Physical Sciences and Mathematics Commons^™

Optimal Error Estimate Of Upwind Scheme On Adaptive Grid For Two Parameter Singular Perturbation Problem, J. Mohapatra, M. K. Mahalik

Applications and Applied Mathematics: An International Journal (AAM)

A singularly perturbed convection-diffusion problem with two small parameters is considered. The problem is solved by an upwind finite difference operator on an appropriate non-uniform mesh constructed adaptively by equi-distributing a monitor function based on the solution. An error bound in the maximum norm is established theoretically with the error constants shown to be independent of both singular perturbation parameters. The normalized flux obtained via interpolating the polynomial from the numerical solution is also uniformly convergent. A numerical experiment illustrates in practice the result of convergence proved theoretically.

A Semi-Parametric Approach For Analyzing Longitudinal Measurements With Non-Ignorable Missingness Using Regression Spline, Taban Baghfalaki, Saeide Sefidi, Mojtaba Ganjali

Applications and Applied Mathematics: An International Journal (AAM)

In longitudinal studies with missingness, shared parameter models (SPM) provide appropriate framework for the joint modeling of the measurements and missingness process. These models use a set of random effects to account for the interdependence between two processes. Sometimes the longitudinal responses may not be fitted well by using a linear model and some non-parametric methods have to be used. Also, parametric assumptions are typically made for the random effects distribution, and violation of those may affect the parameter estimates and standard errors. To overcome these problems, we propose a semi-parametric model for the joint modelling of longitudinal markers and …

Mathematical Modeling Of Two-Dimensional Unsteady Flow In Growing Tumor, N. Gracia, D. N. Riahi, R. Roy

Applications and Applied Mathematics: An International Journal (AAM)

We investigate the problem of unsteady fluid flow in growing solid tumors. We develop a mathematical model for a growing tumor whose boundary is taken as a sphere, and the unsteady fluid flow within the tumor is assumed to be two dimensional with respect to the radial distance and the latitudinal angle in spherical coordinates. The expressions for the time, radial and latitudinal variations of the flow velocity, pressure, and the two investigated drug concentrations within the tumor were determined analytically. We calculated these quantities in the tumor as well as in a corresponding normal tissue. We find, in particular, …

On The Stability Of A Three Species Syn-Eco-System With Mortality Rate For The Third Species, B. H. Prasad

Applications and Applied Mathematics: An International Journal (AAM)

The system comprises of a commensal (S₁) common to two hosts S₂ and S₃ with mortality rate for the host (S₃). Here all the three species posses limited resources. The model equations constitute a set of three first order non-linear simultaneous coupled differential equations. Criteria for the asymptotic stability of all the eight equilibrium states are established. Trajectories of the perturbations over the equilibrium states are illustrated. Further the global stability of the system is established with the aid of suitably constructed Liapunov’s function and the numerical solutions for the growth rate equations are …

Mathematical Model: Comparative Study Of Thermal Effects Of Laser In Corneal Refractive Surgeries, Gokul Kc, Dil B. Gurung, Pushpa R. Adhikary

Applications and Applied Mathematics: An International Journal (AAM)

Lasers have been widely used in ophthalmology. Refractive errors are some of the most common ophthalmic abnormalities worldwide. Laser refractive surgery was developed to correct refractive errors myopia, hyperopia and astigmatism. Two types of laser surgical techniques: lamellar and thermal are available to reshape the corneal curvature. Ultraviolet (UV) emitting argon fluoride (ArF) excimer laser is used to sculpt cornea in lamellar procedures, whereas, infrared (IR) emitting holmium yttrium aluminum garnet (Ho: YAG) laser is used to shrink cornea in thermal procedure. Tissue heating is common in all types of laser surgical techniques. Hence, in this paper, a finite element …

Nanoparticle Biofunctionalization For Self-Assembly And Energy Transfer Applications, Kaitlin Jeanne Coopersmith

Dissertations - ALL

Metal and semiconductor nanocrystals (NCs) have unique optical and physical properties that are dependent on size, composition and morphology. When NCs are coupled to biomolecules, their properties are combined to create unique materials with biomimetic capabilities that can function as biosensors, cellular imaging agents or drug delivery vehicles. Most NCs are synthesized in air free, non-polar conditions, so surface chemistries must be tuned to accommodate hydrophilic biomolecules. This can be achieved through ligand exchange or polymer encapsulation procedures. This work takes advantage of both phase transfer routes to functionalize gold nanoparticles (AuNPs), quantum dots (QDs), and quantum rods (QRs) with …

