Engineering Commons^™

Nanoindentation Of Annealed And As-Sputtered Thin Films Of Nickel Titanium Shape Memory Alloys, Matthew Tyson Lewis

Master's Theses

The bottom-up processing techniques used for making Microelectromechanical systems (MEMS) devices can produce material properties different from bulk processing. The material properties must be evaluated with the process parameters used and for changes in the process parameters. The mechanical properties are needed to design MEMS devices. A material of interest for MEMS devices is nickel titanium (NiTi) shape memory alloy (SMA) because of the high work output (~107 J/m3). This thesis will focus on the fabrication of thin film NiTi by DC magnetron sputtering deposition and testing mechanical properties of the fabricated films by nanoindentation. Thin film NiTi SMA was …

Study Of Top And Bottom Photonic Gratings On Gan Led With Error Grating Models, Simeon S. Trieu, Xiaomin Jin

Electrical Engineering

The gallium nitride (GaN) light-emitting-diode (LED) top-bottom (or transmission-reflection) grating simulation results with error grating model are presented. The microstructure GaN bottom hole and top pillar gratings are calculated and compared with the non-grating (flat) case. Grating shapes simulated are either conical or cylindrical. A direct comparison of 181 different combined transmission-reflection grating cases using the finite difference time domain method is presented. The simulation results show that simple or direct combinations of the optimized top grating with the optimized bottom grating only produce a 42% light extraction improvement compared to the non-grating case, which is much lower than that …

A Realistic Technology And Engineering Assessment Of Algae Biofuel Production, T. J. Lundquist, I. C. Woertz, N. W. T. Quinn, J. R. Benemann

Civil and Environmental Engineering

This report assesses the economics of microalgae biofuels production through an analysis of five production scenarios. These scenarios, or cases, are based on technologies that currently exist or are expected to become available in the near-term, including raceway ponds for microalgae cultivation, bioflocculation for algae harvesting, and hexane for extraction of algae oil. Process flow diagrams, facility site layouts, and estimates for the capital and operations costs of each case were developed de novo. This report also reviews current and developing microalgae biofuel technologies for both oil and biogas production, provides an initial assessment of the US and California …

A Classification Tree Based Modeling Approach For Segment Related Crashes On Multilane Highways, Anurag Pande, Mohamed Abdel-Aty, Abhishek Das

Civil and Environmental Engineering

Introduction: This study presents a classification tree based alternative to crash frequency analysis for analyzing crashes on mid-block segments of multilane arterials.

Method: The traditional approach of modeling counts of crashes that occur over a period of time works well for intersection crashes where each intersection itself provides a well-defined unit over which to aggregate the crash data. However, in the case of mid-block segments the crash frequency based approach requires segmentation of the arterial corridor into segments of arbitrary lengths. In this study we have used random samples of time, day of week, and location (i.e., milepost) …

Motorcycle Data Acquisition System, Jonathan Luke Harmse

Biomedical Engineering

No abstract provided.

Traffic Safety Investigations For Local Agencies, Jacob D. Hudson

Master's Theses

National and statewide (California) collision numbers are currently on the

decline; however, the U.S. is declining at a much slower rate than most other

developed countries, and in some aspects is actually regressing in terms of traffic

safety. Although state highway safety is improving, local roadway safety may

actually be regressing. Approximately three-quarters of all U.S. public roadways,

and approximately 80% of all injury accidents fall under the jurisdiction of cities.

However, cities may not be allocating the proper level of resources, or operating

under the proper administrative methodologies to adequately address these

safety issues.

This research finds that on …

Effect Of Freeze-Thaw Cycling On The Compression Strength Of Folding Cartons Made From Different Materials, Koushik Saha, Bruce Harte, Gary Burgess, Sujeet Adudodla

Industrial Technology and Packaging

The quality of frozen food is known to deteriorate in storage due to water migration, in-pack desiccation and frost formation. These same factors can affect folding cartons. The rate of frozen food and folding carton deterioration is further dependent on temperature fluctuations during storage, transportation, loading and unloading. This study was conducted to compare the compression strength of folding cartons made from CNK (Coated Natural Kraft), SBS (Solid Bleached Sulfate), CRP (Coated recycled paperboard) and PCSBS (Poly coated Solid Bleach Sulfate) after subjecting them to multiple freeze-thaw cycles. Compression tests were performed on empty cartons and cartons filled with frozen …

