The Internet of Things (IoT) already became an enabling technology in many areas. In Smart Waste Management (SWM) systems, IoT helps to interconnect such loosely coupled components as garbage containers, sensors, trucks, cloud services, recycling factories and devices of citizens. We discuss our approach for managing physical infrastructure and software components which form an SWM system and enable its interaction with other Smart City services and applications. We described an architecture of interconnection between sensors and cloud through the LoRaWAN protocol and usage of that information by external system.
{"title":"Enabling smart waste management with sensorized garbage bins and low power data communications network","authors":"P. Fedchenkov, A. Zaslavsky, I. Sosunova","doi":"10.1145/3131542.3140264","DOIUrl":"https://doi.org/10.1145/3131542.3140264","url":null,"abstract":"The Internet of Things (IoT) already became an enabling technology in many areas. In Smart Waste Management (SWM) systems, IoT helps to interconnect such loosely coupled components as garbage containers, sensors, trucks, cloud services, recycling factories and devices of citizens. We discuss our approach for managing physical infrastructure and software components which form an SWM system and enable its interaction with other Smart City services and applications. We described an architecture of interconnection between sensors and cloud through the LoRaWAN protocol and usage of that information by external system.","PeriodicalId":166408,"journal":{"name":"Proceedings of the Seventh International Conference on the Internet of Things","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114502281","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}
M. Robles, Edgar José Ramos, N. Beijar, N. Narendra
The concept of Internet of Things (IoT) envisions that any type of device should be able to be connected in any type of environment. Due to the heterogeneity of the scenarios where IoT is applied, the capability discovery and dynamic relationship establishment between devices become relevant. One way to define relation between devices is through similarities in functionality. Thus, we define that two devices are close semantically, or have a short semantic distance between them, when the devices have similar functionalities. We have proposed in a previous work a metric called LwRSD (LWM2M Resource Semantic Distance) to calculate similarities between devices utilizing a subjective approach for weighting properties. In this paper, we describe an ontology called SENACT that allows developing a method to calculate the Semantic Distance between devices using weights determined in an objective way. SENACT builds axioms from sensing and actuation concepts. The results shows that is it possible to group devices with similar functionalities in an objective way using SENACT and uncover properties shared between devices that are not immediately apparent.
{"title":"Calculating LWM2M resource semantic distance through SENACT ontology","authors":"M. Robles, Edgar José Ramos, N. Beijar, N. Narendra","doi":"10.1145/3131542.3131555","DOIUrl":"https://doi.org/10.1145/3131542.3131555","url":null,"abstract":"The concept of Internet of Things (IoT) envisions that any type of device should be able to be connected in any type of environment. Due to the heterogeneity of the scenarios where IoT is applied, the capability discovery and dynamic relationship establishment between devices become relevant. One way to define relation between devices is through similarities in functionality. Thus, we define that two devices are close semantically, or have a short semantic distance between them, when the devices have similar functionalities. We have proposed in a previous work a metric called LwRSD (LWM2M Resource Semantic Distance) to calculate similarities between devices utilizing a subjective approach for weighting properties. In this paper, we describe an ontology called SENACT that allows developing a method to calculate the Semantic Distance between devices using weights determined in an objective way. SENACT builds axioms from sensing and actuation concepts. The results shows that is it possible to group devices with similar functionalities in an objective way using SENACT and uncover properties shared between devices that are not immediately apparent.","PeriodicalId":166408,"journal":{"name":"Proceedings of the Seventh International Conference on the Internet of Things","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131389047","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}
Hyunjae Lee, Eunji Jeong, Donghyun Kang, Jinmyeong Kim, S. Ha
As Internet of Things (IoT) has received substantial attention in industry and academia recently, many IoT devices and IoT platforms have been proposed and being developed. In this paper we propose a novel IoT platform, called SoPIoT, that is different from existent IoT platforms in several aspects. Since a device is abstracted with a set of services it provides, any computing resources can be easily integrated into the platform. SoPIoT allows a user to define a composite service dynamically at run-time by a script language program. To SoPIoT, the IoT system looks like a distributed system that consists of many computing resources, running multiple applications currently where an application corresponds to a composite service. The central middleware maps and schedules the services to the computing resources. The scalability of SoPIoT is achieved by forming the hierarchy of middlewares. The viability of the proposed IoT platform is confirmed by building a smart office test-bed. Experimental results show that a central middleware can support more than 1,000 devices.
