Master's Degree Culminating Works

Persistent link for this collection

https://conservancy.umn.edu/handle/11299/209910

This collection contains works created by UMD graduate students for master's degrees from programs based at UMD. It includes theses (for "Plan A" thesis-based master's degrees), projects (for "Plan B" project-based master's degrees), and papers (for "Plan C" coursework-based master's degrees).

Please note: Additional theses (not Plan B project papers or Plan C papers) can be found in the University of Minnesota Twin Cities Dissertations and Theses collection.

To see final works for specific graduate degrees, click the links below. (Some of these graduate programs have been discontinued.)

Browse

Now showing 1 - 20 of 859

(1+1) Evolutionary Algorithm on Random Planted Vertex Cover Problems
(2024-03) Kearney, Jack
Evolutionary Algorithms are powerful optimization tools that use the power of randomness and inspiration from biology to achieve results. A common combinatorial optimization problem is the recovery of a minimum vertex cover on some graph 𝐺 = (𝑉, 𝐸). In this work, an evolutionary algorithm will be employed on specific instances of the minimum vertex cover problem containing a random planted solution. This situation is common in data networks and translates to a core set of nodes and larger fringe set that are connected to the core. This study introduces a parameterized analysis of a standard (1+1) Evolutionary Algorithm applied to the random planted distribution of vertex cover problems. When the planted cover is at most logarithmic, restarting the (1+1) EA every 𝑂(𝑛 log 𝑛) steps will, within polynomial time, yield a cover at least as small as the planted cover for sufficiently dense random graphs (𝑝 > 0.71). For superlogarithmic planted covers, the (1+1) EA is proven to find a solution within fixed-parameter tractable time in expectation. To complement these theoretical investigations, a series of computational experiments were conducted, highlighting the intricate interplay between planted cover size, graph density, and runtime. A critical range of edge probability was also investigated.
A 10,000-year lake-sediment based reconstruction of precipitation isotope values in the Canadian Rocky Mountains and implications for past changes in North American hydroclimate
(2019-01) Wagner, Zachary
Hydroclimate change in the Canadian Rocky Mountains is an important area of research, as demand for water resources in the Great Plains has been continuously increasing in recent years. The population of Alberta has one of the fastest growth rates in Canada, and cities like Calgary and Edmonton are dependent on surface and groundwater resources that originate from precipitation in the mountains. Recent increases in petroleum exploration have also amplified demands for water, along with the growing water requirements of industrial agriculture. The application of sound water resource management policies is essential, and historical records span only ~200 years, a time frame too short to capture the full range of climate variability. The development of paleoclimate proxy records from the Rocky Mountains is therefore necessary to attain a thorough perspective on potential changes in climate. Such data can, for example, inform water resource managers of possible shifts in precipitation seasonality and drought/pluvial events on timescales of decades to millennia. To this end, we present a 10,000-year oxygen isotope record as a proxy for precipitation seasonality linked to the Pacific North American pattern (PNA) which adds to a growing body of research in a region of high spatial complexity of hydroclimate. Shark Lake in Alberta, CA (50.8412°N, 115.3990°W; 1857 m above sea level) is a hydrologically open basin lake in the Canadian Rocky Mountains with one large outlet and numerous small inlets and groundwater springs. Winter precipitation is more depleted in the heavier 18O isotope relative to summer precipitation due to equilibrium fractionation from rain-out and phase changes. δ18O and δD values of Shark Lake water samples (collected during the summer) range from -18.9 to -20.0 ‰ and -141 to -150 ‰, respectively. The annual weighted average precipitation isotope ratios are -16.6 and -126 ‰ for oxygen and hydrogen, respectively. This indicates that Shark Lake principally receives water inputs from runoff or shallow groundwater that originated as precipitation during the cold season. We collected 1 m and 1.5 m long sediment cores using a modified Livingstone corer and used loss-on-ignition (LOI), x-ray diffraction (XRD), x-ray fluorescence (XRF) analyses to destermine sediment texture and composition. The sediment was dated using 14C from terrestrial plant fossils, as well as 210Pb and 137Cs for the surface sediment. We analyzed the isotopic composition (δ18O) of authigenic carbonate sediment from Shark Lake using mass spectrometry and applied these results as a proxy for precipitation seasonality. Lake water oxygen isotope ratios are captured by authigenic carbonates, which form during the spring and summer in response to pH changes associated with primary production. These carbonate minerals (calcite) precipitate in isotopic equilibrium and are deposited on the lakebed where they are preserved. The Shark Lake δ18O record demonstrates a transition from lower to higher average δ18O values from the middle to the