Matching Items (45)
Description
This report analyzes the potential for accumulation of boron in direct potable reuse. Direct potable reuse treats water through desalination processes such as reverse osmosis or nanofiltration which can achieve rejection rates of salts sometimes above 90%. However, boron achieves much lower rejection rates near 40%. Because of this low rejection rate, there is potential for boron to accumulate in the system to levels that are not recommended for potable human consumption of water. To analyze this issue a code was created that runs a steady state system that tracks the internal concentration, permeate concentration, wastewater concentration and reject concentration at various rejection rates, as well as all the flows. A series of flow and mass balances were performed through five different control volumes that denoted different stages in the water use. First was mixing of clean water with permeate; second, consumptive uses; third, addition of contaminant; fourth, wastewater treatment; fifth, advanced water treatments. The system cycled through each of these a number of times until steady state was reached. Utilities or cities considering employing direct potable reuse could utilize this model by estimating their consumption levels and input of contamination, and then seeing what percent rejection or inflow of makeup water they would need to obtain to keep boron levels at a low enough concentration to be fit for consumption. This code also provides options for analyzing spikes and recovery in the system due to spills, and evaporative uses such as cooling towers and their impact on the system.
ContributorsDoidge, Sydney (Author) / Fox, Peter (Thesis director) / Perreault, Francois (Committee member) / Civil, Environmental and Sustainable Engineering Program (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
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
There are many factors that influence the college decision process, but rural students face a unique set of challenges because of the environment in which they make the decision. This is a qualitative study that combines a review of previous literature on the subject with a survey of twelve students from the graduating class of 2011 in a rural area of Arizona. Results from the interviews found that the rural students consider the perception of importance of a college degree, parental influence, and self-discovery as important factors in the decision making process. In addition, not all non-college-going students felt that college was necessary for a better quality of living, but did express desire for more development opportunities while in high school. The findings resulted in the following recommendations for local educators to help students better navigate the college decision process: teach parents how to have more meaningful conversations, provide step-by-step assistance to students about the college application process, and provide more opportunities for self/educational/career development to students.
ContributorsCrow, Ellyse Diann (Author) / Wang, Lili (Thesis director) / Hollin, Michelle (Committee member) / Barrett, The Honors College (Contributor) / Division of Educational Leadership and Innovation (Contributor) / School of Community Resources and Development (Contributor) / W. P. Carey School of Business (Contributor) / Department of Management (Contributor)
Created2015-05
Description
Various reports produced by the National Research Council suggest that K-12 curricula expand Science, Technology, Engineering, and Mathematics to better help students develop their ability to reason and employ scientific habits rather than simply building scientific knowledge. Every spring, the Arizona Department of Education (ADE) in conjunction with Arizona State University holds a professional development workshop titled "Engineering Practices in the Secondary Science Classroom: Engineering Training for Grade 6-12 Math and Science School Teams". This workshop provides math and science teachers with the opportunity to either sustain existing engineering proficiency or be exposed to engineering design practices for the first time. To build teachers' proficiency with employing engineering design practices, they follow a two-day curriculum designed for application in both science and math classrooms as a conjoined effort. As of spring 2015, very little feedback has been received concerning the effectiveness of the ASU-ADE workshops. New feedback methods have been developed for future deployment as past and more informal immediate feedback from teachers and students was used to create preliminary changes in the workshop curriculum. In addition, basic laboratory testing has been performed to further link together engineering problem solving with experiments and computer modelling. In improving feedback and expanding available material, the curriculum was analyzed and improved to more effectively train teachers in engineering practices and implement these practices in their classrooms.
ContributorsSchmidt, Nathan William (Author) / Rajan, Subramaniam (Thesis director) / Neithalath, Narayanan (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2015-05
Description
The 8.1 magnitude earthquake that struck Mexico City in 1985 left 10,000 people dead, and over 400 buildings collapsed. The extent of the damage left behind by this powerful quake has been extensively studied to make improvements to engineering and architectural practices in earthquake-prone areas of the world. Thirty-two years later, on the exact anniversary of the devastating earthquake, Mexico City was once again jolted by a 7.1 magnitude earthquake. Although still significant, the 2017 earthquake collapsed only about a tenth of the buildings collapsed by the 1985 Earthquake, and in turn resulted in a lower death toll. Even though these earthquakes struck in the same seismic region, their effects were vastly different. This thesis completes a comparison between the two earthquakes focusing on the structural impacts including background on Mexico City's unique geology, basic concepts necessary to understand the response of structures to earthquake excitation, and structural failure modes observed in both earthquakes. The thesis will also discuss the earthquake's fundamental differences that led to the discrepancy in structural damage and ultimately in lower death tolls. Of those discussed, is the types of buildings that were targeted and collapsed. In 1985, buildings with 6 or more floors had the highest damage category. Resonance frequencies of these buildings were similar to the resonance frequencies of the subsoil, leading to amplified oscillations, and ultimately in failure. The 2017 earthquake did not have as much distance from the epicenter for the high frequency seismic waves to be absorbed. In contrast, the shorter, faster waves that reached the capital affected smaller buildings, and spared most tall buildings.
