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Wagging The Contact Line: Transverse And Longitudinal Waves, S. Saritha, Partho Neogi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Kinetics of wetting has been explored where the contact line not only sees a steady spreading but also has longitudinal or transverse oscillations imposed on it. The latter case is realized when spreading takes place over a rough surface. The effects of the imposed motion are small, which seem to be due to low spreading rates and small dynamic contact angles used in this study. However, a singularity is seen in viscous dissipation during the movement on the model rough surface, which is interpreted here as an instability that is similar to Haines' jumps and stick-slip phenomena, with possible entrainment …

Transition From Unilamellar To Bilameller Vesicles Induced By An Amphiphilic Biopolymer, Jae-Ho Lee, Vivek Argarwal, Arijit Bose, Gregory F. Payne, Srinivasa R. Raghavan

Chemical, Biomolecular, and Materials Engineering Faculty Publications

We report some unusual structural transitions upon the addition of an amphiphilic biopolymer to unilamellar surfactant vesicles. The polymer is a hydrophobically modified chitosan and it embeds its hydrophobes in vesicle bilayers. We study vesicle-polymer mixtures using small-angle neutron scattering (SANS) and cryotransmission electron microscopy (cryo-TEM). When low amounts of the polymer are added to unilamellar vesicles of ca. 120 nm diameter, the vesicle size decreases by about 50%. Upon further addition of polymer, lamellar peaks are observed in the SANS spectra at high scattering vectors. We show that these spectra correspond to a co-existence of unilamellar and bilamellar vesicles. …

Discover Magazine - Cyborg Bacteria, Ravi F. Saraf, Vikas Berry

Department of Chemical and Biomolecular Engineering: News Releases

In a society that has goldplated everything from hubcaps to teeth, it was perhaps inevitable that someone would find a way to add some bling to bacteria.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 22, Number 5, February 2006, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A six page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Dynamic Simulations Of Particle Suspensions Subjected To An External Electric-Field, Xianjin Jiang

Dissertations

A numerical method is performed to study the suspension of polarizable particles in nonconductive solvents subjected to external electric fields. Such particles experience both hydrodynamic and electrostatic interactions. The hydrodynamic force acting on the particles is determined using the Stokesian dynamics method under the assumption that the Reynolds number is much smaller than 1, while the electrostatic force is determined by differentiating the electrostatic energy of the suspension, which is computed from the induced particle dipoles. In addition, the multiple image method is used to compensate for the electrostatic force when two particles are close to each other. Because the …

The Effects Of Aging On Cardiac Mechanics, Samuel C. Lieber

Dissertations

It is well established that the aging heart exhibits left ventricular (LV) diastolic dysfunction and changes in mechanical properties, which have been attributed to alterations in the extracellular matrix (ECM). The investigators tested the hypothesis that the mechanical properties of cardiac myocytes significantly change with aging thereby contributing to the LV diastolic dysfunction. Cellular mechanical properties were determined by indenting cells with an atomic force microscope (AFM). The indentation results were interpreted by modeling the AFM probe as a blunted cone and determining an apparent elastic modulus (B) with classical infinitesimal strain theory (CIST). A commercially available finite element software …

Design And Resource Management Of Reconfigurable Multiprocessors For Data-Parallel Applications, Xiaofang Wang

Dissertations

FPGA (Field-Programmable Gate Array)-based custom reconfigurable computing machines have established themselves as low-cost and low-risk alternatives to ASIC (Application-Specific Integrated Circuit) implementations and general-purpose microprocessors in accelerating a wide range of computation-intensive applications. Most often they are Application Specific Programmable Circuiits (ASPCs), which are developer programmable instead of user programmable. The major disadvantages of ASPCs are minimal programmability, and significant time and energy overheads caused by required hardware reconfiguration when the problem size outnumbers the available reconfigurable resources; these problems are expected to become more serious with increases in the FPGA chip size. On the other hand, dominant high-performance computing …

Phase Transitions Of Poly (L-Lactic Acid) In Bulk And In Solution, Jing Zhang

Dissertations

Poly(L-lactic acid) (PLLA) has been subject to intensive research in recent years because of its biodegradability. Applications of PLLA, such as porous tissue engineering scaffolds and excipients for controlled release, have been developed in the biomedical and pharmaceutical fields. The crystal structures and morphologies of this semicrystalline polyester are the underlying factors that determine the mechanical and degradation properties of PLLA.

