Physical Sciences and Mathematics Commons^™

A Survey Of Maximal K-Degenerate Graphs And K-Trees, Allan Bickle

Theory and Applications of Graphs

This article surveys results on maximal $k$-degenerate graphs, $k$-trees,

and related classes including simple $k$-trees, $k$-paths, maximal

outerplanar graphs, and Apollonian networks. These graphs are important

in many problems in graph theory and computer science. Types of results

surveyed include structural characterizations, enumeration, degree

sets and sequences, chromatic polynomials, algorithms, and related

extremal problems.

Easy, Bright, Fluorescence Demonstration Of Buffer Action, Mariana Dykstra, Yejin Chung, Mark Muyskens

University Faculty Publications and Creative Works

We report an attractive update to the demonstration of acid–base buffer action that is appropriate for ease of use and getting attention in the classroom. The twist is based on new fluorophore information and the recent availability of UV flashlights serving as an ideal, portable excitation light source. The pH-dependent fluorescence comes from a choice among three natural sources, namely narra tree wood extract, kidneywood extract, and scopoletin, which is a purchasable coumarin, that all perform equally well. We provide practical details for performing the buffer demonstration at scales of 100 and 1000 mL and give background information for context.

On The Exact Helium Wave Function Expansion, Ii, An Exponential Modulated Form, Carl W. David

Chemistry Education Materials

A 1¹S wave function’s expansion for 2 electron atoms and ions is proposed employing an appropriate exponential factor and Fock’s logarithmic terms. The leading coefficient’s are presented.

Joint Map Of Hardin County, Kentucky, Steven L. Martin, Emily Morris

Map and Chart--KGS

New field mapping of joints with previously published joint and fault locations. This fracture map can be used as a critical data source for hydrological, karst or geotechnical applications. Joint orientations were measured in 2009, 2022 and 2023, and are combined with joint and fault locations for Hardin County, Kentucky from 1:24,000-scale USGS geologic quadrangle maps that were published from 1962 to 1977. The geologic quadrangle maps for the county were digitized from 2002 to 2007.

The geology of Hardin County consists of Upper Devonian New Albany Shale overlain by Lower to Upper Mississippian-age sequences of limestone, dolomite, sandstone and …

Non-Hermitian Physics Achieved Via Non-Local Gilbert Damping, Trevor Joshua Macintosh

Electronic Theses and Dissertations

In this thesis, we study a simple model for a ferromagnet starting with Heisenberg exchange interaction including the effects of dissipation. Gilbert damping is consid- ered and generalized from an on-site term to include non-local damping interactions between neighbouring spins. The strength of the damping interaction between neigh- bours can be tuned individually to provide the freedom to change the parameters of the system and explore the range of possible non-Hermitian behaviours. We consider the example of a honeycomb lattice ferromagnet featuring Dirac cones and two sub- lattices and analyse the resulting spectra and eigenstates. Under periodic boundary conditions, we …

Parallels Of Quantum Superposition In Ecological Models: From Counterintuitive Patterns To Eco-Evolutionary Interpretations Of Cryptic Species, David G. Angeler, Hannah B. Fried-Petersen

School of Natural Resources: Faculty Publications

Background Superposition, i.e. the ability of a particle (electron, photon) to occur in different states or positions simultaneously, is a hallmark in the subatomic world of quantum mechanics. Although counterintuitive at first sight, the quantum world has potential to inform macro-systems of people and nature. Using time series and spatial analysis of bird, phytoplankton and benthic invertebrate communities, this paper shows that superposition can occur analogously in redundancy analysis (RDA) frequently used by ecologists.

Results We show that within individual ecosystems single species can be associated simultaneously with different orthogonal axes in RDA models, which suggests that they operate in …

Inventory Of Western United States Glaciers- 2020, Shrinidhi Ambinakudige, Bernard Abubakari

College of Arts and Sciences Publications and Scholarship

The dataset employed for delineating glacier boundaries in the Western United States comprises a compilation of original Sentinel-2 images obtained from the European Space Agency's Copernicus website. These images were instrumental in generating the glacier inventory. Additionally, the dataset includes a Python and R script specifically crafted for processing and classifying Sentinel images. The outcome of this process is represented in an ESRI shapefile, which contains an inventory of glaciers extracted from Sentinel images.

