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Evaluation of Damages and Economic Losses in Light-Frame Timber Houses
Get PDFThis thesis aims to evaluate the damages and economic losses in light-frame timber houses by designing and constructing a two-story, full-scale, fully equipped, code conforming timber assembly. Specifically, the structure will be analyzed based on how the non-structural components (NSC) like gypsum wallboard, interior doors, windows, and sliding patio doors as well as structural components like light-frame timber shear walls impact the economic losses.
Damage limit states were obtained from the Federal Emergency Management Agency (FEMA) P-58, Performance Assessment of Buildings to extract at what inter-story drift (ISD) ratio each damage limit state was expected to occur at. Fragility and consequent probability functions were developed for the shear walls and NSC to find what the most probabilistic damage limit state was expected at varying hazard levels. From the consequent probability function, global economic losses estimate, and economic losses estimates for each component could be derived.
The thesis found that shear walls perform as intended as they do not see significant damage or economic losses until well after 2% ISD, where the likelihood of an earthquake causing ISD upwards of 3%-5% are extremely slim. The windows and sliding patio door are expected to perform excellently as they are expected to see even less damage and economic losses than the shear walls, which can be attributed to the material makeup and installation technique. The gypsum wallboard and interior doors were the two most fragile elements as they exceeded the most severe damage limit states and required near full replacement at 2% ISD.
This thesis also serves as a prediction for a planned dynamic test on a uniaxial shake table. This research analytically predicts the exceedance of damage limit states and economic losses at various hazard levels for the comparison to dynamic testing to improve the performance of non-structural components in light-frame timber houses
Implementation of Area-Based Aggregation on Multivariate Continuous Uncertain Data
Get PDFUncertain data is incredibly widespread - from sensor data to AI-based learned information, there exists a need to associate information with a certain probability of its veracity. Traditional relational databases lack a built-in functionality to support uncertain data, instead assigning them boilerplate values. Probabilistic databases tackle this problem by assigning non-deterministic data with an associated, often discrete, probability. Variants of probabilistic databases, namely continuous uncertain databases, are used to better model data represented through ranges and distributions. This is especially applicable with sensor-based geographic data as most commercial equipment contains some inherent margin of error.
While uncertain and probabilistic databases contain incredible potential, aggregation on these forms of databases remains inefficient, namely due to the need to consider all present probabilities to compute an exact aggregate. This problem is compounded should we wish to aggregate across some uncertain data. Accordingly, approximation algorithms are often used to compute aggregates within a reasonable bound of accuracy at a much faster rate. Despite extensive prior research on both exact and approximate aggregates, work on computing aggregates of uncertain data across differing uncertain data is lacking; such a situation is especially pertinent with uncertain GIS data due to its numerous data forms and dimensionalities. Specifically, this thesis explores aggregating across regions of uncertain data modeled by two-dimensional distributions, which can be deemed as an aggregation by area.
This thesis presents a multi-step approach to aggregating across multidimensional uncertain data. First, we introduce a framework to model varying forms of uncertain data obtained from a singular source. We then propose multiple algorithms to efficiently conduct aggregation of uncertain data across other uncertain data of differing types, applying them in a GIS-centric case study. More accurate insights, which specifically take uncertainty into account, can be obtained as a result
Enhancement of a Python Integral Boundary Layer Method
Get PDFThis thesis presents a series of additions to a Python based integral boundary layer software library known as PyBL. This library provides the user the means to calculate boundary layer properties using different models for boundary layer behavior. The additions feature the integration of a set of new laminar and turbulent integral boundary layer models originally developed for and currently found in the program XFOIL. These models were modified to fit the ODE solver method at the foundation of PyBL. A new method for PyBL that stitches a laminar and turbulent solution together has been developed to improve the ability to couple laminar and turbulent models, which previously had to be done manually. Furthermore, a velocity treatment scheme was implemented for use with inviscid velocity profiles, in an attempt to address solution convergence issues in PyBL. This work has been verified using a number of resources, ranging from comparisons to analytical solutions, empirical data, and results from XFOIL. The new laminar and turbulent closure solutions integrated into PyBL demonstrated their closer alignment to XFOIL results, which provides confidence in their implementation, as now these models can be utilized for inviscid flow problems beyond airfoils
Design and Development of a Laboratory Star Tracker System
Get PDFThis thesis presents the design, calibration, and validation of a low-cost star tracker system and hardware-in-the-loop testbed intended for small satellite applications. The system is composed entirely of commercial off-the-shelf components and integrates both a custom star tracker and a screen-based star field simulator for controlled, repeatable testing. An analytical modeling approach was used in the early design phase to predict system accuracy based on key optical and geometric parameters, informing the selection and configuration of components and guiding the development of calibration routines.
