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Using Discrete Event Computer Simulation To Analyze The Effects Of Proposed Changes To Personnel In A Hospital Medical Laboratory, Gerardo Morales Aug 2011

Using Discrete Event Computer Simulation To Analyze The Effects Of Proposed Changes To Personnel In A Hospital Medical Laboratory, Gerardo Morales

Theses and Dissertations - UTB/UTPA

A discrete event computer simulation is used to model a portion of the medical laboratory at Doctors Hospital at Renaissance in order to assess the current situation as well as to review the planed personnel changes. The area under observation is the section in which the processor(s) receive, label and distribute the patient samples. There are four cases modeled in the simulation: The main focus is to determine if one or two processors are needed per shift and if the high level of phone calls poses a significant delay to the processors’ workflow. The simulation results indicate that having two …


Anticipating U.S. Population-Level Health And Economic Impacts Using Discrete-Event Simulation To Guide Health Policy Decisions, Odette Reifsnider Aug 2011

Anticipating U.S. Population-Level Health And Economic Impacts Using Discrete-Event Simulation To Guide Health Policy Decisions, Odette Reifsnider

All Dissertations

This dissertation presents two applications of discrete-event simulation (DES) to represent clinical processes: (1) a model to quantify the risk of the maternal obese and diabetic intrauterine environment influence on progression to adult obesity and diabetes, and (2) a model to evaluate health and economic outcomes of different smoking cessation strategies. The first application considers the public health impact of the diabetic and obese intrauterine environment's effect on the prevalence of diabetes and obesity across subsequent generations. We first develop a preliminary DES model to investigate and characterize the epidemiology of diabetes during pregnancy and birth outcomes related to maternal …


A Water Distribution And Treatment Simulation For Testing Cyber Security Enhancements For Water Sector Scada Systems., Justin Robert Adams Jul 2011

A Water Distribution And Treatment Simulation For Testing Cyber Security Enhancements For Water Sector Scada Systems., Justin Robert Adams

Electronic Theses and Dissertations

Supervisory control and data acquisition (SCADA) systems are used by many critical infrastructures including electric power production and distribution, water and waste water treatment, rail transportation, and gas and oil distribution. Originally isolated proprietary systems, SCADA systems are increasingly connected to enterprise networks and the Internet and today use commercial hardware and software. As a result SCADA systems now face serious cyber-security threats. The need for testing and evaluation of developed cyber-security solutions presents a challenge since evaluation on actual systems is usually not possible and building complete physical testbeds is costly. This thesis presents the design and development of …


Development Of An Optimal Replenishment Policy For Human Capital Inventory, Bruce A Holt May 2011

Development Of An Optimal Replenishment Policy For Human Capital Inventory, Bruce A Holt

Doctoral Dissertations

A unique approach is developed for evaluating Human Capital (workforce) requirements. With this approach, new ways of measuring personnel availability are proposed and available to ensure that an organization remains ready to provide timely, relevant, and accurate products and services in support of its strategic objectives over its planning horizon. The development of this analysis and methodology was established as an alternative approach to existing studies for determining appropriate hiring and attrition rates and to maintain appropriate personnel levels of effectiveness to support existing and future missions.

The contribution of this research is a prescribed method for the strategic analyst …


Agent-Based Under Hood Packing, Karthik Ravindranath May 2011

Agent-Based Under Hood Packing, Karthik Ravindranath

All Theses

Improving vehicle performance and passenger comfort has been a prime engineering concern and focus of research for many years in automotive design. Turning to high-performance components in an effort to improve vehicle performance alone is often not enough and their placement and interactions with other components should also be an integral part of the improvement process. With the advancement in hybrid electric vehicle technology, the packing of components under the hood is ever more essential and challenging. Under hood packing is a multi-objective optimization problem with many, and mostly conflicting objectives. A non-deterministic multi-objective evolutionary algorithm needs to be integrated …


Methods Development And Force Field Evaluation For Molecular Simulations Of Interactions Between Structured Peptides And Functionalized Material Surfaces, Galen Collier May 2011

Methods Development And Force Field Evaluation For Molecular Simulations Of Interactions Between Structured Peptides And Functionalized Material Surfaces, Galen Collier

All Dissertations

The process of protein adsorption to material surfaces is highly complex and it is one of the most fundamental concepts upon which progress in the field of bioengineering is based. The strategic design of material surfaces for optimal utility in specific biological environments is absolutely dependent upon a thorough understanding of the mechanisms underlying protein adsorption, yet there is still a very limited understanding of these mechanisms. The primary reason for this lack of understanding is that protein adsorption is a dynamic process which occurs at the atomic and macromolecular scale, where experimental analyses provide a view that is static …


Optical-Wimax Hybrid Networks, Abdou R. A. Ahmed Apr 2011

Optical-Wimax Hybrid Networks, Abdou R. A. Ahmed

Electronic Thesis and Dissertation Repository

The emergence of bandwidth-intensive Internet services, such as
circuit-quality voice transfer and interactive video gaming, create
a high demand for a very qualified next-generation access network.
In addition to high bandwidth, these future access networks should
also provide improved network availability, flexibility, mobility,
reliability, failure protection, quality of service (QoS) support
and cost-effective access. The integration between optical networks
and Worldwide Interoperability for Microwave Access (WiMAX) is a
promising solution for future access networks. Accordingly, a few
different architectures and MAC protocol components have recently
been proposed for the integration between the Ethernet Passive
Optical Network (EPON) and WiMAX. However, …


