Engineering Commons^™

Small Specimen Test Techniques For Evaluating Radiation-Induced Changes In Mechanical Properties, Ellen Marie Rabenberg

Boise State University Theses and Dissertations

The mechanical properties of as-received and irradiated 304 stainless steel (304SS) were evaluated by the shear punch and miniature tensile techniques. A purpose of this study was to evaluate the shear punch technique itself, which is a less developed technique versus miniature tensile testing. This was accomplished in part by comparing yield and ultimate strengths obtained from shear punch and miniature tensile data. The tests were further correlated by evaluating the mechanical properties of aluminum 6061 and Inconels 600 and 718. A linear relationship was observed between the shear strength and tensile strength data, providing a correlation between the two …

Simulations Of Artificial Neural Network With Memristive Devices, Thanh Thi Thanh Tran

Boise State University Theses and Dissertations

The memristor has been hypothesized to exist as the missing fourth basic circuit element since 1971 [1]. A memristive device is a new type of electrical device that behaves like a resistor, but can change and remember its internal resistance. This behavior makes memristive devices ideal for use as network weights, which will need to be adjusted as the network tries to acquire correct outputs through a learning process. Recent development of physical memristive-like devices has led to an interest in developing artificial neural networks with memristors.

In this thesis, a circuit for a single node network is designed to …

Fabrication Of Solid Solution Tungsten-Rhenium Alloys By High Energy Ball Milling And Spark Plasma Sintering, Cory C. Sparks

Boise State University Theses and Dissertations

Tungsten-rhenium powders of varying compositions were fabricated by spark plasma sintering (SPS). In initial exploration of the parameter space, W-25 at% Re powders were blended and consolidated by SPS at 1500 to 1900°C with sintering dwell times of 0 to 60 minutes. In addition, the influence of milling was investigated. W-25 at% Re powders were high-energy ball milled at 200 to 400 rpm for 5 hours and consolidated at 1700°C with sintering dwell times of 0 to 60 minutes. The sample densities, grain sizes, porosities, contamination level, and hardness values were measured. The intermetallic content, specifically the fraction of σ-phase, …

Testing, Analysis, And Model Verification Of Miniature Linear Permanent Magnet Generators, Michael Ray Rippee

Boise State University Theses and Dissertations

The military has become increasingly dependent on mobile electronic equipment to ensure success and safety of soldiers in remote locations. To operate the electronics, soldiers must carry batteries that can weigh up to 12kg (26.5lb). To decrease the load soldiers must carry, a backpack with an internal linear electric generator has been proposed to provide portable power for soldiers on foot. In designing a generator for this purpose, a simulation was developed to predict the power generation capacity of linear permanent magnet generators. This thesis presents work done to experimentally verify the theoretical simulation with a desired accuracy of 20%. …

Electron Self-Trapping In Ge2 Se3 And Its Role In Ag And Sn Incorporation, Arthur H. Edwards, Kristy A. Campbell, Andrew C. Pineda

Electrical and Computer Engineering Faculty Publications and Presentations

We present a set of density functional theory (DFT) calculations on the electronic structure of Ag and Sn in Ge₂ Se₃ in a periodic model. We show that electron self-trapping is a persistent feature in the presence of many defects. Ag and Sn autoionize upon entering Ge₂ Se₃ becoming Ag₊ and Sn₂₊ , respectively, and the freed electrons self trap at the lowest energy site. Both Ag and Sn can substitute for Ge, and we present formation energies as a function of Fermi level that show that Sn can substantially alter the incorporation of …

Experimental Validation Of A Numerical Forward Model For Tunnel Detection Using Cross-Borehole Radar, Arvin Farid, Jose A. Martinez-Lorenzo, Akram N. Alshawabkeh, Carey M. Rappaport

Civil Engineering Faculty Publications and Presentations

The goal of this research is to develop an experimentally validated twodimensional (2D) finite difference frequency domain (FDFD) numerical forward model to study the potential of radar-based tunnel detection. Tunnel detection has become a subject of interest to the nation due to the use of tunnels by illegal immigrants, smugglers, prisoners, assailants, and terrorists. These concerns call for research to nondestructively detect, localize, and monitor tunnels. Nondestructive detection requires robust image reconstruction and inverse models, which in turn need robust forward models. Cross-Well Radar (CWR) modality is used for experimentation to avoid soil-air interface roughness. CWR is not a versatile …

