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Full-Text Articles in Engineering

Analysis Of Sugar Beet Pulp By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford Dec 2005

Analysis Of Sugar Beet Pulp By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford

Faculty Publications

Determining the chemical structure and composition of biomass fuels using x-ray photoelectron spectroscopy XPS can provide fundamental knowledge of their structures that is useful in understanding and predicting their combustion behavior. Sugar beet pulp is an example of an agricultural residue byproduct of food and feed production of potential interest for biomass combustion. The XPS spectra of sugar beet pulp provide both its elemental composition and indications of its bonding. Traditional fuel analyses of this fuel are also provided. These include: ultimate analysis — the elemental composition of the overall fuel C, H, N, S, and O; chlorine analysis — …


Analysis Of Sawdust By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford Dec 2005

Analysis Of Sawdust By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford

Faculty Publications

Determining the chemical structure and composition of biomass fuels using x-ray photoelectron spectroscopy XPS can provide fundamental knowledge of their structures that is useful in understanding and predicting their combustion behavior. Sawdust is an example of a forest product residue byproduct of paper and lumber production of potential interest for biomass combustion. The XPS spectra of sawdust provide both its elemental composition and indications of its bonding. Traditional fuel analyses of this fuel are also provided. These include: ultimate analysis — the elemental composition of the overall fuel C, H, N, S, and O; chlorine analysis — reported here as …


Analysis Of Grain Screenings By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford Dec 2005

Analysis Of Grain Screenings By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford

Faculty Publications

Determining the chemical structure and composition of biomass fuels using x-ray photoelectron spectroscopy XPS can provide fundamental knowledge of their structures that is useful in understanding and predicting their combustion behavior. Grain screenings are an example of an agricultural residue byproduct of food and feed production of potential interest for biomass combustion. The XPS spectra of grain screenings provide both its elemental composition and indications of its bonding. Traditional fuel analyses of this fuel are also provided. These include: ultimate analysis — the elemental composition of the overall fuel C, H, N, S, and O; chlorine analysis — reported here …


Analysis Of Sunflower Shells By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford Dec 2005

Analysis Of Sunflower Shells By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford

Faculty Publications

Determining the chemical structure and composition of biomass fuels using x-ray photoelectron spectroscopy (XPS) can provide fundamental knowledge of their structures that is useful in understanding and predicting their combustion behavior. Sunflower shells are an example of an agricultural residue (byproduct of food and feed production) of potential interest for biomass combustion. The XPS spectra of sunflower shells provide both its elemental composition and indications of its bonding. Traditional fuel analyses of this fuel are also provided. These include: ultimate analysis — the elemental composition of the overall fuel (C, H, N, S, and O); chlorine analysis — reported here …


Research Article| December 30 2005 Analysis Of Shea Nut Shells By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford Dec 2005

Research Article| December 30 2005 Analysis Of Shea Nut Shells By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford

Faculty Publications

Determining the chemical structure and composition of biomass fuels using x-ray photoelectron spectroscopy (XPS) can provide fundamental knowledge of their structures that is useful in understanding and predicting their combustion behavior. Shea nut shells are an example of an agricultural residue (byproduct of food and feed production) of potential interest for biomass combustion. The XPS spectra of shea nut shells provide both its elemental composition and indications of its bonding. Traditional fuel analyses of this fuel are also provided. These include: ultimate analysis — the elemental composition of the overall fuel (C, H, N, S, and O); chlorine analysis — …


Analysis Of Straw By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford Dec 2005

Analysis Of Straw By X-Ray Photoelectron Spectroscopy, Guilin Jiang, Ghaleb A. Husseini, Larry Lin Baxter, Matthew R. Linford

Faculty Publications

Determining the chemical structure and composition of biomass fuels using x-ray photoelectron spectroscopy XPS can provide fundamental knowledge of their structures that is useful in understanding and predicting their combustion behavior. Straw is an example of an agricultural residue byproduct of food and feed production of potential interest for biomass combustion. The XPS spectra of straw provide both its elemental composition and indications of its bonding. Traditional fuel analyses of this fuel are also provided. These include: ultimate analysis — the elemental composition of the overall fuel C, H, N, S, and O; chlorine analysis — reported here as part …


