Doctor of Philosophy

dissertationAdults are participating in all levels of higher education in increasing numbers due to a variety of societal, cultural, technological, and economic pressures. While many adult students attend 2-year colleges and technical institutions, 4-year colleges and universities are also enrolling substantial percentages of adult students. Nevertheless, adult college students - those who are functionally independent, have substantial work/life experience, and must balance school demands with extra-institutional obligations - experience low persistence and graduation rates comparative to their nonadult peers at these institutions. The literature on student retention points to the importance of academic integration for adult students. In recent years, student engagement - or participation in a variety of effective educational practices linked to successful outcomes - has been presented as an alternative formulation of academic integration. Prior research points to the importance of student engagement as a critical influence on student retention. The National Survey of Student Engagement [NSSE] measures engagement on five different benchmarks whose relevance for adult students is verified by the adult learning theory literature. This study utilizes data from the 2005 NSSE and correlational research methods to create an operationally useful definition of adult students and to compare their engagement on each of the five benchmarks to that of their nonadult peers. The findings are then explored to suggest refinements to current theory and practice and directions for future research regarding adult students

Four-dimensional laser induced fluorescence study of the structure of molecular mixing in turbulent flows

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77075/1/AIAA-1994-820-515.pd

A scalar imaging velocimetry technique for fully resolved four‐dimensional vector velocity field measurements in turbulent flows

This paper presents an experimental technique for obtaining fully resolved measurements of the vector velocity field u(x,t) throughout a four‐dimensional spatiotemporal region in a turbulent flow. The method uses fully resolved four‐dimensional scalar field imaging measurements in turbulent flows [Phys. Fluids A 3, 1115 (1991)] to extract the underlying velocity field from the exact conserved scalar transport equation. A procedure for accomplishing this is described, and results from a series of test cases are presented. These involve synthetically generated scalar fields as well as actual measured turbulent flow scalar fields advected numerically by various imposed flow fields. The imposed velocity fields are exactly known, allowing a careful validation of the technique and its potential accuracy. Results obtained from a zeroth iteration of the technique are found to be very close to the exact underlying vector velocity field. Further results show that successive iterations bring the velocity field from the zeroth iteration even closer to the exact result. It is also shown that the comparatively dense velocity field information that this technique provides is well suited for accurate extraction of the more dynamically insightful strain rate and vorticity fields ϵ(x,t) and ω(x,t).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69930/2/PFADEB-4-10-2191-1.pd

Direct, high resolution, four‐dimensional measurements of the fine scale structure of Sc≫1 molecular mixing in turbulent flows

Results from highly resolved, four‐dimensional measurements of the fine structure of the fully space‐ and time‐varying Sc≫1 conserved scalar field and the associated scalar energy dissipation rate field in a turbulent flow are presented. The resolution achieved in all three spatial dimensions and in time reaches down to the local strain‐limited molecular diffusion scale in the flow, allowing all three components of the instantaneous scalar gradient vector field ∇ζ(x,t) and their time evolution at every point in the data space to be directly evaluated. Results are presented in the form of fine structure maps of the instantaneous dissipation field loge ∇ζ⋅∇ζ(x,t) in several spatially adjacent data planes within an individual three‐dimensional spatial data volume, as well as in several temporally successive data planes from a sequence of such three‐dimensional data volumes. The degree of anisotopy in the underlying scalar gradient field is characterized in terms of the joint distribution β(ϑ,φ) of spherical orientation angles. The probability density of true scalar energy dissipation rates is presented and compared with the distributions that would result from lower‐dimensional measurements of the scalar gradient vector. From this the ‘‘spottiness’’ of the scalar dissipation field is directly quantified by determining the true fraction of the total dissipation that occurs in any given volume fraction of the flow.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70449/2/PFADEB-3-5-1115-1.pd

The acoustic characteristics of turbomachinery cavities

Internal fluid flows are subject not only to self-sustained oscillations of the purely hydrodynamic type but also to the coupling of the instability with the acoustic mode of the surrounding cavity. This situation is common to turbomachinery, since flow instabilities are confined within a flow path where the acoustic wavelength is typically smaller than the dimensions of the cavity and flow speeds are low enough to allow resonances. When acoustic coupling occurs, the fluctuations can become so severe in amplitude that it may induce structural failure of engine components. The potential for catastrophic failure makes identifying flow-induced noise and vibration sources a priority. In view of the complexity of these types of flows, this report was written with the purpose of presenting many of the methods used to compute frequencies for self-sustained oscillations. The report also presents the engineering formulae needed to calculate the acoustic resonant modes for ducts and cavities. Although the report is not a replacement for more complex numerical or experimental modeling techniques, it is intended to be used on general types of flow configurations that are known to produce self-sustained oscillations. This report provides a complete collection of these models under one cover

DomSVR: Domain boundary prediction with support vector regression from sequence information alone

Protein domains are structural and fundamental functional units of proteins. The information of protein domain boundaries is helpful in understanding the evolution, structures and functions of proteins, and also plays an important role in protein classification. In this paper, we propose a support vector regression-based method to address the problem of protein domain boundary identification based on novel input profiles extracted from AA-index database. As a result, our method achieves an average sensitivity of ∼36.5% and an average specificity of ∼ 81% for multi-domain protein chains, which is overall better than the performance of published approaches to identify domain boundary. As our method used sequence information alone, our method is simpler and faster.© Springer-Verlag 2010

Discipline-Specific Compared to Generic Training of Teachers in Higher Education

A recurrent theme arising in the higher education sector is the suitability and effectiveness of generic versus discipline-specific training of university teachers, who are often recruited based on their disciplinary specialties to become teachers in higher education. We compared two groups of participants who had undergone training using a generic post-graduate certificate in higher education (PGCertGeneric) versus a discipline-specific course in veterinary education (PGCertVetEd). The study was conducted using a survey that allowed comparison of participants who completed PGCertGeneric (n=21) with PGCertVetEd (n=22). Results indicated that participants from both PGCertGeneric and PGCertVetEd considered teaching to be satisfying and important to their careers, valued the teaching observation component of the course, and identified similar training needs. However, the participants of the PGCertVetEd felt that the course made them better teachers, valued the relevance of the components taught, understood course design better, were encouraged to do further courses/reading in teaching and learning, changed their teaching as a result of the course, and were less stressed about teaching as compared to the PGCertGeneric participants (p<.05). It is likely that the PGCertVetEd, which was designed and developed by veterinarians with a wider understanding of the veterinary sector, helped the participants perceive the training course as suited to their needs