Engineering Commons^™

Near Field Enhancement In Silver Nanoantenna-Superlens Systems, Zhengtong Liu, Erping Li, Vladimir M. Shalaev, Alexander V. Kildishev

Birck and NCN Publications

We demonstrate near field enhancement generation in silver nanoantenna-superlens systems via numerical modeling. Using near-field interference and global optimization algorithms, we can design nanoantenna-superlens systems with mismatched permittivities, whose performance can match those with matched permittivities. The systems studied here may find broad applications in the fields of sensing, such as field-enhanced fluorescence and surface-enhanced Raman scattering, and the methodology used here can be applied to the designing and optimization of other devices, such as two-dimensional near field focusing lens. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4732793]

A Thermophone On Porous Polymeric Substrate, Girish Chitnis, Albert Kim, Seung Hyun Song, A. M. Jessop, J. S. Bolton, Babak Ziaie

Birck and NCN Publications

In this Letter, we present a simple, low-temperature method for fabricating a wide-band (>80 kHz) thermo-acoustic sound generator on a porous polymeric substrate. We were able to achieve up to 80 dB of sound pressure level with an input power of 0.511 W. No significant surface temperature increase was observed in the device even at an input power level of 2.5 W. Wide-band ultrasonic performance, simplicity of structure, and scalability of the fabrication process make this device suitable for many ranging and imaging applications. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4737005]

A Server-Based Tool For Automating Modflow Simulations For Well Permitting Decision Support, David J. Jones

Theses and Dissertations

Numeric groundwater modeling techniques can assist water resources regulators pursuing prudent and foresightful aquifer management decisions. Unfortunately, the amount of time and professional expertise required to wield modern groundwater models often exceeds the resources of regulating agencies – even for simple modeling tasks that are repetitive in nature. In an effort to increase the accessibility of groundwater modeling resources, a server-based automated well permitting decision support system was designed. The prototype system allows a user to 1) input properties for any number of candidate wells, 2) execute an associated MOFLOW model, and 3) view relevant results of the simulation on …

Note: Utilizing Pb(Zr 0.95ti 0.05)O₃ Ferroelectric Ceramics To Scale Down Autonomous Explosive-Driven Shock-Wave Ferroelectric Generators, S. I. Shkuratov, Jason Baird, E. F. Talantsev

Mining Engineering Faculty Research & Creative Works

Further miniaturization of recently designed autonomous ferroelectric generators (FEGs) S. I. Shkuratov, J. Baird, and E. F. Talantsev, Rev. Sci. Instrum. 82, 086107 (2011), which are based on the effect of explosive-shock-wave depolarization of poled ferroelectrics is achieved. The key miniaturization factor was the utilization of high-energy density Pb(Zr_0.95Ti_0.05)O₃ (PZT 955) ferroelectric ceramics as energy-carrying elements of FEGs instead of the previously used Pb(Zr_0.52Ti_0.48)O₃ (PZT 5248). A series of experiments demonstrated that FEGs based on smaller PZT 955 ferroelectric elements are capable of producing the same output voltage as those …

Solar Light Bulb, David G. Guzman, Virgilio Gonzalez

COURI Symposium Abstracts, Summer 2012

The Solar Lighting project is a work driven towards building a low-cost and environmental-friendly solar bulb and to understanding the science behind its behavior. A solar light bulb refers to a device capable of absorbing and transferring solar energy to light up an enclosed area. By using the physical properties of fluids and light is possible to manipulate solar light waves to illuminate an enclosed structure. Moreover, this project attempts to utilize recycled materials that reduce the cost of such device, helping not only the planet but also the costumer’s pocket. The ultimate goal for this project is to scientifically …

Sic-Cnt Multifunctional Nanocomposites For High Temperature Structural, Thermoelectric And Sensing Applications, Salvador Sandoval, Luz I. Bugarin, Luz I, Arifur Chowdhury, Luisa A. Cabrera, Mujibur R. Khan

