Engineering Commons^™

Synthesis And Characterization Of A Novel Amphiphilic Core-Corona Hyperbranched Polymer, Composed Of Ehmo And Ehmopeg, For Drug Delivery., Khushboo Sharma

Theses and Dissertations

A novel amphiphilic core-corona hyperbranched polymer, composed of 3-ethyl-3-(hydroxylmethyl) oxetane (EHMO) and PEGylated EHMO (EHMOPEG), was synthesized through cationic ring opening polymerization. Nuclear Magnetic Resonance spectroscopy (NMR), Dynamic Light Scattering (DLS), and Fourier Transform Infrared spectroscopy (FTIR) were used to characterize the polymer structure and degree of branching. It was found that the degree of branching (DOB) of the polymer was affected by the weight % ratios of EHMO/EHMOPEG used in polymerization. As the weight % ratio of EHMO/ EHMOPEG decreased, the DOB was observed to increase. Polymeric particles based on the synthesized polymer were prepared using the O/W (Oil …

Preparation Of Coated Microtools For Electrochemical Machining Applications, Ajaya K. Swain

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

PREPARATION OF COATED MICROTOOLS FOR ELECTROCHEMICAL MACHINING APPLICATIONS

Ajaya K. Swain, M.S. University of Nebraska, 2010

Advisor: K.P. Rajurkar

Coated tools have improved the performance of both traditional and nontraditional machining processes and have resulted in higher material removal, better surface finish, and increased wear resistance. However, a study on the performance of coated tools in micromachining has not yet been adequately conducted. One possible reason is the difficulties associated with the preparation of coated microtools. Besides the technical requirement, economic and environmental aspects of the material and the coating technique used also play a significant role in coating microtools. …

Current Density And Continuity In Discretized Models, Timothy B. Boykin, Mathieu Luisier, Gerhard Klimeck

Birck and NCN Publications

Discrete approaches have long been used in numerical modelling of physical systems in both research and teaching. Discrete versions of the Schr ¨ odinger equation employing either one or several basis functions per mesh point are often used by senior undergraduates and beginning graduate students in computational physics projects. In studying discrete models, students can encounter conceptual difficulties with the representation of the current and its divergence because different finite-difference expressions, all of which reduce to the current density in the continuous limit, measure different physical quantities. Understanding these different discrete currents is essential and requires a careful analysis of …

Elements Of Study On Dynamic Materials, Marine Rousseau, Gerard A. Maugin, Mihhail Berezovski

Publications

As a preliminary study to more complex situations of interest in small-scale technology, this paper envisages the elementary propagation properties of elastic waves in one-spatial dimension when some of the properties (mass density, elasticity) may vary suddenly in space or in time, the second case being of course more original. Combination of the two may be of even greater interest. Toward this goal, a critical examination of what happens to solutions at the crossing of pure space-like and time-like material discontinuities is given together with simple solutions for smooth transitions and numerical simulations in the discontinuous case. The effects on …

Cyber-Physical Codesign Of Distributed Structural Health Monitoring With Wireless Sensor Networks, Gregory Hackmann, Weijun Guo, Guirong Yan, Chenyang Lu, Shirley Dyke

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Our Deteriorating Civil Infrastructure Faces the Critical Challenge of Long-Term Structural Health Monitoring for Damage Detection and Localization. in Contrast to Existing Research that Often Separates the Designs of Wireless Sensor Networks and Structural Engineering Algorithms, This Paper Proposes a Cyber-Physical Co-Design Approach to Structural Health Monitoring based on Wireless Sensor Networks. Our Approach Closely Integrates (1) Flexibility-Based Damage Localization Methods that Allow a Tradeoff between the Number of Sensors and the Resolution of Damage Localization, and (2) an Energy-Efficient, Multi-Level Computing Architecture Specifically Designed to Leverage the Multi-Resolution Feature of the Flexibility-Based Approach. the Proposed Approach Has Been Implemented …

Nanoporous And Microporous Solvogels And Nanolatexes By Microemulsion Polymerization, Feng Yan, John Texter