ContributorsGonzalez, Diana Laura (Author) / Hjelmstad, Keith (Thesis director) / Ward, Kristen (Committee member) / Civil, Environmental and Sustainable Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The loading provisions were compared between the ASCE 7-10 standard and ASCE 7-16 standard. Two different structural models were considered: an office building with a flat roof located in Tempe and a community center with a gable roof located in Flagstaff. The following load types were considered: dead, live, wind, and snow loads. The only major changes between the standards were found in the wind load calculations. The winds loads were reduced by approximately 22% for the office building in Tempe and 37% for the community center in Flagstaff. A structural design was completed for the frame of the Flagstaff community building. There was a 19% reduction in cost from the design using ASCE 7-10 provisions compared to the design utilizing ASCE 7-16 provisions, leading to a saving of $7,599.17. The reduction in loading, and subsequently more cost-effective design, is attributed to the reduction in basic wind speed for the region and consideration of the ground elevation factor. The introduction of the new ASCE 7-16 standard was met with criticism, especially over the increase in specific coefficients in the wind load and seismic load chapters. Proponents of ASCE 7-16 boast that the new chapter on tsunami loads, new maps for various environmental loads, and a new electronic hazard are some of the merits of the newest standard. Others still question whether the complexity of the provisions is necessary and call for further improvements for the wind and seismic provisions. While tension exists in the desire for a simple standard, ASCE 7-16 prioritizes in having its provisions provide economical and reliable results. More consideration could be devoted to developing a more convenient standard for users. Regardless, engineering professionals should be able to adapt alongside newly developed practices and newly discovered data.
ContributorsCajegas, Cyam Joshua Dato (Author) / Rajan, Subramaniam (Thesis director) / Neithalath, Narayanan (Committee member) / Civil, Environmental and Sustainable Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Consumers purchase point-of-use (POU) devices to further improve the quality of water provided by the tap. As awareness increases of harmful contaminants, an emerging market of advanced POU with claims of removing beyond what a typical activated carbon filter is capable of, such as heavy metals. This research compares four commercially available pitcher filters; two that claim to remove arsenic and hexavalent chromium and two without such claims. Arsenate (As (V)) and hexavalent chromium (Cr (VI)) co-occur in natural geologic formations and are known to have harmful effects on humans when ingested. Pitcher filters Epic Water Filter and Aquagear had claims of removing both As (V) and Cr (VI) up to 99% with a capacity of nearly 200 gallons. In contrast, pitcher filters Brita and Pur had no claims for removal of As(V) and Cr(VI) with a 40-gallon lifespan. A series of experiments were conducted to first determine the efficiency of each filter, then to add the ability or improve removal of As(V) and Cr(VI) in one filter for future design implementations. Experiment 1 was conducted by treating 100 gallons of spiked tap water (50 ppb for As (V) and 100 ppb for Cr (VI)) with each filter. All four pitcher filters showed low performance, resulting in Pur with the lowest removal percentage of 2% and Aquagear with the highest percentage 16% for As (V). For Cr (VI) Pur performed the worst with a removal of 5% and Brita had the best performance of 15%. The functionality of Brita was improved by embedding a selective ion exchange media, which when nanotized successfully removed Cr (VI) in previous studies. The optimal mass of resin to add to the pitcher was experimentally determined as 18.9 grams through Experiment 2. Finally, Experiment 3 compared an alternative placement of the resin material using the same 18.9 grams. The performance in Experiment 3 was significantly worse than Experiment 2. The final recommendation for future design implementation was to add 18.9 grams of SIR-700 resin below the filter media for optimum performance. Overall, the results demonstrate the limited removal of As(V) and Cr(VI) by the four commercial pitcher filters and show that by adding selective ion exchange media, the POUs can be nano-enabled to effectively remove As(V) and Cr(VI) from water.
