| 1. |
- Akbarian, Fatemeh, et al.
(författare)
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A Security Framework in Digital Twins for Cloud-based Industrial Control Systems: Intrusion Detection and Mitigation
- 2021
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Ingår i: 2021 26th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA ). - 9781728129907 - 9781728129891
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Konferensbidrag (refereegranskat)abstract
- With the help of modern technologies and advances in communication systems, the functionality of Industrial control systems (ICS) has been enhanced leading toward to have more efficient and smarter ICS. However, this makes these systems more and more connected and part of a networked system. This can provide an entry point for attackers to infiltrate the system and cause damage with potentially catastrophic consequences. Therefore, in this paper, we propose a digital twin-based security framework for ICS that consists of two parts: attack detection and attack mitigation. In this framework we deploy an intrusion detection system in digital domain that can detect attacks in a timely manner. Then, using our mitigation method, we keep the system stable with acceptable performance during the attack. Additionally, we implement our framework on a real testbed and evaluate its capability by subjecting it to a set of attacks.
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| 2. |
- Akbarian, Fatemeh, et al.
(författare)
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Attack Resilient Cloud-Based Control Systems for Industry 4.0
- 2023
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Ingår i: IEEE Access. - 2169-3536. ; 11, s. 27865-27882
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Tidskriftsartikel (refereegranskat)abstract
- In recent years, since the cloud can provide tremendous advantages regarding storage and computing resources, the industry has been motivated to move industrial control systems to the cloud. However, the cloud also introduces significant security challenges since moving control systems to the cloud can enable attackers to infiltrate the system and establish an attack that can lead to damages and disruptions with potentially catastrophic consequences. Therefore, some security measures are necessary to detect these attacks in a timely manner and mitigate their impact. In this paper, we propose a security framework for cloud control systems that makes them resilient against attacks. This framework includes three steps: attack detection, attack isolation, and attack mitigation. We validate our proposed framework on a real testbed and evaluate its capability by subjecting it to a set of attacks. We show that our proposed solution can detect an attack in a timely manner and keep the plant stable, with high performance during the attack.
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| 3. |
- Akbarian, Fatemeh, et al.
(författare)
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Demonstration: A cloud-control system equipped with intrusion detection and mitigation
- 2021
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Ingår i: The Conference on Networked Systems (NetSys 2021).
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Konferensbidrag (refereegranskat)abstract
- The cloud control systems (CCs) are inseparable parts of industry 4.0. The cloud, by providing storage and computing resources, allows the controllers to evaluate complex problems that are too computationally demanding to perform locally. However, connecting physical systems to the cloud through the network can provide an entry point for attackers to infiltrate the system and cause damage with potentially catastrophic consequences. Hence, in this paper, we present a demo of our proposed security framework for CCs and demonstrate how it can detect attacks on this system quickly and mitigate them.
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| 4. |
- Akbarian, Fatemeh, et al.
(författare)
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Detecting and Mitigating Actuator Attacks on Cloud Control Systems through Digital Twins
- 2023
-
Ingår i: The 31st International Conference on Software, Telecommunications and Computer Networks (SoftCOM 2023). - 9798350301076
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Konferensbidrag (refereegranskat)abstract
- Recently, the industry has been driven to move industrial control systems to the cloud due to the significant advantages it offers in terms of storage and computing resources. However, this shift also brings forth significant security challenges. By moving control systems to the cloud, the potential for attackers to infiltrate the system and launch damaging attacks increases. These attacks can result in severe disruptions and potentially catastrophic consequences. Hence, attack detection and mitigation mechanisms are crucial for cloud control systems. In this paper, we present an approach that leverages the digital twins concept and virtual actuator method to detect and mitigate deception attacks on control signals within cloud control systems. By conducting experiments on a real testbed and subjecting it to a set of attacks, we validate the effectiveness of our solution. Our proposed method successfully detects attacks in a timely manner and keeps the plant stable, with a good performance during the attack.
