Digital Commons Network^™

A Study Of Wavelet-Based Noise Reduction Techniques In Mammograms, Varun Shah

Masters Theses

"Breast cancer is one of the most common cancers and claims over one thousand lives every day. Breast cancer turns fatal only when diagnosed in late stages, but can be cured when diagnosed in its early stages. Over the last two decades, Digital Mammography has served the diagnosis of breast cancer. It is a very powerful aid for early detection of breast cancer. However, the images produced by mammography typically contain a great amount noise from the inherent characteristics of the imaging system and the radiation involved. Shot noise or quantum noise is the most significant noise which emerges as …

Optimization Of Process Planning For Focused Ion Beam Machine In Nano-Manufacturing, Sushrut Shekhar Naik

Masters Theses

"The current revolution witnessed by nanotechnology is facing several challenges such as manufacturing of nano sized devices economically on a large scale. Focused ion beam (FIB) technology is one of the widely used approaches for nano-manufacturing due to its versatile nature. It provides accurate machining and process repeatability and has a range of applications. Major challenges for the current FIB process are the tradeoffs between quality, the processing time, and the long planning time. This research provides a pathway to eliminate the current problems facing nanotechnology. Using MATLAB and the Helios 600 FIB/SEM instrument available, modeling and analyses are carried …

Effects Of Coal Comminution In Relation To Waterjet And Selected Feed Properties, Yaqing Li

Masters Theses

"The necessity to develop a viable alternative to oil means that the development of coal-water fuels (CWF) has become increasingly important. However, the existing methods of comminution to prepare ultrafine particles for CWF are very inefficient. Consequently, a number of novel methods of comminution have been investigated in order to increase the efficiency of the process.

In this research, a new method of comminution using a high-pressure waterjet has been tested to produce ultrafine particle sizes necessary for efficient CWF process. To establish the fundamental performance of the waterjet mill, the influence of the operational pressure, standoff distance, feed size, …

Direct Shear Testing Of Fractured Rocks From Missouri Used To Evaluate Potential Fault Reactivation Induced By Carbon Dioxide Sequestration, Ishan Kumar

Masters Theses

"Geological storage projects of CO₂ are designed to maintain secure storage for thousands of years. Carbon Capture and Storage has been identified as one of the methods which is used to reduce global emission of CO₂ and achieve lower concentration of CO₂ in the atmosphere by capturing the CO₂ from the flue gases and storing it in underground formations. Potential leakage of injected CO₂ from the reservoir to the surface is caused by the reactivation of pre-existing faults and fractures which is caused by the change in the state of stresses and the pore pressure. To avoid damage to the …

Sputter Deposition Of Thin-Film Capacitors Onto Low Temperature Co-Fired Ceramic Substrates, Jack Murray

Masters Theses

"Single layer thin film capacitor structures were fabricated on the surface of low temperature co-fired ceramic (LTCC) substrates using sputter deposition. The capacitor structures had areas between ~10⁴ µm² to ~10⁶ µm² and featured ~200 nm Al or Pt electrodes with 150-1500 nm Al₂O₃ dielectric layers. Impedance analysis and current-voltage testing were carried out to determine the effect of electrode material and dielectric thickness upon capacitor performance. Capacitance values for devices with Al electrodes ranged from ~10 to ~700 pF, depending on capacitor area and dielectric thickness, and the fit to expected values was better than devices with Pt or …

3d Spatio-Temporal Analysis For Compressive Sensing In Magnetic Resonance Imaging Of The Murine Cardiac Cycle, Brice Aaron Hirst

Masters Theses

"This thesis consists of two major contributions, each of which has been prepared in a conference paper. These papers will be submitted for publication in the SPIE 2013 Medical Imaging Conference and the ASEE 2013 Annual Conference.

