Pub Date : 2018-02-01DOI: 10.1109/NCC.2018.8599992
Priyanka Maity, Siddharth Deshmukh
In this paper, we investigate a double threshold based cooperative spectrum sensing scenario. Our objective is to determine the optimal threshold for majority rule which must be selected for minimum error in final decision. The CR sensors are assumed to make local hard decisions based on conventional energy detection technique and communicate one bit decision information to the fusion center. Here we assume that sensors whose test statistics fall in ambiguity region do not report to the fusion center. A majority rule is applied at the fusion center in which at least threshold $n$* number of local sensor decision must favor for presence of primary user (PU) to make the final decision on presence of PU. Since choice of $n$* decides error in final decision, we formulate an expression to compute optimal value $n$*, i.e., n*opt which minimizes error in final decision. Further, due to uncertainty in number of sensors with test statistics in ambiguity region, the threshold n*opt also becomes a random variable. Hence we derive a statistical model to characterize the density function of number of sensors with test statistics in ambiguity region, and later exploit it to derive an expression for expected value of n*opt. Our simulation results validate our approach in which we show by selecting n*opt as threshold for majority rule, the error in final decision is at its minimum value.
{"title":"Optimization of Majority Rule Threshold in Double Threshold Based Cooperative Cognitive Radio Network","authors":"Priyanka Maity, Siddharth Deshmukh","doi":"10.1109/NCC.2018.8599992","DOIUrl":"https://doi.org/10.1109/NCC.2018.8599992","url":null,"abstract":"In this paper, we investigate a double threshold based cooperative spectrum sensing scenario. Our objective is to determine the optimal threshold for majority rule which must be selected for minimum error in final decision. The CR sensors are assumed to make local hard decisions based on conventional energy detection technique and communicate one bit decision information to the fusion center. Here we assume that sensors whose test statistics fall in ambiguity region do not report to the fusion center. A majority rule is applied at the fusion center in which at least threshold $n$* number of local sensor decision must favor for presence of primary user (PU) to make the final decision on presence of PU. Since choice of $n$* decides error in final decision, we formulate an expression to compute optimal value $n$*, i.e., n*opt which minimizes error in final decision. Further, due to uncertainty in number of sensors with test statistics in ambiguity region, the threshold n*opt also becomes a random variable. Hence we derive a statistical model to characterize the density function of number of sensors with test statistics in ambiguity region, and later exploit it to derive an expression for expected value of n*opt. Our simulation results validate our approach in which we show by selecting n*opt as threshold for majority rule, the error in final decision is at its minimum value.","PeriodicalId":121544,"journal":{"name":"2018 Twenty Fourth National Conference on Communications (NCC)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121056724","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 : 2018-02-01DOI: 10.1109/NCC.2018.8600212
S. Saurabh, A. Sairam
IP source spoofing is a consequence of lack of packet level authentication in the Internet which allows attackers to carry out Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks. Source address validation filtering is one of the most important scheme that is deployed in the Internet to deter such attacks by filtering the spoofed IP packets. In this paper, we propose a novel scheme to study the deployment of source address validation-filtering by using some special path backscatter messages that are generated by the spoofed traffic. We use the long term absence of such messages from an Autonomous System (AS) to classify it as non-spoofer AS. We use Caida's backscatter dataset for our study. We provide the list of spoofer and non-spoofer ASes from the given dataset. We also provide detailed mathematical analysis for calculating the amount of time we need to wait before declaring an AS as a non-spoofer. Besides, we use the normal approximation of binomial distribution to calculate confidence interval for the proportion of ASes allowing spoofing and to test the hypothesis regarding the spoofing activity in the Internet.
{"title":"Inferring the Deployment of Source Address Validation Filtering using Silence of Path-Backscatter","authors":"S. Saurabh, A. Sairam","doi":"10.1109/NCC.2018.8600212","DOIUrl":"https://doi.org/10.1109/NCC.2018.8600212","url":null,"abstract":"IP source spoofing is a consequence of lack of packet level authentication in the Internet which allows attackers to carry out Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks. Source address validation filtering is one of the most important scheme that is deployed in the Internet to deter such attacks by filtering the spoofed IP packets. In this paper, we propose a novel scheme to study the deployment of source address validation-filtering by using some special path backscatter messages that are generated by the spoofed traffic. We use the long term absence of such messages from an Autonomous System (AS) to classify it as non-spoofer AS. We use Caida's backscatter dataset for our study. We provide the list of spoofer and non-spoofer ASes from the given dataset. We also provide detailed mathematical analysis for calculating the amount of time we need to wait before declaring an AS as a non-spoofer. Besides, we use the normal approximation of binomial distribution to calculate confidence interval for the proportion of ASes allowing spoofing and to test the hypothesis regarding the spoofing activity in the Internet.","PeriodicalId":121544,"journal":{"name":"2018 Twenty Fourth National Conference on Communications (NCC)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128451156","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 : 2018-02-01DOI: 10.1109/NCC.2018.8600115
Arijit Dutta, S. Vijayakumaran
In this paper, we have found all possible largest permutation codes in S4and S5under Kendall T-distance. We consider two rewrite operations namely push-to-the-top and minimal-push-up and give the optimum codes in terms of rewrite cost for both these techniques. These optimum codes can be obtained from a set of relatively smaller size for both the cases. We also give the largest single error correcting Gray code when minimal-push-up is used.
