Physical Sciences and Mathematics Commons^™

Split-Step Approach To Electromagnetic Propagation Through Atmospheric Turbulence Using The Modified Von Karman Spectrum And Planar Apertures, Monish Ranjan Chatterjee, Fathi H.A. Mohamed

Electrical and Computer Engineering Faculty Publications

The impact of atmospheric phase turbulence on Gaussian beam propagation along propagation paths of varying lengths is examined using multiple random phase screens. The work is motivated by research involving generation and encryption of acousto-optic chaos, and the interest in examining propagation of such chaotic waves through atmospheric turbulence. A phase screen technique is used to simulate perturbations to the refractive index of the medium through the propagation path. A power spectral density based on the modified von Karman spectrum model for turbulence is used to describe the random phase behavior of the medium.

In recent work, results for the …

Improved Performance Of Analog And Digital Acousto-Optic Modulation With Feedback Under Profiled Beam Propagation For Secure Communication Using Chaos, Fares S. Almehmadi, Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

Using intensity feedback, the closed-loop behavior of an acousto-optic hybrid device under profiled beam propagation has been recently shown to exhibit wider chaotic bands potentially leading to an increase in both the dynamic range and sensitivity to key parameters that characterize the encryption. In this work, a detailed examination is carried out vis-à-vis the robustness of the encryption/decryption process relative to parameter mismatch for both analog and pulse code modulation signals, and bit error rate (BER) curves are used to examine the impact of additive white noise.

The simulations with profiled input beams are shown to produce a stronger encryption …

Review: The Wilderness Writings Of Howard Zahniser, Jillian M. Slater

Marian Library Faculty Publications

No abstract provided.

Discovery Of Thienoquinolone Derivatives As Selective And Atp Non-Competitive Cdk5/P25 Inhibitors By Structure-Based Virtual Screening, Arindam Chatterjee, Stephen J. Cutler, Robert J. Doerksen, Ikhlas A. Khan, John S. Williamson

Office for Research Publications and Presentations

Calpain mediated cleavage of CDK5 natural precursor p35 causes a stable complex formation of CDK5/p25, which leads to hyperphosphorylation of tau. Thus inhibition of this complex is a viable target for numerous acute and chronic neurodegenerative diseases involving tau protein, including Alzheimer’s disease. Since CDK5 has the highest sequence homology with its mitotic counterpart CDK2, our primary goal was to design selective CDK5/p25 inhibitors targeting neurodegeneration. A novel structure-based virtual screening protocol comprised of e-pharmacophore models and virtual screening workflow was used to identify nine compounds from a commercial database containing 2.84 million compounds. An ATP non-competitive and selective thieno[3,2- …

Sustainability Research Through The Lens Of Environmental Ethics, Daniel Clifford Fouke, Sukh Sidhu, Robert J. Brecha

Physics Faculty Publications

Two core courses in the curriculum of the University of Dayton’s Sustainability, Energy, and the Environment minor, Sustainability Research I and II, were developed out of the frustration one author, Daniel Fouke, experienced while teaching a traditional course on environmental ethics for the Department of Philosophy. The often-overwhelming nature of environmental problems tended to demoralize both the instructor and the students. Seeking a way to integrate ethical analysis of complex problems with the search for solutions, two courses were proposed that would be team-taught by a philosopher and a scientist or an engineer.

Development of the courses was initially funded …

2014 (Fall), University Of Dayton. Department Of Mathematics

Colloquia

Abstracts of the talks given at the 2014 Fall Colloquium.

