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Advanced Text Analytics and Machine Learning Approach for Document Classification
Get PDFText classification is used in information extraction and retrieval from a given text, and text classification has been considered as an important step to manage a vast number of records given in digital form that is far-reaching and expanding. This thesis addresses patent document classification problem into fifteen different categories or classes, where some classes overlap with other classes for practical reasons. For the development of the classification model using machine learning techniques, useful features have been extracted from the given documents. The features are used to classify patent document as well as to generate useful tag-words. The overall objective of this work is to systematize NASA’s patent management, by developing a set of automated tools that can assist NASA to manage and market its portfolio of intellectual properties (IP), and to enable easier discovery of relevant IP by users. We have identified an array of methods that can be applied such as k-Nearest Neighbors (kNN), two variations of the Support Vector Machine (SVM) algorithms, and two tree based classification algorithms: Random Forest and J48. The major research steps in this work consist of filtering techniques for variable selection, information gain and feature correlation analysis, and training and testing potential models using effective classifiers. Further, the obstacles associated with the imbalanced data were mitigated by adding synthetic data wherever appropriate, which resulted in a superior SVM classifier based model
Characterization of genes involved in phycobiliprotein biosynthesis in Fremyella diplosiphon and Thermosynechococcus elongatus
Get PDFCyanobacteria are photosynthetic organisms that efficiently capture light by utilizing the light-harvesting complexes called phycobilisomes. In many cyanobacteria, phycobilisomes are composed of an allophycocyanin core with phycocyanin and phycoerythrin (PE) rods radiating from the core. These phycobiliproteins have multiple bilin chromophores, such as phycoerythrobilin (PEB), covalently attached to specific cysteine (Cys) residues for efficient photosynthetic light capture. Chromophore ligation on phycobiliprotein subunits occurs through bilin lyase catalyzed reactions.
This study mainly focuses on characterizing the roles of enzymes that are involved in the biosynthetic pathway of the phycobiliproteins within two cyanobacteria Thermosynechococcus elongatus and Fremyella diplosiphon. A combination of molecular and biochemical techniques were used to better understand the roles of these proteins in the post-translational modification and/or stability of phycobiliproteins. Using a heterologous plasmid coexpression system in E. coli, recombinant CpcS-III from T. elongatus was shown to ligate three different bilins to both subunits of allophycocyanin and to the beta subunit of phycocyanin, thus, acting as a bilin lyase. The crystal structure of CpcS-III was also solved, the first bilin lyase structure.
Next, the roles of three proteins from F. diplosiphon CpeY, CpeZ, and CpeF were analyzed using a combination of gene knock-out mutants and recombinant protein expression techniques. In the absence of cpeY, chromophorylation to the alpha subunit of PE at Cys-82 was reduced, coinciding with the recombinant data that CpeY is the lyase that attaches PEB to this site. Removing cpeZ from the genome resulted in the destabilization and reduced accumulation of PE, especially the beta subunit CpeB. Recombinant CpeZ was shown to act like a chaperone-like protein and increased the solubility and fluorescence of both recombinant and native CpeB by increasing the stability of the phycobiliprotein and/or by increasing the activities of other lyases. The deletion of cpeF resulted in a reduced-PE phenotype with the doubly attached PEB missing from CpeB at Cys-48/Cys-59. Recombinant CpeF was shown to ligate PEB to CpeB-Cys-48/Cys-59 in the presence of recombinant CpeS (lyase attaches PEB to CpeB-Cys-80) and CpeZ. CpeF also showed a chaperone-like function by stabilizing CpeB, but its main role appears to be as a bilin lyase
In an Unending Desert of Cement and Skyscrapers: Lydia Cabrera, Revolutionary Cuba and Transnational Exile, 1960-1962
Get PDFThis thesis explores how the Cuban writer and anthropologist, Lydia Cabrera, experienced exile following the Cuban Revolution of 1959. Cabrera’s personal letters and photos show that she endured a nontypical exile experience. Instead, Cabrera is an example of a transnational exile, because throughout her life she remained both professionally and personally connected to people in multiple locations. Although discussion regarding the Cuban Revolution describes its transnational scope, for Cabrera and similar transnational figures, the events of 1959 meant a disruption to their longstanding international networks. In this way, this thesis will present evidence of Cabrera’s transnational connections and her response to disruption of these networks from 1960 – 1962. Key sources for this thesis can be found in the archival holdings at the University of Miami’s Cuban Historical Collection in Coral Gables, FL
Dividend Policy in a Frontier Market and Sector Equity Traded Funds in the United States
Get PDFIn chapter 1, we examine the nature and scale of the relationship between returns on sector Equity Traded Funds (ETFs) and their volatility. We discuss the source and direction of the effect between returns and risk and whether behavioral biases are prominent among sector ETFs. The study has implications for financial sector practitioners and investors, as it provides more information about the risk in sector ETF and whether that risk differs from that of other investment instruments. To this end, we test three hypotheses based on the relevant literature on volatility and returns: the leverage effect hypothesis, feedback hypothesis, and behavioral biases in assets pricing. We employ two measures of volatility in this chapter; specifically, we use the GARCH (1, 1) model and the Range-based autoregressive model.
