Abstract-The pacemaker challenge proposed by Software Quality Research Laboratory is looking for formal methods to produce precise and reliable systems. Safety critical systems like pacemaker need to guarantee important properties (like deadlock-free, safety, etc.), which concern human lives. Formal methods have been applied in designing safety critical systems with verified desirable properties. In this paper, we propose a formal model of pacemaker, modeling its behaviors and its communication with the external environment, using a realtime formalism. Critical properties, such as deadlock freeness and heart rate limits are then verified using the model checker PAT(Process Analysis Toolkit). This work yields a verified formal model of pacemaker systems, which can serve as specification for real pacemaker implementations.

Recently, in Vietnam, the detection of geodetic measurements that contain rough errors as well as such data processing method has been considered as a key step in geodetic data processing, especially for large geodetic networks with many different types of measurements like 3D - Global Navigation Satellite Systems (GNSS) network. On the other hand, mines in Vietnam often have complex terrains, so it is necessary to apply modern and flexible surveying methods in combination with ground and space measurements to build 3D coordinates control networks for management and exploitation to ensure sustainable development. Therefore, this research developed a Robust estimation method based on empirical weighting function for establishing 3D geodetic network combining terrestrial observation and GNSS vectors. The experiment on processing the combined network in Lang Son limestone quarry, Vietnam showed that the proposed method could be an effective solution for processing 3D terrestrial – GNSS geodetic network for mine surveying in Vietnam.

Security protocols play more and more important role nowadays, ranging from banking to electronic commerce systems. They are designed to provide properties such as authentication, key exchanges, key distribution, non-repudiation, proof of origin, integrity, confidentiality and anonymity, for users who wish to exchange messages over a medium over which they have little control. These properties are often difficult to characterize formally (or even informally). The protocols themselves often contain a great deal of combinatorial complexity, making their verification extremely difficult and prone to error. To overcome these obstacles, many different approaches are proposed such as using theorem provers or ranking systems. However, they are lack of automation, sufficiency in demand or time verification. In this paper, we will propose an approach using Real Time System (RTS) and an model checker PAT to deal with these problems.