Pub Date : 2020-11-02DOI: 10.1109/BCCA50787.2020.9274085
Koushik Bhargav Muthe, K. Sharma, Karthik Epperla Nagendra Sri
The market value of the Gaming industry was said to be over 138 Billion USD in 2019. Competitive Gaming or eSports was already included in the Asian Games 2020, and the Olympic committee is considering including eSports into Olympics 2024. The online gaming segment amounts up to 7 quintillion bytes of internet traffic every month. Most of this data is controlled by centralized gatekeepers like cloud agencies and game creators. This is causing many issues ranging from privacy concerns to latency. The game makers have complete rights over the game to arbitrarily change the rules, set prices for the assets, and control over game servers. Even the reward mechanisms in most of the games, including eSports, are controlled by the game producers, and these rewards have no real-world value. The motivation behind this research is to create a decentralized computation and token management infrastructure for game networks. This paper focuses on using Ethereum Blockchain, IPFS and ERC - Ethereum Request for Comment 1155 architecture to build a gaming-oriented public decentralized network.
{"title":"A Blockchain Based Decentralized Computing And NFT Infrastructure For Game Networks","authors":"Koushik Bhargav Muthe, K. Sharma, Karthik Epperla Nagendra Sri","doi":"10.1109/BCCA50787.2020.9274085","DOIUrl":"https://doi.org/10.1109/BCCA50787.2020.9274085","url":null,"abstract":"The market value of the Gaming industry was said to be over 138 Billion USD in 2019. Competitive Gaming or eSports was already included in the Asian Games 2020, and the Olympic committee is considering including eSports into Olympics 2024. The online gaming segment amounts up to 7 quintillion bytes of internet traffic every month. Most of this data is controlled by centralized gatekeepers like cloud agencies and game creators. This is causing many issues ranging from privacy concerns to latency. The game makers have complete rights over the game to arbitrarily change the rules, set prices for the assets, and control over game servers. Even the reward mechanisms in most of the games, including eSports, are controlled by the game producers, and these rewards have no real-world value. The motivation behind this research is to create a decentralized computation and token management infrastructure for game networks. This paper focuses on using Ethereum Blockchain, IPFS and ERC - Ethereum Request for Comment 1155 architecture to build a gaming-oriented public decentralized network.","PeriodicalId":218474,"journal":{"name":"2020 Second International Conference on Blockchain Computing and Applications (BCCA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116414014","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 : 2020-11-02DOI: 10.1109/BCCA50787.2020.9274456
Sina Rafati Niya, R. Beckmann, B. Stiller
The integration of the Internet-of-Things (IoT) and Blockchain (BC) for strong trust and decentralization shows potentials in use cases, such as supply chain tracing, smart cities, and health care. As a great number of IoT devices interacting in such cases, it is crucial to provide scalable and secure mechanisms for IoT data persistence within BCs. In this regard, sharding mechanisms have been employed to enhance the scalability of BCs. However, disconnections and delays of a BC’s distributed network can cause concerns for inter-shard and inter-miner synchronizations, eventually preventing the BC from reaching a high throughput. Thus, this work develops an IoT-oriented permissioned BC, which covers via a scalable Distributed Ledger (DL) a novel sharding mechanism for unstable distributed networks. Therefore, DLIT (Distributed Ledger for IoT Data) offers a novel two-layered transaction distribution, validation, and inter-shard synchronization, combined with authentication and verification mechanisms in support of a viable security level.
