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Articles 4651 - 4680 of 9983
Full-Text Articles in Engineering
Scalable Cognitive Radio Network Testbed In Real Time, Kevin Z. Yu
Scalable Cognitive Radio Network Testbed In Real Time, Kevin Z. Yu
Master's Theses
Modern society places an increasingly high demand on data transmission. Much of that data transmission takes place through communication over the frequency spectrum. The channels on the spectrum are limited resources. Researchers realize that at certain times of day some channels are overloaded, while others are not being fully utilized. A spectrum management system may be beneficial to remedy this efficiency issue. One of the proposed systems, Cognitive Radio Network (CRN), has progressed over the years thanks to studies on a wide range of subjects, including geolocation, data throughput rate, and channel handoff selection algorithm, which provide fundamental support for …
The Application Of Post-Hoc Correction Methods For Soft Tissue Artifact And Marker Misplacement In Youth Gait Knee Kinematics, Kaila L. Lawson
The Application Of Post-Hoc Correction Methods For Soft Tissue Artifact And Marker Misplacement In Youth Gait Knee Kinematics, Kaila L. Lawson
Master's Theses
Biomechanics research investigating the knee kinematics of youth participants is very limited. The most accurate method of measuring knee kinematics utilizes invasive procedures such as bone pins. However, various experimental techniques have improved the accuracy of gait kinematic analyses using minimally invasive methods. In this study, gait trials were conducted with two participants between the ages of 11 and 13 to obtain the knee flexion-extension (FE), adduction-abduction (AA) and internal-external (IE) rotation angles of the right knee. The objectives of this study were to (1) conduct pilot experiments with youth participants to test whether any adjustments were necessary in the …
Soarnet, Deep Learning Thermal Detection For Free Flight, Jake T. Tallman
Soarnet, Deep Learning Thermal Detection For Free Flight, Jake T. Tallman
Master's Theses
Thermals are regions of rising hot air formed on the ground through the warming of the surface by the sun. Thermals are commonly used by birds and glider pilots to extend flight duration, increase cross-country distance, and conserve energy. This kind of powerless flight using natural sources of lift is called soaring. Once a thermal is encountered, the pilot flies in circles to keep within the thermal, so gaining altitude before flying off to the next thermal and towards the destination. A single thermal can net a pilot thousands of feet of elevation gain, however estimating thermal locations is not …
Reducing Vale's Memory Management Overhead Through Static Analysis, Theodore C. Watkins
Reducing Vale's Memory Management Overhead Through Static Analysis, Theodore C. Watkins
Master's Theses
Vale is a multi-purpose programming language that focuses on guaranteeing memory safety with minimal effect on performance. To accomplish this, Vale utilizes a memory management system called Hybrid Generational Memory (HGM). HGM uses generational references to track the state of objects in memory, and static analysis to reduce memory management overhead at runtime. This thesis describes the program that performs static analysis on Vale source code during compilation, and analyzes its effect on the performance of Vale programs.
Design And Characterization Of Standard Cell Library Using Finfets, Phanindra Datta Sadhu
Design And Characterization Of Standard Cell Library Using Finfets, Phanindra Datta Sadhu
Master's Theses
The processors and digital circuits designed today contain billions of transistors on a small piece of silicon. As devices are becoming smaller, slimmer, faster, and more efficient, the transistors also have to keep up with the demands and needs of the daily user. Unfortunately, the CMOS technology has reached its limit and cannot be used to scale down due to the transistor's breakdown caused by short channel effects. An alternative solution to this is the FinFET transistor technology, where the gate of the transistor is a three dimensional fin that surrounds the transistor and prevents the breakdown caused by scaling …
Microfluidic Electrical Impedance Spectroscopy System Automation And Characterization, Keaton Frahmann
Microfluidic Electrical Impedance Spectroscopy System Automation And Characterization, Keaton Frahmann
Master's Theses
In this work, a novel microfluidic cell culture platform capable of automated electrical impedance measurements and immunofluorescence and brightfield microscopy was developed for further in-vitro cellular research intended to optimize cell culture conditions. The microfluidic system design, fabrication, automation, and design verification testing are described. Electrical and optical measurements of the 16 parallel cell culture chambers were automated via a custom LabView interface. A proposed design change will enable gas diffusion, removing the need for an environmental enclosure and allow long-term cell culture experiments. This "lab on a chip" system miniaturizes and automates experiments improving testing throughput and accuracy while …
