Pub Date : 2021-09-08DOI: 10.14279/TUJ.ECEASST.80.1162
Salil Sharma, E. Al-khannaq, R. Riebl, W. Schakel, P. Knoppers, A. Verbraeck, J. V. Lint
Truck platooning is an application of cooperative adaptive cruise control (CACC) which relies on vehicle-to-vehicle communications facilitated by vehicle ad-hoc networks. Communication uncertainties can affect the performance of a CACC controller. Previous research has not considered the full spectrum of possible car-following scenarios needed to understand how the longitudinal behaviour of truck platoons would be affected by changes in the communication network. In this paper, we investigate the impact of radio channel parameters on the string stability and collision avoidance capabilities of a CACC controller governing the longitudinal behaviour of truck platoons in a majority of critical car-following situations. We develop and use a novel, sophisticated and open-source VANET simulator OTS-Artery, which brings microscopic traffic simulation, network simulation, and psychological concepts in a single environment, for our investigations. Our results indicate that string stability and safety of truck platoons are mostly affected in car-following situations where truck platoons accelerate from the standstill to the maximum speed and decelerate from the maximum speed down to the standstill. The findings suggest that string stability can be improved by increasing transmission power and lowering receiver sensitivity. However, the safety of truck platoons seems to be sensitive to the choice of the path loos model.
{"title":"Impact of radio channel characteristics on the longitudinal behaviour of truck platoons in critical car-following situations","authors":"Salil Sharma, E. Al-khannaq, R. Riebl, W. Schakel, P. Knoppers, A. Verbraeck, J. V. Lint","doi":"10.14279/TUJ.ECEASST.80.1162","DOIUrl":"https://doi.org/10.14279/TUJ.ECEASST.80.1162","url":null,"abstract":"Truck platooning is an application of cooperative adaptive cruise control (CACC) which relies on vehicle-to-vehicle communications facilitated by vehicle ad-hoc networks. Communication uncertainties can affect the performance of a CACC controller. Previous research has not considered the full spectrum of possible car-following scenarios needed to understand how the longitudinal behaviour of truck platoons would be affected by changes in the communication network. In this paper, we investigate the impact of radio channel parameters on the string stability and collision avoidance capabilities of a CACC controller governing the longitudinal behaviour of truck platoons in a majority of critical car-following situations. We develop and use a novel, sophisticated and open-source VANET simulator OTS-Artery, which brings microscopic traffic simulation, network simulation, and psychological concepts in a single environment, for our investigations. Our results indicate that string stability and safety of truck platoons are mostly affected in car-following situations where truck platoons accelerate from the standstill to the maximum speed and decelerate from the maximum speed down to the standstill. The findings suggest that string stability can be improved by increasing transmission power and lowering receiver sensitivity. However, the safety of truck platoons seems to be sensitive to the choice of the path loos model.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130048413","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 : 2021-09-08DOI: 10.14279/TUJ.ECEASST.80.1157
August See
Web Robots (bots) that automate communication with a service on the Internet via their API are efficient and easy to scale. A large number of bots leads to significant losses for providers and can frustrate users of social media, games or online stores. Existing solutions such as CAPTCHAs or complex registrations either frustrate users or are easy to circumvent. Current solutions that make it difficult to create bots are only effective for the first bot. Once the first bot is created, it can be easily duplicated to build an army of bots. This paper presents an approach inspired by polymorphic malware and censorship resistance to change this. Each client that communicates with a service does so by using its own application protocol that is syntactically different but not semantically. Thus, a bot creator is forced to either find a way to automatically extract the whole application protocol from a client or to reverse engineer a new protocol for each bot that is created.