{"title":"DLIT: A Scalable Distributed Ledger for IoT Data","authors":"Sina Rafati Niya, R. Beckmann, B. Stiller","doi":"10.1109/BCCA50787.2020.9274456","DOIUrl":"https://doi.org/10.1109/BCCA50787.2020.9274456","url":null,"abstract":"The integration of the Internet-of-Things (IoT) and Blockchain (BC) for strong trust and decentralization shows potentials in use cases, such as supply chain tracing, smart cities, and health care. As a great number of IoT devices interacting in such cases, it is crucial to provide scalable and secure mechanisms for IoT data persistence within BCs. In this regard, sharding mechanisms have been employed to enhance the scalability of BCs. However, disconnections and delays of a BC’s distributed network can cause concerns for inter-shard and inter-miner synchronizations, eventually preventing the BC from reaching a high throughput. Thus, this work develops an IoT-oriented permissioned BC, which covers via a scalable Distributed Ledger (DL) a novel sharding mechanism for unstable distributed networks. Therefore, DLIT (Distributed Ledger for IoT Data) offers a novel two-layered transaction distribution, validation, and inter-shard synchronization, combined with authentication and verification mechanisms in support of a viable security level.","PeriodicalId":218474,"journal":{"name":"2020 Second International Conference on Blockchain Computing and Applications (BCCA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130373309","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 : 2020-11-02DOI: 10.1109/BCCA50787.2020.9274461
Sana Naz, S. Lee
The Blockchain with PoW consensus was first developed to solve the cryptocurrency double-spending and byzantine fault problem. The PoW consensus solved the problem very effectively. But due to its high computation and specialized hardware need, a lot of questions from society has been raised on the PoW consensus. To solve the limitations of PoW, a lot of other consensuses have been proposed in the literature as an alternative solution of PoW. However, the other consensus has its own benefits and drawbacks. So, to understand the consensus mechanisms our paper first describes the internal architecture of blockchain and then explain five consensuses of the blockchain network with its detailed comparative analysis of internal characteristic. We believe this comparative analysis will be helpful for those researchers who need to understand the major characteristics that a given consensus offer for their work.
{"title":"Why the new consensus mechanism is needed in blockchain technology?","authors":"Sana Naz, S. Lee","doi":"10.1109/BCCA50787.2020.9274461","DOIUrl":"https://doi.org/10.1109/BCCA50787.2020.9274461","url":null,"abstract":"The Blockchain with PoW consensus was first developed to solve the cryptocurrency double-spending and byzantine fault problem. The PoW consensus solved the problem very effectively. But due to its high computation and specialized hardware need, a lot of questions from society has been raised on the PoW consensus. To solve the limitations of PoW, a lot of other consensuses have been proposed in the literature as an alternative solution of PoW. However, the other consensus has its own benefits and drawbacks. So, to understand the consensus mechanisms our paper first describes the internal architecture of blockchain and then explain five consensuses of the blockchain network with its detailed comparative analysis of internal characteristic. We believe this comparative analysis will be helpful for those researchers who need to understand the major characteristics that a given consensus offer for their work.","PeriodicalId":218474,"journal":{"name":"2020 Second International Conference on Blockchain Computing and Applications (BCCA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131039539","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 : 2020-11-02DOI: 10.1109/BCCA50787.2020.9274083
Leonardo Pelonero, Andrea Fornaia, E. Tramontana
When having to improve waste collection and recycling, the citizen involvement is paramount. However, the lack of transparency about everyday activities and progresses towards long term goals could result in a loss of interest for the community and more difficulties in achieving desired results. In our proposed approach, data related to waste collection would be automatically passed from sensors to a blockchain smart contract. Such data include the amount of waste collected for each category from a citizen. By using a blockchain storing data related to collected waste, maximum data integrity and transparency would be ensured. Furthermore, citizens are provided with a smartphone app to read data from the blockchain, register other data concerning their activities, and check their fee balance. The overall solution, by ensuring that each citizen can monitor their progress and the global results achieved by the community, would address and foster participation.