Analysis Of Electromagnetic Stimulation Of Transport In Water For Geoenvironmental Applications, Mahsa Azad

Boise State University Theses and Dissertations

Air sparging is a popular soil and groundwater remediation technique, which enables the removal of volatile organic compounds (VOCs) through diffusing contaminant-free air into saturated zones of soil. However, the VOC removal process is slow due to the soils' low permeability, and might take months to years depending on the type of the soil and contaminant. The goal of this thesis is to study the effect of electromagnetic (EM) waves —with minimal heat generation— on transport mechanisms such as diffusion, in order to improve airflow and expedite the cleanup process using air sparging or similar technologies. Because water dipole molecules …

Kinetics And Mechanisms Of Titanium Wire Oxidation, Tanmay P. Engineer

Boise State University Theses and Dissertations

The kinetics and mechanisms of oxidation of titanium wire were assessed using a large test matrix in Ar-20% O₂ at 800 to 1200°C, and N₂-20% O₂ at 1000°C, for 0.5 to 24 hours. The effects of geometry on oxidation were evaluated by investigating the behavior of six high purity Ti wires with diameters varying from 50 to 2000 μm, with an objective of producing hollow TiO₂ tubes.

Oxidation behavior was characterized by measuring oxide thicknesses and morphology by optical microscopy, and the phases were characterized using a combination of SEM and TEM. The kinetics was …

Structural And Electronic Properties Of Cs-Doped Sic: A First-Principles Investigation, Tram Bui

Boise State University Theses and Dissertations

The structural and electronic properties of pure and Cs-doped cubic zinc-blende silicon carbide (3C-SiC) were modeled by density functional theory in the plane-wave pseudo-potential formalism as implemented in the Quantum-ESPRESSO package. The equilibrium properties including lattice constant, bulk modulus, cohesive energy, and the indirect band gap energy were calculated for pure 3C-SiC. These values were compared with the experimental and theoretical values reported in the literature, and there was generally excellent agreement.

The influence of Cs on SiC in two structural configurations were modeled, including bulk SiC and a Σ3 grain boundary. The present investigation mainly focused on the neutral …

Recrystallization Kinetics Of 3c Silicon Carbide Implanted With 400 Kev Cesium Ions, Daniel Denell Osterberg

Boise State University Theses and Dissertations

Polycrystalline 3C silicon carbide was implanted at room temperature with 400 keV cesium ions to a dose of 10¹⁶ ions·cm^-2. The samples were then annealed at 600 – 1000°C for 0-48 hours in ultra-high purity argon. The implanted zone of each sample was characterized by transmission electron microscopy and secondary ion mass spectroscopy. It is shown that the implantation resulted in a 217 ± 2 nm amorphous region with microstructural damage extending to approximately 250 nm below the surface. Recrystallization of the amorphous region was observed at 725°C, although minimal densification was observed until ≥ 800°C. Densification …

Extending The Battery-Powered Operating Time Of A Wireless Environmental Monitoring System, Ross Matthew Butler

Boise State University Theses and Dissertations

Advances in low-power microelectronics and sensor technologies have enabled the creation of sophisticated environmental monitoring systems capable of operating on battery power. Independence from a power outlet connection opens up many new potential applications, but limited battery life still imposes significant restrictions on a monitoring system’s capabilities and the number of systems that can be economically deployed and maintained. These restrictions have motivated much research into reducing monitoring system energy usage, increasing battery capacity, and harnessing alternative energy sources. While most of the research focuses on new system design, there is a need for techniques to extend the battery-powered operating …

Joint Estimation Of Channel And Oscillator Phase Noise In Mimo Systems, Hani Mehrpouyan, Ali A. Nasir, Steven D. Blostein, Thomas Eriksson, George K. Karagiannidis, Tommy Svensson

Hani Mehrpouyan

Oscillator phase noise limits the performance of high speed communication systems since it results in time varying channels and rotation of the signal constellation from symbol to symbol. In this paper, joint estimation of channel gains and Wiener phase noise in multi-input multi-output (MIMO) systems is analyzed. The signal model for the estimation problem is outlined in detail and new expressions for the Cramér-Rao lower bounds (CRLBs) for the multi-parameter estimation problem are derived. A data-aided least-squares (LS) estimator for jointly obtaining the channel gains and phase noise parameters is derived. Next, a decision-directed weighted least-squares (WLS) estimator is proposed, …

