Pub Date : 2015-11-01DOI: 10.1109/ALLERTON.2015.7447084
Sadra Sadraddini, C. Belta
Control synthesis from temporal logic specifications has gained popularity in recent years. In this paper, we use a model predictive approach to control discrete time linear systems with additive bounded disturbances subject to constraints given as formulas of signal temporal logic (STL). We introduce a (conservative) computationally efficient framework to synthesize control strategies based on mixed integer programs. The designed controllers satisfy the temporal logic requirements, are robust to all possible realizations of the disturbances, and optimal with respect to a cost function. In case the temporal logic constraint is infeasible, the controller satisfies a relaxed, minimally violating constraint. An illustrative case study is included.
{"title":"Robust temporal logic model predictive control","authors":"Sadra Sadraddini, C. Belta","doi":"10.1109/ALLERTON.2015.7447084","DOIUrl":"https://doi.org/10.1109/ALLERTON.2015.7447084","url":null,"abstract":"Control synthesis from temporal logic specifications has gained popularity in recent years. In this paper, we use a model predictive approach to control discrete time linear systems with additive bounded disturbances subject to constraints given as formulas of signal temporal logic (STL). We introduce a (conservative) computationally efficient framework to synthesize control strategies based on mixed integer programs. The designed controllers satisfy the temporal logic requirements, are robust to all possible realizations of the disturbances, and optimal with respect to a cost function. In case the temporal logic constraint is infeasible, the controller satisfies a relaxed, minimally violating constraint. An illustrative case study is included.","PeriodicalId":112948,"journal":{"name":"2015 53rd Annual Allerton Conference on Communication, Control, and Computing (Allerton)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120961138","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 : 2015-10-15DOI: 10.1109/ALLERTON.2015.7446992
Gauri Joshi, E. Soljanin, G. Wornell
In cloud computing systems, assigning a job to multiple servers and waiting for the earliest copy to finish is an effective method to combat the variability in response time of individual servers. Although adding redundant replicas always reduces service time, the total computing time spent per job may be higher, thus increasing waiting time in queue. The total time spent per job is also proportional to the cost of computing resources. We analyze how different redundancy strategies, for eg. number of replicas, and the time when they are issued and canceled, affect the latency and computing cost. We get the insight that the log-concavity of the service time distribution is a key factor in determining whether adding redundancy reduces latency and cost. If the service distribution is log-convex, then adding maximum redundancy reduces both latency and cost. And if it is log-concave, then having fewer replicas and canceling the redundant requests early is more effective.
{"title":"Efficient replication of queued tasks for latency reduction in cloud systems","authors":"Gauri Joshi, E. Soljanin, G. Wornell","doi":"10.1109/ALLERTON.2015.7446992","DOIUrl":"https://doi.org/10.1109/ALLERTON.2015.7446992","url":null,"abstract":"In cloud computing systems, assigning a job to multiple servers and waiting for the earliest copy to finish is an effective method to combat the variability in response time of individual servers. Although adding redundant replicas always reduces service time, the total computing time spent per job may be higher, thus increasing waiting time in queue. The total time spent per job is also proportional to the cost of computing resources. We analyze how different redundancy strategies, for eg. number of replicas, and the time when they are issued and canceled, affect the latency and computing cost. We get the insight that the log-concavity of the service time distribution is a key factor in determining whether adding redundancy reduces latency and cost. If the service distribution is log-convex, then adding maximum redundancy reduces both latency and cost. And if it is log-concave, then having fewer replicas and canceling the redundant requests early is more effective.","PeriodicalId":112948,"journal":{"name":"2015 53rd Annual Allerton Conference on Communication, Control, and Computing (Allerton)","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131110004","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 : 2015-10-14DOI: 10.1109/ALLERTON.2015.7447136
Xiugang Wu, Ayfer Özgür
The cut-set bound developed by Cover and El Gamal in 1979 has since remained the best known upper bound on the capacity of the Gaussian relay channel. We develop a new upper bound on the capacity of the Gaussian primitive relay channel which is tighter than the cut-set bound. Our proof is based on typicality arguments and concentration of Gaussian measure. Combined with a simple tensorization argument proposed by Courtade and Ozgur in 2015, our result also implies that the current capacity approximations for Gaussian relay networks, which have linear gap to the cut-set bound in the number of nodes, are order-optimal and leads to a lower bound on the preconstant.