Chapter 2 presents an examination of the factors that affect payout policy in a frontier market. MSCI classifies the Saudi stock exchange as a large frontier market and proposes to be reclassified as an emerging market by next year. The Saudi market is characterized by the high governmental influence and dominance of individual traders on daily transactions. By studying the 12-year panel data, we assess the effect government, board characteristics, social norms and major shareholder on Saudi firms’ decision to distribute dividends. The government presence and investor taste, especially for Islamic-compliant firms, are discussed. This chapter provides valuable information for investors and practitioners by identifying the factors that should be considered when making finance and investment decisions in frontier markets
Mechanisms of Invasion and Competition in Anolis sagrei and Anolis carolinensis lizards in southeastern Louisiana
Get PDFInvasive species can have a variety of effects on the behavior and ecology of native species. Currently in New Orleans, Louisiana, both A. sagrei and A. carolinensis lizards are relatively abundant, but the A. sagrei population is expanding rapidly. I used a combination of laboratory and field studies to investigate factors that might be influencing local dominance of invasive A. sagrei over native A. carolinensis populations, including habitat use, display behavior, interspecific aggressive interactions, and plasticity. When comparing display behavior and habitat use in anole populations across three field sites in southern Louisiana, I found differences in male display behavior of both species, and also that A. carolinensis perched higher when A. sagrei was present. In staged interspecific interactions, I discovered that A. sagrei females achieved consistently higher aggressive scores than A. carolinensis females, suggesting that female interspecific behavior is probably more important than male behavior in driving changes in habitat use. Lastly, I studied plasticity in several morphological and whole-organism performance variables by rearing males and females of each species on two different perch diameters. I found that sprinting performance in A. sagrei was significantly different between treatment groups, although the morphological differences between perch treatments were subtler than those reported in previous studies. I also found that A. carolinensis females exhibited significant differences in both sprinting and clinging performance, despite no significant differences in male or female morphology between perch size treatments, highlighting the potential for both species-specific and sex-specific plasticity
Twenty-two miniatures of the Tarot : a cycle for chamber ensemble
Get PDFTwenty-two miniatures of the Tarot is a cycle for chamber ensemble related to the twenty-two major arcana of the Tarot. Indeed, the intention of this composition is to capture the esoteric essence for each Major Arcana of the Tarot, making them speak musically in a contemporary language of music. Ideally, this cycle should be performed in the same order as the Tarot cycle, which has a number for each Major Arcana: 1) The Magician, 2) The High Priestess, 3) The Empress, 4) The Emperor, 5) The Pope, 6) The Lover, 7) The Chariot, 8) Justice, 9) The Hermit, 10) The Wheel of Fortune, 11) Strength, 12) The Hanged Man, 13) The Nameless Arcanum, 14) Temperance, 15) The Devil, 16) The Tower, 17) The Star, 18) The Moon, 19) The Sun, 20) Judgment, 21) The World and 22) The Fool
Global Market Liquidity and Corporate Investments
Get PDFThe dissertation consists of two essays. The first essay investigates how oil market factors impact on liquidity commonality in global equity markets. I identify two transmitting channels of the effect on liquidity commonality, namely oil price return and volatility. Using a sample of firms drawn from 50 countries spanning from Jan 1995 to Dec 2015, I find that both effects in oil explain the liquidity commonality in countries with higher integration to oil market. In addition, I show that oil volatility effect is more pronounced in net oil exporters compared to net oil importers after controlling for oil sensitivity. My findings suggest that oil volatility effect on liquidity commonality is more substantial for high oil sensitive countries than oil price return effect except five OPEC members, where liquidity commonality is highly influenced by oil the return along with volatility. These results are robust to controlling for possible sources of liquidity commonality as found in the literature. In the second essay, I study the impact of stock liquidity on firms’ future investments. Since stock liquidity decreases the cost of equity, I expect firms’ future investments to increase with stock liquidity. Secondly, I argue that this relation is more pronounced in more financially constrained firms because of their limited access to external capital. Using a sample of more than 9800 firms, from 21 emerging markets and spanning from 2000 to 2015, I find supportive and robust evidence of a positive association between stock liquidity and firms’ future investments. Furthermore, my findings strongly suggest that the liquidity impact on corporate investments is highly influenced by the firms’ financial constraint levels, using four different definitions of financial constraints. My findings are robust due to controlling for other determinants of future investment suggested in the previous literature, and due to controlling for the country and time effects. In addition, the results seem to be consistent with the use of alternative measures of corporate investments and stock liquidity and with alternative model specifications and estimation methodologies
Schedule and Cost Performance Analysis and Prediction in Louisiana DOTD
Get PDFMany construction projects in the United States are facing the risk of cost overrun and schedule delays. This is also happening here in the State of Louisiana. When these things happen, it causes cost overrun which can then be passed on to the tax payers and may also cause the state to take on less projects than they normal. Many researchers have studied the reasons behind both the cost overrun and the delays resulting in private firms, developing project management tools and best practices to prevent this risk. In this research, I aim to study the historical trend in 2912 publically funded projects in the State of Louisiana. The study will reveal the overall state level of accuracy of forecasting cost and schedule. A forecasting formula based on those historical projects will be developed to assist estimators at the Parish level in predicting cost and schedule performance.
