Matching Items (6)

134932-Thumbnail Image.png

An Experimental Study of the Effect of Induction and Exhaust Systems on a Vehicle's Fuel Efficiency

Description

This thesis focuses on the effects of an engine's induction and exhaust systems on vehicle fuel efficiency, along with the challenges accompanying improvement of this parameter. The aim of the

This thesis focuses on the effects of an engine's induction and exhaust systems on vehicle fuel efficiency, along with the challenges accompanying improvement of this parameter. The aim of the project was to take an unconventional approach by investigating potential methods of increasing fuel economy via change of these systems outside the engine, as finding substantial gains via this method negates the need to alter engine architectures, potentially saving manufacturers research and development costs. The ultimate goal was to determine the feasibility of modifying induction and exhaust systems to increase fuel efficiency via reduction of engine pumping losses and increase in volumetric efficiency, with the hope that this research can aid others researching engine design in both educational and commercial settings. The first step toward achieving this goal was purchasing a test vehicle and performing experimental fuel efficiency testing on the unmodified, properly serviced specimen. A test route was devised to provide for a well-rounded fuel efficiency measurement for each trial. After stock vehicle trials were completed, the vehicle was to be taken out of service for a turbocharger system installation; unfortunately, challenges arose that could not be rectified within the project timeframe, and this portion of the project was aborted, to be investigated in the future. This decision was made after numerous fitment and construction issues with prefabricated turbo conversion parts were found, including induction and exhaust pipe size problems and misalignments, kit component packaging issues such as intercooler dimensions being too large, as well as manufacturing oversights, like failure to machine flanges flat for sealing and specification of incorrect flange sizes for mating components. After returning the vehicle to stock condition by removing the partially installed turbocharger system, the next step in the project was then installation of high-flow induction and exhaust systems on the test vehicle, followed by fuel efficiency testing using the same procedure as during the first portion of the experiment. After analysis of the quantitative and qualitative data collected during this thesis project, several conclusions were made. First, the replacement of stock intake and exhaust systems with high-flow variants did make for a statistically significant increase in fuel efficiency, ranging between 10 and 20 percent on a 95% confidence interval. Average fuel efficiency of the test vehicle rose from 21.66 to 24.90 MPG, an impressive increase considering the relative simplicity of the modifications. The tradeoff made was in noise produced by the vehicle; while the high-flow induction system only resulted in increased noise under very high-load circumstances, the high-flow exhaust system created additional noise under numerous load conditions, limiting the market applicability for this system. The most ideal vehicle type for this type of setup is sports/enthusiast cars, as increased noise is often considered a desirable addition to the driving experience; light trucks also represent an excellent application opportunity for these systems, as noise is not a primary concern in production of these vehicles. Finally, it was found that investing in high-flow induction and exhaust systems may not be a wise investment at the consumer level due to the lengthy payoff period, but for manufacturers, these systems represent a lucrative opportunity to increase fuel efficiency, potentially boosting sales and profits, as well as allowing the company to more easily meet federal CAFE standards in America. After completion of this project, there are several further research directions that could be taken to expand upon what was learned. The fuel efficiency improvements realized by installing high-flow induction and exhaust systems together on a vehicle were experimentally measured during testing; determining the individual effects of each of these systems installed on a vehicle would be the next logical research step within the same vein. Noise, vibration, and harshness increases after installing these systems were also noticed during experimental trials, so another future research direction could be an investigation into reducing these unwanted effects of high-flow systems. Finally, turbocharging to increase a vehicle's fuel efficiency, the original topic of this thesis, is another very important, contemporary issue in the world of improving vehicle fuel efficiency, and with manufacturers consistently moving toward turbocharged platform development, is a prime research topic in this area of study. In conclusion, the results from this thesis project exhibit that high-flow induction and exhaust systems can substantially improve a vehicle's fuel efficiency without modifying any internal engine components. This idea of improving a vehicle's fuel economy from outside the engine will ideally be further researched, such as by investigating turbocharger systems and their ability to improve fuel efficiency, as well as be developed and implemented by others in their educational projects and commercial products.

