Physical Sciences and Mathematics Commons^™

Collaborative Research: Synergistic Merging Of Traditional Aeronomy With Targeted High-Frequency (Hf) Heating Diagnostics, Herbert C. Carlson

Funded Research Records

No abstract provided.

Boron Difluoride Adducts Of A Flexidentate Pyridine-Substituted Formazanate Ligand: Property Modulation Via Protonation And Coordination Chemistry, Stephanie M. Barbon, Jasmine V. Buddingh, Ryan R. Maar, Joe Gilroy

Chemistry Publications

The synthesis and characterization of a flexidentate pyridine-substituted formazanate ligand and its boron difluoride adducts, formed via two different coordination modes of the title ligand, are described. The first adduct adopted a structure that was typical of other boron difluoride adducts of triarylformazanate ligands and contained a free pyridine subsituent, while the second was formed via chelation of nitrogen atoms from the formazanate backbone and the pyridine substituent. Stepwise protonation of the pydridine-functionalized adduct, which is essentially non-emissive, resulted in a significant increase in the fluorescence quantum yield up to a maximum of 18%, prompting study of this adduct as …

Computer Science And Cultural History: A Dialogue, David B. Dennis, George K. Thiruvathukal

History: Faculty Publications and Other Works

No abstract provided.

Fabrication And Characterization Of Cuins₂ And Cuinse₂ Light-Absorbing Thin Films For Use In Solar Cells, Amy R. Tapley

Electronic Thesis and Dissertation Repository

Solar energy is free and globally abundant and harnessed cost-effectively, it has the potential to be the world’s main source of energy. CuInGa(S,Se)₂ solar cells have a very high efficiency of 20 %. However, gallium is a rare and expensive element. We have decided to work on its alternative CuInSe₂ (CISe) and CuInS₂ (CIS) by removing gallium or both gallium and selenium. The p-type CISe or CIS light-absorbing semiconducting layer is crucial for this type of solar cell. Preparation methods for CIS and CISe films were developed to reduce the costs and enhance the photoelectrochemical efficiency.

The …

Veress M., 2016. Covered Karsts, Reza Khoshraftar

International Journal of Speleology

No abstract provided.

The Firece Green Fire: Vol. 8 Issue 2, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

Identifying The Spatial Pattern And Importance Of Hydro-Geomorphic Drainage Impairments On Unpaved Roads In The Northeastern Usa, Beverley C. Wemple, Gordon E. Clark, Donald S. Ross, Donna M. Rizzo

College of Arts and Sciences Faculty Publications

Roads have been widely studied as sources of runoff and sediment and identified as pollutant production sources to receiving waters. Despite the wealth of research on logging roads in forested, upland settings, little work has been conducted to examine the role of extensive networks of rural, low-volume, unpaved roads on water quality degradation at the catchment scale. We studied a network of municipal unpaved roads in the northeastern US to identify the type and spatial extent of ‘hydro-geomorphic impairments’ to water quality. We mapped erosional and depositional features on roads to develop an estimate of pollutant production. We also mapped …

Factors Associated With Bat Mortality At Wind Energy Facilities In The United States, Maureen Thompson, Julie A. Beston, Matthew Etterson, Jay E. Diffendorfer, Scott R. Loss

United States Environmental Protection Agency: Publications

Hundreds of thousands of bats are killed annually by colliding with wind turbines in the U.S., yet little is known about factors causing variation in mortality across wind energy facilities. We conducted a quantitative synthesis of bat collision mortality with wind turbines by reviewing 218 North American studies representing 100 wind energy facilities. This data set, the largest compiled for bats to date, provides further evidence that collision mortality is greatest for migratory tree-roosting species (Hoary Bat [Lasiurus cinereus], Eastern Red Bat [Lasiurus borealis], Silver-haired Bat [Lasionycteris noctivagans]) and from July to October. Based …

Search For Low Mass Vector Resonances Decaying To Quark-Antiquark Pairs In Proton-Proton Collisions At √ S = 13 Tev, A. M. Sirunyan, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Tuhin Roy, Francisco Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

A search is reported for a narrow vector resonance decaying to quark-antiquark pairs in proton-proton collisions at ffiffiffi s p ¼ 13 TeV, collected with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.7 fb−1. The vector resonance is produced at large transverse momenta, with its decay products merged into a single jet. The resulting signature is a peak over background in the distribution of the invariant mass of the jet. The results are interpreted in the framework of a leptophobic vector resonance and no evidence is found for such particles in the …

Velocity-Dependent Inverse Cubic Force And Solar System Gravity Tests, Quentin G. Bailey, Daniel Havert