在Kendall t -距离下，我们找到了s4和s55中所有可能的最大排列码。我们考虑了两种重写操作，即push-to- top和minimum -push-up，并根据这两种技术的重写成本给出了最佳代码。对于这两种情况，都可以从一个相对较小的码集中得到这些最优码。当使用最小俯卧撑时，我们也给出了最大的单次纠错格雷码。
{"title":"Rewrite Cost optimal Rank Modulation Codes in S4 and S5","authors":"Arijit Dutta, S. Vijayakumaran","doi":"10.1109/NCC.2018.8600115","DOIUrl":"https://doi.org/10.1109/NCC.2018.8600115","url":null,"abstract":"In this paper, we have found all possible largest permutation codes in S4and S5under Kendall T-distance. We consider two rewrite operations namely push-to-the-top and minimal-push-up and give the optimum codes in terms of rewrite cost for both these techniques. These optimum codes can be obtained from a set of relatively smaller size for both the cases. We also give the largest single error correcting Gray code when minimal-push-up is used.","PeriodicalId":121544,"journal":{"name":"2018 Twenty Fourth National Conference on Communications (NCC)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116373449","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 : 2018-02-01DOI: 10.1109/NCC.2018.8600030
Santosh Fatale, Sri Prakash, Sharayu Moharir
This work focuses on designing caching policies for transient data, i.e., data which can be used to serve requests only for a finite duration of time after which it becomes redundant. We first characterize the fundamental limit on the performance of caching policies for transient data and characterize the performance of traditional caching policies like LRU for this setting. Traditional caching policies often make decisions based on the popularity of the data being cached. We propose a new caching policy which uses both the popularity and the residual lifetime (time remaining before the data becomes redundant) to make caching decisions. We show that in the setting where data being cached is transient, our policy outperforms traditional caching policies.
{"title":"Caching Policies for Transient Data","authors":"Santosh Fatale, Sri Prakash, Sharayu Moharir","doi":"10.1109/NCC.2018.8600030","DOIUrl":"https://doi.org/10.1109/NCC.2018.8600030","url":null,"abstract":"This work focuses on designing caching policies for transient data, i.e., data which can be used to serve requests only for a finite duration of time after which it becomes redundant. We first characterize the fundamental limit on the performance of caching policies for transient data and characterize the performance of traditional caching policies like LRU for this setting. Traditional caching policies often make decisions based on the popularity of the data being cached. We propose a new caching policy which uses both the popularity and the residual lifetime (time remaining before the data becomes redundant) to make caching decisions. We show that in the setting where data being cached is transient, our policy outperforms traditional caching policies.","PeriodicalId":121544,"journal":{"name":"2018 Twenty Fourth National Conference on Communications (NCC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114489232","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 : 2018-02-01DOI: 10.1109/NCC.2018.8600087
Muralikrishnna G. Sethuraman, Sooraj K. Ambat, K. Hari
Compressed sensing (CS) is a sampling paradigm that enables sampling signals at sub Nyquist rates by exploiting the sparse nature of signals. One of the main concerns in CS is the reconstruction of the signal after sampling. Many reconstruction algorithms have been proposed in the literature for the recovery of the sparse signals - Basis Pursuit, Orthogonal Matching Pursuit (OMP), Look Ahead Orthogonal Matching Pursuit (LAOMP) are some of the popular reconstruction algorithms. LAOMP, a modification of OMP, improves the reconstruction accuracy of OMP by employing a look ahead procedure. But LAOMP suffers from the drawback of being very expensive in terms of the computational time. In this paper we propose a modified version of the LAOMP algorithm called Batch-LAOMP which has a lesser computational complexity and also gives better performance in terms of reconstruction accuracy as seen from the results of the numerical experiments.
