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The Autonomous Vehicle Storage and Retrieval System (AVS/RS) with tier-to-tier vehicles is modeled as a semi-open queueing network (SOQN). Different storage/retrieval requests in the AVS/RS are modeled as different classes of customers in the SOQN model. Analyzing multiple configurations of an SOQN via computer simulation is time-consuming. Therefore, this article uses some analytical methods to evaluate the performances of a multi-class, multi-stage SOQN with general service time and interarrival time distributions. Two synchronization policies are also compared and the results show that an AVS/RS with virtual synchronization has a better performance than that with physical synchronization.

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Aurora B kinase is essential in the process of mitosis, and its overexpression has been reported to be associated with a number of solid tumors. We therefore carried out molecular docking, molecular dynamics, and molecular mechanics Poisson-Boltzmann/surface area (MM-PBSA) calculations on several structurally diverse inhibitors (pentacyclic, pyrimidine, quinazoline, and pyrrolopyridine derivatives) and Aurora B kinase to explore the structural and chemical features responsible for the binding recognition mechanism. Molecular simulations reveal that the binding site mainly consists of six binding regions (sites A-F). We have identified that sites B and C are required for optimum binding in Aurora B-inhibitor complexes, sites A and F are needed to improve pharmacokinetic properties, while sites D and E lead to enhanced stability. We verified that hydrogen bonding to the hinge region and hydrophobic contact with the conserved hydrophobic pocket are of critical importance in the systems studied. Specifically, the amino acids Glu171, Phe172, and Ala173 in the hinge region and Leu99, Val107, and Leu223 in the conserved hydrophobic pocket probably account for the high binding affinities of these systems, as shown by hydrogen-bonding analysis and energy decomposition analysis. Hydrophobic contact with Phe172 is also in agreement with experimental data. In addition, the MM-PBSA calculations reveal that the binding of these inhibitors to Aurora B kinase is mainly driven by van der Waals/nonpolar interactions. The findings of this study should help to elucidate the binding pattern of Aurora B inhibitors and aid in the design of novel active ligands.

In this dissertation, we study the performance evaluation of two automated warehouse material handling (MH) technologies -automated storage/retrieval system (AS/RS) and autonomous vehicle storage/retrieval system (AVS/RS). AS/RS is a traditional automated warehouse MH technology and has been used for more than five decades. We show how to model AVSjRSs with tier-to-tier vehicles as SOQNs and evaluate performance of these designs in Chapter 6.AVSjRS is a relatively new automated warehouse design technology. Hence, there are few efficient analytical tools to evaluate performance mea.<;ures of this technology.We developed some efficient algorithms based on SOQN to quickly and effectively evaluate performance of AVSjRS. Additionally, we present a tool that helps a warehouse designer during the concepting stage to determine the type of MH technology to use, analyze numerous alternate warehouse configurations and select one of these for final implementation.VI