{"title":"Cut-set bound is loose for Gaussian relay networks","authors":"Xiugang Wu, Ayfer Özgür","doi":"10.1109/ALLERTON.2015.7447136","DOIUrl":"https://doi.org/10.1109/ALLERTON.2015.7447136","url":null,"abstract":"The cut-set bound developed by Cover and El Gamal in 1979 has since remained the best known upper bound on the capacity of the Gaussian relay channel. We develop a new upper bound on the capacity of the Gaussian primitive relay channel which is tighter than the cut-set bound. Our proof is based on typicality arguments and concentration of Gaussian measure. Combined with a simple tensorization argument proposed by Courtade and Ozgur in 2015, our result also implies that the current capacity approximations for Gaussian relay networks, which have linear gap to the cut-set bound in the number of nodes, are order-optimal and leads to a lower bound on the preconstant.","PeriodicalId":112948,"journal":{"name":"2015 53rd Annual Allerton Conference on Communication, Control, and Computing (Allerton)","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116282070","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 : 2015-09-29DOI: 10.1109/ALLERTON.2015.7447017
T. Datta, Sheng Yang
Practical MIMO communication systems suffer performance loss from oscillator phase noise. In particular, if maximum likelihood (ML) detection is performed naively without considering the phase noise, it results in an error floor in its symbol error probability. In this paper, we propose a method to detect the correctness of the naive ML solution in the presence of strong phase noise. A criteria based on the ML cost differences between the ML solution and the actually transmitted vector is used to determine a set of possible candidate solutions. Next we propose a novel algorithm for data detection using phase noise estimation techniques to obtain an modified ML cost for each of the candidate solutions. This approach results in symbol error rate performance improvement by reducing the error floor without incurring much additional complexity due to phase noise estimation. Theoretical arguments as well as simulation studies are presented to support the performance improvement achieved.
实际的多输入多输出（MIMO）通信系统会因振荡器相位噪声而造成性能损失。特别是，如果在不考虑相位噪声的情况下进行最大似然（ML）检测，就会导致符号错误概率出现误差下限。在本文中，我们提出了一种在存在强相位噪声的情况下检测天真的 ML 解决方案正确性的方法。基于 ML 解法与实际传输向量之间的 ML 成本差异的标准被用来确定一组可能的候选解法。接下来，我们提出了一种利用相位噪声估计技术进行数据检测的新型算法，以获得每个候选解决方案的修正 ML 成本。这种方法通过降低误差底限来提高符号误差率性能，而不会因为相位噪声估计而增加很多复杂性。理论论证和仿真研究都支持所实现的性能改进。
{"title":"Improving MIMO detection performance in presence of phase noise using norm difference criterion","authors":"T. Datta, Sheng Yang","doi":"10.1109/ALLERTON.2015.7447017","DOIUrl":"https://doi.org/10.1109/ALLERTON.2015.7447017","url":null,"abstract":"Practical MIMO communication systems suffer performance loss from oscillator phase noise. In particular, if maximum likelihood (ML) detection is performed naively without considering the phase noise, it results in an error floor in its symbol error probability. In this paper, we propose a method to detect the correctness of the naive ML solution in the presence of strong phase noise. A criteria based on the ML cost differences between the ML solution and the actually transmitted vector is used to determine a set of possible candidate solutions. Next we propose a novel algorithm for data detection using phase noise estimation techniques to obtain an modified ML cost for each of the candidate solutions. This approach results in symbol error rate performance improvement by reducing the error floor without incurring much additional complexity due to phase noise estimation. Theoretical arguments as well as simulation studies are presented to support the performance improvement achieved.","PeriodicalId":112948,"journal":{"name":"2015 53rd Annual Allerton Conference on Communication, Control, and Computing (Allerton)","volume":"303 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131542647","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 : 2015-09-01DOI: 10.1109/ALLERTON.2015.7447115
Rahul Kidambi, Sreeram Kannan
The problem of estimating causal relationships from purely observational data is studied in this paper. We observe samples from a pair of random variables (X,Y) and wish to estimate whether X causes Y or Y causes X. Any joint distribution can be factored as pX,Y = pX pY|X = pY pX|Y and therefore the “causal” direction cannot be inferred from the joint distribution without further assumptions. In this paper, we propose and study the utility of Shannon capacity as a metric for causal directionality estimation. This opens up several open questions and directions for future study.