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| 5. |
- Akbarian, Fatemeh, et al.
(författare)
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Detection and mitigation of deception attacks on cloud-based industrial control systems
- 2022
-
Ingår i: 25th Conference on Innovation in Clouds, Internet and Networks (ICIN). - 9781728186887
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Konferensbidrag (refereegranskat)abstract
- In recent years, because the cloud can provide huge advantages regarding storage and computing resources, industry has been motivated to move industrial control systems to the cloud. However, the cloud also introduces major security challenges, since moving control systems to the cloud can enable attackers to infiltrate the system and establish an attack that can lead to damages and disruptions with potentially catastrophic consequences. Therefore, intrusion detection and mitigation mechanisms are crucial for cloud-based industrial control systems. In this paper, we propose a method for detection and mitigation of deception attacks on actuator signals in cloud-based industrial control systems. We validate our solution on a real testbed and evaluate its capability by subjecting it to a set of attacks. Our proposed solution can detect the attack in a timely manner and keep the plant stable, with an acceptable performance during the attack.
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| 6. |
- Akbarian, Fatemeh, et al.
(författare)
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Resilient Cloud Control System: Dynamic Frequency Adaptation via Q-learning
- 2024
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Ingår i: 27th Conference on Innovation in Clouds, Internet and Networks (ICIN). - 9798350393774 - 9798350393767
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Konferensbidrag (refereegranskat)abstract
- Traditional control systems face challenges in managing high data loads and computing power, prompting the evolution of Cloud Control Systems (CCS)-a fusion of Networked Control Systems (NCS) and cloud computing. Despite offering manifold advantages, CCS encounters hurdles in navigating the dynamic cloud environment characterized by fluctuating workloads, rendering static frequency settings inefficient. Moreover, the optimal utilization of cloud resources poses a pivotal challenge within CCS operations. To address these, the paper proposes a resilient CCS by adapting system frequency dynamically. Leveraging Q-learning, the approach measures Round Trip Time (RTT) and system output errors, dynamically adjusting the system's frequency to minimize control costs, optimize performance within the dynamic cloud environment, and achieve resource frugality, minimizing resource usage. Through real testbed experiments, this paper evaluates and analyzes the effectiveness of the proposed method, aiming to establish an adaptive and efficient control framework aligned with evolving cloud dynamics.
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| 7. |
- Callebaut, Gilles, et al.
(författare)
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An Open Dataset Storage Standard for 6G Testbeds
- 2023
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Ingår i: 2023 IEEE Conference on Antenna Measurements and Applications (CAMA). - 9798350323047 ; , s. 347-352
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Konferensbidrag (refereegranskat)abstract
- The emergence of sixth-generation (6G) networks has spurred the development of novel testbeds, including sub-THz networks, cell-free systems, and 6G simulators. To maximize the benefits of these systems, it is crucial to make the generated data publicly available and easily reusable by others. Although data sharing has become a common practice, a lack of standardization hinders data accessibility and interoperability. In this study, we propose the Dataset Storage Standard (DSS) to address these challenges by facilitating data exchange and enabling convenient processing script creation in a testbed-agnostic manner. DSS supports both experimental and simulated data, allowing researchers to employ the same processing scripts and tools across different datasets. Unlike existing standardization efforts such as SigMF and NI RF Data Recording API, DSS provides a broader scope by accommodating a common definition file for testbeds and is not limited to RF data storage. The dataset format utilizes a hierarchical structure, with a tensor representation for specific experiment scenarios. In summary, DSS offers a comprehensive and flexible framework for enhancing the FAIR principles (Findability, Accessibility, Interoperability, and Reusability) in 6G testbeds, promoting open and efficient data sharing in the research community.
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| 8. |
- Callebaut, Gilles, et al.
