Engineering Commons^™

Effect Of Vanadium On Subcritical Heat Treatment Behavior Of Hypoeutectic 16 Wt% Cr Cast Iron Containing 2 Wt% Mo, R Junsamoot, S Inthidech, K Sriprateep, P Sricharoenchai, Y Matsubara

Journal of Metals, Materials and Minerals

Subcritical heat treatment of austenite in alloyed cast iron by tempering at the temperature below pearlite transformation (A1), has been used to improve matrix hardness without hardening. Hypoeutectic high chromium cast irons containing 16 wt% Cr - 2 wt% Mo without and with V were prepared in order to clarify the effect of holding temperature and holding time on behavior of hardness and decomposition fraction of austenite in matrix (f) in subcritical heat treatment. As-cast specimens were held at temperature from 723 K to 923 K for 14.4 - 43.2 ks, and then cooled by fan air. In the as-cast …

Ni Electroless Plating Of Abs Polymer By Palladium And Tin-Free Process, P Dechasit, W Trakarnpruk

Journal of Metals, Materials and Minerals

A palladium and tin-free process for the Ni electroless plating of acrylonitrile-butadiene-styrene (ABS) polymer has been developed. The ABS was first etched then activated with Ni (or Co) ions. Ni or Co adsorbed was quantified by atomic absorption spectroscopy. Sodium borohydride solution was found to be effective in reduction of Ni (or Co) ions. By immersing in a Ni plating bath the Co (or Ni) can then auto-catalytically deposit a Ni film on the ABS. The amount and thickness of Ni film determined by SEM-EDX were the highest when using 3 g/L of nickel acetate solution, 0.5 M sodium borohydride …

Multi-Properties Of Chitosan/Montmorillonite Composite Films Incorporated With Virgin And Modified Montmorillonite, S Kittinaovarat, W Nitayaphat, N Jiratumnukul, S Charuchinda

Journal of Metals, Materials and Minerals

Chitosan (CTS) composite films were prepared by blending CTS with virgin or modified montmorillonite (vMMT or mMMT, respectively) and then spin coating. XRD analysis showed a good intercalation of CTS and the mMMT in the depolymerized 15 kDa CTS/mMMT composite. The tensile strength and rigidity of the CTS/vMMT and CTS/mMMT composite films increased, whilst the elongation at break decreased, with increasing levels of vMMT or, especially, mMMT from 0.1 to 2% (w/w). Both types of CTS/MMT composite films displayed a decreased oil and water absorption with increasing levels of incorporated vMMT or mMMT. Some aggregation of vMMT but not mMMT …

Recovery Of Zinc From The Spent Zinc-Carbon Dry Cell Batteries Through Pyrometallurgical Route, M Haque Khan, Asw Kurny

Journal of Metals, Materials and Minerals

Spent zinc-carbon batteries of all the five types (AAA, AA, C, D and 9V) were processed to recover zinc metal. All the components of the battery were separated, chemically analyzed and the anodic zinc parts were subjected to pyrometallurgical processing. Extraction of zinc was negligible when no fluxing agent was used. However, extent of recovery increased significantly when chloride salts: sodium chloride, calcium chloride and ammonium chloride were used as a fluxing agent. Among these, ammonium chloride gave the best result as flux. Using 10 %wt. of each flux, extraction of zinc was 90% for ammonium chloride, and around 75% …

Preparation Of Copper Lead Frame By Powder Metallurgy Technique, P Y. Chew, A H. You, T R. Vijayaram, B K. See, P S. Lim, M C. Ng

Journal of Metals, Materials and Minerals

Pure Cu is prepared with the dimension of 17.7 mm in diameter and 10 - 15 mm in height using powder metallurgical method to characterize its electrical and mechanical properties. These samples are compacted at a constant pressure of 280 MPa. Pure Cu pellets are sintered at 600C and 950C for 3, 4 and 7 hours. Before sintering, pure Cu pellet is subjected to SEM in order to check the compactness of the pellet, and also the grain structure of the Cu. All the pellets with different temperatures are re-weighed and sintered density are calculated after sintering. Besides that, porosity …

Process Parameter-Microstructure-Mechanical Property Relations Of Sicp-Reinforced Aluminum Composites Produced By Powder-Injection Casting, M Bunma, P Subarporn, R Bobuangern, T Patthannkitdamrong, T Thuanwong, T Patcharawit

