There is a trend towards communication of larger data objects in wireless vehicle communication. In many cases, communication uses publish-subscribe protocols. Data rate requirements of such protocols are best addressed by wireless multicast protocols, but the existing protocols lack an error protection that is suitable for real-time and safety-critical applications. We present an application-aware protocol that supports the popular DDS (Data Distribution Service) middleware. By exploiting data object deadlines and slack for retransmissions and employing an adaptable, multicast-aware prioritization mechanism the reliable exchange of large data objects is enabled. The protocol is sufficiently general to be used on top of different communication standards such as 802.11- and cellular-based V2X (Vehicle-to-Everything) technologies. The protocol was implemented in an OMNeT++ simulation model and evaluated against recent state-of-the-art alternatives using parameters and constraints taken from a motivational truck platooning example. Furthermore, the protocol was implemented using an open-source DDS implementation as the basis and tested on a physical wireless demonstrator setup. The evaluation shows that the presented multicast protocol substantially outperforms the alternatives keeping streaming applications operational even under high frame error rates.
{"title":"An Error Protection Protocol for the Multicast Transmission of Data Samples in V2X Applications","authors":"Alex Bendrick, Jonas Peeck, Rolf Ernst","doi":"10.1145/3617126","DOIUrl":"https://doi.org/10.1145/3617126","url":null,"abstract":"There is a trend towards communication of larger data objects in wireless vehicle communication. In many cases, communication uses publish-subscribe protocols. Data rate requirements of such protocols are best addressed by wireless multicast protocols, but the existing protocols lack an error protection that is suitable for real-time and safety-critical applications. We present an application-aware protocol that supports the popular DDS (Data Distribution Service) middleware. By exploiting data object deadlines and slack for retransmissions and employing an adaptable, multicast-aware prioritization mechanism the reliable exchange of large data objects is enabled. The protocol is sufficiently general to be used on top of different communication standards such as 802.11- and cellular-based V2X (Vehicle-to-Everything) technologies. The protocol was implemented in an OMNeT++ simulation model and evaluated against recent state-of-the-art alternatives using parameters and constraints taken from a motivational truck platooning example. Furthermore, the protocol was implemented using an open-source DDS implementation as the basis and tested on a physical wireless demonstrator setup. The evaluation shows that the presented multicast protocol substantially outperforms the alternatives keeping streaming applications operational even under high frame error rates.","PeriodicalId":7055,"journal":{"name":"ACM Transactions on Cyber-Physical Systems","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46740464","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}
Cooperative Adaptive Cruise Control (CACC) based vehicle platooning can increase safety and efficiency of traffics. This work looks into the communication and control problems of vehicle platooning, and proposes a control and communication co-design for CACC. First, an integrated radar system is presented. This system integrates sensing of relative position, speed, and communication between a predecessor and its follower. Second, a working scheme for the integrated radar system is presented. This scheme allows the radar systems to switch periodically between different working modes without interferences from other modes. Therefore, the relative position, speed, and communication can be asynchronously periodically updated to the controller. Third, a periodic event-triggered control approach is presented. This approach allows asynchronous periodic sampling of the output, and is deeply co-designed with the radar system and its working scheme. Delays are also considered in the control approach. The co-design CACC approach can guarantee the vehicle platoons to be string stable. Numerical example has shown the feasibility of the approach.