Design Of Wideband Continuous-Time Δς Adcs Using Two-Step Quantizers, Sakkarapani Balagopal, Vishal Saxena

Electrical and Computer Engineering Faculty Publications and Presentations

Continuous-time delta sigma (CT-ΔΣ) ADCs are established as the data conversion architecture of choice for the next-generation wireless applications. Several efforts have been made to simultaneously improve the bandwidth and dynamic range of ΔΣ ADCs. We proposed using two-step quantizer in a single-loop CT-ΔΣ modulator to achieve higher conversion bandwidth. This paper presents a tutorial for employing the design technique through a 130n CMOS implementation. The proposed 640 MS/s, 4^th order continuous-time delta sigma modulator (CT-ΔΣM) incorporates a two-step 5-bit quantizer, consisting of only 13 comparators. The CT-ΔΣM achieves a dynamic range of 70 dB, peak SNDR of 65.3 …

A 1 Gs/S, 31 Mhz Bw, 76.3 Db Dynamic Range, 34 Mw Ct-Δς Adc With 1.5 Cycle Quantizer Delay And Improved Stf, Sakkarapani Balagopal, Vishal Saxena

Electrical and Computer Engineering Faculty Publications and Presentations

A 1 GS/s Continuous-time Delta-Sigma modulator (CT-ΔΣM) with 31 MHz bandwidth, 76.3 dB dynamic range and 72.5 dB signal-to-noise is reported in a 0.13μm CMOS technology. The design employs an excess loop delay (ELD) of more than one clock cycle for achieving higher sampling rate. The ELD is compensated using a fast-loop formed around the last integrator by using a sample-and-hold. Further, the effect of this ELD compensation scheme on the signal transfer function (STF) of a feedforward CT-ΔΣ architecture has been analyzed and reported. In this work, an improved STF is achieved by using a combination of feed-forward, feed-back …

Gpu-Accelerated Modeling Of Microscale Atmospheric Flows Over Complex Terrain, Anthony Rey Deleon

Boise State University Theses and Dissertations

With installed wind power capacities steadily on the rise, balancing the loads on electrical grids is challenging due to the intermittency of the wind. Short-term wind power forecasting can be a valuable tool for better informing grid operators on the available wind power. Current short-term wind forecasting techniques typically adopt mesoscale weather forecasting models with spatial resolutions on the order of a kilometer. On relatively flat terrain, use of mesoscale models may prove effective, but application to complex terrain induces large forecasting errors. To address this issue, a baseline incompressible flow solver for GPU (graphics processing unit) clusters is extended …

Cmos Characterization, Modeling, And Circuit Design In The Presence Of Random Local Variation, Benjamin A. Millemon Sr.

Boise State University Theses and Dissertations

Random local variation in CMOS transistors complicates characterization procedures, modeling efforts, simulation tools, and circuit design methodologies in highly scaled CMOS devices. Mismatch is not only a concern for closely matched device pairs in analog circuits; digital circuit designers also have to consider the effects of random variation. Device characterization, modeling, process development, and circuit design engineers have to work together to mitigate the impact of random local variation. This thesis outlines the primary challenges of CMOS characterization, modeling, and circuit design in the presence of random local variation and offers guidelines and solutions to help mitigate and model the …

Training Professionals’ Usage And Understanding Of Kirkpatrick’S Level 3 And Level 4 Evaluations, Perri Estes Kennedy

Boise State University Theses and Dissertations

Behavior-based (Level 3) and results-based (Level 4) evaluations of training interventions can provide organizations with substantive proof of the value of those interventions. Training professionals have long acknowledged the necessity of conducting such evaluations, yet Level 3 evaluations are conducted for only about half of all training interventions and Level 4 for about one-third. This research examined the frequency with which training professionals currently conduct Level 3 and Level 4 evaluations, their perceptions on the utility of Level 3 and Level 4 evaluations, and the factors that facilitate or obstruct their attempts to perform such evaluations.