A fundamental understanding of the development of crystal structures and morphologies during the phase transitions of PLLA in bulk and in solution is pursued in this dissertation. Synchrotron wide- and small-angle x-ray scattering (WAXS and SAXS) are adopted as …

Online Clustering With Single-Pass Topology Based Fuzzy Clustering Algorithm, Abhishek Jaiantilal

Theses

Online clustering is of significant interest for real-time data analysis. Generic offline clustering methods such as K-Means, C-Means and others are computationally expensive. The computational burden of these methods increases non-linearly with the size of the data set. In addition these methods usually require a good amount of supervised knowledge yielding a non-unique solution. For real-time data analysis, there is an important tradeoff between accuracy and computational efficiency. An unsupervised one-pass clustering method that efficiently adapts to data distribution and evaluation is proposed. This method, Topology-Based Fuzzy Clustering (TFC), uses the topology of data to discover clusters. TFC uses the …

Impact Of Missed Beats On Heart Rate Variability Using Time-Frequency Analysis, Kilbrom T. Hailu

Theses

ECG recordings, especially during an exercise stress test, are exposed to artifacts. The source of artifacts can be due to technical problems, biological events and errors in the automatic detection. As a result missed beats, extra beats and ectopic beats can occur. In this study analysis of missed beats is performed using time-frequency analysis. Some of the patient's data had missed beats.

Fourier spectral analysis was first applied to the missed beats during the resting state. The impact of missed beats using Fourier spectral analysis is significant, especially, when the missed beats are in a row. The Fourier spectral analysis …

Doppler Ultrasound Technique Used To Determine The Blood Flow Viscosity In The Middle Cerebral Artery Of A Canine Animal Model, Raj P. Ganpath

Theses

The cerebral blood flow velocity in the middle cerebral artery of an canine animal model was measured using the Doppler Ultrasound technique. A transducer was designed with a 20 MHz piezoelectric crystal and used for the application. An in vitro calibration system was designed and machined for the purpose of testing and calibrating every transducer before using it in vivo. Preliminary tests included experiments on the in vitro system and measurement of blood flow velocity in the human wrist artery (metacarpal artery). The effect of using different transmission media (agarose and gelatin) was determined through the many in vitro and …

Demarcation Of Coding And Non-Coding Regions Of Dna Using Linear Transforms, Krithika Venkat

Theses

Deoxyribonucleic Acid (DNA) strand carries genetic information in the cell. A strand of DNA consists of nitrogenous molecules called nucleotides. Nucleotides triplets, or the codons, code for amino acids. There are two distinct regions in DNA, the gene and the intergenic DNA, or the junk DNA. Two regions can be distinguished in the gene- the exons, or the regions that code for amino acid, and the introns, or the regions that do not code for amino acid. The main aim of the thesis is to study signal processing techniques that help distinguish between the regions of the exons and the …

Remote Terrain Navigation For Unmanned Air Vehicles, Stephen R. Griffiths

Theses and Dissertations

There are many applications for which small unmanned aerial vehicles (SUAVs) are well suited, including surveillance, reconnaissance, search and rescue, convoy support, and short-range low-altitude perimeter patrol missions. As technologies for microcontrollers and small sensors have improved, so have the capabilities of SUAVs. These improvements in SUAV performance increase the possibility for hazardous missions through mountainous and urban terrain in the successful completion of many of these missions. The focus of this research was on remote terrain navigation and the issues faced when dealing with limited onboard processing and limited payload and power capabilities. Additional challenges associated with canyon and …