Evaluation System Design And Academic Performance Analysis Using Clustering And Simulation, Volkan Cakir Apr 2011

Evaluation System Design And Academic Performance Analysis Using Clustering And Simulation, Volkan Cakir

Engineering Management & Systems Engineering Theses & Dissertations

The starting point of this study was to understand the possible causes of evaluation system change in a military academic environment. With that motivation the objectives of this study were defined as examining student profiles in a military academy, establishing the nature of academic performance, comparing student groups that were identified by course scores, analyzing student performance changes over time and developing a manageable evaluation system and curriculum by comparing different scenarios.

An analysis was performed on the literature on academic performance prediction, cluster analysis methodologies and their development, and specifically summarized cluster analytic academic performance studies where these two …


Discrete Event Simulation Manual: Manufacturing Applications, Brian T. Hughes Mar 2011

Discrete Event Simulation Manual: Manufacturing Applications, Brian T. Hughes

Industrial and Manufacturing Engineering

Simulation, specifically discrete event simulation, is a useful tool for industrial and manufacturing engineers when dealing with system analysis. Currently, manufacturing engineers are only exposed to simulation for only a few weeks of their curriculum at Cal Poly. A series of labs are directed by a teacher’s assistant on how to complete a successful simulation experiment. However, there is no text available for student use during this demanding learning period. The simulation learning process involves learning a software program called ProModel, which students with little experience are expected to code, run, and interpret data from complex systems. By creating a …


Integration Of Aeroservoelastic Properties Into The Nasa Dryden F/A-18 Simulator Using Flight Data From The Active Aeroelastic Wing Program, Alexander Wong Chin Mar 2011

Integration Of Aeroservoelastic Properties Into The Nasa Dryden F/A-18 Simulator Using Flight Data From The Active Aeroelastic Wing Program, Alexander Wong Chin

Master's Theses

Aircraft structures have varying stiffness levels making them flexible. Consequently, this elastic property becomes increasingly important at high speeds affecting the flight dynamics of the aircraft. In high speed aircraft such as the F/A-18, elastic structural properties must be accounted for to ensure confidence in predicted flight dynamics in order to avoid adverse aeroelastic phenomena throughout flight.

Data from the F/A-18 Active Aeroelastic Wing (AAW) program was used to create aeroservoelastic (ASE) models at varying flight conditions. The discretized ASE models were integrated into the NASA Dryden F/A-18 simulator in parallel with the traditional 6-DOF (degrees-of-freedom) flight dynamics calculations to …


Simulation And Control Of A Quadrotor Unmanned Aerial Vehicle, Michael David Schmidt Jan 2011

Simulation And Control Of A Quadrotor Unmanned Aerial Vehicle, Michael David Schmidt

University of Kentucky Master's Theses

The ANGEL project (Aerial Network Guided Electronic Lookout) takes a systems engineering approach to the design, development, testing and implementation of a quadrotor unmanned aerial vehicle. Many current research endeavors into the field of quadrotors for use as unmanned vehicles do not utilize the broad systems approach to design and implementation. These other projects use pre-fabricated quadrotor platforms and a series of external sensors in a mock environment that is unfeasible for real world use. The ANGEL system was designed specifically for use in a combat theater where robustness and ease of control are paramount. A complete simulation model of …


Accelerated Simulation And Testing Of Integrated Circuits Using High Performance Computing Machines, Matthew C. Markulik Jan 2011

Accelerated Simulation And Testing Of Integrated Circuits Using High Performance Computing Machines, Matthew C. Markulik

Open Access Theses & Dissertations

As Moore's Law continues to hold true and transistor density becomes exponentially larger the need to rely on computer aided design (CAD) simulators has become more relevant and necessary. As we dive into the age of electronic reliance there presents a need to constantly improve methods to reduce time-to-solution for developing technologies. The reliance on CAD simulators for electronic development leaves engineers with an ability to improve the design process by improving these simulators or improving the methods in which these simulators are being utilized. With the advancement of quality fabrication processes and the ability to operate at sub-threshold levels …


Methodology To Convert A Transportation Planning Origin-Destination Matrix Into A Microscopic Traffic Simulation Origin-Destination Matrix, Jose Osiris Vidana-Bencomo Jan 2011

Methodology To Convert A Transportation Planning Origin-Destination Matrix Into A Microscopic Traffic Simulation Origin-Destination Matrix, Jose Osiris Vidana-Bencomo

Open Access Theses & Dissertations

Microscopic traffic simulation (MTS) is a cost-effective approach for the evaluation of traffic conditions in urban highways networks. In MTS models, traffic demand that is entered into the network is specified by one or several Origin-Destination (O-D) matrices. A major challenge in the application of MTS for large urban networks is the specification of the O-D matrices. This dissertation proposes a methodology that may be used to transform a O-D matrix from a transportation planning model (which is based on Traffic Analysis Zone, or TAZ, and is readily available) into a O-D matrix for a MTS model (which is traffic …