Patents

The present invention relates to microemulsions of immiscible fluids stabilized by reactive ionic liquid surfactant wherein the ionic liquid surfactant has a melting point less than 80 ° C. The invention also relates to composite materials comprising a copolymer of ethylenically reactive species, wherein one of the species is a reactive ionic liquid surfactant having a melting point less than 80 ° C., and wherein the material also comprises non-reactive Class I fluid. The invention further relates to methods for synthesizing the composite materials comprising preparing a microemulsion of immiscible Class I fluid and Class II fluid stabilized by reactive …

Room-Temperature Protonic Conduction In Nanocrystalline Films Of Yttria-Stabilized Zirconia, Hugo J. Avila-Paredes, Enrique Barrera-Calva, Harlan U. Anderson, Roger A. De Souza, Manfred Martin, Zuhair A. Munir, Sangtae Kim

Materials Science and Engineering Faculty Research & Creative Works

We report the results of our investigation on protonic conduction in 1 µm-thick polycrystalline films of 8 mol% yttria-stabilized zirconia (YSZ) with an average grain size of 17 nm prepared on sapphire substrate using a spin-coating process. Protonic conductivity of the films is found to be higher by over an order of magnitude (at 30 °C) than earlier reported values for nanocrystalline YSZ bulk ceramics with a similar grain size. This value is comparable to the oxygen-ionic conductivity of this material presented at about 400 °C. These results suggest that, besides grain size, the structural characteristics of the grain boundaries …

Characterizing Accuracy Of Total Hemoglobin Recovery Using Contrast-Detail Analysis In 3d Image-Guided Near Infrared Spectroscopy With The Boundary Element Method, Hamid R. Ghadyani, Subhadra Srinivasan, Brian W. Pogue, Keith D. Paulsen

Dartmouth Scholarship

The quantification of total hemoglobin concentration (HbT) obtained from multi-modality image-guided near infrared spectroscopy (IG-NIRS) was characterized using the boundary element method (BEM) for 3D image reconstruction. Multi-modality IG-NIRS systems use a priori information to guide the reconstruction process. While this has been shown to improve resolution, the effect on quantitative accuracy is unclear. Here, through systematic contrast-detail analysis, the fidelity of IG-NIRS in quantifying HbT was examined using 3D simulations. These simulations show that HbT could be recovered for medium sized (20mm in 100mm total diameter) spherical inclusions with an average error of 15%, for the physiologically …

Low Viscosity Pore Fluid To Manufacture Transparent Soil, Honghua Zhao, Louis Ge, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Transparent soil has been investigated for its potential as a substitute research media for natural soil. the mechanism for manufacturing the transparent soil is through adding an appropriate pore fluid to silica gel particles with the same refractive index. Two types of high viscosity pore fluids were identified by Iskander in 1994. However, because of the high viscosity of these two pore fluids, air was easily entrapped, which made the manufacture of a large mass of transparent soil difficult. in addition, the identified pore fluids caused serious membrane deterioration during triaxial laboratory testing. This research presented herein is an experimental …

A Methodology To Evaluate Obsolete Inventory In Health Care, Rama Thummalapalli

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

Many organizations are currently facing inventory management problems such as distributing inventory on-time and maintain the correct inventory levels to satisfy the customer or end users. Organizations understand the need for maintaining the accurate inventory levels but sometimes fall short leading a wide performance gap in maintaining inventory accurately. The inventory inaccuracy can consume much of the investment on purchasing inventory and many times leads to excessive inventory. The research objective of thesis is to provide a decision making criteria to the management for closing or maintaining the warehouse based on basic purchasing and holding cost information. The specific objectives …

A Reconfigurable Pattern Matching Hardware Implementation Using On-Chip Ram-Based Fsm, Nader I. Rafla, Indrawati Gauba

Electrical and Computer Engineering Faculty Publications and Presentations

The use of synthesizable reconfigurable IP cores has increasingly become a trend in System on Chip (SoC) designs because of their flexibility and powerful functionality. The market introduction of multi-featured platform FPGAs equipped with embedded memory and processor blocks has further expanded the possibility of utilizing dynamic reconfiguration to improve overall system adaptability to meet varying product requirements. In this paper, a reconfigurable hardware implementation for pattern matching using Finite State machine (FSM) is proposed. The FSM design is RAMbased and is reconfigured on the fly through altering memory contents only. An embedded processor is used for orchestrating run time …

