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The Experimental Data Processing (EDP) software is a C++ GUI-based application to streamline the process of creating a model for structural systems based on experimental data. EDP is designed to process raw data, filter the data for noise and outliers, create a fitted model to describe that data, complete a probabilistic analysis to describe the variation between replicates of the experimental process, and analyze reliability of a structural system based on that model. In order to help design the EDP software to perform the full analysis, the probabilistic and regression modeling aspects of this analysis have been explored. The focus has been on creating and analyzing probabilistic models for the data, adding multivariate and nonparametric fits to raw data, and developing computational techniques that allow for these methods to be properly implemented within EDP. For creating a probabilistic model of replicate data, the normal, lognormal, gamma, Weibull, and generalized exponential distributions have been explored. Goodness-of-fit tests, including the chi-squared, Anderson-Darling, and Kolmogorov-Smirnoff tests, have been used in order to analyze the effectiveness of any of these probabilistic models in describing the variation of parameters between replicates of an experimental test. An example using Young's modulus data for a Kevlar-49 Swath stress-strain test was used in order to demonstrate how this analysis is performed within EDP. In order to implement the distributions, numerical solutions for the gamma, beta, and hypergeometric functions were implemented, along with an arbitrary precision library to store numbers that exceed the maximum size of double-precision floating point digits. To create a multivariate fit, the multilinear solution was created as the simplest solution to the multivariate regression problem. This solution was then extended to solve nonlinear problems that can be linearized into multiple separable terms. These problems were solved analytically with the closed-form solution for the multilinear regression, and then by using a QR decomposition to solve numerically while avoiding numerical instabilities associated with matrix inversion. For nonparametric regression, or smoothing, the loess method was developed as a robust technique for filtering noise while maintaining the general structure of the data points. The loess solution was created by addressing concerns associated with simpler smoothing methods, including the running mean, running line, and kernel smoothing techniques, and combining the ability of each of these methods to resolve those issues. The loess smoothing method involves weighting each point in a partition of the data set, and then adding either a line or a polynomial fit within that partition. Both linear and quadratic methods were applied to a carbon fiber compression test, showing that the quadratic model was more accurate but the linear model had a shape that was more effective for analyzing the experimental data. Finally, the EDP program itself was explored to consider its current functionalities for processing data, as described by shear tests on carbon fiber data, and the future functionalities to be developed. The probabilistic and raw data processing capabilities were demonstrated within EDP, and the multivariate and loess analysis was demonstrated using R. As the functionality and relevant considerations for these methods have been developed, the immediate goal is to finish implementing and integrating these additional features into a version of EDP that performs a full streamlined structural analysis on experimental data.
ContributorsMarkov, Elan Richard (Author) / Rajan, Subramaniam (Thesis director) / Khaled, Bilal (Committee member) / Chemical Engineering Program (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Ira A. Fulton School of Engineering (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Along with the number of technologies that have been introduced over a few years ago, gesture-based human-computer interactions are becoming the new phase in encompassing the creativity and abilities for users to communicate and interact with devices. Because of how the nature of defining free-space gestures influence user's preference and the length of usability of gesture-driven devices, defined low-stress and intuitive gestures for users to interact with gesture recognition systems are necessary to consider. To measure stress, a Galvanic Skin Response instrument was used as a primary indicator, which provided evidence of the relationship between stress and intuitive gestures, as well as user preferences towards certain tasks and gestures during performance. Fifteen participants engaged in creating and performing their own gestures for specified tasks that would be required during the use of free-space gesture-driven devices. The tasks include "activation of the display," scroll, page, selection, undo, and "return to main menu." They were also asked to repeat their gestures for around ten seconds each, which would give them time and further insight of how their gestures would be appropriate or not for them and any given task. Surveys were given at different time to the users: one after they had defined their gestures and another after they had repeated their gestures. In the surveys, they ranked their gestures based on comfort, intuition, and the ease of communication. Out of those user-ranked gestures, health-efficient gestures, given that the participants' rankings were based on comfort and intuition, were chosen in regards to the highest ranked gestures.
