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Title: Investigation of the properties of chilled cast iron as a material for permanent magnets
Creator: Harrington, Philip, Smith, G. W.
Date: 2009, 1906
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/investigationofp00smit
Thesis (B.S.)--Armour Institute of Technology

Title: ENSURING SECURITY AND PRIVACY IN BIG DATA SHARING, TRADING, AND COMPUTING
Creator: Jung, Taheo
Date: 2017, 2017-05
Description: We have witnessed huge values of the big data in the last decade, and it is evidential that the data bring large added values to the business...
Show moreWe have witnessed huge values of the big data in the last decade, and it is evidential that the data bring large added values to the business in various areas. Owing to such opportunities, the data collection and archival became one of the most successful business strategies in the industry, and more and more user-generated data are now being acquired, stored, provisioned, and consumed nowadays. Increased collection made human being more closely involved in the life cycle of the big data characterized by the acquisition, storage, provisioning, and consumption, and larger security and privacy challenges emerged. People’s awareness of such threats led to various efforts by the governments, industry, and academia, and our efforts described in this dissertation also belong to them. We have investigated the security and privacy challenges emerging in various parts of the life cycle big data experience nowadays, and I present our major discoveries in this dissertation which are composed of three major parts: (1) security and privacy in storage of big data; (2) theoretic foundations of privacy-preserving data computing; (3) security in big data trading. We addressed new or existing security/privacy threats existing in different parts of the big data life cycle by either leveraging existing works in intelligent ways or by proposing our novel technologies. The contributions of our discoveries cam be summarized as the protection of user privacy and data security while supporting the original functionalities at negligible extra computation/communication/storage overhead.
Ph.D. in Computer Science, May 2017
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Title: MODELING AND COMPUTATIONAL FLUID DYNAMICS SIMULATION OF A BUBBLING FLUIDIZED BED PROCESS AT DIFFERENT SCALES
Creator: Jang, Jungkee
Date: 2012-11-14, 2012-12
Description: In recent years there has been increased research activity in the experimental and numerical study of gas-solid flow system in the bubbling...
Show moreIn recent years there has been increased research activity in the experimental and numerical study of gas-solid flow system in the bubbling fluidized bed process. The bubbling fluidized bed process have numerous applications in the energy, pharmaceuticals, and chemicals process industries since it has provides a number of advantages such as large heat capacity inside a bed, and rapid heat and mass transfer rate. A reliable design and scale-up approach for a bubbling fluidized bed process requires a very detailed model based on the fundamentals of multiphase transport phenomena. The present works address the simulation and scale-up of rather complex gas-solid flow behavior in bubbling beds using Computational Fluid Dynamics (CFD) approach. The CFD model developed in this study which is based on two fluid model was used to optimize the performance and utilized as a scale-up tool for an isothermal and a non-isothermal bubbling fluidized bed process. For isothermal case, 2-Dimensional and 3-Dimensional simulations of bubbling beds for both PSRI laboratory and large scales fluidized beds using a kinetic theory approach were performed. The FLUENT code was used to conduct the simulations. Our simulation results were validated and refined by comparing them with the laboratory-scale experimental data of PSRI. Then, our modified 2-D and 3-D CFD models were used to predict the large-scale PSRI bubbling fluidized bed performance at different operating conditions. In our 3-D simulations, we used exactly the same bed dimensions and inlet configurations (such as air distributor) as the experimental one to predict the characteristics of gas-solid flow patterns in the PSRI large-scale bubbling fluidized bed. The numerical simulation results compared well with both PSRI large scale experimental xx data on pressure drop and time-averaged void fraction near the wall, which could be a very good proof for demonstrating the capability of CFD as a tool to be used in the design and scale-up of bubbling fluidized bed systems. For non-isothermal case, the set of equations necessary to describe the flow patterns and heat/mass transfer phenomena of bubbling beds at three different scales were developed. CFD simulations were performed to investigate the characteristics of pharmaceutical particle drying process in bubbling fluidized beds at three different scales (e.g., lab, kilo, and 10-kilo scales). The results of CFD simulation were compared with the experimental data obtained at laboratory-scale (Duquesne University experiments), to validate and refine our CFD model. The modified model was used to simulate the drying of the same material in Abbott laboratory kilo and 10-kilo scale units. Our simulation results for solid particles drying as a function of dimensionless time showed that our CFD model along with similar dimensionless group similarity approach can be used as a tool to scale-up the drying process from experimental scale to both kilo-scale and 10-kilo scale fluidized bed dryer. Moreover, to determine the optimum particle mixing, numerical simulations were performed at different particle diameters, bed heights, inlet velocities and inlet velocity distributions, respectively. The numerical simulation results compared well with the experimental data (performed by Duquesne University and Abbott laboratory) on moisture removal rate and outlet gas temperature. This also could be a very good proof for demonstrating the capability of CFD as a tool to be used in the design and scale-up of non-isothermal bubbling fluidized bed processes.
