Engineering Commons^™

Managing Hydrologic Data, Observations And Terrain Analysis, David G. Tarboton

Civil and Environmental Engineering Faculty Publications

No abstract provided.

Dual-Frequency Phase Multiplexing (Dfpm) And Period Coded Phase Measuring (Pcpm) Pattern Strategies In 3-D Structured Light Systems, And Lookup Table (Lut) Based Data Processing, Kai Liu, Yongchang Wang, Daniel L. Lau, Laurence G. Hassebrook

Electrical and Computer Engineering Faculty Patents

A computer-implemented process, system, and computer-readable storage medium having stored thereon, program code and instructions for 3-D triangulation-based image acquisition of a contoured surface/object-of-interest under observation by at least one camera . . .

For the remainder of this abstract, please download this patent.

Entanglement Dynamics Of One-Dimensional Driven Spin Systems In Time-Varying Magnetic Fields, Bedoor Alkurtass, Gehad Sadiek, Sabre Kais

Birck and NCN Publications

We study the dynamics of nearest-neighbor entanglement for a one-dimensional spin chain with a nearest-neighbor time-dependent Heisenberg coupling J(t) between the spins in the presence of a time-dependent external magnetic field h(t) at zero and finite temperatures. We consider different forms of time dependence for the coupling and magnetic field: exponential, hyperbolic, and periodic. Solving the system numerically, we examined the system-size effect on the entanglement asymptotic value. It was found that, for a small system size, the entanglement starts to fluctuate within a short period of time after applying the time-dependent coupling. The period of time increases as the …

Special Issue On The 6th International Phytotechnologies Conference, St. Louis, Missouri, 2009: Conference Review, Joel G. (Gerard) Burken, Jason C. White

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

Collaborative Products: A Design Methodology With Application To Engineering-Based Poverty Alleviation, Jacob S. Morrise

Theses and Dissertations

Collaborative products are created when physical components from two or more products are temporarily recombined to form another product capable of performing entirely new tasks. The method for designing collaborative products is useful in developing products with reduced cost, weight, and size. These reductions are valued in the developing world because collaborative products have a favorable task-per-cost ratio. In this paper, a method for designing collaborative products is introduced. The method identifies a set of products capable of being recombined into a collaborative product. These products are then designed to allow for this recombination. Three examples are provided to illustrate …

In Situ Synthesis Of Ultrafine Ss-Mno2/Polypyrrole Nanorod Composites For High-Performance Supercapacitors, Jianfeng Zang, Xiaodong Li

Faculty Publications

We report a remarkable observation that is at odds with the established notion that β-MnO₂ was regarded as an undesirable candidate for supercapacitor applications. The specific capacitance of β-MnO₂ can reach as high as 294 F g⁻¹, which is comparable to the best crystallographic structure, like α-MnO₂. The key is to substantially decrease the size of β-MnO₂ powders to ultra small regime. We demonstrate a facile, simple, and effective approach to synthesizing ultrafine (<10 nm in diameter) β-MnO₂/polypyrrole nanorod composite powders for high-performance supercapacitor electrodes. Our observation may encourage a revisit of the other good …

Characteristics Of The Hydrogen Electrode In High Temperature Steam Electrolysis Process, Chao Jin, Chenghao Yang, Fanglin Chen

Faculty Publications

YSZ-electrolyte supported solid oxide electrolyzer cells (SOECs) using LSM-YSZ oxygen electrode but with three types of hydrogen electrode, Ni–SDC, Ni–YSZ and LSCM–YSZ have been fabricated and characterized under different steam contents in the feeding gas at 850°C. Electrochemical impedance spectra results show that cell resistances increase with the increase in steam concentrations under both open circuit voltage and electrolysis conditions, suggesting that electrolysis reaction becomes more difficult in high steam content. Pt reference electrode was applied to evaluate the contributions of the hydrogen electrode and oxygen electrode in the electrolysis process. Electrochemical impedance spectra and over potential of both electrodes …

