Engineering Science and Materials Commons^™

Vorticella: A Protozoan For Bio-Inspired Engineering, Sangjin Ryu, Rachel E. Pepper, Moeto Nagai, Danielle C. France

Department of Mechanical and Materials Engineering: Faculty Publications

In this review, we introduce Vorticella as a model biological micromachine for microscale engineering systems. Vorticella has two motile organelles: the oral cilia of the zooid and the contractile spasmoneme in the stalk. The oral cilia beat periodically, generating a water flow that translates food particles toward the animal at speeds in the order of 0.1–1 mm/s. The ciliary flow of Vorticella has been characterized by experimental measurement and theoretical modeling, and tested for flow control and mixing in microfluidic systems. The spasmoneme contracts in a few milliseconds, coiling the stalk and moving the zooid at 15–90 mm/s. Because the …

Investigation Of Electrical Defects Arising From Excessive Sidewall Force And Excessive Tensile Strain On Power Cables, Darren Mcconnon, Joseph Kearney, Tom Looby, James O'Shaughnessy

Conference papers

The study includes a comprehensive review of the existing literature and guidelines regarding the effects of sidewall force and tensile strain on power cables during installation. The most appropriate diagnostic test methods required to analyse these effects are also assessed. The results of tests and analysis of the existing literature are then combined in an attempt to determine a realistic basis for guidelines and recommendations relevant to cable installation forces.

A Review Of Control Methodologies For Dynamic Glazing, Eoin D. Mclean, Brian Norton, Derek Kearney, Philippe Lemarchand

Conference papers

With adaptive building façade technologies, a building envelope can provide a comfortable indoor environment under varying external conditions with minimal additional heating or cooling. The control strategy applied to the adaptation of the façade is a key determining factor in the successful integration of these technologies into a building. The building envelope plays a key role in regulating light, heat and mass transfer from the outdoor environment to the indoor. Dynamic glazing can be used to adjust the amount of solar radiation entering a building. The control strategies that ultimately determine the success of these switchable technologies to affect a …

Comparison Of Extruder Systems For 3d Printer Filament Fabrication, Adriana Ramirez

Open Access Theses & Dissertations

Additive Manufacturing (AM) has grown in popularity over the past thirty years, due to its versatility, short design to product cycle, and capability to fabricate complex geometries, which cannot otherwise be produced. There exist several platforms that are able to print objects composed of different materials, making this technology significant in different fields such as: automotive, aerospace, medical, electronics, amongst others. Though several types of AM technologies are available, the expiration of the patents on fused deposition modeling (FDM) in 2009 has led to a widespread use of this platform in academia and home use settings.

Widespread use of FDM-type …

Material Behavior Of Window 7 Carrier Panel Tiles And Thermal Pane Fragments Recovered From The Space Shuttle Columbia, Brenda Roseanne Arellano

Open Access Theses & Dissertations

Since the end of the space shuttle program, a new generation spacecraft has been developed to transport humans back into space. NASAâ??s Orion will carry a crew beyond low-earth orbit and the exploration of Mars may be possible in the future. Space safety becomes significant with human spaceflight and the risks are high. However, aerospace materials may provide opportunities to prevent future disasters. When the space shuttle Columbia disintegrated during re-entry in 2001, thousands of debris were collected for analysis. In contrast, when the Challenger space shuttle broke apart in 1986, all shuttle debris were buried. These tragic disasters are …

The Interplay Between Grain Size And Austenite Stability On Deformation Behavior Of High Strength-High Ductility Combination Nanostructured Stainless Steel, Venkata Sai Ananth Challa

Open Access Theses & Dissertations

The concept of phase reversion involving severe cold deformation of metastable austenite to generate strain-induced martensite, followed by temperature-time annealing sequence, was used to obtain varying grain size from nanograined/ultrafine-grained (NG/UFG) to coarse-grained (CG) regime. This concept was used to obtain â??high strength-high ductilityâ?? combination in nano/ultrafine-grained (NG/UFG) austenitic stainless steel. Using this concept, the objective of the study is to elucidate the dependence of grain size on deformation mechanisms and deformation-induced microstructural changes. The objective was accomplished by combining depth-sensing nanoindentation experiments conducted at various strain rates, and interrupted tensile testing at various strain and post-mortem analyses of deformed …

Dft Study Of Adsorption Of Trimetallic Endohedral Fullerenes On Graphene, Nakul Nitin Karle

