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Articles 2791 - 2820 of 4850

Full-Text Articles in Engineering

A Compliant Orthoplanar Piezoelectric Actuator, Aaron Shelley, Dr. Larry Howell Jan 2014

A Compliant Orthoplanar Piezoelectric Actuator, Aaron Shelley, Dr. Larry Howell

Journal of Undergraduate Research

This research focused on developing a new actuator/motor by integrating two previously unrelated technologies. In the past, piezoelectric crystals have been used primarily to measure acceleration in the engineering field, because of their unique nature of generating electricity when changes in their position occur. Modern researchers now use piezoelectric crystals in the opposite way, in that they put electricity through the crystals, causing them to expand or contract. The ability to cause the crystals to expand/contract merely by having a voltage difference across the crystal represents a whole new method of creating actuators/motors.

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The Brain’S Response To Music Using Fmri, Todd Harris, Dr. Travis Oliphant Jan 2014

The Brain’S Response To Music Using Fmri, Todd Harris, Dr. Travis Oliphant

Journal of Undergraduate Research

While it is obvious that hearing a sound produces measurable changes in the brain’s auditory cortex, it is less clear how a compilation of tones, beats, and rhythms affect other areas. In this study I use fMRI to observe which structures in the brain become active in response to music in three male subjects. My results show that different music pieces have unique and measurable affects on the brain. A strong determining factor on the effect that music has is the familiarity of the music to the listener. Results show that familiar music reduces overall brain activity while stimulating a …

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Gps Navigation Module For The Handspring Visor Pda, Craig Cody, Craig Tingey, Richard Helps Jan 2014

Gps Navigation Module For The Handspring Visor Pda, Craig Cody, Craig Tingey, Richard Helps

Journal of Undergraduate Research

The focus of our research project was to build a GPS navigation module to be used with the Handspring PDA. It provides a highly mobile method of finding exact locations using an interface and display that is familiar and friendly. Our GPS module fits into the Springboard expansion slot. With it, any Handspring user is able to choose from many available Palm OS location and positioning programs to harness GPS information wherever they choose to go. Research into GPS receivers began about two years ago with a project to build a high frequency antenna and low-noise amplifier to receive the …

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Design Of Equipment To Test Compliant Centrifugal Clutches, Nathan B. Crane, Dr. Larry L. Howell Jan 2014

Design Of Equipment To Test Compliant Centrifugal Clutches, Nathan B. Crane, Dr. Larry L. Howell

Journal of Undergraduate Research

A compliant mechanism is a mechanism in which some or all motion comes from deflection of its members. Several years ago, a one piece centrifugal clutch based on a compliant mechanism was developed and implemented in several products. It offers many cost and assembly advantages over traditional clutch designs containing at least five components.

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Gps Navigation Module For The Handspring Visor Pda, Craig Cody Hardcastle, Craig Tingey, Richard Helps Jan 2014

Gps Navigation Module For The Handspring Visor Pda, Craig Cody Hardcastle, Craig Tingey, Richard Helps

Journal of Undergraduate Research

The focus of our research project was to build a GPS navigation module to be used with the Handspring PDA. It provides a highly mobile method of finding exact locations using an interface and display that is familiar and friendly. Our GPS module fits into the Springboard expansion slot. With it, any Handspring user is able to choose from many available Palm OS location and positioning programs to harness GPS information wherever they choose to go. Research into GPS receivers began about two years ago with a project to build a high frequency antenna and low-noise amplifier to receive the …

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Waste Not, Want Not, Mary Cragun, Dr. William Hecker Jan 2014

Waste Not, Want Not, Mary Cragun, Dr. William Hecker

Journal of Undergraduate Research

The treatment of wastewater or sewage is a multi-step process. One of the steps involves the treatment of the organic mass collected during the treatment process. There are several different methods of treating this organic mass or sludge. At the Springville Wastewater Treatment Facility, the sludge is decomposed under anaerobic conditions into simpler forms of organic solids for safe disposal. Two different types of bacteria are used to decompose the sludge. The products of the sludge decomposition are methane, carbon dioxide, water, and simpler organic solids. The amount of methane produced by the bacteria depends on the system used and …