{"title":"Batch Look Ahead Orthogonal Matching Pursuit","authors":"Muralikrishnna G. Sethuraman, Sooraj K. Ambat, K. Hari","doi":"10.1109/NCC.2018.8600087","DOIUrl":"https://doi.org/10.1109/NCC.2018.8600087","url":null,"abstract":"Compressed sensing (CS) is a sampling paradigm that enables sampling signals at sub Nyquist rates by exploiting the sparse nature of signals. One of the main concerns in CS is the reconstruction of the signal after sampling. Many reconstruction algorithms have been proposed in the literature for the recovery of the sparse signals - Basis Pursuit, Orthogonal Matching Pursuit (OMP), Look Ahead Orthogonal Matching Pursuit (LAOMP) are some of the popular reconstruction algorithms. LAOMP, a modification of OMP, improves the reconstruction accuracy of OMP by employing a look ahead procedure. But LAOMP suffers from the drawback of being very expensive in terms of the computational time. In this paper we propose a modified version of the LAOMP algorithm called Batch-LAOMP which has a lesser computational complexity and also gives better performance in terms of reconstruction accuracy as seen from the results of the numerical experiments.","PeriodicalId":121544,"journal":{"name":"2018 Twenty Fourth National Conference on Communications (NCC)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121956041","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 : 2018-02-01DOI: 10.1109/NCC.2018.8599972
P. Vs, Jiji Charangatt Victor
3D reconstruction of underwater objects is a challenging problem in computer vision due to the scattering and absorption of light which leads to contrast and colour degradations of the acquired images. In addition, refraction across media boundaries introduces geometric variations which lead to erroneous correspondence matching between images. In this paper, we present a refraction reconstruction model to compensate for refractive errors. Our model is for images acquired with the camera above the water surface instead of underwater camera images, excluding the possible refraction across glass-water interface. The corrected images are used under a multi-view 3D reconstruction framework to produce the 3D geometry of the underwater objects as well as camera pose.
{"title":"Multiview 3D Reconstruction of Underwater Scenes Acquired With a Single Refractive Layer Using Structure from Motion","authors":"P. Vs, Jiji Charangatt Victor","doi":"10.1109/NCC.2018.8599972","DOIUrl":"https://doi.org/10.1109/NCC.2018.8599972","url":null,"abstract":"3D reconstruction of underwater objects is a challenging problem in computer vision due to the scattering and absorption of light which leads to contrast and colour degradations of the acquired images. In addition, refraction across media boundaries introduces geometric variations which lead to erroneous correspondence matching between images. In this paper, we present a refraction reconstruction model to compensate for refractive errors. Our model is for images acquired with the camera above the water surface instead of underwater camera images, excluding the possible refraction across glass-water interface. The corrected images are used under a multi-view 3D reconstruction framework to produce the 3D geometry of the underwater objects as well as camera pose.","PeriodicalId":121544,"journal":{"name":"2018 Twenty Fourth National Conference on Communications (NCC)","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121755341","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 : 2018-02-01DOI: 10.1109/NCC.2018.8599975
R. R, U. Mukherji
We propose a novel recursive algorithm for determining the optimal admission and transmission rates for an M/M/1 transmitter buffer for obtaining minimum average queue length, under quasi-static fading, while satisfying a throughput constraint with given available transmit power. The optimal rate setting policy is obtained with significant savings in memory and computational complexity, and is simple and easy to implement.
{"title":"Optimal rate control in a quasi-static wireless fading channel with throughput and power constraints","authors":"R. R, U. Mukherji","doi":"10.1109/NCC.2018.8599975","DOIUrl":"https://doi.org/10.1109/NCC.2018.8599975","url":null,"abstract":"We propose a novel recursive algorithm for determining the optimal admission and transmission rates for an M/M/1 transmitter buffer for obtaining minimum average queue length, under quasi-static fading, while satisfying a throughput constraint with given available transmit power. The optimal rate setting policy is obtained with significant savings in memory and computational complexity, and is simple and easy to implement.","PeriodicalId":121544,"journal":{"name":"2018 Twenty Fourth National Conference on Communications (NCC)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123179883","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 : 2018-02-01DOI: 10.1109/NCC.2018.8600153
Alok Kumar, A. R. Pais
Wireless sensor networks are susceptible to report fabrication attacks, where adversary can use compromised nodes to flood the network with false reports. En-route filtering is a mechanism of dropping bogus/false reports while they are being forwarded towards the sink. Majority of the proposed en-route filtering schemes are probabilistic, where the originality of forwarded reports is checked with fixed probability by intermediate nodes. Thus, false reports can travel multiple hops before being dropped in probabilistic en-route filtering schemes. Few deterministic based en-route filtering schemes have also been proposed, but all such schemes need to send the reports through fixed paths. To overcome the above mentioned limitations of existing en-route filtering schemes, we propose a novel deterministic enroute filtering scheme. In the proposed scheme, secret keys are allocated to sensor nodes based on combinatorial design. Such design ensures direct communication between any two nodes without adding more key storage overhead. We provide in-depth analysis for the proposed scheme. The proposed scheme significantly outperforms existing schemes in terms of expected filtering position of false reports and is more buoyant to selective forwarding and report disruption attacks. Our scheme also performs neck-to-neck with existing schemes in terms of protocol overheads.