The first paper explores a three-dimensional compressive sensing (CS) technique for reducing measurement time in MR imaging of the murine (mouse) cardiac cycle. By randomly undersampling a single 2D slice of a mouse heart at regular time intervals as it expands and contracts through the stages of a heartbeat, a CS reconstruction algorithm can be made to exploit transform sparsity in time as …

Cooperative Power Control Approaches Towards Fair Radio Resource Allocation For Wireless Network, Liuju Wu

Masters Theses

"Performance optimization in wireless networks is a complex problem due to variability and dynamics in network topology and density, traffic patterns, mutual interference, channel uncertainties, etc. Opportunistic or selfish approaches may result in unbalanced allocation of channel capacity where particular links are overshadowed. This degrades overall network fairness and hinders a multi-hop communication by creating bottlenecks. A desired approach should allocate channel capacity proportionally to traffic priority in a cooperative manner. This work consists of two chapters that address the fairness share problem in wireless ad hoc, peer-to-peer networks and resource allocation within Cognitive Radio network. In the first paper, …

Fabrication Of Complex Ceramic Parts With Sacrificial Material Using Freeze-Form Extrusion Fabrication, Diego Armando Garcia MontañO

Masters Theses

"An additive manufacturing process called Freeze-form Extrusion Fabrication (FEF) was developed in this study to fabricate complex ceramic parts that require the use of sacrificial materials. The aqueous paste of alumina (Al₂O₃) was used as the main material, with solids loadings as high as 50 vol. % and water as the main liquid medium. Methyl cellulose, with a 10 vol. % solids loading and 90 vol. % water content, was used as the sacrificial material. The freeze-form extrusion machine has multiple extruders (extrusion devices) capable of fabricating parts from multiple materials without mixing them. The dynamic process of extruding alumina …

Using Lidar As A Monitoring Device To Calculate Volume Of Rockfall Over Time, Travis James Kassebaum

Masters Theses

"There are many natural hazards which threaten the stability of highway infrastructure and the safety of motoring public. Rockfall and unstable slopes are one of the major concerns. This thesis describes a method which safely and accurately evaluates rockfall on rock outcrops through the use of Light Detection and Ranging (LiDAR) data. LiDAR is an imaging technology which can be used to measure and evaluate possible rock outcrop hazards such as: rockfall, rock-avalanches, debris flows, and landslides. LiDAR produces a three dimensional point cloud of millions of points which gives spatial data on the scanned object, accurate to millimeters, in …

Parametric Moment Closure For Non-Linear State Dependent Stochastic Systems, Ritesh Arora

Masters Theses

"This research highlights the use of moment closure approximation techniques to provide analytical approximations to nonlinear state dependent systems. Nonlinear systems are often difficult to solve and often approximated through the use of simulation. However, Moment Closure has the capability to derive an approximate solution by making a closed form solution out of open set of differential equations representing nonlinear system behavior in both transient and equilibrium state. It is this capability of approximating the closed form solution to complex systems that draws interest in the use of this method within systems engineering. This research further extends to the stability …

Generic Kinematic Simulation For Verification Of Laser Deposition Tool Paths, Sweta Dhaveji Chakravadhanula

Masters Theses

"The development of 3D visual simulation tool for machine simulation is a key approach in saving time and reducing cost. It is an important step before a manufacturing operation is performed on a part, as a tool to detect collision and validate the operation results. There are several kinds of manufacturing equipment being used and hence there is a need for the development of a generalized method to visually simulate a variety of machines. This paper presents the research conducted on describing machine configuration in a generic format which not only gives useful information, but can also be used as …

A Feasibility Analysis Of Retrofitting Existing Roadway Lighting Infrastructure With Led Technology, Sean Michael Schmidt

Masters Theses

LED technology has advanced towards use in high intensity lighting purposes. LED luminaires have a significantly longer expected lifetime than traditional high-intensity discharge lighting systems. Due to these recent improvements in LED technology, there is a growing need for a comprehensive method to analyze the applicability of LED luminaires for use on major routes and roadways. This research investigates the acceptability of LED luminaires for use on major roadways through a feasibility analysis using data collected at various LED street light testing sites. Nine distinct LED luminaires were analyzed in field testing. The field data was then analyzed and compared …

Effects Of High Volume Fly Ash And Powder Activators On Plastic And Hardened Concrete Properties, Drew Alexander Davis

Masters Theses

This study was performed to examine the effects of high volumes of Class C fly ash modified by powder activators upon the plastic and hardened properties of concrete. In a companion study, five Missouri area cements and five Class C fly ashes were examined for incompatibilities, with the most and least reactive combinations being scaled up to full scale concrete testing. Two baseline concrete mixtures were examined, the only difference in mixtures being the sources of portland cement and fly ash. Fly ash replacement was examined at 50% and 70% replacement (by total cementitious mass). Three powder activators were used …

