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Model-Based Nonlinear Control Of Active Tilting-Pad Bearings, An Wu 2010 Louisiana State University and Agricultural and Mechanical College

Model-Based Nonlinear Control Of Active Tilting-Pad Bearings, An Wu

LSU Doctoral Dissertations

A promising mechanical bearing candidate for active operation is the tilting-pad bearing. The proposed active tilting-pad bearing has linear actuators that radially translate each pad. The use of feedback control in determining the actuator forces allows for the automatic, continuous adjustment of the pad position during the operation of the rotating machine. In the first part of the dissertation, we develop a nonlinear dynamic model of the active bearing system. The hydrodynamic force produced by the fluid film is modeled as a nonlinear, squeeze-film damper plus repellent spring. A model-based nonlinear controller is then designed to exponentially regulate the rotor ...


Macroinstability And Perturbation In Turbulent Stirred Tank Flows, Somnath Roy 2010 Louisiana State University and Agricultural and Mechanical College

Macroinstability And Perturbation In Turbulent Stirred Tank Flows, Somnath Roy

LSU Doctoral Dissertations

Impeller stirred tank reactors (STRs) are commonly used in the chemical processing industries for a variety of mixing and blending technologies. In this research, a numerical study of flow and mixing inside turbulently agitated STRs are carried out. An immersed boundary method (IBM) is utilized to represent moving impeller geometries in the background of multi-block structured curvilinear fluid. The IBM This curvilinear-IBM methodology is further combined with the large eddy simulation (LES) technique to address the issue of modeling unsteady turbulent flows in the STR. Verification of the combined IBM-LES implementation strategy in curvilinear coordinates is done through comparisons with ...


A Study Of Hough Transform For Weld Extraction, Rakesh Gunaseelan 2010 Louisiana State University and Agricultural and Mechanical College

A Study Of Hough Transform For Weld Extraction, Rakesh Gunaseelan

LSU Master's Theses

The process of joining metals is called welding. At times, selecting a poor quality material or improper usage of welding technologies may cause defects in welded joints. Some of these welded joints have to be tested nondestructively, because their failure can cause lot of damage, for instance in power plants. Radiography is a very common method for non-destructive testing of welds. It is done by certified weld inspectors who have knowledge about weld flaws, looking at the radiograph of the welded joint with naked eye. The judgment of the weld inspector can be biased; subjective, because it is dependent on ...


Antisense Silver Nanoparticles For Photo-Activated Gene Silencing, Paige Kathleen Brown 2010 Louisiana State University and Agricultural and Mechanical College

Antisense Silver Nanoparticles For Photo-Activated Gene Silencing, Paige Kathleen Brown

LSU Master's Theses

The unique properties of noble metal nanoparticles, which include tunable electronic and photonic characteristics, contribute to their potential as novel delivery vectors with enhanced drug stability, cell uptake, and photo-activated functionalities. Silver, as one of best surface-enhancing substrates available for bulk nanostructure synthesis, is a prime choice for investigations of metal nanohybrids as antisense therapy vehicles with special surface plasmon resonance (SPR) enabled functional attributes. The singular photonic properties of silver nanoparticles (SNPs) may contribute to ease of delivery confirmation and in situ photo-activation of protected cargo packed on particle surfaces. Here we show the synthesis and characterization of 40-80nm ...


Effect Of Management Awareness Of Safety Climate Concept On Organizational Safety Climate, Christopher Michael Holzner 2010 Louisiana State University and Agricultural and Mechanical College

Effect Of Management Awareness Of Safety Climate Concept On Organizational Safety Climate, Christopher Michael Holzner

LSU Master's Theses

Safety research and practice have shifted focus away from accident rates and accident causal information to a more proactive approach that may predict organizational safety trends. This proactive approach involves the concept of an organizational safety culture and the use of surveys to measure organizational safety climate or „snapshot‟ of the organizational safety culture. Surveys were administered to line workers, supervisors, and managers at a modular home manufacturing company before and after safety climate information was presented to supervisors and managers in an attempt to measure the effect of the supervisors‟ and managers‟ increased awareness of the factors that define ...


Lattice Boltzmann Modeling For Shallow Water Equations Using High Performance Computing, Kevin Tubbs 2010 Louisiana State University and Agricultural and Mechanical College

Lattice Boltzmann Modeling For Shallow Water Equations Using High Performance Computing, Kevin Tubbs

LSU Doctoral Dissertations

The aim of this dissertation project is to extend the standard Lattice Boltzmann method (LBM) for shallow water flows in order to deal with three dimensional flow fields. The shallow water and mass transport equations have wide applications in ocean, coastal, and hydraulic engineering, which can benefit from the advantages of the LBM. The LBM has recently become an attractive numerical method to solve various fluid dynamics phenomena; however, it has not been extensively applied to modeling shallow water flow and mass transport. Only a few works can be found on improving the LBM for mass transport in shallow water ...