Water Whiplash In Mediterranean Regions Of The World, Citlalli Madrigal, Rama Bedri, Thomas Piechota, Wenzhao Li, Glenn Tootle, Hesham El-Askary

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The presence of weather and water whiplash in Mediterranean regions of the world is analyzed using historical streamflow records from 1926 to 2023, depending on the region. Streamflow from the United States (California), Italy, Australia, Chile, and South Africa is analyzed using publicly available databases. Water whiplash—or the rapid shift of wet and dry periods—are compared. Wet and dry periods are defined based on annual deviations from the historical record average, and whiplash occurs when there is an abrupt change that overcomes an accommodated deficit or surplus. Of all the stations, there are more dry years (56%) than wet years …

Superconductivity Of Amorphous And Crystalline Re–Lu Films, Serafim Teknowijoyo, Armen Gulian

Mathematics, Physics, and Computer Science Faculty Articles and Research

We report on superconducting properties of a novel material: rhenium-lutetium films. Different compositions of RexLu binary are explored from x ≈ 3.8 to close to pure Re stoichiometry. The highest critical temperature, up to 7 K, is obtained for x ≈ 10.5 in accordance with electron dispersive spectroscopy results. Depending on the deposition conditions, polycrystalline or amorphous films are obtainable, both of which are interesting for practical use. Crystalline structure of polycrystalline phase is identified as a non-centrosymmetric superconductor using grazing incidence x-ray diffractometry. Superconducting properties were characterized both resistively and magnetically. Magnetoresistivity and AC/DC susceptibility measurements allowed …

On Modeling Arterial Blood Flow With Or Without Solute Transport And In Presence Of Atherosclerosis, Daniel N. Riahi, Saulo Orizaga

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

In this article, we review previous studies of modeling problems for blood flow with or without transport of a solute in a section of arterial blood flow and in the presence of atherosclerosis. Moreover, we review problems of bio-fluid dynamics within the field of biophysics. In most modeling cases, the presence of red blood cells in the plasma is taken into account either by using a two-phase flow approach, where blood plasma is considered as one phase and red blood cells are counted as another phase, or by using a variable viscosity formula that accounts for the amount of hematocrit …

Controls On Plastic Debris Capture In Urban Stormwater Drains Of London, Canada: A Study Within The Great Lakes Watershed, Nina Kozikowski

Electronic Thesis and Dissertation Repository

Land-based sources are the greatest contributors of plastic pollution in aquatic environments. Prior to this investigation, there were no available studies concerning the number and types of plastic debris items between 1 mm and 5 mm captured in urban stormwater drains. The present study examined macroplastic (>5 mm) and large microplastic (1-5 mm) debris that accumulated in LittaTrap^TM devices at six drain sites over four seasonal periods in London, Ontario, Canada. Macroplastics (MaPs) and microplastics (MPs) were found in all 36 samples, and the totals ranged from 5-158 MaPs and 18-359 MPs per trap. Out of the 118 …

Digitizing Delphi: Educating Audiences Through Virtual Reconstruction, Kate Koury

The Journal of Purdue Undergraduate Research

Implementing a 3D model into a virtual space allows the general public to engage critically with archaeological processes. There are many unseen decisions that go into reconstructing an ancient temple. Analysis of available materials and techniques, predictions of how objects were used, decisions of what sources to reference, puzzle piecing broken remains together, and even educated guesses used to fill gaps in information often go unobserved by the public. This work will educate users about those choices by allowing the side-by-side comparison of conflicting theories on the reconstruction of the Tholos at Delphi, which is an ideal site because of …

Promises And Risks Of Applying Ai Medical Imaging To Early Detection Of Cancers, And Regulation For Ai Medical Imaging, Yiyao Zhang

The Journal of Purdue Undergraduate Research

No abstract provided.

The Impact Of Accessible Data On Cyberstalking, Elise Kwan

The Journal of Purdue Undergraduate Research

No abstract provided.

Model Selection Through Cross-Validation For Supervised Learning Tasks With Manifold Data, Derek Brown

The Journal of Purdue Undergraduate Research

No abstract provided.

The Effects Of Wildfire Aerosol Emissions On Air Quality, Emma Braun, Audrey Shirley

The Journal of Purdue Undergraduate Research

No abstract provided.

Upleft: Pick Up Leftovers, Uplift Those In Need, Veronica Galles

The Journal of Purdue Undergraduate Research

No abstract provided.

