Railway interlocking system is a safety critical system. Its failure can cause the loss of human life, severe injuries and loss of money. Therefore the complication of this type of system requires advanced methodologies, which provide complete security and quality of a system. One way of achieving this goal is by using formal methods, which are mathematically based languages, techniques and too...

A new approach for the automatic equivalence checking of behavioral or structural descriptions of designs with complex control is presented. The veriication tool combines symbolic simulation with a hierarchy of equivalence checking methods, including decision-diagram based techniques, with increasing accuracy in order to optimize overall veriication time without giving false negatives. The equi...

The growth of manufacturing control software from simple NC and PLC-based systems to concurrent networked systems incorporating PC’s, PLC’s and CNC’s has created new challenges to the maintenance of safe and dependable manufacturing operations. Key milestones in this evolution, and the prospects for the use of formal verification methods in achieving enhanced dependability of future manufacturi...

Active Spaces are physical spaces, rich in heterogeneous computing and communication devices, with supporting software services to facilitate collaboration between users and interaction with the space. Such spaces are usually shared by different groups of users, for different types of applications. Access control techniques for these “intelligent” environments must recognize the existence of ta...

We propose an access control model specifically developed to support fine-grained response actions, such as request suspension and request tainting, in the context of an anomaly detection system for databases. To achieve such response semantics, the model introduces the concept of privilege states and orientation modes in the context of a role-based access control system. The central idea in ou...

In formal concept analysis, it is well-known that the number of concepts can be exponential in worst case. To analyze average case, we introduce a probabilistic model for random contexts and prove has superpolynomial asymptotic lower bound.

A new control software development method is presented. It uses IEC 61499 function blocks for control software programming and provides tools for simulation, execution, automatic model generation and formal verification of the control code during the development. Simulation and execution are supported by the same tool, the Fuber runtime environment. Formal modeling is done using extended finite...

Recently, many critical control systems are developed using formal methods. When software applied to such systems is developed, the employment of formal methods in the software requirements specification and verification will provide increased assurance for such applications. Earlier error of overlooked requirement specification can be detected using formal specification method. Also the testin...