(författare)
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Dynamic Federations for 6G Cell-Free Networking: Concepts and Terminology
- 2022
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Ingår i: 23rd International Workshop on Signal Processing Advances in Wireless Communication (SPAWC). - 9781665494564 - 9781665494557
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Konferensbidrag (refereegranskat)abstract
- Cell-Free networking is one of the prime candidatesfor 6G networks. Despite being capable of providing the 6Gneeds, practical limitations and considerations are often neglectedin current research. In this work, we introduce the conceptof federations to dynamically scale and select the best set ofresources, e.g., antennas, computing and data resources, to servea given application. Next to communication, 6G systems are expected to provide also wireless powering, positioning and sensing,further increasing the complexity of such systems. Therefore,each federation is self-managing and is distributed over thearea in a cell-free manner. Next to the dynamic federations,new accompanying terminology is proposed to design cell-freesystems taking into account practical limitations such as timesynchronization and distributed processing. We conclude withan illustration with four federations, serving distinct applications,and introduce two new testbeds to study these architectures andconcepts.
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| 9. |
- Chamideh, Seyedezahra, et al.
(författare)
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A Safe and Robust Autonomous Intersection Management System Using a Hierarchical Control Strategy and V2I Communication
- 2023
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Ingår i: IEEE Systems Journal. - 1937-9234. ; 17:1
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Tidskriftsartikel (refereegranskat)abstract
- Connected autonomous vehicles can significantly improve the safety and mobility of urban transportation systems. However, these systems are vulnerable to model uncertainties, wireless communication impairments, and external disturbances. In this article, we propose a new autonomous intersection management (AIM) system, called hierarchical model predictive control (HMPC). In HMPC, the intersection coordination unit (ICU) in a global centralized layer is responsible for assigning a safe speed to each vehicle while minimizing the system's cost. In the Local decentralized layer, each vehicle is responsible for tracking the reference speed assigned by the ICU, while avoiding collisions. In our method, each vehicle can use its own sensors to monitor its close surroundings, and take its own decisions on its movements, independent on the control decisions sent from the ICU. We investigate the safety, scalability and robustness of HMPC compared with two well-known AIM methods based on centralized and decentralized control strategies. For the evaluation, we use simulation of urban mobility (SUMO). Further, we study the scalability and performance of the algorithms in the presence of communication impairments associated with wireless channels. Our simulation results show that HMPC can safely handle high traffic flow rates. Also, HMPC is robust to uncertainties caused by the wireless communication.
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| 10. |
- Chamideh, Seyedezahra, et al.
(författare)
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Centralized Coordination of Autonomous Vehicles at Intersections
- 2020
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Ingår i: 2020 International Conference on Software, Telecommunications and Computer Networks (SoftCOM). - 9789532900996 - 9781728175386
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Konferensbidrag (refereegranskat)abstract
- Recent advances in autonomous vehicles present new opportunities in Intelligent transportation systems (ITS) to address urban transport challenges. Therefore, urban traffic scenarios, and in particular intersections as a bottleneck of transportation network, has received significant attention. In this paper we investigate intelligent traffic control mechanisms for autonomous vehicles at intersections as a replacement of traditional intersection control. An edge cloud controller is used to deliver services that provide traffic safety and efficiency to vehicles. Two well-cited optimization algorithms for cooperative vehicles are compared with realistic simulations in SUMO. This side by side comparison helps to gain insight into the strengths and limitations of these types of algorithms.
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| 11. |
- Chamideh, Seyedezahra, et al.