{"title":"A novel service-oriented platform for the internet of things","authors":"Hyunjae Lee, Eunji Jeong, Donghyun Kang, Jinmyeong Kim, S. Ha","doi":"10.1145/3131542.3131549","DOIUrl":"https://doi.org/10.1145/3131542.3131549","url":null,"abstract":"As Internet of Things (IoT) has received substantial attention in industry and academia recently, many IoT devices and IoT platforms have been proposed and being developed. In this paper we propose a novel IoT platform, called SoPIoT, that is different from existent IoT platforms in several aspects. Since a device is abstracted with a set of services it provides, any computing resources can be easily integrated into the platform. SoPIoT allows a user to define a composite service dynamically at run-time by a script language program. To SoPIoT, the IoT system looks like a distributed system that consists of many computing resources, running multiple applications currently where an application corresponds to a composite service. The central middleware maps and schedules the services to the computing resources. The scalability of SoPIoT is achieved by forming the hierarchy of middlewares. The viability of the proposed IoT platform is confirmed by building a smart office test-bed. Experimental results show that a central middleware can support more than 1,000 devices.","PeriodicalId":166408,"journal":{"name":"Proceedings of the Seventh International Conference on the Internet of Things","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123813358","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}
M. Tomlein, Sudershan Boovaraghavan, Yuvraj Agarwal, A. Dey
Despite the breadth of related work, enabling end-users of varying technical ability to leverage sensor data to control their Internet of Things (IoT)-enabled installations remains a challenge. This work proposes a unified interface that provides three building blocks to support the end-user configuration of IoT environments: capturing higher-level events in the installation through virtual sensors, construction of automation rules with a visual overview of the current configuration and support for sharing configuration between end-users using a recommendation mechanism.
{"title":"CharIoT: an end-user programming environment for the IoT","authors":"M. Tomlein, Sudershan Boovaraghavan, Yuvraj Agarwal, A. Dey","doi":"10.1145/3131542.3140261","DOIUrl":"https://doi.org/10.1145/3131542.3140261","url":null,"abstract":"Despite the breadth of related work, enabling end-users of varying technical ability to leverage sensor data to control their Internet of Things (IoT)-enabled installations remains a challenge. This work proposes a unified interface that provides three building blocks to support the end-user configuration of IoT environments: capturing higher-level events in the installation through virtual sensors, construction of automation rules with a visual overview of the current configuration and support for sharing configuration between end-users using a recommendation mechanism.","PeriodicalId":166408,"journal":{"name":"Proceedings of the Seventh International Conference on the Internet of Things","volume":"97 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120823010","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}
P. Missier, Shaimaa Bajoudah, A. Capossele, A. Gaglione, M. Nati
Internet of Things (IoT) data are increasingly viewed as a new form of massively distributed and large scale digital assets, which are continuously generated by millions of connected devices. The real value of such assets can only be realized by allowing IoT data trading to occur on a marketplace that rewards every single producer and consumer, at a very granular level. Crucially, we believe that such a marketplace should not be owned by anybody, and should instead fairly and transparently self-enforce a well defined set of governance rules. In this paper we address some of the technical challenges involved in realizing such a marketplace. We leverage emerging blockchain technologies to build a decentralized, trusted, transparent and open architecture for IoT traffic metering and contract compliance, on top of the largely adopted IoT brokered data infrastructure. We discuss an Ethereum-based prototype implementation and experimentally evaluate the overhead cost associated with Smart Contract transactions, concluding that a viable business model can indeed be associated with our technical approach.