A New Undergraduate Laboratory Course In Magnetic Design, Taufik Taufik, Scott Mcclusky, Jonathon Paolucci, Dale S. Dolan

Electrical Engineering

This paper presents a set of new laboratory experiments developed in conjunction with an undergraduate course in magnetic design. The course has recently been reintroduced as a technical elective course where students learn the basics of inductor and transformer design. Five new laboratory experiments have been developed to cover magnetic concepts and to provide students with the hands-on experience in designing and building magnetic components. The paper presents an overview of the course, and highlights the new lab experiments in the course.

Development Of Wind Tunnel For Laboratory Wind Turbine Testing, Dale S. Dolan, Danny Zepeda, Taufik Taufik

Electrical Engineering

This paper presents the development of a wind tunnel that will be used for wind turbine testing in a controlled environment. The prototype is designed to be able to provide wind speeds of up to 20 m/s (~43mph) depending on the cross sectional area of the tunnel chamber. A 42 inch tube axial fan is driven by a 5hp induction motor using a variable frequency drive to allow continuously variable wind speeds from near zero up to the maximum wind speed. The fan is rated to produce ~25,000 CFM and the corresponding wind speed is therefore dependent on chamber cross …

The Effect Of Tool Rotation Speed And Clamping On Deformation In Friction Stir Welded 6061-T6511 Aluminum Extrusions, Travis Lee Smith

LSU New Orleans Theses and Dissertations

Friction Stir Welding (FSW) was used to perform Bead on Plate (BOP) welds on 6061-T6511 aluminum extrusions. Using a DOE approach, tool rotation speed, clamp spacing, and clamping force were altered to ascertain their effects on distortion in the welded panels. Mechanical forces were monitored during the weld process. Both linear and out of plane distortion were measured on the welded extrusions. The Vickers hardness of the weld nugget was measured. The effect of each parameter on weld distortion was discovered and the mechanism of this link was suggested.

A Study On Remaining Useful Life Prediction For Prognostic Applications, Gang Liu

LSU New Orleans Theses and Dissertations

We consider the prediction algorithm and performance evaluation for prognostics and health management (PHM) problems, especially the prediction of remaining useful life (RUL) for the milling machine cutter and lithium ‐

ion battery. We modeled battery as a voltage source and internal resisters. By analyzing voltage change trend during discharge, we made the prediction of battery remain discharge time in one discharge cycle. By analyzing internal resistance change trend during multiple cycles, we were able to predict the battery remaining useful time during its life time. We showed that the battery rest profile is correlated with the RUL. Numerical results …

Ceas E-News 08.03.2011, College Of Engineering And Applied Sciences

College of Engineering and Applied Sciences News

BTR Bike Race, Sunseeker Events

An Investigation Of Concrete Properties In Support Of International Testing Standards, Justine Barnes

Symposium on Research and Creative Expression (SORCE)

Fresh and hardened concrete testing is an important aspect in evaluating the quality of ready mixed concrete. The testing process requires many standards to ensure repeatable results. The research being conducted examines two particular standards ASTM C143-The Slump of Hydraulic Concrete and ASTM 496-Split Tension Testing of Hardened Concrete. The first test compares the slump on a flat and level surface with the slump when tested on a surface which slopes up to 8%. For each batch of concrete created, 30 slump tests are conducted and three 4x8 cylinders were created for compression testing. The second test examines whether the …

Carotid Plaque Regression Following 6-Month Statin Therapy Assessed By 3t Cardiovascular Magnetic Resonance: Comparison With Ultrasound Intima Media Thickness, Raymond Q. Migrino, Mark Bowers, Leanne Harmann, Robert W. Prost, John F. Ladisa

Biomedical Engineering Faculty Research and Publications

Background

Cardiovascular magnetic resonance (CMR) allows volumetric carotid plaque measurement that has advantage over 2-dimensional ultrasound (US) intima-media thickness (IMT) in evaluating treatment response. We tested the hypothesis that 6-month statin treatment in patients with carotid plaque will lead to plaque regression when measured by 3 Tesla CMR but not by IMT.