(författare)
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Enhancing Traffic Flow and Safety in Mixed Vehicle Fleets: Mitigating the Influence of Non-Cooperative Vehicles on Autonomous Intersection Management Systems
- 2023
-
Ingår i: 2023 International Conference on Software, Telecommunications and Computer Networks (SoftCOM). - 9798350301076
-
Konferensbidrag (refereegranskat)abstract
- With the rapid advancement of autonomous vehicle technology, integrating mixed autonomous and non-autonomous vehicles that are not cooperative in vehicular network has become a significant challenge. This paper presents an innovative Autonomous Intersection Management (AIM) system designed to optimize traffic flow and enhance intersection safety in such mixed traffic scenarios. By utilizing vehicle-to-infrastructure (V2I) communication and advanced intersection control algorithms, the AIM system showcases the potential of next-generation vehicular network technologies in revolutionizing intersection management. To evaluate the performance of the AIM system and the impact of non-cooperative vehicles, extensive simulations were conducted using realistic traffic scenarios and a mixed traffic model. The results demonstrate that the proposed system effectively enhances intersection throughput, and ensures safe and efficient operations, particularly in situations involving a high proportion of autonomous vehicles. Additionally, the system’s robustness is demonstrated by evaluating its performance under various traffic flow rates and considering imperfect wireless communication conditions.
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| 12. |
- Chamideh, Seyedezahra, et al.
(författare)
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Evaluation of Decentralized Algorithms for Coordination of Autonomous Vehicles at Intersections
- 2021
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Ingår i: 2021 IEEE International Intelligent Transportation Systems Conference (ITSC). - 9781728191423
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Konferensbidrag (refereegranskat)abstract
- Connected Autonomous Vehicles (AVs) with Vehicle-to-Vehicle (V2V) communication are becoming an essential component of the transportation system. Self-driving cars have the potential to optimize the roads' traffic flow, fuel consumption and remove the possibility of human error and distractions. In these systems, all involved vehicles must be fully autonomous for maximum gain. However, a fully automated system requires major updates in the transportation and network infrastructure. In this paper, we investigate intelligent traffic control mechanisms for autonomous vehicles at intersections as a replacement of traditional intersection control (i.e traffic lights). Two well-cited decentralized optimization algorithms for cooperative vehicles are compared with realistic simulations in SUMO. We investigate the safety and feasibility of deploying the proposed algorithms in the real world. Further, we study the scalability and performance of the algorithms in the presence of communication impairments associated with wireless channels. This side-by-side comparison helps to gain insight into the strengths and limitations of these types of algorithms.
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| 13. |
- Chamideh, Seyedezahra, et al.
(författare)
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Impact of Positioning Uncertainty on Autonomous Intersection Management System
- 2024
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Ingår i: 2023 IEEE International Intelligent Transportation Systems Conference (ITSC). ; , s. 1912-1919
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Konferensbidrag (refereegranskat)abstract
- Connected Autonomous Vehicles (AVs) have the potential to revolutionize Intelligent Transportation Systems (ITS) by addressing urban transport challenges, such asAutonomous Intersection Management (AIM). However, the assumption of highly accurate positioning in most ITS applications does not align with real-life situations. While extensive research has been conducted to improve positioning accuracy, few studies have evaluated the impact of position accuracy on AV systems. This paper investigates the level of positioningerrors that our state-of-the-art AIM system, which outperforms conventional intersection management systems, can tolerate. A comprehensive analysis of positioning accuracy requirements for a collision-free AIM system is conducted. The investigationreveals that our AIM system can safely handle vehicles’ movements in the presence of positioning errors up to four meters in a high traffic flow rate. Furthermore, the impact of sensor accuracy and wireless communication uncertainties on control strategies is considered. This research provides valuable insights into the challenges of designing robust autonomous systems that can withstand various uncertainties, including positioning techniques, and demonstrates the potential of AVs in enhancing ITS.
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| 14. |
- Chamideh, Seyedezahra, et al.
(författare)
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Scalable Intelligent Traffic Balancing: Advancing Efficiency, Safety, and Sustainability in Urban Transportation Through Machine Learning and AIM Integration
- 2024
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Ingår i: 2023 IEEE Global Conference on Artificial Intelligence and Internet of Things (GCAIoT).