A Modified Fixed Sphere Decoding Algorithm For Under-Determined Mimo Systems, Chen Qian, Jingxian Wu, Yahong Rosa Zheng, Zhaocheng Wang

Electrical and Computer Engineering Faculty Research & Creative Works

A modified FSD algorithm is proposed for under-determined (UD) multiple-input multiple-output (MIMO) systems with N transmit antennas and M < N receive antennas. This paper focuses on the low-complexity detection of coded UD-MIMO systems with iterative turbo detection, where a soft-input soft-output (SISO) MIMO detector exchanges soft information with a SISO decoder. in the first iteration, a modified fixed complexity sphere decoding (FSD) method is developed by utilizing the structure of a UD-MIMO system. the modified FSD employs a new detection ordering scheme that has a lower complexity but a better performance compared to the conventional ordering scheme. from the second iteration and beyond, the MIMO detector is implemented with a generalized serial interference cancelation (GSIC) scheme and a block decision feedback equalizer (BDFE) to further reduce the complexity. Simulation results show that the newly proposed FSD-GSIC-BDFE structure can achieve significant performance gains over existing schemes, especially for systems with high level modulations. © 2012 IEEE.

Graphical Image Classification Combining An Evolutionary Algorithm And Binary Particle Swarm Optimization, Beibei Cheng, Renzhong Wang, Sameer K. Antani, R. Joe Stanley, George R. Thoma

Electrical and Computer Engineering Faculty Research & Creative Works

Biomedical journal articles contain a variety of image types that can be broadly classified into two categories: regular images, and graphical images. Graphical images can be further classified into four classes: diagrams, statistical figures, flow charts, and tables. Automatic figure type identification is an important step toward improved multimodal (text + image) information retrieval and clinical decision support applications. This paper describes a feature-based learning approach to automatically identify these four graphical figure types. We apply Evolutionary Algorithm (EA), Binary Particle Swarm Optimization (BPSO) and a hybrid of EA and BPSO (EABPSO) methods to select an optimal subset of extracted …

Scholars' Mine Annual Statistics Report For Jan. 1 2011 - Dec. 31 2011, Library And Learning Resources

Scholars’ Mine Statistics

No abstract provided.

Agent-Based Model Of Aerial Ad-Hoc Network Market Potential, Christopher B. Watkins, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Mobile Ad hoc NETworks (MANETs) have seen significant growth as a research topic in recent years. as opposed to a traditional network with a fixed node infrastructure, the nodes in a MANET are free to move and arbitrarily organize themselves while maintaining wireless communication with each other. the major benefit of MANETs is the lack of reliance on a fixed network infrastructure. the challenge is to dynamically route traffic through a set of mobile network nodes. MANETs represent a novel solution for providing internet access in aircraft. Currently, each aircraft maintains its own gateway to the internet using expensive satellite …

Interstaple Dithiol Cross-Linking In Au 25(Sr) 18 Nanomolecules: A Combined Mass Spectrometric And Computational Study, Vijay Reddy Jupally, Rajesh Kota, Eric Van Dornshuld, Daniell L. Mattern, Gregory S. Tschumper, De En Jiang, Amala Dass

Chemistry Faculty Research & Creative Works

A systematic study of cross-linking chemistry of the Au 25(SR) 18 nanomolecule by dithiols of varying chain length, HS-(CH₂)_n-SH where n = 2, 3, 4, 5, and 6, is presented here. Monothiolated Au₂₅ has six [RSAuSRAuSR] staple motifs on its surface, and MALDI mass spectrometry data of the ligand exchanged clusters show that propane (C3) and butane (C4) dithiols have ideal chain lengths for interstaple cross-linking and that up to six C3 or C4 dithiols can be facilely exchanged onto the cluster surface. Propanedithiol predominately exchanges with two monothiols at a time, making cross-linking bridges, …

