Pub Date : 2013-12-02DOI: 10.1109/CloudCom.2013.103
Juan Angel Lorenzo del Castillo, Kate Mallichan, Yahya Al-Hazmi
There is an increasing number of cloud platforms emerging in both academia and industry. They often federate resources from multiple infrastructures in order to benefit from the unique features that each presents. After introducing the main capabilities and features of OpenStack, this article addresses the integration of OpenStack-based platforms into larger, heterogeneous multi-cloud infrastructures, taking the EU FP7 BonFIRE project as an integration use case. Ultimately, we aim to contribute to the state of the art and provide guidelines to integrators looking to federate Open Stack testbeds into more complex architectures.
{"title":"OpenStack Federation in Experimentation Multi-cloud Testbeds","authors":"Juan Angel Lorenzo del Castillo, Kate Mallichan, Yahya Al-Hazmi","doi":"10.1109/CloudCom.2013.103","DOIUrl":"https://doi.org/10.1109/CloudCom.2013.103","url":null,"abstract":"There is an increasing number of cloud platforms emerging in both academia and industry. They often federate resources from multiple infrastructures in order to benefit from the unique features that each presents. After introducing the main capabilities and features of OpenStack, this article addresses the integration of OpenStack-based platforms into larger, heterogeneous multi-cloud infrastructures, taking the EU FP7 BonFIRE project as an integration use case. Ultimately, we aim to contribute to the state of the art and provide guidelines to integrators looking to federate Open Stack testbeds into more complex architectures.","PeriodicalId":198053,"journal":{"name":"2013 IEEE 5th International Conference on Cloud Computing Technology and Science","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122924240","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 : 2013-12-02DOI: 10.1109/CloudCom.2013.77
M. Mohanty, Wei Tsang Ooi, P. Atrey
Advances in cloud computing have allowed volume rendering tasks, typically done by volume ray-casting, to be outsourced to cloud data centers. The availability of volume data and rendered images (which can contain important information such as the disease information of a patient) to a third-party cloud provider, however, presents security and privacy challenges. This paper addresses these challenges by proposing a secure cloud-based volume ray-casting framework that distributes the rendering tasks among the data centers and hides the information that is exchanged between the server and a data center, between two data centers, and between a data center and the client by using Shamir's secret sharing, such that none of the data centers has enough information to know the secret data and/or rendered image. Experiments and analyses show that our framework is highly secure and requires low computation cost.
{"title":"Secure Cloud-Based Volume Ray-Casting","authors":"M. Mohanty, Wei Tsang Ooi, P. Atrey","doi":"10.1109/CloudCom.2013.77","DOIUrl":"https://doi.org/10.1109/CloudCom.2013.77","url":null,"abstract":"Advances in cloud computing have allowed volume rendering tasks, typically done by volume ray-casting, to be outsourced to cloud data centers. The availability of volume data and rendered images (which can contain important information such as the disease information of a patient) to a third-party cloud provider, however, presents security and privacy challenges. This paper addresses these challenges by proposing a secure cloud-based volume ray-casting framework that distributes the rendering tasks among the data centers and hides the information that is exchanged between the server and a data center, between two data centers, and between a data center and the client by using Shamir's secret sharing, such that none of the data centers has enough information to know the secret data and/or rendered image. Experiments and analyses show that our framework is highly secure and requires low computation cost.","PeriodicalId":198053,"journal":{"name":"2013 IEEE 5th International Conference on Cloud Computing Technology and Science","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115582118","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 : 2013-12-02DOI: 10.1109/CloudCom.2013.65
José Simão, N. Rameshan, L. Veiga
Cloud platforms are becoming more prevalent in every computational domain, particularly in e-Science. A typical scientific workload will have a long execution time or be data intensive. Providing an execution environment for these applications, which belong to different tenants, has to deal with the horizontal scaling of execution flows (i.e. threads) and an effective allocation of resources that takes into account the effective progress made by each tenant. While this is trivial for Bag-of-Tasks and embarrassingly parallel jobs, it is hard for HPC single-process multi-threaded applications because they cannot be scaled up automatically just by adding more virtual machines to execute the workload. In this paper we present MengTian, a distributed execution environment or platform capable of addressing the issues above. It encompasses several extensions to the Java execution environment, ranging from middleware to the virtual machine code and libraries. Our Java-based platform provides a Single System Image abstraction supported by a Partially Global Address Space to transparently spawn threads across a cluster of machines. It monitors progress with different levels-of-detail and accounts and restricts resource consumption. The overall goal is to redistribute resources among different JVM instances, increasing the unitary outcome of the progress vs. resource usage ratio over time.