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Konferensbidrag (refereegranskat)abstract
- With the growing demand for efficient, safe and sustainable transportation systems, the imperative to design intelligent routing and traffic management solutions within urban settings, requiring minimal data exchange and ensuring scalability, becomes evident. This paper introduces an innovative paradigm for traffic management. By seamlessly integrating machine learning and Autonomous Intersection Management (AIM), we propose a highly scalable routing and traffic balancing system. Our innovation significantly reduces data exchange requirements while optimizing traffic flow. By leveraging the power of machine learning algorithms, our proposed system aims to elevate the efficiency, safety, and sustainability of urban transportation networks. This paper provides an insightful overview of our AIM method, explores the application of machine learning in routing, and delineates our approach to achieve effective traffic balancing. Through extensive experimental results and evaluations, we demonstrate the efficacy of our proposed system in enhancing traffic flow and alleviating congestion in urban scenarios.
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| 15. |
- Dürango, Jonas, et al.
(författare)
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A control theoretical approach to non-intrusive geo-replication for cloud services
- 2016
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Ingår i: 2016 IEEE 55TH CONFERENCE ON DECISION AND CONTROL (CDC). - : IEEE. - 9781509018376 ; , s. 1649-1656
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Konferensbidrag (refereegranskat)abstract
- Complete data center failures may occur due to disastrous events such as earthquakes or fires. To attain robustness against such failures and reduce the probability of data loss, data must be replicated in another data center sufficiently geographically separated from the original data center. Implementing geo-replication is expensive as every data update operation in the original data center must be replicated in the backup. Running the application and the replication service in parallel is cost effective but creates a trade-off between potential replication consistency and data loss and reduced application performance due to network resource contention. We model this trade-off and provide a control-theoretical solution based on Model Predictive Control to dynamically allocate network bandwidth to accommodate the objectives of both replication and application data streams. We evaluate our control solution through simulations emulating the individual services, their traffic flows, and the shared network resource. The MPC solution is able to maintain a consistent performance over periods of persistent overload, and is quickly able to indiscriminately recover once the system return to a stable state. Additionally, the MPC balances the two objectives of consistency and performance according to the proportions specified in the objective function.
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| 16. |
- Höst, Stefan, et al.
(författare)
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Network Requirements for Latency-Critical Services in a Full Cloud Deployment
- 2016
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Ingår i: SoftCom 2016.
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Konferensbidrag (refereegranskat)abstract
- The end-point of the cloud trend is that all compu- tational and storage resources leave the homes and move to the cloud. We can be rather certain the future eventually looks like this as IT and telecommunications services are commoditised and the end users’ time, interest and skill to acquire and maintain electronics fade away. The network architecture suitable for such scenario will be analysed in terms of latency critical services to establish delay requirements and feasible localisations of the data centers. It is concluded that for cloud gaming as an example of a time-critical service, the maximum delay is limited to 20 ms. In the network architecture this corresponds to locating the data center in the Main CO, i.e. typically in the aggregation part of a metropolitan network.
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| 17. |
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| 18. |
- Krzywda, Jakub, et al.
(författare)
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Telco Clouds: Modelling and Simulation
- 2015
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Ingår i: Proceedings of the 5th International Conference on Cloud Computing and Services Science. - : SciTePress. - 9789897581045 ; , s. 597-609
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Konferensbidrag (refereegranskat)abstract
- In this paper, we propose a telco cloud meta-model that can be used to simulate different infrastructure con- figurations and explore their consequences on the system performance and costs. To achieve this, we analyse current telecommunication and data centre infrastructure paradigms, describe the architecture of the telco cloud and detail the benefits of merging both infrastructures in a unified system. Next, we detail the dynamics of the telco cloud and identify the components that are the most relevant from the perspective of modelling performance and cost. A number of well established simulation technologies exist for most of the telco cloud components, we thus proceed with surveying existing models in an attempt to construct a suitable composite meta-model. Finally, we present a showcase scenario to demonstrate the scope of our telco cloud simulator.
