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Full-Text Articles in Engineering

Accelerating Finite State Projection Through General Purpose Graphics Processing, Thomas Trimeloni Apr 2011

Accelerating Finite State Projection Through General Purpose Graphics Processing, Thomas Trimeloni

Theses and Dissertations

The finite state projection algorithm provides modelers a new way of directly solving the chemical master equation. The algorithm utilizes the matrix exponential function, and so the algorithm’s performance suffers when it is applied to large problems. Other work has been done to reduce the size of the exponentiation through mathematical simplifications, but efficiently exponentiating a large matrix has not been explored. This work explores implementing the finite state projection algorithm on several different high-performance computing platforms as a means of efficiently calculating the matrix exponential function for large systems. This work finds that general purpose graphics processing can accelerate …


Electromagnetic And Heat Transfer Modeling Of Microwave Heating In Domestic Ovens, Krishnamoorthy Pitchai Apr 2011

Electromagnetic And Heat Transfer Modeling Of Microwave Heating In Domestic Ovens, Krishnamoorthy Pitchai

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Microwave (MW) ovens are used extensively for heating a variety of not-ready-to-eat food products. It is vital to achieve target temperature uniformly throughout the food to inactivate foodborne pathogens to assure safety. Non-uniform heating of foods in microwave ovens is the major concern in assuring microbiological safety of such products. The non-uniform heating of foods in domestic microwave ovens is due to complex interactions of microwaves with foods. A comprehensive coupled electromagnetic and heat transfer model was developed using finite-difference time-domain based numerical method to understand the complex interaction of microwaves with foods. Simulation parameters such as cell size, heating …


Modeling And Performance Investigation Of A Rotor With Dissimilar Bearing Support System, Yunlu Li Jan 2011

Modeling And Performance Investigation Of A Rotor With Dissimilar Bearing Support System, Yunlu Li

ETD Archive

Different types of bearings have different dynamic characteristics. By using one type of bearing at one end of a rotor and another type of bearing at the other end of the rotor, it is possible to exploit the advantages of both types in the same system. One example of such combination is a bronze bushing and active magnetic bearing (AMB). In the available literature, there are examples of such systems but are not fully explored with regard to how to model the system to fully utilize both support type properties. This thesis investigates the modeling and performance of such a …


Model Identification, Updating, And Validation Of An Active Magnetic Bearing High-Speed Machining Spindle For Precision Machining Operation, Adam C. Wroblewski Jan 2011

Model Identification, Updating, And Validation Of An Active Magnetic Bearing High-Speed Machining Spindle For Precision Machining Operation, Adam C. Wroblewski

ETD Archive

High-Speed Machining (HSM) spindles equipped with Active Magnetic Bearings (AMBs) are envisioned to be capable of autonomous self-identification and performance self-optimization for stable high-speed and high quality machining operation. High-speed machining requires carefully selected parameters for reliable and optimal machining performance. For this reason, the accuracy of the spindle model in terms of physical and dynamic properties is essential to substantiate confidence in its predictive aptitude for subsequent analyses.This dissertation addresses system identification, open-loop model development and updating, and closed-loop model validation. System identification was performed in situ utilizing the existing AMB hardware. A simplified, nominal open-loop rotor model was …


Dye Waste Treatment, Siew Teng Ong, Pei Sin Keng, Weng Nam Lee, Sie Tiong Ha, Yung Tse Hung Jan 2011

Dye Waste Treatment, Siew Teng Ong, Pei Sin Keng, Weng Nam Lee, Sie Tiong Ha, Yung Tse Hung

Civil and Environmental Engineering Faculty Publications

© 2011 by the authors. Dye wastes represent one of the most problematic groups of pollutants because they can be easily identified by the human eye and are not easily biodegradable. This literature review paper highlights and provides an overview of dye waste treatments performed over the three years period from 2008-2010. Noteworthy processes for the treatment of dye waste include biological treatment, catalytic oxidation, filtration, sorption process and combination treatments.


