Matching Items (1,023)

Filtering by

Clear all filters

133797-Thumbnail Image.png

Development and Evaluation of an Electrical Engineering and Math Curriculum Module for High School Students

Description

Parents in STEM careers are more apt to guide their kids towards STEM careers (Sherburne-Michigan, 2017). There are STEM programs and classes for students who are interested in related fields, but the conundrum is that students need to be interested

Parents in STEM careers are more apt to guide their kids towards STEM careers (Sherburne-Michigan, 2017). There are STEM programs and classes for students who are interested in related fields, but the conundrum is that students need to be interested in order to choose to participate. The goal of this creative project was to introduce engineering concepts in a high school class to reveal and investigate the ways in which engineering concepts can be successfully introduced to a larger student populace to increase interest in engineering programs, courses, and degrees. A lesson plan and corresponding materials - including circuit kits and a simulated ball launching station with graphical display - were made to accomplish this goal. Throughout the lesson students were asked to (1) use given materials to accomplish a goal, (2) predict outcomes based on conceptual understanding and mathematical calculations, (3) test predictions, (4) record data, and (5) analyze data to generate results. The students first created a simple circuit to understand the circuit components and learn general electrical engineering concepts. A simple light dimmer circuit let students demonstrate understanding of electrical concepts (e.g., voltage, current resistance) before using the circuit to a simulated motor in order to launch a ball. The students were then asked to predict the time and height of a ball launched with various settings of their control circuit. The students were able to test their theories with the simulated launcher test set up shown in Figure 25 and collect data to create a parabolic height versus time graph. Based on the measured graph, the students were able to record their results and compare calculated values to real-world measured values. The results of the study suggest ways to introduce students to engineering while developing hands-on concept modeling of projectile motion and circuit design in math classrooms. Additionally, this lesson identifies a rich topic for teachers and STEM education researchers to explore lesson plans with interdisciplinary connections to engineering. This report will include the inspiration for the product, related work, iterative design process, and the final design. This information will be followed by user feedback, a project reflection, and lessons learned. The report will conclude with a summary and a discussion of future work.

Contributors

Agent

Created

Date Created
2018-05

132563-Thumbnail Image.png

Analog-to-Digital Converter Reliability Testing in Hostile Environments

Description

Analog to Digital Converters (ADCs) are a critical component in modern circuit applications. ADCs are used in virtually every application in which a digital circuit is interacting with data from the real world, ranging from commercial applications to crucial military

Analog to Digital Converters (ADCs) are a critical component in modern circuit applications. ADCs are used in virtually every application in which a digital circuit is interacting with data from the real world, ranging from commercial applications to crucial military and aerospace applications, and are especially important when interacting with sensors that observe environmental factors. Due to the critical nature of these converters, as well as the vast range of environments in which they are used, it is important that they accurately sample data regardless of environmental factors. These environmental factors range from input noise and power supply variations to temperature and radiation, and it is important to know how each may affect the accuracy of the resulting data when designing circuits that depend upon the data from these ADCs. These environmental factors are considered hostile environments, as they each generally have a negative effect on the operation of an ADC. This thesis seeks to investigate the effects of several of these hostile environmental variables on the performance of analog to digital converters. Three different analog to digital converters with similar specifications were selected and analyzed under common hostile environments. Data was collected on multiple copies of an ADC and averaged together to analyze the results using multiple characteristics of converter performance. Performance metrics were obtained across a range of frequencies, input noise, input signal offsets, power supply voltages, and temperatures. The obtained results showed a clear decrease in performance farther from a room temperature environment, but the results for several other environmental variables showed either no significant correlation or resulted in inconclusive data.

Contributors

Agent

Created

Date Created
2019-05

132421-Thumbnail Image.png

Predicting Mechanical Failure of Vacuum Pumps Using Accelerometer Data

Description

The objective of this paper is to find and describe trends in the fast Fourier transformed accelerometer data that can be used to predict the mechanical failure of large vacuum pumps used in industrial settings, such as providing drinking water.

The objective of this paper is to find and describe trends in the fast Fourier transformed accelerometer data that can be used to predict the mechanical failure of large vacuum pumps used in industrial settings, such as providing drinking water. Using three-dimensional plots of the data, this paper suggests how a model can be developed to predict the mechanical failure of vacuum pumps.

Contributors

Agent

Created

Date Created
2019-05

132515-Thumbnail Image.png

Around the Corner Imaging: Developing a Graphical User Interface

Description

This Creative Project was carried out in coordination with the capstone project, Around the Corner Imaging with Terahertz Waves. This capstone project deals with a system designed to implement Around the Corner, or Non Line-of-Sight (NLoS) Imaging. This document discusses

This Creative Project was carried out in coordination with the capstone project, Around the Corner Imaging with Terahertz Waves. This capstone project deals with a system designed to implement Around the Corner, or Non Line-of-Sight (NLoS) Imaging. This document discusses the creation of a GUI using MATLAB to control the Terahertz Imaging system. The GUI was developed in response to a need for synchronization, ease of operation, easy parameter modification, and data management. Along the way, many design decisions were made ranging from choosing a software platform to determining how variables should be passed. These decisions and considerations are discussed in this document. The resulting GUI has measured up to the design criteria and will be able to be used by anyone wishing to use the Terahertz Imaging System for further research in the field of Around the Corner or NLoS Imaging.