late-Holocene at around 4500 yr BP. This is consistent with previous findings of changes in PNA-like atmospheric patterns during the middle Holocene, when a gradual shift from a more negative to a more positive mean state phase of the PNA occurred. This produced enhanced zonal atmospheric circulation in the Pacific Basin that led to a reduction in winter precipitation in northwestern North America and drier conditions in the southwestern part of the continent in the late Holocene relative to the middle Holocene. The Shark Lake δ18O record has a positive, significant correlation with other similar records from the Pacific Northwest, specifically those from Lime Lake (WA) and the OCNM (OR) speleothem, and has a negative, significant correlation with records from the southern Rocky Mountains and eastern North America, namely those from Bison Lake (CO), Cheeseman Lake (NL), Grinnell Lake (NJ), and the Buckeye Creek Cave speleothems (WV). Decadally resolved records are useful for tracking changes in PNA state and its interaction with other related climate oscillations such as the El Niño Southern Oscillation (ENSO) and the associated Pacific Decadal Oscillation (PDO). Open-basin lake records can also be combined with hydrologically closed-basin lake records to reconstruct pluvial and drought periods over the Holocene. The Shark Lake record increases the spatial resolution of mid- to late Holocene hydroclimate climate data in the Rocky Mountains and provides a baseline for natural variability in precipitation seasonality in a hydrologically important region.
A 2000 Year Sub-annual Record of Climate Change from Lake Malawi
(2009-08) Petrick, Benjamin Fredericks
Lake Malawi, in East Africa, provides a rare opportunity to look at a sub-annual record of climate change from a region were there is a lack of good climate records. This is possible because the upper most sediments in the north basin Lake Malawi are varved. The varved record extends from back 1200-2000 years depending on dating differences and is well dated back 800 years. In order to construct an overall sub-annual record of climate change, overlapping sections of two cores from the north basin of Lake Malawi taken during the recent Malawi drilling project were examined on a scanning XRF with a step size of .2 mm. This provided an average of 6 measurements per annual varve couplet. Because of the chemical differences between light and dark varves it was possible to count these varves using a high resolution photograph and x-radiography images in conjunction with the chemical data. Four major chemical elements or ratios of chemical element were used to represent the four major components in the sediments of the core: Fe is a proxy for the clay, Si/Ti is a proxy for the Biogenic Silica (BSi, inc/coh scattering ratio is a proxy for %Total Organic Carbon (TOC), and K/Ti is a proxy for volcanic sediments. Comparing Fe to recent records of lake level fall and rise suggests that Fe be when the planktonic community is dominated by diatoms it reflects changes in year to year fluvial input. However at times of change in the planktonic community, the Fefluvial imput relationship breaks down. Comparisons of both the lake level records and to coral records from the Indian Ocean show that both lake level rise and fall are enhanced by increased ocean temperatures over periods of 5-10 years. This suggests that changes in Indian Ocean temperatures have an affect on Lake Malawi. The lake records show no connection to Zimbabwe rainfall but an opposite relationship with Indian rainfall. The inc/coh shows a strong relationship over the last 150 years with IOD and proportion of diatoms in the planktonic community, which tends to change during times with great IOD variability. These relationships suggest that IOD causes changes in the winds that stimulate production of planktonic during the dry season. Looking further back in the record shows that similar shifts to non-diatom dominated planktonic community occurred twice before in the record and there is some evidence in the record that changes in winds might be responsible for these events as well. 11 year and 3-7 year cycles were also found in the record but their meaning is unclear. The times when the 11 year cycle is strong in the lake are not assonated with the record of sunspots and the 3 to 7 year cycle does not seem to be related to changes in ESNO as would be expected. Therefore the meaning of the cycles is still not understood. The longer record suggests dry periods from the bottom of the varved section to around 1250 AD and from 1550 to 1650 AD, with an interceding wetter period from 1250 to 1650 AD. The record from 1650 AD to current day shows some rises and falls and an overall steady record. Comparing this to other records of African lakes and caves shows that this record has similarities to the records of East African lakes but is in opposite of records from Cold Air Cave in Southern Africa. Lastly it also shows similarities to records of Indian monsoon wind strength which is controlled by Indian Ocean temperatures and Cariaco basin records which are a proxy for the ITCZ. Both of these records show that the migration of the ITCZ and changes in Indian Ocean temperatures are important drivers for Lake Malawi and the findings of this paper may be useful in looking at changes both at longer time scales and in the future as well.
