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Visualizing Network Flows and Related Anomalies in Industrial Networks using Chord Diagrams and Whitelisting
Get PDFIndustrial Control Systems are the set of specialized elements that monitor and control physical processes. Those systems are normally interconnected forming environments known as industrial networks. The particularities of these networks disallow the usage of traditional IT security mechanisms, while allowing other security strategies not suitable for IT networks. As industrial network traffic flows follow constant and repetitive patterns, whitelisting has been proved a viable approach for anomaly detection in industrial networks. In this paper, we present a network flow and related alert visualization system based on chord diagrams. The system represents the detected network flows within a time interval, highlighting the ones that do not comply the whitelisting rules. Moreover, it also depicts the network flows that, even if they are registered in the whitelist, have not been detected on the selected time interval (e.g. a host is down). Finally, the visualization system is tested w ith network data coming from a real industrial network
A Data-Driven Health Assessment Method for Electromechanical Actuation Systems
Get PDFThe design of health assessment applications for the electromechanical actuation system of the aircraft is a challenging task. Physics-of-failure models involve non-linear complex equations which are further complicated at the system-level. Data-driven techniques require run-to-failure tests to predict the remaining useful life. However, components are not allowed to run until failure in the aerospace engineering arena. Besides, when adding new monitoring elements for an improved health assessment, the airliner sets constraints due to the increased cost and weight. In this context, the health assessment of the electromechanical actuation system is a challenging task. In this paper we propose a data-driven approach which estimates the health state of the system without runto-failure data and limited health information. The approach combines basic reliability theory with Bayesian concepts and obtained results show the feasibility of the technique for asset health assessment
On the Feasibility of Distinguishing Between Process Disturbances and Intrusions in Process Control Systems using Multivariate Statistical Process Control
Get PDFProcess Control Systems (PCSs) are the operat-ing core of Critical Infrastructures (CIs). As such, anomalydetection has been an active research field to ensure CInormal operation. Previous approaches have leveraged networklevel data for anomaly detection, or have disregarded theexistence of process disturbances, thus opening the possibility of mislabelling disturbances as attacks and vice versa. In thispaper we present an anomaly detection and diagnostic systembased on Multivariate Statistical Process Control (MSPC), thataims to distinguish between attacks and disturbances. For this end, we expand traditional MSPC to monitor process leveland controller level data. We evaluate our approach using the Tennessee-Eastman process. Results show that our approachcan be used to distinguish disturbances from intrusions to acertain extent and we conclude that the proposed approach canbe extended with other sources of data for improving results
Different approaches for the detection of SSH anomalous connections
Get PDFThe Secure Shell Protocol (SSH) is a well-known standard protocol, mainly used for remotely accessing shell accounts on Unix-like operating systems to perform administrative tasks. As a result, the SSH service has been an appealing target for attackers, aiming to guess root passwords performing dictionary attacks or to directly exploit the service itself. To identify such situations, this article addresses the detection of SSH anomalous connections from an intrusion detection perspective. The main idea is to compare several strategies and approaches for a better detection of SSH-based attacks. To test the classification performance of different classifiers and combinations of them, SSH data coming from a real-world honeynet are gathered and analysed. For comparison purposes and to draw conclusions about data collection, both packet-based and flow data are analysed. A wide range of classifiers and ensembles are applied to these data, as well as different validation schemes for better analysis of the obtained results. The high-rate classification results lead to positive conclusions about the identification of malicious SSH connections
Delta Rhapsody
Get PDFModel Based System Engineering (MBSE) has become the pre-eminent paradigm used to improve the development of complex systems. Additionally, Delta Modelling provides an incremental approach to the design and maintenance of models when there is variability in the system. In this context, the market leading IBM Rhapsody® provides a professional and wide range of functionalities. Nevertheless, there is not support for Delta Modelling in IBM Rhapsody®. To meet this need, the Delta Rhapsody solution has been developed. With the tool a new variant model can be automatically generated applying deltas to a core model. The application of the solution in an industrial case study has been undertaken. From this, it was concluded that the Delta Rhapsody solution notably reduces the required time to develop a variant model. To further improve the Delta Rhapsody solution, some future works have also been identified
