Physical Sciences and Mathematics Commons^™

Response To Turner 2017, Amy M. Schueller, Robert T. Leaf, Raymond M. Mroch Iii, Geneviève M. Nesslage

Faculty Publications

No abstract provided.

The Shape Of The Orbit In Flrw Spacetimes, David Garfinkle, Lawrence R. Mead, H.I. Ringermacher

Faculty Publications

The shape of the orbit of a free particle is examined in Friedmann-Lemaître-Robertson-Walker (FLRW) cosmologies. The spatial projection of the orbit is time-independent and has a simple geometric description. We relate this description to the expression in terms of standard FLRW coordinates.

Pva/Chitosan/Silver Nanoparticles Electrospun Nanocomposites: Molecular Relaxations Investigated By Modern Broadband Dielectric Spectroscopy, Mohammad K. Hassan, Ahmed Abukmail, Alaa J. Hassiba, Kenneth A. Mauritz, Ahmed A. Elzatahry

Faculty Publications

In this study, we used broadband dielectric spectroscopy to analyze polymer nanofibers of poly(vinyl alcohol)/chitosan/silver nanoparticles. We also studied the effect of incorporating silver nanoparticles in the polymeric mat, on the chain motion dynamics and their interactions with chitosan nanofibers, and we calculated the activation energies of the sub-T_g relaxation processes. Results revealed the existence of two sub-T_g relaxations, the first gets activated at very low temperature (−90 °C) and accounts for motions of the side groups within the repeating unit such as –NH₂, –OH, and –CH₂OH in chitosan and poly(vinyl alcohol). The second …

Information-Driven Inverse Approach To Disordered Solids: Applications To Amorphous Silicon, Dil K. Limbu, Raymond Atta-Fynn, David A. Drabold, Stephen R. Elliott, Parthapratim Biswas

Faculty Publications

© Physical Review Materials

Publisher's Version

A Statistical Analysis Of Steve, Bea Gallardo‐Lacourt, Y. Nishimura, E. Donovan, G. W. Gillies, W. E. Archer, Omar A. Nava, E. L. Spanswick

Faculty Publications

There has been an exciting recent development in auroral research associated with the discovery of a new subauroral phenomenon called STEVE (Strong Thermal Emission Velocity Enhancement). Although STEVE has been documented by amateur night sky watchers for decades, it is as yet an unidentified upper atmosphere phenomenon. Observed first by amateur auroral photographers, STEVE appears as a narrow luminous structure across the night sky over thousands of kilometers in the east‐west direction. In this paper, we present the first statistical analysis of the properties of 28 STEVE events identified using Time History of Events and Macroscale Interactions during Substorms (THEMIS) …

Optimal Policy For Sequential Stochastic Resource Allocation, Kalyanam Krishnamoorthy, Meir Pachter, David W. Casbeer

Faculty Publications

A gambler in possession of R chips/coins is allowed N(>R) pulls/trials at a slot machine. Upon pulling the arm, the slot machine realizes a random state i ɛ{1, ..., M} with probability p(i) and the corresponding positive monetary reward g(i) is presented to the gambler. The gambler can accept the reward by inserting a coin in the machine. However, the dilemma facing the gambler is whether to spend the coin or keep it in reserve hoping to pick up a greater reward in the future. We assume that the gambler has full knowledge of the reward distribution function. We …

Modification Of Asphalt Rubber With Nanoclay Towards Enhanced Storage Stability, Song-Yi Park, Minji Kang, Lynne Wilkens, Yurii Shvetsov, Brook Harmon, Nitin Shivappa, Michael Wirth, James R. Hébert, Christopher Haiman, Loïc Le Marchand, Carol Boushey

Faculty Publications

Asphalt rubber (AR), which is prepared by blending crumb rubber and bitumen, provides various advantages, including superior rutting resistance, lower road-tire noise and longer service life. However, contractors have expressed concerns regarding its poor storage stability, which in turn limits its wider application. This study aims to address the storage stability concern by incorporating nano-montmorillonite (nanoclay). Three types of nanoclay were dispersed into hot AR binder by high shear blending. The rheological properties of nanoclay-crumb rubber modifier (CRM)-modified bitumen were evaluated through Superpave performance grade (PG) tests and the storage stability was characterized by measuring the difference in softening points …

Estimation Of Atmospheric Turbulence Using Differential Motion Of Extended Features In Time-Lapse Imagery, Santasri Bose-Pillai, Jack E. Mccrae, Christopher A. Rice, Ryan A. Wood, Conner E. Murphy, Steven T. Fiorino