{"title":"Periodic Event-Triggered Cooperative Adaptive Cruise Control and Communication Co-Design for Vehicle Platooning","authors":"A. Fu, Sijia Chen, Jun-Li Qiao, Chengpu Yu","doi":"10.1145/3617125","DOIUrl":"https://doi.org/10.1145/3617125","url":null,"abstract":"Cooperative Adaptive Cruise Control (CACC) based vehicle platooning can increase safety and efficiency of traffics. This work looks into the communication and control problems of vehicle platooning, and proposes a control and communication co-design for CACC. First, an integrated radar system is presented. This system integrates sensing of relative position, speed, and communication between a predecessor and its follower. Second, a working scheme for the integrated radar system is presented. This scheme allows the radar systems to switch periodically between different working modes without interferences from other modes. Therefore, the relative position, speed, and communication can be asynchronously periodically updated to the controller. Third, a periodic event-triggered control approach is presented. This approach allows asynchronous periodic sampling of the output, and is deeply co-designed with the radar system and its working scheme. Delays are also considered in the control approach. The co-design CACC approach can guarantee the vehicle platoons to be string stable. Numerical example has shown the feasibility of the approach.","PeriodicalId":7055,"journal":{"name":"ACM Transactions on Cyber-Physical Systems","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45757904","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}
Cyber-Physical Systems (CPS) are increasingly used in many complex applications, such as autonomous delivery drones, the automotive CPS design, power grid control systems, and medical robotics. However, existing programming languages lack certain design patterns for CPS designs, including temporal semantics and concurrency models. Future research directions may involve programming language extensions to support CPS designs. On the other hand, JSF++, MISRA, and MISRA C++ are providing specifications intended to increase the reliability of safety-critical systems. This article also describes the development of rule checkers based on the MISRA C++ specification using the Clang open-source tool, which allows for the annotation of code and the easy extension of the MISRA C++ specification to other programming languages and systems. This is potentially useful for future CPS language research extensions to work with reliability software specifications using the Clang tool. Experiments were performed using key C++ benchmarks to validate our method in comparison with the well-known Coverity commercial tool. We illustrate key rules related to class, inheritance, template, overloading, and exception handling. Open-source benchmarks that violate the rules detected by our checkers are also illustrated. A random graph generator is further used to generate diamond case with multiple inheritance testdata for our software validations. The experimental results demonstrate that our method can provide information that is more detailed than that obtained using Coverity for nine open-source C++ benchmarks. Since the Clang tool is widely used, it will further allow developers to annotate their own extensions.
{"title":"The Support of MISRA C++ Analyzer for Reliability of Embedded Systems","authors":"Che-Chia Lin, Wei-Hsu Chu, Chia-Hsuan Chang, Hui-Hsin Liao, Chun-Chieh Yang, Jenq-Kuen Lee, Yi-Ping You, Tien-Yuan Hsieh","doi":"10.1145/3611390","DOIUrl":"https://doi.org/10.1145/3611390","url":null,"abstract":"Cyber-Physical Systems (CPS) are increasingly used in many complex applications, such as autonomous delivery drones, the automotive CPS design, power grid control systems, and medical robotics. However, existing programming languages lack certain design patterns for CPS designs, including temporal semantics and concurrency models. Future research directions may involve programming language extensions to support CPS designs. On the other hand, JSF++, MISRA, and MISRA C++ are providing specifications intended to increase the reliability of safety-critical systems. This article also describes the development of rule checkers based on the MISRA C++ specification using the Clang open-source tool, which allows for the annotation of code and the easy extension of the MISRA C++ specification to other programming languages and systems. This is potentially useful for future CPS language research extensions to work with reliability software specifications using the Clang tool. Experiments were performed using key C++ benchmarks to validate our method in comparison with the well-known Coverity commercial tool. We illustrate key rules related to class, inheritance, template, overloading, and exception handling. Open-source benchmarks that violate the rules detected by our checkers are also illustrated. A random graph generator is further used to generate diamond case with multiple inheritance testdata for our software validations. The experimental results demonstrate that our method can provide information that is more detailed than that obtained using Coverity for nine open-source C++ benchmarks. Since the Clang tool is widely used, it will further allow developers to annotate their own extensions.","PeriodicalId":7055,"journal":{"name":"ACM Transactions on Cyber-Physical Systems","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44241995","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}
To realize the grand vision of automated driving in smart vehicle cyber-physical systems (CPS), one important task is to support the merging of connected automated vehicles (CAVs) from a metered-ramp to highway. Certain safety rules must be guaranteed. However, this demand is complicated by the inherently unreliable wireless communications. In this paper, we focus on the well adopted constant-time-headway (CTH) safety rule. We propose a highway and metered-ramp CAV collaborative merging protocol, and formally prove its guarantee of the CTH safety and liveness under arbitrary wireless data packet losses. These theoretical claims are further validated by our simulations. Furthermore, the simulation results also show significant improvements on the merging efficiency over other solution alternatives. Particularly, the merging success rates are more than (99% ) better in 11 out of 18 comparison pairs, and (0% ) (i.e. tied) (sim 71% ) better in the remaining 7 comparison pairs.