Capacity Planning With Financial And Operational Hedging In Low‐Cost Countries, Lijian Chen, Shanling Li, Letian Wang

MIS/OM/DS Faculty Publications

The authors of this paper outline a capacity planning problem in which a risk-averse firm reserves capacities with potential suppliers that are located in multiple low-cost countries. While demand is uncertain, the firm also faces multi-country foreign currency exposures. This study develops a mean-variance model that maximizes the firm’s optimal utility and derives optimal utility and optimal decisions in capacity and financial hedging size. The authors show that when demand and exchange rate risks are perfectly correlated, a risk- averse firm, by using financial hedging, will achieve the same optimal utility as a risk-neutral firm. In this paper as well, …

Seeing Human Weight From A Single Rgb-D Image, Tam Nguyen, Jiashi Feng, Shuicheng Yan

Computer Science Faculty Publications

Human weight estimation is useful in a variety of potential applications, e.g., targeted advertisement, entertainment scenarios and forensic science. However, estimating weight only from color cues is particularly challenging since these cues are quite sensitive to lighting and imaging conditions. In this article, we propose a novel weight estimator based on a single RGB-D image, which utilizes the visual color cues and depth information. Our main contributions are three-fold.

First, we construct the W8-RGBD dataset including RGB-D images of different people with ground truth weight.

Second, the novel sideview shape feature and the feature fusion model are proposed to facilitate …

Modeling Of Power Spectral Density Of Modified Von Karman Atmospheric Phase Turbulence And Acousto-Optic Chaos Using Scattered Intensity Profiles Over Discrete Time Intervals, Monish Ranjan Chatterjee, Fathi H.A. Mohamed

Electrical and Computer Engineering Faculty Publications

In recent research, propagation of plane electromagnetic (EM) waves through a turbulent medium with modified von Karman phase characteristics was modeled and numerically simulated using transverse planar apertures representing narrow phase turbulence along the propagation path.

The case for extended turbulence was also studied by repeating the planar phase screens multiple times over the propagation path and incorporating diffractive effects via a split-step algorithm. The goal of the research reported here is to examine two random phenomena: (a) atmospheric turbulence due to von Karman-type phase fluctuations, and (b) chaos generated in an acousto-optic (A-O) Bragg cell under hybrid feedback. The …

Realization Of Negative Index In Second-Order Dispersive Metamaterials Using Standard Dispersion Models For Electromagnetic Parameters, Tarig A. Algadey, Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

In recent work, electromagnetic propagation velocities for plane waves in dispersive metamaterials were calculated assuming frequency dispersion up to the second order. The three velocities were expressed in terms of dispersive coefficients under certain simplifying constraints. Frequency domains were found to exist around resonances where group and phase velocities are in opposition, implying possible negative index behavior.

In this paper, we incorporate in the derived equations physical models (including Debye, Lorentz and Condon) for material dispersion in permittivity, permeability and chirality in order to further examine the consequences of second-order dispersion leading to negative index for practical cases, and also …

Information Encryption, Transmission, And Retrieval Via Chaotic Modulation In A Hybrid Acousto-Optic Bragg Cell Under Profiled Beam Illumination, Monish Ranjan Chatterjee, Fares S. Almehmadi

Electrical and Computer Engineering Faculty Publications

In recent work, the propagation of a profiled optical beam through an open-loop acousto-optic Bragg cell was examined using a transfer function formalism. The device was also studied under closed-loop via intensity feedback, and shown to exhibit more extended chaotic band responses, thereby potentially increasing the dynamic range and parameter sensitivities of any applied signal and the device operation respectively.

In this paper, simple low- to mid-RF signals (periodic waveforms and low BW audio) are transmitted through the closed-loop system and the resulting encryption and recovery at the receiver are examined especially from the perspective of overall robustness of the …

Numerical Investigation Of The Nonlinear Dynamics Of A Hybrid Acousto-Optic Bragg Cell With A Variable Feedback Gain, Monish Ranjan Chatterjee, Hao Zhou

Electrical and Computer Engineering Faculty Publications

Since around 1979, the operation of an acousto-optic Bragg cell under positive first-order feedback via amplification and delay in the loop has been studied extensively by several groups [1-3]. In recent work, the analysis of the nonlinear dynamics (NLD) of the system was extended to include bistable maps and Lyapunov exponents, and application of the chaos for signal encryption and decryption for uniform plane waves. The present work originated with the problem of a variable photodetector aperture opening relative to the first-order light. This potentially complex problem is simplified by assuming instead a variable feedback gain ( β ~ (t)), …

Heat Release Of Polyurethanes Containing Potential Flame Retardants Based On Boron And Phosphorus Chemistries, Vladimir Benin, Bastien Gardelle, Alexander Morgan