COURI Symposium Abstracts, Summer 2012

The purpose of this project is to study the thermal-electrical and mechanical properties of the Nanojunctions between Single-Wall Carbon Nanotubes (SWCNT) and Silicon Carbide (SiC). The mixture was done by spreading the nanoparticles in a solution of ethanol and SiC, then sintered to a solid sample of 10 mm x 10 mm x 35 mm, which was attached with Alumel (Ni-Al) wire using silver epoxy to form a circuit for recording during fracture testing. The carbon nanotubes used were approximately 60% semiconducting and 40% metallic. The themal-electrical effect changed when SWCNTs (at 2, and 5 wt%) were infused into SiC. …

3-D Vision And Motion Tracking, Alberto G. Fajardo, Olac Fuentes

COURI Symposium Abstracts, Summer 2012

Motion tracking in Computer Vision consists of determining the location and configuration of an object from a video sequence. The potential real world applications of motion tracking range from medical imaging and analysis to entertainment, as well as surveillance and security. Motion tracking is a difficult problem, especially if it is required to be done in real time, which is why it has been an active research area for the past couple of decades. In this project we are developing algorithms for tracking articulated objects, such as the human body, by exploiting the use of the Microsoft Kinect, an imaging …

Characterization Of Printed Skin Equivalents, Mayela R, Aldaz Cervantes, Maria Yanez, Thomas Boland

COURI Symposium Abstracts, Summer 2012

Severe burns, ulcerations, and cuts are some of the reasons people need bioengineered skin as a treatment for full-thickness wounds. When patients run out of donor sites in their own body, using the patient’s skin as a graft is no longer an option, and tissue-engineered constructs are the only possible replacement for damaged skin. The goal of this research is to develop a hydrogel-based skin graft that will be able to function as a skin replacement in full-thickness wounds while minimizing the possibility of rejection, being cost-effective, and possessing a longer shelf-life than the grafts currently in the market. Endothelial …

Smart Home System Prototype, Comparing And Evaluating Current Technologies, Marco Antonio López, David Guzman, Virgilio Gonzalez

COURI Symposium Abstracts, Summer 2012

Imagine a world where blackouts can be prevented, reduced, or even removed completely. This one of the many benefits a Smart Grid would bring. The integration of the Smart Grid would bring all these benefits by being able to transfer information through all stages of electricity; generation, distribution, and consumption. This research is concentrated on the Smart Home –the consumption stage of electricity. Specifically, on technologies available that can be used towards the designing of the Smart Home. Before being able to design a Smart Home, it is necessary to decide which technologies are best for the job; be it …

Nanowire-Graphene Hybrids For Li-Ion Insertion, Philip A. Morton, Mohammad Arif I. Shuvo, Yirong Lin

COURI Symposium Abstracts, Summer 2012

Lithium ion batteries are one of the most popular energy storage devices due to its high energy density. However, their performance is hindered by the limited surface area of the anode. This research focuses on the use of graphene nanowire hybrids and their performance as anode material. These hybrid structures have a greater surface area then graphite, the most common anode material. Greater surface area will enhance lithium ion insertion, and thus improve battery performance. The graphene oxide (GO) will be synthesized using the Hummer’s plus method. The GO will be sonicated and reduced in an argon furnace to form …

Research And Development Of An Extremely Affordable Prosthetic Knee, Victor H. Duenas, Noe Vargas-Hernandez

COURI Symposium Abstracts, Summer 2012

The objective of this research and development work is to apply the design process in a prosthetic knee mechanism. The importance of human knee is founded in the provided mobility, body positioning and support of the body weight. But for amputees, limitations for everyday tasks imply a real challenge. The project scope a cycle involving the social need, the development and the supply of the solution layout. The motivation is to improve life quality through voluntary and independent human movement by providing a low cost knee design.