Publications

Higher mass dimension terms in an effective field theory framework for tests of spacetime symmetries are studied. Using a post-Newtonian expansion method, we derive the spacetime metric and the equations of motion for a binary system. This reveals an effective inverse cubic force correction to post-Newtonian general relativity that depends on the velocity of the bodies in the system. The results are studied in the context of laboratory and space-based tests including the effects on solar-system ephemeris, laser ranging observations, and gravimeter tests. This work reveals the coefficient combinations for mass dimension 5 operators controlling CPT violation for gravity that …

Climate Controls Over The Net Carbon Uptake Period And Amplitude Of Net Ecosystem Production In Temperate And Boreal Ecosystems, Zheng Fu, Paul C. Stoy, Yiqi Luo, Jiquan Chen, Jian Sun, Leonardo Montagnani, Georg Wohlfahrt, Abdullah F. Rahman, Serge Rambal, Christian Bernhofer

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Highlights

• The start of net C uptake was determined by spring temperature in DBF and EF.

• Summer precipitation determined NEPmax anomalies in DBF and GRA.

• Climate controls annual NEP variability by regulating CUP and NEPmax.

Abstract

The seasonal and interannual variability of the terrestrial carbon cycle is regulated by the interactions of climate and ecosystem function. However, the key factors and processes determining the interannual variability of net ecosystem productivity (NEP) in different biomes are far from clear. Here, we quantified yearly anomalies of seasonal and annual NEP, net carbon uptake period (CUP), and the maximum daily NEP (NEPmax) …

Elemental Mixing State Of Aerosol Particles Collected In Central Amazonia During Goamazon2014/15, Matthew Fraund, Don Q. Pham, Daniel Bonanno, Tristan H. Harder, Bingbing Wang, Joel Brito, Suzane S. De Sa, Samara Carbone, Swarup China, Paulo Artaxo, Scot T. Martin, Christopher Pöhlker, Meinrat O. Andreae, Alexander Laskin, Mary K. Gilles, Ryan C. Moffet

Department of Chemistry Student Articles

Two complementary techniques, Scanning Transmission X-ray Microscopy/Near Edge Fine Structure spectroscopy (STXM/NEXAFS) and Scanning Electron Microscopy/Energy Dispersive X-ray spectroscopy (SEM/EDX), have been quantitatively combined to characterize individual atmospheric particles. This pair of techniques was applied to particle samples at three sampling sites (ATTO, ZF2, and T3) in the Amazon basin as part of the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) field campaign during the dry season of 2014. The combined data was subjected to k-means clustering using mass fractions of the following elements: C, N, O, Na, Mg, P, S, Cl, K, Ca, Mn, Fe, Ni, and …

Design, Synthesis, And Biological Activity Of 5'-Phenyl-1,2,5,6-Tetrahydro-3,3'-Bipyridine Analogues As Potential Antagonists Of Nicotinic Acetylcholine Receptors, Yafei Jin, Xiaoqin Huang, Roger L. Papke, Emily M. Jutkiewicz, Hollis D Showalter, Chang-Guo Zhan

Pharmaceutical Sciences Faculty Publications

Starting from a known non-specific agonist (1) of nicotinic acetylcholine receptors (nAChRs), rationally guided structural-based design resulted in the discovery of a small series of 5′-phenyl-1,2,5,6-tetrahydro-3,3′-bipyridines (3a – 3e) incorporating a phenyl ring off the pyridine core of 1. The compounds were synthesized via successive Suzuki couplings on a suitably functionalized pyridine starting monomer 4 to append phenyl and pyridyl substituents off the 3- and 5-positions, respectively, and then make subsequent modifications on the flanking pyridyl ring to provide target compounds. Compound 3a is a novel antagonist which is highly selective for α3β4 nAChR (K_i = 123 nM) …

Designing An Ai That Cares

SIGNED: The Magazine of The Hong Kong Design Institute

The breakthrough that could change AI from being a plaything to being a playmate with which humans can have meaningful interations may be about to come from a seemingly unlikely source.

3½ Problems For Digital Assistants

SIGNED: The Magazine of The Hong Kong Design Institute

Digital home assistants promise to make life easier and happier. But a few problems stand in their way

Ai Centaurs

SIGNED: The Magazine of The Hong Kong Design Institute

As artificial intelligence outstrips human intelligence, AIs can now beat humans at any game. A pessimist might claim that this marks the end of the line for play. But a mythical beast has come to save playtime from the robots.