Experimental And Numerical Analysis Of Fuel Cells, Abul Bashar Mahmud Hasan 2010 Louisiana State University and Agricultural and Mechanical College

Experimental And Numerical Analysis Of Fuel Cells, Abul Bashar Mahmud Hasan

LSU Doctoral Dissertations

Fuel Cells are attractive power source for use in electronic applications. Physical phenomena (water generation, saturation effect in fuel cell, poisoning, and thermal stress) are studied that governs the operation of a Proton Exchange Membrane Fuel Cell (PEMFC) and Solid Oxide Fuel cell (SOFC). Additionally, experimental studies and numerical simulations on PEMFC gas flow channel, the determination of the impact of the single channel fuel cell are presented. Furthermore, preliminary study is done for the application of APS (Air Plasma Spray) to SOFC and adhesion of anode and cathode with electrolytes for the determination of parameters involved in manufacturing the ...


Antioxidant Nanoparticles As Delivery Systems, Carlos Ernesto Astete R. 2010 Louisiana State University and Agricultural and Mechanical College

Antioxidant Nanoparticles As Delivery Systems, Carlos Ernesto Astete R.

LSU Doctoral Dissertations

The goal of the study was to develop antioxidant polymeric nanoparticles as a new delivery system for food and pharmaceutical applications. Natural antioxidants like alpha-tocopherol, vitamin C, and carnosine, are responsible to protect biological systems against free radicals attack. The conjugation of vitamin C-vitamin E (EC) and alpha-tocopherol-carnosine (VECAR) were performed to obtain antioxidant surfactants which were used for polymeric nanoparticle synthesis. The surfactant made of á-tocopherol (vitamin E) and ascorbic acid (vitamin C) of antioxidant properties dubbed as EC was used to make poly(lactic-co-glycolic) acid (PLGA) nanoparticles. Self-assembled EC nanostructures and PLGA-EC nanoparticles were made by nanoprecipitation, and ...


Point-Of-Care Immunoassay System Using Carbon Nanotube Labels, Adeyabeba Abera 2010 Louisiana State University and Agricultural and Mechanical College

Point-Of-Care Immunoassay System Using Carbon Nanotube Labels, Adeyabeba Abera

LSU Doctoral Dissertations

The goal of this research was to develop enhanced signal detection mechanisms for immunosensing using carbon nanotubes (CNTs). The utilization of CNT labels for direct electrical measurement was implemented on lateral flow system and microfluidic integrated interdigitated array microelectrodes. These sensing mechanisms in simple and miniaturized system provided higher sensitivity and autonomous flow control for rapid detection aimed at point-of-care diagnostics. Specific functionalization protocols were carried out to chemically modify the surface of the CNTs for uniform dispersion and antibody conjugation in aqueous solution. Surfactant assisted dispersion of the CNTs was studied using PVP and PEG. Covalent conjugation of antibodies ...


Practical Simulation Application: Evaluation Of Process Control Parameters In Twisted-Pair Cables Manufacturing System, Amr Mahfouz, Said Hassan, Amr Arisha 2010 Technological University Dublin

Practical Simulation Application: Evaluation Of Process Control Parameters In Twisted-Pair Cables Manufacturing System, Amr Mahfouz, Said Hassan, Amr Arisha

Articles

Intensive competition and rapid technology development of Twisted-Pair Cables (TPC) industry have left no room for competing manufacturers to harbour system inefficiencies. TPC are used in various communication and networks hardware applications; their manufacturing facilities face many challenges including various product configurations with different equipment settings, different product flows and Work in Process (WIP) space limitations. The quest for internal efficiency and external effectiveness forces companies to align their internal settings and resources with external requirements/orders, or in different words, significant factors must be set appropriately and identified prior to manufacturing processes. Integrated definition models (IDEF0, IDEF3) in conjunction ...


Defending Privacy: The Development And Deployment Of A Darknet, Conor McManamon, Fredrick Mtenzi 2010 Technological University Dublin

Defending Privacy: The Development And Deployment Of A Darknet, Conor Mcmanamon, Fredrick Mtenzi

Conference papers

New measures imposed by governments, Internet service providers and other third parties which threaten the state of privacy are also opening new avenues to protecting it. The unwarranted scrutiny of legitimate services such as file hosters and the BitTorrent protocol, once relatively unknown to the casual Internet user, is becoming more obvious. The darknet is a rising contender against these new measures and will preserve the default right to privacy of Internet users. A darknet is defined in the context of file sharing as a network which operates on top of another network such as the Internet for the purpose ...