Catalytical Growth Of Carbon Nanotubes/Fibers From Nanocatalysts Prepared By Laser Pulverization Of Nickel Sulfate, J. Shi, Yongfeng Lu, K. F. Tan, Xinwei Wang

Department of Electrical and Computer Engineering: Faculty Publications

Dispersed nickel sulfate (NiSO₄) microclusters on Si substrates were fragmented by pulsed excimer laser irradiation to serve as catalysts for carbon nanotube/nanofiber (CNT/CNF) growth. At proper fluences, NiSO₄ clusters were pulverized into nanoparticles. The sizes of clusters/nanoparticles were found to be dependent on laser fluence and laser pulse number. By increasing the laser fluence from 100 to 300 mJ/cm², the size of disintegrated particles decreased drastically from several micrometers to several nanometers. It was found that laser-induced disintegration of as-dispersed NiSO₄ clusters was mainly due to physical fragmentation by transient thermal expansion/ contraction. Thermal …

Fuel-Nox Formation During Low-Grade Fuel Combustion In A Swirling-Flow Burner, Chunyang Wu

Theses and Dissertations

Insufficient knowledge of fireside behavior in the near-burner region during biomass combustion is one of major factors preventing widespread use of this renewable fuel in pulverized coal power plants. The current research is aimed to investigate the impact of biomass cofiring on NO formation in the near-burner region through interpretation of computational fluid dynamics (CFD) predictions and data collected from a series of biomass tests in a pilot-scale (0.2 MW), swirling flow burner. Two-dimensional gas species mole fraction data were collected with state-of-theart instruments from nine experiments, composing one herbaceous biomass (straw), one woody biomass (sawdust), a low sulfur sub-bituminous …

Coupling Between Lysozyme And Trehalose Dynamics: Microscopic Insights From Molecular-Dynamics Simulations, Taner E. Dirama, Joseph E. Curtis, Gustavo A. Carri, Alexei P. Sokolov

College of Polymer Science and Polymer Engineering

We have carried out molecular-dynamics simulations on fully flexible all-atom models of the protein lysozyme immersed in trehalose, an effective biopreservative, with the purpose of exploring the nature and extent of the dynamical coupling between them. Our study shows a strong coupling over a wide range of temperatures. We found that the onset of anharmonic behavior was dictated by changes in the dynamics and relaxation processes in the trehalose glass. The physical origin of protein-trehalose coupling was traced to the hydrogen bonds formed at the interface between the protein and the solvent. Moreover, protein-solvent hydrogen bonding was found to control …

Vegetative Treatment Systems For Management Of Open Lot Runoff: Review Of Literature, Richard K. Koelsch, Jeffrey C. Lorimer, Kyle R. Mankin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Runoff from open lot livestock systems (beef and dairy) defined as Concentrated Animal Feeding Operations (CAFO) must be controlled by systems designed and managed to prevent the release of manure-contaminated runoff for storms equal to or less than a 25-yr, 24-h design storm. This performance standard has been attained for open lot systems with some combination of clean water diversion, settling basins, runoff collection ponds, and irrigation systems (baseline system).

An alternative approach is to rely on overland flow and infiltration into cropland with perennial forage or grasses for treatment of open lot runoff. Such vegetative systems have been researched …

Simulated Performances Of A Heat Pump System For Energy And Water Conservation In Open And Confined Greenhouse Systems, Ilhami Yildiz, D. P. Stombaugh

BioResource and Agricultural Engineering

The purpose of this study was to determine and compare the performances of conventional and heat pump systems for energy and water conservation in open and confined greenhouse systems. Conventional gas furnaces and evaporative cooling, respectively, provided heating and cooling in the conventional system. In the heat pump systems, gas-fired heat pump units provided both heating and cooling. The greenhouse with heat pump units also had an option to be operated as a completely confined system, using one of the heat pump units as a dehumidifier. Average energy consumption in winter was 56.9, 23.5, and 11.3 MJ/day.m² in the conventional, …