Methods

Twenty-six subjects (67 ± 2 years, 7 females) with known carotid plaque (> 1.1 mm) and coronary or cerebrovascular atherosclerotic disease underwent 3T CMR (T1, T2, proton density and time of flight sequences) and US at baseline and following 6 months of statin therapy (6 had initiation, …

Guidelines For Constructing Climate Scenarios, Philip Mote, Levi D. Brekke, Philip B. Duffy, Edwin P. Maurer

Civil, Environmental and Sustainable Engineering

Scientists and others from academia, government, and the private sector increasingly are using climate model outputs in research and decision support. For the most recent assessment report of the Intergovernmental Panel on Climate Change, 18 global modeling centers contributed outputs from hundreds of simulations, coordinated through the Coupled Model Intercomparison Project Phase 3 (CMIP3), to the archive at the Program for Climate Model Diagnostics and Intercomparison (PCMDI; http://pcmdi3.llnl.gov) [Meehl et al., 2007]. Many users of climate model outputs prefer downscaled data—i.e., data at higher spatial resolution—to direct global climate model (GCM) outputs; downscaling can be statistical [e.g., Meehl et al., …

The Time Machine: A Novel Spike-Based Computation Architecture, Vaibhav Garg, Ravi Shekhar, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

A novel spike-based computation architecture has been developed which represents synaptic weights in time. An analog chip with 32 neurons, 1024 synapses and an AER block has been fabricated in 0.5μm technology. A digital implementation of the architecture having 6,144 neurons and 100,352 synapses on an FPGA is also described. A digital controller for routing spikes can processes up to 34 million synapses per second. The architecture is called the time machine as it operates on timing events and uses time to store weights. The time machine is general enough for implementing many spike-based algorithms yet provides flexibility and configurability. …

Integrate And Fire Circuit As An Adc Replacement, Manu Rastogi, Alexander Singh Alvarado, John G. Harris, José C. Principe

Electrical and Computer Engineering Faculty Research & Creative Works

We evaluate the performance of an asynchronous analog-to-digital converter known as the Integrate and Fire (I&F) circuit. The reconstruction algorithm for the sampler is presented along with the analytical results for the signal-to-noise ratio (SNR) of the reconstructed signal. We present the power vs. SNR tradeoff, based on the measurements from the chip fabricated in AMI 0.6 m technology. The figure-of-merit (FOM) of the I&F sampler is 0.6 pJ/conversion, which is comparable to the reported FOM for other synchronous and asynchronous ADCs, even though the I&F is implemented in a much older technology as compared to the other ADCs. © …

A Microfiber Cavity With Minimal-Volume Confinement, Ming Ding, Pengfei Wang, Timothy Lee, Gilberto Brambilla

Articles

We demonstrate a type of microcavity with minimal-volume confinement using a high-contrast phase-shifted Bragg grating in a microfiber. While waveguiding by the air-silica boundary provides a diffraction-limited two-dimensional confinement, the grating introduces the third degree of confinement. Theoretical simulations verified the microfiber cavity confinement while the experimental demonstration, carried out in samples nanostructured by focused ion beam, showed a good agreement with theoretical predictions. This cavity can be used for a variety of applications ranging from sensing to quantum dynamic experiments.

Electrochemical Synthesis Of Single Crystal Metal Nanowires, Nan Li

Master's Theses

Electrodeposition is an efficient and economical approach for template synthesis of one-dimensional (1D) nanostructured materials. Based on the porous membranes as templates during electrodeposition, metallic nanowires, nanorods, and nanotubes can overcome the geometrical restrictions to be inserted into the nanometric recesses with both diameter and length well controlled by tuning the size and thickness of the templates.

