Ambient assisted living and smart home technologies are a good way to take care of dependent people whose number will increase in the future. They allow the discovery and the recognition of human's activities of daily living (ADLs) in order to take care of people by keeping them in their home. In order to consider the human behavior nondeterminism, probabilistic approaches are used despite difficulties encountered in model generation and probabilistic indicators computing. In this article, a global method based on probabilistic finite-state automata and the definition of the normalized likelihood and perplexity is proposed to manage ADLs discovery and recognition. In order to reduce the computational complexity, some results about a simplified normalized likelihood computation are proved. A real case study showing the efficiency of the proposed method is discussed.

Numerous theoretical results have been obtained in the field of conformance testing, a very promising formal technique to improve dependability of critical systems. Nevertheless, developing on this basis programmable logic controller (PLC) test techniques that produce correct conformance verdicts requires to take into account the real technological features of PLC. This paper proposes conformance relations that meet this objective. Examples illustrate the benefits of the contribution.

Monitoring Activities of Daily Living (ADL) has become a major occupation to respond to the aging population and prevent frailty. To do this, the scientific community is using Machine Learning (ML) techniques to learn the lifestyle habits of people at home. The most-used formalism to represent the behaviour of the inhabitant is the Hidden Markov Model (HMM) or Probabilistic Finite Automata (PFA), where events streams are considered. A common decomposition to design ADL using a mathematical model is Activities–Actions–Events (AAE). In this paper, we propose mathematical criteria to evaluate a priori the performance of these instrumentations for the goals of ADL recognition. We also present a case study to illustrate the use of these criteria.

In this paper, we consider multi-robot path planning problems for high-level tasks with a finite horizon. In many situations, there is a need to count how many times a sub-task is satisfied in order to achieve the overall task. However, existing temporal logic languages, such as linear temporal logic, is not efficient in describing such requirements. To address this issue, we propose a new temporal logic language called Counting Time Temporal Logic (CTTL) that extends linear temporal logic by explicitly counting the number of times that some tasks are satisfied. To solve the CTTL path planning problem, we propose an efficient integer linear programming-based method to encode task satisfaction. We show that our approach is both sound and complete, while achieving higher efficiency than direct encodings of such requirements. Moreover, we study several variants of the problem. To validate our results, we present several numerical experiments to show the scalability of the proposed approach and a simulation case study of a team of autonomous robots to illustrate the feasibility of the synthesis procedure. Finally, to evaluate the real-world feasibility of our method, we conduct a hardware experiment with two Turtlebot3-Burger mobile robots.