Digital Commons Network^™

Mechanisms Of Nanofilter Fouling And Treatment Alternatives For Surface Water Supplies, Charles Robert Reiss

Electronic Theses and Dissertations

This dissertation addresses the role of individual fouling mechanisms on productivity decline and solute mass transport in nanofiltration (NF) of surface waters. Fouling mechanisms as well as solute mass transport mechanisms and capabilities must be understood if NF of surface waters is to be successful. Nanofiltration of surface waters was evaluated at pilot-scale in conjunction with advanced pretreatment processes selected for minimization of nanofilter fouling, which constituted several integrated membrane systems (IMSs). Membrane fouling mechanisms of concern were precipitation, adsorption, particle plugging, and attached biological growth. Fouling was addressed by addition of acid and antiscalent for control of precipitation, addition …

An Interactive Distributed Simulation Framework With Application To Wireless Networks And Intrusion Detection, Oleg Kachirski

Electronic Theses and Dissertations

In this dissertation, we describe the portable, open-source distributed simulation framework (WINDS) targeting simulations of wireless network infrastructures that we have developed. We present the simulation framework which uses modular architecture and apply the framework to studies of mobility pattern effects, routing and intrusion detection mechanisms in simulations of large-scale wireless ad hoc, infrastructure, and totally mobile networks. The distributed simulations within the framework execute seamlessly and transparently to the user on a symmetric multiprocessor cluster computer or a network of computers with no modifications to the code or user objects. A visual graphical interface precisely depicts simulation object states …

Interconnection, Interface And Instrumentation For Micromachined Chemical Sensors, Naveenkumar Srinivasaiah Palsandram

Electronic Theses and Dissertations

In realizing a portable chemical analysis system, adequate partitioning of a reusable component and a disposable is required. For successful implementation of micromachined sensors in an instrument, reliable methods for interconnection and interface are in great demand between these two major parts. This thesis work investigates interconnection methods of micromachined chip devices, a hybrid fluidic interface system, and measurement circuitry for completing instrumentation. The interconnection method based on micromachining and injection molding techniques was developed and an interconnecting microfluidic package was designed, fabricated and tested. Alternatively, a plug-in type design for a large amount of sample flow was designed and …

Evaluation Of Proprietary Stormwater Treatment Devices In Field And Laboratory Conditions, Saheeda Marie Romah

Electronic Theses and Dissertations

Proper stormwater management acknowledges both water quantity and water quality. Historically, stormwater quantity and quality have been separately considered; runoff was routed as quickly as possible into the nearest body of water. Although this alleviates potential flooding concerns, water quality is often compromised. Common stormwater quality problems include gross pollutants, sediment, nutrients, and heavy metals. The chronic elevated presence of these pollutants is detrimental to the environment. As a result, the government has passed legislature to protect waterways. The passage of the National Pollution Discharge Elimination System (NPDES) permit requires that municipalities implement stormwater treatment techniques, known as Best Management …

Analyzing The Community Structure Of Web-Like Networks: Models And Algorithms, Aurel Cami

Electronic Theses and Dissertations

This dissertation investigates the community structure of web-like networks (i.e., large, random, real-life networks such as the World Wide Web and the Internet). Recently, it has been shown that many such networks have a locally dense and globally sparse structure with certain small, dense subgraphs occurring much more frequently than they do in the classical Erdös-Rényi random graphs. This peculiarity--which is commonly referred to as community structure--has been observed in seemingly unrelated networks such as the Web, email networks, citation networks, biological networks, etc. The pervasiveness of this phenomenon has led many researchers to believe that such cohesive groups of …

Instrumented Nanoindentation Studies Of Deformation In Shape Memory Alloys, Sudhir Rajagopalan

Electronic Theses and Dissertations

Near equi-atomic nickel titanium (NiTi) shape memory alloys (SMAs) are a class of materials characterized by their unique deformation behavior. In these alloys, deformation mechanisms such as mechanical twinning and stress induced phase transformation between a high symmetry phase (austenite) and a low symmetry phase (martensite) additionally occur and influence mechanical behavior and thus their functionality. Consequently, applications of SMAs usually call for precise phase transformation temperatures, which depend on the thermomechanical history and the composition of the alloy. Instrumented indentation, inherently a mechanical characterization technique for small sampling volumes, offers a cost effective means of empirically testing SMAs in …

