M. Louw, Marc Krull, Tavaris J. Thomas, R. Cathey, Gregory L. Frazier, Mike Weber
We explore techniques for eliciting a behavioral description from an Android smartphone app in a controlled manner. A description of app behavior is useful for performing subsequent analysis such as model checking, for example to verify the app satisfies a set of desirable security properties. Our solution is to dynamically execute the app in a customized version of the Android SDK emulator, which provides many of an app's inputs as responses to invoked API calls. A more focused set of input values computed offline are then injected to the app via hooks introduced into the Android API implementation. To dynamically monitor app behavior, we instrument the app bytecode to record control and data flows during execution. We also instrument the Android API to record all of the app's inputs and outputs. We have used this technique on the DARPA Automated Program Analysis for Cybersecurity (APAC) program to reveal hidden, triggerable attacks in independently developed challenge apps. Our framework for extracting app behavior is part of Droid Reasoning, Analysis, and Protection Engine (DRAPE), an integrated, semi-automated app behavior analysis system capable of discovering hidden malware in Android apps.
{"title":"Automated Execution Control and Dynamic Behavior Monitoring for Android (TM) Applications","authors":"M. Louw, Marc Krull, Tavaris J. Thomas, R. Cathey, Gregory L. Frazier, Mike Weber","doi":"10.1109/MILCOM.2013.168","DOIUrl":"https://doi.org/10.1109/MILCOM.2013.168","url":null,"abstract":"We explore techniques for eliciting a behavioral description from an Android smartphone app in a controlled manner. A description of app behavior is useful for performing subsequent analysis such as model checking, for example to verify the app satisfies a set of desirable security properties. Our solution is to dynamically execute the app in a customized version of the Android SDK emulator, which provides many of an app's inputs as responses to invoked API calls. A more focused set of input values computed offline are then injected to the app via hooks introduced into the Android API implementation. To dynamically monitor app behavior, we instrument the app bytecode to record control and data flows during execution. We also instrument the Android API to record all of the app's inputs and outputs. We have used this technique on the DARPA Automated Program Analysis for Cybersecurity (APAC) program to reveal hidden, triggerable attacks in independently developed challenge apps. Our framework for extracting app behavior is part of Droid Reasoning, Analysis, and Protection Engine (DRAPE), an integrated, semi-automated app behavior analysis system capable of discovering hidden malware in Android apps.","PeriodicalId":379382,"journal":{"name":"MILCOM 2013 - 2013 IEEE Military Communications Conference","volume":"138 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129253161","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}
We introduce a novel receiver based technique for estimating the spectral re-growth experienced by a modulated carrier transmitted through a power efficient nonlinear amplifier. Our approach builds upon the accurate characterization of the resulting nonlinear channel as a Volterra filter. The information contained in the filter coefficients is used to estimate the level of the principal side-lobes in the signal power-spectral density. Also, we demonstrate the ability of our proposed technique to provide accurate estimates using relatively short symbol sequences and its robustness to mismatch in amplifier characteristics. This makes our approach well suited for use in bandwidth and energy efficient satellite return links where adjacent carrier interference caused by spectral re-growth can severely impair performance.