{"title":"A Blockchain handling Data in a Waste Recycling Scenario and Fostering Participation","authors":"Leonardo Pelonero, Andrea Fornaia, E. Tramontana","doi":"10.1109/BCCA50787.2020.9274083","DOIUrl":"https://doi.org/10.1109/BCCA50787.2020.9274083","url":null,"abstract":"When having to improve waste collection and recycling, the citizen involvement is paramount. However, the lack of transparency about everyday activities and progresses towards long term goals could result in a loss of interest for the community and more difficulties in achieving desired results. In our proposed approach, data related to waste collection would be automatically passed from sensors to a blockchain smart contract. Such data include the amount of waste collected for each category from a citizen. By using a blockchain storing data related to collected waste, maximum data integrity and transparency would be ensured. Furthermore, citizens are provided with a smartphone app to read data from the blockchain, register other data concerning their activities, and check their fee balance. The overall solution, by ensuring that each citizen can monitor their progress and the global results achieved by the community, would address and foster participation.","PeriodicalId":218474,"journal":{"name":"2020 Second International Conference on Blockchain Computing and Applications (BCCA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129054648","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 : 2020-11-02DOI: 10.1109/BCCA50787.2020.9274450
Clemens Jeger, B. Rodrigues, E. Scheid, B. Stiller
One of the major concerns with cryptocurrencies is their price instability, driven by market speculation, underlying technology, and applications. Stablecoins were introduced to address volatility and to provide means for an electronic payment and a value store remaining stable, often being supported by physical assets or fiat currency (e.g., gold or US dollars, respectively). However, different collateralization mechanisms exist and different assets are pegged with the coin that can affect their stability in different ways. This work overviews stablecoin stability mechanisms, the current stablecoin market landscape, and the performance of major stablecoins during the 2020 financial market crisis due to the COVID-19 pandemic. Results from this analysis indicate that stablecoins’ performance during the financial crisis and, in particular, the market crash present a direct relation with their specific behavior attributed to different design aspects, including their popularity.
{"title":"Analysis of Stablecoins during the Global COVID-19 Pandemic","authors":"Clemens Jeger, B. Rodrigues, E. Scheid, B. Stiller","doi":"10.1109/BCCA50787.2020.9274450","DOIUrl":"https://doi.org/10.1109/BCCA50787.2020.9274450","url":null,"abstract":"One of the major concerns with cryptocurrencies is their price instability, driven by market speculation, underlying technology, and applications. Stablecoins were introduced to address volatility and to provide means for an electronic payment and a value store remaining stable, often being supported by physical assets or fiat currency (e.g., gold or US dollars, respectively). However, different collateralization mechanisms exist and different assets are pegged with the coin that can affect their stability in different ways. This work overviews stablecoin stability mechanisms, the current stablecoin market landscape, and the performance of major stablecoins during the 2020 financial market crisis due to the COVID-19 pandemic. Results from this analysis indicate that stablecoins’ performance during the financial crisis and, in particular, the market crash present a direct relation with their specific behavior attributed to different design aspects, including their popularity.","PeriodicalId":218474,"journal":{"name":"2020 Second International Conference on Blockchain Computing and Applications (BCCA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127538544","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 : 2020-11-02DOI: 10.1109/BCCA50787.2020.9274455
Benedikt Berger, Stefan Huber, Simon Pfeifhofer
Smart contracts encode critical application logic for realizing digital agreements in a tamper-proof form. Blockchains guarantee that smart contracts cannot be altered after the first deployment and that the execution is strictly followed. Smart contracts can only operate on data available on-chain. Oracles are bridging the gap between on-chain and off-chain data. Oracles introduce a wide range of security risks, which were already exploited in publicly known hacks. In this paper OraclesLink is proposed, which is a secure and developer-friendly architecture for using oracles within smart contracts. The goal of the architecture is to eliminate single points of failure and single sources of truth through distribution. In order to demonstrate feasibility, a proof-of-concept implementation is provided.