{"title":"A Reliable Wireless Protocol for Highway and Metered-Ramp CAV Collaborative Merging with Constant-Time-Headway Safety Guarantee","authors":"Xueli Fan, Qixin Wang, Jie Liu","doi":"10.1145/3609227","DOIUrl":"https://doi.org/10.1145/3609227","url":null,"abstract":"To realize the grand vision of automated driving in smart vehicle cyber-physical systems (CPS), one important task is to support the merging of connected automated vehicles (CAVs) from a metered-ramp to highway. Certain safety rules must be guaranteed. However, this demand is complicated by the inherently unreliable wireless communications. In this paper, we focus on the well adopted constant-time-headway (CTH) safety rule. We propose a highway and metered-ramp CAV collaborative merging protocol, and formally prove its guarantee of the CTH safety and liveness under arbitrary wireless data packet losses. These theoretical claims are further validated by our simulations. Furthermore, the simulation results also show significant improvements on the merging efficiency over other solution alternatives. Particularly, the merging success rates are more than (99% ) better in 11 out of 18 comparison pairs, and (0% ) (i.e. tied) (sim 71% ) better in the remaining 7 comparison pairs.","PeriodicalId":7055,"journal":{"name":"ACM Transactions on Cyber-Physical Systems","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47616394","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}
Ertem Esiner, Utku Tefek, D. Mashima, Binbin Chen, Z. Kalbarczyk, D. Nicol
Successful attacks against industrial control systems (ICS) often exploit insufficient checking mechanisms. While firewalls, intrusion detection systems, and similar appliances introduce essential checks, their efficacy depends on the attackers’ ability to bypass such middleboxes. We propose a provenance solution to enable the verification of end-to-end message delivery path and the actions performed on a message. Fast and flexible provenance verification (F2-Pro) provides cryptographically verifiable evidence that a message has originated from a legitimate source and gone through the necessary checks before reaching its destination. F2-Pro relies on lightweight cryptographic primitives and flexibly supports various communication settings and protocols encountered in ICS thanks to its transparent, bump-in-the-wire design. We provide formal definitions and cryptographically prove F2-Pro ’s security. For human interaction with ICS via a field service device, F2-Pro features a multi-factor authentication mechanism that starts the provenance chain from a human user issuing commands. We compatibility tested F2-Pro on a smart power grid testbed and reported a sub-millisecond latency overhead per communication hop using a modest ARM Cortex-A15 processor.
{"title":"Message Authentication and Provenance Verification for Industrial Control Systems","authors":"Ertem Esiner, Utku Tefek, D. Mashima, Binbin Chen, Z. Kalbarczyk, D. Nicol","doi":"10.1145/3607194","DOIUrl":"https://doi.org/10.1145/3607194","url":null,"abstract":"Successful attacks against industrial control systems (ICS) often exploit insufficient checking mechanisms. While firewalls, intrusion detection systems, and similar appliances introduce essential checks, their efficacy depends on the attackers’ ability to bypass such middleboxes. We propose a provenance solution to enable the verification of end-to-end message delivery path and the actions performed on a message. Fast and flexible provenance verification (F2-Pro) provides cryptographically verifiable evidence that a message has originated from a legitimate source and gone through the necessary checks before reaching its destination. F2-Pro relies on lightweight cryptographic primitives and flexibly supports various communication settings and protocols encountered in ICS thanks to its transparent, bump-in-the-wire design. We provide formal definitions and cryptographically prove F2-Pro ’s security. For human interaction with ICS via a field service device, F2-Pro features a multi-factor authentication mechanism that starts the provenance chain from a human user issuing commands. We compatibility tested F2-Pro on a smart power grid testbed and reported a sub-millisecond latency overhead per communication hop using a modest ARM Cortex-A15 processor.","PeriodicalId":7055,"journal":{"name":"ACM Transactions on Cyber-Physical Systems","volume":"1 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41797627","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 paper presents an approach for model extraction, formal specification, verification and repair of the scheduler of Contiki, which is an event-driven lightweight Operating System for the Internet of Things (IoT). We first derive a state machine-based abstraction of the scheduler’s modes of operation along with the control flow abstractions of the scheduler’s most important functions. We then use a set of transformation rules to formally specify the scheduler and all its internal functions in Promela. Additional contributions with respect to the conference version of this article include (1) modeling nested function calls in the Promela model of the scheduler using a novel technique amenable to model checking in SPIN; (2) modeling protothreads in Promela; (3) specifying and formally verifying twelve critical requirements of the scheduler; (4) detecting new design flaws in Contiki’s scheduler, for the first time (to the best of our knowledge); (5) repairing the model and the source code of Contiki’s scheduler towards fixing the flaws detected through verification, as well as regression verification of the entire model of the scheduler, and (6) experimentally analyzing the time and space costs of verification before and after repair. The proposed formal model of Contiki’s scheduler along with novel modeling techniques enhance our knowledge regarding the most critical components of Contiki, and provide reusable methods for formal specification and verification of other event-driven operating systems used in Cyber Physical Systems (CPS) and IoT.