{"title":"A Novel Receiver Based Technique for Monitoring Spectral Re-growth and Mitigating Adjacent-Channel Interference","authors":"R. I. Seshadri, B. F. Beidas, Lin-nan Lee","doi":"10.1109/MILCOM.2013.198","DOIUrl":"https://doi.org/10.1109/MILCOM.2013.198","url":null,"abstract":"We introduce a novel receiver based technique for estimating the spectral re-growth experienced by a modulated carrier transmitted through a power efficient nonlinear amplifier. Our approach builds upon the accurate characterization of the resulting nonlinear channel as a Volterra filter. The information contained in the filter coefficients is used to estimate the level of the principal side-lobes in the signal power-spectral density. Also, we demonstrate the ability of our proposed technique to provide accurate estimates using relatively short symbol sequences and its robustness to mismatch in amplifier characteristics. This makes our approach well suited for use in bandwidth and energy efficient satellite return links where adjacent carrier interference caused by spectral re-growth can severely impair performance.","PeriodicalId":379382,"journal":{"name":"MILCOM 2013 - 2013 IEEE Military Communications Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128864217","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}
Beomju Kim, Sungmook Lim, Hyungjong Kim, Sangwook Suh, J. Kwun, Sooyong Choi, Chungyong Lee, Sanghoon Lee, Daesik Hong
In this paper, we propose a non-orthogonal multiple access-based multiuser beamforming (NOMA-BF) system designed to enhance the sum capacity. In the proposed NOMA-BF system, a single BF vector is shared by two users, so that the number of supportable users can be increased. However, sharing a BF vector leads to interference from other beams as well as from the other user sharing the BF vector. Therefore, to reduce interference and improve the sum capacity, we additionally propose a clustering and power allocation algorithm. This clustering algorithm, which selects two users with high correlation and a large gain-difference between their channels, can reduce the interference from other beams and from the other user as well. Furthermore, power allocation ensures that each user's transmit power is allocated so as to maximize the sum capacity. Numerical results verify that the proposed NOMA-BF system improves the sum capacity, compared to the conventional multiuser BF system.
{"title":"Non-orthogonal Multiple Access in a Downlink Multiuser Beamforming System","authors":"Beomju Kim, Sungmook Lim, Hyungjong Kim, Sangwook Suh, J. Kwun, Sooyong Choi, Chungyong Lee, Sanghoon Lee, Daesik Hong","doi":"10.1109/MILCOM.2013.218","DOIUrl":"https://doi.org/10.1109/MILCOM.2013.218","url":null,"abstract":"In this paper, we propose a non-orthogonal multiple access-based multiuser beamforming (NOMA-BF) system designed to enhance the sum capacity. In the proposed NOMA-BF system, a single BF vector is shared by two users, so that the number of supportable users can be increased. However, sharing a BF vector leads to interference from other beams as well as from the other user sharing the BF vector. Therefore, to reduce interference and improve the sum capacity, we additionally propose a clustering and power allocation algorithm. This clustering algorithm, which selects two users with high correlation and a large gain-difference between their channels, can reduce the interference from other beams and from the other user as well. Furthermore, power allocation ensures that each user's transmit power is allocated so as to maximize the sum capacity. Numerical results verify that the proposed NOMA-BF system improves the sum capacity, compared to the conventional multiuser BF system.","PeriodicalId":379382,"journal":{"name":"MILCOM 2013 - 2013 IEEE Military Communications Conference","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126656726","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 propose a time-domain correlation-based model for wideband space-polarization MIMO channels that incorporates most important behaviors of such architectures utilizing linearly-polarized arrays. Our model incorporates power imbalance and asymmetric path K-factors and also takes into account the existence of multiple line-of-sight rays. We show that due to multiple Rician path models in the wideband system, the narrowband subband channels do not always follow the Rice distribution. This discussion is clarified with a simple two path sample channel. Therefore, it is shown that the time-domain correlation based model is more accurate than the frequency-domain counterparts which model narrowband subband channels. Furthermore, the rank of line-of-sight space-polarization MIMO channels is shown to as good or higher than the rank of co-polarized MIMO channels.