In this work, the morphology, growth rate and texture of copper nanowires prepared with templates were investigated by the controlled parameters in various experiments. Cu nanowire arrays with preferential orientations can be successfully synthesized into the Anodic Aluminum Oxide (AAO) templates with optimized …

Process-Variation-Aware Electromagnetic-Semiconductor Coupled Simulation, Yuanzhe Xu, Quan Chen, Lijun Jiang, Ngai Wong

Electrical and Computer Engineering Faculty Research & Creative Works

We develop a new method based on the high-frequency electromagnetic (EM)-semiconductor coupled simulation to analyze the impact of multi-type process variations happen around semi-conductormetal structure. It is competent to simultaneously handle geometrical variations like surface roughness and material variations like semi-conductor doping profile, which are difficult for traditional stand alone simulation methods. A sparse grid based stochastic spectral collocation method (SSCM) combined with principle factor analysis (PFA) is implemented to accelerate the stochastic simulation. Numerical results confirm the validity and significance of our variational coupled simulation framework. © 2011 IEEE.

The Integrate-And-Fire Sampler: A Special Type Of Asynchronous ∑-Δ Modulator, Alexander Singh Alvarado, Manu Rastogi, John G. Harris, Jose C. Principe

Electrical and Computer Engineering Faculty Research & Creative Works

We present the integrate-and-fire (IF) model as a time encoding scheme and show that it corresponds to a special case of the asynchronous - modulator (ASDM). We depart from typical rate-based encoding used by conventional ASDM towards time-based encoding. We show that for certain families of signals, such as neural recordings, the IF sampler accurately encodes the regions of interest at sub-Nyquist data rates. Nevertheless, the encoder requires nonlinear recovery algorithms, instead of the typical low pass filter. © 2011 IEEE.

Transcriptional Analysis Of Lactobacillus Brevis To N-Butanol And Ferulic Acid Responses, James Winkler, Katy Kao

Faculty Publications

BackgroundThe presence of anti-microbial phenolic compounds, such as the model compound ferulic acid, in biomass hydrolysates pose significant challenges to the widespread use of biomass in conjunction with whole cell biocatalysis or fermentation. Currently, these inhibitory compounds must be removed through additional downstream processing or sufficiently diluted to create environments suitable for most industrially important microbial strains. Simultaneously, product toxicity must also be overcome to allow for efficient production of next generation biofuels such as n-butanol, isopropanol, and others from these low cost feedstocks.Methodology and Principal FindingsThis study explores the high ferulic acid and n-butanol tolerance in Lactobacillus brevis, a …

Forward Osmosis Bag: Ground Testing The Prospect Of Using Alternative Water Sources For Drinking Water, Michaela Marie Brant, Ariella Yendler, Mona Hammoudeh, Michael T. Flynn

STAR Program Research Presentations

On the STS-135 Space Shuttle mission, to be launched July 8, 2011, a forward osmosis bag (FOB) study will be conducted. At NASA Ames this summer, the ground truth testing is being conducted for results comparisons. The FOB technology is derived from a commercial product, the X-Pack water filter. Forward osmosis operates by utilizing an established concentration gradient across a semi-permeable membrane to move water molecules from one side of the membrane to the other. This concept is exploited to harvest drinking water from grey water sources such as urine, sea water, or vehicle water. In this experiment, potassium chloride …

Assessing Laser Lifetime Test Performance, Joe Weichman, Hamid Hemmati, Malcolm Wright

STAR Program Research Presentations

Assessing expected component lifetime is necessary in developing instruments for future space-flight projects to ensure long term operation in the challenging environment. Although semiconductor diode lasers have widespread use in terrestrial applications, their use in space is still an emerging technology that requires on-going testing to demonstrate their capability. The project called for re-establishing the test setup for assessing lifetime performance of 20 continuously running 200mW 830 nm diode lasers. These lasers underwent previous testing based on parameters for NuSTAR’s laser metrology system, and met the six month lifetime project requirements under nominal operating conditions. Laser testing is currently underway …