Biomems Wireless Pressure Sensor, Daniel V. Pearce

Journal of the Microelectronic Engineering Conference

A design and manufacture of a wireless pressure sensor was proposed as a future tool for use in biological monitoring. This device is designed to acquire pressure changes through a change in capacitance. This is accomplished using a large circular parallel plate capacitor separated by a micron of air. The upper and lower plates are connected together via a large planar inductor on the opposite end of the device. The inductor and capacitor in a parallel form a resonant circuit with resonant frequency equal to one over the square root of inductance times capacitance. The resonant frequency can be dependent …

Microscopic Reactive Diffusion Of Uranium In The Contaminated Sediments At Hanford, United States, Chongxuan Liu, John M. Zachara, Wassana Yantasee, Paul D. Majors, James Mckinley

United States Department of Energy: Publications

Microscopic and spectroscopic analyses of uranium-contaminated sediments from select locations at the U.S. Department of Energy (DOE) Hanford site have revealed that sorbed uranium (U) often exists as uranyl precipitates associated with intragrain fractures of granitic clasts. The release of U to contacting fluids appears to be controlled by intragrain ion diffusion coupled with the dissolution kinetics of the precipitates that exist in the form of Na-boltwoodite. Here we present a coupled microscopic reactive diffusion model for the contaminated sediment on the basis of experimental measurements of intragrain diffusivity in the granitic lithic fragments and the dissolution kinetics of synthetic …

Reducing Long-Term Remedial Costs By Transport Modeling Optimization, David Becker, Barbara Minsker, Robert Greenwald, Yan Zhang, Karla Harre, Kathleen Yager, Chunmiao Zheng, Richard Peralta

United States Navy: Publications

The Department of Defense (DoD) Environmental Security Technology Certification Program and the Environmental Protection Agency sponsored a project to evaluate the benefits and utility of contaminant transport simulation-optimization algorithms against traditional (trial and error) modeling approaches. Three pump-and-treat facilities operated by the DoD were selected for inclusion in the project. Three optimization formulations were developed for each facility and solved independently by three modeling teams (two using simulation-optimization algorithms and one applying trial-and-error methods). The results clearly indicate that simulation-optimization methods are able to search a wider range of well locations and flow rates and identify better solutions than current …

Basic Materials Research Programs At The U.S. Air Force Office Of Scientific Research, Herbert C. Carlson, K. C. Goretta

United States Air Force: Publications

The Air Force Office of Scientific Research (AFOSR) annually sponsors approximately 5000 research scientists at 1000 universities and laboratories, generating about 10,000 Ph.D. graduates per decade, all expected to publish their basic research findings in peer-reviewed journals. After a brief introduction of the nature of AFOSR’s support to basic research in the U.S. and international scientific communities, work it supports at the frontiers of materials science is highlighted. One focused research theme that drives our investment is the MEANS program. It begins with the end in mind; materials are designed with practicable manufacture as an explicit initial goal. AFOSR’s broad …

Ontological Implications Of The Levels Of Conceptual Interoperability Model, Andreas Tolk, Charles D. Turnitsa, Saikou Y. Diallo

Computational Modeling & Simulation Engineering Faculty Publications

The Levels of Conceptual Interoperability Model (LCIM) was developed to cope with the different layers of interoperation of modeling & simulation applications. It introduced technical, syntactic, semantic, pragmatic, dynamic, and conceptual layers of interoperation and showed how they are related to the ideas of integratability, interoperability, and composability. This paper will be presented in the invited session "Ontology Driven Interoperability for Agile Applications using Information Systems: Requirements and Applications for Agent Mediated Decision Support" at WMSCI 2006.