Development Of A Portable Low-Moisture Food Pasteurization Device Using Rf Heating, Eric Jason Ohata
Development Of A Portable Low-Moisture Food Pasteurization Device Using Rf Heating, Eric Jason Ohata
Master's Theses
Bacterial presence in low-moisture foods such as flour, cereals, baby formula, and spices, have become a concern due to sanitizing challenges. The food industry currently focuses on wet food sanitation as opposed to low-moisture foods because of bacteria’s inability to reproduce in low water activity media. Traditionally, food processing RF heating pasteurizes in mass quantities while an equivalent consumer device does not exist the market today. A consumer product would help eliminate food waste by providing an easy way to sanitize food and extend shelf life. The Portable Food Pasteurization (PFP) project is an interdisciplinary project involving the Electrical Engineering, …
Prediction Of In-Plane Stiffnesses And Thermomechanical Stresses In Cylindrical Composite Cross-Sections, Bryson M. Chan
Prediction Of In-Plane Stiffnesses And Thermomechanical Stresses In Cylindrical Composite Cross-Sections, Bryson M. Chan
Master's Theses
Accurate mechanical analysis of composite structures is necessary for the prediction of laminate behavior. Cylindrical composite tubes are a mainstay in many structural applications. The fundamental design of circular composite cross-sections necessitates the development of a comprehensive composite lamination theory. A new analytical method is developed to characterize the behavior of thin-walled composite cylindrical tubes using a modified plate theory. A generated numerical solver can predict properties such as axial stiffness, bending stiffness, layer stresses, and layer strains in composite tubes subjected to combined mechanical loading and thermal effects. The model accounts for the curvature by transforming and translating the …
An Artificial Neural Network For Bankruptcy Prediction, Walter D. Magdefrau
An Artificial Neural Network For Bankruptcy Prediction, Walter D. Magdefrau
Master's Theses
Assessing the financial health of organizations remains a topic of great interest to economists, financial institutions, and invested stakeholders. For more than a century, research into financial distress has focused primarily on traditional applications of statistical analysis; however, modern advances in computational efficiency have created a significant opportunity for more sophisticated approaches. This thesis investigates the application of artificial intelligence on company bankruptcy prediction. The proposed neural network model is evaluated using the Polish Companies Bankruptcy dataset and yields a 5-year prediction accuracy of 96.5% and an AUC (area under receiver operating characteristic curve) measure of 92.4%.
A Power System-Based Iot Network For Remote Sensing Applications, Dominic Gaiero
A Power System-Based Iot Network For Remote Sensing Applications, Dominic Gaiero
Master's Theses
Cities around the world are facing increasingly significant challenges, including rapid urbanization, resource management, and environmental threats. In California for example, wildfires present an ever-growing threat that gravely harms people, destroys communities, and causes billions of dollars in damages. The task of addressing these environmental threats and many other challenges is greatly aided with widespread data collection and real-time inference. However, as IoT networks scale and require more energy for near-data analytics, the IoT endpoints require more power and complexity, limiting their deployment. Additionally, deploying endpoints in remote locations creates further challenges with higher reliability and communication constraints. In this …
Analytical, Numerical, And Computational Methods To Analyze The Time To Empty Open, Closed, And Variable-Topped Inverted Bottles, Callen Schwefler
Analytical, Numerical, And Computational Methods To Analyze The Time To Empty Open, Closed, And Variable-Topped Inverted Bottles, Callen Schwefler
Master's Theses
Recent unexpected experimental observations of the emptying of inverted bottles with perforations has generated interest in modeling and simulation of this phenomenon. It was observed that as a perforation, i.e., a small hole at the "top" of the inverted bottle, is added and enlarged, the overall emptying time first increases to a maximum value and then decreases until it reaches a lower limit. The change in emptying time is associated with a transition from jetting, where only water exits the neck, to glugging, a competition between air and water flows at the neck of the bottle.