{"title":"Time-Domain Correlation-Based Multipath Modeling of Wideband Space-Polarization MIMO Channels","authors":"F. Talebi, T. Pratt","doi":"10.1109/MILCOM.2013.209","DOIUrl":"https://doi.org/10.1109/MILCOM.2013.209","url":null,"abstract":"In this paper we propose a time-domain correlation-based model for wideband space-polarization MIMO channels that incorporates most important behaviors of such architectures utilizing linearly-polarized arrays. Our model incorporates power imbalance and asymmetric path K-factors and also takes into account the existence of multiple line-of-sight rays. We show that due to multiple Rician path models in the wideband system, the narrowband subband channels do not always follow the Rice distribution. This discussion is clarified with a simple two path sample channel. Therefore, it is shown that the time-domain correlation based model is more accurate than the frequency-domain counterparts which model narrowband subband channels. Furthermore, the rank of line-of-sight space-polarization MIMO channels is shown to as good or higher than the rank of co-polarized MIMO channels.","PeriodicalId":379382,"journal":{"name":"MILCOM 2013 - 2013 IEEE Military Communications Conference","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126304016","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 work, we consider a tactical hybrid network where a military adhoc network utilizes a commercial cellular network as backbone for data traffic. It is assumed that all traffic goes through a cache at the cellular base station with Least-Recently Used (LRU) policy. We study the possibility of inferring the military traffic rate from cache hit/miss observations of a single adversary node. We show the possibility of such an inference by presenting algorithms for estimating the parameters of the hybrid network. First, we show that an adversary node can estimate the cache and workload parameters of a hybrid network by observing the hit/miss results of her queries. We then show that these estimates can be used to infer the military traffic rate.
{"title":"Inferring Military Activity in Hybrid Networks through Cache Behavior","authors":"Mostafa Dehghan, D. Goeckel, T. He, D. Towsley","doi":"10.1109/MILCOM.2013.292","DOIUrl":"https://doi.org/10.1109/MILCOM.2013.292","url":null,"abstract":"In this work, we consider a tactical hybrid network where a military adhoc network utilizes a commercial cellular network as backbone for data traffic. It is assumed that all traffic goes through a cache at the cellular base station with Least-Recently Used (LRU) policy. We study the possibility of inferring the military traffic rate from cache hit/miss observations of a single adversary node. We show the possibility of such an inference by presenting algorithms for estimating the parameters of the hybrid network. First, we show that an adversary node can estimate the cache and workload parameters of a hybrid network by observing the hit/miss results of her queries. We then show that these estimates can be used to infer the military traffic rate.","PeriodicalId":379382,"journal":{"name":"MILCOM 2013 - 2013 IEEE Military Communications Conference","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126316992","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}
Heterogeneous wireless networks have been widely studied recently for the potential to accommodate the rapidly growing data demand in wireless networks. In addition to achieving a higher data rate, power efficient transmission is also critical in providing a stable and lasting wireless access. In this work, we study the power efficient user pairing for multicasting in heterogeneous wireless networks. A combination of intelligent cell association and cooperative communications is proposed to minimize the maximum power consumption among the mobile users. Through analysis and simulation, we demonstrate the benefits of efficient cell association as well as the incorporation of cooperative communications. It shows that our proposed power efficient user pairing scheme achieves a near-optimal performance with a low complexity.
{"title":"Power Efficient User Pairing for Multicasting in Heterogeneous Wireless Networks","authors":"Yao Xiao, Y. Guan, L. Cimini, Chien-Chung Shen","doi":"10.1109/MILCOM.2013.230","DOIUrl":"https://doi.org/10.1109/MILCOM.2013.230","url":null,"abstract":"Heterogeneous wireless networks have been widely studied recently for the potential to accommodate the rapidly growing data demand in wireless networks. In addition to achieving a higher data rate, power efficient transmission is also critical in providing a stable and lasting wireless access. In this work, we study the power efficient user pairing for multicasting in heterogeneous wireless networks. A combination of intelligent cell association and cooperative communications is proposed to minimize the maximum power consumption among the mobile users. Through analysis and simulation, we demonstrate the benefits of efficient cell association as well as the incorporation of cooperative communications. It shows that our proposed power efficient user pairing scheme achieves a near-optimal performance with a low complexity.","PeriodicalId":379382,"journal":{"name":"MILCOM 2013 - 2013 IEEE Military Communications Conference","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116073292","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}
Wireless networks will play a very important role in the future of military communication networks to support a diverse range of applications such as voice, data, video, broadcast, imagery, and multicast services for users. Recently, Multi-Topology Routing (MTR) was proposed to address the optimal route selection problem by configuring routes tuned to best support different QoS classes. However, based on the static predefined network/link characteristics to create topologies, MTR may fail to adapt to frequent and fast changes of the topology in the wireless network because it does not consider dynamics such as entry/exit of wireless devices, network/link load and channel quality in the topology calculation. To resolve this limitation, we propose a requirement-driven scheme that facilitates multiple active cost functions, one cost function for each traffic class, running on the network simultaneously without predefined multiple topologies. A test bed was constructed to prove this concept. Test results also demonstrate that the router is able to select optimal routes for multiple traffic classes by using multiple routing tables in a modified OLSR (Open Link State Routing) implementation. Thus, this scheme simplifies the network planning, design, and provisioning process. Moreover, it provides a new direction for router architecture in military communication networks.
