Digital Commons Network^™

Sources And Cycling Of Carbonyl Sulfide In The Sargasso Sea, Gregory A. Cutter, Lynda S. Cutter, Katherine C. Filippino

OES Faculty Publications

The cycling of the radiatively important gas carbonyl sulfide (OCS) was studied in surface waters of the Sargasso Sea. In August 1999, surface OCS concentrations averaged 8.6 pmol L^-1, showed minor diel variations, and varied little with depth. An OCS precursor, total dissolved organic sulfur (DOS), was lowest at the surface (40 nmol L^-1) and increased with depth. The photoproduction rate of OCS from in situ incubations averaged 9.6 pmol L^-1 h^-1, whereas dark production was 7.0 pmol L^-1 h^-1. Apparent quantum yields were 10^-5-10^-7 from 313-436 …

Light Dependence Of Selenium Uptake By Phytoplankton And Implications For Predicting Selenium Incorporation Into Food Webs, Stephen B. Baines, Nicholas S. Fisher, Martina A. Doblin, Gregory A. Cutter, Lynda S. Cutter, Brian Cole

OES Faculty Publications

The potentially toxic element selenium is first concentrated from solution to a large but highly variable degree by algae and bacteria before being passed on to consumers. The large loads of abiotic and detrital suspended particles often present in rivers and estuaries may obscure spatial and temporal patterns in Se concentrations at the base of the food web. We used radiotracers to estimate uptake of both selenite (Se(IV)) and C by intact plankton communities at two sites in the Sacramento/San Joaquin River Delta. Our goals were to determine (1) whether C and Se(IV) uptake were coupled, (2) the role of …

Analytical Intercomparison Between Flow Injection-Chemiluminescence And Flow Injection-Spectrophotometry For The Determination Of Picomolar Concentrations Of Iron In Seawater, Andrew R. Bowie, Peter N. Sedwick, Paul J. Worsfold

OES Faculty Publications

A lab- and ship-based analytical intercomparison of two flow injection methods for the determination of iron in seawater was conducted, using three different sets of seawater samples collected from the Southern Ocean and South Atlantic. In one exercise, iron was determined in three different size-fractions (< 0.03 &μm, < 0.4 μm, and unfiltered) in an effort to better characterize the operational nature of each analytical technique with respect to filter size. Measured Fe concentrations were in the range 0.19 to 1.19 nM using flow injection with luminol chemiluminescence detection (FI-CL), and 0.07 to 1.54 nM using flow injection with catalytic spectrophotometric detection with N, N-dimethyl-p-phenylenediamine dihydrochloride (FI-DPD). The arithmetic mean for the FI-CL method was higher (by 0.09 nM) than the FI-DPD method for dissolved (< 0.4 μm) Fe, a difference that is comparable to the analytical blanks, which were as high as 0.13 nM ( CL) and 0.09 nM (DPD). There was generally good agreement between the FI-CL determinations for the < 0.03 μm size fraction and the FI-DPD determinations for the < 0.4 μm size fraction in freshly collected samples. Differences in total-dissolvable ( unfiltered) Fe concentrations determined by the two FI methods were more variable, reflecting the added complexity associated with the analysis of partially digested particulate material in these samples. Overall, however, the FI-CL determinations were significantly (P = 0.05) lower than the FI-DPD determinations for the unfiltered samples. Our results suggest that the observed, systematic inter-method differences reflect measurement of different physicochemical fractions of Fe present in seawater, such that colloidal and/or organic iron species are better determined by the FI-CL method than the FI-DPD method. This idea is supported by our observation that inter-method differences were largest for freshly collected acidified seawater, which suggests extended storage (>6 months) of acidified samples as a possible protocol for the determination of dissolved iron in seawater.