Helmsman, Set A Course : Using A Compass And Rfid Tags For Indoor Localisation And Navigation, Yan Li, Brian Mac Namee, John D. Kelleher 2010 Technological University Dublin

Helmsman, Set A Course : Using A Compass And Rfid Tags For Indoor Localisation And Navigation, Yan Li, Brian Mac Namee, John D. Kelleher

Conference papers

Localisation and navigation are still two of the most important issues in mobile robotics. In certain indoor application scenarios RFID (radio frequency identification)-based absolute localisation has been found to be especially successful in supporting navigation. In this paper we evaluate the feasibility of an RFID and compass based approach to robot localisation and navigation for indoor environments that are dominated by corridors. We describe our system and evaluate its performance in a small, but full-scale, test environment.


Liquid Crystal Display Modes In A Nontilted Bent-Core Biaxial Smectic Liquid Crystal, Mamatha Nagaraj, Yuri Panarin, J. K. Vij, C. Keith, C. Tschierske 2010 Trinity College Dublin, Ireland

Liquid Crystal Display Modes In A Nontilted Bent-Core Biaxial Smectic Liquid Crystal, Mamatha Nagaraj, Yuri Panarin, J. K. Vij, C. Keith, C. Tschierske

Articles

Liquid crystal display (LCD) modes associated with the rotation of the secondary director in nontilted, biaxial smectic phase of an achiral bent-core compound are demonstrated. For LCDs, we find that at least four display modes are possible using SmAPA phase of the studied material, in which the minor directors in adjacent layers are aligned antiferroelectrically. The advantages of these modes include low driving field (1–2 V/ µm), high contrast ratio 1000:1, relatively fast switching time of 0.5 ms and continuous gray scale. The molecular short axis or the polar axis in a negative dielectric, biaxial material is ...


Ultrasound-Assisted Swnts Dispersion: Effects Of Sonication Parameters And Solvent Properties, Qiaohuan Cheng, Sourabhi Debnath, Elizabeth Gregan, Hugh Byrne 2010 Technological University Dublin

Ultrasound-Assisted Swnts Dispersion: Effects Of Sonication Parameters And Solvent Properties, Qiaohuan Cheng, Sourabhi Debnath, Elizabeth Gregan, Hugh Byrne

Articles

Ultrasonication is widely used for preparing Single-Walled Carbon Nanotube (SWNT) dispersions in different solvent media and it has been shown to play a critical role in dispersing and debundling SWNTs. The strong shear force that can exfoliate the SWNT bundles during sonication comes from cavitation, which entails a process of bubble formation, growth, and collapse. The efficiency of the cavitation process is closely correlated to many solvent parameters, including vapor pressure, viscosity, and surface tension, as well as the sonication frequency, intensity, and time. In this study, SWNTs were dispersed in a range of organic solvents assisted by tip sonication ...


Unconventional Uses Of Cantilevers For Chemical Sensing In Gas And Liquid Environments, Isabelle Dufour, Fabien Josse, Stephen M. Heinrich, C. Lucat, C. Ayela, F. Ménil, Oliver Brand 2010 Université de Bordeaux

Unconventional Uses Of Cantilevers For Chemical Sensing In Gas And Liquid Environments, Isabelle Dufour, Fabien Josse, Stephen M. Heinrich, C. Lucat, C. Ayela, F. Ménil, Oliver Brand

Civil and Environmental Engineering Faculty Research and Publications

Microcantilevers used as (bio)chemical sensors are usually coated with a chemically sensitive layer. The coated devices operate either in a static bending regime or in a dynamic flexural mode. While the coated devices operate generally well in both the static and dynamic mode, they do suffer from certain shortcomings depending on the medium of operation and the application, including lack of selectivity and of reversibility of the sensitive coating and a reduced quality factor due to the surrounding medium. In particular, the performance of microcantilevers excited in their standard out-of-plane dynamic mode drastically decreases in viscous liquid media. Moreover ...


