Digital Commons Network^™

Evaluation Of Numerical, Analytical, And Experimental Particle Deposition In Simple And Lung Geometries, Pamela M. Snyder

Theses

Particle deposition is utilized to determine exposure limits, design inhaled medications, and study pulmonary disorders that are a result of airborne pathogens. This information can be obtained from analytical equations, experimental studies, empirical relationships, and numerical analysis.

This research utilizes analytical equations, empirical relationships, and experimental data to investigate the accuracy of three Computational Fluid Dynamics (CFD) software packages; Fluent Discrete Phase Model (DPM), Fluent Fine Particle Model (FPM) and CFX. The sedimentation, molecular diffusion and impaction deposition mechanisms are investigated in a straight tube, bifurcating tube, and three generation lung geometry.

Sedimentation is evaluated in the straight tube for …

Security In Serverless Network Environments, Carl Holtje

Theses

As portable computing devices grow in popularity, so does the need for secure communications. Lacking tethers, these devices are ideal for forming small proximal groups in an ad-hoc fashion in environments where no server or permanent services are available. Members of these groups communicate over a broadcast or multicast network interconnect, and rely upon each other to form a cohesive group. While generally small in size and short in lifetime, security is a critical aspect of these groups that has received much academic attention in recent years. Much of the research focuses upon generating a common, group-wide private key suitable …

A Comparison Of Reputation-Based Trust Systems, John Folkerts

Theses

Recent literature contains many examples of reputation systems which are constructed in an ad hoc way or rely upon some heuristic which has been found to be useful. However, comparisons between these reputation systems has been impossible because there are no established methods of comparing performance. This paper introduces a simulation framework which can be used to perform comparison analysis between reputation models. Two reputation models, one from Abdul-Rahman and Hailes (ARH) [1], and one from Mui, Mohtashemi, and Halberstadt (MMH) [17] are implemented and compared with regard to accuracy, performance and resistance to deception. In order to improve performance …

Compact Realizations Of Embedded Filters In Organic Substrates, William Lambert

Theses

Making communication devices smaller, lighter, and cheaper has been the driving force behind the development of new technologies which have made the cellular phones and wireless networks we now take for granted possible. The frequent emphasis on miniaturization particularly has required the development of a variety of new approaches to creating communications circuits. One such technology that has attracted a great deal of attention in recent years is passives that are embedded into the package of communications integrated circuits. Using these devices reduces the amount of surface area required to implement a communications device, in addition to potentially improving performance …

Data Aggregation And Cross-Layer Design In Wsns, Carter May

Theses

Over the past few years, advances in electrical engineering have allowed electronic devices to shrink in both size and cost. It has become possible to incorporate environmental sensors into a single device with a microprocessor and memory to interpret the data and wireless transceivers to communicate the data. These "sensor nodes" have become small and cheap enough that they can be distributed in very large numbers into the area to be monitored and can be considered disposable. Once deployed, these sensor nodes should be able to self-organize themselves into a usable network. These "wireless sensor networks," or WSNs, differ from …

An Experimental Investigation Into The Effect Of Surfactants On Air-Water Two-Phase Flow In Minichannels, Nathan J. English

Theses

The complex interfacial phenomena involved in two-phase gas-liquid flow have defied mathematical simplification and modeling. However, the systems are used in heat exchangers, condensers, chemical processing plants, and nuclear reactor systems. The present work considers a 1 mm square minichannel and adiabatic flows corresponding to practical PEM fuel cell conditions. Pressure drop data is collected in experimentation covering mass fluxes of 4.0-33.6 kg/m2s, which correspond to superficial gas and liquid velocities of 3.4-10 m/s and 0.001-0.02 m/s respectively. The experiments are repeated with water of reduced surface tension, caused by the addition of surfactant, in order to quantify the surface …

Hardware And Software Multi-Precision Implementations Of Cryptographic Algorithms, Muhammad A. Janjua

Theses

The software implementations of cryptographic algorithms are considered to be very slow, when there are requirements of multi-precision arithmetic operations on very long integers. These arithmetic operations may include addition, subtraction, multiplication, division and exponentiation. Several research papers have been published providing different solutions to make these operations faster. Digital Signature Algorithm (DSA) is a cryptographic application that requires multi-precision arithmetic operations. These arithmetic operations are mostly based upon modular multiplication and exponentiation on integers of the size of 1024 bits. The use of such numbers is an essential part of providing high security against the cryptanalytic attacks on the …