{"title":"Formal Specification, Verification and Repair of Contiki’s Scheduler","authors":"Hassan Mousavi, Ali Ebnenasir, E. Mahmoudzadeh","doi":"10.1145/3605948","DOIUrl":"https://doi.org/10.1145/3605948","url":null,"abstract":"This paper presents an approach for model extraction, formal specification, verification and repair of the scheduler of Contiki, which is an event-driven lightweight Operating System for the Internet of Things (IoT). We first derive a state machine-based abstraction of the scheduler’s modes of operation along with the control flow abstractions of the scheduler’s most important functions. We then use a set of transformation rules to formally specify the scheduler and all its internal functions in Promela. Additional contributions with respect to the conference version of this article include (1) modeling nested function calls in the Promela model of the scheduler using a novel technique amenable to model checking in SPIN; (2) modeling protothreads in Promela; (3) specifying and formally verifying twelve critical requirements of the scheduler; (4) detecting new design flaws in Contiki’s scheduler, for the first time (to the best of our knowledge); (5) repairing the model and the source code of Contiki’s scheduler towards fixing the flaws detected through verification, as well as regression verification of the entire model of the scheduler, and (6) experimentally analyzing the time and space costs of verification before and after repair. The proposed formal model of Contiki’s scheduler along with novel modeling techniques enhance our knowledge regarding the most critical components of Contiki, and provide reusable methods for formal specification and verification of other event-driven operating systems used in Cyber Physical Systems (CPS) and IoT.","PeriodicalId":7055,"journal":{"name":"ACM Transactions on Cyber-Physical Systems","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47497163","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}
T. Zoppi, Innocenzo Mungiello, A. Ceccarelli, Alberto Cirillo, Lorenzo Sarti, Lorenzo Esposito, G. Scaglione, Sergio Repetto, A. Bondavalli
The railway domain is regulated by rigorous safety standards to ensure that specific safety goals are met. Often, safety-critical systems rely on custom hardware-software components that are built from scratch to achieve specific functional and non-functional requirements. Instead, the (partial) usage of Commercial Off-The-Shelf (COTS) components is very attractive as it potentially allows reducing cost and time to market. Unfortunately, COTS components do not individually offer enough guarantees in terms of safety and security to be used in critical systems as they are. In such a context, RFI (Rete Ferroviaria Italiana), a major player in Europe for railway infrastructure management, aims at equipping track-side workers with COTS devices to remotely and safely interact with the existing interlocking system, drastically improving the performance of maintenance operations. This paper describes the first effort to update existing (embedded) railway systems to a more recent cyber-physical system paradigm. Our Remote Worker Dashboard (RWD) pairs the existing safe interlocking machinery alongside COTS mobile components, making cyber and physical components cooperate to provide the user with responsive, safe, and secure service. Specifically, the RWD is a SIL4 cyber-physical system to support maintenance of actuators and railways in which COTS mobile devices are safely used by track-side workers. The concept, development, implementation, verification and validation activities to build the RWD were carried out in compliance with the applicable CENELEC standards required by certification bodies to declare compliance with specific guidelines.