A simulation environment was developed to validate the star tracker software and assess the impact of noise and distortion on centroiding accuracy. Calibration techniques were implemented to estimate key intrinsic parameters, including focal length, principal point, and optical distortion. The testbed was then used to collect real measurements across a range of known attitudes, enabling detailed error analysis and characterization of measurement noise. The final system supports end-to-end validation of star tracker algorithms in both software and hardware and provides a foundation for future testing and integration with the Cal Poly Spacecraft Attitude Dynamics Simulator. After calibration and misalignment corrections, the system provides an improvement over the previous system and is able to perform attitude determination with a mean angular error of 750 arcseconds. An error characterization campaign and analysis conclude that the leading cause of error is uncorrected distortion caused by the screen and imaging optics of the system
Topiarism: The Kernel Embedding of Distributions Applied to Modern Portfolio Theory
Get PDFThe method of kernel embedding of distributions on a set into a reproducing kernel Hilbert space is a method of studying the space of measures on a set using Hilbert space geometry. Because positively weighted portfolios can be interpreted as nonnegative probability measures on the space of assets, we are able to apply this technique to portfolio theory. In this thesis, we discuss the theory of topiarism , the study of positively weighted probability measures on compact sets under the kernel embedding of distributions. Given a specific payoff function on the set of assets , we optimize a specific function , called the aesthetic objective, by finding maximizing measures. We review different properties, develop an algorithm for locating the maximizer of the function , and discuss applications of this theory to both modern portfolio theory and as a method for rudimentary boundary-finding
UAV & UGV Drone Competition (Raytheon)
Get PDFAutonomous vehicles have been starting to address real-world issues through innovative technology. RTX (Raytheon) needs a way to have two autonomous vehicles, an unmanned air vehicle (UAV), and unmanned ground vehicle (UGV) reliably communicate with each other with the goal of landing and delivering a payload to designated delivery zones. This will foster creativity, innovation, and team-solving skills. Additionally, it will also promote & strengthen university relationships, evaluate top graduates, and promote corporate branding.
This report details the design process of a UAV-UGV delivery system developed for the RTX Autonomous Vehicle Competition (AVC). The system features a custom-built hexacopter UAV and a modified Overlander-4 UGV, both engineered for autonomous payload transport within a 90 ft × 90 ft arena. Final design decisions were driven by performance modeling, weight constraints, and mission requirements. The UAV employs T-Motor MN501-S 360 KV motors with 16×5.5” APC propellers, optimized for a 25 lb takeoff weight and over 20 minutes of flight time. The UGV uses an inclined ramp with closed-loop servo control for reliable, low-power payload deployment. Key priorities included FAA compliance, efficient power usage, and robust system integration. The result is a cost-effective, modular platform showcasing reliable autonomy and interdisciplinary engineering design
Expeditionary Ocean Power Generator
Get PDFThe Expeditionary Ocean Power Generator (ExOPG) project is a point absorber wave energy converter developed by a team of five mechanical engineering seniors at California Polytechnic State University in partnership with NAVFAC EXWC. Designed to support U.S. Marine Corps operations, the device aims to reduce the reliance on diesel generators by generating and storing up to 100 watts of power from ocean waves in a sturdy and self-sufficient device.
The ExOPG device uses a rack and pinion mechanism driven by vertical wave motion to convert mechanical energy into electrical energy via a generator, which is then processed and stored by an electrical subsystem designed by a team of Cal Poly electrical engineers. The final design prioritizes ease of deployment, effective waterproofing using a dynamic O-ring seal, efficient power transmission from the rack to generator across a pinion shaft, and modularity to allow for future teams’ iteration on the project.
