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Title: EXPERIMENTAL STUDY, TIME-RESOLVED OBSERVATION, AND ANALYSIS OF NANOSECOND LASER ABLATION AND LASER-INDUCED PLASMA
Creator: Zhou, Yun
Date: 2013, 2013-05
Description: For lasers, there exist many current and potential competitive applications in the areas of manufacturing, materials processing, and so on....
Show moreFor lasers, there exist many current and potential competitive applications in the areas of manufacturing, materials processing, and so on. Nanosecond (ns)-pulsed lasers are often seen in these applications. This dissertation presents the experimental study, time-resolved observation and analysis of nanosecond laser ablation and laser-induced plasma due to ablation, and the analysis is based on physics-based numerical models. Specifically, the following topics have been studied: (1). Plasma induced by ablation using long-duration nanosecond laser pulse Plasma is often produced in laser-material interactions, and may play an important role in many laser-based or laser-assisted technologies, such as laser shock peening (LSP), laser micromachining (through the laser ablation process), laser-induced breakdown spectroscopy (LIBS), and laser propulsion, etc. However, despite the previous work in the literature, the study is still limited for the plasma induced by the ablation process using long nanosecond laser pulses (with durations on the order of ~100 ns). In this dissertation, investigations have been performed on this kind of plasma through fast photography (imaging) and emission spectroscopy techniques, and the experimental results have been analyzed using physics-based computational models. Based on the investigations, the following major interesting findings have been obtained under the investigated conditions: (i) Two high radiation intensity regions are observed in the plasma, and one of them disappears soon after laser pulse ends. The research work shows that this phenomenon is related to the vaporization process from the target surface and the confinement effect of the ambient air. (ii) Laser-induced plasma xvii backward growth phenomenon occurs for target ablation using 100-ns laser pulses, but not for that using 200-ns pulses. The investigation shows that the underlying mechanism is the backward growth of the boundary of the high temperature region without actual backward motion of vapor material. (iii) Under the studied conditions, the core region of the plasma (~100 μm above the laser-ablated target) has relatively low temperatures as compared to some other regions of the plasma, which contradicts the common intuition. (2). Semiconductor ablation utilizing infrared (IR) nanosecond laser pulses Semiconductor micromachining through laser ablation may have the advantages of high spatial resolution, high processing efficiency, good flexibility, and no tool wear. However, most of the prior investigations in the literature on ns laser ablation of semiconductors often employ lasers at the ultraviolet (UV) or visible wavelength. The work using IR ns lasers is limited, but IR ns lasers may often have lower cost and require less external energy consumption to produce the same average laser power output. In this dissertation, the ablation of semiconductors using IR ns lasers has been studied through time-resolved observations (fast photography) and the results have been analyzed utilizing physics-based numerical models. The research work shows that the ablation mechanism under the studied conditions is the surface vaporization process during the early stage followed by the subsequent liquid ejection process that occurs at a later time. The research work and analysis shows that the underlying mechanism for the observed liquid ejection should be due to the spatial gradient of the pressure exerted on the target surface, instead of phase explosion. (3). Laser-induced backside ablation (LIBA) of sapphire with IR ns laser pulses xviii LIBA may potentially provide a good solution for high-quality and highefficiency micromachining of wide-band-gap dielectrics (WBGD). However, the prior work on LIBA of sapphire (which is a very important WBGD material) using low-cost IR ns lasers has been rarely reported. This kind of work has been carried out in this dissertation, and the investigation shows that under the studied conditions LIBA can produce very high material removal efficiency and reasonably good quality of machining without obvious chemical contamination coming from the employed backing layer. The ablation rate and damage threshold are measured under different laser parameters, and the research work may provide useful information for the applications of LIBA in practical areas using IR ns lasers that may often have relatively lower cost than UV or visible ns lasers.
PH.D in Mechanical and Aerospace Engineering, May 2013
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Title: The yield of acetic acid as influenced by temperature in wood distillation
Creator: Marx, Walter L.
Date: 2009, 1913
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/yieldofaceticaci00marx
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 22

