Pub Date : 2013-12-09DOI: 10.1109/LatinCloud.2013.6842223
A. Toueir, J. Broisin, M. Sibilla
We argue in this paper that autonomic systems need to make their integrated monitoring adaptive in order to improve their “comprehensive” Quality of Service (QoS). We propose to design this adaptation based on high level objectives (called goals) related to the management of both the “functional system QoS” and the “monitoring system QoS”. Starting from some previous works suggesting a model-driven adaptable monitoring framework composed of 3 layers (configurability, adaptability, governability), we introduce a methodology to identify the functional and monitoring high level goals (according to the agreed Service Level Agreement - SLA) in order to drive models' instantiation. This proposal is first applied to a cloud provider case study for which two high level goals are developed (respect metrics freshness and minimize monitoring cost), and then simulated to show how the quality of management decisions, as well as intelligent monitoring of dynamic SLA, could be improved.
{"title":"A goal-oriented approach for adaptive SLA monitoring: A cloud provider case study","authors":"A. Toueir, J. Broisin, M. Sibilla","doi":"10.1109/LatinCloud.2013.6842223","DOIUrl":"https://doi.org/10.1109/LatinCloud.2013.6842223","url":null,"abstract":"We argue in this paper that autonomic systems need to make their integrated monitoring adaptive in order to improve their “comprehensive” Quality of Service (QoS). We propose to design this adaptation based on high level objectives (called goals) related to the management of both the “functional system QoS” and the “monitoring system QoS”. Starting from some previous works suggesting a model-driven adaptable monitoring framework composed of 3 layers (configurability, adaptability, governability), we introduce a methodology to identify the functional and monitoring high level goals (according to the agreed Service Level Agreement - SLA) in order to drive models' instantiation. This proposal is first applied to a cloud provider case study for which two high level goals are developed (respect metrics freshness and minimize monitoring cost), and then simulated to show how the quality of management decisions, as well as intelligent monitoring of dynamic SLA, could be improved.","PeriodicalId":344490,"journal":{"name":"2nd IEEE Latin American Conference on Cloud Computing and Communications","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123299144","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 : 2013-12-01DOI: 10.1109/LatinCloud.2013.6842214
E. Coutinho, D. Gomes, J. Souza
Elasticity is a key feature of cloud computing. Its application has become an increasing need due to the dynamic nature of different applications and different workloads imposed by them. This article aims to analyze the behavior of the elasticity in a cloud computing environment, based on some metrics related to response time of allocation operations and used resources in a cloud computing environment. A proposal of seven metrics for evaluation of the elasticity is presented. An experiment to validate the proposal and analysis of elasticity in a cloud computing environment is described with microbenchmarks and a scientific application. At the end, a discussion of the results and future work.
{"title":"An analysis of elasticity in cloud computing environments based on allocation time and resources","authors":"E. Coutinho, D. Gomes, J. Souza","doi":"10.1109/LatinCloud.2013.6842214","DOIUrl":"https://doi.org/10.1109/LatinCloud.2013.6842214","url":null,"abstract":"Elasticity is a key feature of cloud computing. Its application has become an increasing need due to the dynamic nature of different applications and different workloads imposed by them. This article aims to analyze the behavior of the elasticity in a cloud computing environment, based on some metrics related to response time of allocation operations and used resources in a cloud computing environment. A proposal of seven metrics for evaluation of the elasticity is presented. An experiment to validate the proposal and analysis of elasticity in a cloud computing environment is described with microbenchmarks and a scientific application. At the end, a discussion of the results and future work.","PeriodicalId":344490,"journal":{"name":"2nd IEEE Latin American Conference on Cloud Computing and Communications","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132262300","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 : 2013-12-01DOI: 10.1109/LatinCloud.2013.6842220
Gustavo Alves, Everton Cavalcante, Frederico Lopes, Ernani Azevedo, R. Dantas, T. Batista, S. Fernandes, C. Kamienski
In this paper we present a new architecture for the Cloud Integrator platform that extends it in two directions. The first one aimed at improving the way of an application can be defined by a developer. Instead of dealing with the burden of defining applications only by specifying semantic workflows in terms of activities expressed as a tuple <;task, object>, a developer can rely on the definition of complete executions flows or partial execution flows. The second extension aimed at the automatic deployment of applications in a cloud platform, thus allowing the simultaneous use of it by several clients over the Internet. We also present a proof-of-concept that illustrates the use of the cloud-based platform in a flight booking application.