Life Cycle Inventory Comparison Of Paper And Plastic Based Packaging Systems For Strawberry Distribution, Jay A. Singh, Aric Krasowski

Industrial Technology and Packaging

The goal of this study was to conduct a life Cycle Inventory (Lei) analysis based comparison of eleven primary container and pillow wrap combinations for the distribution of fresh strawberries Three of the primary containers studied were paper based (molded pulp, paperboard and corrugated fiberboard) and three other containers investigated were clamshells or punnets made of polyethylene terephthalate (PET) and recycled PET (rPET) Pillow wraps made of rPET and polylactlde (PLA) were also Included for all punnet/tray style containers The scope of the study ranged from the extraction of raw materials, their processing and formation for all packaging components, product …

R&D Of A Dual Mode Acoustic Modem Testbed For Shallow Water Channels, Feng Tong, Shengyong Zhou, Bridget Benson, Ryan Kastner

Electrical Engineering

Recent years witnessed an increasing requirement of marine missions like oceanographic investigation, environmental monitoring, underwater structure inspection and sea bottom resource exploitation, which urged the R&D of high performance underwater acoustic (UWA) modems. However, as underwater acoustic channels pose multiple difficulties such as multipath, time-space selectivity, frequency dependent noise, and Doppler shifts on transmission, currently there is not a single modulation strategy that can provide high data rate, energy efficiency and channel robustness simultaneously. Enlightened by the similar dual mode (DM) systems developed in wireless channels, this paper presents the R&D of a DM UWA modem testbed system, which enables …

Base Shear Estimated From Floor Accelerations And Column Shears, Rakesh K. Goel

Civil and Environmental Engineering

This paper compares base shear computed from floor accelerations (inertial base shear) and column shears (structural base shear) for several single-degree-of-freedom (SDF) systems and two mid-rise, multi-story buildings due to a suite of 30 earthquake ground motions. The presented results show that the inertial base shear is close to structural base shear in short-period (<1 >sec) SDF systems but may significantly exceed the structural base shear for individual ground motions in longer period (> 1 sec) SDF systems. Furthermore, the inertial base shear exceeds the structural base shear in the median by 10% to 20% and may exceed the structural …

Design And Wind Tunnel Testing Of Cal Poly's Amelia 10 Foot Span Hybrid Wing-Body Low Noise Cestol Aircraft, Kristina K. Jameson, David D. Marshall, Robert Ehrmann, Eric Paciano, Rory Golden, Dave Mason

Aerospace Engineering

California Polytechnic Corporation, Georgia Tech Research Institute (GTRI), and DHC Engineering collaborated on a NASA NRA to develop and validate predictive capabilities for the design and performance of Cruise Efficient, Short TakeOff and Landing (CESTOL) subsonic aircraft. In addition, a large scale wind tunnel effort to validate predictive capabilities for aerodynamic performance and noise during takeoff and landing has been undertaken.

The model, Advanced Model for Extreme Lift and Improved Aeroacoustics (AMELIA), was designed as a 100 passenger, N+2 generation, regional, CESTOL airliner with hybrid blended wingbody with circulation control. The model design was focused on fuelsavings and noise goals …

Mission Performance As Point Performance, Robert A. Mcdonald

Aerospace Engineering

The cruise or loiter performance of an aircraft is intimately tied to its wing loading (W/S) and its thrust to weight ratio (T/W). Paradoxically, mission performance is often not considered when these fundamental aircraft parameters are determined in conceptual design. In this research, the traditional constraint diagram is extended to include contours of range parameter. This point performance metric represents the mission performance capability of the aircraft without sizing the aircraft to a particular mission. This gives the designer an immediate and intuitive understanding of the tradeoff between the point and mission performance of the aircraft. This improved constraint diagram …

Subcritical Contraction For Improved Open-Channel Flow Measurement Accuracy With An Upward-Looking Advm, Daniel Howes, Charles M. Burt, Brett F. Sanders