N3lo Calculations For Top-Quark Differential Cross Sections Near Partonic Threshold, Nikolaos Kidonakis

Faculty Articles

I present calculations of approximate corrections from NNLL soft-gluon resummation for total and differential cross sections in top-antitop pair production and single-top production in hadronic collisions. I show that soft-gluon corrections from partonic threshold are the dominant contribution to top-quark production and closely approximate exact results. I present aN3LO results for the total tt¯cross section, the top-quark pT and rapidity distributions, and the top-quark forwardbackward asymmetry. I also provide updates for single-top production in the t, s, and tW channels. Finally, I discuss top-quark production via anomalous gluon couplings.

Titanium Trisulfide Monolayer: Theoretical Prediction Of A New Direct-Gap Semiconductor With High And Anisotropic Carrier Mobility, Jun Dai, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

A new two-dimensional (2D) layered material, namely, titanium trisulfide (TiS₃) monolayer, is predicted to possess novel electronic properties. Ab initio calculations show that the perfect TiS₃ monolayer is a direct-gap semiconductor with a bandgap of 1.02 eV, close to that of bulk silicon, and with high carrier mobility. More remarkably, the in-plane electron mobility of the 2D TiS₃ is highly anisotropic, amounting to about 10,000 cm² V⁻¹ s⁻¹ in the b direction, which is higher than that of the MoS₂ monolayer, whereas the hole mobility is about two orders of magnitude lower. …

A Disk-Based Dynamical Mass Estimate For The Young Binary Ak Sco, I. Czekala, S. M. Andrews, Eric L.N. Jensen, K. G. Stassun, G. Torres, D. J. Wilner

Physics & Astronomy Faculty Works

We present spatially and spectrally resolved Atacama Large Millimeter/submillimeter Array (ALMA) observations of gas and dust in the disk orbiting the pre-main sequence (pre-MS) binary AK Sco. By forward-modeling the disk velocity field traced by CO J = 2-1 line emission, we infer the mass of the central binary, {M}_*=2.49+/- 0.10 {M}_☉ , a new dynamical measurement that is independent of stellar evolutionary models. Assuming the disk and binary are co-planar within ̃2°, this disk-based binary mass measurement is in excellent agreement with constraints from radial velocity monitoring of the combined stellar spectra. These ALMA results are …

A Transfer Function Based Frequency Model For Propagation Of A Chaos Wave Through Modified Von Karman Turbulence Under Various Chaos And Turbulence Conditions, Monish Ranjan Chatterjee, Fathi H.A. Mohamed

Electrical and Computer Engineering Faculty Publications

Complex phasor fields for electromagnetic wave propagation through von Karman turbulence and acousto-optic RF chaos are derived en route to the effective transfer function between chaos and narrow turbulence. Results are tested for several turbulence and chaos conditions.

Reliable Patch Trackers: Robust Visual Tracking By Exploiting Reliable Patches, Yang Li, Jianke Zhu, Steven C. H. Hoi

Research Collection School Of Computing and Information Systems

Most modern trackers typically employ a bounding box given in the first frame to track visual objects, where their tracking results are often sensitive to the initialization. In this paper, we propose a new tracking method, Reliable Patch Trackers (RPT), which attempts to identify and exploit the reliable patches that can be tracked effectively through the whole tracking process. Specifically, we present a tracking reliability metric to measure how reliably a patch can be tracked, where a probability model is proposed to estimate the distribution of reliable patches under a sequential Monte Carlo framework. As the reliable patches distributed over …

The Role Of Intermediary In Sustainable Lending: An Economic Analysis Of Crowdfunding Platform, Ling Ge, Zhiling Guo

Research Collection School Of Computing and Information Systems

Is the interest-free crowdfunding platform a promising alternative to the non-zero interest platform? This study investigates the lenders and borrowers’ incentives and choices between an indirect, non-zero interest rate platform intermediated by a field partner and a direct-lending, interest-free platform. We model the field partner as a profit maximizer that filters qualified borrowers to enable the lenders’ capital to be better utilized on the crowdfunding platform. We show that, under certain conditions, both the borrowers and lenders are better off from the existence of the field partner. The existence of field partner is necessary to effectively segment the market and …

Fire, Fuels, And Streams: The Effects And Effectiveness Of Riparian Treatments, Josh Mcdaniel