210Pb Geochronology in Lake Superior Sediments: Sedimentation Rates, Organic Carbon Deposition, Sedimentary Environments, and Post-Depositional Processes
(1980-07) Evans, James Erwin
210Pb geochronology is used to determine sedimentation rates, 210Pb flux rates, and organic carbon deposition rates from 17 sediment box cores in Lake Superior, U.S.A. These data, in conjunction with organic carbon, PCB, trace metal, benthic organism, and sedimentary structure data, are used to investigate depositional and postdepositional processes. Sedimentation rates vary from 0.01-0.20 cm/yr in Lake Superior. A dynamic model is presented which emphasizes: (1) very high (greater than 0.15 cm/yr) sedimentation rates in marginal bays, (2) moderate to very high (0.07-0.19 cm/yr) open lake sedimentation rates in regions adjacent to marginal bays, these regions are affected by plumes of suspended sediment that originate in marginal bays by wave-stirring of bottom sediments, and enter the open lake, (3) moderate to high (0.05-0.11 cm/yr) sedimentation rates adjacent to the Red Clay Area, where shoreline recession rates are high, (4) moderate to high (0.05-0.12 cm/yr) sedimentation rates in the deepest portions of the Lake Superior Troughs region, with downslope sediment movement off the adjacent shoals and into the troughs, (5) low to moderate (0.04-0.05 cm/yr) sedimentation rates from cores with current bedding features in the Keweenaw Current region, and (6) very low (0.01-0.03 cm/yr) sedimentation rates in the central lake basins due to isolation from sediment sources. Organic carbon deposition rates (K) range from 0.0001 to 0.0032 g Carbon/cm2/yr, and K varies as a power function of sedimentation rate W (g/cm2/ yr) such that K = 0.04 W1.03. This result may imply that higher sedimentation rates favor organic carbon preservation with rapid removal from the oxidizing conditions at the sediment-water interface through burial. However, the exponent is very close to 1.00, which implies that a constant proportion of organic matter is deposited with sedimentation at any site. Calculations using primary productivity measurements and average K values indicate that about 77-87% of primary production carbon is oxidized in the water column during deposition. The 210 Pb flux rate P (dpm/cm2/ yr) is directly related to the organic carbon deposition rate, such that K = 4 x 10-4P. This indicates that the main transfer mechanism for 210Pb through the water column is via association with organic particles. Organic carbon concentrations (C) decline exponentially with increasing sediment age from surficial values of 1-5% to "background" values of 0.5% in 9,000 year old sediment. The decay phenomena can be described by C = C0 e-λt, with values for the decay constant (λ) ranging from 0.2 to 1.7 x 10 -2/yr. These decay constants are 2 to 3 orders of magnitude higher than the oceans, probably due to the presence of younger and more chemically reactive organic components in Lake Superior sediments. The sedimentation rate (W) is inversely related to the decay constant (λ), such that λ = 5.33 x 10 -4 w -0.53. This may indicate that rapid burial promotes organic matter preservation. Independent evidence for biological mixing of Lake Superior sediments includes surficial zones of constant 210Pb activity, the presence of PCB substances below the sediment horizon corresponding to its first usage in commercial quantities, benthic organism studies, and lack of lamination in the upper portions of cores on x-radiographs. Oligochaete displacement rates are calculated which equal or exceed sediment accumulation rates in many cores. This indicates that oligochaetes cause significant sediment mixing at some sites. At other sites, additional mixing by burrowing amphipods may increase sediment mixing. Mixing is considered as a mechanistic analogue to diffusion phenomenon, and mixing (eddy diffusion) coefficients are calculated (Db = 0.002-10.54 cm2/yr). The highest of these compare to other studies from lakes and nearshore marine regions, while the lowest compare to rates from abyssal regions. Zones of constant 210Pb activity at depth in the sediment correspond to the time intervals 1900-1910, 1910-1920, and 1940-1950. These are interpreted as storm deposit layers, and may correspond to major storms which occurred in the Lake Superior region during November 27-28, 1905, November 22-24, 1918, and November 10-12, 1940. Diagenetic horizons are described from the sediments, these include 1-2 mm thick black laminations, 1.0-1.5 cm thick orange-colored "crusts", and layers 3-5 cm thick of many 1-2 mm diameter micronodules. The available evidence indicates that the black laminations are Mn enrichments and the orange-colored crusts may be Fe enrichments.