A Hotspot-Based Protocol For Attack Traceback In Mobile Ad Hoc Networks, Hungyuan Hsu, Sencun Zhu, Ali Hurson

Electrical and Computer Engineering Faculty Research & Creative Works

based on the principle of divide and conquer, in this paper we propose an efficient traceback protocol for mobile ad hoc networks, the protocol is capable of detecting a hotspot where the attacker resides. It works by dividing the forwarding path of every packet into multiple interweaving fragments and each reachable fragment is individually reconstructed during a traceback process. through simulations in theoretical mobility models as well as real mobility traces, we show that each traceback of our scheme can attribute to a very small hotspot and the attacker can be accurately identified after a number of traceback operations. © …

Investigations Of Femtosecond-Nanosecond Dual-Beam Laser Ablation Of Dielectrics, Cheng Hsiang Lin, Zheng Hua Rao, Lan Jiang, Wu Jung Tsai, Ping Han Wu, Chih Wei Chien, Shean Jen Chen, Hai Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We have conducted experimental investigations for the micromachining of dielectrics (fused silica) using an integrated femtosecond (is) and nanosecond (ns) dual-beam laser system at different time delays between the fs and ns pulses. We found that the maximum ablation enhancement occurs when the fs pulse is shot near the peak of the ns pulse envelope. Enhancements up to 13.4 times in ablation depth and 50.7 times in the amount of material removal were obtained, as compared to fs laser ablation alone. the fs pulse increases the free electron density and changes the optical properties of fused silica to have metallic …

Numerical Simulation Of Atmospheric Internal Waves With Time-Dependent Critical Levels And Turning Points, Brian Patrick Casaday

Theses and Dissertations

Just as water surface waves are found everywhere on the ocean's surface, internal waves are ubiquitous throughout the atmosphere. These waves constantly propagate and interact with other flows, but these interactions are difficult to observe due to inadequate current technology. Numerical simulations are often utilized in the study of internal waves. In this work, ray theory is used to numerically simulate the interaction of atmospheric internal waves with time-dependent and time-independent background flows, specifically the interaction of small-scale internal waves and large-scale inertial waves. Parameters such as initial wavenumbers and amplitudes of both small internal waves and inertial waves are …

An Experimental Investigation Of Friction Bit Joining In Az31 Magnesium And Advanced High-Strength Automotive Sheet Steel, Rebecca Gardner

Theses and Dissertations

Friction Bit Joining (FBJ) is a recently developed spot joining technology capable of joining dissimilar metals. A consumable bit cuts through the upper layer of metal to be joined, then friction welds to the lower layer. The bit then snaps off, leaving a flange. This research focuses on FBJ using DP980 or DP590 steel as the lower layer, AZ31 magnesium alloy as the top layer, and 4140 or 4130 steel as the bit material. In order to determine optimal settings for the magnesium/steel joints, experimentation was performed using a purpose-built computer controlled welding machine, varying factors such as rotational speeds, …

Investigation Of Buildup Dose For Therapeutic Intensity Modulated Photon Beams In Radiation Therapy, Khosrow Javedan

USF Tampa Graduate Theses and Dissertations

Buildup dose of Mega Voltage (MV) photon beams can be a limiting factor in intensitymodulated radiation therapy (IMRT) treatments. Excessive doses can cause patient discomfort and treatment interruptions, while underdosing may lead to local failure.

Many factors which contribute to buildup dose, including the photon beam energy spectrum, scattered or contaminant radiation and their angular distribution, are not modeled well in commercial treatment planning systems. The accurate Monte Carlo method was employed in the studies to estimate the doses.

