As the modern computing environment expands memory hierarchy from CPU registers and local memory to network storage, the optimal goal of a computer architect becomes to design a memory hierarchy that maximizes the overall design of his machine with a minimal cost. This requires deciding on the number, speed and size of the hierarchical layers. As the gap between processor and memory speed is gr...

The application of Queuing Theory to quantify the relationships between trajectory uncertainties due to aviation operations, precision of navigation and control, and traffic flow efficiency in the National Airspace System is discussed. This work builds on a previous research effort on Markovian queuing network models of the NAS. Two approaches for incorporating the trajectory uncertainties in t...

In a supply chain, cross-docking is one of the most innovative systems for ameliorating the operational performance at distribution centers. Cross-docking is a logistics strategy in which freight is unloaded from inbound trucks and (almost) directly loaded into outbound trucks, with little or no storage in between, thus no inventory remains at the distribution center. In this study, we consider...

We present a systematic treatment of efficient nonlinear optimizations of queuing systems. The suite of formulations uses the computational tool of convex optimization, with fast polynomial time algorithms to obtain the global optimum for these nonlinear problems under various constraints. We first show convexity structures of several queuing systems, including some surprising transition patter...

Due to many damages that human activities have imposed on the environment, authorities, manufacturers, and industry owners have taken into account the development of supply chain more than ever. One of the most influential and essential human activities in the supply chain are transportation which green vehicles such as electric vehicles (EVs) are expected to generate higher economic and enviro...

Considering impatient users in space information networks, a preliminary queue congestion control model was presented. It balanced the network loads and make up for the resource lost from the impatient leaving users. To describe the competition among nodes, the model used queuing game theory. The introduced congestion control platform, which consisted of service nodes, calculated user’s gain to...

The problem of staff scheduling at a truck hub for loading and stripping of the trucks is an important and difficult problem to optimize the labor efficiency and cost. The trucks enter the hub at different hours a day, in different known time schedules and operating hours. In this paper, we propose a goal programming to maximize the labor efficiency via minimizing the allocation cost. The propo...

In some environments, mobile robots need to perform docking tasks in a precise manner. In the application domain of this work, an Autonomous Guided Vehicle (AGV), specifically, a fork-lift truck must often perform docking maneuvers to load pallets in conveyor belts. In these maneuvers, the robot motion should be controlled accurately when the mobile robot is close to the target. We propose a mu...