Contributors

Agent

Created

Date Created
  • 2016-12

150576-Thumbnail Image.png

Beginning chemistry teachers use of the triplet relationship during their first three years in the classroom

Description

Pedagogical content knowledge (PCK) has been described as the knowledge teachers' use in the process of designing and implementing lessons to a particular group of students. This includes the most

Pedagogical content knowledge (PCK) has been described as the knowledge teachers' use in the process of designing and implementing lessons to a particular group of students. This includes the most effective representations that make the content understandable to students, together with the preconceptions and misconceptions that students hold. For chemistry, students have been found to have difficulty with the discipline due to its reliance upon three levels of representation called the triplet: the macro, the submicro, and the symbolic. This study examines eight beginning chemistry teachers' depiction of the chemistry content through the triplet relationship and modifications as a result of considering students' understanding across the teacher's first three years in the classroom. The data collected included classroom observations, interviews, and artifacts for the purpose of triangulation. The analysis of the data revealed that beginning chemistry teachers utilized the abstract components, submicro and symbolic, primarily in the first year. However, the teachers began to engage more macro representations over time building a more developed instructional repertoire. Additionally, teachers' developed an awareness of and responded to their students' understanding of learning atomic structure during the second and third year teaching. The results of this study call for preservice and induction programs to help novice chemistry teachers build a beginning repertoire that focuses on the triplet relationship. In so doing, the teachers enter the classroom with a repertoire that allows them to address the needs of their students. Finally, the study suggests that the triplet relationship framework should be revisited to include an additional component that frames learning to account for socioscientific issues and historical contributions.

Contributors

Agent

Created

Date Created
  • 2012

151629-Thumbnail Image.png

Supporting first year alternatively certified urban and rural intern teachers through a multicomponent distance induction program

Description

The pathway for entering the K-12 classroom as a teacher varies compared to what was once the traditional model of teacher preparation. In this mixed-methods action research study, I explore

The pathway for entering the K-12 classroom as a teacher varies compared to what was once the traditional model of teacher preparation. In this mixed-methods action research study, I explore supporting first year alternatively certified urban and rural intern teachers through a multicomponent distance induction program. The induction model in this study was based on the theoretical framework of Bandura's social learning theory and Wenger's communities of practice. The purpose of this study was to identify the extent in which a multicomponent distance learning induction program impacts first year intern teachers' sense of self-efficacy, understand their successes, their challenges, and to identify how intern teacher evaluations change. Quantitative data included results from a self-efficacy survey and the Student Teaching Assessment Instrument (STAI). Qualitative data was collected through intern teachers' blogs, cadre leader video narratives, and cadre leader STAI narrative responses. Six themes emerged including topics such as building relationships with other education professionals, receiving feedback from the cadre leader, identifying struggles and application of college coursework into the K-12 classroom. Key findings reveal interns are least efficacious in student engagement, relationships with other educators support an intern teacher emotionally and pedagogically, intern teachers struggle with work-life balance, and cadre leaders observed intern teachers as having improved their skills in student engagement, instructional practices, and classroom management. Implications to practice include a structured approach to introducing student engagement, creating a best practices library of video examples, and a pre-orientation (Super Saturday) of topics prior to stepping into the classroom with students.

Contributors

Agent

Created

Date Created
  • 2013

150266-Thumbnail Image.png

The: impact of the social norms of education on beginning science teachers' understanding of NOS during their first three years in the classroom

Description

An understanding of the Nature of Science (NOS) remains a fundamental goal of science education in the Unites States. A developed understanding of NOS provides a framework in which to