{"title":"OraclesLink: An architecture for secure oracle usage","authors":"Benedikt Berger, Stefan Huber, Simon Pfeifhofer","doi":"10.1109/BCCA50787.2020.9274455","DOIUrl":"https://doi.org/10.1109/BCCA50787.2020.9274455","url":null,"abstract":"Smart contracts encode critical application logic for realizing digital agreements in a tamper-proof form. Blockchains guarantee that smart contracts cannot be altered after the first deployment and that the execution is strictly followed. Smart contracts can only operate on data available on-chain. Oracles are bridging the gap between on-chain and off-chain data. Oracles introduce a wide range of security risks, which were already exploited in publicly known hacks. In this paper OraclesLink is proposed, which is a secure and developer-friendly architecture for using oracles within smart contracts. The goal of the architecture is to eliminate single points of failure and single sources of truth through distribution. In order to demonstrate feasibility, a proof-of-concept implementation is provided.","PeriodicalId":218474,"journal":{"name":"2020 Second International Conference on Blockchain Computing and Applications (BCCA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116982676","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 : 2020-11-02DOI: 10.1109/bcca50787.2020.9274079
{"title":"[Copyright notice]","authors":"","doi":"10.1109/bcca50787.2020.9274079","DOIUrl":"https://doi.org/10.1109/bcca50787.2020.9274079","url":null,"abstract":"","PeriodicalId":218474,"journal":{"name":"2020 Second International Conference on Blockchain Computing and Applications (BCCA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132327915","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 : 2020-11-02DOI: 10.1109/BCCA50787.2020.9274449
Majd Latah, Kübra Kalkan
Software-Defined Networking (SDN) is a promising networking architecture that enables central management along with network programmability. However, SDN brings additional security threats due to untrusted control and data planes. In this work, we focus on authenticating SDN’s data plane since it can be exploited to attack SDN’s control plane. As a result, the whole SDN network will be paralysed. On the other hand, Blockchain (BC) can be utilized to provide more secure data plane by introducing a fault-tolerant, decentralized and secure ledger without relying on any trusted third-party intermediaries. To this end, in this work we propose, DPSec, a consortium BC-based protocol for authenticating SDN’s data plane including SDN switches and hosts. We also provide a proof-of-concept that demonstrates the applicability and feasibility of our protocol in SDNs. Finally, we present a security analysis that shows how DPSec can address several attacks against SDNs including CVE-2018-1000155 vulnerability [1] that targets SDN controllers due to the untrusted data plane.
{"title":"DPSec: A blockchain-based data plane authentication protocol for SDNs","authors":"Majd Latah, Kübra Kalkan","doi":"10.1109/BCCA50787.2020.9274449","DOIUrl":"https://doi.org/10.1109/BCCA50787.2020.9274449","url":null,"abstract":"Software-Defined Networking (SDN) is a promising networking architecture that enables central management along with network programmability. However, SDN brings additional security threats due to untrusted control and data planes. In this work, we focus on authenticating SDN’s data plane since it can be exploited to attack SDN’s control plane. As a result, the whole SDN network will be paralysed. On the other hand, Blockchain (BC) can be utilized to provide more secure data plane by introducing a fault-tolerant, decentralized and secure ledger without relying on any trusted third-party intermediaries. To this end, in this work we propose, DPSec, a consortium BC-based protocol for authenticating SDN’s data plane including SDN switches and hosts. We also provide a proof-of-concept that demonstrates the applicability and feasibility of our protocol in SDNs. Finally, we present a security analysis that shows how DPSec can address several attacks against SDNs including CVE-2018-1000155 vulnerability [1] that targets SDN controllers due to the untrusted data plane.","PeriodicalId":218474,"journal":{"name":"2020 Second International Conference on Blockchain Computing and Applications (BCCA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131901203","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 : 2020-11-02DOI: 10.1109/BCCA50787.2020.9274451
Caner Korkmaz, Halil Eralp Kocas, Ahmet Uysal, Ahmed Masry, O. Ozkasap, Barış Akgün
Federated learning is a collaborative machine learning mechanism that allows multiple parties to develop a model without sharing the training data. It is a promising mechanism since it empowers collaboration in fields such as medicine and banking where data sharing is not favorable due to legal, technical, ethical, or safety issues without significantly sacrificing accuracy. In centralized federated learning, there is a single central server, and hence it has a single point of failure. Unlike centralized federated learning, decentralized federated learning does not depend on a single central server for the updates. In this paper, we propose a decentralized federated learning approach named Chain FL that makes use of the blockchain to delegate the responsibility of storing the model to the nodes on the network instead of a centralized server. Chain FL produced promising results on the MNIST digit recognition task with a maximum 0.20% accuracy decrease, and on the CIFAR-10 image classification task with a maximum of 2.57% accuracy decrease as compared to non-FL counterparts.