Highly Sensitive Refractive Index Optical Fiber Sensors Fabricated By A Femtosecond Laser, Jinpeng Yang, Lan Jiang, Sumei Wang, Qianghua Chen, Benye Li, Hai Xiao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Highly sensitive and robust refractive index (RI) fiber sensors are proposed, which are based on concatenating two micro air-cavities. the micro air-cavities embedded in the fiber along the core axis are fabricated by combining the techniques of femtosecond laser micromachining and arc fusion splicing. the full width at half-maximum (FWHM) of an attenuation peak of a sensor in air is 0.048 nm, and the extinction ratio is ∼15 dB. When the diameter of the cavity is slightly larger than the fiber core diameter, the sensor is highly sensitive to external RI changes. a high sensitivity of 172.4 nm/refractive index unit …

Roman: Routing And Opportunistic Management Of Airborne Networks, Hemanth Meka, Lekshmi Manian Chidambaram, Sanjay K. Madria, Mark Linderman, Mohan Kumar, Sharma Chakravarthy

Computer Science Faculty Research & Creative Works

Most of the routing and replication algorithms for Mobile Peer to Peer (M-P2P) networks assume the network to be large and therefore, the architecture and algorithms are designed to be scalable. These algorithms however may not perform well with limited number of nodes in a network such as of UAVs. Thus, it is better to design algorithms to increase the efficiency of a small network if scalability is no longer an issue. for such small networks, we design and simulate an effective two layered graph-based routing algorithm using store/forward concept. We also take into account UAVs orientation and configuration of …

Empirical Study Of An Intelligent Argumentation System In Mcdm, Xiaoqing Liu, Rubal Wanchoo, Ravi Santosh Arvapally

Computer Science Faculty Research & Creative Works

Intelligent argumentation based collaborative decision-making system assists stakeholders in a decision-making group to assess various alternatives under different criterion based on the argumentation. a performance score of each alternative under every criterion in Multi-Criteria Decision Making (MCDM) is represented in a decision matrix and it denotes satisfaction of the criteria by that alternative. the process of determining the performance scores of alternatives in a decision matrix for criterion could be controversial sometimes because of the subjective nature of criterion. We developed a framework for acquiring performance scores in a decision matrix for multi-criteria decision making using an intelligent argumentation and …

Effect Of Thin Film Confined Between Two Dissimilar Solids On Interfacial Thermal Resistance, Zhi Liang, Hai-Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A Non-Equilibrium Molecular Dynamics Model is Developed to Investigate How a Thin Film Confined between Two Dissimilar Solids Affects the Thermal Transport Across the Material Interface. for Two Highly Dissimilar (Phonon Frequency Mismatched) Solids, It is Found that the Insertion of a Thin Film between Them Can Greatly Enhance Thermal Transport Across the Material Interface by a Factor of 2.3 If the Thin Film Has One of the Following Characteristics: (1)a Multi-Atom-Thick Thin Film of Which the Phonon Density of States (DOS) Bridges the Two Different Phonon DOSs for the Solid on Each Side of the Thin Film; (2)a Single-Atom-Thick …

Structures, Energetics And Vibrational Frequency Shifts Of Hydrated Pyrimidine, J. Coleman Howard, Nathan I. Hammer, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

More than 70 unique micro-hydrated structures of pyrimidine, ranging in size from 1 to 7 water molecules, have been characterized with the B3LYP density functional and the 6-311++G(2df,2pd) triple-ζ split-valence basis set. Explicitly correlated MP2-F12 single-point computations were performed on each structure with a correlation consistent triple-ζ basis set to estimate the relative and dissociation energies at the MP2 complete basis set (CBS) limit. Many of these new structures have significantly lower energies than those previously reported (by as much as 12.66 kcal mol-1). For clusters with 1 and 2 water molecules, the MP2-F12 relative and dissociation energies are virtually …

Intelligent Methods For Smart Microgrids, Joydeep Mitra, Niannian Cai, Mo Yuen Chow, Sukumar Kamalasadan, Wenxin Liu, Wei Qiao, Sri Niwas Singh, Anurag K. Srivastava, Sanjeev K. Srivastava, Ganesh K. Venayagamoorthy, Ziang Zhang

Electrical and Computer Engineering Faculty Research & Creative Works

This paper summarizes ongoing research in the application of intelligent methods to the design, modeling, simulation and control of microgrids including optimal design of microgrids, and centralized and decentralized control. © 2011 IEEE.