Faculty Publications

We address the design, development, and testing of a pointer/tracker as a probe beam for the purpose of making high-speed, aero-optical measurements of the flow over a scaled beam director turret. The tracker uses retro-reflection of the probe beam off of a Reflexite annulus surrounding the turret. The constraints of the design required a near-total-commercial off the shelf system that could be quickly installed and removed in a rented aircraft. Baseline measurements of environmental vibrations are used to predict pointing performance; mitigation of line-of-sight jitter on the probe beam is achieved through passive isolation and the design of relay optics. …

Metallo-Polyelectrolytes As A Class Of Ionic Macromolecules For Functional Materials, Tianyu Zhu, Ye Sha, Jing Yan, Parasmani Pageni, Md Anisur Rahman, Yi Yan, Chuanbing Tang

Faculty Publications

The fields of soft polymers and macromolecular sciences have enjoyed a unique combination of metals and organic frameworks in the name of metallopolymers or organometallic polymers. When metallopolymers carry charged groups, they form a class of metal-containing polyelectrolytes or metallo-polyelectrolytes. This review identifies the unique properties and functions of metallo-polyelectrolytes compared with conventional organo-polyelectrolytes, in the hope of shedding light on the formation of functional materials with intriguing applications and potential benefits. It concludes with a critical perspective on the challenges and hurdles for metallo-polyelectrolytes, especially experimental quantitative analysis and theoretical modeling of ionic binding.

Wide-Field Kinematics Of Globular Clusters In The Leo I Group (Corrigendum), G. Bergond, S. Zepf, Aaron Romanowsky, R. Sharples, K. Rhode

Faculty Publications

No abstract provided.

Equiangular Tight Frames That Contain Regular Simplices, Matthew C. Fickus, John Jasper, Emily J. King, Dustin G. Mixon

Faculty Publications

An equiangular tight frame (ETF) is a type of optimal packing of lines in Euclidean space. A regular simplex is a special type of ETF in which the number of vectors is one more than the dimension of the space they span. In this paper, we consider ETFs that contain a regular simplex, that is, have the property that a subset of its vectors forms a regular simplex. As we explain, such ETFs are characterized as those that achieve equality in a certain well-known bound from the theory of compressed sensing. We then consider the so-called binder of such an …

Unexpected Effects Of Inorganic Phosphate Glass On Crystallization And Thermo-Rheological Behavior Of Polyethylene Terephthalate, Kyoungtae Kim, Shahab Kashani Rahimi, Todd M. Alam, Eric G. Sorte, Joshua U. Otaigbe

Faculty Publications

The effects of ultra-low glass transition temperature (T_g) phosphate glass (Pglass) on the thermal, morphological, rheological, mechanical, and crystallization properties of hybrid Pglass/poly(eththylene terephthalate)(PET) were investigated. Nano- and micro-scale distribution of the Pglass in the PET polymer matrix was observed. The polydispersed Pglass in the PET matrix functioned as a nucleation agent, resulting in increasing crystallization temperature. The Pglass in the PET matrix decreased the T_g, indicating a plasticizing effect of the Pglass in the hybrids that was confirmed by the significantly decreased complex viscosity of the PET matrix. In addition, with increasing temperature, a non-terminal …

Search For The Lepton-Flavour Violating Decays B0→K∗0Μ ± E ∓, S. Sandilya, K. Trabelsi, A.J. Schwartz, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, V. Aulchenko, T. Aushev, R. Ayad, V. Babu, I. Badhrees, S. Bahinipati, A. M. Bakich, V. Bansal, P. Behera, C. Beleño, V. Bhardwaj, B. Bhuyan, Milind Purohit, Et. Al.

Faculty Publications

We have searched for the lepton-flavor-violating decay B⁰ → K^*0μ ^±e∓ using a data sample of 711 fb⁻¹ that contains 772 × 10⁶ B B̅ pairs. The data were collected near the ϒð4SÞresonance with the Belle detector at the KEKB asymmetric-energy eþe− collider. No signals were observed, and we set 90% confidence level upper limits on the branching fractions of B(B⁰ →K^*0μ⁺e⁻)<1.2×10⁻⁷, B(B⁰ → K^*0μ⁻e⁺) < 1.6 × 10⁻⁷, and, for both decays combined, B(B⁰ → K …

Equiangular Tight Frames From Group Divisible Designs, Matthew C. Fickus, John Jasper

