Engineering Commons^™

A Constant Conduction Angle Biased Rf Power Amplifier For Improved Linearization In Class C Operation, Greg Lacaille

Master's Theses

Class C power amplifiers offer higher efficiency than class B power amplifiers, but suffer from poor linearity. A feedback based biasing system to improve the linearity of a class C power amplifier is designed. A class B amplifier with a gain of 20 dB and 20 MHz bandwidth at 900 MHz acts as the launching point for the design. The biasing and output network of the class B power amplifier is modified to produce a class C amplifier at conduction angles of 180°, 162°, 126°, 90°, and 54°. A feedback based biasing system, which uses two matched and scaled down …

Novel Inverse Airfoil Design Utilizing Parametric Equations, Kevin A. Lane

Master's Theses

The engineering problem of airfoil design has been of great theoretical interest for almost a century and has led to hundreds of papers written and dozens of methods developed over the years. This interest stems from the practical implications of airfoil design. Airfoil selection significantly influences the application's aerodynamic performance. Tailoring an airfoil profile to its specific application can have great performance advantages. This includes considerations of the lift and drag characteristics, pitching moment, volume for fuel and structure, maximum lift coefficient, stall characteristics, as well as off-design performance.

A common way to think about airfoil design is optimization, the …

Geo-Engineering Reconnaissance Of The 2010 Maule, Chile Earthquake, Pedro Arduino, Scott Ashford, Dominic Assimaki, Jonathan Bray, Terry Eldridge, David Frost, Youssef Hashash, Tara Hutchinson, Laurie Johnson, Keith Kelson, Robert Kayen, Christian Ledezma, Robb Moss, George Mylonakis, Scott Olson, Kyle Rollins, Nicholas Sitar, Jonathan Stewart, Alfredo Urzua, Ramon Verdugo, Rob Witter, Nick Zoa

Civil and Environmental Engineering

No abstract provided.

Design Of A Low-Cost, Underwater Acoustic Modem For Short-Range Sensor Networks, Bridget Benson, Y. Li., R. Kastner, B. Faunce, K. Domond, D. Kimball, C. Schurgers

Electrical Engineering

A fundamental impediment to the use of dense underwater sensor networks is an inexpensive acoustic modem. Commercial underwater modems that do exist were designed for sparse, long range, applications rather than for small, dense, sensor nets. Thus, we are building an underwater acoustic modem starting with the most critical component from a cost perspective - the transducer. The design substitutes a commercial transducer with a homemade transducer using cheap piezoceramic material and builds the rest of the modem's components around the properties of the transducer to extract as much performance as possible. This paper presents the design considerations, implementation details, …

Shake Table Testing To Quantify Seismic Soil Structure Interaction Of Underground Structures, Robb E.S. Moss, Vic Crosariol, Steven Kuo

Civil and Environmental Engineering

This research uses shake table testing of scale soil-structure models to mimic the coupled seismic response of underground structures and surrounding/supporting soil (termed soil-structural-interaction or SSI). Currently the seismic design of subways and other critical underground infrastructure rely on little to no empirical data for calibrating numerical simulations. This research is working towards filling that empirical data gap. The research is composed of two phases, the first a validation of the free-field response of a flexible wall barrel filled with model soil, the second a test to measure the “racking” deformations induced in a model subway cross-section embedded in the …

Simulation Of Three-Fold Symmetric Photonic Crystal Structures On Top Of Gan Leds, Simeon Trieu, Xiaomin Jin, Chang Xiong, Xingxing Fu, Xiangning Kang, Guoyi Zhang, Bei Zhang

Electrical Engineering

A 3-fold symmetric photonic-crystal grating is simulated using improved FDTD-model. Transmission gratings are optimized. Then, the best cases are simulated in GaN-LED models. The maximum extraction efficiency improvement is 40× greater compared to conventional LEDs.

Comparison Of Model Evaluation Methods To Develop A Comprehensive Watershed Simulation Model, Misgana K. Muleta

Civil and Environmental Engineering

Comprehensive environmental models such as the Soil and Water Assessment Tool (SWAT) are becoming an integral part of decision making processes for effective planning and management of natural resources. Before their use as decision making aid, however, models must be properly evaluated to improve their prediction accuracy and reduce the likelihood of making decisions that could lead to undesirable policy outcomes. Model evaluation refers to practices such as quality analysis of input data, sensitivity analysis, calibration and verification, and uncertainty analysis. Many methodologies have been developed for model evaluations over the years. One of the major limitations of the existing …