ContributorsLam, Christine (Author) / Walker, Erin (Thesis director) / Danielescu, Andreea (Committee member) / Barrett, The Honors College (Contributor) / Ira A. Fulton School of Engineering (Contributor) / School of Arts, Media and Engineering (Contributor) / Department of English (Contributor) / Computing and Informatics Program (Contributor)
Created2015-05
Description
This is a lectures series on photovoltaics. As the need for electrical energy rises, mankind has struggled to meet its need in a reliable lasting way. Throughout this struggle, solar energy has come to the foreground as a complete solution. However, it has many drawbacks and needs a lot of development. In addition, the general public is unaware of how solar energy works, how it is made, and how it stands economically. This series of lectures answering those three questions. After two years doing photovoltaic research, and an undergraduate degree in Electrical Engineering, enough expertise has been acquired present on at a late high-school to early college level. Education is key to improving the popularity of using solar energy and the popularity of investing in photovoltaic research. Solar energy is a viable option to satisfy our energy crisis because the materials it requires can quickly be acquired, and there is enough of material to provide a global solution. In addition, the amount of solar energy that hits the surface of the earth in a day is orders of magnitude more than the amount of energy we require. The main goal of this project is to have an effective accessible tool to teach people about solar. Thus, the lectured will be posted on pveducation.com, YouTube, the Barrett repository, and the QUSST website. The content was acquired in four ways. The first way is reading up on the current papers and journals describing the new developments in photovoltaics. The second part is getting in contact with Stuart Bowden and Bill Daukser at Arizona State University's Solar Power Lab as well as the other faculty associated with the Solar Power Lab. There is quite a bit of novel research going on at their lab, as well as a student run pilot line that is actively building solar cells. The third way is reading about solar device physics using device physics textbooks and the PVEducation website made by Stuart Bowden. The forth way is going into ASU's solar power lab.
ContributorsLeBeau, Edward (Author) / Goryll, Michael (Thesis director) / Bowden, Stuart (Committee member) / Dauksher, William (Committee member) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Current solar cells use a silver-printed front grid for electron conduction. Unfortunately, silver is expensive, leading to research into alternative materials. Copper is the most viable but poses grain growth problems and stress problems silver does not. This paper has characterised the effects of proprietary additives, thickness of the copper film layer, current density, and grain growth on stress. Per Stoney's equation, increased thickness leads to decreased thickness. However, if the current density is too high, the plated copper will become porous. Grain growth, quantified by the ratio of the intensity of the (1 1 1) plane and the (2 0 0) plane, increases over time, thus increasing the ratio which further equations to increased stress. Future work would be gathering more data to further investigate the relationship between additives and stress, current densities and stress, and grain growth over time and stress.
ContributorsSimonet, Danny (Co-author) / Chang, Celine (Co-author) / Bowden, Stuart (Thesis director) / Karas, Joseph (Committee member) / Division of Teacher Preparation (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
As global population and demand for electrical power increase, humanity is faced with the growing challenge of harnessing and distributing enough energy to sustain the developing world. Currently, fossil fuels (coal
atural gas) are our main sources of electricity. However, their cost is increasing, they are nonrenewable, and they are very harmful to the environment. Thus, capacity expansion in the renewable energy sector must be realized to offset higher energy demand and reduce dependence on fossil fuels. Solar energy represents a practical solution, as installed global solar capacity has been increasing exponentially over the past 2 decades. However, even with government incentives, solar energy price ($/kWh) continues to be highly dependent on political climate and raw material (silicon and silver) cost. To realistically and cost effectively meet the projected expansions within the solar industry, silver must be replaced with less costly and more abundant metals (such as copper) in the front-grid metallization process of photovoltaic cells. Copper, while offering both higher achievable efficiencies and a raw material cost nearly 100 times cheaper than silver, has inherent disadvantages. Specifically, copper diffuses rapidly into the silicon substrate, requires more complex and error-prone processing steps, and tends to have less adhesive strength, reducing panel robustness. In this study, nickel deposition via sputtering was analyzed, as well as overall potential of nickel as a seed layer for copper plating, which also provides a barrier layer to copper diffusion in silicon. Thermally-formed nickel silicide also reduces contact resistivity, increasing cell efficiency. It was found that at 400 \u00B0C, ideal nickel silicide formation occurred. By computer modeling, contact resistivity was found to have a significant impact on cell efficiency (up to 1.8%). Finally, sputtering proved useful to analyze nickel silicide formation, but costs and time requirements prevent it from being a practical industrial-scale metallization method.
atural gas) are our main sources of electricity. However, their cost is increasing, they are nonrenewable, and they are very harmful to the environment. Thus, capacity expansion in the renewable energy sector must be realized to offset higher energy demand and reduce dependence on fossil fuels. Solar energy represents a practical solution, as installed global solar capacity has been increasing exponentially over the past 2 decades. However, even with government incentives, solar energy price ($/kWh) continues to be highly dependent on political climate and raw material (silicon and silver) cost. To realistically and cost effectively meet the projected expansions within the solar industry, silver must be replaced with less costly and more abundant metals (such as copper) in the front-grid metallization process of photovoltaic cells. Copper, while offering both higher achievable efficiencies and a raw material cost nearly 100 times cheaper than silver, has inherent disadvantages. Specifically, copper diffuses rapidly into the silicon substrate, requires more complex and error-prone processing steps, and tends to have less adhesive strength, reducing panel robustness. In this study, nickel deposition via sputtering was analyzed, as well as overall potential of nickel as a seed layer for copper plating, which also provides a barrier layer to copper diffusion in silicon. Thermally-formed nickel silicide also reduces contact resistivity, increasing cell efficiency. It was found that at 400 \u00B0C, ideal nickel silicide formation occurred. By computer modeling, contact resistivity was found to have a significant impact on cell efficiency (up to 1.8%). Finally, sputtering proved useful to analyze nickel silicide formation, but costs and time requirements prevent it from being a practical industrial-scale metallization method.