{"title":"On Shannon capacity and causal estimation","authors":"Rahul Kidambi, Sreeram Kannan","doi":"10.1109/ALLERTON.2015.7447115","DOIUrl":"https://doi.org/10.1109/ALLERTON.2015.7447115","url":null,"abstract":"The problem of estimating causal relationships from purely observational data is studied in this paper. We observe samples from a pair of random variables (X,Y) and wish to estimate whether X causes Y or Y causes X. Any joint distribution can be factored as p<sub>X,Y</sub> = p<sub>X</sub> p<sub>Y|X</sub> = p<sub>Y</sub> p<sub>X|Y</sub> and therefore the “causal” direction cannot be inferred from the joint distribution without further assumptions. In this paper, we propose and study the utility of Shannon capacity as a metric for causal directionality estimation. This opens up several open questions and directions for future study.","PeriodicalId":112948,"journal":{"name":"2015 53rd Annual Allerton Conference on Communication, Control, and Computing (Allerton)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115142606","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 : 2015-09-01DOI: 10.1109/ALLERTON.2015.7446986
Parinaz Naghizadeh Ardabili, M. Liu
We consider the provision of non-excludable public goods on a network of interdependent strategic users. We study three different equilibria of these games, namely the Nash equilibrium, socially optimal, and exit equilibrium profiles. We identify properties of the interdependence graph that guarantee the existence and uniqueness of these equilibria. We further establish a connection between users' centralities in their interdependence network, and their efforts at different interior equilibria of these games. These characterizations separate the effects of incoming and outgoing dependencies, as well as the influence of paths of different length, on users' effort levels. We discuss some conceptual and practical implications of this centrality-effort connection.
{"title":"Provision of non-excludable public goods on networks: From equilibrium to centrality measures","authors":"Parinaz Naghizadeh Ardabili, M. Liu","doi":"10.1109/ALLERTON.2015.7446986","DOIUrl":"https://doi.org/10.1109/ALLERTON.2015.7446986","url":null,"abstract":"We consider the provision of non-excludable public goods on a network of interdependent strategic users. We study three different equilibria of these games, namely the Nash equilibrium, socially optimal, and exit equilibrium profiles. We identify properties of the interdependence graph that guarantee the existence and uniqueness of these equilibria. We further establish a connection between users' centralities in their interdependence network, and their efforts at different interior equilibria of these games. These characterizations separate the effects of incoming and outgoing dependencies, as well as the influence of paths of different length, on users' effort levels. We discuss some conceptual and practical implications of this centrality-effort connection.","PeriodicalId":112948,"journal":{"name":"2015 53rd Annual Allerton Conference on Communication, Control, and Computing (Allerton)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115360791","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 : 2015-09-01DOI: 10.1109/ALLERTON.2015.7447116
Chung Chan, Tie Liu
This paper considers two mutual-information based approaches for clustering random variables proposed in the literature: clustering by mutual information relevance networks (MIRNs) and clustering by multivariate mutual information (MMI). Despite being two seemingly very different approaches, the derived clustering solutions share very strong structural similarity. Motivated by this curious fact, in this paper we show that there is a precise connection between these two clustering solutions via the celebrated Chow-Liu tree algorithm in machine learning: Under a Chow-Liu tree approximation to the underlying joint distribution, the clustering solutions provided by MIRNs and by MMI are, in fact, identical. This solidifies the heuristic view of clustering by MMI as a natural generalization of clustering by MIRNs from dependency-tree distributions to general joint distributions.