Buildup dose of 6MV photon beams was investigated for three fundamentally different IMRT modalities: between Helical TomoTherapy and traditional opposed tangential …

Analyzing The Effectiveness Of Safety Measures Using Bayesian Methods, Daniel J. Thurgood

Theses and Dissertations

Recent research has shown that traditional safety evaluation methods have been inadequate in accurately determining the effectiveness of roadway safety measures. In recent years, advanced statistical methods have been utilized in traffic safety studies to more accurately determine the effectiveness of roadway safety measures. These methods, particularly hierarchical Bayesian statistical techniques, have the capabilities to account for the shortcomings of traditional methods. Hierarchical Bayesian modeling is a powerful tool for expressing rich statistical models that more fully reflect a given problem than a simpler model could. This paper uses a hierarchical Bayesian model to analyze the effectiveness of two types …

Impedance Imaging And Measurements By Micro Probes In Aqueous Environments, Tao Shang

Theses and Dissertations

The dissertation presented here describes two research projects that may, at first glance, seem unrelated. Their unifying principle is the measurement of electrical impedance for the detection and analysis of biological materials. Impedance measurements have long been employed and studied in scientific fields, and the dissertation begins with a summary of historical methodology, applications, and terminology. Utilizing impedance measurements for microscopic imaging is the driving motivation for Scanning Impedance Imaging (SII). This technique manifests the distribution of electrical impedance inside biological tissues and is described after the dissertation's introduction. SII can provide micron-scale imaging resolution by scanning a shielded microprobe …

Influence Of Material And Geometric Parameters On The Flow-Induced Vibration Of Vocal Folds Models, Brian A. Pickup

Theses and Dissertations

The vocal folds are an essential component of human speech production and communication. Advancements in voice research allow for improved voice disorder treatments. Since in vivo analysis of vocal fold function is limited, models have been developed to simulate vocal fold motion. In this research, synthetic and computational vocal fold models were used to investigate various aspects of vocal fold vibratory characteristics. A series of tests were performed to quantify the effect of varying material and geometric parameters on the models' flow-induced responses. First, the influence of asymmetric vocal fold stiffness on voice production was evaluated using life-sized, self-oscillating vocal …

East Bay Energy Consortium Meeting Minutes, July 12, 2010, East Bay Energy Consortium

East Bay Energy Consortium Meeting Minutes

No abstract provided.

The Future Is Urban, Where ‘Up Mayo’ Politics Just Won’T Do, Lorcan Sirr, Conor Skehan

Media

No abstract provided.

Improving Surveying Accuracy And Efficiency In Connecticut: An Accuracy Assessment Of Geoid03 And Geoid09, Thomas H. Meyer, Robert Baron

Department of Natural Resources and the Environment Articles

Comparing published NAVD 88 Helmert orthometric heights of First-Order bench marks against GPS-determined orthometric heights showed that GEOID03 and GEOID09 perform at their reported accuracy in Connecticut. GPS-determined orthometric heights were determined by subtracting geoid undulations from ellipsoid heights obtained from a network least-squares adjustment of GPS occupations in 2007 and 2008. A total of 73 markers were occupied in these stability classes: 25 class A, 11 class B, 12 class C, 2 class D bench marks, and 23 temporary marks with transferred elevations. Adjusted ellipsoid heights were compared against OPUS as a check. We found that: the GPS-determined orthometric …

Wireless Sensor Network Approach To Aeronautical Telemetry, Oluwasegun Babatunde Tinubi

Theses and Dissertations

Wireless sensor networks have become a rapidly growing research field in recent years. They are envisioned to have a wide range of applications in military, environmental and many other fields. We examine the performance of wireless sensor network applications to aeronautical telemetry. To date, test ranges have relied on a single telemetry ground station for the reception of packets from all air borne transmitters. We researched an alternate means of achieving this same goal with fewer resources. It is a well known fact that communication power and bandwidth are the most expensive commodities in wireless communications. The telemetry world is …

A New Eulerian-Based Double Continuity Model For Predicting The Evolution Of Pair Correlation Statistics Under Large Plastic Deformations, Sadegh Ahmadi

Theses and Dissertations

A new model using a double-continuity relation for predicting the evolution of pair-correlation functions (PCFs) is presented. The proposed model was developed using statistical continuum theory and is employed to predict the viscoplastic behavior of polycrystalline materials. This model was built based upon the continuity relations and a double divergence law that guarantees the conservation of both orientation and mass; and also satisfies the field equations (equilibrium, constitutive, and compatibility) at every point of the polycrystalline material throughout the deformation process. In the presented model, motion of particles in the real space and rotation of crystallographic orientations in the Euler …