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| 19. |
- Larsson, Lars, 1983-, et al.
(författare)
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Adaptive and Application-agnostic Caching in Service Meshes for Resilient Cloud Applications
- 2021
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Ingår i: Proceedings of the 2021 IEEE Conference on Network Softwarization (NetSoft) : Accelerating Network Softwarization in the Cognitive Age - Accelerating Network Softwarization in the Cognitive Age. - : IEEE. - 9781665405225 ; , s. 176-180
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Konferensbidrag (refereegranskat)abstract
- Service meshes factor out code dealing with inter-micro-service communication. The overall resilience of a cloud application is improved if constituent micro-services return stale data, instead of no data at all. This paper proposes and implements application agnostic caching for micro services. While caching is widely employed for serving web service traffic, its usage in inter-micro-service communication is lacking. Micro-services responses are highly dynamic, which requires carefully choosing adaptive time-to-life caching algorithms. Our approach is application agnostic, is cloud native, and supports gRPC. We evaluate our approach and implementation using the micro-service benchmark by Google Cloud called Hipster Shop. Our approach results in caching of about 80% of requests. Results show the feasibility and efficiency of our approach, which encourages implementing caching in service meshes. Additionally, we make the code, experiments, and data publicly available.
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| 20. |
- Larsson, Lars, 1983-, et al.
(författare)
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Impact of etcd deployment on Kubernetes, Istio, and application performance
- 2020
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Ingår i: Software, practice & experience. - : John Wiley & Sons. - 0038-0644 .- 1097-024X. ; 50:10, s. 1986-2007
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Tidskriftsartikel (refereegranskat)abstract
- This experience article describes lessons learned as we conducted experiments in a Kubernetes-based environment, the most notable of which was that the performance of both the Kubernetes control plane and the deployed application depends strongly and in unexpected ways on the performance of the etcd database. The article contains (a) detailed descriptions of how networking with and without Istio works in Kubernetes, based on the Flannel Container Networking Interface (CNI) provider in VXLAN mode with IP Virtual Server (IPVS)-backed Kubernetes Services, (b) a comprehensive discussion about how to conduct load and performance testing using a closed-loop workload generator, and (c) an open source experiment framework useful for executing experiments in a shared cloud environment and exploring the resulting data. It also shows that statistical analysis may reveal the data resulting from such experiments to be misleading even when careful preparations are made, and that nondeterministic behavior stemming from etcd can affect both the platform as a whole and the deployed application. Finally, it is demonstrated that using high-performance backing storage for etcd can reduce the occurrence of such nondeterministic behaviors by a statistically significant (P < .05) margin. The implication of this experience article is that systems researchers studying the performance of applications deployed on Kubernetes cannot simply consider their specific application to be under test. Instead, the particularities of the underlying Kubernetes and cloud platform must be taken into account, in particular because their performance can impact that of etcd.
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| 21. |
- Larsson, Lars, 1983-, et al.
(författare)
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Quality-Elasticity: Improved Resource Utilization, Throughput, and Response Times Via Adjusting Output Quality to Current Operating Conditions
- 2019
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Ingår i: IEEE International Conference on Autonomic Computing (ICAC). - : IEEE. - 9781728124124 - 9781728124117
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Konferensbidrag (refereegranskat)abstract
- This work addresses two related problems for on-line services, namely poor resource utilization during regular operating conditions, and low throughput, long response times, or poor performance under periods of high system load. To address these problems, we introduce our notion of quality-elasticity as a manner of dynamically adapting response qualities from software services along a fine-grained spectrum. When resources are abundant, response quality can be increased, and when resources are scarce, responses are delivered at a lower quality to prioritize throughput and response times. We present an example of how a complex online shopping site can be made quality-elastic. Experiments show that, compared to state of the art, improvements in throughput (57% more served queries), lowered response times (8 time reduction for 95th percentile responses), and an estimated 40% profitability increase can be made using our quality-elastic approach. When resources are abundant, our approach may achieve upwards of twice as high resource utilization as prior work in this field.