Title: PREPARATION FOR IMPLANTATION OF AN INTRACORTICAL VISUAL PROSTTIESIS IN A HUMAN: WORKING TOWARDS SATURATION
Creator: Troyk, Melissa J
Date: 2017, 2017-07
Description: The research focused on restoring visual perception via a vision prosthetic is progressing at a rapidly advancing rate. Previous research on...
Show moreThe research focused on restoring visual perception via a vision prosthetic is progressing at a rapidly advancing rate. Previous research on the experiences and perspectives of past, current, and potential vision prosthesis users has demonstrated that the decision to obtain a vision prosthetic is driven by a variety of unique factors and variables that merge with one another during the process of deciding to participate in clinical vision prosthesis research (Lane, Huyck, Troyk, & Schug, 2012; Lane, Nitsch, Huyck, Troyk, & Schug, 2014; Lane, Nitsch, & Troyk, 2015). The purpose of the current study was twofold: 1) to determine if our understanding of the experiences and perspectives of potential vision prosthesis users was nearing saturation, and 2) to understand the perspectives of potential vision prosthesis users who are veterans. Data were analyzed in accordance with qualitative analysis procedures. Results identified several new themes and subthemes that were determined to be important to our understanding of potential users’ perspectives of an intracortical vision prosthesis device. A preliminary framework is proposed for understanding how the identified themes and subthemes merge during the process of deciding to participate in an experimental vision prosthesis human clinical trial. The results demonstrated that while progress has been made, there is still more to learn about blind individuals’ perspectives of vision prostheses and how they would decide to participate in vision prosthesis research.
M.S. in Psychology, July 2017
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Title: Some commutation phenomena of direct current machinery
Creator: Clark, F. C.
Date: 2009, 1905
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/somecommutationp00clar
Thesis (B.S.)--Armour Institute of Technology

Title: Some features of a modern overhead distributing system
Creator: Redman, A. R.
Date: 2009, 1916
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/somefeaturesofmo00redm
Thesis (B.S.)--Armour Institute of Technology

Title: Track Elevation
Creator: Badger, Le Roy, Walbridge, John T.
Date: 2009, 1907
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/trackelevation00badg
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 34-36

Title: Zinc nitride, its formation, properties and alloys
Creator: Savoye, W. J., Edwards, A. R.
Date: 2009, 1921
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/zincnitrideitsfo00savo
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 25-28

Title: Relationship of Executive Fuction Patterns and Academic Achievement Across DSM-IV Subtypes of Attention-Deficit/Hyperactivity Disorder
Creator: Young, Crystal
Date: 2012-07-18, 2012-07
Description: The aim of this study was to expand our understanding of the impact of executive function skills on academic achievement in children with ADHD...
Show moreThe aim of this study was to expand our understanding of the impact of executive function skills on academic achievement in children with ADHD, as well as investigate trends in executive functioning and academic achievement between ADHD subtypes in an adolescent sample. Each participant completed neuropsychological assessments including a measure of intelligence and academic functioning as well as several measures of executive functioning. Results suggested that children with ADHD – Combined Type do not significantly differ from children with ADHD – Inattentive Type on tasks of academic or executive functioning. Issues regarding outcomes associated with ADHD as well as diagnostic procedures are discussed.
Ph.D. in Psychology, July 2012
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Title: INVOLVEMENT OF MIR-182 IN THE ACTION OF ATORVASTATIN IN PROSTATE CANCER CELLS
Creator: Li, Wenping
Date: 2013-04-10, 2013-05
Description: Atorvastatin (ATO), a widely used statin for lowering cholesterol was examined for its chemopreventive/therapeutic activities in prostate...
Show moreAtorvastatin (ATO), a widely used statin for lowering cholesterol was examined for its chemopreventive/therapeutic activities in prostate cancer cells. We found that ATO inhibited cell proliferation and induced autophagy in PC3 prostate cancer cells, as marked by significant induction of an autophagy marker LC3-II. Using Taqman RT-PCR technique, we also found that ATO treatment for 24h and 48h consistently up-regulated miR-182 in PC3 cells. However, adding geranylgeraniol (GGOH) to the culture media reversed the effect of ATO in regulating miR-182, suggesting that ATO up-regulates miR-182 through inhibition of geranylgeranyl biosynthesis. Overexpression of miR-182 in PC3 cells significantly decreased cell proliferation by about 36% (MTT assay), while knock-down of miR-182 stimulated cell proliferation by about 43% (MTT assay). In screening for miR-182 target genes, we found that Bcl2 and p21 are potential miR-182 target genes; Bcl2 was significantly down-regulated by ATO at both mRNA and protein levels and miR-182 knock-down up-regulated Bcl2 protein; p21 protein expression was positively correlated with alteration of miR-182 expression levels in PC3 cells. Through screening database of miR-182 target genes from TargetScanHuman 6.2 and PicTar, we found that p21 is not the direct target gene of miR-182, so it could be regulated by miR-182 indirectly. It has recently been established that miR-182 regulation is p53-dependent, since PC3 cells are p53 negative, it is clear that ATO regulates miR-182 in a p53-independent manner. These data demonstrate that miR-182 up-regulation and Bcl2 down-regulation by ATO could be two independent events and both could be involved in ATO mediated cell proliferation and autophagy.
M.S. in Biology, May 2013
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Title: Study of automatic electric fire pumps
Creator: Ross, L. R., Ballard, L. E., Swearingen, R.e.
Date: 2009, 1906
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofautomatic00ross
Thesis (B.S.)--Armour Institute of Technology

