{"title":"Performance Analysis of a Power-Constrained Cross-Layer Scheduling Using Artificial Neural Networks","authors":"A. Gyasi-Agyei","doi":"10.1109/WCNC.2007.286","DOIUrl":"https://doi.org/10.1109/WCNC.2007.286","url":null,"abstract":"Cross-layer scheduling has received an intense attention recently owing to the desire to exploit protocol interactions to design optimum systems that are adaptable to service requirements of network applications. This article discusses a Lyapunov stable power-constrained opportunistic scheduler that makes an optimum use of the wireless spectrum while guaranteeing a minimum service to all flows active in multi-flow, multiuser wireless systems. We formulate the constrained scheduling problem as a dynamic system of differential equations. We then establish a Lyapunov function for the dynamic system associated with the search for an optimum solution for the constrained convex optimization problem, and then apply Lyapunov stability theory to prove the system's convergence. The system of differential equations is used to excite a neural network whose outputs are the solutions to the constrained optimization problem.","PeriodicalId":292621,"journal":{"name":"2007 IEEE Wireless Communications and Networking Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131568743","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}
M. Pan, Jie Chen, Ruoju Liu, Z. Feng, Ying Wang, Ping Zhang
This driven by the need to promote a more efficient use of radio resources and improve the operators' profits, resource allocation has turned into a joint technical and economical problem. At the same time, as a possible enabling solution, game theory has been applied to either dynamic spectrum access (DSA) or joint radio resource management (JRRM) in wireless communication research recently. In this paper, we propose a novel DSA and JRRM combined approach to resource allocation in cooperative networks. With the scenario that distributed reconfigurable radio access networks (RAN) are controlled by different operators, the emerging concept of resource trading is introduced and new entities, such as trading agents (TA), are described. Meanwhile, Shapley value in cooperative game as well as its economic model is exploited to share the profits among the trading RANs. Numerical results show that comparing with existing DSA or JRRM methods, our scheme has better effect in maximizing the individual operator's profits and improving the efficiency of radio resources utilization.
{"title":"Dynamic Spectrum Access and Joint Radio Resource Management Combining for Resource Allocation in Cooperative Networks","authors":"M. Pan, Jie Chen, Ruoju Liu, Z. Feng, Ying Wang, Ping Zhang","doi":"10.1109/WCNC.2007.510","DOIUrl":"https://doi.org/10.1109/WCNC.2007.510","url":null,"abstract":"This driven by the need to promote a more efficient use of radio resources and improve the operators' profits, resource allocation has turned into a joint technical and economical problem. At the same time, as a possible enabling solution, game theory has been applied to either dynamic spectrum access (DSA) or joint radio resource management (JRRM) in wireless communication research recently. In this paper, we propose a novel DSA and JRRM combined approach to resource allocation in cooperative networks. With the scenario that distributed reconfigurable radio access networks (RAN) are controlled by different operators, the emerging concept of resource trading is introduced and new entities, such as trading agents (TA), are described. Meanwhile, Shapley value in cooperative game as well as its economic model is exploited to share the profits among the trading RANs. Numerical results show that comparing with existing DSA or JRRM methods, our scheme has better effect in maximizing the individual operator's profits and improving the efficiency of radio resources utilization.","PeriodicalId":292621,"journal":{"name":"2007 IEEE Wireless Communications and Networking Conference","volume":"31 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131686889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, we present a joint power control, link scheduling and rate control (PSR) algorithm for wireless ad hoc networks by using the convex optimization theory. This algorithm practically considers the power control problem in the interference-based link scheduling process, and provides a congestion control on the transport layer. Both our theoretical analysis and simulation results prove that the PSR algorithm can converge quickly and is possible for distributed implementation in the wireless ad hoc networks.
{"title":"A Joint Power Control, Link Scheduling and Rate Control Algorithm for Wireless Ad Hoc Networks","authors":"V. Zheng, Xinming Zhang, D. Liu, D. Sung","doi":"10.1109/WCNC.2007.666","DOIUrl":"https://doi.org/10.1109/WCNC.2007.666","url":null,"abstract":"In this paper, we present a joint power control, link scheduling and rate control (PSR) algorithm for wireless ad hoc networks by using the convex optimization theory. This algorithm practically considers the power control problem in the interference-based link scheduling process, and provides a congestion control on the transport layer. Both our theoretical analysis and simulation results prove that the PSR algorithm can converge quickly and is possible for distributed implementation in the wireless ad hoc networks.","PeriodicalId":292621,"journal":{"name":"2007 IEEE Wireless Communications and Networking Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130902558","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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