The research was conducted …

Investigations Of Conduction Mechanisms Of Ion-Conducting, Bridging Memory Devices (Cbram/Pmc/Ecm), Kyle Bradley Campbell

Boise State University Theses and Dissertations

Electron storage memory devices are approaching the minimum dimensions that are physically possible due to the onward march of Moore’s law. To continue to enable the increased memory densities needed for today’s applications, especially low power and size constrained mobile devices, new memory solutions are needed. Several candidates are emerging in this space. Metal ion-conducting memory devices are being investigated due to excellent scalability, speed, and low power. These devices are part of a memory class called resistive memory. In the literature, they are referred to as CBRAM (conductive bridge random access memory), PMC (programmable metallization cell), ECM (electrochemical metallization …

A Low-Power Single-Bit Continuous-Time Δς Converter With 92.5 Db Dynamic Range For Biomedical Applications, Sakkarapani Balagopal, Vishal Saxena

Electrical and Computer Engineering Faculty Publications and Presentations

A third-order single-bit CT-ΔΣ modulator for generic biomedical applications is implemented in a 0.15 µm FDSOI CMOS process. The overall power efficiency is attained by employing a single-bit ΔΣ and a subthreshold FDSOI process. The loop-filter coefficients are determined using a systematic design centering approach by accounting for the integrator non-idealities. The single-bit CT-ΔΣ modulator consumes 110 µW power from a 1.5 V power supply when clocked at 6.144 MHz. The simulation results for the modulator exhibit a dynamic range of 94.4 dB and peak SNDR of 92.4 dB for 6 kHz signal bandwidth. The figure of merit (FoM) for …

Monitoring Of The Aircraft Cabin Environment Via A Wireless Sensor Network, Michael Pook, Sin Ming Loo, Joshua Kiepert

Electrical and Computer Engineering Faculty Publications and Presentations

Wireless sensor networks consist of physically distributed autonomous sensor nodes that cooperatively monitor physical or environmental conditions. The key benefit of wireless sensor networks is that they are capable of generating a more complete view of the sensed environment by acquiring larger quantities of correlated data than independent sensor monitors. This makes them ideally suited for applications where a complex environment with many interdependent factors must be monitored. The aircraft cabin is one such example of a highly dynamic environment which necessitates the use of an advanced sensing system. Thus, in order to gain a better understanding of the aircraft …

A Portable Wireless Particulate Sensor System For Continuous Real-Time Environmental Monitoring, James A. Hall Jr., Sin Ming Loo, Dale Stephenson, Ross Butler, Michael Pook, Joshua Kiepert, Jordan Anderson, Nicholas Terrell

Electrical and Computer Engineering Faculty Publications and Presentations

Airborne particulate matter has been shown to be associated with morbidity and mortality, and may interfere with certain sensitive experiment. Understanding the levels and movements of particulate matter in an enclosed space can lead to a reduction in the impact of this material on health and experimental results. A system of environmental sensors including particulate matter, selected gasses, humidity, temperature, and pressure can be used to assist in tracking air movement, providing real-time mapping of potential contaminants as they move through a space. In this paper we present a system that is capable of sensing these environmental factors, collecting data …

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 …

Kinematic And Kinetic Synergies Of The Lower Extremities During The Pull In Olympic Weightlifting, Kristof Kipp, Josh Redden, Michelle Sabick, Chad Harris

Mechanical and Biomedical Engineering Faculty Publications and Presentations

The purpose of this study was to identify multijoint lower extremity kinematic and kinetic synergies in weightlifting and compare these synergies between joints and across different external loads. Subjects completed sets of the clean exercise at loads equal to 65, 75, and 85% of their estimated 1-RM. Functional data analysis was used to extract principal component functions (PCF's) for hip, knee, and ankle joint angles and moments of force during the pull phase of the clean at all loads. The PCF scores were then compared between joints and across loads to determine how much of each PCF was present at …

What Value Does Service Learning Have On Introductory Engineering Students' Motivation And Abet Program Outcomes?, Carol Sevier, Seung Youn Chyung, Janet Callahan, Cheryl Schrader

Organizational Performance and Workplace Learning Faculty Publications and Presentations

A quasi-experimental study was conducted to investigate the effectiveness of using a service learning (SL) method on influencing introductory engineering students' motivation and ABET program outcomes, compared to the effectiveness of using a conventional, non-service-learning (NSL) method. The sample used in the study was 214 students enrolled in an Introduction to Engineering course at a medium-size university in the northwestern region of the U.S. during the fall semester of 2009 and the spring semester of 2010. Sixty-nine students completed SL projects while 145 students completed NSL projects. Both SL and NSL projects were team-based. Using the ARCS model as a …