Modeling And Quantitative Analysis Of White Matter Fiber Tracts In Diffusion Tensor Imaging, Xuwei Liang Jan 2011

Modeling And Quantitative Analysis Of White Matter Fiber Tracts In Diffusion Tensor Imaging, Xuwei Liang

University of Kentucky Doctoral Dissertations

Diffusion tensor imaging (DTI) is a structural magnetic resonance imaging (MRI) technique to record incoherent motion of water molecules and has been used to detect micro structural white matter alterations in clinical studies to explore certain brain disorders. A variety of DTI based techniques for detecting brain disorders and facilitating clinical group analysis have been developed in the past few years. However, there are two crucial issues that have great impacts on the performance of those algorithms. One is that brain neural pathways appear in complicated 3D structures which are inappropriate and inaccurate to be approximated by simple 2D structures, …


Model Development Of A Virtual Learning Environment To Enhance Lean Education, Akalpit Gadre, Elizabeth Cudney, Steven Corns Jan 2011

Model Development Of A Virtual Learning Environment To Enhance Lean Education, Akalpit Gadre, Elizabeth Cudney, Steven Corns

Engineering Management and Systems Engineering Faculty Research & Creative Works

Modern day industry is becoming leaner by the day. This demands engineers with an in-depth understanding of lean philosophies. Current methods for teaching lean include hands-on projects and simulation. However, simulation games available in the market lack simplicity, ability to store the results, and modeling power. the goal of this research is to develop a virtual simulation platform which would enable students to perform various experiments by applying lean concepts. the design addresses these deficiencies through the use of VE-Suite, a virtual engineering software. the design includes user-friendly dialogue boxes, graphical models of machines, performance display gauges, and an editable …


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 …


Monitoring, Diagnosis, And Control For Advanced Anesthesia Management, Zhibin Tan Jan 2011

Monitoring, Diagnosis, And Control For Advanced Anesthesia Management, Zhibin Tan

Wayne State University Dissertations

Modern anesthesia management is a comprehensive and the most critical issue in medical care. During the past dacades, a large amount of research works have been focused on the problems of monitoring anesthesia depth, modeling the dynamics of anesthesia patient for the purpose of control, prediction, and diagnosis.

Monitoring the anesthesia depth is not only for keeping the patient in adquate anesthesia level but also for preventing the patient from overdosing. Several EEG based indexes have been developed such as the BIS, and Entropy etc. for measuring depth. However, reports mentioned that those indexes in some cases fail in detecting …


Use Of Innovative Computer Technology And Optical Texture Properties In The Analysis Of Pavement Digital Images, Saumya Priyadari Amarasiri Jan 2011

Use Of Innovative Computer Technology And Optical Texture Properties In The Analysis Of Pavement Digital Images, Saumya Priyadari Amarasiri

USF Tampa Graduate Theses and Dissertations

Digital image based automated pavement crack detection and classification technology has seen vast improvements in the recent years. In spite of these developments, although pavement crack lengths and widths can be evaluated using state-of-the-art software with a reasonable accuracy, no reported evidence is found in extending this technology to evaluate crack depths. Hence a preliminary study was carried out to model the digital image formation of cracked concrete pavements based on the Bidirectional Reflection Distribution Function. It was revealed that a definitive theoretical relationship exists among the crack widths and depths and the maximum pixel intensity contrasts in the images …


Modeling Heat Transfer During Cooling Of Ready-To-Eat Meat And Poultry Products Using Three-Dimensional Finite Element Analysis And Web-Based Simulation, Jihan F. Cepeda Jimenez Dec 2010

Modeling Heat Transfer During Cooling Of Ready-To-Eat Meat And Poultry Products Using Three-Dimensional Finite Element Analysis And Web-Based Simulation, Jihan F. Cepeda Jimenez

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The meat industry is required to comply with processing performance standards for preventing the growth of foodborne pathogens in products. These performance standards, established by the United States Department of Agriculture - Food Safety and Inspection Service (USDA-FSIS) require a reduction of Salmonella spp (lethality standard) and limit the growth of sporeforming bacteria (stabilization standard) in certain processed meat products. In general, strategies used to comply with these standards are associated with thermal processing. Meat processors have difficulties complying with these performance standards. Moreover, thermal processing deviations are an issue in the meat industry that generate uncertainty regarding the safety …


A Numerical And Experimental Study Of Differential Settling In Cohesive Sediment, Chad Heiliger Dec 2010

A Numerical And Experimental Study Of Differential Settling In Cohesive Sediment, Chad Heiliger

All Theses

Accurate sedimentation modeling has important applications in a number of fields. This includes modeling the accumulation of sediment in harbor channels and modeling the sedimentation and accumulation of particles in retention ponds in the still waters behind dams in order to calculate the trap efficiency. By accurately modeling sedimentation, engineering failures such as the 2008 TVA spill at the Kingston Fossil Plant could possibly be avoided. Three different numerical models comparing the settling rates of individual particles in quiescent waters were created to compare the change of settling velocity due to particle size distributions, change of local concentrations, and flocculation …


Modeling And Simulation Of Autonomous Thermal Soaring With Horizon Simulation Framework, Zhenhua Li Dec 2010