The State of Louisiana has so many projects that deal with the transportation system (roadway, bridges, drainage, traffic sign, traffic signal, lighting etc...)
My Dissertation will be a study and analysis of time and cost of the projects in LADOTD, whether the projects finish on time, before time or after time as well as the cost of the project that has been completed overrun or underrun or the exact amount that the bid amount was. With this study and analysis, my intention is to create time schedule and cost to be used to on reaching accuracy on finishing the project on time and the exact bid amount of the project (exclude whether condition, extra work, and some unexpected problems that may arise during the length of the project)
Study of Static and Dynamic Properties of Magnetic Nanostructures
Get PDFMagnetic materials are one of the most interesting and promising class of materials for technological applications [1]. Among them, patterned ferromagnetic systems have an important role especially in the prospect of high density data storage [2], domain wall logic devices [3] and magnetic memory [4, 5]. Coupled systems of ferromagnetic and antiferromagnetic materials have been implemented to design sensors such as giant magnetoresistance (GMR) [6-8] and tunnel magnetoresistance (TMR) [9, 10]. Ferromagnetic nanoparticles have been used for the drug targeting, cancer therapy, MRI and many more applications [11, 12]. In addition, more recently, significant attention has been paid to explore the dynamic properties of magnetic materials in the GHz range and use them for technological applications such as microwave filters, signal processing, phase shifter, nonreciprocal microwave devices, spin wave guide, high frequency memory, logic elements [13-19]
Boundary conditions, interactions between individual entities, and lateral confinement of magnetic charges generate diverse magnetic properties especially at nanoscale length [20, 21]. The variation of magnetic properties are even quite different when the size of the magnetic structure is smaller or comparable with the magnetic characteristic length such as mean free path of electron, width of domain wall and even the spin diffusion length [22-24].
In this study, we have considered different magnetic systems. Firstly, the multilayer of coupled ferromagnetic and antiferromagnetic system has been considered to evaluate the exchange bias anisotropy. [FeNi/IrMn]n multilayer systems with different thicknesses of ferromagnetic layer were studied. Static and dynamic properties were revealed through magnetometry measurements (VSM) and VNA-FMR techniques respectively. Angular variation of first order reversal curve (AFORC) and ferromagnetic resonance (AFMR) were performed to learn the intrinsic exchange bias distribution. Secondly, patterned magnetic structures were synthesized to understand the magnetization dynamics in confined geometry. Surface modulated thin films with different periodicity, dumbbell-shaped structures with variable size and three dimensional magnonic crystals have been studied using both static and dynamic measurement techniques. Micromagnetic simulations were performed to understand and explain the experimental results
Role of Ime4 and Pho92 Proteins in Pho5 Regulation
Get PDFIn the yeast Saccharomyces cerevisiae, m6A methylation regulates the stability and translation of mRNA. Ime4, which is highly active in meiotic cells, recognizes consensus methyl sites in pre-mRNA and adds methyl groups to a small fraction of adenosine residues, whereas Pho92 binds to such methylated sites and promotes subsequent degradation. PHO5 transcripts expression is upregulated when IME4 and PHO92 are deleted. In the PHO5 transcript, near the stop codon of the open reading frame (ORF), there is a potential consensus methyl site that is predicted to be methylated, based on its location and excellent match to the consensus methylation sequence (Schwartz et al. 2013). We believe that this 3’ region, containing potential methyl site, may be involved in the transcript regulation. We tested this hypothesis by examining the change in expression of GFP-Pho5 fusion proteins under the control of ADH1 promoter. These experiments were done using Δime4, Δpho92 and Δime4 Δpho92 deletions in haploid and vegetative growing Saccharomyces cerevisiae. Although the results of these experiments were inconclusive for Ime4, we confirmed that Pho92 cannot act solely on the 3’ region; it needs the PHO5 ORF to promote its activity. We suggest that Pho92 promotes PHO5 transcript degradation by an alternative pathway, which is not dependent on methylation of the target transcript