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A Stable Coating For Silica Supported Fisher-Tropsch Catalysts, Nathan M. Cluff, Dr. Calvin Batholomew Jan 2014

A Stable Coating For Silica Supported Fisher-Tropsch Catalysts, Nathan M. Cluff, Dr. Calvin Batholomew

Journal of Undergraduate Research

Our daily lives are dependent upon petroleum. This is evident in the fact that 26.4% of the United States’ energy consumption is used directly for transportation in the form of liquid fuels.1 To prevent shortages in gasoline, jet fuel, home heating oil, and other petroleum products, alternatives will be needed to supplement the rising world demand. As a citizen that will raise a family during a time when alternative energy sources will need to be implemented, I have a keen interest in how we will meet our energy needs and where we will get those resources. One alternative is the …

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The Developing Length Of Electro-Osmotic Flow, Joseph Scott Tenny, Dr. Daniel Maynes Jan 2014

The Developing Length Of Electro-Osmotic Flow, Joseph Scott Tenny, Dr. Daniel Maynes

Journal of Undergraduate Research

Recent advancements in technology have created the need for increased understanding of fluid flow in microtubes with a diameter of a 100μm or less. These types of flows can occur in many practical applications, one of which is a concept proposed for DNA analysis called “lab on a chip.” At this physical scale, the pressures required to drive the flow of the fluid are often too large for any type of potential application. An alternative approach to driving the fluid through a microtube is to use electro-osmosis. This type of flow uses an applied voltage potential to drive the fluid …

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Fmri Investigation Of Brain Function While Reading Different Types Of Literature, David A. Thayer, Dr. Travis Oliphant Jan 2014

Fmri Investigation Of Brain Function While Reading Different Types Of Literature, David A. Thayer, Dr. Travis Oliphant

Journal of Undergraduate Research

Functional Magnetic Resonance Imaging is a new imaging technique that results in images showing what areas of the brain are active during different activities. In spite of the popularity of this new technology there are no commonly available or widely accepted programs for processing fMRI data. The purpose of this research was to develop an fMRI analysis program, design a simple fMRI experiment, select MRI imaging parameters for fMRI, show that the program provides useful results, and then explore the results of another fMRI research experiment. This project’s focus turned more towards image processing than actual brain function mapping, as …

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The Brain’S Response To Physical Activity Studied With Fmri, Ren Weidman, Dr. Travis Oliphant Jan 2014

The Brain’S Response To Physical Activity Studied With Fmri, Ren Weidman, Dr. Travis Oliphant

Journal of Undergraduate Research

In recent years the fields of medicine and physiological research have made many advancements as a result of application of technology. One example of this is the device known as the Magnetic Resonance Imaging machine (MRI). MRI machines use innovative methods based on principles of physics and electronics to effectively attain a cross-sectional view of the human body. The MRI machine emits an electromagnetic field in the presence of a static field to manipulate the nuclear spin of hydrogen atoms in the body. The received signal can then be interpreted and reconstructed to plot a picture of the section examined. …

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Deactivation Of V2o5-Based Catalysts Used In The Selective Catalytic Reduction Of Nox, Aaron Nackos, Dr. Calvin H. Bartholomew Jan 2014

Deactivation Of V2o5-Based Catalysts Used In The Selective Catalytic Reduction Of Nox, Aaron Nackos, Dr. Calvin H. Bartholomew

Journal of Undergraduate Research

Nitric oxides (NO and NO2, or NOx for short) are significant contributors to photochemical smog and acid rain and are mainly produced from automobile emissions and from coal combustion used to generate electric power. Because of these issues, the EPA will require by the year 2004 that NOx emissions from coal-fired plants in this country meet strict pollution limitations—up to a 90% reduction in the amount of NOx currently allowed to be released by the EPA (Belden 41).