{"title":"Resource-Aware Scaling of Multi-threaded Java Applications in Multi-tenancy Scenarios","authors":"José Simão, N. Rameshan, L. Veiga","doi":"10.1109/CloudCom.2013.65","DOIUrl":"https://doi.org/10.1109/CloudCom.2013.65","url":null,"abstract":"Cloud platforms are becoming more prevalent in every computational domain, particularly in e-Science. A typical scientific workload will have a long execution time or be data intensive. Providing an execution environment for these applications, which belong to different tenants, has to deal with the horizontal scaling of execution flows (i.e. threads) and an effective allocation of resources that takes into account the effective progress made by each tenant. While this is trivial for Bag-of-Tasks and embarrassingly parallel jobs, it is hard for HPC single-process multi-threaded applications because they cannot be scaled up automatically just by adding more virtual machines to execute the workload. In this paper we present MengTian, a distributed execution environment or platform capable of addressing the issues above. It encompasses several extensions to the Java execution environment, ranging from middleware to the virtual machine code and libraries. Our Java-based platform provides a Single System Image abstraction supported by a Partially Global Address Space to transparently spawn threads across a cluster of machines. It monitors progress with different levels-of-detail and accounts and restricts resource consumption. The overall goal is to redistribute resources among different JVM instances, increasing the unitary outcome of the progress vs. resource usage ratio over time.","PeriodicalId":198053,"journal":{"name":"2013 IEEE 5th International Conference on Cloud Computing Technology and Science","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116259108","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 : 2013-12-02DOI: 10.1109/CloudCom.2013.75
Ronan-Alexandre Cherrueau, Mario Südholt, O. Chebaro
Existing approaches to the adaptation of workflows over Web services fall short in two respects. First, they only provide, if ever, limited means for taking into account the execution history of a workflow. Second, they do not support adaptations that require modifications not only at the service composition level but also at the levels of interceptors and service implementations. This is particular problematic for the enforcement of security properties over workflows: enforcing authorization properties, for instance, frequently requires execution contexts to be defined and modifications to be applied at all these abstraction levels of Web services. We present two main contributions in this context. First, we introduce workflow adaptation schemas (WAS), a new notion of generic protocol-based workflow adapters. WAS enable the declarative definition of adaptations involving complex service compositions and implementations. Second, we present two real-world security issues related to the use of OAuth 2.0, a recent and widely used framework for the authorization of resource accesses. As we motivate, these security issues require history-based adaptations over different abstraction levels of services. We then show how to resolve these issues using WAS.