无线网络将在未来的军事通信网络中发挥非常重要的作用，为用户支持各种应用，如语音、数据、视频、广播、图像和多播服务。最近，多拓扑路由(Multi-Topology Routing, MTR)被提出，通过配置优化的路由以最好地支持不同的QoS类来解决最优路由选择问题。然而，MTR基于静态预定义的网络/链路特征来创建拓扑，由于在拓扑计算中没有考虑无线设备的进出、网络/链路负载和信道质量等动态因素，可能无法适应无线网络中拓扑的频繁快速变化。为了解决这一限制，我们提出了一种需求驱动的方案，该方案促进了多个活动成本函数，每个流量类一个成本函数，同时在网络上运行，而无需预定义多个拓扑。建立了一个试验台来验证这一概念。测试结果还表明，在改进的OLSR (Open Link State routing)实现中，路由器可以使用多个路由表为多个流量类选择最优路由。因此，该方案简化了网络规划、设计和发放过程。为军用通信网络路由器体系结构的发展提供了新的方向。
{"title":"A Design Method to Select Optimal Routes and Balance Load in Wireless Communication Networks","authors":"Mu-Cheng Wang, Steven A. Davidson, Y. Chuang","doi":"10.1109/MILCOM.2013.159","DOIUrl":"https://doi.org/10.1109/MILCOM.2013.159","url":null,"abstract":"Wireless networks will play a very important role in the future of military communication networks to support a diverse range of applications such as voice, data, video, broadcast, imagery, and multicast services for users. Recently, Multi-Topology Routing (MTR) was proposed to address the optimal route selection problem by configuring routes tuned to best support different QoS classes. However, based on the static predefined network/link characteristics to create topologies, MTR may fail to adapt to frequent and fast changes of the topology in the wireless network because it does not consider dynamics such as entry/exit of wireless devices, network/link load and channel quality in the topology calculation. To resolve this limitation, we propose a requirement-driven scheme that facilitates multiple active cost functions, one cost function for each traffic class, running on the network simultaneously without predefined multiple topologies. A test bed was constructed to prove this concept. Test results also demonstrate that the router is able to select optimal routes for multiple traffic classes by using multiple routing tables in a modified OLSR (Open Link State Routing) implementation. Thus, this scheme simplifies the network planning, design, and provisioning process. Moreover, it provides a new direction for router architecture in military communication networks.","PeriodicalId":379382,"journal":{"name":"MILCOM 2013 - 2013 IEEE Military Communications Conference","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124988662","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 is an extended abstract of the invited talk "ConfigAssure: A Science of Configuration."