Predicted Redidual Strength Of Damaged Isotrussâ® Structures, Travis S. Carroll Dec 2005

Predicted Redidual Strength Of Damaged Isotrussâ® Structures, Travis S. Carroll

Theses and Dissertations

This thesis utilized a linear analytical approach to explore the damage tolerance or residual strength as a function of increasing damage in traditional single and hybrid-grid IsoTruss® structures. Residual strength was studied for structures subjected to axial compression, torsion and flexural bending, independently. Carbon/epoxy material properties were applied in all load cases, and fiberglass/epoxy material properties were also applied in the flexural bending case. Prior to imposing damage conditions, the IsoTruss® structures were parametrically optimized to achieve the highest strength-to-weight ratios. Typical compression strut, driveshaft, and utility pole specifications governed the design strength dimensions and boundary conditions. Damage growth was …


Fully Compliant Tensural Bistable Micro-Mechanisms (Ftbm), D. L. Wilcox, Larry L. Howell Dec 2005

Fully Compliant Tensural Bistable Micro-Mechanisms (Ftbm), D. L. Wilcox, Larry L. Howell

Faculty Publications

A new class of bistable mechanisms, the fully compliant tensural bistable micromechanism (FTBM) class, is introduced. The class consists of linear bistable micromechanisms that undergo tension loads, in addition to the bending loads present, through their range of motion. Proof-of-concept designs fabricated in two different microelectromechanical systems (MEMS) surface micromachining processes were demonstrated. Three sets of refined designs within the FTBM class were designed using optimization methods linked with nonlinear finite element analysis (FEA), then fabricated and tested. Measured force and displacement performance are compared to values obtained by FEA. On-chip actuation of the bistable mechanisms was achieved using thermomechanical …


Performance Analysis Of Common Detectors For Shaped Offset Qpsk And Feher's Qpsk, Tom Nelson, Michael D. Rice, Erik Perrins Dec 2005

Performance Analysis Of Common Detectors For Shaped Offset Qpsk And Feher's Qpsk, Tom Nelson, Michael D. Rice, Erik Perrins

Faculty Publications

Sponsorship: US Air Force Grant FA9302-05-C-0001. A detector architecture capable of detecting both shaped offset quadrature phase shift keying (SOQPSK-TG) and Feher's quadrature phase shift keying (FQPSK-JR) is developed and analyzed. Both modulations are embodied as fully interoperable modulations in the Interrange Instrumentation Group (IRIG) standard IRIG-106. It is shown that the common detector achieves near optimal bit error rate performance without knowledge of which modulation is used by the transmitter. The detection techniques are based on a common trellis-coded modulation representation and a common continuous phase modulation (CPM) representation for these two modulations. In addition the common pulse amplitude …


Statnamic Lateral Load Testing And Analysis Of A Drilled Shaft In Liquefied Sand, Seth I. Bowles Dec 2005

Statnamic Lateral Load Testing And Analysis Of A Drilled Shaft In Liquefied Sand, Seth I. Bowles

Theses and Dissertations

Three progressively larger statnamic lateral load tests were performed on a 2.59 m diameter drilled shaft foundation after the surrounding soil was liquefied using down-hole explosive charges. An attempt to develop p-y curves from strain data along the pile was made. Due to low quality and lack of strain data, p-y curves along the test shaft could not be reliably determined. Therefore, the statnamic load tests were analyzed using a ten degree-of-freedom model of the pile-soil system to determine the equivalent static load-deflection curve for each test. The equivalent static load-deflection curves had shapes very similar to that obtained from …


A Detailed Approach For Concept Generation And Evaluation In A Technology Push Product Development Environment, Andrew Nelson Dec 2005

A Detailed Approach For Concept Generation And Evaluation In A Technology Push Product Development Environment, Andrew Nelson

