Physical Sciences and Mathematics Commons^™

Conflict-Free Vertex Coloring Of Planar Graphs, Shawn Seymour

Scholarly Horizons: University of Minnesota, Morris Undergraduate Journal

The conflict-free coloring problem is a variation of the vertex coloring problem, a classical NP-hard optimization problem. The conflict-free coloring problem aims to color a possibly proper subset of vertices such that there is a unique color within the closed neighborhood (a vertex and its neighbors) of every vertex. This paper presents recent findings and heuristics to solve the conflict-free coloring problem on both general graphs and planar graphs.

Touchscreen Smartphone User Interfaces For Older Adults, Ai Sano

Scholarly Horizons: University of Minnesota, Morris Undergraduate Journal

Today the world is experiencing the rapid growth of the older population. The number of older adults who own digital devices such as smartphones is increasing as well. The current smartphone user interfaces, however, appear not optimized for older adults. When designing smartphone user interfaces for older adults, we must consider their age-related physical and cognitive changes, which most likely affect their user experience. The present paper explores smartphone user interface guidelines for older adults and heuristics for evaluating the usability of Android launchers for older adults as well as a research study that developed an Android launcher for older …

Identifying Twitter Spam By Utilizing Random Forests, Humza S. Haider

Scholarly Horizons: University of Minnesota, Morris Undergraduate Journal

The use of Twitter has rapidly grown since the first tweet in 2006. The number of spammers on Twitter shows a similar increase. Classifying users into spammers and non-spammers has been heavily researched, and new methods for spam detection are developing rapidly. One of these classification techniques is known as random forests. We examine three studies that employ random forests using user based features, geo-tagged features, and time dependent features. Each study showed high accuracy rates and F-measures with the exception of one model that had a test set with a more realistic proportion of spam relative to typical testing …

An Overview Of Modern Global Illumination, Skye A. Antinozzi

Scholarly Horizons: University of Minnesota, Morris Undergraduate Journal

Advancements in graphical hardware call for innovative solutions, which can improve the realism of computer generated lighting. These innovative solutions aim to generate state of the art computer generated lighting through a combination of intelligent global illumination models and the use of modern hardware. The solution described in this paper achieves global illumination by ray tracing over geometry within a 3D scene from distributed light field probes and proceeds to shade the scene with a deferred renderer. Such a solution provides the flexibility and robustness that many other global illumination models have previously lacked while still achieving realistic lighting that …

Artin L-Functions Of Small Conductor, John W. Jones, David P. Roberts

Mathematics Publications

We study the problem of finding the Artin L-functions with the smallest conductor for a given Galois type. We adapt standard analytic techniques to our novel situation of fixed Galois type and obtain much improved lower bounds on the smallest conductor. For small Galois types we use complete tables of number fields to determine the actual smallest conductor.

Stay Safe Online!, Jenny Blaine

Innovate! Teaching with Technology Conference

Inform audience of potential online threats to their online security and reasons for that; empower audience to employ best practices to protect themselves during online activities.

Multiple Audiences

Paper Or Plastic? A Comparison Of The Carbon Emissions Of Grocery Bags, Hannah Tuomi

Undergraduate Research Symposium 2017

Paper and plastic grocery bags, as well as reusable bags (non-woven polypropylene), all can be used to carry out purchases from the store. While these different bag types serve essentially the same function, how do their environmental impacts differ? One way to measure environmental impact is by examining a bag’s entire life cycle. A product’s life cycle encompasses various stages starting with the extraction of raw materials, going through production and then use, and ending with a waste management option (e.g. landfill or recycling). Life cycle assessment is a tool to evaluate one or more impact areas of a product …

Toward The Development Of A 10be Chronology Of Glaciation In The Mosquito Range, Colorado: A Progress Report, Noah Bensen, Keith A. Brugger

Undergraduate Research Symposium 2017

The Last Glacial Maximum (LGM) in the Rocky Mountain region occurred about 21 ka (20,000 years before present). However, dated glacial chronologies suggest that while LGM glacier advances in individual ranges in Colorado were somewhat synchronous, retreat from their maximum extents was asynchronous, varying between ~20 and 15 ka or later. The precise timing and spatial variation of glacier advance and retreat provides insights into LGM climate change and is necessary to calibrate climate models. To better understand the timing of the LGM in the Mosquito Range in Colorado, we collected 12 samples from granitic boulders on moraine crests in …

Investigation Of Hkust-1 And Related Composites With Protein Adsorption, Ramitha Rupasinghe

Undergraduate Research Symposium 2017

Metal Organic Frameworks (MOFs) possess well-ordered porous structures that have been shown to adsorb proteins. MOFs can be enhanced by combining them with suitable materials to make composites. Enhancements include, but are not limited to, changing pore sizes, adding functional groups, improving selectivity of adsorption, and increasing stability. Previous research has shown high adsorption of proteins by the MOF, HKUST-1 but no research has been done to investigate the adsorption by its related composites, such as HKUST-1/GO, HKUST-1/ magnetite and HKUST-1/magnetite/GO. In this research, HKUST-1 and composites based on graphene oxide (GO) and magnetite were synthesized, characterized by FTIR, XRD …

Hurwitz Number Fields, David P. Roberts

Mathematics Publications

The canonical covering maps from Hurwitz varieties to configuration varieties are important in algebraic geometry. The scheme-theoretic fiber above a rational point is commonly connected, in which case it is the spectrum of a Hurwitz number field. We study many examples of such maps and their fibers, finding number fields whose existence contradicts standard mass heuristics.

The Philosophy And Physics Of Time Travel: The Possibility Of Time Travel, Ramitha Rupasinghe

Honors Capstone Projects

Time travel to the past is an alluring subject for many science fiction writers but is it really science fiction or is there a way to make it happen, possibly in the distant future? In the world of physics, time travel to the future has already been accomplished but time travel to the past seems to be a subject of controversy. Similarly, both philosophers and physicists cannot completely agree on one fundamental question about time: what is it? In this interdisciplinary project, I will explore the fundamental nature of time as a building block to help me understand time travel. …

Transcription Through The Eye Of A Needle: Daily And Annual Cyclic Gene Expression Variation In Douglas-Fir Needles, Peter Dolan

Computer Science Publications

Background: Perennial growth in plants is the product of interdependent cycles of daily and annual stimuli that induce cycles of growth and dormancy. In conifers, needles are the key perennial organ that integrates daily and seasonal signals from light, temperature, and water availability. To understand the relationship between seasonal cycles and seasonal gene expression responses in conifers, we examined diurnal and circannual needle mRNA accumulation in Douglas-fir (Pseudotsuga menziesii) needles at diurnal and circannual scales. Using mRNA sequencing, we sampled 6.1 × 109 reads from 19 trees and constructed a de novo pan-transcriptome reference that includes 173,882 tree-derived transcripts. Using …