Tool Damage and Adhesion Effects in Turning and Drilling of Hardened Steels
Get PDFNoteworthy results have been obtained in the turning and drilling of hardened high-strength steels using tungsten carbide based cutting tools. In a finish turning process, it was seen that surface roughness and tool flank wear followed very different trends against cutting time. The suggested explanation for this behaviour is that the profile cut into the workpiece surface is determined by the tool’s cutting edge profile. It is shown that the profile appearing on the cut surface changes rapidly over time, so the profile of the tool cutting edge should also be changing rapidly. Workpiece material adhered onto the cutting tool, which is also known as a built-up edge, is a phenomenon which could explain the observations made. In terms of tool damage modes, workpiece material adhesion is believed to have contributed to tool wear in examples provided from finish turning, thread turning and drilling. Additionally, evidence of tool fracture and tool abrasion were recorded
Vibration attenuation of conductive beams by inducing eddy currents
Get PDFThe increasing requirements for structural vibration control in many industries, require innovative attenuation techniques. In this work, the phenomenon of eddy currents is proposed to reduce the vibration of conductive and non-magnetic beam-like structures without modifying the system, neither the weight nor the stiffness. The motion of a conductive material in a stationary magnetic field induces eddy currents, which in turn generate a repulsive force and attenuate the vibration. In this study, the vibrational response of a thin aluminium beam under a partial and stationary magnetic field is analysed. The influence of the eddy currents is experimentally studied in the bandwidth from 0 to 1 kHz and a preliminary numerical model is proposed. The results show the vibration of all the length of the beam can be attenuated by inducing eddy currents, whereas the natural frequencies of the system remain unmodified. The attenuation of the vibration is more remarkable at low frequencies and when the position of the magnetic field coincides with a maximum vibration of a mode
Roll levelling semi-analytical model for process optimization
Get PDFRoll levelling is a primary manufacturing process used to remove residual stresses and imperfections of metal strips in order to make them suitable for subsequent forming operations. In the last years the importance of this process has been evidenced with the apparition of Ultra High Strength Steels with strength > 900 MPa. The optimal setting of the machine as well as a robust machine design has become critical for the correct processing of these materials. Finite Element Method (FEM) analysis is the widely used technique for both aspects. However, in this case, the FEM simulation times are above the admissible ones in both machine development and process optimization. In the present work, a semi-analytical model based on a discrete bending theory is presented. This model is able to calculate the critical levelling parameters i.e. force, plastification rate, residual stresses in a few seconds. First the semi-analytical model is presented. Next, some experimental industrial cases are analyzed by both the semi-analytical model and the conventional FEM model. Finally, results and computation times of both methods are compared
Modeling approach to managing the deployment of integrated organizational models for multi-morbid patients in the CareWell study. The Basque Country case
Get PDFIntroduction: An integrated care approach supported by information and communication technologies (ICT) is being deployed in the Basque Country within the European CareWell project, to best respond to the complex needs of multi-morbid patients. Our statistical analysis carried out in Donostialdea County has demonstrated that the profile of resource consumption has not shown the expected changes. The fact that no significant differences were found indicates that the aim of maintaining stability in multi-morbid patients has not been achieved. However, this is just a static view of the situation two years after the initial deployment. Although necessary, this information is not enough to assess the efficacy of the intervention since the way in which health care is organized is considered as a unitary actor, either adapting to the environment or remaining inert. Integration of health care requires the alteration of delivery processes that change over time in predictable and unpredictable ways. Some processes may be altered more quickly than others, depending on how long it takes for the health-care staff to achieve the necessary behavioural changes. The objective of this work was to apply predictive modeling adapted to the local context to develop a tool within the Deming’s plan-do-check-act (PDCA) cycle to manage continuous improvement in integrated interventions over the long term in the CareWell project
Analytical model to calculate magnetic flux density in permanent magnet synchronous machines with static eccentricity
Get PDFIn this article a general analytical model for the analysis of permanent magnet synchronous machines with static eccentricity is presented. The model is a continuation of [1] and it is based on Fourier time-space series formulated in 2-D coordinates. The results of the model are corroborated by simulations of finite element method over two different machines. The results of the model show a good agreement with the results obtained from simulations