Optimization Of Blowing And Suction Control On Naca0012 Airfoil Using Genetic Algorithm With Diversity Control, Liang Huang

University of Kentucky Doctoral Dissertations

Active control of the flow over an airfoil is an area of heightened interest in the aerospace community. Previous research on flow control design processes heavily depended on trial and error and the designers knowledge and intuition. Such an approach cannot always meet the growing demands of higher design quality in less time. Successful application of computational fluid dynamics (CFD) to this kind of control problem critically depends on an efficient searching algorithm for design optimization. CFD in conjunction with Genetic Algorithms (GA) potentially offers an efficient and robust optimization method and is a promising solution for current flow control …

Electro-Optical Studies Of Charge-Density-Wave Materials, Ram C. Rai

University of Kentucky Doctoral Dissertations

A searched for narrow-band-noise (NBN) modulations of the infrared transmission in blue bronze has been performed. No modulations were observed, giving an upper limits for NBN changes in the absorption coefficient of )2000/(/3.0.andlt;.cmNBN. The implication of these results on proposed CDW properties and NBN mechanisms are discussed. An infrared microscope with a capability of doing both reflectance and transmission measurements has been integrated into the previous electro-transmission system with tunable diode lasers. Electro-optic experiments were done using the microscope for the studies of the CDW states of K0.3MoO3 (blue bronze) and orthorhombic TaS3. The electro-reflectance signal for blue bronze has …

Finite Element Simulation Of Indentation Of Porous Materials, Aditi Saran

University of Kentucky Master's Theses

Finite element simulation of indentation is presented in this thesis. A rigid cylindrical indenter of flat end is used in all the cases, in which the simulation focuses on the effect of a hole on the indentation behavior of materials including elastic and elasto-plastic materials. In the simulation, the material is assumed to be a half-space. The relations between load and displacement are determined as a function of the hole size. Also indentation under cyclic loading is simulated for an elastic-perfect plastic half space. The influence of factors causing fatigue deformation like amplitude, median load and frequency is addressed. The …

Regulation Of Concentrated Animal Feeding Operations: An Application Of Economic Theory To Firm Decision Making And Applications For Public Policy, Benjamin Gramig

University of Kentucky Master's Theses

The livestock industry in the United States has experienced significant concentration and vertical integration in recent years. This change has resulted in greater observed levels of pollution attributed to concentrated animal feeding operations (CAFO) and society has attempted to use regulation to remedy these problems. Despite regulation at the federal and local level no documented improvement in water quality has been observed to date. This thesis is concerned with the response of profit-maximizing economic agents to the form of environmental regulation adopted at the federal level. A theoretical model of firm profit is proposed and analyzed using comparative statics to …

Pokerface: Emotion Based Game-Play Techniques For Computer Poker Players, Lucas Cockerham

University of Kentucky Master's Theses

Numerous algorithms/methods exist for creating computer poker players. This thesis comparesand contrasts them. A set of poker agents for the system PokerFace are then introduced. A surveyof the problem of facial expression recognition is included in the hopes it may be used to build abetter computer poker player.

Bidirectional Lao* Algorithm (A Faster Approach To Solve Goal-Directed Mdps), Venkata Deepti Kiran Bhuma

University of Kentucky Master's Theses

Uncertainty is a feature of many AI applications. While there are polynomial-time algorithms for planning in stochastic systems, planning is still slow, in part because most algorithms plan for all eventualities. Algorithms such as LAO* are able to find good or optimal policies more quickly when the starting state of the system is known.

In this thesis we present an extension to LAO*, called BLAO*. BLAO* is an extension of the LAO* algorithm to a bidirectional search. We show that BLAO* finds optimal or ^_E-optimal solutions for goal-directed MDPs without necessarily evaluating the entire state space. BLAO* …

Methods Development And Application Of Two Dimensional Chromatography And Tandem Mass Spectrometry In Proteomics, Brett Romain Wenner

University of Kentucky Doctoral Dissertations

Although molybdenum blue solutions have been known for more than twocenturies, an understanding of their chemical nature is only beginning to emerge.This dissertation aimed at elucidating the structural nature of the polydisperse,nanoscopic components in the solution phases and the solid states of partiallyreduced polyoxomolybdate (Mo-POM). The study offered at least fourcontributions to the area: (1) a rational protocol for the molecular recognition ofMo-POM with de novo organic hosts. (2) demonstration of kinetic precipitation ofa dynamic mixture of polyoxomolybdates and application of the technique to thestudy of the dynamic mixture by TEM (3) characterization of the Mo-POMnanostructures by an unusual combination …

Pressurized Solvents In Whole-Cell Bioprocessing: Metabolic And Structural Perturbations, Geoffrey D. Bothun