The design process requires the conceptual, embodiment, detail and evaluation phases to complete …

Development Of A Vaccine Printer For Helicobacter Pylori, Gabriela Enriquez, Julio E. Rincon, Thomas Boland

COURI Symposium Abstracts, Summer 2012

Helicobacter pylori is present in approximately half of the world’s population, of which approximately 2% develop a type of gastric cancer. This cancer is often discovered when being in an advanced stage due to its lack of symptoms. Unfortunately, a vaccine hasn’t been successfully developed against the bacterium. Therefore, the aim of this research is to develop the functional prototype of a DNA vaccine printer. Its parts were designed in the program NX. 6.0 and built out of ABS plastic using printing technology at the University of Texas at El Paso. After being assembled, the printer will be programmed and …

Research And Development Of An Expert System In Idea Generation Methods To Aid In The Engineering Design Process, Rodrigo Enriquez, Noe Vargas-Hernandez

COURI Symposium Abstracts, Summer 2012

The objective of this research is to develop an Expert System (i.e. software) to aid designers in selecting appropriate idea generation methods for their specific design situation. This expert system would help designers generate creative ideas more frequently, and hence better designs and better products for society. The first step is to understand the creative design process in detail; this involves the engineering design process, cognitive processes, and other related elements. This understanding is represented initially as a conceptual model. Following an Artificial Intelligence (AI) approach, this model is then developed into a Logical model that defines entities, attributes, and …

Power Tac 2012: Agent Technologies For The Smart Grid, Carlos E. Montijo, Daniel H. Grajeda, Christopher Kiekintveld

COURI Symposium Abstracts, Summer 2012

Intelligent agents are a critical technology in managing the increasingly complex and decentralized energy systems that are evolving. These technologies, often called the "smart grid," have the potential to improve the efficiency and reliability of future energy markets. This project focuses on developing a trading agent to compete in the 2012 Power TAC game, a new scenario this year that is part of the annual Trading Agent Competition. Modeling a liberalized retail electrical energy market, Power TAC is a simulation in which competing trading agents or brokers offer energy services to customers via tariff contracts. The brokers must also serve …

Low Power Sigma Delta Converter, Noel P. Martinez, Praveen K. Palakurthi, Eric Macdonald

COURI Symposium Abstracts, Summer 2012

Sub threshold technology allows for circuits to run at their best efficiency with the lowest amount of energy possible. The aim of this research was to combine this technology along with radiation hardness, or the ability for circuits to resist radiation without getting corrupted data. A chip that can convert digital data into analog data (DAC) was created and programmed using verilog, a Hardware Description Language (HDL). With verilog, we created digital data that would eventually be fed into the chip using a field-programmable gate array (FPGA) board. We tested our digital data using a test bench on the computer …

Seismic Tomography And Smoothing Filters, Mathew Guevara, Olac Fuentes

COURI Symposium Abstracts, Summer 2012

Seismic Tomography and Smoothing Filters Seismic Tomography is a technique used by geologists to map the Earth's crust. Seismic Tomography is an iterative process that develops a model based on travel times of waves from explosion sites to sensors. First, travel times are gathered by using shot points and sensors. Then an optimization process begins with an initial simple model (velocity increasing monotonically with depth), is used to predict the travel times. These predictions are compared to the observed travel times, and the model is refined so that it can better match the observed data until a satisfactory solution is …

Electrophoretic Screen And Functionalized Microspheres As Antigen Assays, Alejandra Hernandez, Julio Rincon, Thomas Boland

COURI Symposium Abstracts, Summer 2012

Immunoassays are used for medical diagnosis of infectious diseases. People in developing countries usually do not have access to this type of technologies, which makes infectious diseases the main cause of death in these countries. Immunoassay techniques assist the medical field with diagnosing, prognosis and monitoring of analytes present in the human body. This project will develop a portable antigen detection assay built using an electrophoretic screen with functionalized microspheres. A portable electrophoretic immunoassay will permit the reduction of lab materials and the independence of lab installations making it more accessible. This project involves two main steps: The screen modification …

Molecular Imprinting Of Silica Microspheres On Human Chorionic Gonadotropin, Paulina Almada, Julio E. Rincon, Thomas Boland

COURI Symposium Abstracts, Summer 2012

The technique of molecule imprinting prepares polymers with specific binding sites for a target molecule. Monomers are polymerized with a template present, arranging into a polymer matrix that can rebind the template once removed and creates the potential use of the polymers as artificial antibodies. The same process can be used to synthesize silica microspheres .The aim of this study was to test the ability of silica microspheres to bind human chorionic gonadotropin and be used as antibodies. 26.4 ml of tetraethoxysilane, 4.7 ml of water, 6.6 ml of 0.12 M hydrochloric acid, and 11.5 ml of 70% ethanol were …