Real-Time Control System Framework, Nishant Thakkar

Theses

Computer based controllers are being used increasingly in every aspect of modern life and have been integrated into everything from simple thermostats to the most complicated fighter jets. Multiple methodologies can be used within these controllers including differential equations, discrete difference equations, and fuzzy logic. Also, they can run on platforms ranging from scaled down versions of consumer operating systems to directly on embedded processors. What's missing is a low cost framework that links the variety of methodologies used in controllers and the variety of platforms that controllers can run on. My thesis is that it is possible to create …

Calabresi And The Intellectual History Of Law And Economics, Keith N. Hylton

Faculty Scholarship

This essay traces the vein of thought represented by Calabresi's "The Costs of Accidents", both backward in time to examine its sources, and forward to its impact on current scholarship. I focus on three broad topics: positive versus normative law and economics, positivist versus anti-positivist thinking in law, and the assumption of rationality in law and economics.

The Scopes Trope, Jay D. Wexler

Faculty Scholarship

In his book, Where Darwin Meets the Bible: Creationists and Evolutionists in America, journalist Larry Witham introduces the reader to the various characters involved in the ongoing controversy over evolution and creationism. His account is subtle and nuanced, and he demonstrates that the controversy is more complicated than many believe. Far from caricatures of godless scientists seeking to discard religion in thedustbin of history and reactionary religious fundamentalists decrying Darwinism as the downfall of mankind, Witham gives us the real stories of real people who dwell in shades far more gray than usually recognized. This book review builds upon Witham's …

Complexity Theory, Adaptation, And Administrative Law, Donald Thomas Hornstein

Faculty Publications

No abstract provided.

Regulation Of Glucose Metabolism In Dairy Cattle, Christie Cheatham Stanley

LSU Doctoral Dissertations

The experiments described herein are designed to elucidate many metabolic changes that occur to regulate the partitioning of nutrients between production and animal maintenance with particular regard to glucose metabolism and insulin sensitivity. The onset of milk production and parturition causes dramatic stress to the cow. The challenge of improving metabolism during this period is being addressed by nutritional management with the possibility of the addition of supplements. The use of Ca-propionate as a supplement did not affect glucose metabolism in transition cows. The data revealed that insulin sensitivity was low during the transition period, but the tissue responses to …

Quantitative Clay Mineralogy Of Several Louisiana Soils, Johan Forsman

LSU Master's Theses

A method was developed to simplify the approach to obtaining a better quantitative representation (QR) of complex clay mineral assemblages by XRD analysis. The method has eight steps: 1) preparation of samples with preferred orientation; 2) qualitative identification of phases; 3) peak decomposition to obtain precise locations of individual peaks contained within broad diffraction bands; 4) creation of a library of theoretical XRD patterns by modeling of one-dimensional XRD patterns; 5) selection of experimental library patterns; 6) employing the LINEST function found in common spreadsheet software to fit library patterns to experimental patterns; 7) evaluation of results to determine needed …

Tavis Mining Highway Stability Study - Methods Overview And Sensitivity Study, Matthew Jurgens

Undergraduate Theses and Senior Projects

This paper is a sensitivity study of highwall stability at Falkirk Mine. Since mining of the Tavis Creek will require maximizing the highwall height, this paper explores factors that influence the strength of the wall. The first part consists of a previous works review composed primarily of geology and geotechnical studies at the mine. As well, a basic site characterization is provided highlighting the general geologic and hydrologic features of the Riverdale field. A compilation of the fundamental numerical techniques and theory behind a geotechnical study of this nature is provided, as well as a model comparison, using limit equilibrium …

Stability In Dynamical Polysystems, George Cazacu

LSU Doctoral Dissertations

A dynamical polysystem consists of a family of continuous dynamical systems, all acting on a given metric space. The first chapter of the present thesis shows a generalization of control systems via dynamical polysystems and establishes the equivalence of the two notions under certain lipschitz condition on the function defining the dynamics. The remaining chapters are focused on a basic theory of dynamical polysystems. Some topological properties of limit sets are described in Chapter 2. Chapters 3 and 4 provide characterizations for various notions of strong stability. Chapter 5 makes use of the theory of closed relations to study Lyapunov …

Capillary And Microchip Gel Electrophoresis Using Multiplexed Fluorescence Detection With Both Time-Resolved And Spectral-Discrimination Capabilities: Applications In Dna Sequencing Using Near-Infrared Fluorescence, Li Zhu

LSU Doctoral Dissertations

Increasing the information content obtainable from a single assay and system miniaturization has continued to be important research areas in analytical chemistry. The research presented in this dissertation involves the development of a two-color, time-resolved fluorescence microscope for the acquisition of both steady-state and time-resolved data during capillary and microchip electrophoresis. The utility of this hybrid fluorescence detector has been demonstrated by applying it to DNA sequencing applications. Coupling color discrimination with time-resolved fluorescence offers increased multiplexing capabilities because the lifetime data adds another layer of information. An optical fiber-based fluorescence microscope was constructed, which utilized fluorescence in near-IR region, …