Chemistry Faculty Publications

Using a polyurethane of methylene diphenyl isocyanate and 1,3-propane diol, several new non-halogenated aromatic boron and phosphorus flame retardants were evaluated for heat release reduction potential using the pyrolysis combustion flow calorimeter (PCFC). The polyurethanes were prepared in the presence of the potential flame retardants via solvent mixing and copolymerization methods, and were then analyzed via spectroscopic methods to determine if the flame retardant was still present in the final product. PCFC testing on the resulting products showed that the flame retardant molecule can have different effects on heat release depending upon how it is mixed into the polyurethane. Some …

Nonlocal And Quantum-Tunneling Contributions To Harmonic Generation In Nanostructures: Electron-Cloud-Screening Effects, Michael Scalora, Maria Antonietta Vincenti, Domenico De Ceglia, Joseph W. Haus

Electrical and Computer Engineering Faculty Publications

Our theoretical examination of second- and third-harmonic generation from metal-based nanostructures predicts that nonlocal and quantum-tunneling phenomena can significantly exceed expectations based solely on local, classical electromagnetism. Mindful that the diameter of typical transition-metal atoms is approximately 3 Å, we adopt a theoretical model that treats nanometer-size features and/or subnanometer-size gaps or spacers by taking into account (i) the limits imposed by atomic size to fulfill the requirements of continuum electrodynamics, (ii) spillage of the nearly free electron cloud into the surrounding vacuum, and (iii) the increased probability of quantum tunneling as objects are placed in close proximity.

Our approach …

2014 (Summer), University Of Dayton. Department Of Mathematics

Colloquia

Abstracts of the talks given at the 2014 Colloquium.

Structure Preserving Large Imagery Reconstruction, Ju Shen, Jianjun Yang, Sami Taha Abu Sneineh, Bryson Payne, Markus Hitz

Computer Science Faculty Publications

With the explosive growth of web-based cameras and mobile devices, billions of photographs are uploaded to the internet. We can trivially collect a huge number of photo streams for various goals, such as image clustering, 3D scene reconstruction, and other big data applications. However, such tasks are not easy due to the fact the retrieved photos can have large variations in their view perspectives, resolutions, lighting, noises, and distortions. Furthermore, with the occlusion of unexpected objects like people, vehicles, it is even more challenging to find feature correspondences and reconstruct realistic scenes. In this paper, we propose a structure-based image …

Determination Of Corrosion Inhibitor Lubricity Improver In Jet Fuel By Liquid Chromatography-Electrospray Ionization Mass Spectrometry, David W. Johnson, Milissa Flake, Ryan Adams

Chemistry Faculty Publications

Military jet fuel (JP-8) is very similar to commercial jet fuel (Jet A) except for the presence of three additives, fuel system icing inhibitor, corrosion inhibitor–lubricity improver (CI-LI), and antistatic additive, which are added to improve characteristics of JP-8. Of particular interest is the CI-LI additive; the most common active ingredient is a dimer of linoleic acid. This article focuses on quantification of the active ingredient in the CI-LI additive by liquid chromatography–mass spectrometry (LC–MS). This method will allow the determination of CI-LI content in military jet fuel samples.

A Small Molecule That Binds And Inhibits The Etv1 Transcription Factor Oncoprotein, Marius C. Pop, Nicolas Stransky, Colin W. Garvie, Jean-Philippe Theurillat, Emily C. Hartman, Timothy A. Lewis, Cheng Zhong, Elizabeth K. Culyba, Fallon Lin, Douglas S. Daniels, Raymond Pagliarini, Lucienne Ronco, Angela N. Koehler, Levi A. Garraway

Chemistry Faculty Publications

Members of the ETS transcription factor family have been implicated in several cancers, where they are often dysregulated by genomic derangement. ETS variant 1 (ETV1) is an ETS factor gene that undergoes chromosomal translocation in prostate cancers and Ewing's sarcomas, amplification in melanomas, and lineage dysregulation in gastrointestinal stromal tumors. Pharmacologic perturbation of ETV1 would be appealing in these cancers; however, oncogenic transcription factors are often deemed “undruggable” by conventional methods. Here, we used small-molecule microarray (SMM) screens to identify and characterize drug-like compounds that modulate the biological function of ETV1. We identified the 1,3,5-triazine small molecule BRD32048 as a …