BioResource and Agricultural Engineering

Acoustic Doppler velocity meters (ADVMs) provide an alternative to more traditional flow measurement devices and procedures such as flumes, weirs, and stage rating for irrigation and drainage canals. However, the requirements for correct calibration are extensive and complex. A three-dimensional computational fluid dynamics (CFD) model was used to design a subcritical rapidly varied flow contraction that provides a consistent linear relationship between the upward-looking ADVM sample velocity and the cross-sectional average velocity in order to improve ADVM accuracy without the need for in situ calibration. CFD simulations validated the subcritical contraction in a rectangular and trapezoidal cross section by showing …

Commercial Sand Media Filter Tank Criteria For Energy Efficiency - Agricultural Drip Irrigation, Charles M. Burt

BioResource and Agricultural Engineering

Sand media filters are commonly used in agricultural drip irrigation systems. They have the advantages of simplicity and large capacities, and are favored by many farmers and designers over other filtration hardware. The primary justification for the research described in this report was to determine if it is possible and reasonable to use lower-than-accepted backflush pressures and thereby reduce the total pressure requirement for drip systems.

Design Of A Low-Cost Underwater Acoustic Modem, Bridget Benson, Ying Li, Brian Faunce, Kenneth Domond, Don Kimball, Curt Schurgers, Ryan Kastner

Electrical Engineering

There has been an increasing interest in creating short-range, low data rate, underwater wireless sensor networks for scientific marine exploration and monitoring. However, the lack of an inexpensive, underwater acoustic modem is preventing the proliferation of these sensor networks. 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 letter describes the high level design, …

Parameter Estimation Of Fundamental Technical Aircraft Information Applied To Aircraft Performance, Michael Vallone

Master's Theses

Inverse problems can be applied to aircraft in many areas. One of the disciplines within the aerospace industry with the most openly published data is in the area of aircraft performance. Many aircraft manufacturers publish performance claims, flight manuals and Standard Aircraft Characteristics (SAC) charts without any mention of the more fundamental technical information of the drag and engine data. With accurate tools, generalized aircraft models and a few curve-fitting techniques, it is possible to evaluate vehicle performance and estimate the drag, thrust and fuel consumption (TSFC) with some accuracy. This thesis is intended to research the use of aircraft …

Performance-Based Analysis Of Steel Buildings: Special Concentric Braced Frame, Scott Michael Adams

Master's Theses

The performance-based analysis methods and evaluation criteria in ASCE 41-06 were used to evaluate a special concentric braced frame building based on the design standards in ASCE 7-05. A rectangular, six-story office building was evaluated using linear static, linear dynamic, nonlinear static, and nonlinear dynamic procedures. The results showed that the linear procedures underestimated damage compared to the nonlinear procedures, with the building performing to Life Safety for the linear procedures, and the nonlinear procedures indicating component damage beyond the intended Life Safety limit for the 2/3 maximum considered earthquake (MCE) hazard. This trend continued to the maximum considered earthquake …

An Investigation Of Damage Arrestment Devices Application With Fastener/Hole Interaction, Richard Vincent S. Balatbat

Master's Theses

This thesis presents a parametric study on the effects of how damage arrestment devices application interacts with a fastener in a composite sandwich panel. The primary objective of the damage arrestment device was to prevent the failure of the composite face sheet, such as crack propagation, around the hole/fastener joint. The damage arrestment devices are made of composite strips that are inserted under the face sheet to increase the overall structural strength of the panel and to prevent the propagation of failure along the hole. This was supposed to be a quicker and stronger alternative to potted inserts for composite …

Sae Baja: Final Drive Gearbox, Michael Mccausland, Michael Watkins, Ian Masterson, Andrew Sommer

Mechanical Engineering

This paper presents the results of a manual transmission project for SAE Baja. A full engineering process is documented, including problem definition, scheduling, conceptualization, decision theory, synthesis, analysis, manufacturing, and testing. A comparison is made between existing and potential mechanical power train solutions. The final design is analyzed in dynamic simulations, AGMA stress, predicted FFT spectrums, and shifting rod buckling. A number of complicated parts are manufactured through investment casting and direct CNC machining. Issues in the final assembly have prevented the project from being fully realized, recommendations are made for future SAE Baja teams.