{"title":"Tasks meet flows: Merging two paradigms in a Cloud applications development platform","authors":"Gustavo Alves, Everton Cavalcante, Frederico Lopes, Ernani Azevedo, R. Dantas, T. Batista, S. Fernandes, C. Kamienski","doi":"10.1109/LatinCloud.2013.6842220","DOIUrl":"https://doi.org/10.1109/LatinCloud.2013.6842220","url":null,"abstract":"In this paper we present a new architecture for the Cloud Integrator platform that extends it in two directions. The first one aimed at improving the way of an application can be defined by a developer. Instead of dealing with the burden of defining applications only by specifying semantic workflows in terms of activities expressed as a tuple <;task, object>, a developer can rely on the definition of complete executions flows or partial execution flows. The second extension aimed at the automatic deployment of applications in a cloud platform, thus allowing the simultaneous use of it by several clients over the Internet. We also present a proof-of-concept that illustrates the use of the cloud-based platform in a flight booking application.","PeriodicalId":344490,"journal":{"name":"2nd IEEE Latin American Conference on Cloud Computing and Communications","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134350937","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 : 2013-12-01DOI: 10.1109/LatinCloud.2013.6842217
A. Barros, Andrey Brito, F. Brasileiro, Marcos Nobrega
From the perspective of a typical cloud user, clouds are a source of unlimited computational resources that can be contracted as needed. As a consequence, users are relieved from the task of planning the capacity of their infrastructure. In practice, the problem of capacity planning has simply shifted from the cloud users to the cloud providers. The main challenge of cloud providers is, therefore, to reduce as much as possible the idleness of their infrastructure, at the same time that they appropriately support their variable workload. One approach used by public cloud providers to reduce the infrastructure idleness is to offer resources with a degraded quality of service. However, in private clouds, the idea of exploiting idle capacity has been little explored. In this demo, we present a system that opportunistically explores idle capacity in private cloud providers. The best effort service provided by resources exploited opportunistically can be efficiently used by users that need to run bag-of-task jobs as fast as possible-a workload that is becoming more and more common nowadays.
{"title":"Optimizing resource utilization in private clouds with an opportunistic approach","authors":"A. Barros, Andrey Brito, F. Brasileiro, Marcos Nobrega","doi":"10.1109/LatinCloud.2013.6842217","DOIUrl":"https://doi.org/10.1109/LatinCloud.2013.6842217","url":null,"abstract":"From the perspective of a typical cloud user, clouds are a source of unlimited computational resources that can be contracted as needed. As a consequence, users are relieved from the task of planning the capacity of their infrastructure. In practice, the problem of capacity planning has simply shifted from the cloud users to the cloud providers. The main challenge of cloud providers is, therefore, to reduce as much as possible the idleness of their infrastructure, at the same time that they appropriately support their variable workload. One approach used by public cloud providers to reduce the infrastructure idleness is to offer resources with a degraded quality of service. However, in private clouds, the idea of exploiting idle capacity has been little explored. In this demo, we present a system that opportunistically explores idle capacity in private cloud providers. The best effort service provided by resources exploited opportunistically can be efficiently used by users that need to run bag-of-task jobs as fast as possible-a workload that is becoming more and more common nowadays.","PeriodicalId":344490,"journal":{"name":"2nd IEEE Latin American Conference on Cloud Computing and Communications","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125450471","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 : 2013-12-01DOI: 10.1109/LatinCloud.2013.6842215
P. Endo, M. S. Batista, G. Gonçalves, Moisés Rodrigues, D. Sadok, J. Kelner, A. Sefidcon, F. Wuhib
Due to the growth of Cloud Computing, the supporting infrastructure has become more complex, and the centralized solutions suffer resource management difficulties due to the large scale and the dynamicity of the scenario. Consequently, distributed solutions have been proposed in the literature and the self-organizing ones have attracted particular interest due to their robustness and adaptability characteristics. Techniques, such as bio-inspired computing, multi-agent systems, and evolutionary techniques are used to manage resources. The main goal of this paper is to present a start study about how self-organizing solutions are applied in resource management of Cloud providers, as well as to highlight the main research challenges in this area.