PH.D in Chemical Engineering, December 2012
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Title: DYNAMICS OF VESICLES IN VISCOUS FLUID
Creator: Liu, Kai
Date: 2014, 2014-12
Description: Modeling vesicle dynamics involves a complicated moving boundary problem where uids, thermal uctuations, and vesicle morphology are intimately...
Show moreModeling vesicle dynamics involves a complicated moving boundary problem where uids, thermal uctuations, and vesicle morphology are intimately coupled. In this thesis, we study the dynamics of a two-dimensional membrane in linear viscous ows. In the asymptotic analysis section, we derive deterministic and stochastic equations describing the motion of a slightly perturbed membrane interface. Using a 2nd order Runge-Kutta method, we solve these equations numerically, and explain the formation and development of wrinkling patterns. We then develop a boundary integral method and an immersed boundary method for simulating the nonlinear wrinkling dynamics of a homogenous vesicle in viscous ows. The nonlinear results agree with the asymptotic theory for a nearly circular vesicle, and also agree with experimental results for an elongated vesicle. Using a stochastic immersed boundary method, we investigate the e ects of thermal uctuations in vesicle dynamics. Comparing with the deterministic results, thermal uctuation can lead to the development of odd modes and asymmetric wrinkles. Finally, we investigate the nonlinear wrinkling dynamics of a multi-component vesicle. The model includes a 4th order Cahn-Hilliard type equation describing the phase transitions on the vesicle surface. We nd that for an elongated vesicle with large excess arc length, the inhomogeneous bending introduces nontrivial asymmetric wrinkling and buckling dynamics.
Ph.D. in Applied Mathematics, December 2014
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Title: VANADIUM OXIDE BASED MATERIALS AS OXIDATIVE DEHYDROGENATION CATALYST: SYNTHESIS, CHARACTERIZATION AND PROPERTIES
Creator: Aydemir, Kadir
Date: 2013, 2013-12
Description: The project concerns with design, synthesis and characterization of molecular and extended structure materials composed of vanadium oxides and...
Show moreThe project concerns with design, synthesis and characterization of molecular and extended structure materials composed of vanadium oxides and evaluation of their catalytic oxidative dehydrogenation (ODH) properties. A long-term objective is to develop an understanding of the structure-property relationships in ODH catalysts. Chapter 1 provides an overview of the field of metal oxides, polyoxometalates, and catalytic oxidative dehydrogenation of propane. This chapter also defines the research problem concerning this thesis and its fundamental and practical significance. Chapters 2-4 describe the synthesis, characterization and ODH properties of a select number of structurally correlated vanadium oxide based materials. The ODH catalysts studied in this work includes molecular compounds - (NH4)8[VIV 12VV 6O42(SO4)0.85(VO4)0.15]·10H2O (NH4-POV) and NH4V10O28, layered structure materials - MgVV 2VIV 2O10·4H2O (MV4) and V2O5, a chain structure - NH4VO3, and a nanostructured three-dimensional framework material - [Co3V18O42(H2O)12 (XO4)]·24H2O (X = V, S) (Co-POV). Their catalytic activities for ODH of propane to propylene - an important industrial feedstock material, were studies and compared in an attempt to get an insight of the structure-property relationships. Chapter 2 discusses synthesis and characterization of a new mixed-valence vanadate, MgVV 2VIV 2O10·4H2O (MV4), an extended structure solid, synthesized hydrothermally and characterized by single-crystal X-ray diffraction, spectroscopic methods, thermogravimetric analyses and temperature dependent magnetic measurements. MV4 represents the first model compound for the naturally occurring mineral melonovanadite, Ca2VV 4VIV 4O20·10H2O. MV4 is an important material with xv structural and electronic properties that are attractive for making it a potential promising ODH catalyst. The framework structure in MV4 consists of vanadium oxide layers crosslinked by {Mg(H2O)4} groups. The vanadium oxide layers are composed of edge shared {VIVO5} square pyramids, forming {V2O8} dimers, which share corners with {VVO4} tetrahedral units. Chapter 2 also discusses synthesis of a novel mixed-valence molecular polyoxovanadate - (NH4)8[VIV 12VV 