A comparative reliability analysis of ETCS train radio communications

StoCharts have been proposed as a UML statechart extension for performance and dependability evaluation, and were applied in the context of train radio reliability assessment to show the principal tractability of realistic cases with this approach. In this paper, we extend on this bare feasibility result in two important directions. First, we sketch the cornerstones of a mechanizable translation of StoCharts to MoDeST. The latter is a process algebra-based formalism supported by the Motor/Möbius tool tandem. Second, we exploit this translation for a detailed analysis of the train radio case study

Developing a distributed electronic health-record store for India

The DIGHT project is addressing the problem of building a scalable and highly available information store for the Electronic Health Records (EHRs) of the over one billion citizens of India

From StoCharts to MoDeST: a comparative reliability analysis of train radio communications

StoCharts have been proposed as a UML statechart extension for performance and dependability evaluation, and have been applied in the context of train radio reliability assessment to show the principal tractability of realistic cases with this approach. In this paper, we extend on this bare feasibility result in two important directions. First, we sketch the cornerstones of a mechanizable translation of StoCharts to MoDeST. The latter is a process algebra-based formalism supported by the Motor/Möbius tool tandem. Second, we exploit this translation for a detailed analysis of the train radio case study

Implications of Cyber Security to Safety Approval in Railway

The railway domain has a justifiable preoccupation with safety, but less of a focus on cyber security. This could result in the risk of cyber security flaws in current railway systems being unacceptably high. However, in recent years the railway industry has realized the importance of cyber security, and the possible effects cyber security could have on safety functions, necessitating these aspects to also be considered as part of the safety approval. This trend can be seen from the fact that later updates of the railway standards from CENELEC to a larger degree include cyber security. This is also a consequence of the increasing digitalisation trend in the railway sector, as elsewhere in society (e.g., the ERTMS national implementation project in Norway). This paper presents findings from a brief literature study on how railway systems are vulnerable to cyber security threats and discusses how cyber security issues are covered by current railway legislation. Challenges related to the handling of cyber security threats as part of the railway approval processes is then elaborated. The fact that cyber security threats change faster than the pure safety threats must be taken into account. The problem is viewed from an independent safety assessor's point of view. Some major findings of the study are elaborated, and conclusions on how to deal with cyber security as part of the railway approval process are outlined with pros and cons.acceptedVersio

Implications of Cyber Security to Safety Approval in Railway

The railway domain has a justifiable preoccupation with safety, but less of a focus on cyber security. This could result in the risk of cyber security flaws in current railway systems being unacceptably high. However, in recent years the railway industry has realized the importance of cyber security, and the possible effects cyber security could have on safety functions, necessitating these aspects to also be considered as part of the safety approval. This trend can be seen from the fact that later updates of the railway standards from CENELEC to a larger degree include cyber security. This is also a consequence of the increasing digitalisation trend in the railway sector, as elsewhere in society (e.g., the ERTMS national implementation project in Norway). This paper presents findings from a brief literature study on how railway systems are vulnerable to cyber security threats and discusses how cyber security issues are covered by current railway legislation. Challenges related to the handling of cyber security threats as part of the railway approval processes is then elaborated. The fact that cyber security threats change faster than the pure safety threats must be taken into account. The problem is viewed from an independent safety assessor's point of view. Some major findings of the study are elaborated, and conclusions on how to deal with cyber security as part of the railway approval process are outlined with pros and cons.acceptedVersio

Biological Terrorism, Emerging Diseases, and National Security

Examines the extent to which bioterrorist attacks have proven or may prove difficult to distinguish from outbreaks of emerging diseases. Makes recommendations for how the U.S. could better prepare to meet the threat of biological terrorism

The uses of process modeling : a framework for understanding modeling formalisms

There is wide-spread recognition of the urgent need to improve software processes in order to improve the performance of software organizations. Process models are essential in achieving understanding and visibility of processes and are important for other uses including the analysis of processes for improvement. It has been increasingly difficult to compare and evaluate the variety of process modeling formalisms that have appeared in recent years without a clear understanding of precisely for what they will be used. The contribution of this paper is to provide an understanding and a fairly comprehensive catalog of the applications of process modeling for which formalisms may be used. The primary mechanism for doing this is a guided tour of the literature on process modeling supplemented by recent industrial experience. In the paper, basic definitions concerning processes, process descriptions and process modeling are reviewed and then uses of process modeling are surveyed under the following headings: communication among process participants, construction of new processes, control of processes, process· analysis, and process support by automation. Comments are offered on paradigms for process modeling formalisms and directions for future work to permit evolution of a discipline of process engineering are given

Workshop on Modelling of Objects, Components, and Agents, Aarhus, Denmark, August 27-28, 2001

This booklet contains the proceedings of the workshop Modelling of Objects, Components, and Agents (MOCA'01), August 27-28, 2001. The workshop is organised by the CPN group at the Department of Computer Science, University of Aarhus, Denmark and the "Theoretical Foundations of Computer Science" Group at the University of Hamburg, Germany. The papers are also available in electronic form via the web pages: http://www.daimi.au.dk/CPnets/workshop01

Complete Agent-driven Model-based System Testing for Autonomous Systems

In this position paper, a novel approach to testing complex autonomous transportation systems (ATS) in the automotive, avionic, and railway domains is described. It is intended to mitigate some of the most critical problems regarding verification and validation (V&V) effort for ATS. V&V is known to become infeasible for complex ATS, when using conventional methods only. The approach advocated here uses complete testing methods on the module level, because these establish formal proofs for the logical correctness of the software. Having established logical correctness, system-level tests are performed in simulated cloud environments and on the target system. To give evidence that 'sufficiently many' system tests have been performed with the target system, a formally justified coverage criterion is introduced. To optimise the execution of very large system test suites, we advocate an online testing approach where multiple tests are executed in parallel, and test steps are identified on-the-fly. The coordination and optimisation of these executions is achieved by an agent-based approach. Each aspect of the testing approach advocated here is shown to either be consistent with existing standards for development and V&V of safety-critical transportation systems, or it is justified why it should become acceptable in future revisions of the applicable standards.Comment: In Proceedings FMAS 2021, arXiv:2110.1152