Engineering Commons^™

Life Cycle Analysis For Algae Biofuels-Using Local Situations To Factor In The Cost/Benefit Of High-End Products Along With Nutrient Remediation And Co2 Sequestration, John Korstad, Joe T. Moore

College of Science and Engineering Faculty Research and Scholarship

Algae as a feedstock for commercial biofuels is best suited for sunny and warm areas with abundant fresh, salt, or brackish water. Optimum areas worldwide are in the tropics. Logical areas in North America include the Southeast Gulf coast and perhaps New Mexico. Additional practical areas on smaller scale probably lie in metropolitan locations, especially near international airports. The cost-benefit of these endeavors can be enhanced when factors such as high-end products alongside collaboration with sewage treatment or other waste water remediation, industrial carbon dioxide sequestration, reduced transport distance of fuels, and other aspects of the local economy are taken …

On Linear Precoding Of Nonregenerative Mimo Relay Networks For Finite-Alphabet Source, Xiao Liang, Zhi Ding, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

Multiple input and multiple output (MIMO) relay could provide broader wireless coverage, better diversity, and higher throughput. Most existing precoder designs for either source or relay node are based on the assumption of Gaussian input signals. However, recent works have revealed possible performance loss of MIMO systems originally optimized for Gaussian source signals when applied to practical finite-alphabet source signals. In this work, we investigate the design problem of joint MIMO precoding for wireless two-hop nonregenerative cooperative relay networks under finite-alphabet source signals. We identify several structural properties of optimal precoders. Specifically, we provided the optimal left singular vectors of …

Spectroscopic Ellipsometry Studies On Zncdo Thin Films With Different Cd Concentrations Grown By Pulsed Laser Deposition, Shuai Chen, Qingxuan Li, Ian Ferguson, Tao Lin, Lingyu Wan, Zhe Chuan Feng, Liping Zhu, Zhizhen Ye

Electrical and Computer Engineering Faculty Research & Creative Works

A set of Zn 1-x Cd x O thin films with different Cd concentrations was deposited on quartz substrates by Pulsed Laser Deposition (PLD). The properties of these films were investigated by variable angle and temperature dependent spectroscopic ellipsometry (SE). The experimental Zn 1-x Cd x O thin films showed a red shift in the absorption edge with increasing Cd contents at room temperature. For ZnCdO films with the similar Cd concentration, it has been found that the film thickness has important effects on the optical constants (n, k). The variations of optical constants (n, k) and the band gap, …

Clutter Suppression Via Hankel Rank Reduction For Dfrft-Based Vibrometry Applied To Sar, Francisco Pérez, Balu Santhanam, Ranlf Dunkel, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

Hankel rank reduction (HRR) is a method that, by prearranging the data in a Hankel matrix and performing rank reduction via singular value decomposition, suppresses the noise of a time-history vector comprised of the superposition of a finite number of sinusoids. In this letter, the HRR method is studied for performing clutter suppression in synthetic aperture radar (SAR)-based vibrometry. Specifically, three different applications of the HRR method are presented. First, resembling the SAR slow-time signal model, the HRR method is utilized for separating a chirp signal immersed in a sinusoidal clutter. Second, using simulated airborne SAR data with 10 dB …

Energy-Efficient Fpga-Based Parallel Quasi-Stochastic Computing, Ramu Seva, Prashanthi Metku, Minsu Choi

Electrical and Computer Engineering Faculty Research & Creative Works

The high performance of FPGA (Field Programmable Gate Array) in image processing applications is justified by its flexible reconfigurability, its inherent parallel nature and the availability of a large amount of internal memories. Lately, the Stochastic Computing (SC) paradigm has been found to be significantly advantageous in certain application domains including image processing because of its lower hardware complexity and power consumption. However, its viability is deemed to be limited due to its serial bitstream processing and excessive run-time requirement for convergence. To address these issues, a novel approach is proposed in this work where an energy-efficient implementation of SC …

Broadband Infrared Absorbers With Stacked Double Chromium Ring Resonators, H. Deng, L. Stan, D. Czaplewski, Jie Gao, Xiaodong Yang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Study Of Defect Coalescence In Heterogeneous Material Systems Using Broad Band Dielectric Spectroscopy., Vamsee Vadlamudi, Muthu Ram Prabhu Elenchezhian, Priyanshu Kumar Banerjee, Rassel Raihan, Kenneth Reifsnider