6O42(SO4)0.85(VO4)0.15]·10H2O (NH4-POV) and its characterization by single-crystal X-ray diffraction, spectroscopic and thermogravimetric analyses. Structure consists of {V18O42} shell composed of 18 edge sharing {VO5} square pyramids, hosting a tetrahedral species {XO4} (X = S, V). Highly reduced molecular structure of NH4-POV makes it a promising ODH catalyst. Chapter 3 describes the ODH properties of a polyoxovanadate based openframework material - [Co3V18O42(H2O)12 (XO4)]·24H2O (X = V, S) (Co-POV). It is composed of {V18O42(XO4)} (X = S, V) building units, which is the molecular cluster present in NH4-POV, interconnected by {-O-Co-O-} bridging groups. Alternatively, since the building unit clusters {V18O42XO4} can be viewed as derived from sheets of V2O5, the 3-D structure of Co-POV can be viewed as made of V2O5 and CoO units. Therefore the ODH property of Co-POV was compared with the ODH property of the molecular cluster NH4-POV on one hand and with the V2O5 and CoO on the other hand. Co-POV was shown to have superior catalytic performance for ODH of propane as compared with its constituent metal oxides, V2O5, CoO and their mixture. ODH of propane reaction over NH4-POV catalyst has higher propylene selectivity of above 60% at moderate temperatures as compared to 37% selectivity of Co-POV catalyst. Supporting NH4-POV on high surface area γ-alumina was shown to improve propane xvi conversion drastically. In this study, highest propylene yield of 13% was achieved at 550 °C by supported NH4-POV catalyst. On the other hand, MV4 showed catalytic activity at marginally low temperature 200 °C due to propane activation energy (Ea) of 27 kJ/mol, the lowest Ea found in this study. Co-POV was utilized as a model compound to describe the effect of varying doses of γ-ray irradiation on the catalytic ODH properties of polyoxometalates for the first time. γ-ray irradiation enhanced catalysts’ selectivity to propylene during the oxidative dehydrogenation of propane. Chapter 4 describes full characterization of the catalysts studied in this work by powder X-ray diffraction analysis, temperature programmed reduction, X-ray absorption fine structure, BET surface area analysis and scanning electron microscopy. Structural changes of catalysts were investigated by comparing characterization results of asprepared, oxygen pretreated and post-catalysis (spent) catalysts. New vanadium oxide phases formed upon oxygen pretreatment. In general, ODH catalysis did not further alter catalysts’ structures.
PH.D in Chemistry, December 2012
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Title: LATTICE DESIGN OF THE INTEGRABLE OPTICS TEST ACCELERATOR AND OPTICAL STOCHASTIC COOLING EXPERIMENT AT FERMILAB
Creator: Kafka, Gene
Date: 2015, 2015-05
Description: The Integrable Optics Test Accelerator (IOTA) storage ring at Fermilab will serve as the backbone for a broad spectrum of Advanced Accelerator...
Show moreThe Integrable Optics Test Accelerator (IOTA) storage ring at Fermilab will serve as the backbone for a broad spectrum of Advanced Accelerator R&D (AARD) experiments, and as such, must be designed with significant flexibility in mind, but without compromising cost efficiency. The nonlinear experiments at IOTA will include: achievement of a large nonlinear tune shift/spread without degradation of dynamic aperture; suppression of strong lattice resonances; study of stability of nonlinear systems to perturbations; and studies of di↵erent variants of nonlinear magnet design. The ring optics control has challenging requirements that reach or exceed the present state of the art. The development of a complete self-consistent design of the IOTA ring optics, meeting the demands of all planned AARD experiments, is presented. Of particular interest are the precise control for nonlinear integrable optics experiments and the transverse-to-longitudinal coupling and phase stability for the Optical Stochastic Cooling Experiment (OSC). Since the beam time-of-flight must be tightly controlled in the OSC section, studies of second order corrections in this section are presented.
Ph.D. in Physics, May 2015
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Title: AN ENERGY-PRESERVING SCHEME FOR THE POISSON-NERNST-PLANCK EQUATIONS
Creator: Kabre, Julienne
Date: 2017, 2017-07
Description: Transport of ionic particles is ubiquitous in all biology. The Poisson-Nernst- Planck (PNP) equations have recently been used to describe the...