Joint Fire Science Program Digests

Fire is an important disturbance in riparian systems—consuming vegetation; increasing light; creating snags and debris flows; altering habitat structure; and affecting stream conditions, erosion, and hydrology. For many years, land managers have worked to keep fire out of riparian systems through the use of buffers. A number of projects funded by the Joint Fire Science Program are shedding light on the dynamics of fire in riparian systems. Recent research and field practice have shown that (1) riparian treatments can be beneficial and are not as risky as previously thought; and (2) riparian treatments need the “Goldilocks” prescribed fire—not too hot …

Investigating The Paleoecological Consequences Of Supercontinent Breakup: Sponges Clean Up In The Early Jurassic, Frank Corsetti, Kathleen Ritterbush, David Bottjer, Sarah Greene, Yadira Ibarra, Joyce Yager, A. Joshua West, William Berelson, Silvia Rosas, Thorsten Becker, Naomi Levine, Sean Loyd, Rowan Martindale, Victoria Petryshyn, Nathan Carroll, Elizabeth Petsios, Olivia Piazza, Carlie Pietsch, Jessica Stellmann, Jeffrey Thompson, Kirstin Washington, Dylan Wilmeth

Faculty Publications

The continued release of fossil fuel carbon into the atmosphere today means it is imperative to understand Earth system response to CO2 rise, and the geologic record offers unique opportunities to investigate such behavior. Stomatal and paleosol proxies demonstrate a large change in atmospheric pCO2 across the Triassic-Jurassic (T-J) transition, concomitant with the eruption and emplacement of the Central Atlantic Magmatic Province (CAMP) and the splitting of Pangea. As one of the “big 5” mass extinctions—when the so-called modern fauna was particularly hard hit—we know the biosphere was severely affected during this time, but the details are relatively poorly understood, …

Optimizations For Rendering Realistic Lens Flares In Polynomial Optics, Stephen Dilorio

Honors Theses

Lens flare is a common optical phenomenon exhibited by lens systems, like those used for professional photography or film. As light travels from the front of a lens system towards the sensor at the back, it can either refract through or reflect off of the surfaces of the lenses. A lens flare is the result of (typically) unwanted reflections and scattering caused by imperfections in the lenses. This reflected or scattered light then travels to the sensor following unexpected paths. While considered by some to be degrading artifacts, lens flares have grown to become an essential ingredient for realistic imagery …

Electrical Characterization Of Nanomaterials, Chase Martin

Honors Theses

Our dependence on energy sources and depleting fossil fuel reserves are forcing the world to look for efficient and renewable sources of energy. Current renewable technology lacks the efficiency and storage capability necessary to continue our heavy reliance on energy. This project focuses on understanding the physical and electrical properties of nanomaterials for their use as super capacitors and as photovoltaic cells. Using multiple microscopy techniques on the Cascade Probe Station and Veeco Dimension V Atomic Force Microscope, local and bulk conductivity measurements were performed on Laponite RD infused polyaniline (PANI) samples synthesized by Union College Chemistry Department Students. Four …

Partial Differential Equations, Nathaniel James Onnen

Honors Theses

This paper will discuss methods for solving many different partial differential equations, as well as real world applications in physics. We are interested in finding solutions to the wave and heat equations in one dimension, the wave equation in two dimensions, as well as a solution to Schrodinger’s equation. In order to do this, we will study different methods including Fourier series, Bessel functions, and Hermite polynomials. I will use these methods to derive solutions for the mentioned problems, as well as to produce visualizations for many of them.

Controlling Carbon: A Study Of National And Regional Emissions Trading Systems, Jordan Pulling

Honors Theses

The release of carbon and other chemicals into the atmosphere is a growing environmental problem. The use of carbon-based processes is at an all-time high with the continued growth in carbon-fueled transportation, electric power generation and other carbon-intensive industrial processes. With climate change increasingly threatening the daily lives of Earth's population, many countries are beginning to take steps to reduce their impact on the Earth and its climate. Over the last decade, carbon markets have been established in 18 countries worldwide. While all of these emissions trading systems have similarities, each also has some unique traits, including differences in allowance …

The Sylow Theorems And Classification Of Small Finite Order Groups, William Stearns

Honors Theses

This thesis will provide an overview of various topics in group theory, all in order to accomplish the end goal of classifying all groups of order up to 15. An important precursor to classifying finite order groups, the Sylow Theorems illustrate what subgroups of a given group must exist, and constitute the first half of this thesis. Using these theorems in the latter sections we will classify all the possible groups of various orders up to isomorphism. In concluding this thesis, all possible distinct groups of orders up to 15 will be defined and the groundwork set for further study.