Faculty Publications

An equiangular tight frame (ETF) is a type of optimal packing of lines in a real or complex Hilbert space. In the complex case, the existence of an ETF of a given size remains an open problem in many cases. In this paper, we observe that many of the known constructions of ETFs are of one of two types. We further provide a new method for combining a given ETF of one of these two types with an appropriate group divisible design (GDD) in order to produce a larger ETF of the same type. By applying this method to known …

A Maximum Entropy Method For Solving The Boundary Value Problem Of Second Order Ordinary Differential Equations, Congming Jin, Jiu Ding

Faculty Publications

We propose a new method to solve the boundary value problem for a class of second order linear ordinary differential equations, which has a non-negative solution. The method applies the maximum entropy principle to approximating the solution numerically. The theoretical analysis and numerical examples show that our method is convergent.

Data On Ion Composition And X-Ray Diffraction Patterns Of Biosolids From Wastewater Treatment Plants In Lufkin And Nacogdoches, Texas, Usa, Kefa Karimu Onchoke, Christopher M. Franclemont, Paul W. Weatherford

Faculty Publications

The data presented in this article is related to the research article entitled, “Structural Characterization and Evaluation of Municipal Wastewater Sludge (Biosolids) from two Rural Wastewater Treatment Plants in East Texas, USA”, Onchoke, KK, Franclemont, C.M., Spectrochim. Acta A, In press[1]. The XRD profiles and composition of biosolids from wastewater treatment plant is presented. This study describes the composition of XRD crystalline phase patterns of the wastewater sludge. After the removal of the Ka2 peaks the d-spacing and hkl values were determined. In addition, the ion chromatographic profile of the seven anions (NO₃^-, NO_{2 …}

Origins Of Ultradiffuse Galaxies In The Coma Cluster – Ii. Constraints From Their Stellar Populations, Anna Ferre-Mateu, Adebusola Alabi, Duncan Forbes, Aaron Romanowsky, Jean Brodie, Viraj Pandya, Ignacio Mart´In-Navarro, Sabine Bellstedt, Asher Wasserman, Maria Stone, Nobuhiro Okabe

Faculty Publications

In this second paper of the series we study, with new Keck/DEIMOS spectra, the stellar populations of seven spectroscopically confirmed ultradiffuse galaxies (UDGs) in the Coma cluster. We find intermediate to old ages (∼7 Gyr), low metallicities ([Z/H] ∼ −0.7 dex) and mostly supersolar abundance patterns ([Mg/Fe] ∼ 0.13 dex). These properties are similar to those of low-luminosity (dwarf) galaxies inhabiting the same area in the cluster and are mostly consistent with being the continuity of the stellar mass scaling relations of more massive galaxies. These UDGs’ star formation histories imply a relatively recent infall into the Coma cluster, consistent …

Chromodynamical Analysis Of Lenticular Galaxies Using Globular Clusters And Planetary Nebulae, Emilio Zanatta, Arianna Cortesi, Ana Chies-Santos, Duncan Forbes, Aaron Romanowsky, Adebusola Alabi, Lodovico Coccato, Claudia Mendes De Oliveira, Jean Brodie, Michael Merrifield

Faculty Publications

Recovering the origins of lenticular galaxies can shed light on the understanding of galaxy and compare them with the kinematics of planetary nebulae (PNe). The PNe and GC data come from the Planetary Nebulae Spectrograph and the SLUGGS Surveys. Through photometric spheroid-disc decomposition and PNe kinematics. we find the probability for a given GC to belong to either the spheroid or the disc of its host galaxy or be rejected from the model. We find that there is no correlation between the components that the GCs are likely to belong to and their colours. Particularly, for NGC 2768, we find …

Malware Analysis On Android Using Supervised Machine Learning Techniques, Md Shohel Rana, Andrew H. Sung

Faculty Publications

In recent years, a widespread research is conducted with the growth of malware resulted in the domain of malware analysis and detection in Android devices. Android, a mobile-based operating system currently having more than one billion active users with a high market impact that have inspired the expansion of malware by cyber criminals. Android implements a different architecture and security controls to solve the problems caused by malware, such as unique user ID (UID) for each application, system permissions, and its distribution platform Google Play. There are numerous ways to violate that fortification, and how the complexity of creating a …

Quinolines From The Cyclocondensation Of Isatoic Anhydride With Ethyl Acetoacetate: Preparation Of Ethyl 4-Hydroxy-2-Methylquinoline-3-Carboxylate And Derivatives, Nicholas Jentsch, Jared D. Hume, Emily B. Crull, Samer M. Beauti, Amy H. Pham, Julie A. Pigza, Jacques Kessl, Matthew G. Donahue