Show moreTransport of ionic particles is ubiquitous in all biology. The Poisson-Nernst- Planck (PNP) equations have recently been used to describe the dynamics of ion transport through biological ion channels (besides being widely employed in semiconductor industry). This dissertation is about the design of a numerical scheme to solve the PNP equations that preserves exactly (up to roundoff error) a discretized form of the energy dynamics of the system. The proposed finite difference scheme is of second-order accurate in both space and time. Comparisons are made between this energy dynamics preserving scheme and a standard finite difference scheme, showing a difference in satisfying the energy law. Numerical results are presented for validating the orders of convergence in both time and space of the new scheme for the PNP system. The energy preserving scheme presented here is one dimensional in space. A highlight of an extension to the multi-dimensional case is shown.
Ph.D. in Applied Mathematics, July 2017
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Title: UNDERSTANDING VACCINATION ATTITUDES AND DETECTING SENTIMENT STIMULUS IN ONLINE SOCIAL MEDIA
Creator: Kadam, Mayuri
Date: 2017, 2017-05
Description: Vaccination being one of the most important decisions for public health, has become a debatable topic with the rise in anti-vaccination...
Show moreVaccination being one of the most important decisions for public health, has become a debatable topic with the rise in anti-vaccination sentiments in recent years. Knowing that vaccines have eradicated many endemic diseases, the rise in antivaccination sentiments jeopardizes the human health by altering the vaccine decisions. Rapidly changing information sources with the increased reach of online social media provide users with a huge amount of information and misinformation. Users exposed to these media perceive the provided information and hold an attitude towards it. Being an open platform of discussions and opinion expressions, online social media provides a great source for understanding people’s behavior. We use supervised learning for understanding the flow of vaccine sentiments and analyzing the user attitudes through online social media. In this thesis, we determine the events and incidences responsible for amplifying pro-vaccination and anti-vaccination sentiments. We investigate user behaviors and important topics of interest for these users. We develop a model for predicting a new user’s attitude utilizing that user’s recent Twitter activity.
M.S. in Computer Science, May 2017
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Title: INVESTIGATION OF PERFORMANCE AND DURABILITY OF POLYMER ELECTROLYTES FOR ELECTROCHEMICAL ENERGY STORAGE AND CONVERSION TECHNOLOGIES
Creator: Jung, Min-suk
Date: 2016, 2016-07
Description: Polymeric ion exchange membranes are integral components of electrochemical conversion/storage devices such as fuel cells, water electrolyzers...
Show morePolymeric ion exchange membranes are integral components of electrochemical conversion/storage devices such as fuel cells, water electrolyzers, and redox flow batteries. There has been dramatic progress in the research and development of cation exchange membranes (CEM). Nafion® (perfluorosulfonic acid membranes) is one example of a state-of-the-art CEM and has been successfully demonstrated in various electrochemical energy devices. Unlike CEMs, anion exchange membranes (AEMs) have been of limited utility to date due to their drawbacks, including poor chemical/mechanical stability and low ionic conductivity. However, alkaline environments result in better activity for electrochemical reactions and afford the possibility of using non-platinum group metal (PGM) electrocatalysts. AEMs, therefore, are still being studied in order to resolve existing challenges in terms of conductivity and stability in alkaline media and in strongly oxidizing solutions. In this work, AEMs derived from different types of polymer backbones were prepared, and their chemical stability and electrochemical property were investigated. Polysulfone (PSF) AEMs were prepared by first chloromethylating polysulfone, then by functionalizing chloromethylated polysulfone (CMPSF) with different base reagents. PSF-trimethylamine (TMA) AEMs showed a 40-fold reduction in vanadium (IV) ion (VO2+) permeability when compared to a Nafion® membrane and exceptional oxidative stability after exposure to a 1.5 M vanadium (V) ion (VO2 +) solution for 90 days. PSF-TMA AEMs were successfully demonstrated in the all-vanadium redox flow battery. Excellent energy efficiencies (>75 %) were attained and sustained over 75 chargedischarge cycles for a vanadium redox flow battery prepared using the PSF-TMA separator. Crosslinking of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) AEMs using diamine was tried with intentions to improve the mechanical stability and electrochemical property of PPO AEM. Crosslinked PPO AEMs (30 ± 4 % at 25 oC) showed less liquid water uptake than non-crosslinked PPO AEMs (46 ± 5% at 25 oC) while maintaining comparable ionic conductivities (hydroxide ion conductivity of 45 mS/cm at 60 oC). Crosslinked PPO AEMs maintained mechanical integrity and still showed some mechanical stability (ultimate tensile strength of 3~4 MPa and elongation at break of 13~17 %) after exposure to 1 M KOH at 60 oC for 14 days, while noncrosslinked PPO AEMs completely lost their mechanical durability. Finally, this dissertation presents research related to perfluorinated AEMs prepared using a Grignard reagent. These membranes exhibited 0.7 mmol/g of Cl- ion exchange capacity (IEC), 20 mS/cm of hydroxide ion conductivity at 20 oC, and 10 % of water uptake at room temperature. The membranes also maintained 90 % of their initial conductivity after an exposure to 1.5 M VO2+ in 3 M H2SO4 solution for seven days.