An Investigation Of The Rwpe Prostate Derived Family Of Cell Lines Using Ftir Spectroscopy, M. Baker, Colin Clarke, D. Demoulin, J. Nicolson, Fiona Lyng, Hugh Byrne, C. Hart, M. Brown, N. Clarke, P. Gardner 2010 University of Manchester

An Investigation Of The Rwpe Prostate Derived Family Of Cell Lines Using Ftir Spectroscopy, M. Baker, Colin Clarke, D. Demoulin, J. Nicolson, Fiona Lyng, Hugh Byrne, C. Hart, M. Brown, N. Clarke, P. Gardner

Articles

Interest in developing robust, quicker and easier diagnostic tests for cancer has lead to an increased use of Fourier transform infrared (FTIR) spectroscopy to meet that need. In this study we present the use of different experimental modes of infrared spectroscopy to investigate the RWPE human prostate epithelial cell line family which are derived from the same source but differ in their mode of transformation and their mode of invasive phenotype. Importantly, analysis of the infrared spectra obtained using different experimental modes of infrared spectroscopy produce similar results. The RWPE family of cell lines can be separated into groups based ...


Resonant Mie Scattering (Rmies) Correction Of Infrared Spectra From Highly Scattering Biological Samples Analyst, Paul Bassan, Achim Kohler, Harald Martens, Joe Lee, Hugh Byrne, Paul Dumas, Ehsan Gazi, Michael Brown, Noel Clarke, Peter Gardner 2010 University of Manchester

Resonant Mie Scattering (Rmies) Correction Of Infrared Spectra From Highly Scattering Biological Samples Analyst, Paul Bassan, Achim Kohler, Harald Martens, Joe Lee, Hugh Byrne, Paul Dumas, Ehsan Gazi, Michael Brown, Noel Clarke, Peter Gardner

Articles

Infrared spectra of single biological cells often exhibit the “dispersion artefact” observed as a sharp decrease in intensity on the high wavenumber side of absorption bands, in particular the Amide I band at ~1655 cm-1, causing a downward shift of the true peak position. The presence of this effect makes any biochemical interpretation of the spectra unreliable. Recent theory has shed light on the origins of the ‘dispersion artefact’ which has been attributed to resonant Mie scattering (RMieS). In this paper a preliminary algorithm for correcting RMieS is presented and evaluated using simulated data. Results show that the ‘dispersion artefact ...


Applications Of Ultrafine Powder Coatings, A.S. Mohammad Sayem Mozumder 2010 Western University

Applications Of Ultrafine Powder Coatings, A.S. Mohammad Sayem Mozumder

Digitized Theses

Powder coatings have emerged as an alternative to the conventional liquid coatings when environmental regulations become stricter every year. The advantage of powder coatings mainly renders to their solvent-free formulations, because solvent(s) used in liquid coatings are to be evaporated to environment contributing to the total volatile organic compounds (VOCs) emissions. Although advantageous, until recently, powder coating was not able to provide surface finishes comparable to the liquid coatings. However, when ultrafine powders (particularly, in the size range of 15-25 µm) becomes flowable with the aid of nano-additive(s), ultrafine powder coatings (UPCs) came into business with its thinner ...


A Machine Learning Approach To Hierarchical Categorisation Of Auditory Objects, William Coleman, Sarah Jane Delany, Charlie Cullen, Ming Yan Dr. 2010 Technological University Dublin

A Machine Learning Approach To Hierarchical Categorisation Of Auditory Objects, William Coleman, Sarah Jane Delany, Charlie Cullen, Ming Yan Dr.

Articles

With the advent of new audio delivery technologies comes opportunities and challenges for content creators and providers. The proliferation of consumption modes (stereo headphones, home cinema systems, ‘hearables’), media formats (mp3, CD, video and audio streaming) and content types (gaming, music, drama & current affairs broadcasting) has given rise to a complicated landscape where content must often be adapted for multiple end-use scenarios. The concept of object-based audio envisages content delivery not via a fixed mix but as a series of auditory objects which can then be controlled either by consumers or by content creators & providers via accompanying metadata. Such a ...


Nonlinear Circuit Analysis Via Perturbation Methods And Hardware Prototyping, Kofi Odame, P. E. Hasler 2010 Dartmouth College

Nonlinear Circuit Analysis Via Perturbation Methods And Hardware Prototyping, Kofi Odame, P. E. Hasler

Dartmouth Scholarship

Nonlinear signal processing is necessary in many emerging applications where form factor and power are at a premium. In order to make such complex computation feasible under these constraints, it is necessary to implement the signal processors as analog circuits. Since analog circuit design is largely based on a linear systems perspective, new tools are being introduced to circuit designers that allow them to understand and exploit circuit nonlinearity for useful processing. This paper discusses two such tools, which represent nonlinear circuit behavior in a graphical way, making it easy to develop a qualitative appreciation for the circuits under study.


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