{"title":"Clustering by multivariate mutual information under Chow-Liu tree approximation","authors":"Chung Chan, Tie Liu","doi":"10.1109/ALLERTON.2015.7447116","DOIUrl":"https://doi.org/10.1109/ALLERTON.2015.7447116","url":null,"abstract":"This paper considers two mutual-information based approaches for clustering random variables proposed in the literature: clustering by mutual information relevance networks (MIRNs) and clustering by multivariate mutual information (MMI). Despite being two seemingly very different approaches, the derived clustering solutions share very strong structural similarity. Motivated by this curious fact, in this paper we show that there is a precise connection between these two clustering solutions via the celebrated Chow-Liu tree algorithm in machine learning: Under a Chow-Liu tree approximation to the underlying joint distribution, the clustering solutions provided by MIRNs and by MMI are, in fact, identical. This solidifies the heuristic view of clustering by MMI as a natural generalization of clustering by MIRNs from dependency-tree distributions to general joint distributions.","PeriodicalId":112948,"journal":{"name":"2015 53rd Annual Allerton Conference on Communication, Control, and Computing (Allerton)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115384013","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 : 2015-09-01DOI: 10.1109/ALLERTON.2015.7447119
Víctor Valls, D. Leith
We consider the subgradient method for the dual problem in convex optimisation with approximate multipliers, i.e., the subgradient used in the update of the dual variables is obtained using an approximation of the true Lagrange multipliers. This problem is interesting for optimisation problems where the exact Lagrange multipliers might not be readily accessible. For example, in distributed optimisation the exact Lagrange multipliers might not be available at the nodes due to communication delays or losses. We show that we can construct approximate primal solutions that can get arbitrarily close to the set of optima as step size α is reduced. Applications of the analysis include unsynchronised subgradient updates in the dual variable update and unsynchronised max-weight scheduling.
{"title":"Dual subgradient methods using approximate multipliers","authors":"Víctor Valls, D. Leith","doi":"10.1109/ALLERTON.2015.7447119","DOIUrl":"https://doi.org/10.1109/ALLERTON.2015.7447119","url":null,"abstract":"We consider the subgradient method for the dual problem in convex optimisation with approximate multipliers, i.e., the subgradient used in the update of the dual variables is obtained using an approximation of the true Lagrange multipliers. This problem is interesting for optimisation problems where the exact Lagrange multipliers might not be readily accessible. For example, in distributed optimisation the exact Lagrange multipliers might not be available at the nodes due to communication delays or losses. We show that we can construct approximate primal solutions that can get arbitrarily close to the set of optima as step size α is reduced. Applications of the analysis include unsynchronised subgradient updates in the dual variable update and unsynchronised max-weight scheduling.","PeriodicalId":112948,"journal":{"name":"2015 53rd Annual Allerton Conference on Communication, Control, and Computing (Allerton)","volume":"167 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123081229","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 : 2015-09-01DOI: 10.1109/ALLERTON.2015.7447171
D. Thanou, P. Frossard
We study the distributed processing of graph signals that are well represented by graph spectral dictionaries. We first analyze the impact of quantization noise in the distributed computation of polynomial dictionary operators that are commonly used in various signal processing tasks. We show that the impact of quantization depends on the graph geometry and on the structure of the spectral dictionaries. Then, we focus on the problem of distributed sparse signal representation that can be solved with an iterative soft thresholding algorithm. We define conditions on the dictionary structure to ensure the convergence of the distributed algorithm and finally propose a dictionary learning solution that permits to control the robustness to quantization noise. Experimental results for reconstruction and denoising of both synthetic and practical signals illustrate the tradeoffs that exist between accurate signal representation and robustness to quantization error in the design of dictionaries operators in distributed graph signal processing.
