Cyber-physical System Components Research Articles

An approach for assessing the functional vulnerabilities criticality of CPS components

Timely identification of critical security flaws in a cyber-physical system makes identifying risks and potential threats possible. To address this issue, threat models are created to better understand potential vulnerabilities that must be considered to ensure system reliability. Selecting the optimal solution for assessing the functional vulnerabilities criticality of cyber-physical system components is a complex process since all vulnerabilities must be identified, classified, and quantified according to a unified approach as part of the cybersecurity process. An effective tool for cyber-physical systems analysis is the Bayesian attack graph. Each path in the graph represents a sequence of attacks that an attacker can use to achieve a specific goal, such as gaining access to sensitive data or controlling a system. This paper proposes a quantitative method for assessing the vulnerability criticality of cyber-physical system components based on the Promethee II multi-criteria decision-making method. It allows ranking and identification of the system's most vulnerable components. The proposed approach is evaluated using a threat model and three scenarios of cyberattacks on a cyber-physical system. Comparison with TOPSIS, VIKOR, and ELECTRE methods proves the effectiveness of the proposed approach. The proposed approach can help technical specialists make more reasoned decisions when ranking critical vulnerabilities of cyber-physical system components to provide security measures and prevent cyberattacks.

A REFERENCE ARCHITECTURE OF HUMAN CYBER-PHYSICAL SYSTEMS – PART III: SEMANTIC FOUNDATIONS

The design and analysis of multi-agent human cyber-physical systems in safety-critical or industry-critical domains calls for an adequate semantic foundation capable of exhaustively and rigorously describing all emergent effects in the joint dynamic behavior of the agents that are relevant to their safety and well-behavior. We present such a semantic foundation. This framework extends beyond previous approaches by extending the agent-local dynamic state beyond state components under direct control of the agent and belief about other agents (as previously suggested for understanding cooperative as well as rational behavior) to agent-local evidence and belief about the overall cooperative, competitive, or coopetitive game structure. We argue that this extension is necessary for rigorously analyzing systems of human cyber-physical systems because humans are known to employ cognitive replacement models of system dynamics that are both non-stationary and potentially incongruent. These replacement models induce visible and potentially harmful effects on their joint emergent behavior and the interaction with cyber-physical system components.

A state-of-the-art digital factory integrating digital twin for laser additive and subtractive manufacturing processes

PurposeThis study aims to discuss the state-of-the-art digital factory (DF) development combining digital twins (DTs), sensing devices, laser additive manufacturing (LAM) and subtractive manufacturing (SM) processes. The current shortcomings and outlook of the DF also have been highlighted. A DF is a state-of-the-art manufacturing facility that uses innovative technologies, including automation, artificial intelligence (AI), the Internet of Things, additive manufacturing (AM), SM, hybrid manufacturing (HM), sensors for real-time feedback and control, and a DT, to streamline and improve manufacturing operations.Design/methodology/approachThis study presents a novel perspective on DF development using laser-based AM, SM, sensors and DTs. Recent developments in laser-based AM, SM, sensors and DTs have been compiled. This study has been developed using systematic reviews and meta-analyses (PRISMA) guidelines, discussing literature on the DTs for laser-based AM, particularly laser powder bed fusion and direct energy deposition, in-situ monitoring and control equipment, SM and HM. The principal goal of this study is to highlight the aspects of DF and its development using existing techniques.FindingsA comprehensive literature review finds a substantial lack of complete techniques that incorporate cyber-physical systems, advanced data analytics, AI, standardized interoperability, human–machine cooperation and scalable adaptability. The suggested DF effectively fills this void by integrating cyber-physical system components, including DT, AM, SM and sensors into the manufacturing process. Using sophisticated data analytics and AI algorithms, the DF facilitates real-time data analysis, predictive maintenance, quality control and optimal resource allocation. In addition, the suggested DF ensures interoperability between diverse devices and systems by emphasizing standardized communication protocols and interfaces. The modular and adaptable architecture of the DF enables scalability and adaptation, allowing for rapid reaction to market conditions.Originality/valueBased on the need of DF, this review presents a comprehensive approach to DF development using DTs, sensing devices, LAM and SM processes and provides current progress in this domain.