Journal of Metals, Materials and Minerals

Aluminum composites are of interest for engineering applications such as electrical and especially automotive applications and their final physical and mechanical properties are usually determined by fabrication techniques. This research aimed to study effects of process parameters, which are i) argon gas flow rates at 5 and 10 l/min, and ii) casting temperatures at 620 and 680C, on integrity of the SiCp-reinforced 356 aluminum composites fabricated by powder-injection casting using a modified flux injection degassing machine. The SiCp additions are 0, 10 and 15 wt.%. Microstructure - mechanical property relations were constructed based on the predetermined process parameters. Aluminum 356 …

Synthesis Of Aligned Carbon Nanotubes By Floating Catalyst Method Using Ferrocene, R Ravindra, B R. Bhat

Journal of Metals, Materials and Minerals

The aligned carbon nanotubes (CNTs) have been synthesised by floating catalyst method using ferrocene as catalyst precursor and acetylene as carbon precursor. The reaction was carried out at 850C in double stage chemical vapor deposition (CVD) apparatus. The grown aligned CNTs were purified by air oxidation and acid treatment method. The aligned CNTs were characterised by using scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The purity of CNTs was determined by Thermal analysis and X-ray diffraction method. The average diameter of aligned CNTs were around 20nm. This process not only produces aligned CNTs but also avoids the preparation …

Development Of A Simulation Tool For Analysis Of Freeway Crashes Due To Cell Phone Usage, Sourabh Sriom

UNLV Theses, Dissertations, Professional Papers, and Capstones

Research shows that drivers are susceptible to numerous distractions while driving which can be held responsible as the reason of a crash. Usage of cell phones, i.e. talking or texting while driving is considered one of the prominent distractions which causes a crash. This dissertation aims to study the number of crashes occurring on the freeways and their relation with the drivers of these cars using cell phones while they are driving. Since crashes occur relatively less frequently, the study of crashes is done using what is called the "rare event" theory. Java based simulations are done to model a …

High Temperature Thermodynamic Properties Of Znte(S), Robert F. Brebrick

Mechanical Engineering Faculty Research and Publications

We have gathered the partial pressure, Knudsen cell, and emf measurements on ZnTe(s) from which the Gibbs energy of formation can be calculated. Published partial pressures of diatomic tellurium have been adjusted to take account of a subsequently published third law analysis of tellurium. The equation used to calculate the total pressure from the rate of mass loss from an extensive set of Knudsen cell measurements has been corrected to give a 5% increase in total pressure and the Gibbs energy of formation has been recalculated. A high temperature heat capacity for ZnTe(s) has been selected from the published data. …

Impedance-Based Detection Of Tissue Using A Multi-Electrode Device, Shane Killian Fleshman

Master's Theses

Melanoma skin cancer is the abnormal growth of the melanocytes – the pigmented cells located in the epidermis. The current gold standard diagnostic technique for determining whether a lesion is cancerous involves subjectively examining suspicious lesions and performing an invasive biopsy to confirm melanoma. This method may neglect some lesions or cause scarring from biopsies that turn out to be benign. Thus, impedance-based detection using a multi-electrode device was investigated as a noninvasive technique to diagnose melanoma skin cancer. The multi-electrode device was designed with 8 equally spaced Ag/AgCl electrodes surrounding one central electrode at a 5 mm radius. The …

Predicting The Acoustic Response Of The Golf Club & Ball Impact Using Finite Elements And The Boundary Element Method, Scott Henry Moreira

Master's Theses

An improved and repeatable method for meshing golf club heads using finite elements in TrueGrid® was developed. Using solid brick elements through the thickness of the club head instead of shell elements better represents the many thickness variations throughout each section of a club head. This method also results in a high quality mesh at the center of the club head sections while still maintaining high quality at the edges. A simulation procedure was also developed to predict the acoustic pressure at a designated point in an acoustic medium of a golf club and ball impact using the BEM and …