Differential Regulation Of Immature Articular Cartilage Compressive Moduli And Poisson’S Ratios By In Vitro Stimulation With Igf-1 And Tgf-Β1, Gregory M. Williams, Kristin J. Dills, Christian R. Flores, Michael E. Stender, Kevin M. Stewart, Lauren M. Nelson, Albert C. Chen, Koichi Masuda, Scott J. Hazelwood, Stephen M. Klisch, Robert L. Sah

Mechanical Engineering

Mechanisms of articular cartilage growth and maturation have been elucidated by studying composition-function dynamics during in vivo development and in vitro culture with stimuli such as insulin-like growth factor-1 (IGF-1) and transforming growth factor-beta 1 (TGF-β1). This study tested the hypothesis that IGF-1 and TGF-β1 regulate immature cartilage compressive moduli and Poisson’s ratios in a manner consistent with known effects on tensile properties. Bovine calf articular cartilage from superficial-articular (S) and middle-growth (M) regions were analyzed fresh or following culture in medium with IGF-1 or TGF-β1. Mechanical properties in confined (CC) and unconfined (UCC) compression, cartilage matrix composition, and explant …

Differential Regulation Of Immature Articular Cartilage Compressive Moduli And Poisson's Ratios By In Vitro Stimulation With Igf-1 And Tgf-Β1, Gregory M. Williams, Kristin J. Dills, Christian R. Flores, Michael E. Stender, Kevin M. Stewart, Lauren M. Nelson, Albert C. Chen, Koichi Masuda, Scott J. Hazelwood, Stephen M. Klisch, Robert L. Sah

Biomedical Engineering

Mechanisms of articular cartilage growth and maturation have been elucidated by studying composition-function dynamics during in vivo development and in vitro culture with stimuli such as insulin-like growth factor-1 (IGF-1) and transforming growth factor-beta 1 (TGF-β1). This study tested the hypothesis that IGF-1 and TGF-β1 regulate immature cartilage compressive moduli and Poisson’s ratios in a manner consistent with known effects on tensile properties. Bovine calf articular cartilage from superficial-articular (S) and middle-growth (M) regions were analyzed fresh or following culture in medium with IGF-1 or TGF-β1. Mechanical properties in confined (CC) and unconfined (UCC) compression, cartilage matrix composition, and explant …

Development Of A Small And Inexpensive Terrain Avoidance System For An Unmanned Aerial Vehicle Via Potential Function Guidance Algorithm, Shane Alan Wallace

Master's Theses

Despite the first unmanned aerial vehicle (UAV) mission being flown on Aug 22 1849 to bomb Venice UAVs have only recently began to modernize into sophisticated tools beyond simple aerial vehicles. With an increasing number of potential applications, such as cargo delivery, communications, search and rescue, law enforcement, and homeland security, the need for appropriate UAV technology advancement also arose. Here, the development of a low-cost collision avoidance system is described. Hardware was tested and selected based on predetermined constraints and goals. Additionally, a variety of potential functions were explored and assessed at their effectiveness in preventing a collision of …

State Space Model Of A Light Weight Flexible Telescope, Chi-Yeh Hsu

Master's Theses

The accuracy of optical telescope in the past was dominated by the construction of the telescope body and the precision of optical surface. This thesis fits into a larger project with a goal of controlling a flexible telescope in order to help a cheaper telescope achieve higher accuracy. In order to understand the internal motion of telescope, the goal of this thesis is to build a state space model of a two-degree-of-freedom telescope using a known star location as feedback. The model presented in this thesis may be used for the telescope simulation and the control design in the future. …

Multi-Frequency Processing For Lumen Enhancement With Wideband Intravascular Ultrasound, Rory A. Carrillo

Master's Theses

The application of high frequency ultrasound is the key to higher resolution intravascular ultrasound (IVUS) images. The need to further improve the IVUS spatial resolution may drive the transducer center frequency even higher than the current 40 MHz range. However, increasing the center frequency may be challenging as it leads to stronger scattering echoes from blood. The high level of blood scattering echoes may obscure the arterial lumen and make image interpretation difficult. Blood backscatter levels increase with transmission center frequency at a much greater rate compared to arterial tissue. These different frequency dependencies provide a potential method to distinguish …

Evaluating Effectiveness Of Best Management Practices To Control Accelerated Sedimentation Of The Morro Bay Estuary, Misgana K. Muleta