{"title":"Adapting Workflows Using Generic Schemas: Application to the Security of Business Processes","authors":"Ronan-Alexandre Cherrueau, Mario Südholt, O. Chebaro","doi":"10.1109/CloudCom.2013.75","DOIUrl":"https://doi.org/10.1109/CloudCom.2013.75","url":null,"abstract":"Existing approaches to the adaptation of workflows over Web services fall short in two respects. First, they only provide, if ever, limited means for taking into account the execution history of a workflow. Second, they do not support adaptations that require modifications not only at the service composition level but also at the levels of interceptors and service implementations. This is particular problematic for the enforcement of security properties over workflows: enforcing authorization properties, for instance, frequently requires execution contexts to be defined and modifications to be applied at all these abstraction levels of Web services. We present two main contributions in this context. First, we introduce workflow adaptation schemas (WAS), a new notion of generic protocol-based workflow adapters. WAS enable the declarative definition of adaptations involving complex service compositions and implementations. Second, we present two real-world security issues related to the use of OAuth 2.0, a recent and widely used framework for the authorization of resource accesses. As we motivate, these security issues require history-based adaptations over different abstraction levels of services. We then show how to resolve these issues using WAS.","PeriodicalId":198053,"journal":{"name":"2013 IEEE 5th International Conference on Cloud Computing Technology and Science","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123712630","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 : 2013-12-02DOI: 10.1109/CloudCom.2013.102
D. Bernstein, Y. Demchenko
This paper presents the current work of the IEEE Intercloud Testbed project. The notion of an Intercloud has been an active research topic. Within the IEEE several researchers formed a Standards Working Group (IEEE P2302) where a specific set of conventions, formats, and protocols were proposed. It was decided by those in the Standards Working Group that due to the scale, variability of component Compute Clouds, and lack of insight into extremely large Compute Cloud operational issues, such a system could not realistically be fully defined without live experimentation. Therefore it was decided to set up a specifically structured organization within the IEEE in parallel to the Standards Working Group, to provide a structure for a live, experimental testbed. This paper describes the innovative organizational structure and various policies were used to provide the desire context. Also covered are how we sorted the issues around governance of the namespace, and the technical details of reference "Root" and "Exchange" functions. Ongoing work includes the plan to bootstrap the new testbed.
{"title":"The IEEE Intercloud Testbed -- Creating the Global Cloud of Clouds","authors":"D. Bernstein, Y. Demchenko","doi":"10.1109/CloudCom.2013.102","DOIUrl":"https://doi.org/10.1109/CloudCom.2013.102","url":null,"abstract":"This paper presents the current work of the IEEE Intercloud Testbed project. The notion of an Intercloud has been an active research topic. Within the IEEE several researchers formed a Standards Working Group (IEEE P2302) where a specific set of conventions, formats, and protocols were proposed. It was decided by those in the Standards Working Group that due to the scale, variability of component Compute Clouds, and lack of insight into extremely large Compute Cloud operational issues, such a system could not realistically be fully defined without live experimentation. Therefore it was decided to set up a specifically structured organization within the IEEE in parallel to the Standards Working Group, to provide a structure for a live, experimental testbed. This paper describes the innovative organizational structure and various policies were used to provide the desire context. Also covered are how we sorted the issues around governance of the namespace, and the technical details of reference \"Root\" and \"Exchange\" functions. Ongoing work includes the plan to bootstrap the new testbed.","PeriodicalId":198053,"journal":{"name":"2013 IEEE 5th International Conference on Cloud Computing Technology and Science","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114944822","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 : 2013-12-02DOI: 10.1109/CloudCom.2013.144
B. Duncan, D. Pym, M. Whittington
Managing information security in the cloud is a challenge. Traditional checklist approaches to standards compliance may well provide compliance, but do not guarantee to provide security assurance. The complexity of cloud relationships must be acknowledged and explicitly managed by recognising the implications of self-interest of each party involved. We begin development of a conceptual modelling framework for cloud security assurance that can be used as a starting point for effective continuous security assurance, together with a high level of compliance.