{"title":"Self-organizing strategies for resource management in Cloud Computing: State-of-the-art and challenges","authors":"P. Endo, M. S. Batista, G. Gonçalves, Moisés Rodrigues, D. Sadok, J. Kelner, A. Sefidcon, F. Wuhib","doi":"10.1109/LatinCloud.2013.6842215","DOIUrl":"https://doi.org/10.1109/LatinCloud.2013.6842215","url":null,"abstract":"Due to the growth of Cloud Computing, the supporting infrastructure has become more complex, and the centralized solutions suffer resource management difficulties due to the large scale and the dynamicity of the scenario. Consequently, distributed solutions have been proposed in the literature and the self-organizing ones have attracted particular interest due to their robustness and adaptability characteristics. Techniques, such as bio-inspired computing, multi-agent systems, and evolutionary techniques are used to manage resources. The main goal of this paper is to present a start study about how self-organizing solutions are applied in resource management of Cloud providers, as well as to highlight the main research challenges in this area.","PeriodicalId":344490,"journal":{"name":"2nd IEEE Latin American Conference on Cloud Computing and Communications","volume":"123 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117324839","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 : 2013-12-01DOI: 10.1109/LatinCloud.2013.6842219
Daniel S. Marcon, L. Bittencourt, R. Dantas, M. Neves, E. Madeira, S. Fernandes, C. Kamienski, M. Barcellos, L. Gaspary, N. Fonseca
Hybrid cloud management must deal with resources from both public and private clouds, as well as their interaction. When workflows are executed in a hybrid cloud, dependencies among their components bring new factors to be considered during specification, scheduling, and virtual machine provisioning. In this paper, we describe three components, namely workflow code, scheduler, and resource allocator, which enable the specification and execution of workflows in hybrid clouds in the context of the AltoStratus middleware. We present a case study that shows the interaction among these components, and their applicability in practice.
{"title":"Workflow specification and scheduling with security constraints in hybrid clouds","authors":"Daniel S. Marcon, L. Bittencourt, R. Dantas, M. Neves, E. Madeira, S. Fernandes, C. Kamienski, M. Barcellos, L. Gaspary, N. Fonseca","doi":"10.1109/LatinCloud.2013.6842219","DOIUrl":"https://doi.org/10.1109/LatinCloud.2013.6842219","url":null,"abstract":"Hybrid cloud management must deal with resources from both public and private clouds, as well as their interaction. When workflows are executed in a hybrid cloud, dependencies among their components bring new factors to be considered during specification, scheduling, and virtual machine provisioning. In this paper, we describe three components, namely workflow code, scheduler, and resource allocator, which enable the specification and execution of workflows in hybrid clouds in the context of the AltoStratus middleware. We present a case study that shows the interaction among these components, and their applicability in practice.","PeriodicalId":344490,"journal":{"name":"2nd IEEE Latin American Conference on Cloud Computing and Communications","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123649949","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 : 2013-12-01DOI: 10.1109/LatinCloud.2013.6842213
R. Gomes, F. Costa, N. Bencomo
Specification of the non-functional requirements of applications and determining the required resources for their execution are activities that demand a great deal of technical knowledge, frequently resulting in an inefficient use of resources. Cloud computing is an alternative for provisioning of resources, which can be done using either the provider's own infrastructure or the infrastructure of one or more public clouds, or even a combination of both. It enables more flexibly/elastic use of resources, but does not solve the specification problem. In this paper we present an approach that uses models at runtime to facilitate the specification of non-functional requirements and resources, aiming to facilitate dynamic support for application execution in cloud computing environments with shared resources.
