Usability Requirements for Complex Cyber-Physical Systems in a Totally Networked World

Cyber-physical systems (CPSs) are engineered solutions obtained through the seamless integration of computational algorithms and physical components. Nowadays, they are entitled to drive innovation and competition in different fields such as agriculture, building design and automation, energy, healthcare, transportation and, above all, industrial manufacturing. In fact, CPS technology is going to transform the way people interact with engineered systems — just as the Internet has transformed the way people interact with information. Among CPS technologies, measurement and networking ones play a fundamental role, being enrolled as the natural bridge between the cyber and physical components of a CPS. A number of interconnected sensors and transducers are claimed to give inner and outer, local measurement data that, once processed through suitable algorithms and analytics, have to provide reliable information about the effectiveness of the whole CPS and its interaction with the external world, as well as its health status for maintenance and troubleshooting purposes. So, great attention has to be paid to network models and architectures, to sensor forms and functions, in order to make CPSs properly integrate the continuous and the discrete, compounded by the uncertainty of open environments. The paper aims at opening a preliminary discussion on the role and features of measurement and networking technologies in CPS application fields, with special regard to industrial manufacturing, within a scientific community traditionally close to instrumentation and measurement (IM) issues, in order to stimulate and encourage useful and fruitful cross-fertilization. After some details concerning the general structure of a CPS, its typical architectural model and main features, a special focus is put on CPSs involved in industrial manufacturing along with measurement and networking facets. Some considerations about major measurement challenges that the CPS self-awareness feature poses in maintenance and troubleshooting operations are then drawn. Concluding remarks are finally reported.

Security and Privacy Aspect of Cyber Physical Systems

Cyberphysical system is the integration of physical space (equipment, devices and people) with computing, communication and control systems (cyberspace). The National Institute of Standards and Terminology (NIST) has defined CFS as cyberphysical systems (CFS), which are designed systems built on the continuous integration of computational algorithms and physical components. Improving the CFS provides greater opportunities for performance, adaptability, scalability, stability, security and usability, far exceeding today's simple embedded systems. CFS technology will transform the interaction of people with the engineering system [1, 2]. Today, cyberphysical systems exist in various fields, such as automotive, aerospace, civil, railway, medical. Large productions seek to increase the availability of the asset, while reducing maintenance costs through cyberphysical systems. With the development of the industry and the use of systems in production, the proposed maintenance is used constantly to avoid failures. CFS maintenance is performed when certain indicators signal that the condition of the system has deteriorated. One way to solve this problem is to provide systems with resistance properties. Such systems are able to recover quickly and continue to function in changing conditions [3-9]. Therefore, the urgent task is to develop approaches that will predict the resilience of cyberphysical systems based on cloud computing. It is necessary to build methods and tools that will monitor the condition of the CFS and predict the timely replacement of their components that may fail. The application of the process of predicting the resilience of cyberphysical systems using cloud-oriented increases the effective reliability and availability of cyberphysical systems in its life cycle by identifying future failures and reducing unscheduled maintenance. The forecasting process involves the assessment of the useful life, and the implementation of a post-forecast decision on maintenance measures in accordance with the rules. The method of predicting the resilience of cloud-oriented cyberphysical systems allows to determine the state of the cyberphysical systems using cloud computing. The mechanism used to reduce the cost of maintenance and detailed planning of maintenance operations, the apparatus of genetic algorithms.

Research Purpose: Cyber-Physical Systems solve complex problems through their tight integration between the physical and computational components. Therefore, the reliability of a complex system is the most critical requirement for the cyber-physical system because an unreliable system often leads to service disruption, property damage, financial loses and sometimes lead to fatality. In order to develop more reliable CPS, this paper proposes a generic framework for reliability modeling and analysis for our ongoing work on cyber-physical systems. Research Method: This paper, at first defines an architecture for general CPS which is comprised of three layers; environment layer, communication layer, and computational layer. Secondly, we formalize a reliability model for the architectural components, and then propose a framework for the reliability of CPS with the consideration of how to capture the reliability. Results: Based on the research method, we demonstrate the proposed framework with an illustrative example by using different reliability values from "offshore and onshore reliability data" library. We confirmed that the reliability model covers almost all possible reliabilities required to general cyber-physical systems.

This paper presents definitions characterizing the concepts regarding cyber-physical systems and dependability. Cyber-physical systems incorporate computing, communication and storage capabilities with monitoring and/or control of entities in the physical world in a dependably, securely, efficiently and real-time way. The challenges of cyber-physical system research are concerning: real-time system abstractions; robustness, safety and security; QoS composition; and nor least dependability. Dependability is first introduced as a global concept that subsumes the usual attributes of reliability, availability, safety, integrity and maintainability. The paper aims to define research challenges to achieve the dependability in cyber-physical hydropower systems. The significant challenge of the dependability in cyber-physical hydropower systems is evaluation of the system behavior in terms of interdependencies between cyber and physical components of the system.