A 40,000 year geochemical record from Lake Chalco, Mexico.
(2012-04) Pierce, Megan Leigh
Water balances of Southwestern North America and of northern South America are dependent on positions of the North American (Mexican) Monsoon and the ITCZ respectively. The North American Monsoon leads to significant summer rainfall across a broad swath of the continent, and constitutes the major source of annual precipitation over the southwestern United States and northern Mexico. The position of the ITCZ and the strength of the accompanying monsoon are affected by variability in insolation. Northern hemisphere cooling results in a southerly displacement of both the ITCZ and North American Monsoon, whereas northern hemisphere warming results in a more northward position. The Basin of Mexico can be potentially impacted by both of these systems. A new geochemical climate record from Lake Chalco, Mexico, which couples inorganic (X-ray fluorescence) and organic (biomarkers and stable isotopes) geochemical proxies, reconstructs external forcings of volcanism and aridity over the past 40,000 years, as well as ecosystem responses to these forcings. The Basin of Mexico is a high altitude closed lacustrine basin (20ºN, 99ºW; 2240 m.a.s.l.) in the Trans Mexican Volcanic Belt. The relict paleolake, Lake Chalco, is located near Mexico City in the southern sub-basin, and has an area of 120 km2 and a catchment of 1100 km2. Though the present-day lake has been reduced to a small marsh due to historic diversion of its incoming rivers; over longer timescales the lake has been a sensitive recorder of hydroclimatic variations in the neotropics. Low Ca concentrations indicate greater aridity during the late glacial relative to the last interstadial or early Holocene. Peaks in Fe concentrations indicate volcanism and the deposition of tephra throughout the last 40ka, with more frequent episodic volcanism occurring in the most recent 23ka. N-alkane biomarkers, compound specific carbon isotopes, and XRF data provide evidence for ecosystem responses to both aridity and volcanism. The extent to which both of these external forcings affected ecosystem is assessed; and the extent to which global or local external forcings affect the Basin of Mexico is addressed.
Abusive Supervision and Burnout: The Moderating Role of Subordinates’ Neuroticism and Time Spent with the Supervisors
(2020-05) Yu, Jie
Drawing on Conservation of Resources theory (COR. Hobfoll, 1989), the purpose of this study was to further our understanding of the relationship between abusive supervision and burnout by testing the moderating effects of subordinates' neuroticism and time spent with the supervisor. Data collected from two samples showed that there was a positive and significant relationship between abusive supervision and burnout. When considering only the primary moderator, subordinates' neuroticism, on the relationship abusive supervision and burnout, the perception of abusive supervision on burnout was not influenced by any level of subordinates' neuroticism. When considering the primary moderator (subordinates' neuroticism) and secondary moderator (time spent with the supervisor) on the relationship between abusive supervision and burnout, results from Sample 2 only found a significant three-way interaction between abusive supervision, subordinates' neuroticism, and time spent with supervision that was operationalized as time spent interacting with the supervisor in hours per week. Specifically, the positive relationship between abusive supervision and burnout was strongest when subordinates were high neuroticism and they interacted with their supervisor for more than 9.45 hours a week. Practical implications, limitations and future directions are discussed.
Academic Achievement of 8th Grade Students Who Were Retained Once in Elementary School
(1966-06) Brown, Margaret M Roby
Academic Achievement of Students in Special Education in a Socially Inclusive School
(2018-05) James, Peter J
The purpose of this study was to investigate the extent to which students with disabilities achieved academic growth in a school setting that emphasizes the importance of all students becoming full members of the classroom and school communities. The participants were 22 students who were students in the school's Special Education program for at least four years. As its basis for assessing academic growth, the study examined the reading and mathematics percentile rankings of Northwest Evaluation Association's (NWEA) Measures of Academic Progress (MAP) assessments conducted in the students' first and last years of enrollment in the school's Special Education program. The study found that nearly all students showed percentile growth in both reading and mathematics assessments, that the growth was independent of gender or the number of years in the school's Special Education program, and that students achieved, on average, higher than 50th percentile results on nationally-normed assessments of reading and mathematics.