Rapid Oxidation Of Titanium And Its Alloys, Monica A. Cadena, Stephen Stafford

COURI Symposium Abstracts, Summer 2012

The tragedy of the Space Shuttle Columbia demonstrated the need for better understanding of materials in extreme environments. This study’s main objective was to provide more information about the behavior of materials, particularly Ti-6Al-4V, whenever conditions (such as temperature, pressure and behavior) change dramatically. The study included the microstructural analysis of Ti-6Al-4V samples that were exposed to conditions that approximate those encountered during re-entry by arc-jet experimentation. The analysis of these samples consisted of scanning electron microscopy and x-ray diffraction. The x-ray diffraction analysis showed the presence of several titanium oxides, such as Ti3-O and Ti6-O on different sections of …

Generating Minimal T-Wise Test Suites, Luis C. Gutierrez, Carlos Nieto, Francisco Zapata, Martine Ceberio

COURI Symposium Abstracts, Summer 2012

As the use of computing devices increases every day, users rely on the adequate functioning of software. When software is not tested properly, it can yield erroneous information or a complete failure of the system. The NIST estimates that defective software cost the United States economy close to $60 billion a year. Therefore, there is a need to develop software testing techniques that are time and cost effective. Fully testing software under all possible combinations of parameters values cannot be reduced. However, testing can focus on covering all combinations of subsets of parameters and empirical data shows that doing so …

Generating Minimal T-Wise Covering Test Suites Using Constraints, Carlos A. Nieto, Martine Ceberio

COURI Symposium Abstracts, Summer 2012

Software testing is an essential part of software development that seeks quality assurance, reliability, and robustness. Unfortunately, exhaustive testing can be a very expensive, time consuming, and tedious process. With large sets of inputs, exhaustive testing can result in unpractical test suites, of size that grows exponentially with the number of input parameters.

As a way to address this growth, t-wise testing consists in focusing on test suites that only cover the interactions of the t-tuples of input parameters of the system at hand. Adding constraints further restricts the size of the test suite by limiting the possible values of …

Improved Methods For Phased Array Feed Beamforming In Single Dish Radio Astronomy, Michael James Elmer

Theses and Dissertations

Among the research topics needing to be addressed to further the development of phased array feeds (PAFs) for radio astronomical use are challenges associated with calibration, beamforming, and imaging for single dish observations. This dissertation addresses these concerns by providing analysis and solutions that provide a clearer understanding of the effort required to implement PAFs for complex scientific research. It is shown that calibration data are relatively stable over a period of five days and may still be adequate after 70 days. A calibration update system is presented with the potential to refresh old calibrators. Direction-dependent variations have a much …

Culvert Roughness Elements For Native Utah Fish Passage: Phase Ii, Suzanne Kim Monk

Theses and Dissertations

Native fishes have become an increasingly important concern when designing fish passable culverts. Many operational culverts constrict waterways which increase velocities and prevent upstream passage of small fish species. The current method to ensure fish passage is to match the average cross sectional velocity to the sustained swim speed of the fish. This study investigates the passage rates of leatherside chub (Lepidomeda aliciae) and speckled dace (Rhinichthys osculus) at three sites (an arch culvert with substrate bottom, box culvert with bare bottom, and a stream section with no culvert) located on Salina Creek near Salina, UT. It was found that …

Order-Disorder Transition Of Aragonite Nanoparticles In Nacre, Zaiwang Huang, Xiaodong Li

Faculty Publications

Understanding nacre’s bottom-up biomineralization mechanism, particularly, how individual aragonite platelets are formed, has long remained elusive due to its crystallographic peculiarity and structural complexity. Here we report that crystallographic order-disorder transition can be triggered within individual aragonite platelets in pristine nacre by means of heat treatment and/or inelastic deformation, offering a unique opportunity to discriminate mysterious aragonite nanoparticles in transmission electron microscopy. Our findings unambiguously uncover why aragonite nanoparticles in pristine nacre have long been inaccessible under TEM observation, which is attributed to the monocrystal-polycrystal duality of the aragonite platelet. The underlying physical mechanism for why an individual aragonite platelet …