Contributions To Automatic Particle Identification In Electron Micrographs: Algorithms, Implementation, And Applications, Vivek Singh

Electronic Theses and Dissertations

Three dimensional reconstruction of large macromolecules like viruses at resolutions below 8 Ã… - 10 Ã… requires a large set of projection images and the particle identification step becomes a bottleneck. Several automatic and semi-automatic particle detection algorithms have been developed along the years. We present a general technique designed to automatically identify the projection images of particles. The method utilizes Markov random field modelling of the projected images and involves a preprocessing of electron micrographs followed by image segmentation and post processing for boxing of the particle projections. Due to the typically extensive computational requirements for extracting hundreds of …

Vibration Analysis Of Carbon Nanotube Using Continuum Model And Finite Element Model, Hari Subramaniam

Electronic Theses and Dissertations

The main objective of the thesis is to propose the methods of determining vibration behavior of carbon nanotubes (CNTs) using continuum models and finite element models. Secondary objective is to find the effect of van der Waals force on vibration of multiwalled carbon nanotubes . The study of vibration behavior of CNTs is important because of their potential engineering applications such as nano-mechanical resonators and tips of scanning probe instruments where they are subjected to mechanical vibrations. Continuum modeling is based on an elastic beam model. The interlayer van der Waals interactions are represented by Lennard-Jones potential. In finite element …

Nebraska Summary: S549 Challenger Mt555b, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary: S530 Case-Ih Jx1090u, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary 514: Challenger Mt425b Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Test 1865: Massey Ferguson 481 And 583 Diesel 8-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Nebraska Summary 510: Massey Ferguson 5435 Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Nebraska Summary 574: New Holland Tn95da Diesel 12-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Making Sense Of Nanocrystal Lattice Fringes, P. Fraundorf, Wentao Qin, Peter Moeck, Eric Mandell

Physics Faculty Publications and Presentations

The orientation dependence of thin-crystal lattice fringes can be gracefully quantified using fringe-visibility maps, a direct-space analog of Kikuchi maps [Nishikawa and Kikuchi, Nature (London) 121, 1019 (1928)]. As in navigation of reciprocal space with the aid of Kikuchi lines, fringe-visibility maps facilitate acquisition of crystallographic information from lattice images. In particular, these maps can help researchers to determine the three-dimensional lattice of individual nanocrystals, to 'fringe-fingerprint' collections of randomly oriented particles, and to measure local specimen thickness with only a modest tilt. Since the number of fringes in an image increases with maximum spatial-frequency squared, these strategies (with help …

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 And Experimentation Of Drying Of Adipose Derived Adult Stem Cells, Surbhi Mittal

LSU Master's Theses

Development of protocols for storing desiccated cells at ambient temperatures offers tremendous economic and practical advantages over traditional storage procedures such as cryopreservation and freeze-drying. An integrated frame work of experimentation and modeling is adopted in the present work to develop procedures for storage of adult stem cells at ambient temperature. As a first step, we have measured the post-rehydration membrane integrity of two passages, Passage-0 (P0) and Passage-1 (P1), of human adipose-derived stem cells (hASCs). hASCs were dried using a convective stage at three different drying rates (slow, moderate and rapid) in D-PBS with trehalose (50 mM) and glycerol …

A Study Of Distributed Clustering Of Vector Time Series On The Grid By Task Farming, Arun B. Nayar

LSU Master's Theses

Traditional data mining methods were limited by availability of computing resources like network bandwidth, storage space and processing power. These algorithms were developed to work around this problem by looking at a small cross-section of the whole data available. However since a major chunk of the data is kept out, the predictions were generally inaccurate and missed out on significant features that was part of the data. Today with resources growing at almost the same pace as data, it is possible to rethink mining algorithms to work on distributed resources and essentially distributed data. Distributed data mining thus holds great …