The current energy transition combined with the modernization of power systems has provided meaningful transformations in the transmission, distribution, operation, planning, monitoring, and control of power systems. These advancements are heavily dependent on the employment of new computing and communications technologies, which, combined with traditional physical systems, lead to the emergence of cyber–physical systems (CPSs). In this sense, besides the traditional challenges of keeping a reliable, affordable, and safe power grid, one must now deal with the new vulnerabilities to cyberattacks that emerge with the advancement of CPSs. Aware of this perspective and the severity of the ongoing challenges faced by the industry due to cyberattacks, this paper aims to provide a comprehensive survey of the literature on cybersecurity in cyber–physical power systems. For this, clear definitions, historical timelines, and classifications of the main types of cyberattacks, including the concepts, architectures, and basic components that make up, as well as the vulnerabilities in managing, controlling, and protecting, a CPS are presented. Furthermore, this paper presents defense strategies and future trends for cybersecurity. To conduct this study, a careful search was made in relevant academic and industrial databases, leading to a detailed reporting of key works focused on mitigating cyberattacks and ensuring the cybersecurity of modern CPSs. Finally, the paper presents some standards and regulations that technical and international institutions on cybersecurity in smart grids have created.

Context: Cyber-physical systems (CPS) seamlessly integrate computational and physical components. Adaptability, realized through feedback loops, is a key requirement to deal with uncertain operating conditions in CPS. Objective: We aim at assessing state-of-art approaches to handle self-adaptation in CPS at the architectural level. Method: We conducted a systematic literature review by searching four major scientific data bases, resulting in 1103 candidate studies and eventually retaining 42 primary studies included for data collection after applying inclusion and exclusion criteria. Results: The primary concerns of adaptation in CPS are performance, flexibility, and reliability. 64% of the studies apply adap- tation at the application layer and 24% at the middleware layer. MAPE (Monitor-Analyze-Plan-Execute) is the dominant adaptation mechanism (60%), followed by agents and self-organization (both 29%). Remarkably, 36% of the studies combine differ- ent mechanisms to realize adaptation; 17% combine MAPE with agents. The dominating application domain is energy (24%). Conclusions: Our findings show that adaptation in CPS is a cross-layer concern, where solutions combine different adaptation mechanisms within and across layers. This raises challenges for future research both in the field of CPS and self-adaptation, including: how to map concerns to layers and adaptation mechanisms, how to coordinate adaptation mechanisms within and across layers, and how to ensure system-wide consistency of adaptation.

Naval forces rely heavily on Cyber-Physical Systems (CPS) to conduct operations and achieve mission success. As CPS infrastructure becomes exposed to the contested world through networks, CPS security becomes much more important. In a CPS, the cyber components manage the physical components. ONR proposes that the overall goal for CPS resiliency is to have the physical systems behave properly regardless of fault and disruption. Our approach to CPS resiliency focuses on the physical components. We observed that the inertia of the physical components provides a natural but limited resilience, and is capable of tolerating short-term disruption without affecting the health and safety of the CPS. This and the fact that a CPS has a large difference between physical and cyber time scales, enables a unique approach to CPS resiliency. We present Byzantine Fault Tolerant++ (BFT++), a cyber resilient architecture that engineers the cyber components to be brittle against attack, which consequently forces cyber attacks and related disruptions to be short-lived and within tolerance of the physical system’s inertia.

Cyber-Physical Systems (CPS) involve communication, computation, sensing, and actuating through heterogeneous and widely distributed physical devices and computational components. The close interactions of these systems with the physical world places events as the major building blocks for the realization of CPS. More specifically, the system components and design principles should be revisited with a strictly event-based approach. In this paper, a concept lattice-based event model for CPS is introduced. Under this model, a CPS event is uniformly represented by three components: event type, its internal attributes, and its external attributes. The internal and external attributes together characterize the type, spatiotemporal properties of the event as well as the components that observe it. A set of event composition rules are defined where the CPS event composition is based on a CPS concept lattice. The resulting event model can be used both as an offline analysis tool as well as a run-time implementation model due to its distributed nature. A real-life smart home example is used to illustrate the proposed event model. To this end, a CPS event simulator is implemented to evaluate the developed event model and compare with the existing Java implementation of the smart home application. The comparison result shows that the event model provides several advantages in terms of flexibility, QoS support, and complexity. The proposed event model lay the foundations of event-based system design in CPS.