Title: A test of a commutating rectifier
Creator: Watt, William T., Stryker, Clinton E.
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/testofcommutatin00watt
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 75

Title: A study of the effects produced on Portland cement by the addition of various percentages of hydrated lime
Creator: Knuepfer, Claude Albert, Hook, Leonard Doolittle
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofeffectspr00knue
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 99

Title: The thermal conductivity of various forms of tile and their value as fireproofing materials
Creator: Anderson, S. W., Chamberlin, J. F.
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/thermalconductiv00ande
Thesis (B.S.)--Armour Institute of Technology

Title: The study of an air washer
Creator: Armspach, Otto W., Haines, E. Wilfred
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofairwasher00arms
Thesis (B.S.)--Armour Institute of Technology

Title: DOES NUTRITION KNOWLEDGE MODERATE THE ASSOCIATION BETWEEN PERFECTIONISM AND EATING DISORDER SYMPTOMATOLOGY?
Creator: Schwartz, Natalie
Date: 2017, 2017-05
Description: The trait of perfectionism is a psychological factor linked with the development of disordered eating, though the relation is unclear with...
Show moreThe trait of perfectionism is a psychological factor linked with the development of disordered eating, though the relation is unclear with some studies pointing to perfectionism as a predictor of eating disorder symptoms, while other studies have failed to find a statistically significant association. These discrepant findings suggest a need for understanding other factors that could be impacting the association. Research has suggested that individuals with eating disorders perform better than controls on knowledge of sources of nutrients and that while individuals with eating disorders spend more time reading about nutrition, this knowledge tends to be selective and skewed towards the aspects that maintain the eating disorder. The current study aimed to investigate the role of nutrition knowledge as a factor that may significantly influence the association between perfectionism and disordered eating attitudes. College women (N=122) completed several questionnaires related to disordered eating, nutrition knowledge, and perfectionism. The main research questions were: 1) whether perfectionism was related to disordered eating attitudes, 2) whether nutrition knowledge was related to disordered eating attitudes, and 3) whether nutrition knowledge moderated the relation between perfectionism and disordered eating attitudes. Results supported a positive association between perfectionism and disordered eating attitudes, in line with previous research. Despite a non-significant association between nutrition knowledge and disordered eating attitudes, there was found to be trend level significance (p<.07) for one moderation model. Specifically, the model assessing overall body dissatisfaction accounted for 33.34% of the variance, with a significant main effect for the level of perfectionism,suggesting the greater the degree of perfectionism traits, the greater the level of body dissatisfaction. While more research is needed to further develop an understanding of the link between perfectionism and disordered eating, nutrition knowledge is one possible avenue to explore in order to develop more effective prevention and intervention efforts.
M.S. in Psychology, May 2017
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Title: Transmission efficiencies of belting
Creator: Marks, Robert Edward
Date: 2009, 1919
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/transmissioneffi00mark
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 29

Title: Wagner single phase induction motor
Creator: Ash, H. J., Croskey, Philip
Date: 2009, 1905
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/wagnersinglephas00ashh
Thesis (B.S.)--Armour Institute of Technology