Cubesat Constellation Analysis For Data Relaying, Bradley Ryan Smalarz

Master's Theses

Current CubeSat communication technology limits the amount of time, and number of accesses with ground stations. It has been proposed to use a constellation of CubeSats to improve relay performance and increase the number of accesses between a CubeSat and ground stations. By using the spatial and temporal analysis features of STK, coupled with the STK/Matlab interface a robust tool was created to analyze the performance of CubeSat constellations based on a store-and-forward communications model which is not currently supported by the STK Engine. Utilizing the Connect messaging format through a socket connection on the local machine, a Matlab graphical …

Seasonal And Anatomical Variation In Compact Bone Remodeling In The Adult Sheep, Joseph Calcagno

Master's Theses

ABSTRACT

SEASONAL AND ANATOMICAL VARIATION IN COMPACT BONE REMODELING IN THE ADULT SHEEP

Joseph Calcagno

In order to determine whether ovine compact bone is suitable for study of osteoporosis, the remodeling parameters of the untreated animal must be fully characterized. Ovine compact bone is an attractive large animal model due to its similarities in size and bone remodeling to humans. However hormonal, exercise, and dietary changes due to seasonal changes can cause treatment effects to be hidden or superimposed on existing changes in the bone. In order to determine if any seasonal or anatomical variation occurred in the compact bone …

Reducing Moisture Damage In Asphalt Mixes Using Recycled Waste Additives, Anthony John Boyes

Master's Theses

This thesis has determined that using fly ash as a mineral filler in asphalt pavements can help strengthen and reduce asphalt moisture damage. Also, dynamic shear rheometer tests show that these additives have a stiffening effect on asphalt binder. Moisture related damage is considered one of the main causes of asphalt pavement failure. As water infiltrates a layer of asphalt, it slowly strips away asphalt binder, weakening the aggregate/binder bond. This process, combined with the cyclic loading of traffic, can lead to several different types of asphalt failure including rutting, raveling, bleeding, and cracking. For several decades, research has been …

Dimensional Stability Of Geosynthetic Clay Liners In Landfill Applications, Gregory R. Olsen

Master's Theses

An investigation was conducted related to the dimensional stability of geosynthetic clay liners (GCLs) in landfill applications. Multiple occurrences of panel separation of overlap seams in GCLs have been documented; however, explanation for the relative contribution of various mechanisms causing shrinkage has been limited. A systematic test program was conducted to determine the effects of a variety of conditions on GCL dimensional stability.

Effects of initial moisture content, permeant type, and overburden pressure were tested by subjecting various GCL products to wet-dry cycles and measuring the dimensional change with each cycle. Different GCL types were each tested under various combinations …

Analysis Of Contrast Enhancement Methods For Infrared Images, Sprinkle Christian

Master's Theses

Contrast enhancement techniques are used widely to improve the visual quality of images. The difference in luminance reflected from two adjacent surfaces creates contrast between the surfaces in the image. The greater the contrast, the easier it is to recognize and differentiate objects in an image. Thus object contrast is an important factor in the perception of the visual quality of an image and in its usefulness for object recognition and image analysis applications.

The focus of this thesis is on studying how well different contrast enhancement techniques developed for visible spectrum photographic images work on infrared images; to determine …

Modeling And Analysis Of A Four-Switch Buck-Boost Dynamic Capacitor, Oscar Plasencia

Master's Theses

Modern electric power utilities are facing a variety of challenges introduced by the increasing complexity of their operation, structure, and consumer loads. One such challenge has been to supply the ever growing demand for reactive power which is essential for grid support. For this reason dynamic VAR technologies are becoming much more important to modern day power systems. A recent dynamic VAR technology known as the Dynamic Capacitor offers full quadrant capacitive VAR control through the combination of AC/AC buck and boost cells. This paper introduces a new topology deemed the “Four-Switch Buck-Boost Dynamic Capacitor” which promises to combine the …

Global Optimization Of Mga-Dsm Problems Using The Interplanetary Gravity Assist Trajectory Optimizer (Igato), Jason M. Bryan

Master's Theses

Interplanetary multiple gravity assist (MGA) trajectory optimization has long been a field of interest to space scientists and engineers. Gravity assist maneuvers alter a spacecraft's velocity vector and potentially allow spacecraft to achieve changes in velocity which would otherwise be unfeasible given our current technological limitations. Unfortunately, designing MGA trajectories is difficult and in order to find good solutions, deep space maneuvers (DSM) are often required which further increase the complexity of the problem. In addition, despite the active research in the field over the last 50 years, software for MGA trajectory optimization is scarce. A few good commercial, and …