Modeling And Simulation Of Autonomous Thermal Soaring With Horizon Simulation Framework, Zhenhua Li

Master's Theses

A thermal is a column of warm rising air triggered by differential heating on the ground. In recent studies UAVs were programmed to exploit this free atmospheric energy from thermals to improve their range and endurance. Researchers had successfully flown UAVs autonomously with thermal soaring method. Most research involved some form of flight simulation. Improvements to the aircraft and thermal models for simulation purpose would enable researchers to better design their UAVs and explore any potential flaws in their designs. An aircraft simulation with a thermal environment was created in Horizon Simulation Framework, a modeling and verification framework that was …


Modeling The Random Component Of Manufacturing Yield Of Integrated Circuits., David L. Farnsworth, Michael E. Long Dec 2010

Modeling The Random Component Of Manufacturing Yield Of Integrated Circuits., David L. Farnsworth, Michael E. Long

Articles

A model is created for the number of integrated circuits that are good from each wafer on which they are fabricated. The goal is to separate the random or common cause loss from the systematic or special loss. The random loss from this type of process is modeled so that false alarms indicating systematic loss are less likely to occur and so that the structure of the systematic loss can be determined.


The Development And Validation Of A Finite Element Model Of A Canine Rib For Use With A Bone Remodeling Algorithm., Scott J. Sylliaasen Dec 2010

The Development And Validation Of A Finite Element Model Of A Canine Rib For Use With A Bone Remodeling Algorithm., Scott J. Sylliaasen

Master's Theses

Studies are currently being performed to determine the effects of bisphosphonate treatments on the structure and density of bone tissue. One of the pathways for gaining a better understanding of the effects of this and other treatments involves creating a computer simulation. Theory suggests that bone tissue structure and density are directly related to the manner in which the tissue is loaded. Remodeling is the process in which bone tissue is resorbed in areas of low stress distributions, and generated in areas of high stress distributions. Previous studies have utilized numerical methods and finite element methods to predict bone structure …


Dual-Scale Modeling Of Two-Phase Fluid Transport In Fibrous Porous Media, Alireza Ashari Nov 2010

Dual-Scale Modeling Of Two-Phase Fluid Transport In Fibrous Porous Media, Alireza Ashari

Theses and Dissertations

The primary objective of this research is to develop a mathematical framework that could be used to model or predict the rate of fluid absorption and release in fibrous sheets made up of solid or porous fibers. In the first step, a two-scale two-phase modeling methodology is developed for studying fluid release from saturated/unsaturated thin fibrous media made up of solid fibers when brought in contact with a moving solid surface. Our macroscale model is based on the Richards’ equation for two-phase fluid transport in porous media. The required constitutive relationships, capillary pressure and relative permeability as functions of the …


Plant Growth Modeling Using L-System Approach And Its Visualization, Atris Suyantohadi, Alfiyan Alfiyan, Mochamad Hariadi, Mauridhi Hery Purnomo Nov 2010

Plant Growth Modeling Using L-System Approach And Its Visualization, Atris Suyantohadi, Alfiyan Alfiyan, Mochamad Hariadi, Mauridhi Hery Purnomo

Makara Journal of Technology

The visualization of plant growth modeling using computer simulation has rarely been conducted with Lindenmayer System (L-System) approach. L-System generally has been used as framework for improving and designing realistic modeling on plant growth. It is one kind of tools for representing plant growth based on grammar sintax and mathematic formulation. This research aimed to design modeling and visualizing plant growth structure generated using L-System. The environment on modeling design used three dimension graphic on standart OpenGL format. The visualization on system design has been developed by some of L-System grammar, and the output graphic on three dimension reflected on …


Picasso Interface For Horizon Simulation Framework, Brian E. Kirkpatrick Aug 2010

Picasso Interface For Horizon Simulation Framework, Brian E. Kirkpatrick

Master's Theses

The Horizon Simulation Framework, or HSF, is a modeling and simulation framework compiled from C/C++ source code into a command line program. Picasso is an interface designed to control the input files to Horizon by providing visual tools to create and manipulate the XML files used to define an HSF system of assets, their environment, and other simulation parameters. Picasso also supports the visualization of Horizon output in several different forms, and import mechanics from online space object catalogues.


