Automatic instantiation of abstract tests on specific configurations for large critical control systems

Computer-based control systems have grown in size, complexity, distribution and criticality. In this paper a methodology is presented to perform an abstract testing of such large control systems in an efficient way: an abstract test is specified directly from system functional requirements and has to be instantiated in more test runs to cover a specific configuration, comprising any number of control entities (sensors, actuators and logic processes). Such a process is usually performed by hand for each installation of the control system, requiring a considerable time effort and being an error prone verification activity. To automate a safe passage from abstract tests, related to the so called generic software application, to any specific installation, an algorithm is provided, starting from a reference architecture and a state-based behavioural model of the control software. The presented approach has been applied to a railway interlocking system, demonstrating its feasibility and effectiveness in several years of testing experience

A review of key planning and scheduling in the rail industry in Europe and UK

Planning and scheduling activities within the rail industry have benefited from developments in computer-based simulation and modelling techniques over the last 25 years. Increasingly, the use of computational intelligence in such tasks is featuring more heavily in research publications. This paper examines a number of common rail-based planning and scheduling activities and how they benefit from five broad technology approaches. Summary tables of papers are provided relating to rail planning and scheduling activities and to the use of expert and decision systems in the rail industry.EPSR

A dependable automated people mover system modeled and verified using timed automata : a case study

Automated People Movers (APM) are systems for passenger transport with fully automated operation and high frequency service. For this study we have used the system named Aeromovel installed in Porto Alegre, Brazil. Aeromovel is a non-conventional Automatic People Mover whose operation principle is based on pneumatics. This paper proposes the use, in a complementary way, of two analysis techniques, simulation and formal verification, in order to guarantee the desired behavior for an APM propulsion system composed by a centrifugal fan and ten (on-off and proportional) pneumatic valves driven by pneumatic pistons. This approach is based on the use of timed automata and UPPAAL modelchecker. The more focused aspect is the modeling of the propulsion system associated at the distributed control system. Some simulation and formal verification results are presented, considering desired behavior properties in order to improve the system’s dependability

Modeling and simulating the controller behavior of an automated people mover using IEC 61850 communication requirements

Automated People Movers (APM) are systems for passenger transport with fully automated operation and high frequency service. Trains controllers are traditionally centralized and based on wired circuits, although they generally have serious difficulties in the installation and maintenance. As there is increased demand on the system, there are advantages in choosing an open architecture, with a simple communication system and distributed. These concepts are largely addressed in the development of IEC 61850. In this study we proposed the adaptation of the standard IEC 61850, design to be used in electric power systems to be applied in an APM system named Aeromovel installed in Porto Alegre, Brazil. Aeromovel is a nonconventional Automatic People Mover whose operation principle is based on pneumatics. A model, based on timed automata formalism, is proposed for IEC 61850 communications requirements and respective simulation results are presented.Guilherme Kunz is supported by the PTI C&T program (Fundacao Parque Tecnologico Itaipu - FPTI-BR). The authors would like to thank to PTI C&T/FPTI-BR for financial support and to CESUP-UFRGS for access to the clusters

Investigation of Frame Alignments for GMM-based Digit-prompted Speaker Verification

Frame alignments can be computed by different methods in GMM-based speaker verification. By incorporating a phonetic Gaussian mixture model (PGMM), we are able to compare the performance using alignments extracted from the deep neural networks (DNN) and the conventional hidden Markov model (HMM) in digit-prompted speaker verification. Based on the different characteristics of these two alignments, we present a novel content verification method to improve the system security without much computational overhead. Our experiments on the RSR2015 Part-3 digit-prompted task show that, the DNN based alignment performs on par with the HMM alignment. The results also demonstrate the effectiveness of the proposed Kullback-Leibler (KL) divergence based scoring to reject speech with incorrect pass-phrases.Comment: accepted by APSIPA ASC 201

ATLANTIDES: Automatic Configuration for Alert Verification in Network Intrusion Detection Systems

We present an architecture designed for alert verification (i.e., to reduce false positives) in network intrusion-detection systems. Our technique is based on a systematic (and automatic) anomaly-based analysis of the system output, which provides useful context information regarding the network services. The false positives raised by the NIDS analyzing the incoming traffic (which can be either signature- or anomaly-based) are reduced by correlating them with the output anomalies. We designed our architecture for TCP-based network services which have a client/server architecture (such as HTTP). Benchmarks show a substantial reduction of false positives between 50% and 100%

Component-based modeling and observer-based verification for railway safety-critical applications

1th International Symposium on Formal Aspects of Component Software , Bertinoro, Italie, 10-/09/2014 - 12/09/2015International audienceOne of the challenges that engineers face, during the development process of safety-critical systems, is the verification of safety application models before implementation. Formalization is important in order to verify that the design meets the specified safety requirements. In this paper, we formally describe the set of transformation rules, which are defined for the automatic transformation of safety application source models to timed automata target models. The source models are based on our domain-specific component model, named SARA, dedicated to SAfety-critical RAilway control applications. The target models are then used for the observer-based verification of safety requirements. This method provides an intuitive way of expressing system properties without requiring a significant knowledge of higher order logic and theorem proving, as required in most of existing approaches. An experimentation over a chosen benchmark at rail-road crossing protection application is shown to highlight the proposed approach