Civil and Environmental Engineering

The Morro Bay estuary, located on the central Coast of California approximately half way between Los Angeles and San Francisco, is one of the most important wetlands on the west Coast as it supports wide variety of habitats including numerous sensitive and endangered plant and animal species. Various studies have identified accelerated erosion and subsequent sedimentation as a major threat for sustainability of the bay. Watershed disturbances caused by agricultural activities are believed to be one of the major causes of the accelerated erosion and sedimentation. More than 200 conservation practices have been installed in the watershed since the mid-1990 …

Corrosion Dynamics Of Cobalt-Chromium Alloy F-75 Powder, Tedman Tong

Master's Theses

The increasing usage of metal-on-metal joint replacements consisting of a cobalt-chromium-molybdenum alloy requires increasing concern regarding the inevitable generation of metallic wear debris. Patients with these joint replacements exhibit elevated concentrations of cobalt and chromium ions within their serum, blood and urine. The presence of these metal ions suggests the potential for bodily damage and indicates corrosive processes are acting upon wear debris.

To understand the behavior of these corrosive processes, powders of cobalt-chromium-molybdenum alloy F-75 were studied. Four powder sizes (44, 74, 105, and 420 µm diameter) were subjected to Hank’s Balanced Salt Solution (HBSS) for a 42 day …

The Effects Of Applied Strain And Heat Treatment On The Properties Of Niti Wire During Shape Setting, Frank Zapoticla

Master's Theses

NiTi components are commonly subjected to thermo-mechanical heat treatments during production and fabrication. This study investigates the effects of applied strain of 0-10% and heat treatments of 300-600ºC for times of 2-30 minutes during shape-setting of Ti–50.8 at% Ni wire with a nominal diameter of 0.495 mm and an initial transition temperature, Af, of 12ºC. Strain was applied prior to heat treatments by coiling NiTi wire, essentially producing coiled springs, around different diameter steel mandrels to obtain different strain levels. The samples of NiTi wire under applied strain were heat treated in a salt bath, followed by a rapid quench. …

Spatial And Temporal Temperature Distributions In Municipal Solid Waste Landfills, James L. Hanson, Nazli Yesiller, Nicolas K. Oettle

Civil and Environmental Engineering

Long-term spatial and temporal variations in temperatures have been investigated in covers, wastes, and liners at four municipal solid waste landfills located in different climatic regions: Alaska, British Columbia, Michigan, and New Mexico. Temperatures were measured in wastes with a broad range of ages from newly placed to old (up to 40 years). The characteristic shape of waste temperature versus depth relationships consisted of a convex temperature profile with maximum temperatures observed at central locations within the middle third fraction of the depth of the waste mass. Lower temperatures were observed above and below this central zone, with seasonal fluctuations …

Compaction Characteristics Of Municipal Solid Waste, James L. Hanson, Nazli Yesiller, Shawna A. Von Stockhausen, Wilson W. Wong

Civil and Environmental Engineering

Compaction characteristics of municipal solid waste (MSW) were determined in the laboratory and in the field as a function of moisture content, compactive effort, and seasonal effects. Laboratory tests were conducted on manufactured wastes using modified and 4X modified efforts. Field tests were conducted at a MSW landfill in Michigan on incoming wastes without modifications to size, shape, or composition, using typical operational compaction equipment and procedures. Field tests generally included higher efforts and resulted in higher unit weights at higher water contents than the laboratory tests. Moisture addition to wastes in the field was more effective in winter than …

Development Of Measurement Methods For Application To A Wind Tunnel Test Of An Advanced Transport Model, Robert S. Ehrmann

Master's Theses

California Polytechnic State University, San Luis Obispo is currently working towards developing a Computational Fluid Dynamics (CFD) database for future code validation efforts. Cal Poly will complete a wind tunnel test on the Advanced Model for Extreme Lift and Improved Aeroacoustics (AMELIA) in the National Full-Scale Aerodynamics Complex (NFAC) 40 foot by 80 foot wind tunnel at NASA Ames Research Center in the summer of 2011. The development of two measurement techniques is discussed in this work, both with the objective of making measurements on AMELIA for CFD validation.

First, the work on the application of the Fringe-Imaging Skin Friction …