Initial Experience In Moving Key Academic Department Functions To Social Networking Sites, David Dennis, George K. Thiruvathukal, Konstantin Läufer

David B. Dennis

We discuss our initial experience with the transition from conventional technology to social networking sites and other cloud-backed sites for three core business functions of an academic computer science department at a mid-size private university: course management, research collaboration, and community engagement. We first discuss the social/cultural context that informs our technology choices, as well as the evolution of the technology choices themselves. Then, we identify the targeted department functions and their actors. Next, we describe the past and present technical architectures used to support these functions. We conclude with a discussion of our preliminary experience with this transition and …

History Of Computing, George K. Thiruvathukal, David B. Dennis

David B. Dennis

The social and organizational history of humanity is intricately entangled with the history of technology in general and the technology of information in particular. Advances in this area have often been closely involved in social and political transformations. While the contemporary period is often referred to by such names as the Computing and Information Age, this is the culmination of a series of historical transformations that have been centuries in the making. This course will provide a venue for students to learn about history through the evolution of number systems and arithmetic, calculating and computing machines, and advanced communication technology …

Moving Academic Department Functions To Social Networks And Clouds: Initial Experiences, George K. Thiruvathukal, Konstantin Läufer, David Dennis

David B. Dennis

The ability to move locally hosted services to cloud-based technologies is a key element in the scientific programming toolbox.

Architecture-Based Self-Adaptation For Moving Target Defense (Cmu-Isr-14-109), Bradley Schmerl, Javier Camara, Gabriel Moreno, David Garlan, Andrew O. Mellinger

Gabriel A. Moreno

The fundamental premise behind Moving Target Defense (MTD) is to create a dynamic and shifting system that is more difficult to attack than a static system because a constantly changing attack surface at least reduces the chance of an attacker finding and exploiting the weakness. However, MTD approaches are typically chosen without regard to other qualities of the system, such as performance or cost. This report explores the use of self-adaptive systems, in particular those based on the architecture of the running system. A systems software architecture can be used to trade off different quality dimensions of the system. In …

Prevention Of Renal Apob Retention Is Protective Against Diabetic Nephropathy: Role Of Tgf-Β Inhibition, Patricia G. Wilson, Joel C. Thompson, Meghan S. Yoder, Richard Charnigo, Lisa R. Tannock

Internal Medicine Faculty Publications

Animal studies demonstrate that hyperlipidemia and renal lipid accumulation contribute to the pathogenesis of diabetic nephropathy (DN). We previously demonstrated that renal lipoproteins colocalize with biglycan, a renal proteoglycan. The purpose of this study was to determine whether prevention of renal lipid (apoB) accumulation attenuates DN. Biglycan-deficient and biglycan wild-type Ldlr^−/− mice were made diabetic via streptozotocin and fed a high cholesterol diet. As biglycan deficiency is associated with elevated transforming growth factor-β (TGF-β), in some experiments mice were injected with either the TGF-β-neutralizing antibody, 1D11, or with 13C4, an irrelevant control antibody. Biglycan deficiency had no significant effect …

Molecular Tracers Of Star Formation Feedback In Nearby Galaxies, Mark Gorski

Physics & Astronomy ETDs

The energy and momentum injected into the ISM from stars has a drastic effect on the star formation history of a galaxy. This is called feedback. It is responsible for the inefficient collapse of the ISM into stars. The ``Survey of Water and Ammonia in Nearby Galaxies" (SWAN) is a survey of molecular line tracers in four nearby galaxies. By using molecular tracers of feedback, we provide insights into the star forming ecosystem of the galaxies NGC 253, IC 342, NGC 6946, and NGC 2146. These galaxies were chosen to span an order of magnitude in star formation rate and …

Laser Heating Of Graphite And Pulsed Laser Ablation Of Titanium And Aluminum, William A. Bauer

Theses and Dissertations

Tactical missions for laser weapons include a wide variety of targets, increasing the demands on the laser lethality community. New approaches to reducing the dimensionality of laser and materials interactions are necessary to increase predictive capability. Self-contained systematic experimental study was conducted on continuous wave and pulsed laser interaction with graphite, Al, and Ti. The spectroscopy and plume dynamics from the heating and ablation of these materials was examined to characterize laser weapons effects, develop graphite response for thermal protection systems, and provide optical diagnostics for materials processing. Furthermore, analysis of ablated plume velocity distributions shows application of conventional Maxwell-Boltzmann …

A Stochastic Model Of Plausibility In Live-Virtual-Constructive Environments, Jeremy R. Millar