Mathematical Models For Estimating Volatile Chemical Emissions From Dredging Operations, Kenneth Alexander Fountain

LSU Master's Theses

Dredging operations have been a common remediation for contaminated sediment in an effort to reduce the harmful impact on the environment. The objective of this research was to create models used for estimating chemical release to air from remediating the Indiana Harbor and Canal (IHC) as three separate dredging operations; the Dredge Site, Exposed DM CDF, and Ponded CDF. The evaporative flux estimations are based on a two-resistance mass transport path inclusive of both the molecular diffusion in porous media and interfacial airside mass transport resistances. Several chemodynamic algorithms were used in calculating key transport parameters. Laboratory tests were performed …

Simulations And Experimental Analysis Of High-Aspect-Ratio Diffusive Micro-Mixers, Amit Maha

LSU Master's Theses

Passive (diffusional) mixing has been used in designing high-aspect-ratio micro-mixers for the purpose of performing the Liagase Detection Reaction (LDR). A simple model was used to design such mixers optimized for pressure drop or time required to deliver a prescribed volume of mixture. The types of mixers considered are simple, cheap, and durable and can perform over a broad range of volumetric flow rates at reasonably modest pressure drops. The fluids typically have a very low diffusion coefficient of=1.2x10^10m^2/s, and thus diffusional mixing can only be effective in high-aspect-ratio micro-channels. A realizable aspect ratio of 6 has been considered initially …

Developing Large-Scale Field-Programmable Analog Arrays For Rapid Prototyping, Tyson S. Hall, Christopher M. Twigg, Paul Hasler, David V. Anderson

Faculty Works

Field-programmable analog arrays (FPAAs) provide a method for rapidly prototyping analog systems. While currently available FPAAs vary in architecture and interconnect design, they are often limited in size and flexibility. For FPAAs to be as useful and marketable as modern digital reconfigurable devices, new technologies must be explored to provide area efficient, accurately programmable analog circuitry that can be easily integrated into a larger digital/mixed signal system. By leveraging recent advances in floating gate transistors, a new generation of FPAAs are achievable that will dramatically advance the current state of the art in terms of size, functionality, and flexibility.

Image Processing Techniques To Identify Predatory Birds In Aquacultural Settings, Uma Devi Nadimpalli

LSU Master's Theses

Bird predation is a major problem in aquaculture. A novel method for dispersing birds is the use of a vehicle that can sense and chase birds. Image recognition software can improve their efficiency in chasing birds. Three recognition techniques were tested to identify birds 1) image morphology 2) artificial neural networks, and 3) template matching have been tested. A study was conducted on three species of birds 1) pelicans, 2) egrets, and 3) cormorants. Images were divided into 3 types 1) Type 1, 2) Type 2, and 3) Type 3 depending upon difficulty to separate from the others in the …

Development And Model Formulation Of Scalable Carbon Nanotube Processes: Hipco And Comocat Process Models, Adedeji Ebenezer Agboola

LSU Master's Theses

Carbon nanotubes are seamless cylindrical tubes, consisting of carbon atoms arranged in a regular hexagonal structure. It is considered as the ultimate engineering material because of its unique and distinct electronic, mechanical and material characteristics. The discovery of these materials pioneered the nanotechnology revolution, which encompasses a broad and multidisciplinary spectrum, including nanomaterials, nanobiotechnology, and nanoelectronics. Hundreds of published articles of laboratory scale and pilot plant processes were reviewed that describe potential synthesis and post–synthesis purification methods for large scale production of carbon nanotubes. The main production technologies include electric arc discharge, laser vaporization, and catalytic chemical vapor deposition. These …

Semantic Classification Of Rural And Urban Images Using Learning Vector Quantization, Prakash Thulasiraman

LSU Master's Theses

One of the major hurdles in semantic image classification is that only low-level features can be reliably extracted from images as opposed to higher level features (objects present in the scene and their inter-relationships). The main challenge lies in grouping images into semantically meaningful categories based on the available low-level visual features of the images. It is important that we have a classification method that will handle a complex image dataset with not so well defined boundaries between clusters. Learning Vector Quantization (LVQ) neural networks offer a great deal of robustness in clustering complex datasets. This study presents a semantic …