Spatial Variability Of Levees As Measured Using The Cpt, Robb E.S. Moss, J. C. Hollenback, J. Ng

Civil and Environmental Engineering

The spatial variability of a soil deposit is something that is commonly discussed but difficult to quantify. The heterogeneity as a function of lateral distance can be critical to the design of long engineered structures such as highways, bridges, levees, and other lifelines. This paper presents a methodology for using CPT measurements to quantifying the spatial variability of cone tip resistance along a levee in the California Bay Delta. The results, presented in the form of a general relative variogram, identify the distance at which the maximum spatial variability is achieved for a given soil strata. This information helps define …

Increased Performance Of Fpga- Based Color Classification System, Junguk Cho, Bridget Benson, Sunsern Cheamanukul, Ryan Kastner

Electrical Engineering

This paper presents a hardware architecture for increased performance of color classification. In our architecture, color classification, based on an AdaBoost algorithm, identifies a pixel as having the color of interest or not. We designed the proposed architecture using Verilog HDL and implemented the design in a Xilinx Virtex-5 FPGA. The architecture for color classification can have 598 times performance improvement over an equivalent software solution and 1.9 times performance improvement over the leading hardware color classifier.

Delamination Of Sandwich Composites, Richard Anthony Davis

Aerospace Engineering

The use of shear keys to help stop or inhibit the face-sheet core delamination of sandwich composite beams under monotonic loading was analyzed in Cal Poly’s structural design lab. The composite beams were treated with the same boundary conditions as the ASTM D5528 double cantilever beam bending in which both faces of the beam remain free; one of the faces would have a debonded side and the other would not. An aluminum tab is attached to the top of the specimens and the load is applied there. Each specimen has piezoelectric sensors that are utilized in the detection of delamination …

Simplified Procedure For Seismic Evaluation Of Piles With Partial-Moment Connection To The Deck In Marine Oil Terminals, Rakesh K. Goel

Civil and Environmental Engineering

This paper presents development of a simplified procedure for seismic evaluation of piles with partial-moment connection typically used in marine oil terminals. The current seismic evaluation procedure of the piles in marine oil terminals includes monitoring material strains specified in the Marine Oil Terminal Engineering and Maintenance Standard (MOTEMS) during the nonlinear static pushover analysis to estimate the displacement capacity of piles. This investigation developed closed-form formulas for estimating the displacement capacity of piles by using a simple pile-deck connection system. The displacement capacity estimated from these formulas ensures that the material stain limits specified in the MOTEMS is not …

Flexural Cracks In Fiber-Reinforced Concrete Beams With Fiber-Reinforced Polymer Reinforcing Bars, Won K. Lee, Daniel C. Jansen, Kenneth B. Berlin, Ian E. Cohen

Civil and Environmental Engineering

Fiber-reinforced polymer (FRP) reinforcing bars have attracted considerable attention for applications where corrosion of steel reinforcement is problematic. Due to the generally low elastic modulus and poor bond characteristics of FRP as compared to steel reinforcing bars, the use of FRP results in larger crack widths under service loads. Fiber-reinforced concrete (FRC) is proposed for use with FRP to reduce crack widths. The work presented herein includes the results from 16 beams tested under four-point bending with either Grade 420 (Grade 60) steel or FRP reinforcing bars, and either plain concrete or FRC. A modified Gergely-Lutz model was applied to …

Teaching Sustainability Analysis In Electrical Engineering Lab Courses, David Braun

Electrical Engineering

Laboratory courses represent an incompletely tapped opportunity to teach sustainability concepts. This work introduces and evaluates a simple strategy used to teach sustainability concepts in electrical engineering laboratory courses. The technique would readily adapt to other disciplines. The paper presents assessment data and a wiki containing student sustainability analyses.

Flying Blanket, Keane Daquioag, Ryan Grable, Eric Reynolds, Kaitlin Spak

Mechanical Engineering

This report contains the design plan for PolyNet Design’s Senior Design Project. The PolyNet Design team comprises four mechanical engineering seniors who created a prototype for Raytheon Missile Systems. The overall goal of this project was to create a system that will launch a blanket from a packaged and folded state to an unfurled state and then securely wrap the blanket around a target. The team began with five initial concepts, and chose the Four-Rod model as their first construction concept. Construction of the Four Rod model evolved through several design iterations. The team tested the final prototype extensively, using …