Modeling Correlation And Dependence Among Intervals, Scott Ferson, Vladik Kreinovich

Departmental Technical Reports (CS)

This note introduces the notion of dependence among intervals to account for observed or theoretical constraints on the relationships among uncertain inputs in mathematical calculations. We define dependence as any restriction on the possible pairings of values within respective intervals and define nondependence as the degenerate case of no restrictions (which we carefully distinguish from independence in probability theory). Traditional interval calculations assume nondependence, but alternative assumptions are possible, including several which might be practical in engineering settings that would lead to tighter enclosures on arithmetic functions of intervals. We give best possible formulas for addition of intervals under several …

On The Functional Form Of Convex Underestimators For Twice Continuously Differentiable Functions, Chirstodoulos A. Floudas, Vladik Kreinovich

Departmental Technical Reports (CS)

The optimal functional form of convex underestimators for general twice continuously differentiable functions is of major importance in deterministic global optimization. In this paper, we provide new theoretical results that address the classes of optimal functional forms for the convex underestimators. These are derived based on the properties of shift-invariance and sign-invariance.

Kinetic Characterization For Pretreatment Of Timber Varieties And Switchgrass Using Diluted Acid Hydrolysis, Shu Chiang Yat

Dissertations, Master's Theses and Master's Reports - Open

In recent years, growing attention has been devoted to the use of lignocellulosic biomass as a feedstock to produce renewable carbohydrates as a source of energy products, including liquid alternatives to fossil fuels. The benefits of developing woody biomass to ethanol technology are to increase the long-term national energy security, reduce fossil energy consumption, lower greenhouse gas emissions, use renewable rather than depletable resources, and create local jobs. Currently, research is driven by the need to reduce the cost of biomass-ethanol production. One of the preferred methods is to thermochemically pretreat the biomass material and subsequently, enzymatically hydrolyze the pretreated …

Optimal Beam Forming For Laser Beam Propagation Through Random Media, Baoyong Liu

Dissertations, Master's Theses and Master's Reports - Open

Focusing optical beams on a target through random propagation media is very important in many applications such as free space optical communica- tions and laser weapons. Random media effects such as beam spread and scintillation can degrade the optical system's performance severely. Compensation schemes are needed in these applications to overcome these random media effcts. In this research, we investigated the optimal beams for two different optimization criteria: one is to maximize the concentrated received intensity and the other is to minimize the scintillation index at the target plane. In the study of the optimal beam to maximize the weighted …

Water Conservation And Wastewater Treatment, Samuel A. Vigil

Civil and Environmental Engineering

No abstract provided.

Effects, Transfer, And Fate Of Rdx From Aged Soil In Plants And Worms, E.P.H. Best, K.N. Geter, H.E. Tatem, B.K. Lane

United States Army: Publications

The objectives of this study were to provide data that can be used to predict exposure-based effects of RDX in aged soil on multiple endpoint organisms representing two trophic levels. These data can be used for defining criteria or reference values for environmental management and conducting specific risk assessment. Dose–response experiments formed the basis for the evaluation of toxic effects and transfer of contaminants from soil into two trophic levels. Long-term exposure tests were conducted to evaluate chronic, sublethal, toxicity and transfer of aged soil-based explosives, with RDX as main contaminant. In these tests, plants were exposed for 55 days …

Osteon Interfacial Strength And Histomorphometry Of Equine Cortical Bone, Robert F. Bigley, Lanny V. Griffin, Lisa Christensen, Ryan Vandenbosch

Biomedical Engineering

The interfacial strength of secondary osteons from the diaphysis of the Thoroughbred equine third metacarpal was evaluated using the fiber pushout test. The pushout was performed on 300–500 mm sections of 4x4x15mm bone blocks machined from four anatomic regions of the cortex. Pushout strength was evaluated from proximal to distal location within the diaphysis on four osteon types classified under polarized light on adjacent histologic sections from each block. The shear strength of the interfaces were estimated from shear lag theory. Differences were found in the interfacial strength of osteons based on appearance under polarized light with bright field having …