An Evaluation of Cyber Physical System (CPS) or Intelligent System in Which a Mechanism is Controlled or Monitored by Computer Based Algorithms

This article is based on the CPS or cyber-physical system or intelligent system. The term “physical” is associated with natural and also human man-made systems that have been governed by the laws that are connected with physics while operating in continuity. CPS is described as the network of some embedded systems which establishes an interaction with both physical inputs as well as output. CPS faces the challenges of cyber and physical threats as these systems have been found to be of heterogeneous nature that has a reliance on both private and sensitive data. This study has focused on the CPS and CPS components as well. This is the integration of sensing, controlling, networking and computation into some physical objects as well as infrastructures that connect them through the help of the internet with each other. There are some CPS components that have been utilized for sensing different types of information where the CPS components can be classified into Sensing Components (SC) and also Controlling Components (CC). this study also shed light on the “Programmable Logic Controllers” (PLC) have been created for replacing hard-wired relays and have been assumed in the form of “industrial digital computers” controlling manufacturing processes including the performance of robotic performance. This study has also shed light on the improvements in unsupervised intrusion detection within CPS. Intrusion Detection Systems (IDSs) have been becoming certain building blocks for developing the CPS while detecting its potential threats and also triggering the modules to block and also mitigate those adverse impacts from cyber threats. Development via digital twin through CPS. The CPS paradigm has been involved with physical and software components that have been deeply intertwined with each other where each component has been operating on both spatial and temporal scales possessing multiple behavioural modalities and also interacting with each other. Keywords : CPS systems, intelligent algorithms running, intelligent interfaces, open architecture system CPS, RFID- based position detection.

An enhanced predictive hierarchical power management framework for islanded microgrids

This paper proposes an enhanced three-layer predictive hierarchical power management framework for secure and economic operation of islanded microgrids. The tertiary control, guaranteeing the microgrid economic operation, is built upon the semi-definite programming-based AC optimal power flow model, which periodically sends power references to secondary control. To mitigate uncertainties arising from renewable generations and loads, a centralized linear model predictive control (MPC) controller is proposed and implemented for secondary control. The MPC controller can effectively regulate the microgrid system frequency by closely tracking reference signals from the tertiary controller with low computational complexity. Droop-based primary controllers are implemented to coordinate with the secondary MPC controller to balance the system in real time. Both synchronous generators (SGs) and solar photovoltaics (PVs) are simulated in the microgrid power management framework. A unified linear input-state estimator (ULISE) is proposed for SG state variable estimation and control anomaly detection due to compromised cyber-physical system components, etc. Simulation results demonstrated that SG states can be accurately estimated, while inconsistency in control signals can be effectively detected for an enhanced MPC. Furthermore, comparing with conventional proportional-integral (PI) control, the proposed hierarchical power management scheme exhibits superior frequency regulation capability whilst maintaining lower system operating costs.

An Automated Sensor Fusion Approach for the RUL Prediction of Electromagnetic Pumps

The remaining useful life (RUL) prediction of industrial cyber-physical system components demands the use of reliable prognostics parameters and frameworks. Against the traditional use of a single measure of degradation, data from multiple sensors provide abundant characteristic information for modeling, assessing, and extracting useful parameters via appropriate signal processing and sensor fusion methods. This study introduces a multi-sensor prognostics approach which merges highly prognosible statistical features from vibrational and pressure sensor measurements after a multi-level wavelet decomposition of the signals. The prognostic algorithm presented in this work for solenoid pump RUL prediction is a multi-objective genetic algorithm-optimized long short-term memory (MOGA-LSTM) which accepts the fused sensor features as input and returns the RUL of the pump as output. The framework was tested on a run-to-failure experiment on a VSC63A5 Solenoid pump following a significant pump malfunction caused by a clogged suction filter after the test. Using standard prognostic performance evaluation metrics, the performance of the prognostics framework was compared with other reliable state-of-the-art methods with a remarkable comparative advantage in addition to better automation potentials for real-time condition monitoring and RUL prediction.