Characterizing Differential Reflectivity Calibration Dependence On Environmental Temperature Using The X-Band Teaching And Research Radar (Xtrra): Looking For A Relationship Between Temperature And Differential Reflectivity Bias, Emma Miller

The Journal of Purdue Undergraduate Research

Calibration scans are important for the maintenance of data and the quality of the information that radars output. In this study we looked for a temperature dependency in a full year’s worth of differential reflectivity (ZDR) calibration scan data collected by the X-band Teaching and Research Radar (XTRRA) located near the Purdue University campus. In a vertically pointing calibration scan, the radar scans the drops from below while rotating. From this angle, the overall shape will be circular, which corresponds to a ZDR value of approximately 0 dB. To process the data for the year 2021, a Python script was …

Machine Learning Of Big Data: A Gaussian Regression Model To Predict The Spatiotemporal Distribution Of Ground Ozone, Jerry Gu

The Journal of Purdue Undergraduate Research

Tracking pollution levels on the ground is important to the environment and public health. One of the pollutants of concern is ozone, which, at high concentrations, can cause respiratory and cardiovascular problems. The National Center for Atmospheric Research (NCAR) has published valuable ozone data obtained from ground-based sensors installed at selected locations. Because it is unfeasible to measure the exact ozone levels everywhere at any time, it would be valuable to predict the temporal-spatial distributions of ozone concentration based on existing data. This would help us better understand the patterns and trends in the data and make better decisions to …

A Computational Profile Of Invasive Lionfish In Belize: A New Insight On A Destructive Species, Joshua E. Balan

The Journal of Purdue Undergraduate Research

Since their discovery in the region in 2009, invasive Indonesian-native lionfish have been taking over the Belize Barrier Reef. As a result, populations of local species have dwindled as they are either eaten or outcompeted by the invaders. This has led to devastating losses ecologically and economically; massive industries in the local nations, such as fisheries and tourism, have suffered greatly. Attempting to combat this, local organizations, from nonprofits to ecotourism companies, have been manually spear-hunting them on scuba dives to cull the population. One such company, Reef Conservation Institute (ReefCI), operating out of Tom Owens Caye outside of Placencia, …

Clouds In The Ancient Lunar Atmosphere: Water Ice Nucleation On Aerosol Simulants, Mariana C. Aguilar

The Journal of Purdue Undergraduate Research

Today’s moon is vastly different from what it was 3 billion years ago. At that time, it was home to a collisional atmosphere formed through massive amounts of volcanism, releasing enough subsurface gas to sustain surface pressures of up to 1 kPa. Observations of our solar system have taught us that all dense atmospheres are host to clouds and aerosols, and we expect the Moon’s to be no different. Knowing when, where, and under what conditions cloud particles form is important for understanding the evolution of the lunar atmosphere, how it reacted to temperature gradients, and how it cycled volatiles. …

The Aim To Decentralize Economic Systems With Blockchains And Crypto, Mary Lacity

Arkansas Law Review

As an information systems (“IS”) professor, I wrote this Article for legal professionals new to blockchains and crypto. This target audience likely is most interested in crypto for its legal implications—depending on whether it functions as currencies, securities, commodities, or properties; however, legal professionals also need to understand crypto’s origin, how transactions work, and how they are governed.

Acknowledgement Of Reviewers

Journal of Sustainable Mining

No abstract provided.

Genesis Of Efficient Reservoirs In Mixed Sedimentary Setting: A Case Study Of Benxi Formation In The Gaoqiao Area, Ordos Basin, Shu Liu, Jinbu Li, Fengbo Jin, Haifeng Liu, Meng Wang, Yulin Cheng, Yulin Cheng, Xiaohong Zhong, Hao Lu

Turkish Journal of Earth Sciences

The Benxi-Taiyuan Formation in the southern region of the Ordos Basin represents a typical mixed sedimentary system, which has witnessed recent breakthroughs in the exploration of tight sandstone gas within the Benxi Formation. However, the development patterns of reservoirs in this mixed sedimentary area remain unclear, influenced by the sedimentary model and the distribution scale of sedimentary sandstone bodies. This study investigates the paleogeomorphology, sedimentary model, sandstone body type, petrological characteristics, and pore structure of the Benxi Formation. Field profiles, drilling core observations, microscopic section analysis, scanning electron microscopy (SEM), high-pressure mercury injection (HPMI), and physical property analysis are employed. …

Xlnet4rec: Modeling User’S Long-Term And Short-Term Interests In E-Commerce Recommender Systems, Namarta Vij