On-Line Voltage Stability Load Index Estimation Based On Pmu Measurements, K. Joseph Makasa, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

A new method for estimation of Voltage Stability Load Index (VSLI) for a power system using data from optimally located phasor measurement units (PMU) is presented in this paper. Optimal PMU placement was carried out considering islanding operating conditions. vs.LI is estimated using a kind of recurrent neural network known as the Echo State Network (ESN). the development ESN is computational efficient and provides accurate estimation. Results of optimal PMU placement for normal and islanded operating conditions, and ESN estimation of vs.LI on the IEEE 14 bus system is presented. © 2011 IEEE.

Should Distribution Systems Engineering Be Taught At The Undergraduate Level?, Badrul Chowdhury, Anil Pahwa

Electrical and Computer Engineering Faculty Research & Creative Works

Although there are some exceptions, a distribution systems course is not part of a typical undergraduate curriculum. the course is usually taught at the graduate level. Teaching a distribution systems course requires the student to have a background in balanced three-phase power system modeling such as that obtained from a first power systems analysis course. the requirement to add breadth to an undergraduate curriculum often precludes the notion of depth in any one area unless a student takes the depth courses as technical or free electives. an argument could be made that a distribution systems course does not contain much …

Innovative Smart Grid Control Technologies, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The smart electric power grid will evolve into a very complex adaptive system under semi-autonomous distributed control. It will be spatially and temporally complex, non-convex, non-linear and non-stationary, with lots of variability and uncertainties beyond what the traditional power system experiences today. the distributed integration of intermittent sources of energy and energy storage to a power grid further adds complexity and challenges to modeling, control and optimization of the grid. Innovative control technologies are needed to handle the growing complexity of a smart grid, maximize the penetration of renewable energy, and provide maximum utilization of available energy storage, especially plug-in …

Intelligent Sense-Making For Smart Grid Stability, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The power systems of the future - smart grids - will see an increase in both renewable energy sources and load demand, thus increasing the need for fast dynamic reconfiguration of system parameters to handle energy and load dispatches. Power systems will need to be monitored continuously to maintain stability under normal and abnormal operating conditions and when facing disturbances. a combination of system state prediction, dynamic power flow, system optimization, and solution stability checking will allow for a more reliable, affordable, efficient and clean power grid. the optimization and control systems on a smart grid will require a computational …

Risk Assessment Of Cascading Outages: Part I - Overview Of Methodologies, Marianna Vaiman, Keith Bell, Yousu Chen, Badrul H. Chowdhury, Ian Dobson, Paul Hines, Milorad Papic, Stephen S. Miller, Pei Zhang

Electrical and Computer Engineering Faculty Research & Creative Works

This paper is a result of ongoing activity carried out by Understanding, Prediction, Mitigation and Restoration of Cascading Failures Task Force under IEEE Computer Analytical Methods Subcommittee (CAMS). the task force's previous papers are focused on general aspects of cascading outages such as understanding, prediction, prevention and restoration from cascading failures. This is the first of two new papers, which extend this previous work to summarize the state of the art in cascading failure risk analysis methodologies and modeling tools. This paper is intended to be a reference document to summarize the state of the art in the methodologies for …

Computational Intelligence For Control Of Wind Turbine Generators, Wei Qiao, Jiaqi Liang, Ganesh K. Venayagamoorthy, Ronald Harley

Electrical and Computer Engineering Faculty Research & Creative Works

This paper summarizes past and ongoing research in the area of the application of computational intelligence (CI) for control of wind turbine generators (WTGs). Several intelligent design approaches and control strategies, including optimal design of WTG controllers using particle swarm optimization (PSO) and mean-variance optimization (MVO) algorithms and adaptive critic design-Based coordinated optimal adaptive control for wind plants and shunt FACTS devices, are presented for dynamic performance and fault ride-through enhancement of WTGs and the associated power grid. the effectiveness of these intelligent design approaches and control strategies are demonstrated by nonreal- and real-time simulations in PSCAD/EMTDC and RSCAD/RTDS, respectively. …