This paper develops analytical …
Perishable Food Waste Reduction Through Technological Implementation At The Retail Level Of The Food Supply Chain, Cassandra Harriman
Perishable Food Waste Reduction Through Technological Implementation At The Retail Level Of The Food Supply Chain, Cassandra Harriman
Master's Theses
Food waste has become a disaster of global proportion that the world can no longer turn a blind eye to. This paper aims to reduce food waste at the retail level of the food supply chain by recommending and quantifying the effects of current technology that can be implemented in traditional supermarkets. This research recommends that retailers implement electronic shelf labels in stores and employ dynamic pricing of perishable products, leading to reduction of food waste. No prior research had considered the primary goal of reducing food waste while preserving retailer profit through technological implementation. This paper quantifies the effects …
Dependencyvis: Helping Developers Visualize Software Dependency Information, Nathan Lui
Dependencyvis: Helping Developers Visualize Software Dependency Information, Nathan Lui
Master's Theses
The use of dependencies have been increasing in popularity over the past decade, especially as package managers such as JavaScript's npm has made getting these packages a simple command to run. However, while incidents such as the left-pad incident has increased awareness of how vulnerable relying on these packages are, there is still some work to be done when it comes to getting developers to take the extra research step to determine if a package is up to standards. Finding metrics of different packages and comparing them is always a difficult and time consuming task, especially since potential vulnerabilities are …
Label-Free Multiphoton Microscopy For The Detection And Monitoring Of Calcific Aortic Valve Disease, Ishita Tandon, Kyle P. Quinn, Kartik Balachandran
Label-Free Multiphoton Microscopy For The Detection And Monitoring Of Calcific Aortic Valve Disease, Ishita Tandon, Kyle P. Quinn, Kartik Balachandran
Biomedical Engineering Faculty Publications and Presentations
Calcific aortic valve disease (CAVD) is the most common valvular heart disease. CAVD results in a considerable socio-economic burden, especially considering the aging population in Europe and North America. The only treatment standard is surgical valve replacement as early diagnostic, mitigation, and drug strategies remain underdeveloped. Novel diagnostic techniques and biomarkers for early detection and monitoring of CAVD progression are thus a pressing need. Additionally, non-destructive tools are required for longitudinal in vitro and in vivo assessment of CAVD initiation and progression that can be translated into clinical practice in the future. Multiphoton microscopy (MPM) facilitates label-free and non-destructive imaging …
Power Output Modeling And Optimization For A Single Axis Tracking Solar Farm On Skewed Topography Causing Extensive Shading, Logan J. Smith
Power Output Modeling And Optimization For A Single Axis Tracking Solar Farm On Skewed Topography Causing Extensive Shading, Logan J. Smith
Master's Theses
Many utility-scale solar farms use horizontal single axis tracking to follow the sun throughout the day and produce more energy. Solar farms on skewed topography produce complex shading patterns that require precise modeling techniques to determine the energy output. To accomplish this, MATLAB was used in conjunction with NREL weather predictions to predict shading shapes and energy outputs. The MATLAB models effectively predicted the sun’s position in the sky, panel tilt angle throughout the day, irradiance, cell temperature, and shading size. The Cal Poly Gold Tree Solar Farm was used to validate these models for various lengths of time. First, …
Failure Analysis Of The Ulnar Collateral Ligament For Youth Baseball Pitchers, Carlos Soto
Failure Analysis Of The Ulnar Collateral Ligament For Youth Baseball Pitchers, Carlos Soto
Master's Theses
The objectives of this study were to (1) use kinetics from motion analysis and inverse dynamics to calculate the stress experienced by the ulnar collateral ligament (UCL) during a typical pitch cycle, (2) compare calculated maximum UCL pitching stresses to failure properties, and (3) investigate correlations between UCL stress with anthropometric and pitching biomechanical parameters. Prior motion analysis experiments of eighteen 10- to 11- year-old baseball pitchers throwing 10 fastballs were analyzed. Maximum internal elbow varus torques were calculated using inverse dynamics methods during a typical pitch cycle. Calculations used axial loading stress equations and maximum internal elbow varus torques …
Cal Poly Preschool Learning Lab Music Garden Design, Karl Heuchert
Cal Poly Preschool Learning Lab Music Garden Design, Karl Heuchert
Construction Management
Colleges, universities and other educational institutions are always looking to improve their learning environments in order to provide students with the best resources, so that they can get the best education. This idea of improving learning environments not only applies to higher education but should be applied to primary education, especially for younger children. Young children should have a learning environment that they can actively engage with that can help them become more creative. This project aims to create a new environment for preschoolers that can allow them to interact with to test their cognitive skills and to give the …
San Luis Obispo Botanical Garden Amphitheater Bench Project – Concrete Formwork Construction, Kyler N. Cruz
San Luis Obispo Botanical Garden Amphitheater Bench Project – Concrete Formwork Construction, Kyler N. Cruz
Construction Management
This paper summarizes the efforts towards constructing formwork for 10 concrete benches. The formwork construction is a part of the San Luis Obispo Botanical Garden amphitheater seating senior project. The project included the design, construction, and installation of precast concrete benches to create seating for 40 people. The project was completed by Kyler Cruz, Brandon Keefer, Sydnee Greer, Makenna Gitchell, Devin Barthmaier, and Anthony Masarweh. The concrete formwork consisted of plywood, 2x4 lumber for bracing, rebar cages, and foam inserts. The key considerations for this scope of work included: reinforcing rebar, the number of forms built, formwork failure, and the …
Requirements Metrics - A Working List, William L. Honig
Requirements Metrics - A Working List, William L. Honig
Computer Science: Faculty Publications and Other Works
A working set of metrics for review of requirements materials including documents.