Title: SITE-DIRECTED MUTAGENESIS STUDY OF VITREOSCILLA HEMOGLOBIN-THE ROLE OF TYROSINE (B10) AND PROLINE (E8) IN THE STRUCTURE OF THE LIGAND-BINDING SITE
Creator: Zhang, Yifan
Date: 2015, 2015-05
Description: Vitreoscilla is a genus of Gram-negative aerobic bacterium which has the capability to synthesis a soluble, homodimertic hemoglobin,...
Show moreVitreoscilla is a genus of Gram-negative aerobic bacterium which has the capability to synthesis a soluble, homodimertic hemoglobin, Vitreoscilla hemoglobin (VHb). The Vitreoscilla hemoglobin was the first bacterial hemoglobin discovered, and has a wide range of biological and biotechnological applications. The distal site is one of the hot spots in VHb studies because of its unique structure. The Tyrosine residue at B10 and its hydrogen bonded Proline at E8 were considered as the ligand binding functional sites in distal space of VHb according to the previous study. In this study, two single mutated and one double mutated Vitreoscilla hemoglobin at position B10 and E8 were constructed and purified. In the two single mutants, the Tyr at B10 and the Pro at E8 were mutated to Ala. In the double mutant, both of the sites were mutated to Ala. The CO di↵erence spectrum data of the mutants indicate that the ligand binding ability of the Vitreoscilla hemoglobin was not neutralized by the mutations at ProE8 and TyrB10. Circular dichroism spectrum data of the mutants is similar to the wild type Vitreoscilla hemoglobin, which means the globin secondary structure is conserved. However the micro-environment in the distal sites is changed: the IR spectrum of the carbonyl stretch bond red-shifted in the CO bound VHb double mutant. A molecular dynamic simulation was introduced in the study to o↵er some guidance for future research plans. The simulation results showed that the B10 and E8 residue mutated to Ala might reduce the flexibility of the D-region, because of the more completed C and E helix. The volume of cavity where the heme group inserts changes significantly in various mutant models, which may provide a rough explanation of the change in carbonyl stretch bond IR spectrum. Additionally, an interesting conformation of Gln E7 was found in the simulation of double mutant model.
M.S. in Biology, May 2015
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Title: Tests on the gravity cell
Creator: Evans, P. W., Linderberg, W. A.
Date: 2009, 1912
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/testsongravityce00evan
Thesis (B.S.)--Armour Institute of Technology

Title: ECONOMIC BASED CONTROL SYSTEM DESIGN
Creator: Omell, Benjamin Peter
Date: 2013, 2013-12
Description: EMPC differs from traditional MPC by directly utilizing a profit based function as the objective as opposed to a quadratic function that...
Show moreEMPC differs from traditional MPC by directly utilizing a profit based function as the objective as opposed to a quadratic function that minimizes the distance from a set point that is predetermined. However, implementation of EMPC can result in unexpected and at times pathological closed-loop behavior, including inventory creep, bang-bang actuation and instability. To address these issues, an infinite-horizon version of EMPC is developed and shown to avoid many of the performance issues observed in the finite-horizon version. First, modifications to the EMPC problem will be used for the conceptual development of the Economic Linear Optimal Controller (ELOC), which is a statistically constrained linear feedback controller. Then, pointwise- in-time constraints can be reintroduced using one of two methods; Constrained ELOC or Infinite-Horizon EMPC (IH-EMPC). We also investigate the impact of problem formulation modifications on the ELOC. The first issue is that of disturbance modeling and the second is the impact of controller sample-time. The third topic concerns incorporation of computational delay in the feedback-loop, using both full and partial state information structures. Finally an illustration of the impact of plant-model mismatch is presented. The Constrained ELOC formulation is further modified to allow for market responsive smart grid applications. In particular an Integrated Gasification Combined Cycle (IGCC) process with hydrogen storage will be used to demonstrate the Constrained ELOC for such applications. The ELOC will be used as a vehicle to exploit dispatch capabilities by pursuing directly the objective of maximizing revenue. The idea being that process modifications to enable dispatch capabilities will allow for a time-shift of power production away from periods of low energy value to periods of high value. An in depth discussion is provided on how energy value forecasts are incorporated into the design of the constrained ELOC. Finally, an extension of the ix ELOC to the controller embedded equipment design is provided. The work concludes with a discussion of the computational aspects of solving the ELOC problem. In particular, the impact of reverse-convex constraints inherent to the ELOC problem are discussed along with existing solution methods. The main contribution of this final chapter is a novel application of the Generalized Bender’s Decomposition (GBD) algorithm to the ELOC problem. This new approach is shown to retain global optimality, reduce computational effort (by orders of magnitude) and expand the class of problems one can solve.
PH.D in Chemical Engineering, December 2013
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