{"title":"Safe Maintenance of Railways using COTS Mobile Devices: The Remote Worker Dashboard","authors":"T. Zoppi, Innocenzo Mungiello, A. Ceccarelli, Alberto Cirillo, Lorenzo Sarti, Lorenzo Esposito, G. Scaglione, Sergio Repetto, A. Bondavalli","doi":"10.1145/3607193","DOIUrl":"https://doi.org/10.1145/3607193","url":null,"abstract":"The railway domain is regulated by rigorous safety standards to ensure that specific safety goals are met. Often, safety-critical systems rely on custom hardware-software components that are built from scratch to achieve specific functional and non-functional requirements. Instead, the (partial) usage of Commercial Off-The-Shelf (COTS) components is very attractive as it potentially allows reducing cost and time to market. Unfortunately, COTS components do not individually offer enough guarantees in terms of safety and security to be used in critical systems as they are. In such a context, RFI (Rete Ferroviaria Italiana), a major player in Europe for railway infrastructure management, aims at equipping track-side workers with COTS devices to remotely and safely interact with the existing interlocking system, drastically improving the performance of maintenance operations. This paper describes the first effort to update existing (embedded) railway systems to a more recent cyber-physical system paradigm. Our Remote Worker Dashboard (RWD) pairs the existing safe interlocking machinery alongside COTS mobile components, making cyber and physical components cooperate to provide the user with responsive, safe, and secure service. Specifically, the RWD is a SIL4 cyber-physical system to support maintenance of actuators and railways in which COTS mobile devices are safely used by track-side workers. The concept, development, implementation, verification and validation activities to build the RWD were carried out in compliance with the applicable CENELEC standards required by certification bodies to declare compliance with specific guidelines.","PeriodicalId":7055,"journal":{"name":"ACM Transactions on Cyber-Physical Systems","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46807799","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}
Francesco Pollicino, Dario Stabili, Mirco Marchetti
This work presents an experimental evaluation of the detection performance of eight different algorithms for anomaly detection on the Controller Area Network (CAN) bus of modern vehicles based on the analysis of the timing or frequency of CAN messages. This work solves the current limitations of related scientific literature, that is based on private dataset, lacks of open implementations, and detailed description of the detection algorithms. These drawback prevent the reproducibility of published results, and makes it impossible to compare a novel proposal against related work, thus hindering the advancement of science. This paper solves these issues by publicly releasing implementations, labeled datasets and by describing an unbiased experimental comparisons.
{"title":"Performance comparison of timing-based anomaly detectors for Controller Area Network: a reproducible study","authors":"Francesco Pollicino, Dario Stabili, Mirco Marchetti","doi":"10.1145/3604913","DOIUrl":"https://doi.org/10.1145/3604913","url":null,"abstract":"This work presents an experimental evaluation of the detection performance of eight different algorithms for anomaly detection on the Controller Area Network (CAN) bus of modern vehicles based on the analysis of the timing or frequency of CAN messages. This work solves the current limitations of related scientific literature, that is based on private dataset, lacks of open implementations, and detailed description of the detection algorithms. These drawback prevent the reproducibility of published results, and makes it impossible to compare a novel proposal against related work, thus hindering the advancement of science. This paper solves these issues by publicly releasing implementations, labeled datasets and by describing an unbiased experimental comparisons.","PeriodicalId":7055,"journal":{"name":"ACM Transactions on Cyber-Physical Systems","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49426904","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}
Md. Jaminur Islam, J. P. Talusan, Shameek Bhattacharjee, F. Tiausas, Abhishek Dubey, K. Yasumoto, Sajal K. Das
Modern smart cities need smart transportation solutions to quickly detect various traffic emergencies and incidents in the city to avoid cascading traffic disruptions. To materialize this, roadside units and ambient transportation sensors are being deployed to collect speed data that enables the monitoring of traffic conditions on each road segment. In this paper, we first propose a scalable data-driven anomaly-based traffic incident detection framework for a city-scale smart transportation system. Specifically, we propose an incremental region growing approximation algorithm for optimal Spatio-temporal clustering of road segments and their data; such that road segments are strategically divided into highly correlated clusters. The highly correlated clusters enable identifying a Pythagorean Mean-based invariant as an anomaly detection metric that is highly stable under no incidents but shows a deviation in the presence of incidents. We learn the bounds of the invariants in a robust manner such that anomaly detection can generalize to unseen events, even when learning from real noisy data. Second, using cluster-level detection, we propose a folded Gaussian classifier to pinpoint the particular segment in a cluster where the incident happened in an automated manner. We perform extensive experimental validation using mobility data collected from four cities in Tennessee, compare with the state-of-the-art ML methods, to prove that our method can detect incidents within each cluster in real-time and outperforms known ML methods.