Population Variation In Fossil Graptolites: A Quantitative Study Based On Single Species Assemblages, Elliott Matthias Mazur

Honors Theses

There are several different types of variation in populations of fossil organisms. These include intra-specific (population) variation, evolutionary variation (specimens on a slab accumulating over thousands of years), and preservational variation. An understanding of the extent and type of variation present in a population is fundamental to biological and paleontological studies. This study examines several populations of fossil graptolites from which population variation can be studied without the influence of the other types, and includes several types of morphometric analyses to examine population variation in several species of fossil graptolites. These analyses include isolating three dimensionally preserved specimens from limestone, …

Classifying The Functionality Of Primosome Protein A In Deinococcus Radiodurans, Jacob Boone

Honors Theses

Deinococcus radiodurans is an extremophile bacterium with the capacity to withstand tremendous DNA damage that causes disruption of replisome complex activity. The efficiency of origin-independent replisome reloading directly correlates to effectiveness of DNA damage coping strategies, and remains largely undefined in D. rad primosome components. Investigation of D. rad PriA as a helicase protein was conducted to determine if PriA could be classified as a fossilized helicase. This project tested the three functions of known helicases by comparing E. coli and D. rad PriA. DNA binding, DNA unwinding, and ATP hydrolysis assays were performed on both proteins separately and results …

Synthesis And Characterization Of Three Unique Mono-Metallic Lanthanide Complexes, Jasminder S. Grewal

Honors Theses

Three unique lanthanide complexes of formula Ln(tdh)3dpp (where Ln = Eu3+, Tb3+or Nd3+; tdh = 1,1,1- trifluoro-5,5-dimethyl-2,4-hexanedione and dpp = 2,3-Bis(2-pyridyl)pyrazine) were structurally characterized. X-ray quality crystals were grown through slow evaporation in a solution of concentrated ethyl acetate and hexanes. Each of the metals are eight coordinate, with 6 oxygen atoms from the tdh ligand and two nitrogen atoms from the dpp. Specifically, the nitrogen from 1-pyridyl group and the 1-pyrazine group coordinate to the lanthanide metal. Luminescent studies were performed on all three compounds. The Eu and Tb complexes were able to emit light in the visible region …

Investigating Bacterial Replication Restart: Can D.Rad Pria Load D.Rad Dnab Onto Dna Forks With A Leading Strand Gap?, Michael Ryan

Honors Theses

The bacteria Deinococcus radiodurans (D. rad) is able to survive multiple double stranded breaks to its DNA with no detriment to its health as its genome can be fully repaired in a matter of hours. During bacterial DNA replication, points of DNA damage can cause replication to cease, requiring an origin independent replisome loading pathway to resume the replication. This pathway is called replication restart , a highly conserved pathway in bacteria. In the E. coli replication restart pathway primosome proteins function by binding to the DNA fork and facilitating the loading of the DnaB helicase onto the replication fork. …

Synthesis And Purification Of A Nucleoside Platinum Complex That Promotes Dna Cross-Linking, Ryan Spear

Honors Theses

Cancer is a deadly and ever present disease in humans and its treatment has become a focus of many types of research. This project was designed to synthesize a platinum complex that will cross-link DNA and in turn cause cell death for rapidly dividing cells (usually cancer cells). The target compound strongly resembled the structure of a nucleic acid, thymidine. Further, nucleic acids are extremely important to cell life and cell membranes have transporters specific for them. Therefore, the purpose to exploring this new platinum complex was to create compound that a cell can easily transport inside its cell and …

The Promises And Challenges Of Innovating Through Big Data And Analytics In Healthcare, Donald E. Wynn, Renée M. E. Pratt

MIS/OM/DS Faculty Publications

In this article, we present the promises and challenges of big data and analytics (BD&A) in healthcare, informed by our observations of and interviews with healthcare providers in the US and European Union (EU). We then provide a set of recommendations for capitalizing on the extraordinary innovation opportunities available through big data.