Institute of Predictive Performance Methodologies (IPPM-UTARI)-Archive

Composite materials are essential for many modern applications, including airplanes and cars, energy conversion and storage devices, medical prosthetics, and civil structures. Detecting the initiation, growth, accumulation, and coalescence of micro-damage in these heterogeneous materials and predicting the onset of component failure using conformal Broadband Dielectric Spectroscopy (BbDS) is a promising area of ongoing research. Recently, the authors have developed the critical path concept and Heterogeneous fracture mechanics concept that depicts the effect of defect nucleation, growth, coalescence, and fracture plane development and correlation of these damage mechanisms to change in dielectric response respectively. Current research applies those concepts to …

Optimal Hemoglobin Extinction Coefficient Data Set For Near-Infrared Spectroscopy, Yue Zhao, Lina Qiu, Yunlong Sun, Chong Huang, Ting Li

Biomedical Engineering Faculty Publications

Extinction coefficient (ε) is a critical parameter for quantification of oxy-, deoxy-, and total-hemoglobin concentrations (Δ[HbO₂], Δ[Hb], Δ[tHb]) from optical measurements of Near-infrared spectroscopy (NIRS). There are several different ε data sets which were frequently used in NIRS quantification. A previous study reported that even a small variation in ε could cause a significant difference in hemodynamic measurements. Apparently the selection of an optimal ε data set is important for NIRS. We conducted oxygen-state-varied and blood-concentration-varied model experiments with 57 human blood samples to mimic tissue hemodynamic variations. Seven reported ε data sets were evaluated by comparisons between …

Techno-Economic Implications Of Fed-Batch Enzymatic Hydrolysis, Ellen Emanuel

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

As ethanol production continues to increase in the United States, cellulosic ethanol continues to gain traction as a viable option for meeting ethanol demands. In this work, a literature review of techno-economic analyses for cellulosic ethanol was conducted. It was found that pretreatment methods greatly affect the ethanol production costs. There is a lack of techno-economic data comparing a batch enzymatic hydrolysis to a fed-batch enzymatic hydrolysis for a separate hydrolysis and fermentation production process. Consequently, a techno-economic analysis comparing cellulosic ethanol production using batch versus fed-batch enzymatic hydrolysis was conducted. SuperPro Designer software (Intelligen, Scotch Plains, New Jersey), a …

Development And Characterization Of Piezoresistive Nanocomposites For Sensing Applications, Muhammad Anees

Doctoral Dissertations and Master's Theses

Carbonnanotube basedhybrid nanocomposites are known to exhibit remarkable electrical and mechanical properties with many potentials in strain and damage sensing applications. In this work, we fabricate hybrid nanocomposites with carbon nanotube (CNT) sheet and graphene nanoplatelets (GNP) as fillers with epoxy matrix. An improvement in both electrical conductivity and piezoresistivity is observed with the combination of CNTs and GNPs, indicating the formation of efficient hybrid conductive networks for strain and electrical transfer in the material. Different matrix materials have been compared to investigate the effect of matrix and to choose the one that yields increased strains, flexibility, and electromechanical response. …

Computer Aided Drafting Virtual Reality Interface, David M. Roach

Doctoral Dissertations and Master's Theses

Computer Aided Drafting (CAD) is pervasive in engineering fields today. It has become indispensable for planning, creating, visualizing, troubleshooting, collaborating, and communicating designs before they exist in physical form. From the beginning, CAD was created to be used by means of a mouse, keyboard, and monitor. Along the way, other, more specialized interface devices were created specifically for CAD that allowed for easier and more intuitive navigation within a 3D space, but they were at best stopgap solutions. Virtual Reality (VR) allows users to navigate and interact with digital 3D objects and environments the same way they would in the …

Analytical And Numerical Approaches On The Stiffness Of Magnetorheological Fluid Filled Spring, Stanislav Sikulskyi

Doctoral Dissertations and Master's Theses

A solid mechanical spring generally exhibits uniform stiffness. This thesis studies a mechanical spring filled with magnetorheological (MR) fluid to achieve controllable stiffness. The hollow spring filled with MR fluid is subjected to a controlled magnetic field in order to change the viscosity of the MR fluid and thereby to change the overall stiffness of the spring. MR fluid is considered as a Bingham viscoplastic linear material in the mathematical model. The goal of this research is to study the feasibility of such spring system by analytically and numerically computing the effects of MR fluid on the overall spring stiffness. …

Maritime Object Detection, Tracking, And Classification Using Lidar And Vision-Based Sensor Fusion, David John Thompson