Establishing Suitable Metrics To Encourage Broader Use Of Atomic Requirements, William L. Honig
Establishing Suitable Metrics To Encourage Broader Use Of Atomic Requirements, William L. Honig
Computer Science: Faculty Publications and Other Works
Despite the apparent benefits of singular, individual, or atomic requirements, their use remains limited, and teaching their creation is difficult. The acceptance of a set of requirements metrics specifically designed to evaluate atomic requirements may lead to their better utilization and improved requirements engineering. Twelve metrics designed to measure atomic requirements are presented here: six used on individual requirements statements and six applied to a requirements document or set of requirement statements. Example metrics for individual requirements are Requirement Completeness and Requirement Atomicity; examples to measure multiple requirements include Requirements Traceablity and Requirements Purity. These metrics are designed to work …
Journeyman International: Haiti Hac Innovation Center In Croix Des Bouquets, Brent K. Underwood
Journeyman International: Haiti Hac Innovation Center In Croix Des Bouquets, Brent K. Underwood
Construction Management
The purpose of this project was to create and provide the necessary pre-construction documents for a multi-purpose building in Croix des Bouquets, Haiti. This project aims to give occupants a new space to work freely in as it will be equipped with the essential needs. The rooms to be included within this building are offices, meeting rooms, general spaces, a workshop and computer lab – all of which will give the occupants the ability to work in an innovative environment. The project is overseen by three organizations. These groups are Journeyman International (JI), the Haitian American Caucus (HAC), and Third …
Learn By Giving: Non-Profit Information For Future Senior Projects, Ryan H. Proctor
Learn By Giving: Non-Profit Information For Future Senior Projects, Ryan H. Proctor
Construction Management
This report details the processes, deliverables, and partnerships between various non-profit construction organizations to provide students with accessible information about non-profit construction companies for future senior projects. The information and deliverables of this senior project also to be found in the portal for the construction management preliminary senior project class (CM 460). One of the main goals of this senior project is to encourage students to sharpen construction skills while helping communities in need. This project consists of interviewing local, national, and international non-profit companies to compile information so students understand the different opportunities they have. The first deliverable that …
The Impact Of Myoblast Transplantation On Collateral Capillary Arteriogenesis And Macrophage Phenotype, Christine Hue Do
The Impact Of Myoblast Transplantation On Collateral Capillary Arteriogenesis And Macrophage Phenotype, Christine Hue Do
Biomedical Engineering
Gangrene, pain, loss of limb function, amputation, and death are only few of the grievous consequences associated with peripheral arterial disease (PAD), a vascular disease caused by an obstruction that narrows the blood vessels. Since some patients have collateral vessels that can re-route blood to its downstream destination, much focus has been spotlighted upon discovering the mechanism of this process, termed arteriogenesis, as well as cell therapies to increase arterial diameter of collateral vessels. Since some patients do not have native pre-existing collateral vessels, another method to re-route blood is through arterialized collateral capillaries (ACC), which is the conversion of …
Calibrated Tensioner For Total Knee Arthroplasty Gap Balancer, Lauren Henigman, Jaypreet Dhanota, Corey Catuara
Calibrated Tensioner For Total Knee Arthroplasty Gap Balancer, Lauren Henigman, Jaypreet Dhanota, Corey Catuara
Biomedical Engineering
The purpose of this project was to design a device that interfaces with the previously created gap balancer to simultaneously measure the gap between the femur and tibia and measure the tension in the ligaments of the knee. First, we met with Dr. Delagrammaticas to outline the key customer requirements: we wanted the device to be precise, sterilizable, reliable, and compatible with the gap balancer. Based on the customer requirements, we outlined the specifications that would drive our design and testing, which included precision, ease of use, size, and material properties. The design process began by using a morphology to …
Stair Wagon To Heaven, Maria Cristina Solis Andrade, Nick Ryan Dion, Alexander Pham
Stair Wagon To Heaven, Maria Cristina Solis Andrade, Nick Ryan Dion, Alexander Pham
Biomedical Engineering