Contributors

Created

Date Created
2019-05

131314-Thumbnail Image.png

Automatic Recording of Children's Activity Within a Classroom: A Study of Levy Flights

Description

The diagnosis for an attention deficit/hyperactivity disorder (ADHD) in children is heavily based on teacher or parent opinion, and not on scientific evidence. This causes children to be wrongly diagnosed with a disorder and be prescribed medicine that they do

The diagnosis for an attention deficit/hyperactivity disorder (ADHD) in children is heavily based on teacher or parent opinion, and not on scientific evidence. This causes children to be wrongly diagnosed with a disorder and be prescribed medicine that they do not need to be taking. This paper discusses a project that was completed for the Child Study Lab (CSL) preschool at Arizona State University (ASU), in which children’s activity within a classroom was automatically recorded using ultra-wideband technology. This project’s goal was to gather location data on the children in the CSL and analyze and assess the collected data for any patterns of behavior. The hope was that if a child’s data displayed a pattern that strayed from the norm, that this analysis could pose as a more objective way to indicate that a child may have an attention deficit problem. Fractal Dimensions and Levy Flights were researched and applied to the data analysis portion of this project.

Contributors

Agent

Created

Date Created
2020-05

134362-Thumbnail Image.png

Optimization of Front Contact Design on Nickel-Plated Si Solar Cells

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,

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.

Contributors

Agent

Created

Date Created
2017-05

134465-Thumbnail Image.png

The Evolution of Social Media: Its Effect on Various Facets of Society

Description

Social media has evolved so quickly in the past two decades and continues to grow and change at a rapid pace. This way of connecting and communicating with others has become so ingrained in daily life and can have a

Social media has evolved so quickly in the past two decades and continues to grow and change at a rapid pace. This way of connecting and communicating with others has become so ingrained in daily life and can have a major influence on people's actions. Social media and social networking look vastly different today than it did in the past, and will continue to change for the future. The sports and travel industries are no exception to the integration of social media. Both entities understand the importance of being prominent in the online domain and connecting to the Millennial generation. It is crucial for young people to learn how to positively use social media in the classroom and in the workplace as their lives become consumed by this digital world. The emphasis on social media in different facets of society can bring both positive and negative connotations along with it, depending on how, when, and why people decide to use it. Social media is not meant to replace all interactions and forms of contact, but rather enhance these relationships. By analyzing the history of social media, current trends and effects, this project seeks to forecast the impact that social media will continue to have in the future. In the fast paced world today, social media and other forms of electronic communication will only continue to increase and be intensified. This project explores how social media has impacted society, most importantly, the travel industry and the sports industry. Social media will continue to expand knowledge, connect people all over the world, and enhance experiences as it inevitably becomes even more integrated into everyday life.

Contributors

Agent

Created

Date Created
2017-05

134611-Thumbnail Image.png

A Review of Gallium Nitride HEMTs to Improve CubeSat EPS Efficiency

Description

This paper reviews several current designs of Cube Satellite (CubeSat) Electrical Power Systems (EPS) based on Silicon FET technologies and their current deficiencies, such as radiation-incurred defects and switching power losses. A strategy to fix these is proposed by the

This paper reviews several current designs of Cube Satellite (CubeSat) Electrical Power Systems (EPS) based on Silicon FET technologies and their current deficiencies, such as radiation-incurred defects and switching power losses. A strategy to fix these is proposed by the way of using Gallium Nitride (GaN) High Electron-Mobility Transistors (HEMTs) as switching devices within Buck/Boost Converters and other regulators. This work summarizes the EPS designs of several CubeSat missions, classifies them, and outlines their efficiency. An in-depth example of an EPS is also given, explaining the process in which these systems are designed. Areas of deficiency are explained along with reasoning as to why GaN can mitigate these losses, including its wide bandgap properties such as high RDS(on) and High Breakdown Voltage. Special design considerations must be kept in mind when using GaN HEMTs in this application and an example of a CubeSat using GaN HEMTs is mentioned. Finally, challenges ahead for GaN are explored including manufacturing considerations and long-term reliability.

Contributors

Agent

Created

Date Created
2017-05

134612-Thumbnail Image.png

Cryogenic Testing of Microwave Kinetic Inductance Detectors (MKIDs)

Description

We designed and constructed a cryostat setup for MKID detectors. The goal for the cryostat is to have four stages: 40K, 4K, 1K and 250mK. Prior to the start of my thesis, the cryostat was reaching 70K and 9K on

We designed and constructed a cryostat setup for MKID detectors. The goal for the cryostat is to have four stages: 40K, 4K, 1K and 250mK. Prior to the start of my thesis, the cryostat was reaching 70K and 9K on the first and second stages respectively. During the first semester of my thesis I worked on getting the second stage to reach below 4K such that it would be cold enough to add a sorption fridge to reach 250mK. Various parts were machined for the cryostat and some tweaks were made to existing pieces. The largest changes were we thinned our stainless steel supports from 2mm to 10mil and we added roughly 6-10 layers of multi-layer insulation to the first and second stages. Our result was that we now reach temperatures of 36K and 2.6K on the first and second stages respectively. Next we added the sorption fridge to the 4K stage by having the 4K stage remachined to allow the sorption fridge to be mounted to the stage. Then I designed a final, two stage, setup for the 1K and 250mK stages that has maximum capabilities of housing a six inch wafer for testing. The design was sent to a machinist, but the parts were unfinished by the end of my thesis, so the parts and stage were not tested. Once the cryostat was fully tested and proven to reach the necessary temperatures, preliminary testing was done on a Microwave Kinetic Inductance Detector (MKID) provided by Stanford. Data was collected on the resonance and quality factor as they shifted with final stage temperature (5K to 285mK) and with input power (60dB to 15dB). The data was analyzed and the results agreed within expectations, as the resonant frequency and quality factor shifted down with increased temperature on the MKID. Finally, a noise characterization setup was designed to test the noise of devices, but was not fully implemented.

Contributors

Agent

Created

Date Created
2017-05

All About Solar

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.

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.

Contributors

Agent

Created

Date Created
2017-05