Doctoral Dissertations and Master's Theses

Autonomous Surface Vehicles have the capability of replacing dull, dirty, and dangerous jobs in the maritime field. However, few successful ASV systems exist today, as there is a need for greater sensing capabilities. Furthermore, a successful ASV system requires object detection and recognition capabilities to enable autonomous navigation and situational awareness. This thesis demonstrates an application of LiDAR sensors in maritime environments for object detection, classification, and camera sensor fusion. This is accomplished through the integration of a high-fidelity GPS/INS system, 3D LiDAR sensors, and a pair of cameras. After rotating LiDAR returns into a global reference frame, they are …

Verification, Validation And Application Of Shear Stress Transport Transitional Model To A R/C Aircraft, Jon Willems

Doctoral Dissertations and Master's Theses

Accurate numerical prediction of transition onset as well as transition extent is crucial when evaluating the performance of many remotely controlled and autonomous aircraft. The four-equation Menter-Langtry Transitional viscous model in ANSYS Fluent is applied to a number of 2D and 3D airfoils and wings operating within the transitional flow regime, to permit comparison to relevant experimental and numerical results for transition onset, extent, and overall aerodynamic performance. The sensitivity to grid topology and fineness is also examined. With sufficient confidence in the numerical approach, the performance of a well-known high performance R/C glider is examined and compared to results …

Mission Tasking, Path Planning, And System Integration For An Autonomous Surface Vessel, Timothy Zuercher

Doctoral Dissertations and Master's Theses

This thesis presents the design and development of a fully autonomous surface vessel for use as a research platform for the Office of Naval Research and as a competition entry to the International Maritime RobotX Challenge in 2014 and 2016. The author’s contributions to this include the development of safety systems, power distribution systems, communications software, tasking software, and planning algorithms. The results of these developments include a hardware based safety system, a modular power and health monitoring system, an easy to use autoconfiguring inter-process communications stack, a dynamic tasking engine, and a comparison of two solutions to planning with …

Fast On-Line Kernel Density Estimation For Active Object Localization, Anthony D. Rhodes, Max H. Quinn, Melanie Mitchell

Computer Science Faculty Publications and Presentations

A major goal of computer vision is to enable computers to interpret visual situations—abstract concepts (e.g., “a person walking a dog,” “a crowd waiting for a bus,” “a picnic”) whose image instantiations are linked more by their common spatial and semantic structure than by low-level visual similarity. In this paper, we propose a novel method for prior learning and active object localization for this kind of knowledge-driven search in static images. In our system, prior situation knowledge is captured by a set of flexible, kernel-based density estimations— a situation model—that represent the expected spatial structure of the given situation. These …

Design And Prototyping Of A Shape-Changing Rigid-Body Human Foot In Gait, Tanner N. Rolfe

Honors Theses

Traditional ankle-foot prostheses often replicate the physiological change in shape of the foot during gait via compliant mechanisms. In comparison, rigid-body feet tend to be simplistic and largely incapable of accurately representing the geometry of the human foot. Multi-segment rigid-body devices offer certain advantages over compliant mechanisms which may be desirable in the design of ankle-foot devices, including the ability to withstand greater loading, the ability to achieve more drastic shape-change, and the ability to be synthesized from their kinematics, allowing for realistic functionality without prior accounting of the complex internal kinetics of the foot. This work focuses on applying …

Improving Electrochemical Devices Via Increased Charge Density And Ceramic Nanoparticles, George Padavick

Honors Theses

Challenges posed by climate change in conjunction with increasing global energy demand necessitate improved energy systems in both transportation and power delivery. These systems will require more advanced energy storage than current commercially available options. To enhance energy storage capabilities, supercapacitors were investigated to discover new mechanisms, materials, and fabrication techniques for developing electrochemical devices. In particular, methods for improving electrolyte performance were explored to enhance capacitance and conductivity. The results indicate that increasing charge density in the electrolyte via higher salt concentration or higher ionic charge of the solvated ions significantly increases capacitance. Specifically, a 0.1M solution of magnesium …

Design And Prototyping Of A Shape-Changing Rigid-Body Human Foot In Gait, Tanner N. Rolfe

Honors Theses

Traditional ankle-foot prostheses often replicate the physiological change in shape of the foot during gait via compliant mechanisms. In comparison, rigid-body feet tend to be simplistic and largely incapable of accurately representing the geometry of the human foot. Multi-segment rigid-body devices offer certain advantages over compliant mechanisms which may be desirable in the design of ankle-foot devices, including the ability to withstand greater loading, the ability to achieve more drastic shape-change, and the ability to be synthesized from their kinematics, allowing for realistic functionality without prior accounting of the complex internal kinetics of the foot. This work focuses on applying …

