Effect of fuzzy PID controller on feedback control systems based on wireless sensor network

Wireless Networked control system (WNCS) has an important in all aspects of the life and in the research fields of Engineering. In this article, a real-time implementation of the wireless feedback control system (WFCS) is performed. The stability issue in the closed-loop control system still suffer from noise, disturbances, and need careful considerations to handle it. Three cases to discover the ability of a Fuzzy PID controller to maintain better angular position control system (PCS) is addressed and controlled by a personal computer through a wireless sensor network(WSN) constructed by ZigBee platforms. The practical issues related with the design and implementation of the wireless computerized control system (WCCS) is discussed and analyzed. The simulation results carried out with Matlab/Simulink 2018b. Different parameters effect such as maximum overshoot, sampling frequency, distance and delay time have been studied. These effects on overall system performance would be discussed. Improving the efficient use of ZigBee platform for WFCS. The simulation and experimental results prove the proposed algorithm in the field of wireless control system

Security of Cyber-Physical Systems in the Presence of Transient Sensor Faults

This paper is concerned with the security of modern Cyber-Physical Systems in the presence of transient sensor faults. We consider a system with multiple sensors measuring the same physical variable, where each sensor provides an interval with all possible values of the true state. We note that some sensors might output faulty readings and others may be controlled by a malicious attacker. Different from previous works, in this paper we aim to distinguish between faults and attacks and develop an attack detection algorithm for the latter only. To do this, we note that there are two kinds of faults – transient and permanent; the former are benign and short-lived whereas the latter may have dangerous consequences on system performance.We argue that sensors have an underlying transient fault model that quantifies the amount of time in which transient faults can occur. In addition, we provide a framework for developing such a model if it is not provided by manufacturers. Attacks can manifest as either transient or permanent faults depending on the attacker’s goal. We provide different techniques for handling each kind. For the former, we analyze the worst-case performance of sensor fusion over time given each sensor’s transient fault model and develop a filtered fusion interval that is guaranteed to contain the true value and is bounded in size. To deal with attacks that do not comply with sensors’ transient fault models, we propose a sound attack detection algorithm based on pairwise inconsistencies between sensor measurements. Finally, we provide a real-data case study on an unmanned ground vehicle to evaluate the various aspects of this paper

Cyber-Attacks and the Use of Force: Back to the Future of Article 2(4)

Cyber-attacks – efforts to alter, disrupt, or destroy computer systems, networks, or the information or programs on them – pose difficult interpretive issues with respect to the U.N. Charter, including when, if ever, such activities constitute prohibited “force” or an “armed attack” justifying military force in self-defense. In exploring these issues, and by drawing on lessons from Cold War legal debates about the U.N. Charter, this Article makes two overarching arguments. First, strategy is a major driver of legal evolution. Whereas most scholarship and commentary on cyber-attacks has focused on how international law might be interpreted or amended to take account of new technologies and threats, this Article focuses on the dynamic interplay of law and strategy – strategy generates reappraisal and revision of law, while law itself shapes strategy – and the moves and countermoves among actors with varying interests, capabilities, and vulnerabilities. Second, this Article argues that it will be difficult to achieve international agreement on legal interpretation and to enforce it with respect to cyber-attacks. The current trajectory of U.S. interpretation – which emphasizes the effects of cyber-attacks in analyzing whether they cross the U.N. Charter’s legal thresholds – is a reasonable effort to overcome translation problems of a Charter built for a different era of conflict. However, certain features of cyber-activities make international legal regulation very difficult, and major actors have divergent strategic interests that will pull their preferred doctrinal interpretations and aspirations in different directions, impeding formation of a stable international consensus. The prescription is not to abandon interpretive or multilateral legal efforts to regulate cyber-attacks, but to recognize the likely limits of these efforts and to consider the implications of legal proposals or negotiations in the context of broader security strategy