{"title":"Polymorphic Protocols for Fighting Bots","authors":"August See","doi":"10.14279/TUJ.ECEASST.80.1157","DOIUrl":"https://doi.org/10.14279/TUJ.ECEASST.80.1157","url":null,"abstract":"Web Robots (bots) that automate communication with a service on the Internet via their API are efficient and easy to scale. A large number of bots leads to significant losses for providers and can frustrate users of social media, games or online stores. Existing solutions such as CAPTCHAs or complex registrations either frustrate users or are easy to circumvent. Current solutions that make it difficult to create bots are only effective for the first bot. Once the first bot is created, it can be easily duplicated to build an army of bots. This paper presents an approach inspired by polymorphic malware and censorship resistance to change this. Each client that communicates with a service does so by using its own application protocol that is syntactically different but not semantically. Thus, a bot creator is forced to either find a way to automatically extract the whole application protocol from a client or to reverse engineer a new protocol for each bot that is created.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131584551","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 : 2021-09-08DOI: 10.14279/TUJ.ECEASST.80.1148
Daniel Spiekermann, Jörg Keller
Nowadays IT infrastructures have to supply a flexible and dynamic platform for the provision of modern applications. Kubernetes is one of the most notable environments for the provisioning of small and independently running microservices used by modern applications. With Kubernetes, these microservices can be developed, deployed, updated and scaled in a continuous process. This flexibility is a huge advantage to older and more static environments. But whereas these old infrastructures lack in dynamics, necessary digital investigation are easier to accomplish. This need is still existing in modern environments, hence this paper presents a novel approach for the lawful interception of network packets in a Kubernetes cluster. The approach improves the dynamic capture processes by monitoring involved devices assigned to a defined application without hampering the environment or capturing unwanted network packets. Keywords: Kubernetes, network
{"title":"Wiretapping Pods and Nodes - Lawful Interception in Kubernetes","authors":"Daniel Spiekermann, Jörg Keller","doi":"10.14279/TUJ.ECEASST.80.1148","DOIUrl":"https://doi.org/10.14279/TUJ.ECEASST.80.1148","url":null,"abstract":"Nowadays IT infrastructures have to supply a flexible and dynamic platform for the provision of modern applications. Kubernetes is one of the most notable environments for the provisioning of small and independently running microservices used by modern applications. With Kubernetes, these microservices can be developed, deployed, updated and scaled in a continuous process. This flexibility is a huge advantage to older and more static environments. But whereas these old infrastructures lack in dynamics, necessary digital investigation are easier to accomplish. This need is still existing in modern environments, hence this paper presents a novel approach for the lawful interception of network packets in a Kubernetes cluster. The approach improves the dynamic capture processes by monitoring involved devices assigned to a defined application without hampering the environment or capturing unwanted network packets. Keywords: Kubernetes, network","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132760458","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 : 2021-09-08DOI: 10.14279/TUJ.ECEASST.80.1165.1083
Andrés Marín López, Patricia Arias Cabarcos, T. Strufe, Gabriel Barceló-Soteras, Florina Almenárez Mendoza, Daniel Díaz Sánchez
Securing DNS in Edge- and Fog computing, or other scenarios where microservices are offloaded, requires the provision of zone signing keys to the third parties who control the computing infrastructure. This fundamentally allows the infrastructure provider to create novel signatures at their discretion and even arbitrarily extend the certificate chain. Based on our proposal on soft delegation for DNSSEC, which curtails this vulnerability, we report on our proof-of-concept: a C-implementation of chameleon hashes in OpenSSL, a server side implementation of the mechanism in the ldns server, and an offline client that validates the signed records, in this paper. We also discuss different approaches for generating DNSSEC RRSIG records, and the behavior of a resolver to verify the credentials and securely connect to an end point using TLS with SNI and DANE.
{"title":"Implementing DNSSEC soft delegation for microservices","authors":"Andrés Marín López, Patricia Arias Cabarcos, T. Strufe, Gabriel Barceló-Soteras, Florina Almenárez Mendoza, Daniel Díaz Sánchez","doi":"10.14279/TUJ.ECEASST.80.1165.1083","DOIUrl":"https://doi.org/10.14279/TUJ.ECEASST.80.1165.1083","url":null,"abstract":"Securing DNS in Edge- and Fog computing, or other scenarios where microservices are offloaded, requires the provision of zone signing keys to the third parties who control the computing infrastructure. This fundamentally allows the infrastructure provider to create novel signatures at their discretion and even arbitrarily extend the certificate chain. Based on our proposal on soft delegation for DNSSEC, which curtails this vulnerability, we report on our proof-of-concept: a C-implementation of chameleon hashes in OpenSSL, a server side implementation of the mechanism in the ldns server, and an offline client that validates the signed records, in this paper. We also discuss different approaches for generating DNSSEC RRSIG records, and the behavior of a resolver to verify the credentials and securely connect to an end point using TLS with SNI and DANE.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122043699","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 : 2021-09-08DOI: 10.14279/TUJ.ECEASST.80.1130.1081
Lucas Pacheco, D. Rosário, Eduadro Cerqueira, T. Braun
Federated Learning (FL) is one of the leading learning paradigms for enabling a more significant presence of intelligent applications in networking considering highly distributed environments while preserving user privacy. However, FL has the significant shortcoming of requiring user data to be Independent Identically Distributed (IID) to make reliable predictions for a given group of users. We present a Neural Network-based Federated Clustering mechanism capable of clustering the local models trained by users of the network with no access to their raw data. We also present an alternative to the FedAvg aggregation algorithm used in traditional FL, which significantly increases the aggregated models' reliability in Mean Square Error by creating several training models over IID users.