Cooling Of Photoexcited Carriers In Graphene By Internal And Substrate Phonons, Tony Low, Vasili Perebeinos, Raseong Kim, Marcus Freitag, Phaedon Avouris

Birck and NCN Publications

We investigate the energy relaxation of hot carriers produced by photoexcitation of graphene through coupling to both intrinsic and remote ( substrate) surface polar phonons using the Boltzmann equation approach. We find that the energy relaxation of hot photocarriers in graphene on commonly used polar substrates, under most conditions, is dominated by remote surface polar phonons. We also calculate key characteristics of the energy relaxation process, such as the transient cooling time and steady-state carrier temperatures and photocarrier densities, which determine the thermoelectric and photovoltaic photoresponse, respectively. Substrate engineering can be a promising route to efficient optoelectronic devices driven by …

Design And Optimization Of A Miniature Radiation Pattern Reconfigurable Antenna For 2.4 Ghz Band And A Dual Tuned Birdcage Coil For Magnetic Resonance Imaging, Manoj Adhikari

Theses and Dissertations

This thesis describes development of a miniature reconfigurable antenna and optimization of a dual tuned birdcage coil. The design goals for the miniature reconfigurable antennas are resonance center frequency of 2.44 GHz, bandwidth of 2.4 GHz - 2.48 GHz, size of 0.8 cm x 1.2 cm, radiation efficiency of 70%, pattern correlation coefficient of 0.3 and input impedance of 50 Ω. The main goals to be achieved from the birdcage coil are the better homogeneity and higher signal to noise ratio than the existing coil. The design and optimization of both antenna and birdcage coil were done using simulation software …

Toward A Gpu-Accelerated Immersed Boundary Method For Wind Forecasting Over Complex Terrain, Rey Deleon, Kyle Felzien, Inanc Senocak

Mechanical and Biomedical Engineering Faculty Publications and Presentations

A short-term wind power forecasting capability can be a valuable tool in the renewable energy industry to address load-balancing issues that arise from intermittent wind fields. Although numerical weather prediction models have been used to forecast winds, their applicability to micro-scale atmospheric boundary layer flows and ability to predict wind speeds at turbine hub height with a desired accuracy is not clear. To address this issue, we develop a multi-GPU parallel flow solver to forecast winds over complex terrain at the micro-scale, where computational domain size can range from meters to several kilometers. In the solver, we adopt the immersed …

An Enhanced Method To Measure Pulse Dispersion In Uwb Antennas, Antoine Dumoulin, Matthias John, Patrick Mcevoy, Max Ammann

Conference Papers

This paper will demonstrate a method to remove the dispersive effects of antennas and measurement equipment from a real time-domain measurement setup. By isolating the AUT transfer function, more accurate time-domain measurements can be achieved and agreement to simulation improved.

Vivaldi Array For Generation Of Uwb Circular Polarization, Adam Narbudowicz, Matthias John, Xiulong Bao, Max Ammann

Conference Papers

A two antenna array is proposed for generating circular polarization for an ultra-wideband system. It consists of two orthogonal antipodal vivaldi antennas and a feed network which provides the appropriate phase and amplitude over the band of interest. The proposed structure is low cost and easy to manufacture, offering an axial-ratio bandwidth of 74%.

Characterization And Preliminary Demonstration Of Microcantilever Array Integrated Sensors, Ryan R. Anderson

Theses and Dissertations

I characterize the behavior of microcantilever arrays which utilize the in-plane photonic transduction that I've previously developed and evaluate the performance of the microcantilever arrays in simple sensing scenarios with integrated microfluidics. First the thermal responses of microcantilevers with a variety of patterns of deposited gold films are compared. Using a scanning electron microscope, I observe the deflection thermal sensitivities of 300 µm long microcantilevers to be -170.82 nm/K for a full gold coating and -1.93 nm/K for no gold coating. Using the photonic transduction method I measure a thermal sensitivity of -1.46 nm/K for a microcantilever array with no …