Ph.D. in Chemical Engineering, July 2016
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Title: INVESTIGATION ON THE INTERACTION BETWEEN NATURAL ORGANIC MATTER AND CALCITE
Creator: Zhu, Junjie
Date: 2012-07-12, 2012-07
Description: Fox River water was supersaturated with respect to calcite; natural organic matter (NOM) might play a key role in this phenomenon. Fox River...
Show moreFox River water was supersaturated with respect to calcite; natural organic matter (NOM) might play a key role in this phenomenon. Fox River NOM (FRNOM) adsorption on the calcite surface is probably an important mechanism to explain this condition. Fox River water contained moderate ultraviolet absorbance (UVA) of NOM (0.19 1/cm), high concentration of calcium (70 mg/L), suspended solids with relatively high specific surface area (SSA) (6.9 m2/g), and moderate pH value (8.4) based on historical data. To test whether the phenomenon was caused by NOM adsorption, a series of experiments was conducted to explore the interaction between NOM and calcite in conditions similar to those of the Fox River. Suwannee River NOM (SRNOM) and Nordic Reservoir NOM (NRNOM) were used as surrogate NOM. The results show that SRNOM inhibited calcite dissolution significantly after 10 min based on measuring of the decrease in the free calcium concentration. The decrease in the free calcium was not solely due to formation of NOM-calcium complexes, because these complexes made up only about 3% of the total free calcium concentration. Therefore, NOM adsorption onto calcite was probably largely responsible for the inhibited calcite activity. Experimental results also showed that NOM adsorption increased with increasing NOM concentration in the range from 2 to 14 mg NOM/L, which is a common range for river water. Higher charge density also seems to promote sorption onto calcite; relative to NRNOM, SRNOM has a higher charge density and SRNOM has a higher affinity for calcite. Other factors that promoted NOM adsorption onto calcite included higher concentration of calcium and larger SSA of calcite seed. Based on water quality characteristics, the Fox River provides a suitable environment for NOM adsorption on calcite, and it seems likely that Fox River NOM (FRNOM) adsorption on calcite can inhibit calcite precipitation. This understanding of interaction between NOM and calcite could be used by WTPs along the Fox River for better optimization and improvement in treatment and operation.
M.S. in Environmental Engineering, July 2012
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Title: MEASUREMENT MODEL OF IONOSPHERIC ELECTRON CONTENT WITH CYGNSS
Creator: Zhang, Jordi Xing
Date: 2013, 2013-12
Description: Global ionospheric imaging is currently limited by a lack of significant quantities of observations over the oceans. This deficiency of...
Show moreGlobal ionospheric imaging is currently limited by a lack of significant quantities of observations over the oceans. This deficiency of measurements arises because coverage from Global Navigation Satellite System (GNSS) remote sensing tools is typically limited to regions over land by using ground-based receivers. This dissertation presents the opportunity to estimate ionospheric data over the oceans by using reflected GNSS signals received by the upcoming Low-Earth Orbit (LEO) satellite constellation Cyclone Global Navigation Satellite System (CYGNSS). CYGNSS is currently being developed by NASA primarily for hurricane predictions. Its eight micro-satellites will have a single-frequency Global Positioning System (GPS) receiver onboard and zenith and nadir antennas that collect GPS signals reflecting from the ocean surface of Earth. This study investigates the possibility of leveraging CYGNSS for a secondary science mission, using GNSS-Reflectometry for ionospheric remote sensing. A mathematical model is developed that retrieves ionospheric electron content by using ranging measurements from direct and ocean-reflected GPS signals onboard CYGNSS satellites. The measurement model terms can be grouped as geometric raypath and signal refraction components due to the troposphere and the ionosphere. Each term of the model is analyzed and quantified by applying fundamental physical principles and empirical models. The implementation of a multi-orbit simulation estimates the magnitudes of anticipated electron content measurements with CYGNSS.
M.S. in Mechanical and Aerospace Engineering, December 2013
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Title: DEVELOPING INTELLIGENT AND ADAPTIVE BUILDING SYSTEMS FOR OUR DIGITAL ECOLOGY
Creator: Hansen, Kai
Date: 2013, 2013-07
Description: Our world is being changed by a dynamic digital presence. The marriage of virtual and physical represents an ecology which has become...