Error Estimates For Stabilized Approximation Methods For Semigroups, Sarah Campbell Mcallister

LSU Doctoral Dissertations

In this work we analyze error estimates for rational approximation methods, and their stabilizations, for strongly continuous semigroups. Chapter 1 consists of a brief survey of time discretization methods for semigroups. In Chapter 2, we demonstrate a new method for obtaining convergent approximations in the absence of stability for strongly continuous semigroups with arbitrary initial data. In Section 2.2, we state the stabilization result in more general form and show that this method can be used to improve known error estimates by a magnitude of up to one half for smooth initial data. In Section 2.3, we give concrete examples …

Computational Model For Elasto-Plastic And Damage Analysis Of Plates And Shells, Pawel Benedykt Woelke

LSU Doctoral Dissertations

Shells and plates are very important for various engineering applications. Analysis and design of these structures is therefore continuously of interest to the scientific and engineering community. Accurate and conservative assessments of the maximum load carried by the structure, as well as the equilibrium path in both elastic and inelastic range are of paramount importance. Elastic behaviour of shells has been very closely investigated, mostly by means of the finite element method. Inelastic analysis on the other hand, especially accounting for damage effects, has received much less attention from the researchers. A computational model for finite element, elasto-plastic and damage …

Complexifying The Poetic: Toward A Poiesis Of Curriculum, Donna Lynn Trueit

LSU Doctoral Dissertations

Inspired by philosopher Richard Rorty’s assertion that we need poetic imagination to move beyond modernity, this pragmatist inquiry seeks to understand the poetic, not as it is rationally defined, but rather as a historically situated discursive practice. In western cultures modernist discursive practices are characterized by rationalist reasoning. Traced to Aristotelian re- interpretations of mimesis (this is that), which structure modernist forms of representation, mimesis operates on a principle of equivalency between the specific and the universal, based on Euclidean, geometric reasoning. Likewise, mimesis underlies poetic representation as an imaginative expression of an objective reality, ideally, a form that moves …

Wavelet Sets With And Without Groups And Multiresolution Analysis, Mihaela Dobrescu

LSU Doctoral Dissertations

In this dissertation we study a special kind of wavelets, the so-called minimally supported frequency wavelets and the associated wavelet sets. Most of the examples of wavelet sets are for dilation sets which are groups. In this work we construct wavelet sets for which the dilation set, D, is of the form D=MN, where the product is direct, and so D is not necessarily group. In the second part of this dissertation we construct multiwavelets associated with MRA's and we generalize the rotations in the dilation sets to Coxeter groups.

Blind Multiridge Detection And Reconstruction Using Ultrasonic Signals, Rekha Katragadda

LSU Master's Theses

Time-frequency signal analysis has been widely applied in the modern radar, acoustic, sonar and ultrasonic signal processing techniques. Recently, the nondestructive testing (NDT) techniques via the ultrasonic instrumentation have shown the striking capability of the quality control for the material fabrication industry. In this thesis, we first provide a general mathematical model for the ultrasonic signals collected by pulse-echo sensors and then design a totally blind, novel, signal processing NDT technique relying on neither a priori signal information nor any manual effort. The signature signal can be blindly extracted by using the automatic optimal frame size selection for further modeling …

Active Security Mechanisms For Wireless Sensor Networks And Energy Optimization For Passive Security Routing, Lydia Ray

LSU Doctoral Dissertations

Wireless sensor networks consisting of numerous tiny low power autonomous sensor nodes provide us with the remarkable ability to remotely view and interact with the previously unobservable physical world. However, incorporating computation intensive security measures in sensor networks with limited resources is a challenging research issue. The objective of our thesis is to explore different security aspects of sensor networks and provide novel solutions for significant problems. We classify security mechanisms into two categories - active category and passive category. The problem of providing a secure communication infrastructure among randomly deployed sensor nodes requires active security measurements. Key pre-distribution is …

Fluvial Evolution Of The Garonne River, France: Integrating Field Data With Numerical Simulations, Robin Rene Lancaster

LSU Master's Theses

The Garonne River of southwestern France presents a unique opportunity to study the controls on long-term incision and terrace formation within a large-scale fluvial system. The Garonne heads in the Pyrenees, flows through the Aquitaine Basin, and discharges into Atlantic Ocean via the Gironde Estuary/Bay of Biscay. From field data, three terrace complexes were identified and traced for >251 km from the base of the Pyrenees to the onset of tidal influences. Each complex is separated from adjacent complexes by scarps >10 m and represent 10s to 100s kyrs during which time the river occupied a finite elevational range within …