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The Effects Of Tool And Temperature Parameters On Grain Growth In Friction Stir Welded 7050 And 7475 Aluminum, Kevin Allen Schwendiman, Dr. Tracy Nelson, Dr. Carl Sorenson Jan 2014

The Effects Of Tool And Temperature Parameters On Grain Growth In Friction Stir Welded 7050 And 7475 Aluminum, Kevin Allen Schwendiman, Dr. Tracy Nelson, Dr. Carl Sorenson

Journal of Undergraduate Research

The Welding Institute (TWI) in Cambridge, England invented friction stir welding (FSW) late in 1991. TWI applied in December of that year for worldwide patent protection. The friction stir welding process is simple, energy-efficient and inexpensive relative to other welding methods. FSW can be implemented to make high quality welds with the most versatility – meaning the process can be used in almost all positions. Tensile, fatigue and bending tests have demonstrated that the properties of friction stir welded materials are superior to those made by other welding methods such as fusion or arc welding.

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Static Strength And Durability Testing Of Biomass Fly Ash In Concrete, John Hema, Dr. Fernando Fonseca Jan 2014

Static Strength And Durability Testing Of Biomass Fly Ash In Concrete, John Hema, Dr. Fernando Fonseca

Journal of Undergraduate Research

Fossil fuels are used in modern power plants throughout the world to produce electrical energy. This process increases air pollution and generates millions of tons of a by-product known as fly ash. Fly ash is the inorganic residue that remains after pulverized coal is burned. This residue rapidly accumulates and is often disposed of in landfills, filling them to capacity. One solution to reducing the amount of waste has been to use fly ash in concrete.

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An Analysis Of Beowulf Supercomputing Clusters, And Their Potential Application In Higher Education, Curtis R. Nielson, C. Richard G. Helps Jan 2014

An Analysis Of Beowulf Supercomputing Clusters, And Their Potential Application In Higher Education, Curtis R. Nielson, C. Richard G. Helps

Journal of Undergraduate Research

A supercomputer may be defined as a computer that leads the world in processing capacity, particularly in terms of calculation speed. Historically, the processing power of a supercomputer has been reserved for government or scientific research agencies; however, advances in computing technology have made the supercomputer an obtainable tool for academia. The Information Age has generated enormous amounts of data, which often require the processing capacity of a supercomputer for proper analysis. Modern supercomputers are well equipped to handle the demands of most data manipulations, but their cost is usually in the millions. A supercomputer design growing in popularity is …

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Low Reynolds Number Aerodynamics For Micro Air-Vehicles (Mav), Paul Nelson, Chad Lebaron, Bart Frischknecht, Kristopher Danielson, Jerry Bowman Jan 2014

Low Reynolds Number Aerodynamics For Micro Air-Vehicles (Mav), Paul Nelson, Chad Lebaron, Bart Frischknecht, Kristopher Danielson, Jerry Bowman

Journal of Undergraduate Research

Very little aerodynamic data exists for Reynolds numbers less than 100,000. It is common for there to be a large discrepancy between numerically predicted and experimental airfoil performance, especially at very low Reynolds numbers. In this research, a low Reynolds number airfoil was developed based on aerodynamic measurements.

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An Examination Of The Usefulness Of Lapping For Reducing Tip Leakage In Scroll Compressors, Jared W. Jensen, Paul Eastman, Jason Hugenroth Jan 2014

An Examination Of The Usefulness Of Lapping For Reducing Tip Leakage In Scroll Compressors, Jared W. Jensen, Paul Eastman, Jason Hugenroth

Journal of Undergraduate Research

Scroll compressors are unique in that the working fluid (in most cases, Freon or Puron™) is continuously compressed in an involute wrap. The geometry of the two scrolls is such that the gas is compressed towards the center in progressively smaller chambers as one scroll orbits the other. Before the gas is discharged, the involute returns to an intake state allowing the compressor to compress several “pockets” of refrigerant at the same time.

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Ground Water Modeling For Deseret Ranch In Deer Park, Florida, James Halgren, Dr. Wayne Downs Jan 2014

Ground Water Modeling For Deseret Ranch In Deer Park, Florida, James Halgren, Dr. Wayne Downs

Journal of Undergraduate Research

The original intent of this project was to create a groundwater model of the Deseret Ranch in Deer Park, Florida, in order to predict the possible detrimental effects of a 3,000-acre landfill planned for the area. Shortly after the acceptance of the proposal, the landfill plans were cancelled and the project had to be reconsidered. Sufficient issues with ranch hydrogeology exist to justify eventual creation of a model, so I changed my focus to collection of the pertinent data to accurately formulate such a model.