{"title":"Developing a Conceptual Framework for Cloud Security Assurance","authors":"B. Duncan, D. Pym, M. Whittington","doi":"10.1109/CloudCom.2013.144","DOIUrl":"https://doi.org/10.1109/CloudCom.2013.144","url":null,"abstract":"Managing information security in the cloud is a challenge. Traditional checklist approaches to standards compliance may well provide compliance, but do not guarantee to provide security assurance. The complexity of cloud relationships must be acknowledged and explicitly managed by recognising the implications of self-interest of each party involved. We begin development of a conceptual modelling framework for cloud security assurance that can be used as a starting point for effective continuous security assurance, together with a high level of compliance.","PeriodicalId":198053,"journal":{"name":"2013 IEEE 5th International Conference on Cloud Computing Technology and Science","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126059709","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 : 2013-12-02DOI: 10.1109/CLOUDCOM.2013.161
T. Kirkham, B. Matthews, K. Jeffery, K. Djemame, Django Armstrong
Resource usage in Clouds can be improved by deploying applications with richer defined requirements. Such "richer requirements" involve wider application / user specific context capture expressed in interrelated models. The use of model based requirements is presented using input from test-beds monitoring resource use in terms of Trust, Risk, Eco-Efficiency and Cost (TREC) models. The results of this application illustrate the potential that richer requirements have for better management of resources in Clouds.
{"title":"Richer Requirements for Better Clouds","authors":"T. Kirkham, B. Matthews, K. Jeffery, K. Djemame, Django Armstrong","doi":"10.1109/CLOUDCOM.2013.161","DOIUrl":"https://doi.org/10.1109/CLOUDCOM.2013.161","url":null,"abstract":"Resource usage in Clouds can be improved by deploying applications with richer defined requirements. Such \"richer requirements\" involve wider application / user specific context capture expressed in interrelated models. The use of model based requirements is presented using input from test-beds monitoring resource use in terms of Trust, Risk, Eco-Efficiency and Cost (TREC) models. The results of this application illustrate the potential that richer requirements have for better management of resources in Clouds.","PeriodicalId":198053,"journal":{"name":"2013 IEEE 5th International Conference on Cloud Computing Technology and Science","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129312457","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 : 2013-12-02DOI: 10.1109/CloudCom.2013.124
Marouen Mechtri, D. Zeghlache, E. Zekri, I. Marshall
This paper presents a Cloud Networking Gateway (CNG) Manager, to enable networking of distributed cloud resources by authorized customers and to provide network control and configuration capabilities. The CNG Manager interconnects virtual machines, acquired from distributed heterogeneous resources and multiple providers, using generic gateways according to user connectivity requests. The CNG Manager is integrated with a "Cloud Broker" architecture for evaluation in the multiple providers context. The proposed framework extends and supports the current state of the art in cloud and software defined networks technologies with compatible connectivity control and management capabilities.
{"title":"Inter-cloud Networking Gateway Architecture","authors":"Marouen Mechtri, D. Zeghlache, E. Zekri, I. Marshall","doi":"10.1109/CloudCom.2013.124","DOIUrl":"https://doi.org/10.1109/CloudCom.2013.124","url":null,"abstract":"This paper presents a Cloud Networking Gateway (CNG) Manager, to enable networking of distributed cloud resources by authorized customers and to provide network control and configuration capabilities. The CNG Manager interconnects virtual machines, acquired from distributed heterogeneous resources and multiple providers, using generic gateways according to user connectivity requests. The CNG Manager is integrated with a \"Cloud Broker\" architecture for evaluation in the multiple providers context. The proposed framework extends and supports the current state of the art in cloud and software defined networks technologies with compatible connectivity control and management capabilities.","PeriodicalId":198053,"journal":{"name":"2013 IEEE 5th International Conference on Cloud Computing Technology and Science","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125076486","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 : 2013-12-02DOI: 10.1109/CloudCom.2013.43
José Simão, L. Veiga
Current clouds SLAs include compensation for customers (i.e. resource renters) with credits when average availability drops below a certain point. However, this credit scheme is too inflexible because consumers lose a non measurable quantity of performance and are only compensated later (i.e. in the next charging cycle). We propose to schedule cloud isolation and execution units, i.e. virtual machines (VMs), driven by the partial utility of applying a certain amount of resources (CPU, memory or bandwidth) to a given VM. This partial utility metric, specified by the customer, allows the provider to transfer resources between VMs. This is particularly relevant for private clouds where resources are not so abundant. We have defined a cost model that incorporates the partial utility the client gives to a certain level of depreciation when VMs are allocated in an over commit environment. CloudSim, a state of the art cloud simulator, was extended to support our partial utility-driven scheduling model. Using simulation scenarios with synthetic and real workloads, we show that our proposed scheduling strategy brings benefits to providers (i.e. revenue, resource utilization) and clients (i.e. workloads' execution time) by incorporating a SLA-based depreciation of computational power, allowing for more VMs to be allocated.
