In this paper, we study optimal LQG tracking control problems for linear discrete-time hybrid systems. We adopt an approach to prepare some candidates of mode distributions and minimize value functions at each time for the systems and performance indices. By the approach, system states and mode distributions are simultaneously optimized so that performance indices are minimized for causal information of reference signals. We consider optimization problems for averaged systems and averaged performance indices throughout mode distributions. Finally, we give numerical examples and verify that we can obtain both optimal tracking performance and optimal candidate of mode distributions by the algorithm presented in this paper.
In this paper, we develop a dynamic model and a solution procedure for maximal covering location problem with backup services for locating emergency facilities like fire stations. In this study, two main concepts are used to model a real life condition to improve the service level for demand nodes. These concepts are modular arrangement of different fire trucks and ambulances, as an example for modules, and backup services for demand nodes. The mathematical model is a pure 0-1 integer programming problem. To solve the problem, an efficient genetic algorithm is used because the algorithm has appeared as a strong method to solve integer programning problems. Some test problems are generated and solved by CPLEX, GA and a developed heuristic to be able to compare the results with managerial insights.
Power-assisted wheelchairs that assists the driving torque by electric motors are effective for the daily life of elderly people and handicapped people, however, the users with unbalanced force of right and left arms due to some disability are difficult to drive as he/she requests. Therefore this paper proposes a driving control system of power-assisted wheelchairs with the target position estimation based on the individual operation characteristics model. In addition, an operation training system by visual feedback to improve the user’s proficiency is also proposed. Some experiment results are provided to show the effectiveness of the proposed driving control system and training system.