Open Access Theses & Dissertations

A density functional theory (DFT) study on the geometric and electronic structure of C60 and Sc3N@C80 along with their adsorption on pristine single layer graphene (SLG) is presented. C60 is found to adsorb in two nearly degenerate configurations: (i) with a pentagon facing the SLG, which is the most stable one, and (ii) with a hexagon facing the SLG in a face-to-face perfect alignment, rarely common in Ï?â??Ï? interactions, 0.06 eV higher in energy. The calculated binding energy of 0.76 eV, which includes dispersion effects, is in good agreement with previous theoretical and experimental reports. On the contrary, Sc3N@C80 adsorption …

Processing Of Ultra-Thin Film Of Un Modified C60 Fullerene Using The Langmuir-Blodgett Technique. Effect Of Structure On Stiffness And Optoelectric Properties, Hasanain Basim Altalebi

Browse all Theses and Dissertations

Monolayer films of C60 fullerene were for the first time produced successfully by using the Langmuir-Blodgett technique. The processing parameters were optimized and the structure of these films has been investigated using Scanning Tunneling Microscopy (STM) and Atomic Force Microscopy (AFM). Film stiffness was measured to be in the range of 15 MPa to 32 MPa depending on the nature of the solvent used to process the films. Optical transparency and electrical performance have been measured and correlated to the film structure. While 100% transparent, the film measured conductivity was in the range of 1013 S/m, that is orders of …

An Experimental Investigation Of Residual Stress Development During Selective Laser Melting Of Ti-6al-4v, Nathan Charles Levkulich

Browse all Theses and Dissertations

Selective laser melting (SLM) is an additive manufacturing (AM) process that gives rise to large thermal gradients and rapid cooling rates that lead to the development of undesirable residual stress and distortion. In this work, a number of different techniques (i.e., x-ray-diffraction, hole-drilling, layer-removal, and contour) were utilized to establish the effect of process parameters on residual stress development during SLM of Ti-6Al-4V. The measurements indicated that higher laser power, slower scan speed, smaller stripe width, reduced substrate overhang, and reduced build plan area each reduce the level of residual stress. In addition, the correlation between microstructure, crystallographic texture, and …

Analytical Strip Method For Thin Cylindrical Shells, John T. Perkins

Theses and Dissertations--Civil Engineering

The Analytical Strip Method (ASM) for the analysis of thin cylindrical shells is presented in this dissertation. The system of three governing differential equations for the cylindrical shell are reduced to a single eighth order partial differential equation (PDE) in terms of a potential function. The PDE is solved as a single series form of the potential function, from which the displacement and force quantities are determined. The solution is applicable to isotropic, generally orthotropic, and laminated shells. Cylinders may have simply supported edges, clamped edges, free edges, or edges supported by isotropic beams. The cylindrical shell can be stiffened …

Redox-Active Solid State Materials And Its Biomedical And Biosensing Applications, Ankur Gupta

Electronic Theses and Dissertations

Reactive oxygen species (ROS) are byproducts of physiological processes in human body, and strengthened production of ROS is known to cause acute conditions such as inflammation, aging, Alzheimer's disease, melanoma and ovarian cancer, fibrosis and multiple sclerosis. Therefore, early detection of ROS at nanomolar concentration (at cellular level) and developing more potent antioxidants is essential for regular health monitoring. As an example, ROS are also responsible for inflammation reactions at orthopedic implants-tissue interface triggered by wear debris. Inflammation induced by ROS results in revision surgery. Coatings of redox-active materials exhibiting antioxidant properties on implants have potential to mitigate the inflammation …

Developing An Insider Threat Experimental Environment, Eric Ortiz

Electronic Theses and Dissertations

Simulated, 3D gaming environments have been used for a wide-range of applications including training, entertainment, and experimentation in an assortment of domains for some time. This can be attributed to their unique ability to emulate multifaceted situations that may be difficult to control, while affording participants the opportunity to operate in a relatively safe environment. In cybersecurity research, investigation of insider threat behavior is an endeavor that has received little attention in terms of available environments and resources for experimental manipulation. This research effort aimed to close this gap. A simulated, 3D gaming environment and accompanying scenarios were developed for …

Frontal Crash Analysis Of A Conformable Cng Tank Using Finite Element Analysis, Datta Sandesh Manjunath

Dissertations, Master's Theses and Master's Reports

The purpose of this study is to computationally model and analyze a Conformable Compressed Natural Gas (CNG) fuel tank for frontal crashes using Finite Element Analysis. Researchers have developed a CNG fuel tank, which is conformable, non-conventional and non-cylindrical. This tank increases cost efficiency, volumetric efficiency and cargo efficiency in CNG vehicle applications. A lightweight pickup truck (2015 Chevrolet Silverado) has been used to integrate the CNG tanks and field-testing has been conducted to demonstrate the application.