Show moreOur world is being changed by a dynamic digital presence. The marriage of virtual and physical represents an ecology which has become intertwined with the lives of nearly everyone, fundamentally altering how our society functions. While we have evolved in this sense, the built environment has become outmoded and strains to meet emerging occupant requirements. To correct this, it has become necessary to develop environments that are capable of intelligently responding to shifting requirements. As curators of the built environment, architects are responsible for seeking out and engaging new mechanisms to achieve spaces that occupants find desirable. An experiential summary of the architectural-digital-hacking process will be given. A more traditional research method was followed when possible while engaged in this learning process. This research focuses on utilizing readily available digital tools that are capable of simultaneously mitigating issues associated with occupant requirements and energy consumption. It will also address shortcomings related to occupant comfort and energy consumption observed in our buildings by producing a series of working prototypes that will be tested and analyzed. Results will be presented, and will consist of components used and how they were used to serve as a reference for future development.
M.S. in Architecture, July 2013
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Title: Behavior of E. Coli 0157:H7 in Packaged Spinach after Exposure to Sanitizing Solution
Creator: Lu, Yin
Date: 2011-12-13, 2011-12
Description: Leafy greens have been associated with multiple outbreaks of Escherichia coli O157:H7 (EC) infection in recent years. More information is...
Show moreLeafy greens have been associated with multiple outbreaks of Escherichia coli O157:H7 (EC) infection in recent years. More information is needed on EC survival during post-harvest processes, and our study aimed at evaluating survival in packaged spinach after treatment of cells with sodium hypochlorite. A green fluorescent protein-expressing strain of EC was exposed to sodium hypochlorite in two different ways, i.e., exposed in solution or on the spinach leaves. For exposure in the solution, EC was inoculated into 1 ppm sodium hypochlorite for 30 seconds, then the cells were inoculated onto the spinach leaves. For exposure on the spinach leaves, EC was first inoculated onto leaves; then the inoculated spinach leaves were dipped into 100 ppm sodium hypochlorite. After inoculation, the spinach was packaged to obtain high-oxygen (20%O2/3%CO2) and low-oxygen (0%O2/15%CO2) atmospheres, respectively. The packages were stored at 4°C or 15°C, and EC populations were quantified at six sampling points during 14 days of storage. The data were analyzed by DMFit and Microfit to demonstrate the growth curve and kinetics. In general, there were no apparent differences in EC behavior between the chlorine treated and control groups for most of the conditions. However, in certain conditions, the chlorine-treated cells showed a faster decrease and/or slower increase in population than the control packages. Generally, low temperature and high oxygen conditions led to lower survival than high temperature and low oxygen. For EC exposed in solution, the EC population showed a greater reduction and faster decrease in the high-oxygen than low-oxygen packages at 4°C. At 15°C, the lowoxygen condition resulted in a faster growth rate (+0.43 log CFU/ml/day) than high oxygen packages (+0.17 log CFU/ml/day). Also, in the 4°C high-oxygen condition, the chlorine-treated cells showed a greater population decrease (-0.95 log CFU/ml) than the control groups (-0.57 log CFU/ml). For EC exposed on the spinach, the low-oxygen packages showed greater population levels and faster growth rates compared to the highoxygen packages at 15°C. At 4°C, chlorine treated groups and control groups showed no apparent differences for both low- and high- oxygen packages. At 15°C, the chlorine treated packages showed less increase in population (+0.79 log CFU/ml) than the controls (+1.58 log CFU/ml) in low-oxygen; and the control groups increased at a faster growth rate (+0.57 log CFU/ml/day) than the chlorine treated ones (+0.25 log CFU/ml/day).
M.S. in Food Safety and Technology, December 2011
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Title: LOAD ANALYSIS BASED ON MACHINE LEARNING IN POWER SYSTEMS
Creator: Lu, Dan
Date: 2017, 2017-05
Description: The dissertation is composed by four parts, first, load sampling for SCUC based on Principal Component Analysis (PCA) and Kernel Density...
Show moreThe dissertation is composed by four parts, first, load sampling for SCUC based on Principal Component Analysis (PCA) and Kernel Density Estimation (KDE); second, load forecasting based on PCA and Bayesian ridge regression; third, anomalies detection based on Machine Learning methodology; fourth the long-term planning of Battery-based Energy Storage Transportation (BEST) in power system. Mathematical models are constructed to fulfill the research of the three targets, and numerical examples are used to test the models. The first three parts are based on PCA, which reduced the load dimensions. In the first part, a robust power system Unit Commitment (UC) is the aim to fulfil the possible load. In the second part, a novel short-term nodal load forecasting is raised to give better prediction of the next day load to improve the next data UC scheduling. In the third part, anomalies are detected in the reduced power flow space based on the pattern identified in the lower dimensional space. The purpose of the fourth part is to find ways of better utilizing the existing resources from integrating the frontier technology, the mobility of more compact and higher capacity batteries. Mix-integer programming (MIP) is used in the formulation.