University of Kentucky Doctoral Dissertations

Compressed and supercritical fluids, such as pressurized CO2, ethane, orpropane, provide a versatile and environmentally acceptable alternative to conventionalliquid organic solvents in bioprocessing applications – specifically in the areas ofproduct extraction, protein purification, microbial sterilization, and enzymatic and wholecellbiocatalysis. While their advantages have been well demonstrated, the effects ofcompressed and supercritical fluids on whole cells are largely unknown.Metabolic and structural perturbations of whole cells by compressed andsupercritical fluid solvents were examined. These perturbations exist as cell metabolismand membrane structure are influenced by pressure and the presence of a solventphase. Continuous cultures of Clostridium thermocellum (a model ethanol-producingthermophilic bacterium) were conducted …

Probabilistic Databases And Their Applications, Wenzhong Zhao

University of Kentucky Doctoral Dissertations

Probabilistic reasoning in databases has been an active area of research during the last twodecades. However, the previously proposed database approaches, including the probabilistic relationalapproach and the probabilistic object approach, are not good fits for storing and managingdiverse probability distributions along with their auxiliary information.The work in this dissertation extends significantly the initial semistructured probabilistic databaseframework proposed by Dekhtyar, Goldsmith and Hawkes in [20]. We extend the formal SemistructuredProbabilistic Object (SPO) data model of [20]. Accordingly, we also extend the SemistructuredProbabilistic Algebra (SP-algebra), the query algebra proposed for the SPO model.Based on the extended framework, we have designed and implemented …

Validation Of Detached Eddy Simulation Using Lestool For Homogeneous Turbulence, Sai Kumar Doddi

University of Kentucky Master's Theses

Detached Eddy Simulation (DES) is a hybrid turbulence model, a modification to the one-equation model proposed by Spalart and Allmaras (1997) [26]. It combines the advantages of both the RANS and LES models to predict any fluid flow. Presently, the focus is on using Homogeneous Turbulence to test the DES model. In an attempt to scrutinize this model, many cases are considered involving the variance of DES grid spacing parameter, CDES, the grid density, Reynolds number and cases with different initial conditions. Choosing Homogeneous Turbulence for our study alienates complications related to the geometry, boundary conditions and other flow characteristics …

Scale Model Experiments And Numerical Study On A Steel Teeming Process, Pavan Kumar Singh

University of Kentucky Master's Theses

During the teeming process of molten steel from a ladle, a bathtub-type vortex may be formed in the ladle. The vortex entrains undesired slag on the surface into the tundish, lowering the quality. The formation of such vortices has been studied using two different scale models. Since the kinematic viscosity of water is similar to that of molten steel, the molten steel was simulated by water in the experiments. The Particle Image Velocimetry (PIV) technique was used to measure water flow patterns. Results show that the initial tangential velocity of water is responsible for the vortex formation. The effects of …

A Development Of A Computer Aided Graphic User Interface Postprocessor For Rotor Bearing Systems, Pavan Kumar Arise

University of Kentucky Master's Theses

Rotor dynamic analysis, which requires extensive amount of data and rigorous analytical processing, has been eased by the advent of powerful and affordable digital computers. By incorporating the processor and a graphical interface post processor in a single set up, this program offers a consistent and efficient approach to rotor dynamic analysis. The graphic user interface presented in this program effectively addresses the inherent complexities of rotor dynamic analyses by linking the required computational algorithms together to constitute a comprehensive program by which input data and the results are exchanged, analyzed and graphically plotted with minimal effort by the user. …

Numerical Investigation Of Thermal Transport Mechanisms During Ultra-Fast Laser Heating Of Nano-Films Using 3-D Dual Phase Lag (Dpl) Model, Illayathambi Kunadian

University of Kentucky Master's Theses

Ultra-fast laser heating of nano-films is investigated using 3-D Dual Phase Lag heat transport equation with laser heating at different locations on the metal film. The energy absorption rate, which is used to model femtosecond laser heating, is modified to accommodate for three-dimensional laser heating. A numerical solution based on an explicit finite-difference method is employed to solve the DPL equation. The stability criterion for selecting a time step size is obtained using von Neumann eigenmode analysis, and grid function convergence tests are performed. DPL results are compared with classical diffusion and hyperbolic heat conduction models and significant differences among …

Finite Element Analysis And Reliability Study Of Multi-Piece Rims, Sandeep Chodavarapu