{"title":"Mind my value: a decentralized infrastructure for fair and trusted IoT data trading","authors":"P. Missier, Shaimaa Bajoudah, A. Capossele, A. Gaglione, M. Nati","doi":"10.1145/3131542.3131564","DOIUrl":"https://doi.org/10.1145/3131542.3131564","url":null,"abstract":"Internet of Things (IoT) data are increasingly viewed as a new form of massively distributed and large scale digital assets, which are continuously generated by millions of connected devices. The real value of such assets can only be realized by allowing IoT data trading to occur on a marketplace that rewards every single producer and consumer, at a very granular level. Crucially, we believe that such a marketplace should not be owned by anybody, and should instead fairly and transparently self-enforce a well defined set of governance rules. In this paper we address some of the technical challenges involved in realizing such a marketplace. We leverage emerging blockchain technologies to build a decentralized, trusted, transparent and open architecture for IoT traffic metering and contract compliance, on top of the largely adopted IoT brokered data infrastructure. We discuss an Ethereum-based prototype implementation and experimentally evaluate the overhead cost associated with Smart Contract transactions, concluding that a viable business model can indeed be associated with our technical approach.","PeriodicalId":166408,"journal":{"name":"Proceedings of the Seventh International Conference on the Internet of Things","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127220394","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}
Blockchain, the underlying technology of cryptocurrency networks like Bitcoin, can prove to be essential towards realizing the vision of a decentralized, secure, and open Internet of Things (IoT) revolution. There is a growing interest in many research groups towards leveraging blockchains to provide IoT data privacy without the need for a centralized data access model. This paper aims to propose a decentralized access model for IoT data, using a network architecture that we call a modular consortium architecture for IoT and blockchains. The proposed architecture facilitates IoT communications on top of a software stack of blockchains and peer-to-peer data storage mechanisms. The architecture is aimed to have privacy built into it, and to be adaptable for various IoT use cases. To understand the feasibility and deployment considerations for implementing the proposed architecture, we conduct performance analysis of existing blockchain development platforms, Ethereum and Monax.
{"title":"IoT data privacy via blockchains and IPFS","authors":"M. Ali, Koustabh Dolui, Fabio Antonelli","doi":"10.1145/3131542.3131563","DOIUrl":"https://doi.org/10.1145/3131542.3131563","url":null,"abstract":"Blockchain, the underlying technology of cryptocurrency networks like Bitcoin, can prove to be essential towards realizing the vision of a decentralized, secure, and open Internet of Things (IoT) revolution. There is a growing interest in many research groups towards leveraging blockchains to provide IoT data privacy without the need for a centralized data access model. This paper aims to propose a decentralized access model for IoT data, using a network architecture that we call a modular consortium architecture for IoT and blockchains. The proposed architecture facilitates IoT communications on top of a software stack of blockchains and peer-to-peer data storage mechanisms. The architecture is aimed to have privacy built into it, and to be adaptable for various IoT use cases. To understand the feasibility and deployment considerations for implementing the proposed architecture, we conduct performance analysis of existing blockchain development platforms, Ethereum and Monax.","PeriodicalId":166408,"journal":{"name":"Proceedings of the Seventh International Conference on the Internet of Things","volume":"168 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127550477","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}
M. Otani, Tomoaki Matsuda, Nitish Rajoria, J. Mitsugi, H. Ichikawa, Yuusuke Kawakita
Interest in structural health monitoring for which sensors are used to detect structural damage has increased. For low-cost installation, these sensors are required to be batteryless and wireless. The objective of this study is to realize structural health monitoring for large-scale structures using a multiple subcarrier multiple access scheme that functionally enhances sub-carrier methods in radio-frequency identification (RFID) communication. When the target structure is of large scale, it is necessary to divide the structure into several zones because of communication distance restrictions. In this case, some wireless sensor nodes are located in zones where adjacent transceiver ranges overlap, thereby transmitting their sensing signals to both zones; thus, the problem of inter-zone interference due to unintended subcarriers arises. Therefore, we propose a method of inter-zone interference avoidance in which channels are reserved for wireless sensors overlapping adjacent zones. Evaluation via simulation reveals that the average communication capacity reduction can be suppressed compared with the case without channel reservation.