{"title":"Chain FL: Decentralized Federated Machine Learning via Blockchain","authors":"Caner Korkmaz, Halil Eralp Kocas, Ahmet Uysal, Ahmed Masry, O. Ozkasap, Barış Akgün","doi":"10.1109/BCCA50787.2020.9274451","DOIUrl":"https://doi.org/10.1109/BCCA50787.2020.9274451","url":null,"abstract":"Federated learning is a collaborative machine learning mechanism that allows multiple parties to develop a model without sharing the training data. It is a promising mechanism since it empowers collaboration in fields such as medicine and banking where data sharing is not favorable due to legal, technical, ethical, or safety issues without significantly sacrificing accuracy. In centralized federated learning, there is a single central server, and hence it has a single point of failure. Unlike centralized federated learning, decentralized federated learning does not depend on a single central server for the updates. In this paper, we propose a decentralized federated learning approach named Chain FL that makes use of the blockchain to delegate the responsibility of storing the model to the nodes on the network instead of a centralized server. Chain FL produced promising results on the MNIST digit recognition task with a maximum 0.20% accuracy decrease, and on the CIFAR-10 image classification task with a maximum of 2.57% accuracy decrease as compared to non-FL counterparts.","PeriodicalId":218474,"journal":{"name":"2020 Second International Conference on Blockchain Computing and Applications (BCCA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133249807","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 : 2020-11-02DOI: 10.1109/BCCA50787.2020.9274458
Mirko Staderini, Caterina Palli, A. Bondavalli
Blockchain technology is having an ever-increasing impact on distributed applications domain, since the adoption of Blockchain 2.0 led to the spread of smart contracts. In such a context, Ethereum is the framework with the highest diffusion in terms of smart contract’s development, with a consequent rise of exploitation of code vulnerabilities, some of which causing bad financial losses. For this reason, this paper focuses on the issues of Ethereum smart contracts implementation (made with the Turing-complete language Solidity), providing a comprehensive systematization of such vulnerabilities basing on a slice of the Common Weakness Enumeration (CWE). Moreover, some relevant propagation cases among different vulnerabilities and CWE groups, observed in exploited contracts, are highlighted.
{"title":"Classification of Ethereum Vulnerabilities and their Propagations","authors":"Mirko Staderini, Caterina Palli, A. Bondavalli","doi":"10.1109/BCCA50787.2020.9274458","DOIUrl":"https://doi.org/10.1109/BCCA50787.2020.9274458","url":null,"abstract":"Blockchain technology is having an ever-increasing impact on distributed applications domain, since the adoption of Blockchain 2.0 led to the spread of smart contracts. In such a context, Ethereum is the framework with the highest diffusion in terms of smart contract’s development, with a consequent rise of exploitation of code vulnerabilities, some of which causing bad financial losses. For this reason, this paper focuses on the issues of Ethereum smart contracts implementation (made with the Turing-complete language Solidity), providing a comprehensive systematization of such vulnerabilities basing on a slice of the Common Weakness Enumeration (CWE). Moreover, some relevant propagation cases among different vulnerabilities and CWE groups, observed in exploited contracts, are highlighted.","PeriodicalId":218474,"journal":{"name":"2020 Second International Conference on Blockchain Computing and Applications (BCCA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131528683","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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