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A Novel Injectable Borate Bioactive Glass Cement As An Antibiotic Delivery Vehicle For Treating Osteomyelitis, Hao Ding, Cunju Zhao, Xu Cui, Yifei Gu, Weitao Jia, M. N. Rahaman, Yang Wang, Wenhai Huang, Changqing Zhang Jan 2014

A Novel Injectable Borate Bioactive Glass Cement As An Antibiotic Delivery Vehicle For Treating Osteomyelitis, Hao Ding, Cunju Zhao, Xu Cui, Yifei Gu, Weitao Jia, M. N. Rahaman, Yang Wang, Wenhai Huang, Changqing Zhang

Materials Science and Engineering Faculty Research & Creative Works

Background: A novel injectable cement composed of chitosan-bonded borate bioactive glass (BG) particles was evaluated as a carrier for local delivery of vancomycin in the treatment of osteomyelitis in a rabbit tibial model. Materials and Methods: The setting time, injectability, and compressive strength of the borate BG cement, and the release profile of vancomycin from the cement were measured in vitro. The capacity of the vancomycin-loaded BG cement to eradicate methicillin-resistant Staphylococcus aureus (MRSA)-induced osteomyelitis in rabbit tibiae in vivo was evaluated and compared with that for a vancomycin-loaded calcium sulfate (CS) cement and for intravenous injection of vancomycin. Results: …


Innovative Rts Technology For Dry Beneficiation Of Phosphate, Ahmed Sobhy, Daniel Tao Jan 2014

Innovative Rts Technology For Dry Beneficiation Of Phosphate, Ahmed Sobhy, Daniel Tao

Mining Engineering Faculty Research & Creative Works

The Crago double flotation process is widely used for upgrading raw phosphate in Florida. However, it is a water-based physicochemical process and consumes a huge amount of water and chemicals and is not efficient to remove dolomite from phosphate. In addition, the final phosphate flotation concentrate often has a grade of 30-31% P2O5, which is below the BPL content of 75% (or 34.3% P2O5) required for making the animal feed grade phosphate. This study is performed to evaluate the potential and feasibility of the innovative rotary triboelectrostatic separator (RTS) as a dry phosphate beneficiation process. The RTS technology is characterized …


Study On Surface Permeability Of Concrete Under Immersion, Jun Liu, Feng Xing, Biqin Dong, Hongyan Ma, Dong Pan Jan 2014

Study On Surface Permeability Of Concrete Under Immersion, Jun Liu, Feng Xing, Biqin Dong, Hongyan Ma, Dong Pan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this paper, concrete specimens are immersed in ultrapure water, to study the evolutions of surface permeability, pore structure and paste microstructure following the prolonging of immersion period. According to the results, after 30-day immersion, the surface permeability of concrete becomes higher as compared with the value before immersion. However, further immersion makes the surface permeability decrease, so that the value measured after 150-day immersion is only half that measured after 30-day immersion. The early increase in surface permeability should be mainly attributed to the leaching of calcium hydroxide, while the later decrease to the refinement of pore structure due …


Development And Application Of Improved Shotctrete Refractory For Aluminum Rotary Furnace Applications, James G. Hemrick, Angela Rodrigues-Schroer, Dominick Colavito, Jeffrey D. Smith, Kelley O'Hara Jan 2014

Development And Application Of Improved Shotctrete Refractory For Aluminum Rotary Furnace Applications, James G. Hemrick, Angela Rodrigues-Schroer, Dominick Colavito, Jeffrey D. Smith, Kelley O'Hara

Materials Science and Engineering Faculty Research & Creative Works

Oak Ridge National Laboratory, in collaboration with refractory manufacturer Minteq International, Inc., academic partner Missouri University of Science and Technology and refractory end users have developed novel refractory systems and techniques to reduce energy consumption of refractory lined vessels. The objective of this U.S. DOE funded project was to address the need for innovative refractory compositions by developing novel gunnable refractory compositions for use in high temperature and high alkali environments. Developed materials utilized new aggregate materials, bond systems, protective coatings, and phase formation techniques. Under this project, materials were developed specifically for aluminum rotary dross furnace applications and a …


Timekeeping Issues In Ultra-Quality Metering Systems, David D. Haynes, Steven M. Corns Jan 2014

Timekeeping Issues In Ultra-Quality Metering Systems, David D. Haynes, Steven M. Corns

Engineering Management and Systems Engineering Faculty Research & Creative Works

The improvements made to smart metering systems in terms of performance and accuracy have in many cases created a gap in the requirements for timekeeping performance. When clock errors accumulate in different metrology systems, data collected from one system cannot be compared to data collected from another system. This paper recommends the use of a common time base for all data gathering systems, and that systems clocks are corrected with numerous minor corrections when possible, rather than major corrections. © 2013 IEEE.