Sitting In The Pilot's Seat: Optimizing Human-Systems Interfaces For Unmanned Aerial Vehicles, Steven Michael Queen, Kurt Sanner

STAR Program Research Presentations

One of the pilot-machine interfaces (the forward viewing camera display) for an Unmanned Aerial Vehicle called the DROID (Dryden Remotely Operated Integrated Drone) will be analyzed for optimization. The goal is to create a visual display for the pilot that as closely resembles an out-the-window view as possible. There are currently no standard guidlines for designing pilot-machine interfaces for UAVs. Typically, UAV camera views have a narrow field, which limits the situational awareness (SA) of the pilot. Also, at this time, pilot-UAV interfaces often use displays that have a diagonal length of about 20". Using a small display may result …

Design, Fabrication, And Characterization Of A Thin-Film Nickel-Titanium Shape Memory Alloy Diaphragm For Use In Micro-Electro-Mechanical Systems, Brian Joel Alvarez

Master's Theses

Previous work done at Cal Poly has shown that thin-film nickel-titanium (NiTi) can be easily sputtered onto silicon wafers and annealed to create a crystallized shape memory alloy (SMA) film. Initial work on creating devices yielded cantilevers that were highly warped due to thin-film stress created during the sputtering process. The objective of this work was to create a thin-film NiTi SMA device that could be better characterized. A membrane was selected due to the simplicity of fabrication and testing which would also oppose the thin-film stress due to the increase in attachment points to the substrate.

Silicon wafers were …

Constitutive Model For Rate Dependent Behavior Of Clay Internal Geotechnical Report 2011-3, Harry Martindale, Dipanjan Basu

Technical Reports

This report presents a strain-rate dependent plastic constitutive model for clays. Based on the concepts of critical-state soil mechanics and bounding surface plasticity theory, the model reproduces the mechanical response of clays under multi-axial loading conditions and predicts both the drained and undrained behavior. The model parameters are determined for Boston Blue Clay, London Clay and Kaolin Clay, and the performance of the model in simulating the mechanical response of these clays is demonstrated for low to medium strain rates. The sensitivity of each model parameter is checked by perturbing the calibrated values by ±20%. Subsequently, a probabilistic analysis using …

A High Strain-Rate Constitutive Model For Sand With Application In Finite Element Analysis Internal Geotechnical Report 2011-4, William Higgins, Dipanjan Basu

Technical Reports

The report presents a constitutive model for simulating the high strain-rate behavior of sands. Based on the concepts of critical-state soil mechanics, the bounding surface plasticity theory and the overstress theory of viscoplasticity, the constitutive model simulates the high strain-rate behavior of sands under uniaxial, triaxial and multiaxial loading conditions. The model parameters are determined for Ottawa and Fontainebleau sands, and the performance of the model under extreme transient loading conditions is demonstrated through simulations of split Hopkinson pressure bar tests up to a strain rate of 2000/sec. The constitutive model is implemented in a finite element analysis software to …

Flight Physician - August, 2011, Civil Aviation Medical Association

Browse all Civil Aviation Medical Association Newsletters

A sixteen page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.

Extracting Forensic Artifacts From Windows O/S Memory, James S. Okolica, Gilbert L. Peterson

AFIT Documents

Memory analysis is a rapidly growing area in both digital forensics and cyber situational awareness (SA). Memory provides the most accurate snapshot of what is occurring on a computer at a moment in time. By combining it with event and network logs as well as the files present on the filesystem, an analyst can re-create much of what has occurred and is occuring on a computer. The Compiled Memory Analysis Tool (CMAT) takes either a disk image of memory from a Windows operating system or an interface into a virtual machine running a Windows operating system and extracts forensic artifacts …