State Estimation For Tracking Of Tagged Sharks With An Auv, Christina Forney

Master's Theses

Presented is a method for estimating the planar position, velocity, and orientation states of a tagged shark. The method is designed for implementation on an Autonomous Underwater Vehicle (AUV) equipped with a stereo-hydrophone and receiver system that detects acoustic signals transmitted by a tag. The particular hydrophone system used here provides a measurement of relative bearing angle to the tag, but does not provide the sign (+ or -) of the bearing angle. A particle filter was used for fusing measurements over time to produce a state estimate of the tag location. The particle filter combined with an active control …

Comet: Constrained Optimization Of Multiple-Dimensions For Efficient Trajectories, Michael Curt Conrad

Master's Theses

The paper describes the background and concepts behind a master’s thesis platform known as COMET (Constrained Optimization of Multiple-dimensions for Efficient Trajectories) created for mission designers to determine and evaluate suitable interplanetary trajectories. This includes an examination of the improvements to the global optimization algorithm, Differential Evolution, through a cascading search space pruning method and decomposition of optimization parameters. Results are compared to those produced by the European Space Agency’s Advanced Concept Team’s Multiple Gravity Assist Program. It was found that while discrepancies in the calculation of ΔV’s for flyby maneuvers exist between the two programs, COMET showed a noticeable …

Enhancement Of Light Absorption Efficiency Of Solar Cell Using Dual, Ashton Ellaboudy

Master's Theses

In this research we study the effect of adding a single diffraction grating on top of a solar cell. We simulated the square diffraction grating, as well as triangular diffraction grating. The single square grating showed more favorable results, achieved 330% power improvement compared to 270% power improvement in the single triangular grating case.

We simulated a triangle/triangle (top-bottom) and triangular/rectangular (top-bottom) grating cases. The Triangular grating achieved higher light absorption compared to rectangular grating. The best top grating was around 200nm grating period. We realized solar cell efficiency improvement about 42.4% for the triangular rectangular (top-bottom) grating.

We studied …

An Inertial Measurement System For Hand And Finger Tracking, Edward Nelson Henderson

Boise State University Theses and Dissertations

The primary Human Computer Interfaces (HCI) today are the keyboard and mouse. These interfaces do not facilitate a fluid flow of thought and intent from the operator to the computer. A computer mouse provides only 2 Degrees of Freedom (2DOF). Touch interfaces also provide 2DOF, but with multiple points, making the touch interface far more expressive. The hand has 6 Degrees of Freedom (6DOF)by itself. Combined with the motion of the fingers, the hand has the potential to represent a vast array of differing gestures. Hand gestures must be captured before they can be used as a HCI. Fortunately, advances …

Effects Of Grain Boundary Character On Dynamic Recrystallization Using A Modified Monte Carlo Method, Michael B. Morse

Boise State University Theses and Dissertations

Dynamic recrystallization (DRX) is the recrystallization that occurs during high temperature deformation of metals and alloys. While DRX has been observed experimentally, the parameters that affect the microstructure are still being explored. For example, the effects of temperature, strain rate, and initial grain size have already been studied, yet the effect of initial special boundary fraction is still unknown. Special boundaries are high-angle, low-energy grain boundaries. It is believed that higher initial fractions of special boundaries will lead to a delay in the onset of recrystallization and a higher peak stress.

Experimentation has shown that triple junctions are preferred nucleation …

Matlab/Simulink Implementation And Analysis Of Three Pulse-Width-Modulation (Pwm) Techniques, Phuong Hue Tran

Boise State University Theses and Dissertations

With advances in solid-state power electronic devices and microprocessors, various pulse-width-modulation (PWM) techniques have been developed for industrial applications. For example, PWM-based three-phase voltage source inverters (VSI) convert DC power to AC power with variable voltage magnitude and variable frequency.