{"title":"Inter-zone interference avoidance using channel reservation in multiple subcarrier multiple access scheme","authors":"M. Otani, Tomoaki Matsuda, Nitish Rajoria, J. Mitsugi, H. Ichikawa, Yuusuke Kawakita","doi":"10.1145/3131542.3131546","DOIUrl":"https://doi.org/10.1145/3131542.3131546","url":null,"abstract":"Interest in structural health monitoring for which sensors are used to detect structural damage has increased. For low-cost installation, these sensors are required to be batteryless and wireless. The objective of this study is to realize structural health monitoring for large-scale structures using a multiple subcarrier multiple access scheme that functionally enhances sub-carrier methods in radio-frequency identification (RFID) communication. When the target structure is of large scale, it is necessary to divide the structure into several zones because of communication distance restrictions. In this case, some wireless sensor nodes are located in zones where adjacent transceiver ranges overlap, thereby transmitting their sensing signals to both zones; thus, the problem of inter-zone interference due to unintended subcarriers arises. Therefore, we propose a method of inter-zone interference avoidance in which channels are reserved for wireless sensors overlapping adjacent zones. Evaluation via simulation reveals that the average communication capacity reduction can be suppressed compared with the case without channel reservation.","PeriodicalId":166408,"journal":{"name":"Proceedings of the Seventh International Conference on the Internet of Things","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132789487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work demonstrates a complete setup of a distributed LoRaWAN-based data-acquisition system where individual LoRa end-devices can be supervised by a remote debugging environment. We present the whole chain of data processing from an embedded Indoor Air Quality (IAQ) monitoring sensor in the field up to the data-storage and visualization for human end-users connected over the cloud. In particular, we focus on the development-process of the low-power sensor node itself, which plays a key role in every IoT scenario. The sensor node's hardware is realized with a low-cost resource-constrained microcontroller unit (MCU) which executes the sensor-application as well as the embedded LoRaWAN stack. We demonstrate the possibility of remote incircuit-debugging of the embedded wireless node's firmware during operation in the field. Together with the possibility to analyze the power consumption and the radio-frequency spectrum of the wireless node as well as undesired RF interferer the ability to remotely update and debug the MCU's firmware allows to optimize the sensor node for the specific usage scenario and the place of its final operation.
{"title":"Advanced remote debugging of LoRa-enabled IoT sensor nodes","authors":"Albert Pötsch, Florian Haslhofer, A. Springer","doi":"10.1145/3131542.3140259","DOIUrl":"https://doi.org/10.1145/3131542.3140259","url":null,"abstract":"This work demonstrates a complete setup of a distributed LoRaWAN-based data-acquisition system where individual LoRa end-devices can be supervised by a remote debugging environment. We present the whole chain of data processing from an embedded Indoor Air Quality (IAQ) monitoring sensor in the field up to the data-storage and visualization for human end-users connected over the cloud. In particular, we focus on the development-process of the low-power sensor node itself, which plays a key role in every IoT scenario. The sensor node's hardware is realized with a low-cost resource-constrained microcontroller unit (MCU) which executes the sensor-application as well as the embedded LoRaWAN stack. We demonstrate the possibility of remote incircuit-debugging of the embedded wireless node's firmware during operation in the field. Together with the possibility to analyze the power consumption and the radio-frequency spectrum of the wireless node as well as undesired RF interferer the ability to remotely update and debug the MCU's firmware allows to optimize the sensor node for the specific usage scenario and the place of its final operation.","PeriodicalId":166408,"journal":{"name":"Proceedings of the Seventh International Conference on the Internet of Things","volume":"24 7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133797936","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}
Markel Iglesias-Urkia, A. Urbieta, Jorge Parra, D. Casado-Mansilla