University of Kentucky Master's Theses

Multi-piece wheels or rims used on large vehicles such as trucks, tractors, trailers, buses and off-road machines have often been known for their dangerous properties because of the large number of catastrophic accidents involving them. The main causes for these accidents range from dislocation of the rim components in the assembly, mismatch of the components, manufacturing tolerances, corrosion of components to tires. A finite element analysis of a two-piece rim design similar to one manufactured by some of the prominent rim manufacturers in the USA is undertaken. A linear static deformation analysis is performed with the appropriate loading and boundary …

Uncorporated Professionals, John Romley, Eric L. Talley

Faculty Scholarship

Professional service providers who wish to organize as multi-person firms have historically been limited to the partnership form. Such organizational forms trade the benefit of risk diversification off against the costs of diluted incentives and liability exposure in choosing their optimal size. More recently, states have permitted limited-liability entities that combine the simplicity, flexibility and tax advantages of a partnership with the liability shield of a corporation. We develop a game theoretic model of professional-firm organization that integrates the provision of incentives in a multi-person firm with the choice of business form. We then test the model's predictions with a …

Development And Evaluation Of A Controller Area Network Based Autonomous Vehicle, Matthew John Darr

University of Kentucky Master's Theses

Through the work of researchers and the development of commercially availableproducts, automated guidance has become a viable option for agricultural producers.Some of the limitations of commercially available technologies are that they onlyautomate one function of the agricultural vehicle and that the systems are proprietary toa single machine model.The objective of this project was to evaluate a controller area network (CAN bus)as the basis of an automated guidance system. The prototype system utilized severalmicrocontroller-driven nodes to act as control points along a system wide CAN bus.Messages were transferred to the steering, transmission, and hitch control nodes from atask computer. The task …

Tolerance Allocation For Kinematic Systems, Mathieu Barraja

University of Kentucky Master's Theses

A method for allocating tolerances to exactly constrained assemblies is developed. The procedure is established as an optimization subject to constraints. The objective is to minimize the manufacturing cost of the assembly while respecting an acceptable level of performance. This method is particularly interesting for exactly constrained components that should be mass-produced. This thesis presents the different concepts used to develop the method. It describes exact constraint theory, manufacturing variations, optimization concepts, and the related mathematical tools. Then it explains how to relate these different topics in order to perform a tolerance allocation. The developed method is applied on two …

Experimental Study Of Active Separation Flow Control In A Low Pressure Turbine Blade Cascade Model, Mark Mcquilling

University of Kentucky Master's Theses

The flow field around a low pressure turbine (LPT) blade cascade model with and without flow control is examined using ejector nozzle (EN) and vortex generator jet (VGJ) geometries for separation control. The cascade model consists of 6 Pak-B Pratt andamp; Whitney low pressure turbine blades with Re = 30,000-50,000 at a free-stream turbulence intensity of 0.6%. The EN geometry consists of combined suction and blowing slots near the point of separation. The VGJs consist of a row of holes placed at an angle to the free-stream, and are tested at two locations of 69% and 10.5% of the suction …

Generation Of The Transient Electrical And Spontaneous Magnetic Fields By Solid State Combustion, Karen S. Martirosyan, J. R. Claycomb, J. H. Miller Jr., D. Luss

Physics & Astronomy Faculty Publications

Experiments revealed that transient electric field intensities up to 2.5 V/cm were generated during the initial period of combustion synthesis of the ferromagnetic products before the maximum temperature was reached. This occurred when the iron particles were partially oxidized and the reaction product was mainly magnetite sFe3O4d. The electromagnetic field caused spontaneous magnetization of the product in the postcombustion zone. Magnetic field values up to 4 µT formed after the sample temperature fell below the Curie temperature and the initial reactants were completely converted to the ferromagnetic phase PbFe12O19. Increasing the volume of the samples increases the absolute residual magnetic …

New Methods For Exafs Analysis In Structural Genomics, Grant Bunker, Nicholas Dimakis, Gocha Kelashvili

Physics & Astronomy Faculty Publications

Data analysis is one of the remaining bottlenecks in high-throughput EXAFS for structural genomics. Here some recent developments in methodology are described that offer the potential for rapid and automated XAS analysis of metalloproteins.