Safety Effect Of Missouri's Strategic Highway Safety Plan: Missouri's Blueprint For Safer Roadways, Mojtaba A. Mohammadi, V. A. Samaranayake, Ghulam H. Bham Jan 2014

Safety Effect Of Missouri's Strategic Highway Safety Plan: Missouri's Blueprint For Safer Roadways, Mojtaba A. Mohammadi, V. A. Samaranayake, Ghulam H. Bham

Mathematics and Statistics Faculty Research & Creative Works

This study systematically evaluated the changes in motor vehicle crashes that occurred on the Missouri Interstate highway system following the implementation of the Missouri Strategic Highway Safety Plan (MSHSP) between 2004 and 2007. The MSHSP implemented crash injury reduction strategies in enforcement, education, engineering, and public policy. Empirical Bayesian methods were commonly used to evaluate the effects of any change in safety as a result of countermeasures. This paper presents a simple new approach to evaluating the effects of Missouri's safety plans on roadway crashes. For crash data associated with traffic and roadway characteristics, negative binomial regression models were developed …


Foundations Of Coverage Algorithms In Autonomic Mobile Sensor Networks, Mark Edward Snyder Jan 2014

Foundations Of Coverage Algorithms In Autonomic Mobile Sensor Networks, Mark Edward Snyder

Doctoral Dissertations

"Drones are poised to become a prominent focus of advances in the near future as hardware platforms manufactured via mass production become accessible to consumers in higher quantities at lower costs than ever before. As more ways to utilize such devices become more popular, algorithms for directing the activities of mobile sensors must expand in order to automate their work.

This work explores algorithms used to direct the behavior of networks of autonomous mobile sensors, and in particular how such networks can operate to achieve coverage of a field using mobility. We focus special attention to the way limited mobility …


Fast Feature Selection In A Gpu Cluster Using The Delta Test, Alberto Guillén, M. Isabel García Arenas, Mark Van Heeswijk, Dusan Sovilj, Amaury Lendasse, Luis Javier Herrera, Héctor Pomares, Ignacio Rojas Jan 2014

Fast Feature Selection In A Gpu Cluster Using The Delta Test, Alberto Guillén, M. Isabel García Arenas, Mark Van Heeswijk, Dusan Sovilj, Amaury Lendasse, Luis Javier Herrera, Héctor Pomares, Ignacio Rojas

Engineering Management and Systems Engineering Faculty Research & Creative Works

Feature or Variable Selection Still Remains an Unsolved Problem, Due to the Infeasible Evaluation of All the Solution Space. Several Algorithms based on Heuristics Have Been Proposed So Far with Successful Results. However, These Algorithms Were Not Designed for Considering Very Large Datasets, Making their Execution Impossible, Due to the Memory and Time Limitations. This Paper Presents an Implementation of a Genetic Algorithm that Has Been Parallelized using the Classical Island Approach, But Also Considering Graphic Processing Units to Speed Up the Computation of the Fitness Function. Special Attention Has Been Paid to the Population Evaluation, as Well as to …


Long-Term Time Series Prediction Using Op-Elm, Alexander Grigorievskiy, Yoan Miche, Anne Mari Ventelä, Eric Séverin, Amaury Lendasse Jan 2014

Long-Term Time Series Prediction Using Op-Elm, Alexander Grigorievskiy, Yoan Miche, Anne Mari Ventelä, Eric Séverin, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

In This Paper, an Optimally Pruned Extreme Learning Machine (Op-Elm) is Applied to the Problem of Long-Term Time Series Prediction. Three Known Strategies for the Long-Term Time Series Prediction I.e. Recursive, Direct and Dirrec Are Considered in Combination with Op-Elm and Compared with a Baseline Linear Least Squares Model and Least-Squares Support Vector Machines (Ls-Svm). among These Three Strategies Dirrec is the Most Time Consuming and its Usage with Nonlinear Models Like Ls-Svm, Where Several Hyperparameters Need to Be Adjusted, Leads to Relatively Heavy Computations. It is Shown that Op-Elm, Being Also a Nonlinear Model, Allows Reasonable Computational Time for …


Conquering Complexity: Challenges And Opportunities: Preface, Cihan H. Dagli Jan 2014

Conquering Complexity: Challenges And Opportunities: Preface, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

No abstract provided.