{"title":"On modeling and satisfaction of non-functional requirements using cloud computing","authors":"R. Gomes, F. Costa, N. Bencomo","doi":"10.1109/LatinCloud.2013.6842213","DOIUrl":"https://doi.org/10.1109/LatinCloud.2013.6842213","url":null,"abstract":"Specification of the non-functional requirements of applications and determining the required resources for their execution are activities that demand a great deal of technical knowledge, frequently resulting in an inefficient use of resources. Cloud computing is an alternative for provisioning of resources, which can be done using either the provider's own infrastructure or the infrastructure of one or more public clouds, or even a combination of both. It enables more flexibly/elastic use of resources, but does not solve the specification problem. In this paper we present an approach that uses models at runtime to facilitate the specification of non-functional requirements and resources, aiming to facilitate dynamic support for application execution in cloud computing environments with shared resources.","PeriodicalId":344490,"journal":{"name":"2nd IEEE Latin American Conference on Cloud Computing and Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129713994","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 : 2013-12-01DOI: 10.1109/LatinCloud.2013.6842221
Walisson F. Pereira, L. Bittencourt, N. Fonseca
Data-intensive workflows can require the use of intermediary data storage in the order of terabytes. Thus, planning the execution of such workflows in the cloud considering only processing demand, regardless its data storage needs, leads to performance decrease and potential increase in costs. In this paper, we present an integer linear program scheduler that considers disk storage scheduling besides the task scheduling based on processor time. The proposed scheduler aims to achieve the lowest economic cost while serving a deadline set by the user. The results show that the scheduler can find good schedules in situations where the disk size of rented virtual machines is a limiting factor.
{"title":"Scheduler for data-intensive workflows in public clouds","authors":"Walisson F. Pereira, L. Bittencourt, N. Fonseca","doi":"10.1109/LatinCloud.2013.6842221","DOIUrl":"https://doi.org/10.1109/LatinCloud.2013.6842221","url":null,"abstract":"Data-intensive workflows can require the use of intermediary data storage in the order of terabytes. Thus, planning the execution of such workflows in the cloud considering only processing demand, regardless its data storage needs, leads to performance decrease and potential increase in costs. In this paper, we present an integer linear program scheduler that considers disk storage scheduling besides the task scheduling based on processor time. The proposed scheduler aims to achieve the lowest economic cost while serving a deadline set by the user. The results show that the scheduler can find good schedules in situations where the disk size of rented virtual machines is a limiting factor.","PeriodicalId":344490,"journal":{"name":"2nd IEEE Latin American Conference on Cloud Computing and Communications","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133447204","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 : 2013-12-01DOI: 10.1109/LatinCloud.2013.6842216
Jonathan Pinto Barbosa, V. Oliveira, A. Mury, B. Schulze
Scientific computing often requires high performance computational resources to perform large scale simulations in order to achieve appropriate results. These demand have been addressed with dedicated High-Performance Parallel and Distributed Computing (HPDC) infrastructures, but nowadays, a new dimension has been added by Cloud model, which has gathered significant attention from scientific communities, as a potential approach to address a broad range of computing demands. The challenge now is how to provide the correct balance between real and virtualized infrastructure, able to comply scientific application requirements. Our Neblina approach presents a model combining real and virtual environments, with scientific applications being scheduled on the resources based on the application categorization, the virtualization layer capabilities and the hardware infrastructure characteristics, aiming to optimize the use of the computational resources, minimizing the loss of performance, due the virtualization layer.