本文是应邀演讲“ConfigAssure: A Science of Configuration”的扩展摘要。
{"title":"ConfigAssure: A Science of Configuration","authors":"S. Narain","doi":"10.1109/MILCOM.2013.252","DOIUrl":"https://doi.org/10.1109/MILCOM.2013.252","url":null,"abstract":"This paper is an extended abstract of the invited talk \"ConfigAssure: A Science of Configuration.\"","PeriodicalId":379382,"journal":{"name":"MILCOM 2013 - 2013 IEEE Military Communications Conference","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115144965","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 Narrowband Forwarding Protocol (NBFP) for multi-channel narrowband ad-hoc networks. This protocol proactively discovers network topology and allows nodes to choose interfaces to forward user data packets. We introduce the criteria of NBFP efficiency and provide its performance evaluation, using simulation in ns-3.
{"title":"Forwarding Protocol for Multi-channel Narrowband Ad Hoc Networks","authors":"D. Fakhriev, P. Nekrasov","doi":"10.1109/MILCOM.2013.94","DOIUrl":"https://doi.org/10.1109/MILCOM.2013.94","url":null,"abstract":"In this paper, we present a Narrowband Forwarding Protocol (NBFP) for multi-channel narrowband ad-hoc networks. This protocol proactively discovers network topology and allows nodes to choose interfaces to forward user data packets. We introduce the criteria of NBFP efficiency and provide its performance evaluation, using simulation in ns-3.","PeriodicalId":379382,"journal":{"name":"MILCOM 2013 - 2013 IEEE Military Communications Conference","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127581434","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 proposes a Deadline Based Resource Balancing (DBRB) task allocation algorithm for heterogeneous LEO small satellite networks, in which each satellite is equipped with one or more resources and limited power. So in the task allocation process, the dispatcher needs to consider the deadlines of the tasks as well as the balance of different resources. As the Map-Reduce program model is broadly adopted, a task in this network can consists of multiple subtasks. This paper schedules the subtasks based on both task deadline and resource balance. The DBRB algorithm is deployed on the head node of a cluster. It gathers the status from each cluster member and calculates their Node Importance Factors (NIFs) from the carried resources, residue power and compute capacity. The algorithm calculates the number of concurrent subtasks based on the deadlines, and allocates the subtasks to the lower NIFs first to balance the resources. The simulation results show that when cluster members carry multiple resources, resource are more balanced and rare resources serve longer in DBRB than in an Early Deadline First algorithm. We also analyze the resource balancing and average task finish time with different task deadline settings. And we show that the algorithm performs well in service isolation by serving multiple tasks with different deadlines. Moreover, the average task response time with various cluster size settings is well controlled within deadlines as well.
{"title":"Deadline Based Resource Balancing Task Allocation for Clustered Heterogeneous LEO Small Satellite Network","authors":"Jing Qin, Yonggang Liu, Xiang Mao, J. Mcnair","doi":"10.1109/MILCOM.2013.308","DOIUrl":"https://doi.org/10.1109/MILCOM.2013.308","url":null,"abstract":"This paper proposes a Deadline Based Resource Balancing (DBRB) task allocation algorithm for heterogeneous LEO small satellite networks, in which each satellite is equipped with one or more resources and limited power. So in the task allocation process, the dispatcher needs to consider the deadlines of the tasks as well as the balance of different resources. As the Map-Reduce program model is broadly adopted, a task in this network can consists of multiple subtasks. This paper schedules the subtasks based on both task deadline and resource balance. The DBRB algorithm is deployed on the head node of a cluster. It gathers the status from each cluster member and calculates their Node Importance Factors (NIFs) from the carried resources, residue power and compute capacity. The algorithm calculates the number of concurrent subtasks based on the deadlines, and allocates the subtasks to the lower NIFs first to balance the resources. The simulation results show that when cluster members carry multiple resources, resource are more balanced and rare resources serve longer in DBRB than in an Early Deadline First algorithm. We also analyze the resource balancing and average task finish time with different task deadline settings. And we show that the algorithm performs well in service isolation by serving multiple tasks with different deadlines. Moreover, the average task response time with various cluster size settings is well controlled within deadlines as well.","PeriodicalId":379382,"journal":{"name":"MILCOM 2013 - 2013 IEEE Military Communications Conference","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127704113","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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