How To Rein In The Volatile Actor: A New Bounded Perspective, Abhijit Gosavi Jan 2014

How To Rein In The Volatile Actor: A New Bounded Perspective, Abhijit Gosavi

Engineering Management and Systems Engineering Faculty Research & Creative Works

Actor-critic algorithms are amongst the most well-studied reinforcement learning algorithms that can be used to solve Markov decision processes (MDPs) via simulation. Unfortunately, the parameters of the so-called "actor" in the classical actor-critic algorithm exhibit great volatility - getting unbounded in practice, whence they have to be artificially constrained to obtain solutions in practice. The algorithm is often used in conjunction with Boltzmann action selection, where one may have to use a temperature to get the algorithm to work, but the convergence of the algorithm has only been proved when the temperature equals 1. We propose a new actor-critic algorithm …


Carbon Constrained Integrated Inventory Control And Truckload Transportation With Heterogeneous Freight Trucks, Dinçer Konur Jan 2014

Carbon Constrained Integrated Inventory Control And Truckload Transportation With Heterogeneous Freight Trucks, Dinçer Konur

Engineering Management and Systems Engineering Faculty Research & Creative Works

This paper analyzes an integrated inventory control and transportation problem with environmental considerations. Particularly, explicit transportation modeling is included with inventory control decisions to capture per truck costs and per truck capacities. Furthermore, a carbon cap constraint on the total emissions is formulated by considering emission characteristics of various trucks that can be used for inbound transportation. Due to complexity of the resulting optimization problem, a heuristic search method is proposed based on the properties of the problem. Numerical studies illustrate the efficiency of the proposed method. Furthermore, numerical examples are presented to show that both costs and emissions can …


Study Of The Use Of A Genetic Algorithm To Improve Networked System-Of-Systems Resilience, Charles O. Adler, Cihan H. Dagli Jan 2014

Study Of The Use Of A Genetic Algorithm To Improve Networked System-Of-Systems Resilience, Charles O. Adler, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Large scale failures or degradation resulting from smaller initial failures or disruptions in networked system-of-systems are an issue in multiple areas - for example cascading failures in electrical power grids or large disruptions in national air traffic due to local or regional weather conditions. The system architecture can have a significant impact on system-of-systems susceptibility to large scale failures. The study presented in this paper uses a simple interdependent networked system-of-systems failure model, integrated into a unique objective function that addresses both the overall level of failure and the rate of failure progression, and a genetic algorithm to demonstrate an …


Computational Complexity Measures For Many-Objective Optimization Problems, David M. Curry, Cihan H. Dagli Jan 2014

Computational Complexity Measures For Many-Objective Optimization Problems, David M. Curry, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Multi-objective Optimization Problems (MOPs) are commonly encountered in the study and design of complex systems. Pareto dominance is the most common relationship used to compare solutions in MOPs, however as the number of objectives grows beyond three, Pareto dominance alone is no longer satisfactory. These problems are termed "Many-Objective Optimization Problems (MaOPs)". While most MaOP algorithms are modifications of common MOP algorithms, determining the impact on their computational complexity is difficult. This paper defines computational complexity measures for these algorithms and applies these measures to a Multi-Objective Evolutionary Algorithm (MOEA) and its MaOP counterpart.


On The Flexibility Of Systems In System Of Systems Architecting, Dincer Konur, Hadi Farhangi, Cihan H. Dagli Jan 2014

On The Flexibility Of Systems In System Of Systems Architecting, Dincer Konur, Hadi Farhangi, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

System of Systems (SoS) architecting requires analyzing a set of individual but interconnected systems simultaneously in order to build a communicating SoS, which can provide the capabilities needed. In general, the systems can provide a set of capabilities and the SoS architect needs to decide which systems to include in the SoS so that each capability is provided by at least one system. In this case, the systems are inflexible, i.e., a selected system will contribute to the SoS with all the capabilities it can provide. On the other hand, if SoS architect can incentivize systems to contribute specific capabilities …