{"title":"Scalable Pythagorean Mean based Incident Detection in Smart Transportation Systems","authors":"Md. Jaminur Islam, J. P. Talusan, Shameek Bhattacharjee, F. Tiausas, Abhishek Dubey, K. Yasumoto, Sajal K. Das","doi":"10.1145/3603381","DOIUrl":"https://doi.org/10.1145/3603381","url":null,"abstract":"Modern smart cities need smart transportation solutions to quickly detect various traffic emergencies and incidents in the city to avoid cascading traffic disruptions. To materialize this, roadside units and ambient transportation sensors are being deployed to collect speed data that enables the monitoring of traffic conditions on each road segment. In this paper, we first propose a scalable data-driven anomaly-based traffic incident detection framework for a city-scale smart transportation system. Specifically, we propose an incremental region growing approximation algorithm for optimal Spatio-temporal clustering of road segments and their data; such that road segments are strategically divided into highly correlated clusters. The highly correlated clusters enable identifying a Pythagorean Mean-based invariant as an anomaly detection metric that is highly stable under no incidents but shows a deviation in the presence of incidents. We learn the bounds of the invariants in a robust manner such that anomaly detection can generalize to unseen events, even when learning from real noisy data. Second, using cluster-level detection, we propose a folded Gaussian classifier to pinpoint the particular segment in a cluster where the incident happened in an automated manner. We perform extensive experimental validation using mobility data collected from four cities in Tennessee, compare with the state-of-the-art ML methods, to prove that our method can detect incidents within each cluster in real-time and outperforms known ML methods.","PeriodicalId":7055,"journal":{"name":"ACM Transactions on Cyber-Physical Systems","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43904763","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}
A weakly-hard fault model can be captured by an (m,k) constraint, where 0≤ m≤ k, meaning that there are at most m bad events (faults) among any k consecutive events. In this article, we use a weakly-hard fault model to constrain the occurrences of faults in system inputs. We develop approaches to verify properties for all possible values of (m,k), where k is smaller than or equal to a given K, in an exact and efficient manner. By verifying all possible values of (m,k), we define weakly-hard requirements for the system environment and design a runtime monitor based on counting the number of faults in system inputs. If the system environment satisfies the weakly-hard requirements, then the satisfaction of desired properties is guaranteed; otherwise, the runtime monitor can notify the system to switch to a safe mode. This is especially essential for cyber-physical systems that need to provide guarantees with limited resources and the existence of faults. Experimental results with discrete second-order control, network routing, vehicle following, and lane changing demonstrate the generality and the efficiency of the proposed approaches.
{"title":"System Verification and Runtime Monitoring with Multiple Weakly-Hard Constraints","authors":"Yi-Ting Hsieh, Tzu-Tao Chang, Chen-Jun Tsai, Shih-Lun Wu, C. Bai, Kai-Chieh Chang, Chung-Wei Lin, Eunsuk Kang, Chao Huang, Qi Zhu","doi":"10.1145/3603380","DOIUrl":"https://doi.org/10.1145/3603380","url":null,"abstract":"A weakly-hard fault model can be captured by an (m,k) constraint, where 0≤ m≤ k, meaning that there are at most m bad events (faults) among any k consecutive events. In this article, we use a weakly-hard fault model to constrain the occurrences of faults in system inputs. We develop approaches to verify properties for all possible values of (m,k), where k is smaller than or equal to a given K, in an exact and efficient manner. By verifying all possible values of (m,k), we define weakly-hard requirements for the system environment and design a runtime monitor based on counting the number of faults in system inputs. If the system environment satisfies the weakly-hard requirements, then the satisfaction of desired properties is guaranteed; otherwise, the runtime monitor can notify the system to switch to a safe mode. This is especially essential for cyber-physical systems that need to provide guarantees with limited resources and the existence of faults. Experimental results with discrete second-order control, network routing, vehicle following, and lane changing demonstrate the generality and the efficiency of the proposed approaches.","PeriodicalId":7055,"journal":{"name":"ACM Transactions on Cyber-Physical Systems","volume":"7 1","pages":"1 - 28"},"PeriodicalIF":2.3,"publicationDate":"2023-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47068232","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：