GPU accelerated Hungarian algorithm for traveling salesman problem

In this thesis, we present a model of the Traveling Salesman Problem (TSP) cast in a quadratic assignment problem framework with linearized objective function and constraints. This is referred to as Reformulation Linearization Technique at Level 2 (or RLT2). We apply dual ascent procedure for obtaining lower bounds that employs Linear Assignment Problem (LAP) solver recently developed by Date(2016). The solver is a parallelized Hungarian Algorithm that uses Compute Unified Device Architecture (CUDA) enabled NVIDIA Graphics Processing Units (GPU) as the parallel programming architecture. The aim of this thesis is to make use of a modified version of the Dual Ascent-LAP solver to solve the TSP. Though this procedure is computational expensive, the bounds obtained are tight and our experimental results confirm that the gap is within 2% for most problems. However, due to limitations in computational resources, we could only test problem sizes N < 30. Further work can be directed at theoretical and computational analysis to test the efficiency of our approach for larger problem instances

Effects of EHR System Change on Nurse and Physician Perceived Workload and EHR Usability in Urgent/Convenient Care Clinics

A previous pre-post pilot intervention study using the NASA-TLX, System Usability Scale, and time-motion measures found that after Urgent/Convenient Care clinics (UCC) made the switch from a hybrid paper and electronic health record (H-HER) to a meaningful use EHR system (MU-EHR), physician staff perceived an increase in workload, while nursing staff expressed less perceived changes in workload. Decreased usability ratings that accompanied the introduction of the MU-EHR system suggest that increased workload could be explained by its increased difficulty of use compared to its predecessor, the hybrid system. The National Institute of Standards and Technology (NIST) has issued a document for the Technical Evaluation, Testing, and Validation of the Usability of Electronic Health Records, which includes a comprehensive checklist for Expert Review of EHR, which we condensed and adapted to fit Nielsens 10 Usability Heuristics. We will use this checklist to conduct two tasks: (1) a Heuristic evaluation (HE) of an EHR interface, as it is used to conduct certain tasks by physicians and by nurses; (2) A structured observation of typical UCC clinical tasks as performed by an expert physician and expert nurse user of the vendordesigned EHR system, in order to create a cognitive task analysis of each task. The HE allows us to explore usability issues more directly, while the structured observation helps us quantify the amount of work completed. We hope that together, these two evaluation activities will help us interpret physicians and nurses previous self-reports of usability and workload.Ope