Weightlifting Performance Is Related To Kinematic And Kinetic Patterns Of The Hip And Knee Joints, Kristof Kipp, Josh Redden, Michelle B. Sabick, Chad Harris

Mechanical and Biomedical Engineering Faculty Publications and Presentations

The purpose of this study was to investigate correlations between biomechanical outcome measures and weightlifting performance. Joint kinematics and kinetics of the hip, knee, and ankle were calculated while ten subjects performed a clean at 85% of 1-RM. Kinematic and kinetic time-series patterns were extracted with principal components analysis. Discrete scores for each time-series pattern were calculated and used to determine how each pattern was related to body-mass normalized 1-RM. Two hip kinematic and two knee kinetic patterns were significantly correlated with relative 1-RM. The kinematic patterns captured hip and trunk motions during the first pull and hip joint motion …

How Rapidly Should Developing Countries Implement Intelligent Transportation Systems (Its) To Solve The Growing Urban Traffic Congestion Problem?, Mandar Khanal

Civil Engineering Faculty Publications and Presentations

Many newly developing countries are growing rapidly. One example is India, currently the second most populous country in the world. According to the Indian Ministry of Urban Development, from 1981 to 2001, the population in six major Indian cities increased twofold while motor vehicles increased eightfold. Such rapid growth in vehicles without a comparable growth in transportation infrastructure leads to increasing traffic congestion. Cities in India are already considered congested today, and are going to be even more congested in the coming years since the rate of urbanization in India in 2006 was only 29% and is expected to grow …

Effect Of Fluxing Additive On Sintering Temperature, Microstructure And Properties Of Batio3, Yaseen Iqbal, Asad Jamal, Riaz Ullah, M. Naeem Khan, Rick Ubic

Materials Science and Engineering Faculty Publications and Presentations

Various fluxing materials are added to technical ceramics in an attempt to lower their sintering temperatures and make their processing economical. The effect of 0·3wt% Li₂CO₃ addition on the phase, microstructure, phase transition temperatures and dielectric properties of BaTiO₃ was investigated in the present study. The addition of 0·3wt% Li2CO₃ was observed to lower the optimum sintering temperature by ∼200^◦C with no second phase formation and cause a five-fold reduction in grain size. Rhombohedral-to-orthorhombic and tetragonal-to-cubic phase transitions at the expected temperatures were evident from the Raman spectra, but the orthorhombic-totetragonal phase transition …

Near Surface Hydrometeorology For Sustainable Water Management, V. Sridhar, W. T. A. Jaksa

Civil Engineering Faculty Publications and Presentations

Due to strong interactions between the land and atmosphere and the resulting feedbacks as altered by the anthropogenic changes, it is critical to quantify the surface fluxes and boundary layer properties that has direct implications on the regional evolution of hydrometeorology. This study evaluates the impact of irrigation using the Weather Research and Forecasting (WRF) numerical weather prediction (NWP) model in the Snake River Basin in Idaho. Our simulation extends for the period in the growing season and compares the control and irrigation runs to assess the irrigation induced cooling on the surface energy balance. Understanding this near surface cooling …

Biomedical Matching Gui Development, Nazia Sarang

Electrical and Computer Engineering Graduate Theses and Dissertations

Biomedical researchers constantly search for new methods to diagnose the extent of joint injuries in live human subjects. In order to achieve this, the researchers need to know the accurate three dimensional kinematic data of bones and joints and to accurately quantify how bones in a joint move relative to one another during dynamic activities. Algorithms have been developed previously to estimate the exact spatial position and movement of the bones. These methods involved generation of digitally reconstructed radiographs (DRR) from a three dimensional CT scan image of human joint with known position and orientation and comparing it with the …

Investigation Of The Current Transmission Hysteresis In Electron Hop Funnels, Marcus Pearlman

Boise State University Theses and Dissertations

To integrate field emitter arrays (FEAs) into microwave vacuum electron devices, the use of insulating funnels, called electron hop funnels, is proposed. Electrons are emitted into the wide end of the funnel, and utilizing secondary electron emission to sustain current, the electrons "hop" up the funnel walls. Eventually the electrons exit the funnel as a denser and more uniform electron beam. To pull the electrons up the funnel, an electrode, called the hop electrode, is placed around the exit of the funnel to generate an electric field between the funnel exit and the electron source. The current transmitted through the …