{"title":"Neblina - Scientific management environments for clouds","authors":"Jonathan Pinto Barbosa, V. Oliveira, A. Mury, B. Schulze","doi":"10.1109/LatinCloud.2013.6842216","DOIUrl":"https://doi.org/10.1109/LatinCloud.2013.6842216","url":null,"abstract":"Scientific computing often requires high performance computational resources to perform large scale simulations in order to achieve appropriate results. These demand have been addressed with dedicated High-Performance Parallel and Distributed Computing (HPDC) infrastructures, but nowadays, a new dimension has been added by Cloud model, which has gathered significant attention from scientific communities, as a potential approach to address a broad range of computing demands. The challenge now is how to provide the correct balance between real and virtualized infrastructure, able to comply scientific application requirements. Our Neblina approach presents a model combining real and virtual environments, with scientific applications being scheduled on the resources based on the application categorization, the virtualization layer capabilities and the hardware infrastructure characteristics, aiming to optimize the use of the computational resources, minimizing the loss of performance, due the virtualization layer.","PeriodicalId":344490,"journal":{"name":"2nd IEEE Latin American Conference on Cloud Computing and Communications","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117156709","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 : 2013-12-01DOI: 10.1109/LatinCloud.2013.6842218
Karim Benzidane, Saad Khoudali, A. Sekkaki
Cloud Computing (CC) is a large-scale distributed computing paradigm that is driven by economies of scale, in which a pool of abstracted, virtualized, dynamically-scalable, managed computing power, storage, platforms, and services are delivered on demand to external customers over the Internet. On the other hand, one of the key enablers for building Cloud environments is Virtualization. It offers a great level of efficiency and scalability that makes the complex processing of the Cloud possible. However, with these advantages come certain limitations, especially in relation to security. Virtualization vulnerabilities and more specifically isolation, creates new targets for intrusion due to the complexity of access and difficulty in monitoring all interconnection points between systems, applications, and data sets. Hence, without strict controls put in place within the Cloud, guests could violate and bypass security policies, intercept unauthorized client data, and initiate or become the target of security attacks. This article discusses the security and the visibility issues of inter-VM traffic, by proposing a solution for it within the Cloud context. The proposed approach provides Virtual Machines (VMs) authentication, communication integrity, and enforces trusted transactions, through security mechanisms, structures, policies, and various intrusion detection techniques.
{"title":"Secured architecture for inter-VM traffic in a Cloud environment","authors":"Karim Benzidane, Saad Khoudali, A. Sekkaki","doi":"10.1109/LatinCloud.2013.6842218","DOIUrl":"https://doi.org/10.1109/LatinCloud.2013.6842218","url":null,"abstract":"Cloud Computing (CC) is a large-scale distributed computing paradigm that is driven by economies of scale, in which a pool of abstracted, virtualized, dynamically-scalable, managed computing power, storage, platforms, and services are delivered on demand to external customers over the Internet. On the other hand, one of the key enablers for building Cloud environments is Virtualization. It offers a great level of efficiency and scalability that makes the complex processing of the Cloud possible. However, with these advantages come certain limitations, especially in relation to security. Virtualization vulnerabilities and more specifically isolation, creates new targets for intrusion due to the complexity of access and difficulty in monitoring all interconnection points between systems, applications, and data sets. Hence, without strict controls put in place within the Cloud, guests could violate and bypass security policies, intercept unauthorized client data, and initiate or become the target of security attacks. This article discusses the security and the visibility issues of inter-VM traffic, by proposing a solution for it within the Cloud context. The proposed approach provides Virtual Machines (VMs) authentication, communication integrity, and enforces trusted transactions, through security mechanisms, structures, policies, and various intrusion detection techniques.","PeriodicalId":344490,"journal":{"name":"2nd IEEE Latin American Conference on Cloud Computing and Communications","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129965130","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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