Theses and Dissertations

Many companies rely on successful product development as a means to increase their revenues and expand their operations. Market pull, the most common form of product development, begins with a specific customer, and focuses on how to satisfy that customer's needs. Technology push is a product development process where a technology is first discovered, then embodied in products that may be marketed to specific customers. Technology push presents several obstacles not encountered in market pull processes, such as a lack of a defined market, lack of established processes and difficulty in execution. These complications keep technology push from being more …


Modeling Microwave Emissions Of Erg Surfaces In The Sahara Desert, David G. Long, Haroon Stephen Dec 2005

Modeling Microwave Emissions Of Erg Surfaces In The Sahara Desert, David G. Long, Haroon Stephen

Faculty Publications

Sand seas (ergs) of the Sahara are the most dynamic parts of the desert. Aeolian erosion, transportation, and deposition continue to reshape the surface of the ergs. The large-scale features (dunes) of these bedforms reflect the characteristics of the sand and the long-term wind. Radiometric emissions from the ergs have strong dependence on the surface geometry. We model the erg surface as composed of tilted rough facets. Each facet is characterized by a tilt distribution dependent upon the surface roughness of the facet. The radiometric temperature (Tb) of ergs is then the weighted sum of the Tb from all the …


Preliminary Design Approach For Prosthetic Ankle Joints Using Compliant Mechanisms, Jason Matthew Wiersdorf Dec 2005

Preliminary Design Approach For Prosthetic Ankle Joints Using Compliant Mechanisms, Jason Matthew Wiersdorf

Theses and Dissertations

The objective of this thesis is to develop design approaches and models for prosthetic ankle joints using kinematic models of the human ankle and compliant mechanisms technology. Compliant mechanisms offer several potential design advantages over traditional rigid-body designs including high reliability and low cost. These design advantages are ideal for use in prosthetics. Some prosthetic ankle/foot systems currently on the market have multiple degrees of freedom yet are expensive. Additionally, even though these systems have multiple degrees of freedom, none of them are designed after the actual movements of the biological ankle. In this thesis a two, single degree-of-freedom hinge …


An Analysis Of Seawinds-Based Rain Retrieval In Severe Weather Events, David G. Long, Jeffrey R. Allen Dec 2005

An Analysis Of Seawinds-Based Rain Retrieval In Severe Weather Events, David G. Long, Jeffrey R. Allen

Faculty Publications

The Ku-band SeaWinds scatterometer estimates near-surface ocean wind vectors by relating measured backscatter to a geophysical model function for the near-surface vector wind. The conventional wind retrieval algorithm does not explicitly account for SeaWinds' sensitivity to rain, resulting in rain-caused wind retrieval error. A new retrieval method, termed "simultaneous wind/rain retrieval," that estimates both wind and rain from rain-contaminated measurements has been previously proposed and validated with Tropical Rain Measuring Mission data. Here, the accuracy of rains retrieved by the new method is validated through comparison with the Next Generation Weather Radar (NEXRAD) in coastal storm events. The rains detected …


An Investigation Of Employee Satisfaction And Employee Empowerment Specific To On-Site Supervisors In The Residential Construction Industry, David Lars Halvorsen Dec 2005

An Investigation Of Employee Satisfaction And Employee Empowerment Specific To On-Site Supervisors In The Residential Construction Industry, David Lars Halvorsen

Theses and Dissertations

Employee satisfaction and empowerment are vital elements to businesses in most industries. The construction industry has various types of employees, ranging from managers and executives to on-site supervisors and laborers. This study was conducted to obtain a greater understanding about the elements and levels of satisfaction and empowerment of on-site supervisors in the residential construction industry. An on-site supervisor in the residential construction industry is responsible for coordinating and managing employees, materials, equipment, budgets, schedules, contracts, and the safety of employees and the general public. They are also the employees most frequently perceived as accountable for the success or failure …


A New Method For The Rapid Calculation Of Finely-Gridded Reservoir Simulation Pressures, Benjamin Arik Hardy Nov 2005