Survey on Unmanned Aerial Vehicle Networks: A Cyber Physical System Perspective

Unmanned aerial vehicle (UAV) networks are playing an important role in various areas due to their agility and versatility, which have attracted significant attention from both the academia and industry in recent years. As an integration of the embedded systems with communication devices, computation capabilities and control modules, the UAV network could build a closed loop from data perceiving, information exchanging, decision making to the final execution, which tightly integrates the cyber processes into the physical devices. Therefore, the UAV network could be considered as a cyber physical system (CPS). Revealing the coupling effects among the three interacted components in this CPS system, i.e., communication, computation and control, is envisioned as the key to properly utilize all the available resources and hence improve the performance of the UAV networks. In this paper, we present a comprehensive survey on the UAV networks from a CPS perspective. Firstly, we respectively research the basics and advances with respect to the three CPS components in the UAV networks. Then we look inside to investigate how these components contribute to the system performance by classifying the UAV networks into three hierarchies, i.e., the cell level, the system level, and the system of system level. Further, the coupling effects among these CPS components are explicitly illustrated, which could be enlightening to deal with the challenges in each individual aspect. New research directions and open issues are discussed at the end of this survey. With this intensive literature review, we try to provide a novel insight into the state-of-the-art in the UAV networks.

IoT, IIoT and Cyber-Physical Systems Integration in the SEPT Learning Factory

Abstract The SEPT Learning Factory (LF) is a state-of-the art learning environment for students with a focus on designing, prototyping, manufacturing, and testing processes that incorporate key aspects of IoT, IIoT, and Industry 4.0. The infrastructure to support the operations of various cyber-physical system components in the LF consist of critical elements such as computing and networking components. The prototyping and production system components are integrated with digital technology components. This paper describes the use of these elements in the LF. Several messaging platforms used for implementing IoT and IIoT protocols are available to students for data collection, visualization and analytics. This paper describes the use of these protocols, the implementation and integration of IoT and IIoT stations, cyber-physical system control stations, manufacturing machines and collaborative robots.

Toward Plug&Play Cyber-Physical System Components

The automated interoperability of cyber-physical system components is a feature enabling the construction of more flexible and robust automation solutions. We describe the issues related to integration and propose a Plug&Play solution that allows plugging a self-describing device producing self-described data to a larger system. This solution utilizes OPC Unified Architecture (UA) and Semantic Web technologies to achieve integration at various levels. We illustrate and discuss this approach on our developed Semantic Big Data Historian and experimental cyber-physical system, which was proposed to resolve the hydroelectric power plant “stop-problem.”

Modeling and Verifying of CPS Component Services Based on Hybrid Automata

In recent years, the modeling and verifying of Cyber-Physical System (CPS) is now an important aspect of CPS researches. Because of the CPS’ complex architecture, it may suffer from the state-space explosion problem when we verify CPS models by model checking methods. Therefore, we offer a method which models CPS with Component Services. The method treats the CPS components as a service provider, and models component services to further simplify the system’s state-space. We verify the correctness of this model and solve the synchronous/asynchronous communication problems.

Adaptive network-based fuzzy inference model on CPS for large scale intelligent and cooperative surveillance

This paper proposes Cyber-Physical System (CPS) architectures for Large Scale Intelligent and Cooperative Surveillance (ICS) and presents an Adaptive Network-based Fuzzy Inference Model (ANFIM) for reducing the false accident-event report rates of Controller Manager (CM) systems among CPS components. In ICS, sensor nodes detect traffic accident events from general roads and crossroads and transmit event attribute values (car and accident types), time attribute values (date, month, day, year), environmental variable values (weather, temperature, luminous intensity, humidity and sound), and accident event videos to the Controller through WSN mesh networks. Using these pieces of information, the Controller conducts image processing and delivers all sensing data to the CM together with accident-event probability values. The CM conducts data filtering with multi regression analysis utilizing the past accident event database. Centering on the resultant values obtained through the foregoing process, this paper proposes a mathematical model for influence analysis of environmental variables that affect accident events. Based on the model's results, the authors establish a Sugeno Type fuzzy rule base for reducing false accident-event report rates to propose an ANFIM.

A Novel Reliability Assurance Method for Cyberphysical System Components Substitution

Reliability of cyberphysical system (CPS) components substitution is an important issue for CPS troubleshooting and system upgrading. In this paper, decision problem of components substitution is regarded as decision problem of services substitution through a service-oriented architecture of CPS. Further, a reliability assurance method for CPS service substitution is proposed, which comprises two parts. The first one is a qualitative judgment method for CPS service substitution according to the relationship between service compatibility and substitution based on time-space -calculus with time and space operators. The other one is consisted of substitution processes from above judgment results based on service management theory. Finally, a case study is performed to show how to apply this method to ensure CPS components reliable substitution. The experimental result shows that this method is reasonable and feasible.