This paper addresses the optimal design and planning of cellulosic ethanol supply chains under economic, environmental, and social objectives. The economic objective is measured by the total annualized cost, the environmental objective is measured by the life cycle greenhouse gas emissions, and the social objective is measured by the number of accrued local jobs. A multiobjective mixed-integer ...

Integrated sites are tightly interconnected networks of large-scale chemical processes. Given the large-scale network structure of these sites, disruptions in any of its nodes, or individual chemical processes, can propagate and disrupt the operation of the whole network. Random process failures that reduce or shut down production capacity are among the most common disruptions. The impact of su...

A new planning method for optimal control of multi-robot systems is discussed which accounts for the (continuous) physical locomotion dynamics of the robots and its tight coupling to the distribution and allocation of (discrete) subtasks to the robots to fulfill a joint mission. The point of departure is a nonlinear and nonconvex hybrid optimal control problem (HOCP) formulation which incorpora...

This paper addresses the problem of developing an optimization structure to aid the operational decision-making in a real-world pipeline scenario. The pipeline connects an inland refinery to a harbor, conveying different types of commodities (gasoline, diesel, kerosene, alcohol, liquefied petroleum gas, etc). The scheduling of activities has to be specified in advance by a specialist, who must ...

This paper presents a polynomial time algorithm used for solving a Mixed Integer Linear Program (MILP) formulation of a scheduling problem applicable to Air Traffic Control. We first relate the general MILP (which we believe to be NP-Hard) to the Air Traffic Control problem, which consists of performing maneuver assignments to achieve scheduling constraints for airport arrival traffic. This MIL...

State-of-the-art baggage handling systems transport luggage in an automated way using destination coded vehicles (DCVs). These vehicles transport the bags at high speeds on a “mini” railway network. In this paper we consider the problem of controlling the route of each DCV in the system. This is a nonlinear, nonconvex, mixed integer optimization problem. Nonlinear model predictive control (MPC)...

Alternatívy k MILP pre rozvrhovanie dávkových banských procesov Cieľom príspevku je navrhnúť možnosť, nahradenia optimalizačných metód na báze zmiešaného celočíselného programovania použitím približných metód rozhodovania (heuristika) v oblasti plánovania a riadenia banských procesov. Výsledkom tohto počítačom podporaovaného plánovania sú detailné výrobné rozvrhy vytvorené podľa požiadaviek ako...

In this paper we present a mixed integer linear programming (MILP) resource allocation model with hard and soft resource constraints for projects. By definition, a hard resource constraint is not resolvable within the given planning horizon, but a soft resource conflict may be managed by a flexible "hiring-firing" strategy. A "well-balanced" optimal schedule for the soft resources is characteri...

In this work, we introduce the multiscale production routing problem (MPRP), which considers the coordination of production, inventory, distribution, and routing decisions in multicommodity supply chains with complex production facilities. We propose an MILP model involving two different time grids. While a detailed mode-based production scheduling model captures all critical operational constr...

This paper presents a receding horizon controller (RHC) that can be used to design trajectories for an aerial vehicle flying through a three dimensional terrain with obstacles and no-fly zones. To avoid exposure to threats, the paths are chosen to stay as close to the terrain as possible, but the vehicle can choose to pop-up over the obstacles if necessary. The approach is similar to our previo...