Faculty Publications

A convenient two-step synthesis of ethyl 4-hydroxy-2-methylquinoline-3-carboxylate derivatives has been developed starting from commercially available 2-aminobenzoic acids. In step 1, the anthranilic acids are smoothly converted to isatoic anhydrides using solid triphosgene in THF. In step 2, the anhydride electrophiles are reacted with the sodium enolate of ethyl acetoacetate, generated from sodium hydroxide, in warm N,N-dimethylacetamide resulting in the formation of substituted quinolines. A degradation–build-up strategy of the ethyl ester at the 3-position allowed for the construction of the α-hydroxyacetic acid residue required for the synthesis of key arylquinolines involved in an HIV integrase project.

An Extension Of The Method Of Brackets: Part 1, Ivan Gonzalez, Karen T. Kohl, Lin Jiu, Victor H. Moll

Faculty Publications

The method of brackets is an efficient method for the evaluation of a large class of definite integrals on the half-line. It is based on a small collection of rules, some of which are heuristic. The extension discussed here is based on the concepts of null and divergent series. These are formal representations of functions, whose coefficients an have meromorphic representations for n 2 C, but might vanish or blow up when n 2 N. These ideas are illustrated with the evaluation of a variety of entries from the classical table of integrals by Gradshteyn and Ryzhik.

Serpentinization: Connecting Geochemistry, Ancient Metabolism And Industrial Hydrogenation, Martina Preiner, Joana C. Xavier, Fliipa L. Sousa, Verena Zimorski, Anna Neubeck, Susan Q. Lang, H. Chris Greenwell, Karl Kleinermanns, Harun Tüysüz, Tom M. Mccollom, Nils G. Holm, William F. Martin

Faculty Publications

Rock–water–carbon interactions germane to serpentinization in hydrothermal vents have occurred for over 4 billion years, ever since there was liquid water on Earth. Serpentinization converts iron(II) containing minerals and water to magnetite (Fe₃O₄) plus H₂. The hydrogen can generate native metals such as awaruite (Ni₃Fe), a common serpentinization product. Awaruite catalyzes the synthesis of methane from H₂ and CO₂ under hydrothermal conditions. Native iron and nickel catalyze the synthesis of formate, methanol, acetate, and pyruvate—intermediates of the acetyl-CoA pathway, the most ancient pathway of CO₂ fixation. Carbon monoxide dehydrogenase …

Tourism Review Sentiment Classification Using A Bidirectional Recurrent Neural Network With An Attention Mechanism And Topic-Enriched Word Vectors, Qin Li, Shaobo Li, Jie Hu, Sen Zhang, Jianjun Hu

Faculty Publications

Sentiment analysis of online tourist reviews is playing an increasingly important role in tourism. Accurately capturing the attitudes of tourists regarding different aspects of the scenic sites or the overall polarity of their online reviews is key to tourism analysis and application. However, the performances of current document sentiment analysis methods are not satisfactory as they either neglect the topics of the document or do not consider that not all words contribute equally to the meaning of the text. In this work, we propose a bidirectional gated recurrent unit neural network model (BiGRULA) for sentiment analysis by combining a topic …

Guidelines And Considerations For Designing Field Experiments Simulating Precipitation Extremes In Forest Ecosystems, Heidi Asbjornsen, John L. Campbell, Katie A. Jennings, Matthew A. Vadeboncoeur, Cameron Mcintire, Pamela H. Templer, Richard P. Phillips, Taryn L. Bauerle, Michael C. Dietze, Serita D. Frey, Peter M. Groffman, Rosella Guerrieri, Paul J. Hanson, Eric P. Kelsey, Alan K. Knapp, Nathan G. Mcdowell, Patrick Meir, Kimberly A. Novick, Scott V. Ollinger, Will T. Pockman, Paul G. Schaberg, Stan D. Wullschleger, Melinda D. Smith, Lindsey E. Rustad

Faculty Publications

Precipitation regimes are changing in response to climate change, yet understanding of how forest ecosystems respond to extreme droughts and pluvials remains incomplete. As future precipitation extremes will likely fall outside the range of historical variability, precipitation manipulation experiments (PMEs) are critical to advancing knowledge about potential ecosystem responses. However, few PMEs have been conducted in forests compared to short-statured ecosystems, and forest PMEs have unique design requirements and constraints. Moreover, past forest PMEs have lacked coordination, limiting cross-site comparisons. Here, we review and synthesize approaches, challenges, and opportunities for conducting PMEs in forests, with the goal of guiding design …

Left Ventricular Mechanical Dyssynchrony For Cad Diagnosis: Does It Have Incremental Clinical Values?, Zhixin Jiang, Weihua Zhou

Faculty Publications

No abstract provided.