Academic Stereotypes and Asian Students in the College Classroom
(2015-09) Park, Bridget E
This thesis project explores the student and faculty experience(s) of Asian stereotypes in a regional Midwestern university setting. Data was collected through one-on-one interviews with students—both Asian and non-Asian—and faculty of the university. Interviews were then transcribed and analyzed for emerging themes on three tiers: individually, within the interviewee's group (i.e. Asian student, non-Asian student, or faculty), and across all groups. Major themes included Asian stereotypes in the media and in pop culture, language-related stereotypes of Asians, Asian academic stereotypes (e.g. attitudes toward school, performance, etc.), and stereotypes concerning how Asian students socialize. These themes were presented from a faculty viewpoint and student viewpoints, which included Asian and non-Asian students. After discussing the emergent themes, implications for students, faculty, and university administration are addressed.
Academically Dismissed Students: A Perplexing Problem
(2010) Ramsey, Hilary B
New freshman students who participated in a mandatory freshman welcome week still landed in academic dismissal status. The researcher used an electronic survey tool sent to academically dismissed students who re-enrolled through Continuing Education, the department responsible for this student group. Despite the information about services and activities designed to build a connection with campus, students still do not utilize resources available to them. Major external factors that students struggled with were time management issues, stress and developing goodstudy skills. The surveyresults yield a student profile that indicates these students should have been successful but survey responses indicate multiple reasons they were not academically successful.
Achievement in the Arithmetic by Students Taught Traditionally Compared with Students Taught by a Modern Mathematics Program
(1963-08) Tompkins, Hazel M
Achievement of Talented Students in Homogeneous and Heterogeneous History Classes
(1959-08) Stark, Bruce N
Achieving Peak Flow and Sediment Loading Reductions through Increased Water Storage in the Le Sueur Watershed, Minnesota: A Modeling Approach
(2015-09) Mitchell, Nathaniel
Climate change, land clearing, and artificial drainage have increased the Minnesota River Basin’s stream flows and the rates at which channel banks and bluffs are eroded. Increasing erosion rates have contributed to higher sediment-loading rates, excess turbidity levels, and increases in sedimentation rates in Lake Pepin further downstream. These issues have motivated the discussion of flood management through either wetland restoration or the implementation of simple detention basins. This study uses the Soil and Water Assessment Tool (SWAT) to assess a wide variety of water retention site (WRS) implementation scenarios in the Le Sueur watershed in south-central Minnesota, a subwatershed of the Minnesota River Basin. Projected flows were used in conjunction with an empirical relationship developed from gauging data to assess changes in sediment-loading rates from near-channel features in the lower watershed. The WRS term is used as a general term for depressional storage areas, and sites could be made into wetlands or detention basins. Sites were delineated as topographic depressions with specific land uses, minimum areas (3000 m2), and relatively high compound topographic index (CTI) values. Contributing areas were manually measured for the WRS delineated. These contributing areas were used with existing depression depths, and different site characteristics to create 210 initial WRS scenarios. The contributing areas measured for the initial scenarios were used to create a generalized relationship between WRS area and contributing area. This relationship was used with different design depths, placement scenarios, and K values to create 225 generalized WRS scenarios. Reductions in peak flow volumes and sediment-loading rates are generally maximized by placing sites with high K values in the upper half of the watershed. High K values allow sites to lose more water through seepage, emptying their storages between precipitation events and preventing frequent overflowing. Reductions in peak flow volumes and sediment-loading rates also level off as WRS extent increases. This reduction in cost effectiveness with increasing site extent is due to the decreasing frequencies of high-magnitude events. The generalized WRS scenarios were used to create a simplified empirical model capable of generating peak flows and sediment-loading rates from near-channel features in the lower watershed. This simplified model is being incorporated into a decision-analysis model portraying a wide variety of management options in the Le Sueur watershed. This tool may better enable local stakeholders to evaluate, select, and promote management scenarios that best address the issues faced in the region.