Composition And Temperature Dependent Optical Properties Of Al X Ga 1-X N Alloy By Spectroscopic Ellipsometry, Yao Liu, Qing Xuan Li, Ling Yu Wan, Bahadir Kucukgok, Ehsan Ghafari, Ian T. Ferguson, Xiong Zhang, Shuchang Wang, Zhe Chuan Feng, Na Lu

Electrical and Computer Engineering Faculty Research & Creative Works

A series of Al x Ga 1-x N/AlN/Sapphire films with x = 0.35–0.75 and different thickness of epi-layer were prepared by metalorganic chemical vapor deposition (MOCVD). Spectroscopic ellipsometry (SE) was used to study the temperature-dependent refractive indices and optical bandgaps of the Al x Ga 1-x N films ranging from 300 to 823 K. Parametric semiconductor (PSEMI) models were used to describe the dielectric functions of AlGaN/AlN layers. The fitting results of refractive index, energy bandgap, thickness and surface roughness at 300 K are in good agreement with photoluminescence (PL), scanning electron microscopy (SEM) measurements and the existing literature. Our …

Rapid Characterization Of Local Shape Memory Properties Through Indentation, Peizhen Li, Haluk E. Karaca, Yang-Tse Cheng

Mechanical Engineering Faculty Publications

Shape memory alloys (SMAs) have the ability to show large recoverable shape changes upon temperature, stress or magnetic field cycling. Their shape memory, material and magnetic properties (e.g. transformation temperatures, strain, saturation magnetization and strength) determine their prospects for applications from small-scale microelectromechanical systems to large scale aerospace and biomedical systems. It should be noted that properties of SMAs are highly temperature dependent. Generally, the conventional mechanical characterization methods (e.g, tension, compression, and torsion) are used on bulk samples of SMAs to determine those properties. In this article, it will be shown that indentation technique can be used as an …

Optical Properties Of Organic Carbon And Soot Produced In An Inverse Diffusion Flame, C. Russo, B. Apicella, J. S. Lighty, A. Ciajolo, A. Tregrossi

Mechanical and Biomedical Engineering Faculty Publications and Presentations

The carbonaceous matter (soot plus organic carbon) sampled downstream of an ethylene inverse diffusion flame (IDF) was chemically and spectroscopically analyzed in detail. In particular, the H/C ratio, the UV-Visible absorption coefficient and Raman parameters were measured and found to be representative of a highly disordered sp² -rich carbon as the early soot sampled in a premixed flame. In contrast, the optical band gap was found to be relatively low (0.7eV), closer to the optical band gap of graphite than to that of medium-sized polycyclic aromatic hydrocarbons (>2eV) which are widely considered to be soot precursors and are …

Incorporation Of Catalytic Modalities For Forming Of A Catalytic Cascade, Albert T. Perry Iii

Nanoscience and Microsystems ETDs

This dissertation investigates the novel incorporation of inorganic and enzymatic catalysts. There is little literature on inorganic catalysts operating at biologically relevant pHs and as such a significant amount of this dissertation focuses on determination of catalyst activity. Mn amino-anitpyrene (MnAAPyr), Pt, Pt alloys, Mn-N-C and Pd catalysts on 3D graphene supports(3D-GNS), were explored for activity towards glycerol intermediates: oxalic acid, mesoxalic acid, glyoxalic acid, and formic acid. MnAAPyr was designed to mimic the reaction center of oxalate decarboxylase and oxalate oxidaze, the natural catalyst towards oxalic acid. It showed high activity towards oxalic acid, with onset potentials of 0.714±0.002V …

Development Of Cardiac Atrial Kick Shear Wave Elastography To Assess Myocardial Stiffness, Aaron J. Engel

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

Increased myocardial stiffness, which is characteristic of many cardiovascular diseases, leads to a loss of diastolic function and is a cause of diastolic heart failure. Current methods to estimate myocardial stiffness rely on pressure-volume relationships derived from invasive cardiac catheter measurements. Noninvasive methods to estimate myocardial stiffness include ultrasound-based and magnetic resonance-based shear wave elastography, where the stiffness of the tissue is related to the propagation speed of a shear wave. Currently, ultrasound-based cardiac shear wave elastography includes acoustic radiation force based methods; however, the in vivo generation and detection of the shear waves in myocardium is significantly degraded due …