{"title":"Federated User Clustering for non-IID Federated Learning","authors":"Lucas Pacheco, D. Rosário, Eduadro Cerqueira, T. Braun","doi":"10.14279/TUJ.ECEASST.80.1130.1081","DOIUrl":"https://doi.org/10.14279/TUJ.ECEASST.80.1130.1081","url":null,"abstract":"Federated Learning (FL) is one of the leading learning paradigms for enabling a more significant presence of intelligent applications in networking considering highly distributed environments while preserving user privacy. However, FL has the significant shortcoming of requiring user data to be Independent Identically Distributed (IID) to make reliable predictions for a given group of users. We present a Neural Network-based Federated Clustering mechanism capable of clustering the local models trained by users of the network with no access to their raw data. We also present an alternative to the FedAvg aggregation algorithm used in traditional FL, which significantly increases the aggregated models' reliability in Mean Square Error by creating several training models over IID users.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124119036","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 : 2021-09-08DOI: 10.14279/TUJ.ECEASST.80.1144
Daniil Romanchenko, Matis Tartie, Ba Que Le, J. T. Gómez, F. Dressler
Molecular Communication (MC) is a new paradigm for communication processes with a variety of applications such as health care and industrial sectors. The rapid development of MC, with the support of testbeds and simulators, requires scalable modeling tools. In this paper, we propose a f ield-programmable gate array (FPGA) design-based approach for the emission, diffusion, and reception of molecules. Results exhibit a close correspondence to state of the art analytical modeling of MC processes.
{"title":"Molecular Communication Channel Modelling in FPGA Technology","authors":"Daniil Romanchenko, Matis Tartie, Ba Que Le, J. T. Gómez, F. Dressler","doi":"10.14279/TUJ.ECEASST.80.1144","DOIUrl":"https://doi.org/10.14279/TUJ.ECEASST.80.1144","url":null,"abstract":"Molecular Communication (MC) is a new paradigm for communication processes with a variety of applications such as health care and industrial sectors. The rapid development of MC, with the support of testbeds and simulators, requires scalable modeling tools. In this paper, we propose a f ield-programmable gate array (FPGA) design-based approach for the emission, diffusion, and reception of molecules. Results exhibit a close correspondence to state of the art analytical modeling of MC processes.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126470410","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 : 2021-09-08DOI: 10.14279/TUJ.ECEASST.80.1185
Marco Häberle, Benjamin Steinert, M. Menth
Taking care of security is a crucial task for every operator of a campus network. One of the most fundamental security-related network functions that can be found in most networks for this purpose are stateful firewalls. However, deploying firewalls in large campus networks, e.g., at a university, can be challenging. Hardware appliances that can cope with today's high data rates at the border of a campus network are not cost-effective enough for most deployments. Shifting the responsibility to run firewalls to single departments at a university is not feasible because the expertise to manage these devices is not available there. For this reason, we propose a cloud-like infrastructure based on service function chaining (SFC) and network function virtualization (NFV) that allows users to deploy network functions like firewalls at a central place while hiding most technical details from the users.
{"title":"Firewall-as-a-Service for Campus Networks Based on P4-SFC","authors":"Marco Häberle, Benjamin Steinert, M. Menth","doi":"10.14279/TUJ.ECEASST.80.1185","DOIUrl":"https://doi.org/10.14279/TUJ.ECEASST.80.1185","url":null,"abstract":"Taking care of security is a crucial task for every operator of a campus network. One of the most fundamental security-related network functions that can be found in most networks for this purpose are stateful firewalls. However, deploying firewalls in large campus networks, e.g., at a university, can be challenging. Hardware appliances that can cope with today's high data rates at the border of a campus network are not cost-effective enough for most deployments. Shifting the responsibility to run firewalls to single departments at a university is not feasible because the expertise to manage these devices is not available there. For this reason, we propose a cloud-like infrastructure based on service function chaining (SFC) and network function virtualization (NFV) that allows users to deploy network functions like firewalls at a central place while hiding most technical details from the users.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116866630","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 : 2021-09-08DOI: 10.14279/TUJ.ECEASST.80.1134.1078
Birte Friesel, O. Spinczyk
IoT devices rely on data exchange with gateways and cloud servers. However, the performance of today's serialization formats and libraries on embedded systems with energy and memory constraints is not well-documented and hard to predict. We evaluate (de)serialization and transmission cost of mqtt.eclipse.org payloads on 8- to 32-bit microcontrollers and find that Protocol Buffers (as implemented by NanoPB) and the XDR format, dating back to 1987, are most efficient.