A New Method For The Rapid Calculation Of Finely-Gridded Reservoir Simulation Pressures, Benjamin Arik Hardy

Theses and Dissertations

A new method for the determination of finely-gridded reservoir simulation pressures has been developed. It is estimated to be as much as hundreds to thousands of times faster than other methods for very large reservoir simulation grids. The method extends the work of Weber et al. Weber demonstrated accuracies for the pressure solution normally requiring millions of cells using traditional finite-difference equations with only hundreds of cells. This was accomplished through the use of finite-difference equations that incorporate the physics of the flow. Although these coarse-grid solutions achieve accuracies normally requiring orders of magnitude more resolution, their coarse resolution does …


Interior Node Projection Techniques In Sweeping Algorithms, Michael Andrew Scott Nov 2005

Interior Node Projection Techniques In Sweeping Algorithms, Michael Andrew Scott

Theses and Dissertations

The enhancement of node projection techniques in sweeping is the subject of this thesis. Sweeping is a method used to produce all-hexahedral finite element meshes on certain classes of geometry. The placement of nodes in the interior of the geometry during the sweeping process remains a difficult problem. This thesis presents advancements in this area which improve the speed of the algorithm and the resulting element quality. A comparison of existing projection methods was performed. The existing Faceted projection sweeping method was extended to be applicable to more general classes of sweepable geometry. This comparison and extension of node projection …


A Gasless Method Of Spraying Thermoplastic Resin, Dan T. Rogers Nov 2005

A Gasless Method Of Spraying Thermoplastic Resin, Dan T. Rogers

Theses and Dissertations

This spraying method for thermoplastic resins is a new manufacturing process for applying thermoplastics to a mold or surface in an efficient way that has the potential of reducing cycle time. Spraying thermoplastic resins is similar to spraying other polymers, such as paint, with the differences being higher pressure and temperature. This method uses an injection molding machine with a modified nozzle to spray the plastic material. In this study, temperature, pressure, and nozzle size were factors that influenced the success of this spraying method. The method of spraying in this study proved spraying without a gas is possible, a …


Object Oriented Cae Software For The Exploration And Design Of Microstructures, Stephen D. Sintay Nov 2005

Object Oriented Cae Software For The Exploration And Design Of Microstructures, Stephen D. Sintay

Theses and Dissertations

Through the use of generalized spherical harmonic basis functions a spectral representation is used to model the microstructure of cubic materials. This model is then used to predict the macroscopic elastic and plastic properties of materials with cubic crystal symmetry and various sample symmetry including triclinic and axial—symmetric. Building on the work of citeN{Barnett-FractureMechanics} the influence that anisotropy has on the fatigue response of the material is also modeled. This is accomplished through using the effective elastic stiffness tensor in the computation of crack extension force G. The resulting material model and macroscopic property calculations are the foundation for …


Recovery Of The Grain Boundary Character Distribution Through Oblique Double-Sectioning, Brent L. Adams, David T. Fullwood, E. R. Homer Nov 2005

Recovery Of The Grain Boundary Character Distribution Through Oblique Double-Sectioning, Brent L. Adams, David T. Fullwood, E. R. Homer

Faculty Publications

This work was supported primarily by the MRSEC program of the National Science Foundation under DMR-0079996. A method for the retrieval of the complete grain boundary character distribution by oblique double-sectioning is proposed. The method, which is similar to the recovery of the orientation distribution from sets of incomplete pole-figures, is efficient and provides many advantages as compared to calibrated serial sectioning. As compared to standard stereological approaches, the new methodology retains the advantage of direct measurement of the grain boundary inclination parameters. Solutions to the fundamental equation of oblique double-sectioning are provided in the Fourier space, and some specifics …


Mpsa Effects On Copper Electrodeposition: Understanding Molecular Behavior At The Electrochemical Interface, Clint Gordon Guymon Nov 2005