The report mainly focuses on the effective finite element modeling of the chassis, brackets and tanks using HYPERMESH and RADIOSS. The frontal crash …

Easily Verifiable Controller Design With Application To Automotive Powertrains, Mohammad Reza Amini

Dissertations, Master's Theses and Master's Reports

Bridging the gap between designed and implemented model-based controllers is a major challenge in the design cycle of industrial controllers. This gap is mainly created due to (i) digital implementation of controller software that introduces sampling and quantization imprecisions via analog-to-digital conversion (ADC), and (ii) uncertainties in the modeled plant’s dynamics, which directly propagate through the controller structure. The failure to identify and handle these implementation and model uncertainties results in undesirable controller performance and costly iterative loops for completing the controller verification and validation (V&V) process.

This PhD dissertation develops a novel theoretical framework to design controllers that are …

Reuse And Recycling Drill Cuttings In Concrete Applications, Maziar Foroutan

LSU Master's Theses

Drill cutting (DC) is a major waste produced during petroleum extraction, which could present a major source of contamination to soil and groundwater, if not disposed of properly. The objective of this study aims to test the hypothesis that drill cuttings can be incorporated as an aggregate in the production of concrete, and is suitable for use in controlled, low-strength material (CLSM) for non-structural applications. To achieve this objective, the physical and consensus properties of drill cuttings were characterized. Concrete mixtures were designed for CLSM applications with and without drill cuttings sampled from two sources. Prepared concrete mixes were then …

Computational Studies On Fluid And Particle Dynamics, Chenguang Zhang

LSU Doctoral Dissertations

This dissertation is divided into two parts. The first part includes chapter 2 to 4, which focus on development and application of numerical algorithm on particle and fluid simulation. Starting with a pure granular system in a driven cavity setup (Chapter 2), we move on to the immersed boundary simulation of fluid solid interaction (Chapter 3). This part ends with a coupled immersed boundary-discrete particle implementation. The second part includes Chapter 5 and Appendix A, each deals with an independent problem and focuses more on the theoretical aspects. Chapter 5 deals with a classic fluid dynamics problem of thermal wave …

Tribological And Dynamical Study Of An Automotive Transmission System, Meng Li

LSU Doctoral Dissertations

The transmission system is critical for automotive and heavy duty equipment due to its prominent role in the powertrain system, which is often challenged with degraded torque capacity and harsh dynamic response. Simulation-guided design can provide appropriate guidelines to resolve these problems with virtual analyses. In current study, the tribological and dynamical study of an automatic transmission is performed at two levels: a wet clutch and powertrain. In this dissertation, tribological study is performed for a wet clutch based on the thermohydrodynamic (THD) analysis that takes the following factors into account. • The groove effect (depth, area, and pattern) is …

Healing Mechanism Investigation Of Self-Healing Concrete By Microencapsulated Calcium Nitrate, Gabriel Andres Arce Amador

LSU Doctoral Dissertations

Durability of reinforced concrete structures depends highly on the integrity of the concrete which protects the structure from the environment. However, concrete is a brittle material and as such it is prone to cracking which allows for detrimental agents to penetrate the structure and produce early deterioration. Embedding microcapsules with chemical healing agents in concrete materials for self-healing applications as well as implementing SMAs as reinforcement of concrete structures for self-closing of cracks are both state-of-the-art techniques with enormous potential for enhancement of concrete infrastructure durability. In this work, both techniques are combined as an alternative for superior self-healing of …

Integration Of Shape-Memory Alloys And Self-Healing Microcapsules To Enhance Concrete Durability, Luis Adolfo Bonilla

LSU Doctoral Dissertations

Self-healing is a term that has not been used for building material until a few decades ago. The concept of developing a material that mimics what living organisms do, such as identify and repair damage, rather than interesting, constitutes a necessity in today’s deteriorated infrastructure. Concrete is one of the main building blocks that support our society’s roads, buildings, and dams. Increasing the service life of such structures will have an important socio-economic benefit in our society. Self-healing methods in concrete have been studied in order to minimize human intervention in maintenance procedures. Previous research in this area has provided …

Performance Evaluation And Characterization Of Encapsulated Calcium Nitrate For Self-Healing Concrete Applications, Jose Eduardo Milla

LSU Doctoral Dissertations

Self-healing concrete through microencapsulated calcium nitrate is a novel approach to enhance durability and decrease the costs associated with maintenance and repairs. However, to fully assess the potential of this technology, there are many questions to be answered, ranging from identifying the microcapsule properties that are successfully carry the healing agent, to the effect of the microcapsule size, concentration (by weight of cement), and morphology have on the intrinsic concrete material properties and self-healing potential. Hence, the objectives of this study were to: (a) Develop a microencapsulation procedure for calcium nitrate as the healing agent; (b) Measure the short-term healing …