Ph.D. in Electrical Engineering, May 2017
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Title: THE TEMPORAL RELATIONSHIP BETWEEN DEPRESSION AND THE CONVERSION TO DEMENTIA: A RETROSPECTIVE ANALYSIS
Creator: Rog, Lauren
Date: 2011-07, 2011-07
Description: A relationship between depression and the dementing process has been fairly well established in both patients with mild cognitive impairment ...
Show moreA relationship between depression and the dementing process has been fairly well established in both patients with mild cognitive impairment (MCI) and dementia (e.g., Apostolova and Cummings, 2008; Lyketsos et al., 2002; Starkstein et al., 2005). However, less clear is the temporal role depression plays in the dementing process, with the possibilities including depression as a risk factor, a prodrome, or a consequence of dementia. Variables that have been considered to affect this relationship include gender, depression severity, lifetime history of depression, and etiology of cognitive decline. The current study examined the temporal relationship between depression and dementia in a sample of 218 patients with MCI or dementia who were seen for at least one follow-up visit at the neuropsychology service of an urban university medical center. Results did not reveal support for either the prodrome or the risk factor hypothesis of the depression-dementia relationship. However, it was found that people with a past history of depression who did not show depressive symptoms concurrent with their cognitive decline converted most quickly to dementia, suggesting a unique depression-dementia relationship in people with earlier-life depression.
Ph.D. in Clinical Psychology, July 2011
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Title: MECHANICAL PROPERTIES AND MICROSTRUCTURE OF HEAT AFFECTED ZONE IN HPS 100W STEEL
Creator: Lu, Junhua
Date: 2011-11-21, 2011-12
Description: In the present investigation, thermal simulated specimens were used to investigate the effect of peak temperature during welding on...
Show moreIn the present investigation, thermal simulated specimens were used to investigate the effect of peak temperature during welding on characteristic fracture toughness and microstructural features of the heat-affected zones (HAZ) of HPS 100W Steel. HPS 100W is a new grade of bridge steel included in ASTM A709 Standard. The material was subjected to varying thermal profiles to simulate the different subzones of HAZ and the resultant microstructures were observed and mechanical properties determined. HAZ simulation was carried out in a Gleeble 3500 at different peak temperatures of 850oC, 1100oC and 1300oC with heat inputs of 3kJ/mm along with specimens transverse or longitudinal to the rolling direction. Subsequently, impact toughness data were obtained at different temperatures by means of a Charpy test. Finally, the different microstructures were characterized using optical microscopy, SEM and TEM in order to correlate the structure-property relationship of the HAZ for HPS 100W steel. Due to small heat-input and accelerated cooling, the grain size in HAZ is relatively small and the structures are ductile. The Charpy impact results show the transverse rolling direction toughness for lower peak temperature and base material have lower values than that of longitudinal direction samples. Nevertheless even the lowest Charpy values obtained are well above minimum values required for structural application transportation. The HAZ showed higher absorbed impact energy in lower temperature. Also, precipitation dissolution study of NbC and Cu was carried out in the end. Cu element is the strengthening element. The NbC have grain refining effect at elevated temperature.
M.S. in Science and Engineering, December 2011
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Title: HOUSING PUBLIC TRANSPORTATION WITHIN A SOCIAL CONDENSER
Creator: Loman, Catherine
Date: 2016, 2016-12
Description: Throughout the United States and Canada the railroad, a system that was once the central method of transportation through the countries, has...
Show moreThroughout the United States and Canada the railroad, a system that was once the central method of transportation through the countries, has had a large downfall in the popularity and development after the introduction of the car into the city and the surrounding area. With the downfall of the train came the downfall of the use of the train station, a space that was once a local temple of the city has now become an economic center with no larger connection to the city. If a new high-speed rail system is to be introduced into North America then there is the need for a new method of looking at what the train station can be and how it can interact with the larger city around it. With an in-depth study of the city that the station is located in the local nature of the city will become prevalent and play a key role in the conceptual design of the station and how it can create a stronger social presence within the city and within the line.