Analysis Of Performance Of Single-Phase Reluctance Linear Motor, Subhadra Devi Ganti

LSU Master's Theses

The design and principle of operation, as well as the electromechanical phenomena of a single-phase linear reluctance motor are discussed. The motor with transverse magnetic flux consists of a primary part, which is moving and a secondary part which is stationary and does not have any windings. The motor can operate under AC or DC supply. When supplied from an AC source it must be equipped with a capacitor connected in series with the coil. In this case the motor operates on the basis of resonance in an RLC primary circuit. When supplied from a DC source it must be …

Modeling Of Chemical Fate And Transport In The Environment, Andre Marquette

LSU Master's Theses

The Environmental Engineering discipline remains on the forefront of discovery due to advancements in computer technology, advancements in experimental methods and an ever increasing public interest in mitigating the harmful effects of the chemical process industry. Experimental methods have a critical role in defining environmental processes and effects but are limited in their ability to predict future environmental conditions. Conceptual and mathematical models are needed in order to evaluate the effect of environmental conditions far into the future as well as to extend and apply the knowledge gained from experimentation. Models can be used to predict chemical exposure levels, design …

Modeling Destination Choice And Measuring The Transferability Of Hurricane Evacuation Patterns, Naveen Kumar Modali

LSU Master's Theses

In this study a gravity model was used to model destination choice during a hurricane evacuation. Hurricane Floyd data was used to calibrate and apply the gravity model. Two different models were generated for different destination types; home of friends/relative and hotels and motels are the two different destination types for which the models were generated. The performance of the gravity model was tested by comparing the observed and estimated OD matrices using the chi-squared test. The results have indicated that gravity model developed in this study can successfully reproduce the observed trip destinations during a hurricane evacuation The Floyd …

Modern Interpretation Of Euclid's Theory Of Ratio And Proportion, Mark Robert Stecher

LSU Master's Theses

Euclid’s Elements is the foundation for geometry. Book V of Euclid’s Elements, which is independent from the earlier books, focuses on multiples, ratios, and proportions. This paper presents a model of the conceptual content of Book V, but using carefully selected modern notation to represent Euclid’s ideas without changing them drastically. All of the propositions and proofs from Euclid have been restated using just enough modern language to make clear for a modern reader. We also present a modern theory that bears analogy, proposition by proposition, to Euclid’s theory, but uses rigorous modern methods of proof.

Quasicontinuous Derivatives And Viscosity Functions, Rodica Cazacu

LSU Doctoral Dissertations

In this work we demonstrate how the continuous domain theory can be applied to the theory of nonlinear optimization, particularly to the theory of viscosity solutions. We consider finding the viscosity solution for the Hamilton-Jacobi equation H(x, y) = g(x), with continuous hamiltonian, but with possibly discontinuous right-hand side. We begin by finding a new function space Q(X,L), the space of equivalence classes of quasicontinuous functions from a locally compact set X to a bicontinuous lattice L and we will define on Q(X,L) the qo-topology, which is a variant of classical order topology defined on complete lattices. On this …

Evaluation Of A Novel Method Of Predicting Estrogen Activity Of A Group Of Structurally Diverse Compounds, Daniel Consoer

LSU Master's Theses

The number of environmental chemicals found to have some level of endocrine activity has led to concern about the possible effects these compounds could have on human health and the health of other species, populations, and possibly whole ecosystems. The United States Environmental Protection Agency has been charged with testing a large number of these compounds, called endocrine-disrupting chemicals or hormonally active agents for hormonal activity. Limited testing resources have led to a call for alternate methods of screening, possibly for use in prioritizing this list to assist in efficient allocation of resources for further testing. This study describes a …

Analytical Separations Using Polymetric Surfactants, Mary Waithira Kamande

LSU Doctoral Dissertations

The goal of the research presented in this dissertation is to develop effective analytical methods for the separation of both achiral and chiral analytes using polymeric surfactants. Three analytical techniques are employed to accomplish this objective: open-tubular capillary electrochromatography (OT-CEC), open-tubular capillary electrochromatography coupled to mass spectrometry (OT-CEC/MS), and micellar affinity gradient focusing (MAGF). This research work presents novel application of polymeric surfactants that contributes to improved separations of difficult to separate analytes. The first part focuses on the application of an achiral polyelectrolyte multilayer (PEM) coating using OT-CEC. The PEM coating consisting of the cationic polymer poly (diallyldimethylammonium chloride), …