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Laboratory Design And Construction For Catalyst Characterization, Kenneth G. Crowther, Dr. Larry Baxter Jan 2014

Laboratory Design And Construction For Catalyst Characterization, Kenneth G. Crowther, Dr. Larry Baxter

Journal of Undergraduate Research

In the midst of industrial development we sometimes fail to foresee problems that may arise from current, seemingly economical, methods of production. One oversight in many industries ranging from Power to Caprolactam production is nitrogen oxide (NOX) emissions that damage our bodies and limit visibility. NOX are highly reactive molecules that are responsible for the formation of ground level ozone, acid aerosols, acid rain, and photochemical smog; all which pose a threat to the health of humans and other living things. This problem, however, is finally noticed. Government legislation is going into effect that is reducing the amounts of NOX …

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Computer Simulation Of Microstructures Based On Two-Point Correlation Functions, Benjamin L. Hansen, Dr. Brent Adams Jan 2014

Computer Simulation Of Microstructures Based On Two-Point Correlation Functions, Benjamin L. Hansen, Dr. Brent Adams

Journal of Undergraduate Research

A great amount of variance exists in the properties of any material. The ability to accurately predict these properties allows for designers to find the “best” material in highly constrained design situations. Many properties, such as elasticity and conductivity, are relatively insensitive to grain boundary interfaces and dislocations, and are thus accurately predicted by simple averaging techniques with a first-order description of the microstructure. However, many properties that effect lifetime to failure such as plastic yielding, intergranular stress corrosion cracking, and embrittlement are sensitive to dislocations and grain boundary interfaces. Therefore, second-order descriptions of the microstructures are needed to estimate …

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Enhanced High-Alphabet Fm For A Flight Termination System, Brent Allen Kenney, Dr. Michael D. Rice Jan 2014

Enhanced High-Alphabet Fm For A Flight Termination System, Brent Allen Kenney, Dr. Michael D. Rice

Journal of Undergraduate Research

The BYU Telemetry Lab has functioned in a consulting role for NASA’s Enhanced Flight Termination System (EFTS) group since 2000. NASA initiated the EFTS program to develop a new system to be used on their many test ranges for unmanned flight vehicles throughout the country. In the event that a flight vehicle loses control and threatens to endanger lives, the EFTS will place the vehicle in a zero-thrust state either by parachute or planned explosion. To ensure safety, the desired feature of EFTS is the reliability or the communication link rather than high data throughput.

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Use Of A Gradient-Based Search Method To Reconstruct The Temperature Profile Along An Optical Fiber Thermometer, David G. Barker, Dr. Matthew R. Jones Jan 2014

Use Of A Gradient-Based Search Method To Reconstruct The Temperature Profile Along An Optical Fiber Thermometer, David G. Barker, Dr. Matthew R. Jones

Journal of Undergraduate Research

Advances in the area of Optical Fiber Thermometry (OFT) are leading to more accurate temperature measurements in high-temperature environments. A typical OFT application is when the tip of an optical fiber is inserted into an environment where the temperature is to be measured. The other end of the fiber is attached to an optical system where light from the fiber is measured (see Figure 1). From the light emission measurements, the temperature at the heated tip of the fiber can be inferred.1

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Long Life Electrochemical Diodes For Continuous Electrowetting, Mehdi Khodayari, Ben Hahne, Nathan B. Crane Jan 2014

Long Life Electrochemical Diodes For Continuous Electrowetting, Mehdi Khodayari, Ben Hahne, Nathan B. Crane

Faculty Publications

The rate of electrochemical reactions in some systems varies with the polarity of the overpotential on the working electrode, introducing diode-like behavior at the electrode/electrolyte interface. However, with repeated bipolar cycling, the electrochemical current damages the electrodes. We have connected electrochemical diodes in series with opposing polarities to reduce the diode current while charging a capacitive circuit. We have previously used this capacitive circuit arrangement to actuate aqueous droplets continuously using the electrowetting (EW) effect. In this study, the performance of electrochemical diodes under repeated voltage cycles is investigated. Aluminum and titanium electrodes in contact with three electrolyte solutions (0.1 …

