Nowadays, the importance of *operations research* is unquestionable since this field has a very significant contribution in finding and identifying the best decisions in many real-life situations. Operations research provides the tools to model and to solve problems of various kinds where decisions have to be made and the best one(s) has to be identified. For example, in making the best decision and determining at the same time numerical parameters in the engineering design of a schedule for machine use in a factory, or schedule of public traffic (planes train, busses, etc). Also routing problems like the design of wireless networks for telecommunication, delivery routes, etc. are important examples.

The concept of *best decision *depends of course on the problem considered and is not easy to define mathematically. The most common way to do this is to describe a decision as a set of parameters called *decision variables*, and try to minimize (or maximize) an *objective function *depending on these variables. This function may, for example, compute the cost associated with the decision. Most times certain combinations of parameters are not allowed (e.g. physical dimensions cannot be negative, a system must satisfy some performance requirements, etc), which leads us to consider a set of constraints acting on the decision variables.

*Operations research *cannot be separated from the world of o*ptimization, *since* optimization *is the field of mathematics whose goal is to minimize or maximize an objective function depending on several decision variables under a set of constraints.

In this RWS, we shall promote the importance of these two fields by giving introductory and advance lecturers with applications on OROM in two days. The lectures will also prepare for projects that will be executed by the participants of the RWS. For this 3rd RWS of OROM, the applied topics will be in **Physics Engineering and Material Sciences Modelling.**

DOWNLOAD LEAFLET: Leaflet_3rd_RWS_OROM2016