Observer Incorporated Neoclassical Controller Design: A Discrete Perspective, Winston Alexander Baker Aug 2010

Observer Incorporated Neoclassical Controller Design: A Discrete Perspective, Winston Alexander Baker

Master's Theses (2009 -)

Control theory has generally been divided into two categories, modern control and classical control. Modern control uses state feedback to alter the pole locations of a given system. Classical control uses pre-compensation to alter the zeroes of the system and uses output feedback to adjust the poles to bring stability to the system. The drawback is that the application of classical control techniques can be a lengthy, complicated and iterative design process and in the end, classical control techniques still do not give information about the state of the system. Neoclassical control combines classical control techniques with the state feedback …


Optimization And Correlation Of The Penn State Model Of Friction Stir Welding To Experimental Welds In 304l Stainless Steel, Devin Donaldson Furse May 2010

Optimization And Correlation Of The Penn State Model Of Friction Stir Welding To Experimental Welds In 304l Stainless Steel, Devin Donaldson Furse

Theses and Dissertations

A numerical model of friction stir welding developed by T. DebRoy, R. Nandan, and others has been optimized to fit experimental data of eleven welds of 304L stainless steel at various weld feed rates and spindle speeds. Optimization was used to determine the values of five difficult-to-measure model parameters. The optimal parameter values were then correlated to the weld machine inputs. The mechanical efficiency and the coefficient of friction were not correlated with feed rate, spindle speed, or axial pressure. Tool slip was positively correlated with feed rate, negatively correlated with spindle speed, and not correlated with axial pressure. The …


Numerical Computation Of Hydrodynamic Behavior Of Biomass Particles In Circulating Fluidized Beds, Afsin Gungor Dr. May 2010

Numerical Computation Of Hydrodynamic Behavior Of Biomass Particles In Circulating Fluidized Beds, Afsin Gungor Dr.

The 13th International Conference on Fluidization - New Paradigm in Fluidization Engineering

A model using a particle based approach is developed to accurately predict the hydrodynamic behavior of biomass particles in CFBs. Generally, the change in the pressure gradient with height in CFB riser is small. Numerical results are in good agreement with experiments, both in form and magnitude.


Implications Of Climate-Driven Variability And Trends For The Hydrologic Assessment Of The Reynolds Creek Experimental Watershed, Idaho, V. Sridhar, Anurag Nayak May 2010

Implications Of Climate-Driven Variability And Trends For The Hydrologic Assessment Of The Reynolds Creek Experimental Watershed, Idaho, V. Sridhar, Anurag Nayak

Civil Engineering Faculty Publications and Presentations

The Soil and Water Assessment Tool (SWAT) model was used to assess the implications of long-term climate trends for the hydroclimatology of the Reynolds Creek Experimental Watershed (RCEW) in the Owyhee Mountains, Idaho of the Intermountain West over a 40- year period (1967-2006). Calibration and validation of the macroscale hydrology model in this highly monitored watershed is key to address the watershed processes that are vulnerable to both natural climate variability and climate change and . The model was calibrated using the streamflow data collected between 1997 and 2006 from the three nested weirs, the Reynolds Mountain East (RME) , …


Mathematical Modeling Of Light Utilization And The Effects Of Temperature Cycles On Productivity In A Steady-State Algal Photobioreactor, Peter Edwin Zemke May 2010

Mathematical Modeling Of Light Utilization And The Effects Of Temperature Cycles On Productivity In A Steady-State Algal Photobioreactor, Peter Edwin Zemke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The work presented here investigated two methods of improving productivity in microalgal photobioreactors: applying temperature cycles intended to maximize photosynthesis and minimize respiration, and development of a mathematical model that predicts improvements in photon utilization using temporal light dilution (flashing).

The experiments conducted on diurnal temperature cycles with Dunaliella tertiolecta in 30-L outdoor photobioreactors showed that a properly chosen temperature cycle can improve mass and energy productivity by 18% over an identical photobioreactor with a constant temperature. However, excessively large temperature cycle amplitudes reduced productivity. A 4-7% increase in energy content was observed in microalgae exposed to temperature cycles. The …


An Exploration Of Formal Methods And Tools Applied To A Small Satellite Software System, Russell J. Grover May 2010

An Exploration Of Formal Methods And Tools Applied To A Small Satellite Software System, Russell J. Grover

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Formal system modeling has been a topic of interest in the research community for many years. Modeling a system helps engineers understand it better and enables them to check different aspects of it to ensure that there is no undesired or unexpected behavior and that it does what it was designed to do. This thesis takes two existing tools that were created to aid in the designing of spacecraft systems and creates a layer to connect them together and allow them to be used jointly. The first tool is a library of formal descriptions used to specify spacecraft behavior in …