Smart Grids are one of the main consequences of the digitalization of electrical grid infrastructures that aim to improve energy saving and efficiency. Within Smart Grids, different devices and electrical substations communicate with each other and need to be accessible from the outside. Thus, the need of embracing standards, such as those of International Electrotechnical Commission's (IEC), is pivotal. IEC 61850 is a standard that covers such a need, and different communication protocols have been proposed to fulfill the features that the standard proposes. Most proposals focus on heavyweight protocols. However, the growth of the Internet of Things (IoT) demands resource-constrained devices to also participate in IoT networks. In this regard, new protocols have been designed and developed, such as the Constrained Application Protocol (CoAP). The work presented in this paper adopts CoAP to provide a full mapping of the functionalities specified in IEC 61850 for electrical substations. Furthermore, an analytical and critical review of the already proposed mapping approaches is provided. Future lines of research towards accelerating the adoption of IoT and Web of Things standards in Smart Grid scenarios are also provided.
{"title":"IEC 61850 meets CoAP: towards the integration of smart grids and IoT standards","authors":"Markel Iglesias-Urkia, A. Urbieta, Jorge Parra, D. Casado-Mansilla","doi":"10.1145/3131542.3131545","DOIUrl":"https://doi.org/10.1145/3131542.3131545","url":null,"abstract":"Smart Grids are one of the main consequences of the digitalization of electrical grid infrastructures that aim to improve energy saving and efficiency. Within Smart Grids, different devices and electrical substations communicate with each other and need to be accessible from the outside. Thus, the need of embracing standards, such as those of International Electrotechnical Commission's (IEC), is pivotal. IEC 61850 is a standard that covers such a need, and different communication protocols have been proposed to fulfill the features that the standard proposes. Most proposals focus on heavyweight protocols. However, the growth of the Internet of Things (IoT) demands resource-constrained devices to also participate in IoT networks. In this regard, new protocols have been designed and developed, such as the Constrained Application Protocol (CoAP). The work presented in this paper adopts CoAP to provide a full mapping of the functionalities specified in IEC 61850 for electrical substations. Furthermore, an analytical and critical review of the already proposed mapping approaches is provided. Future lines of research towards accelerating the adoption of IoT and Web of Things standards in Smart Grid scenarios are also provided.","PeriodicalId":166408,"journal":{"name":"Proceedings of the Seventh International Conference on the Internet of Things","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130657723","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}
Over the past years, the IoT conference has become a gathering place for leading experts from industry and academia in the field of the Internet of Things. In addition to the core technical program with 21 accepted paper contributions from 15 countries, IoT 2017, which was held from October 22--25 in Linz, Austria, comprised two keynotes, five workshops, a doctoral colloquium, posters, demonstrations, art projects, and a panel session on the topic of cognitive products in the context of the Industrie 4.0 paradigm.
{"title":"IoT 2017: the Seventh International Conference on the Internet of Things","authors":"S. Mayer, Stefan Schneegass","doi":"10.1145/3131542.3131543","DOIUrl":"https://doi.org/10.1145/3131542.3131543","url":null,"abstract":"Over the past years, the IoT conference has become a gathering place for leading experts from industry and academia in the field of the Internet of Things. In addition to the core technical program with 21 accepted paper contributions from 15 countries, IoT 2017, which was held from October 22--25 in Linz, Austria, comprised two keynotes, five workshops, a doctoral colloquium, posters, demonstrations, art projects, and a panel session on the topic of cognitive products in the context of the Industrie 4.0 paradigm.","PeriodicalId":166408,"journal":{"name":"Proceedings of the Seventh International Conference on the Internet of Things","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124225401","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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