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Recent Submissions
Robert Moore's Thought on Optimal Human Psychological Development, and Walter J. Ong's Thought
(This version was not previously published., 2024) Farrell, Thomas
In my 3,669-word deeply personal and candid review essay "Robert Moore's Thought on Optimal Human Psychological Development, and Walter J. Ong's Thought," I highlight certain key points of the visionary thought of the later Jungian psychotherapist and theorist Robert Moore (1942-2016; Ph.D. in religion and psychology, University of Chicago, 1975) of the Chicago Theological Seminary. In addition, I highlight certain key points of the historical thought of the late American Jesuit Renaissance specialist and cultural historian and pioneering media ecology theorist Walter J. Ong (1912-2003; Ph.D. in English, Harvard University, 1955) of Saint Louis University -- where I took five courses from him over the years.
Minutes: Board of Regents: July 10, 2024
(University of Minnesota, 2024-07-10) University of Minnesota Board of Regents
Dockets: Board of Regents: July 10-12, 19, and 22, 2024
(University of Minnesota, 2024-07) University of Minnesota Board of Regents
Temperature Observations of the Twin Cities Canopy-Layer Urban Heat Island
(2024-10-10) Smoliak, Brian V; Snyder, Peter K; Twine, Tracy E; Mykleby, Phillip M; Hertel, William F; Liess, Stefan; liess@umn.edu; Liess, Stefan; Department of Soil, Water, and Climate
Data from a dense urban meteorological network (UMN) are analyzed, revealing the spatial heterogeneity
and temporal variability of the Twin Cities (Minneapolis–St. Paul, Minnesota) canopy-layer urban heat island
(UHI). Data from individual sensors represent surface air temperature (SAT) across a variety of local climate
zones within a 5000-km2 area and span the 3-yr period from 1 August 2011 to 1 August 2014. Irregularly
spaced data are interpolated to a uniform 1-km x 1-km grid using two statistical methods: 1) kriging and
2) cokriging with impervious surface area data. The cokriged SAT field exhibits lower bias and lower RMSE
than does the kriged SAT field when evaluated against an independent set of observations. Maps, time series,
and statistics that are based on the cokriged field are presented to describe the spatial structure and magnitude
of the Twin Cities metropolitan area (TCMA) UHI on hourly, daily, and seasonal time scales. The average
diurnal variation of the TCMA UHI exhibits distinct seasonal modulation wherein the daily maximum occurs
by night during summer and by day during winter. Daily variations in the UHI magnitude are linked to
changes in weather patterns. Seasonal variations in the UHI magnitude are discussed in terms of land–
atmosphere interactions. To the extent that they more fully resolve the spatial structure of the UHI, dense
UMNs are advantageous relative to limited collections of existing urban meteorological observations. Dense
UMNs are thus capable of providing valuable information for UHI monitoring and for implementing and
evaluating UHI mitigation efforts.
Microfluidic Experiments and Numerical Simulations of Inertia-induced Mixing and Reaction Maximization in Laminar Porous Media Flows
(2024-10-10) Chen, Michael; Lee, Sanghyun; Kang, Peter; pkkang@umn.edu; Kang, Peter; Kang Research Group
Solute transport and biogeochemical reactions in porous and fractured media flows are controlled by mixing, as are subsurface engineering operations such as contaminant remediation, geothermal energy production, and carbon sequestration. A porous media flow is generally regarded as slow, so the effects of fluid inertia on mixing and reaction are typically ignored. Here, we demonstrate through microfluidic experiments and numerical simulations of mixing-induced reaction, that inertial recirculating flows readily emerge in laminar porous media flows and dramatically alter mixing and reaction dynamics. An optimal Reynolds number that maximizes the reaction rate is observed for individual pore throats of different sizes. This reaction maximization is attributed to the effects of recirculation flows on reactant availability, mixing, and reaction completion, which depend on the topology of recirculation relative to the boundary of the reactants or mixing interface. Recirculation enhances mixing and reactant availability, but a further increase in flow velocity reduces the residence time in recirculation, leading to a decrease in reaction rate. The reaction maximization is also confirmed in a flow channel with grain inclusions and a randomized porous media. Interestingly, the domain-wide reaction rate shows a dramatic increase with increasing Re in the randomized porous media case. This is because fluid inertia induces complex three-dimensional flows in a randomized porous media, which significantly increases transverse spreading and mixing. This study shows how inertial flows control reaction dynamics at the pore scale and beyond, thus having major implications for a wide range of environmental systems.