The final test deployment confirmed the mechanical system’s functionality and waterproofing, however yielded voltage output fluctuations of around only 3 volts from the incoming waves. The device’s internal weight distribution was not uniform about the center or equal with the center of buoyancy, producing a moment on the device and forcing it to sit at an angle in the water during operation. Thus, the device charged the battery a negligible amount (a few milliwatts) over the hour and a half test. Nonetheless, the system demonstrated viability as a proof of concept and provides a strong foundation for future development. Suggested improvements include redesigning the buoyancy to hold the housing more rigidly, refining the weight distribution for stability, and optimizing power generation for varied wave conditions
Floating Wind Turbine Foundation
Get PDFThe 2024 Collegiate Wind Competition (CWC) has introduced a new element to their Turbine Design Competition: a floating foundation. In previous years, foundations have been fixed-bottom in a box of sand and water. The Cal Poly Wind Power Club, who competes in the CWC every year, requires a floating foundation to be designed, manufactured, and tested to assist in winning the competition. The foundation is a large, hollow, cylindrical barge with a hanging spar (heavy mass). The barge will provide a restoring moment using buoyancy, and the heavy spar provides additional restoring moment. Four cables will be attached at the sides of the barge to the mooring weights to prevent lateral motion. The 12 kg spar will be connected to the 48 cm diameter barge via a threaded aluminum rod and a flange that bolts to the underside of the barge. A central column within the barge will support the load and also allow for mounting studs for the turbine on top of the assembly. At the CWC, the foundation deflected 13 degrees at 13 m/s. It experienced minimal lateral motion, and, as such, the foundation received 50/50 points in the Foundation Success task. Installation was consistently performed in under 60 seconds, and it presented minimal safety hazards at any point during installation and operation
One-Handed Wheelchair
Get PDFA person who uses a wheelchair for mobility needs a way to operate it with only one hand. This may be necessary if they lack functionality in one hand or prefer to use only one hand while operating the wheelchair. Even for users with two available hands, it is difficult to operate As of now, such wheelchairs are not widely available or easily accessible, yet these devices are crucial for improving the quality of life and mobility of many people. The goal of this project is to design a more viable and ergonomic solution for people who operate a wheelchair with one hand
Metabolomics and Physiological Studies on Essential Oils and Prebiotics in Late-Stage Laying Hens
No full textEssential oils (EOs) and prebiotics are increasingly utilized in the poultry industry as beneficial feed supplements that can help maintain gut health and microflora, promote production, and exhibit antimicrobial properties. This study aimed to investigate the effect of feeding EOs and prebiotics to late-stage laying hens and their impact on various metabolomic and physiological parameters. Sixty commercial caged Hy-Line W-80 White Leghorn laying hens were randomly allocated to one of four dietary treatments (15 hens/treatment) and fed ad libitum for twelve weeks. These treatments included 0% control (corn–soybean meal-based basal diet), 0.5% LOW (low EO-based basal diet), 1% HIGH (high EO-based basal diet) diets, and a 1% PRE (prebiotic-based basal diet). Weekly body mass and feed conversion ratio were measured. At the end of the twelfth week, a complete blood profile, metabolomic panels of cecal, serum, and liver samples, and bone strength tests were performed. Liver histopathology was also analyzed. Blood chemistry and bone strength were analyzed using SAS 9.4. All metabolomic data were analyzed using MetaboAnalyst software. Liver histopathology was scored on an ordinal basis, then analyzed using Kruskal-Wallis ANOVA with Dunn’s multiple comparisons test. Blood panels were lowered in prebiotic-treated hens. There was a stepwise decrease in Phosphorus and Calcium levels from control to prebiotic diets. The 0.5% low EO-based basal diet treated birds showed a significant increase (p \u3c 0.05) in Lipemic Index compared to other diets. Cecal metabolites, aspulvinone E and coumestrol, were lowered in control hens and high EO-treated hens, respectively. Prebiotic-fed hens exhibited elevated levels of various significant serum metabolites. Liver metabolites as well as liver histopathology showed no significant differences between treatments (p \u3e 0.05). Likewise, no significant differences were found between treatments for the bone strength. (p \u3e 0.05). Additional research is necessary to determine the functional role of EOs and prebiotics as potential feed additives in the diets of late-stage laying hens