Remote Water Metering In Venecia, Nicaragua, Jeffrey Wettstein

Honors Theses

The senior Capstone Design Project is the culmination of over three years of undergraduate work in electrical engineering, and other related fields. The project allows students to demonstrate their knowledge on a tangible design. Starting from a blank slate, the Capstone process asks students to carefully move through every stage of design in order to create the most effect output. Water shortage is a major problem for the entire world including the United States, but particularly in developing countries like Nicaragua. The community of Venecia, Nicaragua has a unique water problem. Community members leave taps running in fear that if …

Sem-Edx Analysis Of Aerosol Samples, Xuanhan Zhao

Honors Theses

One of the important environmental issues in upstate New York is the acid rain problem in the Adirondack Mountains, which is associated with atmospheric aerosols. As a part of a systematic study to understand the transport, transformation, and effects of airborne pollutants in the Adirondack Mountains, we are performing an analysis of atmospheric aerosols collected at Piseco Lake. In previous work, we used proton induced X-ray emission (PIXE) [1] spectrometry to measure the concentrations of elements in aerosol samples as a function of the size of the particulate matter. The results of the PIXE analysis indicate significant concentrations of sulfur …

Food Habits Of Fall-Collected Age-0 Walleyes In Eastern South Dakota Gla- Cial Lakes, Benjamin J. Schall, Matthew J. Phayvanh, Jeffrey D. Grote, Daniel J. Dembkowski, Melissa R. Wuellner

The Prairie Naturalist

Food habits of age-0 fishes can influence their growth and survival prior to the first winter (Hoxmeier et al. 2006, Shoup and Wahl 2011). Ontogenetic diet shifts in juvenile piscivorous fishes result in a transition in consumption from zooplankton to macroinvertebrates and eventually fish throughout development (Mittelbach and Persson 1998). Certain food items may be more energetically beneficial to fishes than others as consumption of prey fishes may lead to faster growth rates of predators, decreased overwinter starvation, avoidance of competition, and reduced predation risk (Werner and Gilliam 1984). By the time age-0 walleyes (Sander vitreus) have reached lengths of …

West Nile Virus And Ferruginous Hawks (Buteo Regalis) In The Northern Great Plains, Shubham Datta, Jonathan A. Jenks, David E. Knudsen, Kent C. Jensen, Will M. Inselman, Christopher C. Swanson, Troy W. Grovenburg

The Prairie Naturalist

Emerging infectious diseases (EID) present significant threats to the conservation of global biodiversity (Daszak et al. 2000). Evaluating impacts (spatial, temporal and demographic) of EIDs on sensitive and declining wildlife populations is challenging because quantitative information is usually dependent on estimates rather than counts (Wobeser 2007) and mortality rates are seldom quantified with conventional monitoring (Naugle et al. 2005).

West Nile virus (WNv), a mosquito-borne Flavivirus (family Flaviviridae; Komar 2001), was discovered in northwest Uganda in 1937 (Smithburn et al. 1940). First encountered in the western hemisphere in New York in 1999 (Nash et al. 2001), WNv has become enzootic …

Habitat-Related Differences In Necroph- Ilous Species Composition: Implications For Resource Competition, Adrienne L. Conley, Elisabeth K. Jorde, Rachel E. Jorde, Lauren K. Yares, Kenzie K. Lee, Carrie L. Hall, Daniel R. Howard

The Prairie Naturalist

Competition for resources is one of the most important selective factors influencing the expression of life history traits in both plants and animals (Darwin 1859). In grasslands, competition for resources such as nutrients, water, and space often is constrained by stochastic processes (Axelrod 1985). Disturbance factors such as fire, grazing by large herbivores, and fluctuating climatic conditions tend to alter the structure and magnitude of competition for limited resources among grassland communities more frequently than in other ecosystems (Snaydon 1987, van der Maarel 1993). Vertebrate carrion is one important resource used by both plants and animals in grasslands, providing a …

Comparison Of Two Trap Net Designs For Sampling Muskellunge, Brian G. Blackwell, Todd M. Kaufman, Tyrel S. Moos, David O. Lucchesi