{"title":"A New Combinatorial Design Based Data En-Route Filtering Scheme for Wireless Sensor Networks","authors":"Alok Kumar, A. R. Pais","doi":"10.1109/NCC.2018.8600153","DOIUrl":"https://doi.org/10.1109/NCC.2018.8600153","url":null,"abstract":"Wireless sensor networks are susceptible to report fabrication attacks, where adversary can use compromised nodes to flood the network with false reports. En-route filtering is a mechanism of dropping bogus/false reports while they are being forwarded towards the sink. Majority of the proposed en-route filtering schemes are probabilistic, where the originality of forwarded reports is checked with fixed probability by intermediate nodes. Thus, false reports can travel multiple hops before being dropped in probabilistic en-route filtering schemes. Few deterministic based en-route filtering schemes have also been proposed, but all such schemes need to send the reports through fixed paths. To overcome the above mentioned limitations of existing en-route filtering schemes, we propose a novel deterministic enroute filtering scheme. In the proposed scheme, secret keys are allocated to sensor nodes based on combinatorial design. Such design ensures direct communication between any two nodes without adding more key storage overhead. We provide in-depth analysis for the proposed scheme. The proposed scheme significantly outperforms existing schemes in terms of expected filtering position of false reports and is more buoyant to selective forwarding and report disruption attacks. Our scheme also performs neck-to-neck with existing schemes in terms of protocol overheads.","PeriodicalId":121544,"journal":{"name":"2018 Twenty Fourth National Conference on Communications (NCC)","volume":"7 Sup2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128290335","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 : 2018-02-01DOI: 10.1109/NCC.2018.8600191
V. Sukumaran
We consider wireless downlinks where the base station dynamically switches between different users in order to transmit data intended for the respective users. When the base station switches from serving one user to another, there is a reconfiguration delay. For such wireless downlinks with reconfiguration delay we consider the problem of throughput optimal scheduling. We propose the 1-lookahead scheduling policy and analytically show that it is throughput optimal. We obtain the 1-lookahead policy by using an approximate solution to a Markov decision process formulation of the scheduling problem. The approximate solution is also used to explain the biased maxweight form of 1-lookahead as well as an existing policy.
{"title":"Throughput Optimal Scheduling for Wireless Downlinks with Reconfiguration Delay","authors":"V. Sukumaran","doi":"10.1109/NCC.2018.8600191","DOIUrl":"https://doi.org/10.1109/NCC.2018.8600191","url":null,"abstract":"We consider wireless downlinks where the base station dynamically switches between different users in order to transmit data intended for the respective users. When the base station switches from serving one user to another, there is a reconfiguration delay. For such wireless downlinks with reconfiguration delay we consider the problem of throughput optimal scheduling. We propose the 1-lookahead scheduling policy and analytically show that it is throughput optimal. We obtain the 1-lookahead policy by using an approximate solution to a Markov decision process formulation of the scheduling problem. The approximate solution is also used to explain the biased maxweight form of 1-lookahead as well as an existing policy.","PeriodicalId":121544,"journal":{"name":"2018 Twenty Fourth National Conference on Communications (NCC)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128382740","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 : 2018-02-01DOI: 10.1109/NCC.2018.8600049
Manan Jani, Parul Gargt, Akash Gupta
In this paper, a novel dual hop Decode-and-Forward (DF) relay assisted deeply integrated Power Line Communications (PLC) - Visible Light Communications (VLC) system is proposed. The PLC link is assumed to be affected by Log-Normal fading and additive background and impulsive noises whereas the channel characteristics of the VLC link are analyzed statistically as a function of the randomness of the position of the end users. In this study, novel closed form expressions of the cumulative distribution function (CDF) of the equivalent end to end signal-to-noise ratio (SNR) are derived. Also, we analyze the performance of the system in terms of the user outage probability to maintain Quality of Service (QoS).
{"title":"Modeling and Outage Analysis of DF Relay assisted mixed PLC-VLC System","authors":"Manan Jani, Parul Gargt, Akash Gupta","doi":"10.1109/NCC.2018.8600049","DOIUrl":"https://doi.org/10.1109/NCC.2018.8600049","url":null,"abstract":"In this paper, a novel dual hop Decode-and-Forward (DF) relay assisted deeply integrated Power Line Communications (PLC) - Visible Light Communications (VLC) system is proposed. The PLC link is assumed to be affected by Log-Normal fading and additive background and impulsive noises whereas the channel characteristics of the VLC link are analyzed statistically as a function of the randomness of the position of the end users. In this study, novel closed form expressions of the cumulative distribution function (CDF) of the equivalent end to end signal-to-noise ratio (SNR) are derived. Also, we analyze the performance of the system in terms of the user outage probability to maintain Quality of Service (QoS).","PeriodicalId":121544,"journal":{"name":"2018 Twenty Fourth National Conference on Communications (NCC)","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121106190","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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