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Co2 Char Gasification Rates Of Sawdust, Switchgrass, And Corn Stover In A Pressurized Entrained-Flow Reactor, Thomas H. Fletcher, Aaron D. Lewis, Emmett G. Fletcher Jan 2014

Co2 Char Gasification Rates Of Sawdust, Switchgrass, And Corn Stover In A Pressurized Entrained-Flow Reactor, Thomas H. Fletcher, Aaron D. Lewis, Emmett G. Fletcher

Faculty Publications

An entrained-flow flat-flame burner reactor was used to measure apparent CO2 gasification rates of near-spherical biomass chars of poplar sawdust, switchgrass, and corn stover using particle residence times1258−1891 K and 6.1− 13.5 atm, respectively. A new method was developed to produce near-spherical particles from nonspherical biomass chars. The apparent CO2 gasification rates for the three biomass chars with mean diameters near 100 μm were fit to a global first-order model, and the optimal kinetic parameters are reported. The measured gasification rate of poplar sawdust was about 3.9 times faster than that of switchgrass char, but only about 20% faster than …

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Co2 Gasification Rates Of Petroleum Coke In A Pressurized Flat-Flame Burner Entrained-Flow Reactor, Aaron D. Lewis, Emmett G. Fletcher, Thomas H. Fletcher Jan 2014

Co2 Gasification Rates Of Petroleum Coke In A Pressurized Flat-Flame Burner Entrained-Flow Reactor, Aaron D. Lewis, Emmett G. Fletcher, Thomas H. Fletcher

Faculty Publications

Two petcoke samples were gasified by CO2 at total pressures of 10 and 15 atm in a high-pressure flat-flame burner reactor at conditions where the bulk phase consisted of either 40 or 90 mol % CO2 with gas temperatures up to 1909 K. Particle diameters of 45−75 μm were used in the experiments. The morphology of the two petroleum coke chars was drastically different and evaluated using scanning electron microscopy images of the chars. The mass release data caused by CO2 gasification of the petcoke chars were fit to a global first-order model, and the optimal kinetic parameters are reported. …

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Application Of L-Systems To Geometrical Construction Of Chamise And Juniper Shrubs, Dallan R. Prince, Marianne E. Fletcher, Chen Shen, Thomas H. Fletcher Jan 2014

Application Of L-Systems To Geometrical Construction Of Chamise And Juniper Shrubs, Dallan R. Prince, Marianne E. Fletcher, Chen Shen, Thomas H. Fletcher

Faculty Publications

Improved models of fire spread and fire characteristics are desired for live shrub fuels, since the majority of existing research efforts focus on either dead fuel beds or crown fires in trees. Efforts have been made to improve live fuel modeling, including detailed studies of individual leaf combustion, with results incorporated into a shrub combustion model for broadleaf species. However, this approach was not well-suited to non-broadleaf shrubs since their fuel consists of long needle-covered branches rather than easily discretized leaves. Methods were therefore developed to simulate the branching structure of chamise (Adenostoma fasciculatum) and Utah juniper (Juniperus osteosperma). The …

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Simulation Of The Swelling Of High-Volatile Bituminous Coal During Pyrolysis, He Yang, Sufen Li, Thomas H. Fletcher, Ming Dong Jan 2014

Simulation Of The Swelling Of High-Volatile Bituminous Coal During Pyrolysis, He Yang, Sufen Li, Thomas H. Fletcher, Ming Dong

Faculty Publications

In this paper, a model is established to predict the swelling ratio of high-volatile bituminous coal during pyrolysis, based on the assumption that the structure of bubble distribution in the particle at the beginning of the plastic stage is a central bubble surrounded by many surrounding bubbles. The initial number and size of the bubbles when the particles become plastic are calculated by the pressure in the particle. The chemical percolation devolatilization (CPD) model is used to describe pyrolysis. The pyrolysis of eight types of high-volatile bituminous coals is simulated, and the results are compared with experimental results to verify …