A Hybrid Genetic Algorithm And Particle Swarm Optimization With Type-2 Fuzzy Sets For Generating Systems Of Systems Architectures, Siddhartha Agarwal, Louis E. Pape, Cihan H. Dagli Jan 2014

A Hybrid Genetic Algorithm And Particle Swarm Optimization With Type-2 Fuzzy Sets For Generating Systems Of Systems Architectures, Siddhartha Agarwal, Louis E. Pape, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Both modeling and simulating a system of systems (SoS) are difficult due not only to a changing environment but also the unique behavior that is linked to different participating systems. Generating architectures for a SoS is a multi-objective optimization problem with large number of variables and constraints. The paper presents several of computational intelligence techniques that can generate SoS architectures, such as genetic algorithms (GA), and particle swarm optimization (PSO) combined with Type 2 Fuzzy logic nets. The Maritime search and rescue (SAR) were used as a SoS domain scenario to both implement and demonstrate the architecting methodology. SAR utilizes …


A Static Voltage Security Region For Centralized Wind Power Integration-Part Ii: Applications, Tao Ding, Qinglai Guo, Rui Bo, Hongbin Sun, Boming Zhang, Tianen Huang Jan 2014

A Static Voltage Security Region For Centralized Wind Power Integration-Part Ii: Applications, Tao Ding, Qinglai Guo, Rui Bo, Hongbin Sun, Boming Zhang, Tianen Huang

Electrical and Computer Engineering Faculty Research & Creative Works

In Part I of this work, a static voltage security region was introduced to guarantee the safety of wind farm reactive power outputs under both base conditions and N-1 contingency. In this paper, a mathematical representation of the approximate N-1 security region has further studied to provide better coordination among wind farms and help prevent cascading tripping following a single wind farm trip. Besides, the influence of active power on the security region is studied. The proposed methods are demonstrated for N-1 contingency cases in a nine-bus system. The simulations verify that the N-1 security region is a small subset …


Phasor Measurement Unit Placement For Identifying Power Line Outages In Wide-Area Transmission System Monitoring, Hao Zhu, Yiyu Shi Jan 2014

Phasor Measurement Unit Placement For Identifying Power Line Outages In Wide-Area Transmission System Monitoring, Hao Zhu, Yiyu Shi

Electrical and Computer Engineering Faculty Research & Creative Works

Phasor measurement units (PMUs) are widely recognized to be instrumental for enhancing the power system situational awareness - a key step toward the future power grid. With limited PMU resources and high installation costs, it is of great importance to develop strategic PMU deployment methods. This paper focuses on optimally selecting PMU locations for monitoring transmission line status across the wide-area grid. To bypass the combinatorial search involved, a linear programming reformulation is first developed to provide an upper bound estimate for the global optimum. Furthermore, a greedy heuristic method is adopted with the complexity only linearly in the number …


Nonlinear Development And Secondary Instability Of Traveling Crossflow Vortices, Fei Li, Meelan M. Choudhari, Lian Duan, Chau-Lyan Chang Jan 2014

Nonlinear Development And Secondary Instability Of Traveling Crossflow Vortices, Fei Li, Meelan M. Choudhari, Lian Duan, Chau-Lyan Chang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Building upon the prior research targeting the laminar breakdown mechanisms associated with stationary crossflow instability over a swept-wing configuration, this paper investigates the secondary instability of traveling crossflow modes as an alternate scenario for transition. For the parameter range investigated herein, this alternate scenario is shown to be viable unless the initial amplitudes of the traveling crossflow instability are lower than those of the stationary modes by considerably more than one order of magnitude. The linear growth predictions based on the secondary instability theory are found to agree well with both parabolized stability equations and direct numerical simulation, and the …


Degradable Borate Glass Polyalkenoate Cements, L. Shen, A. Coughlan, Mark R. Towler, M. Hall Jan 2014

Degradable Borate Glass Polyalkenoate Cements, L. Shen, A. Coughlan, Mark R. Towler, M. Hall

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glass polyalkenoate cements (GPCs) containing aluminum-free borate glasses having the general composition Ag2O-Na2O-CaO-SrO-ZnO- TiO2-B2O3 were evaluated in this work. An initial screening study of sixteen compositions was used to identify regions of glass formation and cement compositions with promising rheological properties. The results of the screening study were used to develop four model borate glass compositions for further study. A second round of rheological experiments was used to identify a preferred GPC formulation for each model glass composition. The model borate glasses containing higher levels of TiO2 (7.5 mol %) …