Modeling, Design, And Testing Of Contact-Aided Compliant Mechanisms In Spinal Arthroplasty, Peter Andrew Halverson

Theses and Dissertations

Injury, instrumentation, or surgery may change the functional biomechanics of the spine. Spinal fusion, the current surgical treatment of choice, stabilizes the spine by rigid fixation, reducing spinal mobility at the cost of increased stress at adjacent levels. Recently, alternatives to spinal fusion have been investigated. One such alternative is total disc replacements. The current generation of total disc replacements (TDRs) focuses on restoring the quantity of motion. Recent studies indicate that the moment-rotation response and axis of rotation, or quality of motion (QOM), may have important implications in the health of adjacent segments as well as the health of …

A Computational Fluid Dynamics Feature Extraction Method Using Subjective Logic, Clifton H. Mortensen

Theses and Dissertations

Computational fluid dynamics simulations are advancing to correctly simulate highly complex fluid flow problems that can require weeks of computation on expensive high performance clusters. These simulations can generate terabytes of data and pose a severe challenge to a researcher analyzing the data. Presented in this document is a general method to extract computational fluid dynamics flow features concurrent with a simulation and as a post-processing step to drastically reduce researcher post-processing time. This general method uses software agents governed by subjective logic to make decisions about extracted features in converging and converged data sets. The software agents are designed …

Interaction Designers’ Conceptions Of Design Quality For Interactive Artifacts, Mattias Arvola

DRS Biennial Conference Series

It is important to be aware of different ways of seeing design quality of interactive artifacts in order to appreciate the various aspects of a design, but how do professional interaction designers understand design quality? In theory, one way of approaching design quality of interactive artifacts has been the Vitruvian principles of commodity, firmness and delight, originally created for architecture. Such frameworks are, however, seldom directly employed in practice. This paper investigates what conceptions professional interaction designers have of design quality for interactive artifacts. Interviews were conducted with ten designers. The analysis disclosed four conceptions concerning: (a) Constraints & contexts, …

Crystallization Method For Benzphetamine, Dennis J. Kalota, Keith Tomazi

Chemical and Biochemical Engineering Faculty Research & Creative Works

There is disclosed a method for the crystallization of benzphetamine hydrochloride from an organic medium by the steps of removing water from the system to a very low level and then reducing the temperature of the organic medium to provide crystallization of the acid salt. In the event that crystallization does not occur upon lowering the temperature of the medium, it has been discovered that gentle heating of the organic medium results in crystallization of the acid salt. It has also been discovered that higher temperature crystallization has been provided by removal of methamphetamine from the composition. The crystalline benzphetamine …

An Examination Of Distributed Hydrologic Modeling Methods As Compared With Traditional Lumped Parameter Approaches, Murari Paudel

Theses and Dissertations

Empirically based lumped hydrologic models have an extensive track record of use where as physically based, multi-dimensional distributed models are evolving for various engineering applications. Despite the availability of high resolution data, better computational resources and robust numerical methods, the usage of distributed models is still limited. The purpose of this research is to establish the credibility and usability of distributed hydrologic modeling tools of the United States Army Corps of Engineers (USACE) in order to promote the extended use of distributed models. Two of the USACE models were used as the modeling tools for the study, with Gridded Surface …

Application Of A Bayesian Inference Method To Reconstruct Short-Range Atmospheric Dispersion Events, Inanc Senocak

Mechanical and Biomedical Engineering Faculty Publications and Presentations

In the event of an accidental or intentional release of chemical or biological (CB) agents into the atmosphere, first responders and decision makers need to rapidly locate and characterize the source of dispersion events using limited information from sensor networks. In this study the stochastic event reconstruction tool (SERT) is applied to a subset of the Fusing Sensor Information from Observing Networks (FUSION) Field Trial 2007 (FFT 07) database. The inference in SERT is based on Bayesian inference with Markov chain Monte Carlo (MCMC) sampling. SERT adopts a probability model that takes into account both positive and zero-reading sensors. In …