{"title":"Data Serialization Formats for the Internet of Things","authors":"Birte Friesel, O. Spinczyk","doi":"10.14279/TUJ.ECEASST.80.1134.1078","DOIUrl":"https://doi.org/10.14279/TUJ.ECEASST.80.1134.1078","url":null,"abstract":"IoT devices rely on data exchange with gateways and cloud servers. However, the performance of today's serialization formats and libraries on embedded systems with energy and memory constraints is not well-documented and hard to predict. We evaluate (de)serialization and transmission cost of mqtt.eclipse.org payloads on 8- to 32-bit microcontrollers and find that Protocol Buffers (as implemented by NanoPB) and the XDR format, dating back to 1987, are most efficient.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121614004","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 : 2020-01-07DOI: 10.14279/tuj.eceasst.78.1089
Tim Tegeler, Jonas Schürmann
In general software projects still, have a very high failure rate. We noticed that one of our projects did not gather pace. It was delayed from the beginning and on the way to fail. After investigating the development process, we located the issue in the chosen architecture of the software. Although the used technology has many advantages, it handicapped the application developers by the cumbersome architecture. The challenge was how we could keep the advantages, but simplify the work of the application developers. We came up with the approach to build a toolkit and family of dedicated Domain-Specific Languages which is developed alongside the project. We called it Evolve, and it is built upon the Language-Driven Engineering paradigm. We were able to salvage the project and establish Evolve in the development process of related applications. With Evolve we successfully brought Language-Driven Engineering to industrial practice. It will play a major role in our future software development.
{"title":"Evolve: Language-Driven Engineering in Industrial Practice","authors":"Tim Tegeler, Jonas Schürmann","doi":"10.14279/tuj.eceasst.78.1089","DOIUrl":"https://doi.org/10.14279/tuj.eceasst.78.1089","url":null,"abstract":"In general software projects still, have a very high failure rate. We noticed that one of our projects did not gather pace. It was delayed from the beginning and on the way to fail. After investigating the development process, we located the issue in the chosen architecture of the software. Although the used technology has many advantages, it handicapped the application developers by the cumbersome architecture. The challenge was how we could keep the advantages, but simplify the work of the application developers. We came up with the approach to build a toolkit and family of dedicated Domain-Specific Languages which is developed alongside the project. We called it Evolve, and it is built upon the Language-Driven Engineering paradigm. We were able to salvage the project and establish Evolve in the development process of related applications. With Evolve we successfully brought Language-Driven Engineering to industrial practice. It will play a major role in our future software development.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121853842","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 : 2019-12-16DOI: 10.14279/tuj.eceasst.78.1099
Karl-Falco Storm, Paul Hochrein, P. Engel, A. Rausch
Maneuver and driving style detection are of ongoing interest for the extension of vehicle's functionalities. Existing machine learning approaches require extensive sensor data and demand for high computational power. For vehicle onboard implementation, poorly generalizing rule-based approaches are currently state of the art. Not being restricted to neither comprehensive environmental sensors like camera or radar, nor high computing power (both of what is today only present in upper class' vehicles), our approach allows for cross-vehicle use: In this work, the applicability of small artificial neural networks (ANN) as efficient detectors is tested using a prototypal vehicle implementation. During test drives, overtaking maneuvers have been detected 1.2 s prior to the competing rule-based approach in average, also greatly improving the detection performance. Regarding driving style recognition, ANN-based results are closer to targets and more patient at driving style transitions. A recognition rate of over 75 % is achieved.
{"title":"Applicability of Neural Networks for Driving Style Classification and Maneuver Detection","authors":"Karl-Falco Storm, Paul Hochrein, P. Engel, A. Rausch","doi":"10.14279/tuj.eceasst.78.1099","DOIUrl":"https://doi.org/10.14279/tuj.eceasst.78.1099","url":null,"abstract":"Maneuver and driving style detection are of ongoing interest for the extension of vehicle's functionalities. Existing machine learning approaches require extensive sensor data and demand for high computational power. For vehicle onboard implementation, poorly generalizing rule-based approaches are currently state of the art. Not being restricted to neither comprehensive environmental sensors like camera or radar, nor high computing power (both of what is today only present in upper class' vehicles), our approach allows for cross-vehicle use: In this work, the applicability of small artificial neural networks (ANN) as efficient detectors is tested using a prototypal vehicle implementation. During test drives, overtaking maneuvers have been detected 1.2 s prior to the competing rule-based approach in average, also greatly improving the detection performance. Regarding driving style recognition, ANN-based results are closer to targets and more patient at driving style transitions. A recognition rate of over 75 % is achieved.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116772349","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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