A Protocol For Rheological Characterization Of Hydrogels For Tissue Engineering Strategies, Jonathan M. Zuidema, Christopher J. Rivet, Ryan J. Gilbert, Faith A. Morrison Jan 2014

A Protocol For Rheological Characterization Of Hydrogels For Tissue Engineering Strategies, Jonathan M. Zuidema, Christopher J. Rivet, Ryan J. Gilbert, Faith A. Morrison

Chemical and Biochemical Engineering Faculty Research & Creative Works

Hydrogels are studied extensively for many tissue engineering applications, and their mechanical properties influence both cellular and tissue compatibility. However, it is difficult to compare the mechanical properties of hydrogels between studies due to a lack of continuity between rheological protocols. This study outlines a straightforward protocol to accurately determine hydrogel equilibrium modulus and gelation time using a series of rheological tests. These protocols are applied to several hydrogel systems used within tissue engineering applications: agarose, collagen, fibrin, Matrigel™, and methylcellulose. The protocol is outlined in four steps: (1) Time sweeps to determine the gelation time of the hydrogel. (2) …


Position-Dependent Diffusion Of Light In Disordered Waveguides, Alexey Yamilov, Raktim Sarma, Brandon Redding, Ben Payne, Heeso Noh, Hui Cao Jan 2014

Position-Dependent Diffusion Of Light In Disordered Waveguides, Alexey Yamilov, Raktim Sarma, Brandon Redding, Ben Payne, Heeso Noh, Hui Cao

Physics Faculty Research & Creative Works

We present direct experimental evidence for position-dependent diffusion in open random media. The interference of light in time-reversed paths results in renormalization of the diffusion coefficient, which varies spatially. To probe the wave transport inside the system, we fabricate two-dimensional disordered waveguides and monitor the light intensity from the third dimension. Change the geometry of the system or dissipation limits the size of the loop trajectories, allowing us to control the renormalization of the diffusion coefficient. This work shows the possibility of manipulating wave diffusion via the interplay of localization and dissipation.


Behavior Of Hybrid Frp-Concrete-Steel Double-Skin Tubes Subjected To Cyclic Axial Compression, Omar I. Abdelkarim, Mohamed A. Elgawady Jan 2014

Behavior Of Hybrid Frp-Concrete-Steel Double-Skin Tubes Subjected To Cyclic Axial Compression, Omar I. Abdelkarim, Mohamed A. Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents the results of an experimental study that was conducted to investigate the effects of key parameters on the compressive behavior of fiber-reinforced polymer (FRP)-concrete-steel double-skin tubular columns (FSDT). Hybrid FSDT columns have been introduced as a new form of hybrid columns. They consist of an outer tube made of FRP and inner tub made of steel, with sandwiched concrete between them. This paper investigated the effect of fiber angle and the ratio of steel tube diameter to its thickness (Di/ts) on the compressive behavior of FSDT columns. Six FSDT cylinders with different (Di/ts), in addition to two …


Electromagnetic Cell With Three-Dimensional Polarization Dynamic Control, Bo O. Zhu, Weng Cho Chew, Lijun Jiang Jan 2014

Electromagnetic Cell With Three-Dimensional Polarization Dynamic Control, Bo O. Zhu, Weng Cho Chew, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

An electromagnetic (EM) cell is demonstrated to create the uniform electric field with 3-D polarization dynamic control for the EM compatibility/ interference (EMC/EMI) testing. We utilize 3-D orthogonal slotline structures to build the walls of the EM cell and produce uniform electric field inside the cell by feeding the slotlines in phase and terminating them with matching loads. The uniform electric field is similar to a standing wave produced by the slotline modes propagating in opposite directions. Microwave switches are integrated into the slotlines so that we can choose the operating slotline dynamically and change its orientation in a 3-D …


Critical Path Monitor Enabled Dynamic Voltage Scaling For Graceful Degradation In Sub-Threshold Designs, Yu Guang Chen, Tao Wang, Kuan Yu Lai, Wan Yu Wen, Yiyu Shi Jan 2014

Critical Path Monitor Enabled Dynamic Voltage Scaling For Graceful Degradation In Sub-Threshold Designs, Yu Guang Chen, Tao Wang, Kuan Yu Lai, Wan Yu Wen, Yiyu Shi