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Simulation Of The Evolution Of Pressure In A Lignite Particle During Pyrolysis, He Yang, Sufen Li, Thomas H. Fletcher, Ming Dong, Weishi Zhou Jan 2014

Simulation Of The Evolution Of Pressure In A Lignite Particle During Pyrolysis, He Yang, Sufen Li, Thomas H. Fletcher, Ming Dong, Weishi Zhou

Faculty Publications

The evolution of pressure in a lignite particle during pyrolysis was simulated on the basis of the gas motion equation in porous media and considering the Klinkenberg effect. The chemical percolation devolatilization (CPD) model was used to describe pyrolysis. The pore diameter in the particle is close to the average free path of volatile gas molecules; therefore, the solid phase restrains the movement of gas. Because flow out of the particle is restricted, the internal pressure rises. The internal pressure first increases and then decreases during pyrolysis, and the evolution is influenced by heating conditions. The pressure rise is larger …

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Characterization Of Macromolecular Structure Elements From A Green River Oil Shale, Ii. Characterization Of Pyrolysis Products By 13c Nmr, Gc/Ms, And Ftir, Thomas H. Fletcher, Ryan Gillis, Jacob Adams, Trent Hall Jan 2014

Characterization Of Macromolecular Structure Elements From A Green River Oil Shale, Ii. Characterization Of Pyrolysis Products By 13c Nmr, Gc/Ms, And Ftir, Thomas H. Fletcher, Ryan Gillis, Jacob Adams, Trent Hall

Faculty Publications

This paper is Part II of a study of the chemical structural components of the organic matter of oil shale in the Green River formation. Three sections of a well-characterized oil shale core from the Utah Green River formation were demineralized, and the resulting kerogen was pyrolyzed at 10 °C/min in nitrogen at atmospheric pressure at temperatures up to 525 °C. The pyrolysis products (light gas, tar, and char) were analyzed using 13C NMR, GC/MS, and (FTIR). Pyrolysis yields of 80% (daf basis) were achieved at these conditions, with 60% daf tar yield at the highest temperature. The solid-state …

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Characterization Of Macromolecular Structure Elements From A Green River Oil Shale, I. Extracts, Mark S. Solum, Charles L. Mayne, Anita M. Orendt, Ronald J. Pugmire, Jacob Adams, Thomas H. Fletcher Jan 2014

Characterization Of Macromolecular Structure Elements From A Green River Oil Shale, I. Extracts, Mark S. Solum, Charles L. Mayne, Anita M. Orendt, Ronald J. Pugmire, Jacob Adams, Thomas H. Fletcher

Faculty Publications

This paper is the first of two associated papers describing the structural details of three sections of an oil shale core taken at the Skyline 16 mine in the Utah Uinta Basin. Bitumen was extracted from the shale using methanol/dichloromethane. Kerogen was isolated from the shale, using a nine-step extraction procedure using HCl and HF. Bitumen samples from the three cores were analyzed using high-resolution 13C NMR liquid-state spectroscopy, showing carbon aromaticities of 7%−11%. Aliphatic carbons were dominated by methylene structures, with average aliphatic chain lengths of 24 carbons. The three parent shales and the demineralized kerogens were each …

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Optimal Trajectory Generation Using Model Predictive Control For Aerially Towed Cable Systems, Liang Sun, John Hedengren, Randal W. Beard Jan 2014

Optimal Trajectory Generation Using Model Predictive Control For Aerially Towed Cable Systems, Liang Sun, John Hedengren, Randal W. Beard

Faculty Publications

This paper studies trajectory generation for a mothership that tows a drogue using a flexible cable. The contributions of this paper include model validation for the towed cable system described by a lumped mass extensible cable using flight data, and optimal trajectory generation for the towed cable system with tension constraints using model predictive control. The optimization problem is formulated using a combination of the squared error and l1-norm objective functions. Different desired circular trajectories of the towed body are used to calculate optimal trajectories for the towing vehicle subject to performance limits and wind disturbances. Trajectory generation for transitions …

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