Cal Poly Sit Ski: Final Report, Marc Bergreen, David Bydalek, Ross Gompertz

Mechanical Engineering

The purpose of this project was to design, build, and test a Sit Ski for the US Adaptive Ski Team. The design is for Mr. Marlon Shepard, a new competitor on the Ski Team, who is in need of a new racing sit ski. Some of the top design priorities include reduced weight, increased rider comfort, and increased durability over existing designs. With these design considerations in mind, our team from Cal Poly designed, built and tested a cross country sit ski in June 2010 at the mechanical engineering senior project expo. The project was sponsored by a National Science …

Effects Of Reamer-Femoral Component Offset On Cement Mantle Penetration In Hip Resurfacing Arthroplasty, Mark Lloyd Paulick

Master's Theses

Hip resurfacing arthroplasty has changed the treatment of end stage arthritis without severe deformity for young, active adults. Presently, there are varying clinical approaches to implant design selection and cementation techniques. The purpose of this project is to determine what amount of reamer-femoral component offset allows for the best cement penetration into the femoral head.

Rapid prototyped femoral component models were produced with reamer femoral component offsets of 0.0 mm, 0.5 mm, and 1.0 mm. After implantation onto models of reamed femoral heads made from high-density open-cell reticulated carbon foam, cement penetration was assessed from cross-sections of the foam-implant unit. …

Hidra: Hierarchical Inter-Domain Routing Architecture, Bryan Clevenger

Master's Theses

As the Internet continues to expand, the global default-free zone (DFZ) forwarding table has begun to grow faster than hardware can economically keep pace with. Various policies are in place to mitigate this growth rate, but current projections indicate policy alone is inadequate. As such, a number of technical solutions have been proposed. This work builds on many of these proposed solutions, and furthers the debate surrounding the resolution to this problem. It discusses several design decisions necessary to any proposed solution, and based on these tradeoffs it proposes a Hierarchical Inter-Domain Routing Architecture - HIDRA, a comprehensive architecture with …

Design, Construction And Evaluation Of Side Mount Truck Tool Boxes And Fuel Transfer Tank, Trey Avila

BioResource and Agricultural Engineering

This senior project discusses the design, construction, evaluation and cost analysis of side mounted truck tool boxes and a fuel transfer tank. The need for the boxes arose when specific tools and extra fuel had to be carried at all times. The objective was to build a set of tool boxes and a fuel transfer tank to fit a Ford short bed and still have a four foot wide area in between the boxes. Results show objective being met, but cost analysis shows that it’s not feasible for low scale production.

Screen Printing Scheduling Methodology, Brandon Wolfe, Kyle Naylor

Graphic Communication

As the shift towards offshore business within the screen printing industry increases, American businesses must find a way to remain competitive. Due to manufacturing costs and regulation it is impossible for Americans to compete with the low per unit cost of foreign suppliers. By decreasing the time to market, American businesses will be able to remain competitive and recover lost business. In order to achieve this, a flexible scheduling model must be developed in order to increase throughput of a production process. This model serves to account for variables and variances that occur within the screen printing process, allowing for …

Catheter Laser Drill, Brady Haug

Industrial Technology and Packaging

The project that I have undertaken is to improve upon an existing machine and process at Applied Medical, a medical device company. The machine is used to drill four holes into the body of a catheter. The holes are located on a linear axis, rotated 90 degrees apart from each other. Currently, the machine utilizes a traditional drill bit to create the four holes. This creates burrs along the holes, which increases the manufacturing time because a worker must remove them. The project calls for the use of a laser to replace the drill bit. The machine designed through this …

A Sustainable Business Proposition For Selling Irrigation Pumps In Ndola, Zambia, Robert Hosbach

Biomedical Engineering

Robert Hosbach is proposing a sustainable business plan to bring a small‐scale irrigation pump to rural Ndola, Zambia. With hundreds of thousands of citizens living in poverty and semi‐annual starvation, Ndola is in need of a means to grow crops effectively in the rainy season. Their current agricultural practices rely solely on the inconsistent rainfall during this time. My pump will be constructed from locally‐available aluminum cans, epoxy, glue, and fasteners (refer to Appendix B for technical drawings of the pump). The business will employ only a small number of Zambians, but will bring a means of food and income …

Finite Element Modeling Of Icd Lead Silicone Soft-Tips, Jose J. Lepe

Master's Theses

Although highly underutilized by the medical device industry, Finite Element Analysis (FEA) in the development of new technologies is gaining popularity as regulatory bodies such as the Food and Drug Administration (FDA) begin to require additional proof of safety through scientific methods. Non-linear FEA allows engineers to realistically simulate the mechanical behavior of implants as seen in the in-vitro, or in some cases, the in-vivo configurations. The work presented in this report investigates how computational methods can be used to simulate the interaction of a St. Jude Medical silicone soft-tip as it passes through a Peel-Away Sheath (i.e. introducer). In …