Cyber Physical Systems (CPS), widely used in pervasive computing, integrate computation in the cyber world with control of physical processes. Developing CPS is challenging because interactions between physical and cyber components are complex and often unpredictable. Traditional debugging techniques can detect bugs in the cyber world, but bugs introduced from physical components and induced by limitations in the software interface to physical hardware are still difficult to detect. My research will capture the state of art and the state of the practice in verification and validation of CPS. Based on this, I will design middleware that combines models of the physical world with programming-language based assertions to help developers to design, develop, and debug robust CPS applications with ease.

Cyber-physical systems (CPSs) growth is a fundamental milestone in advancing operations in many industries, including construction. The CPSs technology is mainly divided into three main layers: the physical layer, the network layer, and the information layer. The physical layer is composed of many embedded hardware and systems, taking charge of the gathering and transmission of information and the implementation of control signals, as it is the foundation of the CPSs. The network layer is responsible for the transmission of information and plays an important role in connecting the physical layer and the information layer, so it is regarded as an independent layer. The information layer is responsible for the processing of information. The integration of virtual models and physical construction has been investigated using different data acquisition technologies such as BIM, laser scanners, GPS, and RFID tags for monitoring progress, safety, and other aspects of construction operations. Despite the benefits of applying CPSs in the construction industry, a lot of requirements and challenges faced the implementation of CPSs in construction which should also be taken into consideration. Also, the cost is always a key consideration when deciding to apply new technologies to different scales of a construction project.

Reliability assessment of a power system with cyber-physical interactive operation of photovoltaic systems

Cyber-Physical Systems (CPS) integrates computing and physical processing: their behaviour is dictated by both computation and physical components. In this paper, we present a Model Checking approach for the automatic verification of the correctness of the system at hand. The strengths of our approach are the followings. First, we have implemented the CPS using the modelling and simulation based software JModelica to exploit its modular and parametrizables components. Second, we have verified the system's properties with a model-checking technique to exploit the automaticity of this approach and the completeness of the exploration of all the states of the CPS. In fact, with very few basic notions of the field to investigate, it is possible to design a complete model of a CPS. The system we model, for our proof of concept, is a Distributed Maximum Power Point Tracking (DMPPT) for photovoltaic systems, which relies on a control software to manage the system in every condition imposed by the environment (e.g. irradiation, temperature). We have parameterized the main physical inputs to carry out an automatic verification of a thorough simulation of the circuit under a large number of operational conditions, to deeply investigate the critical aspects of the system. The final goal of our study has been to design a tool to enable automatic verification using a model-checking approach in order to ensure the system correctness with respect to given requirements provided by the designer.

Cyber-Physical Systems (CPSs) are systems which integrate computational, networking, and physical components within a single functional environment. They play an important role in critical infrastructure, government, and everyday life. CPSs encumber many requirements, such as robustness, safety and security, Quality of Service (QoS), and trust. In addition, CPSs combine a variety of digital and analog technologies. Consequently, their analysis, verification, and control can be challenging. The science of protecting CPSs from blended attacks, those combining cyber and physical attack vectors, is yet to be developed. A much-needed tool on this front is a suitable test environment in which to pursue lines of experimentation and exploration. This chapter describes a testbed that allows researchers to experiment on blended attack and defense scenarios in CPSs through gamification. The testbed features many different systems, both cyber and physical, that are fully instrumented for data analysis and assessment.

Cyber-Physical System (CPS) is a symbol of the fourth industrial revolution (4IR) by integrating physical and computational processes which can associate with humans in various ways. In short, the relationship between Cyber networks and the physical component is known as CPS, which is assisting to incorporate the world and influencing our ordinary life significantly. In terms of practical utilization of CPS interacting abundant difficulties. Currently, CPS is involved in modern society very vastly with many uptrend perspectives. All the new technologies by using CPS are accelerating our journey of innovation. In this paper, we have explained the research areas of 14 important domains of Cyber-Physical Systems (CPS) including aircraft transportation systems, battlefield surveillance, chemical production, energy, agriculture (food supply), healthcare, education, industrial automation, manufacturing, mobile devices, robotics, transportation, and vehicular. We also demonstrated the challenges and future direction of each paper of all domains. Almost all articles have limitations on security, data privacy, and safety. Several projects and new dimensions are mentioned where CPS is the key integration. Consequently, the researchers and academicians will be benefited to update the CPS workspace and it will help them with more research on a specific topic of CPS. 158 papers are studied in this survey as well as among these, 98 papers are directly studied with the 14 domains with challenges and future instruction which is the first survey paper as per the knowledge of authors.