M.S. in Architecture, December 2016
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Title: STATISTICAL LEARNING IN SOCIAL INTERACTIONS: ANTICIPATION OF CAREGIVER FEEDBACK TO COMMUNICATIVE BEHAVIOR IN PRELINGUISTIC INFANTS
Creator: Lossia, Amanda Kathryn
Date: 2014, 2014-05
Description: A growing body of literature has demonstrated that infants are able to detect patterns in structured external environmental stimuli through a...
Show moreA growing body of literature has demonstrated that infants are able to detect patterns in structured external environmental stimuli through a statistical learning mechanism. The present study examines whether statistical learning operates as a learning mechanism in social interactions as well. Prior research using an ABA experimental design demonstrated that infants modified their communicative behavior when the level of contingent caregiver feedback to infant gestures was altered (Miller & Lossia, 2013). These findings are extended in the present study by examining whether the infants developed modified expectations for caregiver feedback when the pattern of contingent feedback was altered, which might function as a possible mechanism for the changes seen in infant communicative behavior. Anticipatory looking to the caregiver was used as a measure of infants’ expectations for caregiver responsiveness. Results showed differences in anticipatory looking to the caregiver across periods. The pattern of anticipatory looking did not fully explain the changes seen in infant communicative behavior. However, the findings do suggest that infants detected the change in caregiver feedback and modified their expectations, providing support for the presence of a statistical learning mechanism in social interactions.
M.S. in Psychology, May 2014
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Title: INTERPRETATION OF ADAPTIVE REUSE ISSUES IN MULTIPLE SCALES, BUILDING, NEIGHBORHOOD, CITY
Creator: Loukas, Panagiota
Date: 2015, 2015-12
Description: The purpose of this study is to interpret the topic of adaptive reuse, focusing on the reuse of existing buildings and new structures inserted...
Show moreThe purpose of this study is to interpret the topic of adaptive reuse, focusing on the reuse of existing buildings and new structures inserted into them. The issues related with adaptive reuse are not a new field in architecture but is related to previous practices such as preservation and conservation. Focusing on the issue of adaptive reuse in order for existing structures to cover the new needs of an emerging society, giving a new use. Other disciplines, such as social and political are forming and guiding those decisions. The topic of what to keep and what to discard is global and various solutions has been given in the past years, focusing on monuments and landmarks conservation, preservation or practices of adaptation in the cities history. The research analysis in various scales, engaging the site to its surrounding, through neighborhood analysis and its urban context are important. Understanding the problem means focusing the research not only on the aspect of architecture agenda since there are political and social practices engaging with the transformation. It means focusing on the issue of adaptive reuse as an important cultural topic related with social, political and economic factors.
M.S. in Architecture, December 2015
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Title: STEREO-BASED DEPTH MAP PROCESSING: ESTIMATION AND REFINEMENT
Creator: Loghman, Maziar
Date: 2016, 2016-12
Description: During the past decade, research in 3D video has become a hot topic owing to advancements in both hardware and software. Amongst different...
Show moreDuring the past decade, research in 3D video has become a hot topic owing to advancements in both hardware and software. Amongst different methods proposed for representing 3D data, multi-view video plus depth (MVD) format has gained a lot of attention. Most of such 3D algorithms rely on a per-pixel depth representation of the scene called a depth map. Depth maps are very useful for rendering virtual views and have lead to advancements in 3D compression algorithms. Generating an accurate and dense depth map is one of the important prerequisite for many 3D video applications. In this thesis, we highlight the following major problems in MVD. * Depth map estimation * Depth map refinement * Depth map coding In order to generate an accurate depth map, we propose a method based on Census transform with adaptive window patterns and semi-global optimization. A modified cross-based cost aggregation technique is proposed which helps to calculate a more reliable depth map. In order to further enhance the quality of the generated depth map, a novel multi-resolution anisotropic diffusion based algorithm is presented. The proposed depth refinement algorithm computes a dense depth map in which the holes have been filled and the object boundaries are sharpened. The next part of the research is based on depth map coding. In depth map coding, a considerable amount of time is required to investigate the mode decision pro- cess for every block of depth pixels. However, in real-time purposes, we can partially skip the mode selection step. In this thesis, we propose a novel depth intra-coding scheme for 3D video coding based on HEVC standard. The core idea of the proposed method is motivated by the fact that depth maps have specific characteristics that distinguish them from those of color images. By analyzing the reference depth maps based on homogeneousness of different regions, for some particular blocks, the DMM full-RD search is skipped and the mode is selected based on the previous similar tree- blocks. By this means, the time complexity of the encoding process is significantly reduced.
Ph.D. in Electrical Engineering, December 2016
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