{"title":"Distributed signal processing with graph spectral dictionaries","authors":"D. Thanou, P. Frossard","doi":"10.1109/ALLERTON.2015.7447171","DOIUrl":"https://doi.org/10.1109/ALLERTON.2015.7447171","url":null,"abstract":"We study the distributed processing of graph signals that are well represented by graph spectral dictionaries. We first analyze the impact of quantization noise in the distributed computation of polynomial dictionary operators that are commonly used in various signal processing tasks. We show that the impact of quantization depends on the graph geometry and on the structure of the spectral dictionaries. Then, we focus on the problem of distributed sparse signal representation that can be solved with an iterative soft thresholding algorithm. We define conditions on the dictionary structure to ensure the convergence of the distributed algorithm and finally propose a dictionary learning solution that permits to control the robustness to quantization noise. Experimental results for reconstruction and denoising of both synthetic and practical signals illustrate the tradeoffs that exist between accurate signal representation and robustness to quantization error in the design of dictionaries operators in distributed graph signal processing.","PeriodicalId":112948,"journal":{"name":"2015 53rd Annual Allerton Conference on Communication, Control, and Computing (Allerton)","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127477847","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 : 2015-09-01DOI: 10.1109/ALLERTON.2015.7447004
M. G. Martinez, Jialin Liu, Bowen Li, J. Mathieu, C. Anderson
The steady rise of electricity demand and renewable energy sources is increasing the need for flexibility to enable power systems to adapt to changes in supply and demand. To this end, demand response programs have the potential to increase the flexibility of the system. In this work, a direct-load-control demand response program is used in the scheduling task of a power system with high levels of variable renewable generation. The model considers different classes of reserves provided by both conventional generation and responsive demand. Unit commitment, generator dispatch and reserve allocations are determined with appropriate risk-averse levels to guarantee a reliable and feasible operation of the system across the planning horizon. Risk preferences are reflected in constraint satisfaction via robust and probabilistically-constrained approaches. Case studies with a 57-bus system show that the probabilistic approach allows higher wind share in the power network and incurs lower costs than the robust approach. In addition, results show that controllable loads are an important contributor to system flexibility, though addition of other classes of responsive demand will also bring desirable flexibility.
{"title":"Enabling renewable resource integration: The balance between robustness and flexibility","authors":"M. G. Martinez, Jialin Liu, Bowen Li, J. Mathieu, C. Anderson","doi":"10.1109/ALLERTON.2015.7447004","DOIUrl":"https://doi.org/10.1109/ALLERTON.2015.7447004","url":null,"abstract":"The steady rise of electricity demand and renewable energy sources is increasing the need for flexibility to enable power systems to adapt to changes in supply and demand. To this end, demand response programs have the potential to increase the flexibility of the system. In this work, a direct-load-control demand response program is used in the scheduling task of a power system with high levels of variable renewable generation. The model considers different classes of reserves provided by both conventional generation and responsive demand. Unit commitment, generator dispatch and reserve allocations are determined with appropriate risk-averse levels to guarantee a reliable and feasible operation of the system across the planning horizon. Risk preferences are reflected in constraint satisfaction via robust and probabilistically-constrained approaches. Case studies with a 57-bus system show that the probabilistic approach allows higher wind share in the power network and incurs lower costs than the robust approach. In addition, results show that controllable loads are an important contributor to system flexibility, though addition of other classes of responsive demand will also bring desirable flexibility.","PeriodicalId":112948,"journal":{"name":"2015 53rd Annual Allerton Conference on Communication, Control, and Computing (Allerton)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123286382","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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