Asymmetric Passive Dynamic Walker Used To Examine Gait Rehabilitation Methods, John Sushko Jan 2011

Asymmetric Passive Dynamic Walker Used To Examine Gait Rehabilitation Methods, John Sushko

USF Tampa Graduate Theses and Dissertations

Testing gait rehabilitation devices on humans can be a difficult task, due to the effects of the neurological controls of the human body. This thesis advances the use of a passive dynamic walker (PDW) tuned to have asymmetric gait patterns similar to those with physical impairments to test rehabilitation devices. A passive dynamic walker is a multipendulum system that has a stable gait pattern when walking down a slope without any energy inputs except the forces due to gravity. A PDW model is better suited for testing rehabilitation devices because it has been shown to resemble human gait and separates …


Integrating Demand And Traffic Simulation Modeling To Evaluate Adaptive Evacuation Plans, Thomas Jude Montz, Jr. Jan 2011

Integrating Demand And Traffic Simulation Modeling To Evaluate Adaptive Evacuation Plans, Thomas Jude Montz, Jr.

LSU Master's Theses

Significant efforts are currently being made by transportation officials to improve the planning and preparation of mass evacuations. The idea of adaptive evacuation plans is an avenue of research that could help improve future evacuation processes. Adaptive evacuation plans stem from the observation that different disaster threat scenarios require different evacuation responses. While adaptive evacuation planning can be generalized to any form of evacuation planning, this project focused on adaptive planning in the context of a hurricane evacuation.

This project was the first to adapt the demand models of Fu, et al, and Cheng, et al, into a regional-scale traffic …


Effects Of Large-Scale Transient Loading And Waste Heat Rejection On A Three Stream Variable Cycle Engine, Michael William Corbett Jan 2011

Effects Of Large-Scale Transient Loading And Waste Heat Rejection On A Three Stream Variable Cycle Engine, Michael William Corbett

Browse all Theses and Dissertations

The objective of the research presented in this document was to gain an understanding of the feasibility of extracting large amounts of transient shaft power from a variable cycle engine and to reject waste heat into the third stream bypass duct. This first required the development of a transient engine and controller simulation. After performing basic verification of the model, such as ensuring conservation of mass, tests were run for three missions using a low-efficiency periodic load which both required shaft power and created low quality waste heat. The waste heat generated by that load was lifted by a cooling …


Analyses Of Variable Refrigerant Flow And Exergy In Air Conditioning Systems, Rashid Ali Alshatti Jan 2011

Analyses Of Variable Refrigerant Flow And Exergy In Air Conditioning Systems, Rashid Ali Alshatti

USF Tampa Graduate Theses and Dissertations

This thesis consists of two research problems in the air conditioning (A/C) area. For the first problem, the aim is to model and simulate a variable refrigerant flow (VRF) air conditioning system. The coefficient of performance (COP) for refrigeration or heat pump system is one of the critical parameters for designing an air conditioning system. The modeling of the system components for a VRF cycle under different cooling conditions using R-134a and R-22 as refrigerants was carried out. Calculations were performed by varying different parameters such as condenser and evaporator temperatures, and refrigerant type. The R-134a refrigerant shows a better …


Operational Performance Evaluation Of Four Types Of Exit Ramps On Florida's Freeways, Linjun Lu Jan 2011

Operational Performance Evaluation Of Four Types Of Exit Ramps On Florida's Freeways, Linjun Lu

USF Tampa Graduate Theses and Dissertations

This research focuses primarily on the analysis of exit ramp performance related to safety and operations. The safety analysis focuses on the impacts of different exit ramp types for freeway diverge areas and different factors contributing to the crashes that occur on the exit ramp sections. The operational analysis is based mainly on simulations by TSIS-CORSIM. Different ramp effects and guidance for selecting optimal exit ramp type are concluded. Issues related to ramp sections and crossroad sections are also demonstrated. Minimum ramp length and minimum distance between ramp terminal and downstream or upstream intersections are calculated. The operational analysis was …


Development And Validation Of Biomechanical Models To Quantify Horse Back Forces At The Walk In Three Horse Breeds, Laxmi Raghunandana Kaidapuram Jan 2011

Development And Validation Of Biomechanical Models To Quantify Horse Back Forces At The Walk In Three Horse Breeds, Laxmi Raghunandana Kaidapuram

LSU Master's Theses

Therapeutic horseback riding is a common component of physical therapy programs. Quantification of the horse back forces will provide vital information to match therapeutic riders with equine partners. To meet this medical need, a model to quantify the horse back forces from ground reaction forces was developed to test the hypothesis that the forces transferred to a static weight on the horse’s back can be predicted given horse breed and weight. Simultaneous, real time kinetic, kinematic, and back force data on a static weight were collected from 7 adult horses: 3 thoroughbreds, 3 quarter horses, and 1 paso fino. An …