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| 22. |
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| 23. |
- Larsson, Lars, et al.
(författare)
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Towards Soft Circuit Breaking in Service Meshes via Application-agnostic Caching
- 2021
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Service meshes factor out code dealing with inter-micro-service communication, such as circuit breaking. Circuit breaking actuation is currently limited to an "on/off" switch, i.e., a tripped circuit breaker will return an application-level error indicating service unavailability to the calling micro-service. This paper proposes a soft circuit breaker actuator, which returns cached data instead of an error. The overall resilience of a cloud application is improved if constituent micro-services return stale data, instead of no data at all. While caching is widely employed for serving web service traffic, its usage in inter-micro-service communication is lacking. Micro-services responses are highly dynamic, which requires carefully choosing adaptive time-to-life caching algorithms. We evaluate our approach through two experiments. First, we quantify the trade-off between traffic reduction and data staleness using a purpose-build service, thereby identifying algorithm configurations that keep data staleness at about 3% or less while reducing network load by up to 30%. Second, we quantify the network load reduction with the micro-service benchmark by Google Cloud called Hipster Shop. Our approach results in caching of about 80% of requests. Results show the feasibility and efficiency of our approach, which encourages implementing caching as a circuit breaking actuator in service meshes.
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| 24. |
- Li, Zheng, et al.
(författare)
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Using a Predator-Prey Model to Explain Variations of Cloud Spot Price
- 2016
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Ingår i: Proceedings of the 6th International Conference on Cloud Computing and Services Science (CLOSER 2016). ; , s. 1-8
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Konferensbidrag (refereegranskat)abstract
- The spot pricing scheme has been considered to be resource-efficient for providers and cost-effective for consumers in the Cloud market. Nevertheless, unlike the static and straightforward strategies of trading on-demand and reserved Cloud services, the market-driven mechanism for trading spot service would be complicated for both implementation and understanding. The largely invisible market activities and their complex interactions could especially make Cloud consumers hesitate to enter the spot market. To reduce the complexity in understanding the Cloud spot market, we decided to reveal the backend information behind spot price variations. Inspired by the methodology of reverse engineering, we developed a Predator-Prey model that can simulate the interactions between demand and resource based on the visible spot price traces. The simulation results have shown some basic regular patterns of market activities with respect to Amazon’s spot instance type m3.large. Although the findings of this study need further validation by using practical data, our work essentially suggests a promising approach (i.e. using a Predator-Prey model) to investigate spot market activities.
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| 25. |
- Ma, Meiyi, et al.
(författare)
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Data sets, modeling, and decision making in smart cities : A survey
- 2019
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Ingår i: ACM Transactions on Cyber-Physical Systems. - : Association for Computing Machinery (ACM). - 2378-962X .- 2378-9638. ; 4:2
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Forskningsöversikt (refereegranskat)abstract
- Cities are deploying tens of thousands of sensors and actuators and developing a large array of smart services. The smart services use sophisticatedmodels and decision-making policies supported by Cyber Physical Systems and Internet of Things technologies. The increasing number of sensors collects a large amount of city data across multiple domains. The collected data have great potential value, but has not yet been fully exploited. This survey focuses on the domains of transportation, environment, emergency and public safety, energy, and social sensing. This article carefully reviews both the data sets being collected across 14 smart cities and the state-of-the-art work in modeling and decision making methodologies. The article also points out the characteristics, challenges faced today, and those challenges that will be exacerbated in the future. Key data issues addressed include heterogeneity, interdisciplinary, integrity, completeness, real-timeliness, and interdependencies. Key decision making issues include safety and service conflicts, security, uncertainty, humans in the loop, and privacy.
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