Mpsa Effects On Copper Electrodeposition: Understanding Molecular Behavior At The Electrochemical Interface, Clint Gordon Guymon

Theses and Dissertations

In this work the structure of the electrochemical metal-liquid interface is determined through use of quantum mechanics, molecular simulation, and experiment. Herein are profiled the molecular dynamics details and results of solid-liquid interfaces at flat non-specific solid surfaces and copper metal electrodes. Ab initio quantum-mechanical calculations are reported and define the interatomic potentials in the simulations. Some of the quantum-mechanical calculations involve small copper clusters interacting with 3-mercaptopropanesulfonic acid (MPSA), sodium, chloride, bisulfate and cuprous ions. In connection with these I develop the electrode charge dynamics (ECD) routine to treat the charge mobility in a metal. ECD bridges the gap …


Global Finish Curvature Matched Machining, Jianguo Wang Nov 2005

Global Finish Curvature Matched Machining, Jianguo Wang

Theses and Dissertations

As competition grows among manufacturing companies, greater emphasis has recently been placed on product aesthetics and decreasing the product development time. This is promoting and standardizing widespread use of sculptured surface styling within product design. Therefore, industries are looking for high efficiency machining strategies for sculptured surface machining (SSM). Many researchers have produced various methods in tool path generation for SSM. Five-axis curvature matched machining (CM2) is the most efficient. With the widespread use of 5-axis mill in industries, CM2 is a better solution for improving the machining efficiency for product concept models. CM2 has very good performance for global …


A Provacative Test To Determine Brain Compliance In The Management Of Patients With Hydrocephalus, Preston K. Manwaring Nov 2005

A Provacative Test To Determine Brain Compliance In The Management Of Patients With Hydrocephalus, Preston K. Manwaring

Theses and Dissertations

Non-invasive techniques to explore intracranial compliance and pressure have been extensively explored in recent years. Previous techniques have used expensive technologies to make these measurements, often with difficulty. We present a novel, inexpensive provocative test to observe trends in intracranial compliance measurement targeted towards the treatment and management of hydrocephalus. Two techniques are proposed which derive data from the digital and supraorbital arteries as well as tympanic membrane displacement. This requires the use of two photo-plethysmographic sensors and a TMD sensor. A common tilt table apparatus is used to methodically and artificially increase intracranial pressure to stress the cranial system …


Highly Efficient Fluorescence Detection In Picoliter Volume Liquid-Core Waveguides, Aaron R. Hawkins, John P. Barber, Dongliang Yin Nov 2005

Highly Efficient Fluorescence Detection In Picoliter Volume Liquid-Core Waveguides, Aaron R. Hawkins, John P. Barber, Dongliang Yin

Faculty Publications

We report loss improvement and fluorescence detection in integrated antiresonant reflecting optical waveguides with liquid cores. The minimum waveguide loss is reduced to 0.33/cm by compensating for thickness variations in the fabrication process. We demonstrate fluorescence detection from as few as 490 molecules in a 57 pl core using these optimized waveguides. We measure angular fluorescence collection factors as high as 15% per facet in good agreement with theory. This demonstrates the potential of integrated hollow-core waveguides as optical sensors for single-molecule spectroscopy.


Effects Of Reclaimed Asphalt Pavement On Mechanical Properties Of Base Materials, Dane A. Cooley Nov 2005

Effects Of Reclaimed Asphalt Pavement On Mechanical Properties Of Base Materials, Dane A. Cooley

Theses and Dissertations

Reuse of reclaimed asphalt pavement (RAP) in the full-depth recycling (FDR) process is a cost-effective and environmentally responsible method of asphalt pavement reconstruction. Although FDR has been used for several years in some locations, the effect of RAP on the mechanical properties of recycled base materials has not been well documented. The purpose of this research was to investigate the influence of RAP on the mechanical properties of recycled base materials typical of northern Utah. Two sources of RAP, two sources of base, and RAP contents of 0, 25, 50, 75, and 100 percent were utilized in a full-factorial experimental …