Computer Simulation To Manage Lean Manufacturing Systems, Ahmed Deif

Industrial Technology and Packaging

There is a difference between a lean manufacturing system and a manufacturing system that just applies lean techniques. This paper addresses the previous statement through using computer simulation to explore the impact of applying just in time lean policy on a traditional inventory based production system. A system dynamics model is introduced to capture the different components of the production system. The inventory dynamics of the modeled system is examined against different production scenarios under stochastic demand. Results showed that in systems that are not fully transferred to lean, adopting lean principles are not always beneficial. The paper suggests some …

Role Of Faculty In Promoting Lifelong Learning: Characterizing Classroom Environments, Susan M. Lord, John Chen, Katharyn E. K. Nottis, Candice Stefanou, Michael J. Prince, Jonathon Stolk

Mechanical Engineering

Calls for educational reform emphasize the need for student-centered learning approaches that foster lifelong learning. To be a lifelong learner includes characteristics consistent with those of self-directed learners, such as being curious, motivated, reflective, analytical, persistent, flexible, and independent. Educational research has shown that the building of these aptitudes involves a complex interplay among nearly every aspect of human development. Instructor support of students’ self-directed learning (SDL) development relies on understanding and balancing these factors in the classroom. Engineering educators play a critical role in influencing outcomes related to SDL through their design of courses that support students’ transitions from …

Multiphase Interleaving Buck Converter With Input-Output Bypass Capacitor, Taufik, Randyco Prasetyo, Arief Hernadi, Dodi Garinto

Electrical Engineering

As the number of transistors in microprocessors increases per Moore's Law their power requirement increases accordingly. This poses design challenges for their power supply module especially when microprocessors operate at sub voltage range. This paper presents a new multiphase topology that addresses these challenges. Laboratory tests on a hardware prototype of the topology shows improved performance compared to a commercially available power supply module.

Experimental Development Of Compressor And Turbine Performance Maps For Turbomachinery, Michael W. Green

Aerospace Engineering

Turbomachinery performance maps are used to reveal the on and off design performance of compressors and turbines. These maps plot the component’s pressure ratio versus the corrected flow rate for multiple engine rotor speeds. In this experiment, a Boeing T50-BO-8A converted turbojet engine was operated at a wide variety of rotor speeds with orifice plates of different sizes to vary the flow rate. The corrected flow rate through the turbojet ranged from 1.32 to 2.55 lb/s. The pressure ratios for the compressor and turbine ranged from 2.0 to 4.3 and from 1.7 to 4.3, respectively. The resulting performance maps showed …

The Concept Of Proactive Traffic Management For Enhancing Freeway Safety And Operation, Mohamed Abdel-Aty, Anurag Pande, Liang Hsia

Civil and Environmental Engineering

No abstract provided.

Classes That Click: Fast, Rich Feedback To Enhance Student Learning And Satisfaction, John C. Chen, Dexter C. Whittinghill, Jennifer A. Kadlowec

Mechanical Engineering

No abstract provided.

Pretty Lights, Nicholas (Nick) Delmas, Matthew (Matt) Maniaci

Computer Engineering

Digital media players often include a visualization component that allows a user to watch a visualization synchronized to their music or videos. This project uses the visualization plugin API of an existing media playback program (WinAmp) but it displays its visuals using physical LED lights. Instead of outputting visuals to the computer screen, data is sent over USB to a micro controller that runs the LED lights. This project aims to give users a more visceral visual experience than traditional visualizations on the computer screen.

Locked Plate Fixation Of Osteoporotic Humeral Shaft Fractures: Are Two Locking Screws Per Segment Enough?, David J. Hak, Peter Althausen, S J. Hazelwood

Biomedical Engineering

Objective: The purpose of this study was to compare the biomechanical behavior of using two versus three locking screws per bone segment in a cadaveric humerus fracture gap model.

Methods: Six matched pairs of elderly osteoporotic fresh–frozen human cadaveric humerii were used. An eight-hole locking compression plate was placed posteriorly on the humeral shaft and secured with either four or six bicortical locking screws. A 5-mm middiaphyseal gap osteotomy was created to simulate a comminuted fracture without bony contact. Specimens were tested in offset axial compression, four-point anteroposterior bending, four-point medial– lateral bending, and torsion. After the initial testing in …