This thesis discusses the advantages and drawbacks of three different PWM techniques: the sinusoidalPWM(SPWM) technique, the third-harmonic-injection PWM(THIPWM) technique, and the space-vector PWM (SVPWM) technique. These three methods are compared by discussing their ease of implementation and by analyzing the output harmonic spectra of various output voltages (poles voltages, line-to-neutral voltages, and line-to-line voltages) and their total harmonic distortion (THD). …

Laser Particulate Counter Calibration To A Micro-Orifice Uniform-Deposit Impactor, Benjamen Fredrich Seely

Boise State University Theses and Dissertations

In semi-arid regions, like southwest Idaho, snowmelt is a significant source of water. Anthropogenic activities continue to increase demand for this vital natural resource. Water resource managers must be able to quantify both the timing and quality of snowmelt. Atmospheric contaminants can deposit on the snow, altering its physical properties. For example, deposition of atmospheric particulate matter (PM) can cause snow to darken, thereby increasing radiative forcing on the snowpack, potentially causing a change in snowmelt timing.

This research is to calibrate a laser particulate counter (LPC) to a federal reference standard. The LPC provides real-time PM concentration data and …

Nondestructive Electrothermal Detection Of Corrosion, Brittany Ambeau, Harris Enniss, Stefan Schnake

Mathematical Sciences Technical Reports (MSTR)

Nondestructive testing and imaging plays an important role in many industries, e.g., the monitoring and maintenance of corrosion in aircraft. The general technique is to input energy in some form into an object, observe the object’s response, and from this input-output information determine the internal structure. New techniques are always being explored, and recently there has been much interest in methods that use multiple forms of energy. In this vein, we examine a new technique for imaging corrosion or material loss in an object by combining electrical and thermal measurements on some accessible portion of the object’s outer boundary. The …

Selective Deposition Of Metallic And Semiconductor Materials Onto Dna Templates For Nanofabrication, Jianfei Liu

Theses and Dissertations

This work examines the selective deposition of metallic and semiconductor materials onto DNA templates for the fabrication of nanodevices. DNA origami provides a simple and robust method for folding DNA into a variety of shapes and patterns and makes it possible to create the complex templates needed for nanodevices, such as nanoelectronic circuits, plasmonics, and nanosensors. Metallization of DNA origami templates is essential for the fabrication of such nanodevices. In addition, selective deposition of semiconductor materials onto the DNA template is of importance for making many nanodevices such as nanocircuits. Metallization of DNA origami presents several challenges beyond those associated …

Structure And Properties Of The Low-Density Phase Ι-Al2o3 From First Principles, Sitaram Aryal, Paul Rulis, Lizhi Ouyang, Wai-Yim Ching

Mathematical Sciences Faculty Research

Of the various phases of transition alumina, iota-alumina (ι-Al2O3) is the least well known. It is considered to be the end member of the mullite series in the limit of zero Si content. The structural details of ι-Al2O3 are not available and its physical properties are totally unknown. Based on an appropriately modified structure of a high alumina content mullite phase close to the 9-1 mullite, we have successfully constructed a structural model for ι-Al2O3. The simulated x-ray diffraction (XRD) pattern of this model agrees well with a measured XRD pattern obtained from samples that claim to belong to ι-Al2O3. …

W.E. Bowers Ans Associates, Inc. Financial Operations Manual For Construction Cost Accounting, Stephen E. Brown

Purdue Polytechnic Masters Theses

W.E. Bowers and Associates, Inc. typically hires experienced project managers eager to

diversify their work experience. W.E. Bowers and Associates, Inc. verbally instructs

project managers to properly utilize the companies forms and the processes for financial

management of projects. The verbal training typically occurs in a piecemeal fashion. It

occurs only when a new project manager asks

“How To” perform specific tasks. The

project managers all come with different backgrounds and with different backgrounds,

come different business management strategies. The creation of this financial operations

manual will aid in the training of project managers and provide the company with a …

In-Situ Ellipsometry Characterization Of Anodically Grown Silicon Dioxide And Lithium Intercalation Into Silicon, Eric A. Montgomery

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

In this thesis, in-situ ellipsometry and electroanalytical investigations of two electrochemical processes are reported: including the formation of anodically grown silicon dioxide and the intercalation of lithium into silicon. Analysis of the ellipsometry data shows that the anodically grown silicon dioxide layer is uniform and has similar properties as thermally grown silicon dioxide. The lithium-ion intercalation data reveals non-uniform thin film formation, which requires further studies and development of appropriate ellipsometric optical models.

Advisers: Eva Schubert and Mathias Schubert