Xafs Debye-Waller Factors For Zn Metalloproteins, Nicholas Dimakis, Grant Bunker

Physics & Astronomy Faculty Publications

An accurate and practical method for the calculation and use of thermal x-ray absorption fine structure (XAFS) Debye-Waller factors (DWFs) in active sites of metalloproteins is presented. These factors are calculated on model clusters within the local density functional approximation with nonlocal corrections. The DWFs are mapped out and parametrized as a function of the first shell distance and an angle (where applicable), for all significant single and multiple scattering paths, as well as the sample temperature. This approach is applied to the biologically essential but spectroscopically silent Zn+2 active sites composed of histidines, cysteines, and carboxylate ligands in homogeneous …

Setting Upper Limits On The Strength Of Periodic Gravitational Waves From Psr J1939+2134 Using The First Science Data From The Geo 600 And Ligo Detectors, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Joseph D. Romano, Cristina V. Torres

Physics & Astronomy Faculty Publications

Data collected by the GEO 600 and LIGO interferometric gravitational wave detectors during their first observational science run were searched for continuous gravitational waves from the pulsar J1939+2134 at twice its rotation frequency. Two independent analysis methods were used and are demonstrated in this paper: a frequency domain method and a time domain method. Both achieve consistent null results, placing new upper limits on the strength of the pulsar’s gravitational wave emission. A model emission mechanism is used to interpret the limits as a constraint on the pulsar’s equatorial ellipticity.

Probing Molecular Free Energy Landscapes By Periodic Loading, Oliver Braun, Andreas Hanke, Udo Seifert

Physics & Astronomy Faculty Publications

Single molecule pulling experiments provide information about interactions in biomolecules that cannot be obtained by any other method. However, the reconstruction of the molecule’s free energy profile from the experimental data is still a challenge, in particular, for the unstable barrier regions. We propose a new method for obtaining the full profile by introducing a periodic ramp and using Jarzynski’s relation for obtaining equilibrium quantities from nonequilibrium data. Our simulated experiments show that this method delivers significant more accurate data than previous methods, under the constraint of equal experimental effort.

First Upper Limits From Ligo On Gravitational Wave Bursts, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Joseph D. Romano, Cristina V. Torres

Physics & Astronomy Faculty Publications

We report on a search for gravitational wave bursts using data from the first science run of the Laser Interferometer Gravitational Wave Observatory (LIGO) detectors. Our search focuses on bursts with durations ranging from 4 to 100 ms, and with significant power in the LIGO sensitivity band of 150 to 3000 Hz. We bound the rate for such detected bursts at less than 1.6 events per day at a 90% confidence level. This result is interpreted in terms of the detection efficiency for ad hoc waveforms (Gaussians and sine Gaussians) as a function of their root-sum-square strain hrss; typical sensitivities …

Analysis Of First Ligo Science Data For Stochastic Gravitational Waves, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present the analysis of between 50 and 100 h of coincident interferometric strain data used to search for and establish an upper limit on a stochastic background of gravitational radiation. These data come from the first LIGO science run, during which all three LIGO interferometers were operated over a 2-week period spanning August and September of 2002. The method of cross correlating the outputs of two interferometers is used for analysis. We describe in detail practical signal processing issues that arise when working with real data, and we establish an observational upper limit on a f−3 power spectrum of …

Analysis Of Ligo Data For Gravitational Waves From Binary Neutron Stars, B. P. Abbott, R. Abbott, Wm. R. Johnston, Joseph D. Romano, V. Schmidt

Physics & Astronomy Faculty Publications

We report on a search for gravitational waves from coalescing compact binary systems in the Milky Way and the Magellanic Clouds. The analysis uses data taken by two of the three LIGO interferometers during the first LIGO science run and illustrates a method of setting upper limits on inspiral event rates using interferometer data. The analysis pipeline is described with particular attention to data selection and coincidence between the two interferometers. We establish an observational upper limit of R

Nine Justices, Ten Years: A Statistical Retrospective, Robert J. Jackson Jr., Thiruvendran Vignarajah

Faculty Scholarship

The 2003 Term marked an unprecedented milestone for the Supreme Court: for the first time in history, nine Justices celebrated a full decade presiding together over the nation's highest court.' The continuity of the current Court is especially striking given that, on average, one new Justice has been appointed approximately every two years since the Court's expansion to nine members in 1837.2 Although the Harvard Law Review has prepared statistical retrospectives in the past,3 the last decade presents a rare opportunity to study the Court free from the disruptions of intervening appointments.

Presented here is a review of the 823 …