Highly Compressible Origami Bellows For Harsh Environments, Jared J. Butler

Theses and Dissertations

The use of origami-based bellows is of interest in fields where traditional metal bellows are incapable of meeting compression, mass, or flexibility constraints. Metal bellows are often used in space applications but frequently complicate spacecraft design. Origami-based bellows capable of meeting design constraints while adequately shielding sensitive spacecraft parts may be advantageous to space mechanism design. The design and testing of a highly compressible origami bellows for harsh environments is described. Several origami patterns were evaluated and the Kresling fold pattern was designed to meet constraints and selected for use in the bellows design. Origami bellows were prototyped in five …

Drained Elastoplastic Solution For Cylindrical Cavity Expansion In K0-Consolidated Anisotropic Soil, Jingpei Li, Weibing Gong, Lin Li, Fang Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This paper presents a semi analytical solution for drained expansion of a cylindrical cavity in K0-consolidated clay. The solution is derived based on the K0-based anisotropic modified Cam-clay model (K0-AMCC), which can properly consider the initial stress anisotropy and the initial stress-induced anisotropy of natural soils. Parametric studies are carried out to investigate the effects of different over consolidation ratios on the growth of plastic zone and cavity pressure, the distributions of the stress components and the specific volume around the cavity, and the effective stress path. The results are compared with the published solution based on the modified Cam-clay …

A Multiscale Modeling Study Of Particle Size Effects On The Tissue Penetration Efficacy Of Drug-Delivery Nanoparticles, Mohammad Aminul Islam, Sutapa Barua, Dipak Barua

Chemical and Biochemical Engineering Faculty Research & Creative Works

Background: Particle size is a key parameter for drug-delivery nanoparticle design. It is believed that the size of a nanoparticle may have important effects on its ability to overcome the transport barriers in biological tissues. Nonetheless, such effects remain poorly understood. Using a multiscale model, this work investigates particle size effects on the tissue distribution and penetration efficacy of drug-delivery nanoparticles.

Results: We have developed a multiscale spatiotemporal model of nanoparticle transport in biological tissues. The model implements a time-adaptive Brownian Dynamics algorithm that links microscale particle-cell interactions and adhesion dynamics to tissue-scale particle dispersion and penetration. The model accounts …

Metabolomic Effects Of Ceo₂, Sio₂ And Cuo Metal Oxide Nanomaterials On Hepg2 Cells, Kirk T. Kitchin, Steve Stirdivant, Brian L. Robinette, Benjamin T. Castellon, Xinhua Liang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Background: To better assess potential hepatotoxicity of nanomaterials, human liver HepG2 cells were exposed for 3 days to five different CeO₂ (either 30 or 100 μg/ml), 3 SiO₂ based (30 μg/ml) or 1 CuO (3 μg/ml) nanomaterials with dry primary particle sizes ranging from 15 to 213 nm. Metabolomic assessment of exposed cells was then performed using four mass spectroscopy dependent platforms (LC and GC), finding 344 biochemicals.

Results: Four CeO₂, 1 SiO₂ and 1 CuO nanomaterials increased hepatocyte concentrations of many lipids, particularly free fatty acids and monoacylglycerols but only CuO elevated lysolipids and …

Classification Of Rest And Active Periods In Actigraphy Data Using Pca, Isaac W. Muns, Yogesh Lad, Ivan G. Guardiola, Matthew S. Thimgan

Engineering Management and Systems Engineering Faculty Research & Creative Works

In this paper we highlight a clustering algorithm for the purpose of identifying sleep and wake periods directly from actigraphy signals. The paper makes use of statistical Principal Component Analysis to identify periods of rest and activity. The aim of the proposed methodology is to develop a quick and efficient method to determine the sleep duration of an individual. In addition, a robust method that can identify sleep periods in the accelerometer data when duration, time of day varies by individual. A selected group of 10 individual's sensor data consisting of actigraphy from an accelerometer (3-axis), near body temperature, and …

Energy Consumption Modeling Of Stereolithography-Based Additive Manufacturing Toward Environmental Sustainability, Yiran Yang, Lin Li, Yayue Pan, Zeyi Sun

Engineering Management and Systems Engineering Faculty Research & Creative Works

Additive manufacturing (AM), also referred as three-dimensional printing or rapid prototyping, has been implemented in various areas as one of the most promising new manufacturing technologies in the past three decades. In addition to the growing public interest in developing AM into a potential mainstream manufacturing approach, increasing concerns on environmental sustainability, especially on energy consumption, have been presented. To date, research efforts have been dedicated to quantitatively measuring and analyzing the energy consumption of AM processes. Such efforts only covered partial types of AM processes and explored inadequate factors that might influence the energy consumption. In addition, energy consumption …