Numerical Examination Of The Nonlinear Dynamics Of A Hybrid Acousto-Optic Bragg Cell With Positive Feedback Under Profiled Beam Propagation, Fares S. Almehmadi, Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

In standard weak interaction theory, acousto-optic Bragg analysis typically assumes that the incident light and sound beams are uniform plane waves. Acousto-optic Bragg diffraction with nonuniform profiled input beams is numerically examined under open loop via a transfer function formalism. Unexpected deviations in the first-order diffracted beam from the standard theory are observed for high �� values. These deviations are significant because the corresponding closed-loop system is sensitive to input amplitudes and initial conditions, and the overall impact on the dynamical behavior has not been studied previously in standard analyses. To explore the effect of such nonuniform output profiles on …

2014 (Spring), University Of Dayton. Department Of Mathematics

Colloquia

Abstracts of the talks given at the 2014 Spring Colloquium.

Synthesis And Characterization Of A Tetra-Ruthenated Naphthylbiliverdin, Ashley M. Berding

Honors Theses

A new naphtylbiliverdin compound has been synthesized which offers intense absorption with the photodynamic therapy window (600 nm – 850 nm). The compound has been characterized by proton NMR, high resolution electrospray mass spectrometry, elemental analysis, and UV/vis spectroscopy. Coordination of four ruthenium(II) polypyridyl complexes was accomplished by standard procedures. The new tetra-ruthenated naphthylbiliverdin was characterized by elemental analysis. Cyclic voltammetry measurements reveal that all four ruthenium moieties are coordinated to the pyridyl groups of the biliverdin compound. The intense metal to ligand charge transfer (MLCT) bands of the peripheral ruthenium groups overshadow the absorption due to the biliverdin compound; …

Exploring Data-Driven Electricity Feedback On Energy Conservation Behavior In The University Of Dayton Student Neighborhood, Daniel R. Esposito

Honors Theses

In general, homeowners do not have a concrete idea of how much energy their houses are using at any given moment. This energy “invisibility” is thought to be a barrier toward people adopting more sustainable behaviors. This study involves installing energy monitors in houses in the University of Dayton student neighborhood to analyze two important questions: whether the monitors teach students about the relationship between their activities and energy consumption, and whether the monitors influence students to adjust their household behaviors. Due to complications with and uncertainties in the data, quantitative conclusions could not be drawn. Fortunately, data collected from …

Design And Characterization Of Photoresponsive Supramolecular Aggregates, Julie A. Fitz

Honors Theses

Supramolecular chemistry concerns the manner in which molecular building blocks associate via non-covalent interactions and form aggregates. The particular building block in this research is a photoresponsive molecule 4,4’-azobenzene dicarboxylic acid (ADA), a molecule that isomerizes reversibly around an N-N double bond upon irradiation with different wavelengths of light. The large structural changes in the molecule that result from isomerization have the potential to modulate the properties of a supramolecular aggregate. ADA was studied under a variety of environmental conditions for the purpose of understanding aggregation behavior and geometries. A UV-Vis and Circular Dichroism (CD) spectroscopic study of ADA showed …

Multiframe Adaptive Wiener Filter Super-Resolution With Jpeg2000-Compressed Images, Barath Narayanan Narayanan, Russell C. Hardie, Eric J. Balster

Electrical and Computer Engineering Faculty Publications

Historically, Joint Photographic Experts Group 2000 (JPEG2000) image compression and multiframe super-resolution (SR) image processing techniques have evolved separately. In this paper, we propose and compare novel processing architectures for applying multiframe SR with JPEG2000 compression. We propose a modified adaptive Wiener filter (AWF) SR method and study its performance as JPEG2000 is incorporated in different ways. In particular, we perform compression prior to SR and compare this to compression after SR. We also compare both independent-frame compression and difference-frame compression approaches. We find that some of the SR artifacts that result from compression can be reduced by decreasing the …