High Voltage Analog Design In A Standard Digital Cmos Process, Riley D. Beck Nov 2005

High Voltage Analog Design In A Standard Digital Cmos Process, Riley D. Beck

Theses and Dissertations

This thesis introduces high-voltage approaches that are implemented in an analog Hall-effect sensor interface. This interface has been realized in a modified 5V 0.6um CMOS process using 40V high-voltage MOS transistors that do not affect low-voltage device functionality. These circuits include a high-voltage, low-offset current sense amplifier, which achieves a common-mode input range that is within a Vtp of Vdd using a bulk-driven differential input stage. The amplifier also uses high voltage cascode devices to protect low-voltage devices that have been placed in critical matching areas to achieve a low input offset voltage of 500uV without the use of trim. …


Array Analysis Of Radio Frequency Interference Cancelation Requirements For A Land Mine Detection System, Devin Baker Pratt Nov 2005

Array Analysis Of Radio Frequency Interference Cancelation Requirements For A Land Mine Detection System, Devin Baker Pratt

Theses and Dissertations

Land mines are a major humanitarian problem with millions of active mines in place around the world. Since these mines can have little metal in them, novel detection techniques are needed. Nuclear Quadrupole Resonance (NQR) is one such technique. Unfortunately, NQR is highly succeptible to radio frequency interference (RFI). A significant contribution of this thesis is the development of a custom, experimental data acquisition system designed and built specifically for capturing RFI at frequencies significant to NQR land mine detection systems. Another major contribution is the development of data analysis techniques for determining the number of reference antennas required to …


Development Of Commercial Applications For Recycled Plastics Using Finite Element Analysis, Nanjunda Narasimhamurthy Nov 2005

Development Of Commercial Applications For Recycled Plastics Using Finite Element Analysis, Nanjunda Narasimhamurthy

Theses and Dissertations

This thesis investigates the suitability of thermo-kinetically recycled plastics for use in commercial product applications using finite element analysis and statistics. Different recycled material blends were tested and evaluated for their use in commercial product applications. There are six different blends of thermo-kinetically recycled plastics used for testing and CATIA is used for finite element analysis. The different types of thermo-kinetically recycled plastics blends are: pop bottles made of PolyethyleneTeraphthalate (PET), milk jugs made of High-Density Polyethylene (HDPE), Vinyl seats made of Poly Vinyl Chloride (PVC) and small amount of Polypropylene (PP) and Urethane, electronic scrap made of engineering resins …


Piezoresistive Sensing Of Bistable Micro Mechansim State, Jeffrey K. Anderson Nov 2005

Piezoresistive Sensing Of Bistable Micro Mechansim State, Jeffrey K. Anderson

Theses and Dissertations

The objective of this work is to demonstrate the feasibility of on-chip sensing of bistable mechanism state using the piezoresistive properties of polysilicon, thus eliminating the need for electrical contacts. Changes in position are detected by observing changes in resistance across the mechanism. Sensing the state of bistable mechanisms is critical in their various applications. The research in this thesis advances the modeling techniques of MEMS devices which use piezoresistivity for position sensing. A fully compliant bistable micro mechanism was designed, fabricated, and tested to demonstrate the feasibility of this sensing technique. Testing results from two fabrication processes, Fairchild's SUMMiT …


Evolution Of Turbine Blade Deposits In An Accelerated Deposition Facility: Roughness And Thermal Analysis, James Edward Wammack Nov 2005

Evolution Of Turbine Blade Deposits In An Accelerated Deposition Facility: Roughness And Thermal Analysis, James Edward Wammack

Theses and Dissertations

During the operation of a gas turbine, ingested contaminants present in the air form deposits on the surfaces of the turbine blades. These deposits grow over time, resulting in an increasingly rough surface. This gradual increase in roughness results in several negative consequences, among which is an increase in the rate of heat transfer to the blade which shortens blade life. This thesis presents research in which deposits were evolved on three different turbine blade coupons and their evolution was studied. A trend in roughness change over time was discovered. Also, an attempt was made to find the effect of …