Our design process began with developing a list of questions for our sponsor based on the problem statement we were provided. We took these questions to interview our sponsor. From this interview, we derived a series of customer requirements, which were then used to develop our more specific engineering specifications (Table 8.1). We used these engineering specifications to develop a design morphology. Each of our group mates used the concepts from our design morphology to develop their own full concept sketches. We used Pugh charts to compare the different aspects of each design. The designs were compared based off their …
Integrated Mixing Machine For Sulfur Concrete Production, Maisa El Gamal, Khaled El-Sawy, Abdel-Mohsen O. Mohamed
Integrated Mixing Machine For Sulfur Concrete Production, Maisa El Gamal, Khaled El-Sawy, Abdel-Mohsen O. Mohamed
All Works
The production of sulfur concrete (SC) from its ingredient materials requires controlled heating and mixing conditions at a temperature level of 130°-150 °C. Although this process considered to be common and applicable at the industrial level, it is difficult at the laboratory/research level. This paper presents the design and manufacturing details of a relatively inexpensive laboratory machine for heating and mixing sulfur concrete. The different components of the machine are described in detail to help researchers to produce high-quality sulfur concrete. In this work, the quality of the machine is verified through experimental testing of the physical and mechanical properties …
Real-Time Machine Learning For Quickest Detection, Yongxin Liu
Real-Time Machine Learning For Quickest Detection, Yongxin Liu
Doctoral Dissertations and Master's Theses
Safety-critical Cyber-Physical Systems (CPS) require real-time machine learning for control and decision making. One promising solution is to use deep learning to discover useful patterns for event detection from heterogeneous data. However, deep learning algorithms encounter challenges in CPS with assurability requirements: 1) Decision explainability, 2) Real-time and quickest event detection, and 3) Time-eficient incremental learning.
To address these obstacles, I developed a real-time Machine Learning Framework for Quickest Detection (MLQD). To be specific, I first propose the zero-bias neural network, which removes decision bias and preferabilities from regular neural networks and provides an interpretable decision process. Second, I discover …
Comparison Of Airline Co-Branded Credit Card Programs Via Frequent Flyer Money Saver Analysis For Full-Service U.S. Carriers, Bora Suavi Unsal
Comparison Of Airline Co-Branded Credit Card Programs Via Frequent Flyer Money Saver Analysis For Full-Service U.S. Carriers, Bora Suavi Unsal
Doctoral Dissertations and Master's Theses
Although airline alliances work fairly effectively for paid flight segments, passengers who want to redeem frequent flyer miles often encounter difficulties. Sometimes airlines demand an extensive amount of air miles to book requests for award seats to not only their partner airline customers but also their own customers. Furthermore, while the airline co-branded credit card award mile earnings and redemption rates fluctuate significantly between different airlines, passengers are not well informed about which airline co-branded credit card requires the minimum amount of credit card expenditure to fly with an award ticket to their desired travel destination.
A more useful and …
Adaptive-Optimal Control Of Spacecraft Near Asteroids, Madhur Tiwari
Adaptive-Optimal Control Of Spacecraft Near Asteroids, Madhur Tiwari
Doctoral Dissertations and Master's Theses
Spacecraft dynamics and control in the vicinity of an asteroid is a challenging and exciting problem. Currently, trajectory tracking near asteroid requires extensive knowledge about the asteroid and constant human intervention to successfully plan and execute proximity operation. This work aims to reduce human dependency of these missions from a guidance and controls perspective. In this work, adaptive control and model predictive control are implemented to generating and tracking obstacle avoidance trajectories in asteroid’s vicinity.
Specifically, direct adaptive control derived from simple adaptive control is designed with e modification to track user-generated trajectories in the presence of unknown system and …
Novel And Fast Peridynamic Models For Material Degradation And Failure, Siavash Jafarzadeh
Novel And Fast Peridynamic Models For Material Degradation And Failure, Siavash Jafarzadeh
Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research
Fracture is one of the main mechanisms of structural failure. Corroded surfaces with chemically-induced damage are, notably, potential sites for crack initiation and propagation in metals, which can lead to catastrophic failure of structures. Despite some progress in simulating fracture and damage using classical models, realistic prediction of complex damage progression and failure has been out of reach for many decades. Peridynamics (PD), a nonlocal theory introduced in 2000, opened up new avenues in modeling material degradation and failure. Existing numerical methods used to discretize PD equations, however, are quite expensive as the PD nonlocal interactions make them unaffordable for …