ContributorsDietrich, Lisa Keri (Author) / Westerhoff, Paul (Thesis director) / Perreault, Francois (Committee member) / Civil, Environmental and Sustainable Engineering Program (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Asphalt pavements deteriorate over time and are subjected to various distresses like rutting, fatigue cracking, stripping, raveling, etc. In this study, an experiment to indirectly assess aggregate stripping was completed in order to evaluate the effect of type of binder, and aging on the binder-aggregate bond under dry conditioning. The asphalts used in the study are commonly used in the state of Arizona, which included both non-polymer modified and polymer modified asphalts. The phenomenon of stripping was simulated using the Bitumen Bond Strength Test (BBS) and evaluated for Arizona binders. The BBS test is a simple test that measures the "pull-off" tensile strength of the bond between asphalt and the aggregate. Polymer modified binders were found to have lower pull-off strength in comparison to the non-modified or neat binder which were found to possess greater pull-off strength, but lower elasticity, causing the failure to become brittle and spontaneous. However, when aged binder was used, the bond strength expectedly reduced for non-polymer modified asphalts but surprisingly increased for polymer modified asphalts. Both un-aged neat and polymer modified binders were observed to have a cohesive failure whereas only the aged polymer modified binders failed in cohesion. The aged non-polymer modified binders were seen to have an adhesive failure.
ContributorsPonce, Esai Jonathon (Author) / Kaloush, Kamil (Thesis director) / Gundla, Akshay (Committee member) / Civil, Environmental and Sustainable Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
In the Spring 2013 and Fall 2013 semesters, a survey was taken of students enrolled in the principal undergraduate civil engineering structures course, CEE 321: Structural Analysis and Design, to assess both the prevalence of technology in the lives of the students and the potential ways this information could be use to improve the educational experience. The results of this survey indicated that there was a considerable demand for additional online resources outside of the formal classroom. The students of CEE 321 requested online lecture videos in particular, and so a project was launched at the start of the Spring 2014 semester to deliver a large body of academic instructional videos. In total, a collection of 30 instructional videos which covered all key topics covered over a semester of CEE 321 was published. The driving interest behind this creative project is to increase the level of understanding, comfort, and performance in students enrolled in the class. Although the quantity of initial student feedback is relatively small, the reactions are distinctly positive and reflect an improvement in understanding amongst the responding students. Over the course of upcoming semesters, qualitative and quantitative assessments of the impact of the videos are expected to provide a better indication of their quality and effectiveness in supporting student comprehension and performance in CEE 321. Above all, the success of these videos is directly tied to their ability to function as living, adaptable resources which are continuously molded and improved by student feedback.
ContributorsReasor, Drew Donn (Author) / Rajan, Subramaniam (Thesis director) / Hjelmstad, Keith (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2014-05
Description
The civil engineering curriculum includes the engineering fields of environmental, geotechnical, hydrology, structural, and transportation. A particular focus on the structural engineering curriculum outline involves courses in mathematics, engineering mechanics, structural analysis, and structural design. The core structural analysis and design course at Arizona State University (CEE 321) is a transition course to connect realistic structural design and analysis concepts to an engineering foundation created by the first and second year mathematics and mechanics courses. CEE 321 is styled after a flipped classroom model and students are assessed through quizzes, midterms, design projects, and a final exam. Student performance was evaluated for the Spring 2013 and Fall 2013 semesters through an error analysis technique designed to categorize student mistakes based on type of error and related topic. This analysis revealed that student's basic engineering mechanics skills improved throughout the course as well as identified the areas that students struggle in. The slope-deflection and direct stiffness methods of analysis and calculating cross-sectional properties are the primary areas of concern. Using appropriate technology in the engineering classroom has the potential to enhance the learning environment and address the areas of inadequacy identified by the performance analysis. A survey of CEE 321 students demonstrated that technology is a highly integrated and useful portion of student's lives. Therefore, the engineering classroom should reflect this. Through the use of analysis and design software, students are able to begin to develop design intuition and understanding while completing realistic engineering projects in their third year of undergraduate studies. Additionally, incorporating internet resources into and outside of the classroom allows students to be connected to course content from any web-enabled device of their choice. Lecture videos posted online covering the course content were requested by many CEE 321 students and are an emerging resource that supplements the flipped classroom model. The availability of such a tool allows students to revisit concepts that they do not understand or pause, rewind, and replay the lectures when necessary. An expansion of the structural analysis and design online lecture videos for CEE 321 are expected to address and improve the areas that students struggle in as identified by the error analysis.
ContributorsMika, Krista Nicole (Author) / Rajan, Subramaniam (Thesis director) / Mamlouk, Michael (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2013-12