Cover Crops May Cause Winter Warming In Snow-Covered Regions, Danica L. Lombardozzi, Gordon B. Bonan

Faculty Publications

Cover crops, grown between cash crops when soil is fallow, are a management strategy that may help mitigate climate change. The biogeochemical effects of cover crops are well documented, as they provide numerous localized benefits to farmers. We test potential biogeophysical climate impacts of idealized cover crop scenarios by assuming that cover crops are planted offseason in all crop regions throughout North America. Our results suggest that planting cover crops increases wintertime temperature up to 3 °C in central North America by decreasing albedo in regions with variable snowpack. Cover crops with higher leaf area indices increase temperature more by …

End-To-End Convolutional Neural Network Model For Gear Fault Diagnosis Based On Sound Signals, Yong Yao, Honglei Wang, Shaobo Li, Zhongnhao Liu, Gui Gui, Yabo Dan, Jianjun Hu

Faculty Publications

Currently gear fault diagnosis is mainly based on vibration signals with a few studies on acoustic signal analysis. However, vibration signal acquisition is limited by its contact measuring while traditional acoustic-based gear fault diagnosis relies heavily on prior knowledge of signal processing techniques and diagnostic expertise. In this paper, a novel deep learning-based gear fault diagnosis method is proposed based on sound signal analysis. By establishing an end-to-end convolutional neural network (CNN), the time and frequency domain signals can be fed into the model as raw signals without feature engineering. Moreover, multi-channel information from different microphones can also be fused …

Enhancement Of Triplet-Sensitized Upconversion In Rigid Polymers Via Singlet Exciton Sink Approach, Steponas Raišys, Saulius Juršėnas, Yoan C. Simon, Christoph Weder, Karolis Kazlauskas

Faculty Publications

To increase the practical usefulness of solid-state sensitized upconversion (UC) materials as components of solar energy harvesting systems, it is important to identify and suppress loss mechanisms, and increase the UC quantum yield (Φ_UC). Here we focus on a benchmark UC system consisting of the emitter 9,10-diphenylanthracene (DPA) and the sensitizer platinum octaethylporphyrin (PtOEP) in a rigid poly(methyl methacrylate) (PMMA) matrix, and show that one of the major losses originates from Förster resonant energy transfer (FRET) from DPA back to PtOEP. Even though DPA emission lies within the PtOEP transparency window, the quantitative assessment of singlet exciton diffusion …

Little Lasting Impact Of The Paleocene-Eocene Thermal Maximum On Shallow Marine Molluscan Faunas, Linda Ivany, Carlie Pietsch, John Handley, Rowan Lockwood, Warren Allmon, Jocelyn Sessa

Faculty Publications

Global warming, acidification, and oxygen stress at the Paleocene-Eocene Thermal Maximum (PETM) are associated with severe extinction in the deep sea and major biogeographic and ecologic changes in planktonic and terrestrial ecosystems, yet impacts on shallow marine macrofaunas are obscured by the incompleteness of shelf sections. We analyze mollusk assemblages bracketing (but not including) the PETM and find few notable lasting impacts on diversity, turnover, functional ecology, body size, or life history of important clades. Infaunal and chemosymbiotic taxa become more common, and body size and abundance drop in one clade, consistent with hypoxia-driven selection, but within-clade changes are not …

Reliable Delay Based Algorithm To Boost Puf Security Against Modeling Attacks, Fathi Amsaad, Mohammaed Niamat, Amer Dawoud, Selcuk Kose

Faculty Publications

Silicon Physical Unclonable Functions (sPUFs) are one of the security primitives and state-of-the-art topics in hardware-oriented security and trust research. This paper presents an efficient and dynamic ring oscillator PUFs (d-ROPUFs) technique to improve sPUFs security against modeling attacks. In addition to enhancing the Entropy of weak ROPUF design, experimental results show that the proposed d-ROPUF technique allows the generation of larger and updated challenge-response pairs (CRP space) compared with simple ROPUF. Additionally, an innovative hardware-oriented security algorithm, namely, the Optimal Time Delay Algorithm (OTDA), is proposed. It is demonstrated that the OTDA algorithm significantly improves PUF reliability under varying …