Theses and Dissertations

Distributed live-virtual-constructive simulation promises a number of benefits for the test and evaluation community, including reduced costs, access to simulations of limited availability assets, the ability to conduct large-scale multi-service test events, and recapitalization of existing simulation investments. However, geographically distributed systems are subject to fundamental state consistency limitations that make assessing the data quality of live-virtual-constructive experiments difficult. This research presents a data quality model based on the notion of plausible interaction outcomes. This model explicitly accounts for the lack of absolute state consistency in distributed real-time systems and offers system designers a means of estimating data quality and …

Special Features Of The Air-To-Space Neutron Transport Problem, Whitman T. Dailey

Theses and Dissertations

Special features of the air-to-space neutron transport problem are identified, characterized, and quantified to provide information on features that should be included in Monte Carlo simulations to obtain accurate predictions. Currently available codes and tools for Monte Carlo neutron transport calculations do not provide an adequate (in accuracy nor precision nor efficiency) framework for practical transport calculations in the context of the air-to-space neutron transport problem. A new Fortran code, High Altitude Transport to Space for Neutrons (HATS-n), is developed and tested to perform high fidelity Monte Carlo neutron transport calculations for this class of problems. Special features of the …

Oblique Longwave Infrared Atmospheric Compensation, Daniel S. O'Keefe

Theses and Dissertations

This research introduces two novel oblique longwave infrared atmospheric compensation techniques for hyperspectral imagery, Oblique In-Scene Atmospheric Compensation (OISAC) and Radiance Detrending (RD). Current atmospheric compensation algorithms have been developed for nadir-viewing geometries which assume that every pixel in the scene is affected by the atmosphere in nearly the same manner. However, this assumption is violated in oblique imaging conditions where the transmission and path radiance vary continuously as a function of object-sensor range, negatively impacting current algorithms in their ability to compensate for the atmosphere. The techniques presented here leverage the changing viewing conditions to improve rather than hinder …

Three-Dimensional Imaging Of Cold Atoms In A Magneto-Optical Trap With A Light Field Microscope, Gordon E. Lott

Theses and Dissertations

Imaging of trapped atoms in three dimensions utilizing a light field microscope is demonstrated in this work. Such a system is of interest in the development of atom interferometer accelerometers in dynamic systems where strictly defined focal planes may be impractical. A light field microscope was constructed utilizing a Lytro® Development Kit micro-lens array and sensor. It was used to image fluorescing rubidium atoms in a magneto-optical trap. The three-dimensional (3D) volume of the atoms is reconstructed using a modeled point spread function (PSF), taking into consideration the low magnification (1.25) of the system which changed typical assumptions in the …

Analysis Of Ar(1s5) Metastable Populations In High Pressure Argon-Helium Gas Discharges, Daniel J. Emmons Ii

Theses and Dissertations

Simulations of an argon-helium plasma are performed for two high pressure discharge scenarios to find a uniform, large-volume plasma with Ar(1s5) metastable densities on the order of 10¹³ cm^-3 for use as the ground state in an optically pumped rare gas laser. An analysis of a pulsed direct current discharge is performed for a 7% argon in helium mixture at a pressure of 270 Torr using both zero and one-dimensional models. Kinetics of species relevant to the operation of an optically pumped rare gas laser are analyzed throughout the pulse duration to identify key reaction pathways. Simulations are …

A Tree Locality-Sensitive Hash For Secure Software Testing, Camdon J. Cady

Theses and Dissertations

Bugs in software that make it through testing can cost tens of millions of dollars each year, and in some cases can even result in the loss of human life. In order to eliminate bugs, developers may use symbolic execution to search through possible program states looking for anomalous states. Most of the computational effort to search through these states is spent solving path constraints in order to determine the feasibility of entering each state. State merging can make this search more efficient by combining program states, allowing multiple execution paths to be analyzed at the same time. However, a …

Biologically Inspired Network (Bionet) Authentication Using Logical And Pathological Rf-Dna Credential Pairs, Tyrone A.L. Lewis Sr.

Theses and Dissertations

The command and control (C2) of shared space resources are vulnerable to logical credential forgery and impersonation attacks among standardized and interoperable wireless radio frequency (RF) networks. Threats could come from trusted operators (insiders) or from external sources (outsiders). An attacker may gain unauthorized network access and illegally cross into C2 boundaries when conventional network authentication fails. This research proposes an integrated trust management system that uses both application-layer and physical-layer trust markers to authenticate users and their communication sources. In essence, the results from physical-layer RF-DNA fingerprinting techniques are used to improve application-level trust schemes based on command patterns, …