{"title":"Flexible SLAs in the Cloud with a Partial Utility-Driven Scheduling Architecture","authors":"José Simão, L. Veiga","doi":"10.1109/CloudCom.2013.43","DOIUrl":"https://doi.org/10.1109/CloudCom.2013.43","url":null,"abstract":"Current clouds SLAs include compensation for customers (i.e. resource renters) with credits when average availability drops below a certain point. However, this credit scheme is too inflexible because consumers lose a non measurable quantity of performance and are only compensated later (i.e. in the next charging cycle). We propose to schedule cloud isolation and execution units, i.e. virtual machines (VMs), driven by the partial utility of applying a certain amount of resources (CPU, memory or bandwidth) to a given VM. This partial utility metric, specified by the customer, allows the provider to transfer resources between VMs. This is particularly relevant for private clouds where resources are not so abundant. We have defined a cost model that incorporates the partial utility the client gives to a certain level of depreciation when VMs are allocated in an over commit environment. CloudSim, a state of the art cloud simulator, was extended to support our partial utility-driven scheduling model. Using simulation scenarios with synthetic and real workloads, we show that our proposed scheduling strategy brings benefits to providers (i.e. revenue, resource utilization) and clients (i.e. workloads' execution time) by incorporating a SLA-based depreciation of computational power, allowing for more VMs to be allocated.","PeriodicalId":198053,"journal":{"name":"2013 IEEE 5th International Conference on Cloud Computing Technology and Science","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122023199","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 : 2013-12-02DOI: 10.1109/CloudCom.2013.16
M. Chalkiadaki, K. Magoutis
In this paper we describe the architecture of a quality-of-service (QoS) infrastructure for achieving controlled application performance over the Cassandra distributed storage system. We present an implementation of our architecture and provide results from an evaluation using the Yahoo Cloud Serving Benchmark (YCSB) on the Amazon EC2 Cloud. A key focus of this paper is on a QoS-aware measurement-driven provisioning methodology. Our evaluation provides evidence that the methodology is effective in estimating application resource requirements and thus in achieving the type of controlled performance required by data intensive performance-critical applications. While our architecture is implemented and evaluated in the context of the Cassandra distributed storage system, its principles are general and can be applied to a variety of NoSQL systems.
{"title":"Managing Service Performance in the Cassandra Distributed Storage System","authors":"M. Chalkiadaki, K. Magoutis","doi":"10.1109/CloudCom.2013.16","DOIUrl":"https://doi.org/10.1109/CloudCom.2013.16","url":null,"abstract":"In this paper we describe the architecture of a quality-of-service (QoS) infrastructure for achieving controlled application performance over the Cassandra distributed storage system. We present an implementation of our architecture and provide results from an evaluation using the Yahoo Cloud Serving Benchmark (YCSB) on the Amazon EC2 Cloud. A key focus of this paper is on a QoS-aware measurement-driven provisioning methodology. Our evaluation provides evidence that the methodology is effective in estimating application resource requirements and thus in achieving the type of controlled performance required by data intensive performance-critical applications. While our architecture is implemented and evaluated in the context of the Cassandra distributed storage system, its principles are general and can be applied to a variety of NoSQL systems.","PeriodicalId":198053,"journal":{"name":"2013 IEEE 5th International Conference on Cloud Computing Technology and Science","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125696897","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：