Adinkra: Integration of African and Western Cultural Visual Vocabulary
(2005-05) Kumoji, Ida Korkor
This project is about the utilization of pictograms and ideograms based on Adinkra symbols and Western alphabets to create a visual language for cross cultural understanding. The project is about the integration of the Adinkra symbols and the Alphabet into a new visual medium. This medium will be a meeting place for both cultures. As a graphic designer, I am trying to create the new medium, introducing elements from different cultures to a new culture. This integration will respect both languages and the new language that is created will maintain the forms of each respective language. The purpose will be to familiarize people from Western and African culture with elements from both Adinkra symbols and the Alphabets in a friendly way. The project is designed to educate an audience like the visual artist, Graphic designers, Educators, Social, Cultural and Multicultural Studies, Language and Semiotics and Students.
Adolescent Patterns of Participation in Sherburne and Wright County 4-H
(2010) Rosendahl, Harlan; Rauschenfels, Diane; Hyman, Randy
Adolescent Patterns of Participation in Sherburne and Wright County 4-H was a replication study of the Tufts University study in 2005-2007 that measured the “5Cs” of positive youth development in young adolescents in grades 5, 6, and 7. This replication study was done with older adolescents in grades 10, 11, 12, and 13 in the Sherburne and Wright County 4-H program. The “5Cs” of positive youth development were connection, competence, character, caring, and confidence. The subjects rated questions about the “5Cs” in the survey. Roth (2004) suggested that positive youth development programs needed to increase the levels of the “5Cs" in the youth participating in the program. A product of a positive youth development program like 4-H, would be to instill the characteristics of the “5Cs” in youth. As youth develop these characteristics, they grow to become good citizens. This would be one way the 4-H program could provide public value. The results of this survey allowed comparisons to be made between the Tufts study and this study.
Adult Student Perceptions of Bullying and Interventions
(2016-05) Belisle, Ann M
The purpose of this study was to explore and understand the perspectives of adult students and their experiences with bullying and the effect this issue had for them personally. The focus of the study will seek to understand the adult students' perspectives and make the comparative analysis of these findings regarding the pervasiveness of bullying and the effect on academic achievement and social climate and where these students believe more focus needs to be. By collecting the perspectives of the students, continuing improvements can be made to current interventions of bullying; and thus improving educational experience for all students.
An Advanced Course of Study in Science for Upper-Elementary Students
(1961-08) Sloan, Charles Allen
Advantages and/or Disadvantages of the Various Approaches to Reading Used in the Elementary Schools of the Fort Frances - Rainy River Board of Education as Seen by Administrators
(1977-08) Ogden, Cecil L
The Amazing Composobot: Music Information Retreval and Algorithmic Composition
(2018-05) Walker, Marcus
Music has powerful and inscrutable effects on the human mind, and we are far from fully understanding how that magic works. But music is not random: there are patterns in the sounds and rhythms of a piece that can be analyzed, things that can be learned! In this work I will review relevant research on the subject of Music Information Retrieval and then introduce Composobot, an original program that incorporates and extends the lessons of that research. Together we will examine how Composobot prepares musical pieces for processing, analyzes them to extract systems of patterns and dependencies, and then composes novel musical pieces based on what it has learned. Finally, we will discuss how much of the magic that is in the music we love can be captured by learning patterns the way Composobot does, and how those methods might be tweaked to capture an even greater share of it.
American History: Developing Skills, Understanding Content, and Applying Knowledge: Curriculum
(2011) Winkle, Mark; Williams, Julia
This is an American History curriculum which in six units covers six distinct topics in American history from the time of Columbus arriving in the Bahamas through the Civil War. For most units, I have provided some suggested lessons and assessment pieces, as well as tips for navigating the lessons through some challenging issues. The curriculum doesn’t have complete lesson plans, or assessments, and it is not intended to be used as a textbook or teacher workbook. It’s intended to be a guide on how to teach American History in a way that focuses on students’ skills and on history’s usable lessons. I developed this curriculum while working with high schools students who were at-risk, and the lessons and activities reflect this as much of the work is done as a class, or while actively assisting students. However, the curriculum and lessons can easily be adapted to various ages and abilities. This curriculum is designed to make the study of American history an activity which builds the fundamental skills students need to be successful in school, in work, and as citizens.