The Prairie Naturalist

Sampling adequate numbers of muskellunge (Esox masquinongy) is necessary to evaluate stocking success and to collect information on various population metrics (e.g., growth, condition, relative abundance). However, muskellunge are often difficult to sample with standard fish sampling gears. We collected muskellunge in trap nets of two different designs (large trap nets [1.5-m × 1.8-m frames, 1.5-m diameter hoops, double throated, single 1.5-m × 30.5-m lead and 19-mm knotless mesh] and small trap nets [0.9-m × 1.5-m frames, 0.9-m diameter hoops, single throat, single 0.9-m × 15.2-m lead and 19-mm knotted mesh]. We also estimated abundance of muskellunge (>600 mm …

Notes: Are Land-Use Changes Reflected In Diets Of Mourning Doves (Zenaida Macroura) In Eastern South Dakota, Joshua B. Smith, Troy W. Grovenburg, Matthew A. Perrion, Jason M. Augspurger, Trevor W. Bultje, Anna M. Robinson, Brandi L. Crider, Datta Shubham, Jonathan A. Jenks

The Prairie Naturalist

Food habits of the mourning dove (Zenaida macroura) have been extensively studied in the southern United States (McClure 1943, Korschgen 1958, Carpenter 1971) and consist primarily of vegetable matter throughout their range (Beckwith 1959). Diet studies in several states have indicated agricultural crops, specifically corn and wheat, were the most readily consumed plant seeds (Korshgen 1958, Carpenter 1971). Similarities observed in diets of doves were dependent on the agricultural crops available within the area. For example, in Missouri, some seasonal variability was documented suggesting doves forage based on food availability as much as by food preference (Korschgen 1958). However, in …

Inter- And Intra-Specific Interactions In Germination And Seedling Establishment Of Cheatgrass And Russian Wildrye, Erin K. Espeland

The Prairie Naturalist

Cheatgrass (Bromus tectorum) is an invasive species in the arid and semi-arid west of the USA, and is weedy in disturbed prairie landscapes. Perennial Russian wildrye (Psathyrostachys juncea) limits population growth of cheatgrass, but the mechanism is unclear. I conducted glasshouse and greenhouse experiments to test if intra- and interspecific competitive interactions of seeds and seedlings of cheatgrass and Russian wildrye were different across a geographic soil gradient with different cultivation legacies in eastern Montana, USA. Seed-seed interactions occurred in both species. Cheatgrass and Russian wildrye inhibited one another’s emergence in one edaphic condition in one experiment. Cheatgrass growth was …

Using Otolith Microchemistry To Classify Yellow Perch As Stocked Or Naturally Produced, Andrew K. Carlson, Matthew J. Ward, Brian D.S Graeb

The Prairie Naturalist

Fisheries managers routinely use stocking to supplement fish populations (Schramm and Piper 1995, Fisher 1996). Stocking eyed-eggs offers substantial cost savings compared to stocking fry and fingerlings (PFBC 2011); however, traditional stocking evaluation using oxytetracycline (OTC) marking of otoliths is ineffective for eyed-eggs of some species (e.g., yellow perch, [Perca fla- vescens]). Thus, there is a need for additional approaches to be able to classify fish as stocked or naturally produced. Fish otoliths are paired calcified structures in the inner ear that permanently deposit trace elements in proportion to water column concentrations (Campana 1999, Campana et al. 2000). Coupled with …

Bot Fly Infestation Of Thirteen-Lined Ground Squirrels In Colorado Shortgrass Steppe, Kim Conway, Paul Stapp

The Prairie Naturalist

We studied prevalence of bot fly infestation of thirteen-lined ground squirrels (Ictidomys tridecemlineatus) trapped during 13 years of population monitoring in shrub and grassland habitats in northern Colorado. We also investigated effects of prescribed burning, a common habitat management practice in grasslands, on bot fly prevalence. Infested squirrels were rarely located on shrub sites and during spring (May–Jun) trapping. Across all summers, mean prevalence in grasslands was 7.9% (range: 2.1–23.8%), with years of highest prevalence corresponding to years when the fewest hosts were captured in spring. Infested squirrels had from one to seven warbles, with 46.7% having only one warble. …

Improving Communication Through Writing, Christopher N. Jacques

The Prairie Naturalist

Greetings GPNSS members! By the time you read this editorial, most of us will be enjoying the summer vacation and all that the Great Plains has to offer. Warmer temperatures, increasing day length, and time in the field are a welcomed change from the seemingly endless grip of “old man” winter (for those of us in the northern Great Plains). Of course, believing that anyone could truly enjoy the clouds of tormenting, biting insects and high humidity across the Great Plains is hard to imagine, in my opinion. There are plenty of summer activities for the outdoor enthusiasts among us, …