Incomplete analytic hierarchy process with minimum weighted ordinal violations

Incomplete pairwise comparison matrices offer a natural way of expressing preferences in decision making processes. Although ordinal information is crucial, there is a bias in the literature: cardinal models dominate. Ordinal models usually yield non-unique solutions; therefore, an approach blending ordinal and cardinal information is needed. In this work, we consider two cascading problems: first, we compute ordinal preferences, maximizing an index that combines ordinal and cardinal information; then, we obtain a cardinal ranking by enforcing ordinal constraints. Notably, we provide a sufficient condition (that is likely to be satisfied in practical cases) for the first problem to admit a unique solution and we develop a provably polynomial-time algorithm to compute it. The effectiveness of the proposed method is analyzed and compared with respect to other approaches and criteria at the state of the art.Comment: preprint submitted to the International Journal of General System

A Hardware-in-the-Loop Water Distribution Testbed Dataset for Cyber-Physical Security Testing

This paper presents a dataset to support researchers in the validation process of solutions such as Intrusion Detection Systems (IDS) based on artificial intelligence and machine learning techniques for the detection and categorization of threats in Cyber Physical Systems (CPS). To this end, data were acquired from a hardware-in-the-loop Water Distribution Testbed (WDT) which emulates water flowing between eight tanks via solenoid-valves, pumps, pressure and flow sensors. The testbed is composed of a real subsystem that is virtually connected to a simulated one. The proposed dataset encompasses both physical and network data in order to highlight the consequences of attacks in the physical process as well as in network traffic behaviour. Simulations data are organized in four different acquisitions for a total duration of 2 hours by considering normal scenario and multiple anomalies due to cyber and physical attacks

A Strategy to Improve Infrastructure Survivability via Prioritizing Critical Nodes Protection

From an engineering point of view, the survivability of a system is defined as its ability to continue to operate despite a natural or human-made disturbance; for example a serious mechanical fault, a human error, or a malicious cyber or physical attack. In the context of critical infrastructures, due to their relevance for the public wellness, it is mandatory to improve the robustness of such systems in order to ensure the availability of essential services such as the distribution of water, gas and electrical power. Nowadays, due to the increasing number of cyber incidents, the definition of protection strategies, able to improve the survivability level of this infrastructure, is at the heart of the scientific debate. In this chapter we propose a procedure based on three steps aimed at improving infrastructure survivability. In the first stage we propose some approaches to identify the criticality degree of each subsystem composing the infrastructure, in the second stage we propose a method to aggregate multiple criticality evaluations performed by subject matter experts by providing a unique holistic indicator. Finally, on the basis of such indicator, we propose a protection strategy to improve the robustness of the entire system

Augmenting white cane reliability using smart glove for visually impaired people

The independent mobility problem of visually impaired people has been an active research topic in biomedical engineering: although many smart tools have been proposed, traditional tools (e.g., the white cane) continue to play a prominent role. In this paper a low cost smart glove is presented: the key idea is to minimize the impact in using it by combining the traditional tools with a technological device able to improve the movement performance of the visually impaired people

A low cost smart glove for visually impaired people mobility

Degradation of the visual system reduces the mobility of a person that relies only on his sense of touch and hearing. This paper presents the prototype of a low cost smart glove to improve the mobility of the visually impaired people. The glove is equipped with rangefinders to explore the surroundings: it provides a vibro-tactile feedback on the position of the closest obstacles in range by means of vibration motors. The system is designed to operate with the white cane, enhancing the reliability of this traditional tool

An overview of Cyber Attack to Industrial Control System

The relevance of OT (Operational Technology) in Seveso plats has largely increased in recent years thanks to several benefits related to the improvement of efficiency, quality of the production, and cost reduction. Unfortunately, the use of these technologies exposes the plants to cyber threats. Indeed, a cyber-attack may cause the interruption of the production, and, at worst, could manipulate the control process in order to induce a catastrophic event. In recent years, several cyber-attacks have been performed against Industrial Control Systems. In this paper, we provide a process-engineering oriented overview of those attacks with the aim of illustrating their behavior. Particular attention is payed to Triton attack, being the first worm specifically designed to attack a Safety Instrumented System. The paper concludes with some consideration about a relevant approach that might be useful to increase the protection of the Seveso ICS. Copyright \ua9 2019, AIDIC Servizi S.r.l

Hybrid map building for personal indoor navigation systems

Tracking the positions of people in large indoor spaces is important, since it enables a range of applications related to security, indoor navigation and guidance. This paper proposes a personal indoor navigation system based on hybrid map, containing geometric as well as symbolic information. In this way the same map can be exploited to guide and localise the user efficiently during navigation. The hybrid map is built using floor plans of the environment. It is a topological graph capturing the connectivity of complex indoor environment and it is retrieved by applying image-processing techniques. Some additional metric information are added to make the map suitable for quantitative localisation. Semantic features are considered to improve user readability

Assessing node criticality in dynamical distributed systems

In this paper we characterize the vulnerability of the different elements of a geographically dispersed and networked LTI discrete-time dynamical system by taking the perspective of an attacker aiming at steering the system state towards an undesirable configuration via the injection of control signals at selected subsystems. Specifically, we assume the attacker aims at directly intervening on the minimum number of subsystems and at injecting the minimum energy signal that would steer the state towards the target adverse configuration, while minimizing the number of steps required to reach such a configuration. Such three conflicting objectives generate a Pareto front of solutions, and the vulnerability of each subsystem is evaluated in terms of the frequency with which each node is attacked in the solutions belonging to the Pareto front. Such a vulnerability assessment can be the base to prioritize the protection resources to be allocated at each subsystem