An understanding of the Nature of Science (NOS) remains a fundamental goal of science education in the Unites States. A developed understanding of NOS provides a framework in which to situate science knowledge. Secondary science teachers play a critical role in providing students with an introduction to understanding NOS. Unfortunately, due to the high turnover rates of secondary science teachers in the United States, this critical role is often filled by relatively novice teachers. These beginning secondary science teachers make instructional decisions regarding science that are drawn from their emerging knowledge base, including a tentative understanding of NOS. This tentative knowledge can be affected by environment and culture of the classroom, school, and district in which beginning teachers find themselves. When examining NOS among preservice and beginning teachers the background and demographics of the teachers are often ignored. These teachers are treated as a homogenous block in terms of their initial understanding of NOS. This oversight potentially ignores interactions that may happen over time as teachers cross the border from college students, preservice teachers, and scientists into the classroom environment. Through Symbolic Interactionism we can explain how teachers change in order to adapt to their new surroundings and how this adaptation may be detrimental to their understanding of NOS and ultimately to their practice. 63 teachers drawn from a larger National Science Foundation (NSF) funded study were interviewed about their understanding of NOS over three years. Several demographic factors including college major, preservice program, number of History and Philosophy of Science classes, and highest academic degree achieve were shown to have an affect on the understanding of NOS over time. In addition, over time, the teachers tended to 'converge' in their understanding of NOS regardless of preservice experiences or induction support. Both the affect of different demographics amongst teachers and the 'converging' aspect of their understanding of NOS provide much needed insight for teacher trainers, mentors, and researchers.

Contributors

Agent

Created

Date Created
  • 2011

150804-Thumbnail Image.png

Beginning teachers' production of pedagogical content knowledge: a cultural historical perspective

Description

Few would argue that teacher effectiveness is a key lever in education reform and improving the overall quality of public education, especially in poor and working class communities. To that

Few would argue that teacher effectiveness is a key lever in education reform and improving the overall quality of public education, especially in poor and working class communities. To that end, the importance of supporting and developing beginning teachers is of utmost importance in education, thus requiring deep understandings of the process of learning to teach. Yet, most conceptions of teacher learning struggle to capture the social, cultural, and historical context of teacher learning, particularly in understanding how learning and the production of knowledge is situated, active, and complex. One example of this limitation comes from the field of research on pedagogical content knowledge (PCK) and its importance in developing effective beginning teachers. This study characterizes beginning teachers' production of PCK within a cultural historical activity theory (CHAT) framework. This study finds that the teachers produce PCK mostly based on their own individual experiences and reflections, receiving little assistance from the structures intended to provide them with support. The self-produced PCK is uneven, underdeveloped, and relies on teachers to use their sense of agency and identity to navigate dissonant and unbalanced activity systems. Over time, PCK production remains uneven and underdeveloped, while the individual teachers find it more and more difficult to bring balance to their activity systems, ultimately resulting in their exit from the activity system of teaching in their district and school.

Contributors

Agent

Created

Date Created
  • 2012

149853-Thumbnail Image.png

Miss [untitled]: learning to teach science to English language learners while navigating affordances and constraints : a longitudinal multiple case study

Description

ABSTRACT Early career science teachers are often assigned to classrooms with high numbers of English language learners (ELL students). As these teachers learn to become effective practitioners, the circumstances surrounding

ABSTRACT Early career science teachers are often assigned to classrooms with high numbers of English language learners (ELL students). As these teachers learn to become effective practitioners, the circumstances surrounding them merit a thorough examination. This study examines the longitudinal changes in Pedagogical Content Knowledge (PCK) and practices of six early career science teachers who taught in urban schools. The teachers participated in the Alternative Support for Induction Science Teachers (ASIST) program during their initial two years of teaching. Our research team followed the participants over a five-year period. This study focuses on data from Years 1, 3, and 5. The data collected included classroom observations and interviews. In addition, classroom artifacts were collected periodically for the purpose of triangulation. The analysis of the data revealed that with the support of the ASIST program, the teachers implemented inquiry lessons and utilized instructional materials that promoted academic language skills and science competencies among their ELL students. Conversely, standardized testing, teaching assignment, and school culture played a role in constraining the implementation of inquiry-based practices. The results of this study call for collaborative efforts among university science educators and school administrators to provide professional development opportunities and support for the implementation of inquiry and language practices among early career science teachers of ELL students.

Contributors

Agent

Created

Date Created
  • 2011