In this paper, we consider a distributed video server environment where video movies need not be stored entirely in one server. Blocks of a video movie are allowed to be distributed and replicated over multiple video servers. Customers are served by one video server. This video server, termed originating server, might have to interact with other servers for downloading missing blocks of the req...

High-level symbolic representations of actions to control the working of autonomous robots are used in all hybrid (reactive and deliberative) robot control architectures. Abstract action representations serve several purposes, such as structuring the control code, optimizing the robot performance, and providing a basis for reasoning about future robot action. The paper presents results about re...

When observational data is available from practical studies and a directed cyclic graph for how various variables affect each other is known based on substantive understanding of the process, we consider a problem in which a control plan of a treatment variable is conducted in order to bring a response variable close to a target value with variation reduction. We formulate an optimal control pl...

Robotic devices, such as rovers and autonomous spacecraft, have been successfully controlled by plan execution systems that use plans with temporal flexibility to dynamically adapt to temporal disturbances. To date these execution systems apply to discrete systems that abstract away the detailed dynamic constraints of the controlled device. To control dynamic, under-actuated devices, such as ag...

Study objective: To determine the effect of a symptom-based and a peak flow-based action plan in preventing acute exacerbations in subjects with poorly controlled asthma. Design: A randomized controlled trial in which subjects who had required urgent treatment for their asthma were allocated to receive no action plan, a symptom-based plan, or a peak flow-based action plan. Setting: A university...