Hydrodynamic Modeling Of San Elijo Lagoon, California, Mary Elizabeth Nee Friedmann Bourgoyne Jan 2010

Hydrodynamic Modeling Of San Elijo Lagoon, California, Mary Elizabeth Nee Friedmann Bourgoyne

LSU Master's Theses

Decisions on where to concentrate management efforts need to be guided by an ability to accurately simulate and predict physical and ecological changes. Many restoration projects experience difficulties due to a lack of understanding of the ecological response and evolution of wetland systems (Goodwin et al., 2001). There are several approaches that can be taken in analyzing a system. The appropriate selection should be based on the available data, the spatial scale of the wetland, and the physical processes governing the system (Goodwin and Kamman, 2001). Predictive tools are essential for good long-term management (Goodwin et al., 2001). The objective …


Aircraft Gearbox Dynamics Subject To Electromechanical Actuator Regenerative Energy Flow, Matthew S. Rutledge Jan 2010

Aircraft Gearbox Dynamics Subject To Electromechanical Actuator Regenerative Energy Flow, Matthew S. Rutledge

Browse all Theses and Dissertations

To increase reliability and efficiency, standard aircraft components are being replaced with more electric subsystems aimed to reduce weight, conserve space, and improve energy management. One application of this process replaces standard hydraulic actuators used in flap or aileron movements with electromechanical actuators powered by an external generator. During different types of return movements, the electromechanical actuator will produce regenerative power that flows back through the generator and pulses into the engine-gearbox subsystem. The regenerative power, defined by characteristic amplitude, frequency, and other pulse attributes, coupled with the driving force produced by the engine may dramatically impact the performance and …


Effect Of Magnetron Frequency On Heating Pattern In Domestic Oven, Sohan Birla, Krishnamoorthy Pitchai, Jeyamkondan Subbiah, David D. Jones Jan 2010

Effect Of Magnetron Frequency On Heating Pattern In Domestic Oven, Sohan Birla, Krishnamoorthy Pitchai, Jeyamkondan Subbiah, David D. Jones

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

In this study a computer model was developed to simulate microwave heating of a model food with a range of magnetron frequencies. The range was decided upon performing the frequency spectrum analysis of microwave leakage from the microwave oven. Simulation results showed that the magnetron input as sinusoidal frequency from 2.44 GHz to 2.48 GHz generates different heating profiles. The simulated heating profiles were compared with experimental heating profiles obtained by using an IR camera. None of simulations with individual frequency exactly matches with experimental temperature profile. The closet match between simulated and observed temperature profiles was found with 2.46 …


Slides: Groundwater Declines, Climate Change And Approaches To Adaptation, Katharine Jacobs Jun 2009

Slides: Groundwater Declines, Climate Change And Approaches To Adaptation, Katharine Jacobs

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Katharine Jacobs, Director of the Arizona Water Institute, University of Arizona

37 slides


Effect Of Liquid Dispersion On Corrosion Behavior Of Metals In Gas/Liquid/Solid Multiphase Corrosion Systems, Jing Jiang, Jia Wang May 2009

Effect Of Liquid Dispersion On Corrosion Behavior Of Metals In Gas/Liquid/Solid Multiphase Corrosion Systems, Jing Jiang, Jia Wang

Journal of Electrochemistry

Liquid dispersion,described by the parameters of gas/liquid/solid three-phase boundary(TPB) zone of dispersed liquid on a metal surface,is an important property of liquid state influencing corrosion behavior of metals in gas/liquid/solid multiphase corrosion systems.In our paper,the characterisation of cathodic oxygen reduction process in TPB zone was discussed,and a model describing the cathodic process of TPB zone was developed.On this basis,the relationship between the cathodic limiting current and the TPB parameters was studied,and the simulation results were in good agreement with the experimental data.The role of liquid dispersion in atmospheric and sandy soil corrosion systems was also simulated.


Stochastic Spatio-Temporal Uncertainty In Gis-Based Water Quality Modeling Of The Land Water Interface, Ahmad Mohamad Salah Feb 2009

Stochastic Spatio-Temporal Uncertainty In Gis-Based Water Quality Modeling Of The Land Water Interface, Ahmad Mohamad Salah

Theses and Dissertations

Integrated water resources management has been used for decades in various formats. The limited resources and the ever growing population keep imposing pressure on decision makers to better-, and reliably, manage the available waters. On the other hand, the continuous development in computing and modeling power has helped modelers and decision makers considerably. To use these models, assumptions have to be made to fill in the gaps of missing data and to approximate the current conditions. The type and amount of information available can also be used to help select the best model from the currently available models. Advances in …