ContributorsBliss, Lyle Brewster (Author) / Bowden, Stuart (Thesis director) / Karas, Joseph (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
This is a lectures series on photovoltaics. As the need for electrical energy rises, mankind has struggled to meet its need in a reliable lasting way. Throughout this struggle, solar energy has come to the foreground as a complete solution. However, it has many drawbacks and needs a lot of development. In addition, the general public is unaware of how solar energy works, how it is made, and how it stands economically. This series of lectures answering those three questions.
ContributorsLeBeau, Edward Sanroma (Author) / Goryll, Michael (Thesis director) / Bowden, Stuart (Committee member) / Dauksher, Bill (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
G3Box's 2013 Marketing Plan outlines a strategic plan and short term operational strategies for the company. The document includes a discussion of the company's decision to enter the market for healthcare facilities in developing counties, and a situation assessment of the market conditions. G3Box is targeting small and large NGOs that currently provide healthcare facilities in developing countries. The market size for healthcare aid in developing countries is estimated to be $1.7 billion. The plan also analyses the customer's value chain and buying cycle by using voice of the customer data. The strategic position analysis profiles G3Box's competition and discusses the company's differential advantage versus other options for healthcare facilities in developing countries. Next the document discusses G3Box's market strategy and implementation, along with outlining a value proposition for the company. G3Box has two objectives for 2013: 1) Increase sales revenue to $1.3 million and 2) increase market presence to 25%. In order to reach these objectives, G3Box has developed a primary and secondary strategic focus for each objective. The primary strategies are relationship selling and online marketing. The secondary strategies are developing additional value-added activities and public relations.
ContributorsWalters, John (Author) / Denning, Michael (Thesis director) / Ostrom, Lonnie (Committee member) / Carroll, James (Committee member) / Barrett, The Honors College (Contributor) / Ira A. Fulton School of Engineering (Contributor)
Created2012-12
Description
The majority of the 52 photovoltaic installations at ASU are governed by power purchase agreements (PPA) that set a fixed per kilowatt-hour rate at which ASU buys power from the system owner over the period of 15-20 years. PPAs require accurate predictions of the system output to determine the financial viability of the system installations as well as the purchase price. The research was conducted using PPAs and historical solar power production data from the ASU's Energy Information System (EIS). The results indicate that most PPAs slightly underestimate the annual energy yield. However, the modeled power output from PVsyst indicates that higher energy outputs are possible with better system monitoring.
ContributorsVulic, Natasa (Author) / Bowden, Stuart (Thesis director) / Bryan, Harvey (Committee member) / Sharma, Vivek (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / Ira A. Fulton School of Engineering (Contributor)
Created2012-12
Description
The 21st century engineer will face a diverse set of challenges spread out along a broad spectrum of disciplines. Among others, the fields of energy, healthcare, cyberspace, virtual reality, and neuroscience require monumental efforts by the new generation of engineers to meet the demands of a growing society. However the most important, and likely the most under recognized, challenge lies in developing advanced personalized learning. It is the core foundation from which the rest of the challenges can be accomplished. Without an effective method of teaching engineering students how to realize these grand challenges, the knowledge pool from which to draw new innovations and discoveries will be greatly diminished. This paper introduces the Inventors Workshop (IW), a hands-on, passion-based approach to personalized learning. It is intended to serve as a manual that will inform the next generation of student leaders and inventioneers about the core concepts the Inventors Workshop was built upon, and how to continue improvement into the future. Due to the inherent complexities in the grand challenge of personalized learning, the IW has developed a multifaceted solution that is difficult to explain in a single phrase. To enable comprehension of the IW's full vision, the process undergone to date of establishing and expanding the IW is described. In addition, research has been conducted to determine a variety of paths the Inventors Workshop may utilize in future expansion. Each of these options is explored and related to the core foundations of the IW to assist future leaders and partners in effectively improving personalized learning at ASU and beyond.
ContributorsEngelhoven, V. Logan (Author) / Burleson, Winslow (Thesis director) / Peck, Sidnee (Committee member) / Fortun, A. L. Cecil (Committee member) / Barrett, The Honors College (Contributor) / Ira A. Fulton School of Engineering (Contributor)
Created2012-12
ContributorsShah, Beejal (Author) / Nakamura, Mutsumi (Thesis director) / Balasooriya, Janaka (Committee member) / Wilkerson, Kelly (Committee member) / Ira A. Fulton School of Engineering (Contributor) / Barrett, The Honors College (Contributor)
Created2012-12