Effects Of Magnetic Field On Micro Flames, Sumathi Swaminathan

LSU Master's Theses

The effect of a gradient magnetic field on a diffusion micro flame i.e. C3H8/air flame has been systematically studied to comprehend their interaction. A non-uniform magnetic field was produced in the air gap of an electromagnet and the C3H8/air flame corresponding to various flow velocities was subjected to the non-uniform field. The influence of the operating conditions on the fundamental characteristics of the diffusion flame, such as the flame structure, temperature distribution and the morphology of the soot produced in these flames have been thoroughly investigated. The flame structure and its luminosity were found to be influenced and the flame …

Experimental And Numerical Study Of Feeding Channel In Proton Exchange Membrane Fuel Cell, Abul Bashar Mahmud Hasan

LSU Master's Theses

The performance of a Proton Exchange Membrane Fuel Cell (PEMFC) using different feeding configurations has been studied, with a focus on the water flooding due to electrochemical reaction. Feeding channel or Bipolar plate in Proton Exchange Fuel Cell is a dominating part. As feeding channel keeps direct contact with the gas diffusion layer, it helps efficiently supplying fuel and air into the gas diffusion layer for efficient production of electricity. Experimental data have been taken at hydrogen flow rates of 20,40,60,80,100 sccm for various bipolar plate arrangements. Three bipolar plates, namely serpentine, straight channel and interdigitated designs, were arranged in …

Thermal Management Of The Lsu Micro Gas Chromatograph, Praveen K. Pasupuleti

LSU Master's Theses

Gas chromatography is a technique widely used for the separation and analysis of gas samples. Gas chromatographs are used for environmental maintenance, monitoring sophisticated biological analyses, and to separate components from a mixture of gases for mass spectrometer analysis. There has been a tremendous interest in miniaturization of gas chromatograph systems because of the potential for portability, faster response time, lower dead volume, lower power consumption, and lower cost of operation. Conventional gas chromatography keeps the column at a constant temperature during separation, which is called isothermal analysis. Temperature programming is a mode of gas chromatography in which the column …

Assimilation And Removal Of Phosphorus Within The Marshland Upwelling System, Derek A. Evans

LSU Master's Theses

The marshland upwelling system (MUS) is an alternative onsite wastewater system that was developed to treat domestic wastewater derived from coastal communities. Previous studies have researched the systems ability to treat fecal coliforms and nitrogen. The objectives of this research were to (1) assess the treatment efficiency of the MUS for removing both total phosphorus and orthophosphate, (2) provide preliminary design and operational guidelines for phosphorus removal, and (3) develop a parameter to project longevity of the MUS for treating phosphorus. Performance efficiency was compared for a system which operated for 23 months located in Bayou Segnette State Park and …

Power Supply Current [Ips] Based Testing Of Cmos Amplifier Circuit With And Without Floating Gate Input Transistors, Vanikumari Pulendra

LSU Master's Theses

This work presents a case study, which attempts to improve the fault diagnosis and testability of the power supply current based testing methodology applied to a typical two-stage CMOS operational amplifier and is extended to operational amplifier with floating gate input transistors*. The proposed test method takes the advantage of good fault coverage through the use of a simple power supply current measurement based test technique, which only needs an ac input stimulus at the input and no additional circuitry. The faults simulating possible manufacturing defects have been introduced using the fault injection transistors. In the present work, variations of …

The Effects Of Parkinson's On Fixational Stability, Erin L. Mallahan

Theses and Dissertations

Parkinson's disease (PD) is a progressive, neurological movement disorder. The stability of eye movements in PD is not well understood but many patients report difficulty doing tasks that require stabilized fixation and gaze. The ability to stabilize an image on the retina is critical is acquiring visual information. The purpose of this study was to compare the stability of fixational eye movements of PD patients to those of age-matched controls. Eye movements during simple fixation tasks were recorded from 66 subjects (ages 52 to 84), and 36 age-matched controls (ages 58-85). The absolute velocity of the fixational eye movements were …