Electronic Theses and Dissertations

In e-commerce, a sequential recommender system is often used to predict the item that the user is likely to select next. This prediction can be used to create a recommender system to assist the user in making selections. However, when the user’s interests evolve over time, it becomes challenging to make such personalized recommendations. A more accurate recommender system thus needs to effectively interpret and adapt to a user’s changing interests by considering user’s long-term and short-term interests. Many attention-based methods focus on a user’s last clicked item to learn short-term interests. However, this approach may not consistently represent the …

A Survey On Training Challenges In Generative Adversarial Networks For Biomedical Image Analysis, Muhammad Muneeb Saad, Ruairi O'Reilly, Mubashir Husain Rehmani

Department of Computer Science Publications

In biomedical image analysis, the applicability of deep learning methods is directly impacted by the quantity of image data available. This is due to deep learning models requiring large image datasets to provide high-level performance. Generative Adversarial Networks (GANs) have been widely utilized to address data limitations through the generation of synthetic biomedical images. GANs consist of two models. The generator, a model that learns how to produce synthetic images based on the feedback it receives. The discriminator, a model that classifies an image as synthetic or real and provides feedback to the generator. Throughout the training process, a GAN …

Year-2 Progress Report On Numerical Methods For Bgk-Type Kinetic Equations, Steven M. Wise, Evan Habbershaw

Faculty Publications and Other Works -- Mathematics

In this second progress report we expand upon our previous report and preliminary work. Specifically, we review some work on the numerical solution of single- and multi-species BGK-type kinetic equations of particle transport. Such equations model the motion of fluid particles via a density field when the kinetic theory of rarefied gases must be used in place of the continuum limit Navier-Stokes and Euler equations. The BGK-type equations describe the fluid in terms of phase space variables, and, in three space dimensions, require 6 independent phase-space variables (3 for space and 3 for velocity) for each species for accurate simulation. …

Mineralogical And Geochemical Characteristics Of The Upper Cretaceous And Lower Paleocene Parts Of The Germav Formation: Southeastern Türkiye, Sema Teti̇ker

Turkish Journal of Earth Sciences

The mineralogical and chemical characteristics of Upper Cretaceous-Lower Paleocene claystone sediment samples taken from Mardin and Batman, located in southeastern Türkiye, were analyzed in the present study. The clay mineral paragenesis in the Upper Cretaceous units consisted of chlorite-smectite (C-S) and illite, whereas the Lower Paleocene unit consisted of chlorite-vermiculite (CV) and vermiculite minerals. Analyses conducted on clay samples indicated high levels of Al, Mg, Fe, Cr, V, Ni, and Zr. Low levels of alkali and alkaline earth elements (Mg, Na, Ca, K) in the clay-rich sediments suggest relatively high-grade weathering in the source area. The mineralogical compositions, major elemental …

Landslide Susceptibility Assessment Of The Asi Watershed, Southern Türkiye, Senem Teki̇n, Adolfo Quesada Román, Tolga Çan

Turkish Journal of Earth Sciences

Landslides constitute recurrent natural hazards worldwide with greater socioeconomic impacts in low-income places. Landslide susceptibility studies are carried out to determine the potential for landslides to occur in a region, to predict possible risks in the future and to integrate this information into sustainable planning and management strategies. Slip-type landslides occur in limited areas of less than 1% of the Asi watershed in Southern Türkiye. Therefore, meaningful estimations cannot be made with classical statistical models. So, using the maximum entropy approach (MaxEnt), a technique for estimating based on a small number of observations, a landslide susceptibility assessment was constructed. The …

An Experimental Investigation On The Discrete Poisson’S Upward Continuation Of Anomalous Gravity Field Data, Mehmet Si̇mav, Bi̇hter Erol, Muhammet Aki̇f Gülender, Serdar Erol

Turkish Journal of Earth Sciences

The Poisson upward continuation of gravity field functionals, typically given on the Earth’s irregular topography with limited spatial extent, necessitates some proper treatments due to the theoretical requirements. This study reviews the Poisson theory and investigates a more rigorous methodology for the numerical solution of the spherical integral equation by addressing many issues such as spherical-Earth model implementation, far-zone effect, Poisson kernel modification, and suitable ground data reduction scheme. We first explore the far-zone effect and search for an optimal near-zone spherical cap radius above which the truncation error is negligible. We then compare different variants of remove-restore technique with …