Electrical and Computer Engineering Faculty Research & Creative Works

Sub-threshold designs play an important role in energy constrained applications. In those designs, path delays depend exponentially on threshold voltage/temperature. As such, dynamic configurations at runtime are desired for best trade-off between operating power and performance. Unfortunately, most existing works only consider either process or temperature variations but not both, resulting in sub-optimal configurations or even functional failures. Moreover, little study has been performed on the graceful degradation of sub-threshold designs, which is important in the presence of drastic delay variations. Towards this, we present a novel critical path monitor based dynamic voltage scaling scheme. Considering both process and temperature …


Numerical Analysis Of Thermal Stress And Deformation In Multi-Layer Laser Metal Deposition Process, Heng Liu Jan 2014

Numerical Analysis Of Thermal Stress And Deformation In Multi-Layer Laser Metal Deposition Process, Heng Liu

Masters Theses

"Direct metal deposition (DMD) has gained increasing attention in the area of rapid manufacturing and repair. It has demonstrated the ability to produce fully dense metal parts with complex internal structures that could not be achieved by traditional manufacturing methods. However, this process involves extremely high thermal gradients and heating and cooling rates, resulting in residual stresses and distortion, which may greatly affect the product integrity. The purpose of this thesis is to study the features of thermal stress and deformation involved in the DMD process. Utilizing commercial finite element analysis (FEA) software ABAQUS, a 3-D, sequentially coupled, thermo-mechanical model …


Data Classification And Forecasting Using The Mahalanobis-Taguchi Method, Adebolaji A. Jobi-Taiwo Jan 2014

Data Classification And Forecasting Using The Mahalanobis-Taguchi Method, Adebolaji A. Jobi-Taiwo

Masters Theses

"Classification and forecasting are useful concepts in the field of condition monitoring. Condition monitoring refers to the analysis and monitoring of system characteristics to understand and identify deviations from normal operating conditions. This can be performed for prediction, diagnosis, or prognosis or a combination of any these purposes. Fault identification and diagnosis are usually achieved through data classification, while forecasting methods are usually used to accomplish the prediction objective. Data gathered from monitoring systems often consists of multiple multivariate time series and is fed into a model for data analysis using various techniques. One of the data analysis techniques used …


Numerical Simulations For Wellbore Stability And Integrity For Drilling And Completions, Nevan Christopher Himmelberg Jan 2014

Numerical Simulations For Wellbore Stability And Integrity For Drilling And Completions, Nevan Christopher Himmelberg

Masters Theses

"Conventional wellbore trajectory planning is commonly based on an Andersonian state of stress [SoS] and the optimum well azimuth and inclination for a specific depth can be determined using stereographic projections of the safe mud weight window. In this thesis a new methodology using the complete stress tensor is developed to determine optimal well trajectories for complex in-situ stress scenarios. This study uses a 3D finite element analysis to simulate the SoS based on an integrated 3D MEM. The model yields the complete stress tensor at every location for a planned future well path. Using standard equations to determine the …


Updated Screening Criteria For Steam Flooding Based On Oil Field Projects Data, Mariwan Qadir Hama Jan 2014

Updated Screening Criteria For Steam Flooding Based On Oil Field Projects Data, Mariwan Qadir Hama

Masters Theses

"Enhanced oil recovery (EOR) screening is considered the first step in evaluating potential EOR techniques for candidate reservoirs. Therefore, as new technologies are developed, it is important to update the screening criteria. Many of the screening criteria for steam flooding that have been described in the literature were based on data collected from EOR surveys biennially published in the Oil & Gas Journal. However, these datasets contain some problems, including outliers, missing data, inconsistent data and duplicate data, that could affect the accuracy of the results. Despite the importance of ensuring the quality of a dataset before running analyses, data …


Modelling Of Directed Energy Deposition Processes, Xueyang Chen Jan 2014

Modelling Of Directed Energy Deposition Processes, Xueyang Chen

Masters Theses

"The laser additive manufacturing technique of laser deposition allows quick fabrication of fully-dense metallic components directly from Computer Aided Design (CAD) solid models. The applications of laser deposition include rapid prototyping, rapid tooling and part refurbishment. The development of an accurate predictive model for laser deposition is extremely complicated due to the multitude of process parameters and materials properties involved. In this work, a heat transfer and fluid flow model is developed.

In the heat transfer and fluid flow model, the governing equations for solid, liquid and gas phases in the calculation domain have been formulated using the continuum model. …