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 Collection: UNT Theses and Dissertations
Source Apportionment Analysis of Measured Volatile Organic Compounds in Corpus Christi, Texas

Source Apportionment Analysis of Measured Volatile Organic Compounds in Corpus Christi, Texas

Date: May 2014
Creator: Abood, Ahmed T.
Description: Corpus Christi among of the largest industrialized coastal urban areas in Texas. The strategic location of the city along the Gulf of Mexico allows for many important industries and an international business to be located. The cluster of industries and businesses in the region contribute to the air pollution from emissions that are harmful to the environment and to the people living in and visiting the area. Volatile organic compounds (VOC) constitute an important class of pollutants measured in the area. The automated gas chromatography (Auto GC) data was collected from Texas Commission of Environmental Quality (TCEQ) and source apportionment analysis was conducted on this data to identify key sources of VOC affecting this study region. EPA PMF 3.0 was employed in this sources apportionment study of measured VOC concentration during 2005 - 2012 in Corpus Christi, Texas. The study identified nine optimal factors (Source) that could explain the concentration of VOC at two urbane monitoring sites in the study region. Natural gas was found to be the largest contributor of VOC in the area, followed by gasoline and vehicular exhaust. Diesel was the third highest contributor with emissions from manufacturing and combustion processes. Refineries gases and evaporative fugitive emissions ...
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Boosting for Learning From Imbalanced, Multiclass Data Sets

Boosting for Learning From Imbalanced, Multiclass Data Sets

Access: Use of this item is restricted to the UNT Community.
Date: December 2013
Creator: Abouelenien, Mohamed
Description: In many real-world applications, it is common to have uneven number of examples among multiple classes. The data imbalance, however, usually complicates the learning process, especially for the minority classes, and results in deteriorated performance. Boosting methods were proposed to handle the imbalance problem. These methods need elongated training time and require diversity among the classifiers of the ensemble to achieve improved performance. Additionally, extending the boosting method to handle multi-class data sets is not straightforward. Examples of applications that suffer from imbalanced multi-class data can be found in face recognition, where tens of classes exist, and in capsule endoscopy, which suffers massive imbalance between the classes. This dissertation introduces RegBoost, a new boosting framework to address the imbalanced, multi-class problems. This method applies a weighted stratified sampling technique and incorporates a regularization term that accommodates multi-class data sets and automatically determines the error bound of each base classifier. The regularization parameter penalizes the classifier when it misclassifies instances that were correctly classified in the previous iteration. The parameter additionally reduces the bias towards majority classes. Experiments are conducted using 12 diverse data sets with moderate to high imbalance ratios. The results demonstrate superior performance of the proposed method compared ...
Contributing Partner: UNT Libraries
Finitness and Verb-Raising in Second Language Acquisition of French by Native Speakers of Moroccan Arabic

Finitness and Verb-Raising in Second Language Acquisition of French by Native Speakers of Moroccan Arabic

Date: August 1996
Creator: Aboutaj, Heidi H. (Heidi Huttar)
Description: In this thesis, the three hypotheses on the nature of early L2 acquisition (the Full Transfer/Full Access view of Schwartz and Sprouse (e.g., 1996), the Minimal Trees view of Vainikka and Young-Scholten (e.g., 1996), and the Valueless Features view of Eubank (e.g., 1996)), are discussed. Analysis of the early French production by two native speakers of Moroccan Arabic is done to determine if the L1 grammar is transferred onto the L2 grammar. In particular, the phenomena of verb-raising (as determined by the verb's position vis-a-vis negation) and finiteness are examined. The results of this study indicate that the relevant structures of Moroccan Arabic do not transfer onto the emerging French grammar.
Contributing Partner: UNT Libraries
Derivatives of 1,4-Naphthoquinone and 1,4-Anthraquinone

Derivatives of 1,4-Naphthoquinone and 1,4-Anthraquinone

Date: August 1959
Creator: Aboytes, Peter
Description: The purpose of this investigation was the synthesis of some 1,4-naphthoquinones and 1,4-anthraquinones. It will be shown that some of these substituted quinones exhibit physiological properties.
Contributing Partner: UNT Libraries
Development of a Cost Effective Wireless Sensor System for Indoor Air Quality Monitoring Applications

Development of a Cost Effective Wireless Sensor System for Indoor Air Quality Monitoring Applications

Date: May 2014
Creator: Abraham, Sherin
Description: Poor air quality can greatly affect the public health. Research studies indicate that indoor air can be more polluted than the outdoor air. An indoor air quality monitoring system will help to create an awareness of the quality of air inside which will eventually help in improving it. The objective of this research is to develop a low cost wireless sensor system for indoor air quality monitoring. The major cost reduction of the system is achieved by using low priced sensors. Interface circuits had to be designed to make these sensors more accurate. The system is capable of measuring carbon dioxide, carbon monoxide, ozone, temperature, humidity and volatile organic compounds. The prototype sensor node modules were developed. The sensor nodes were the connected together by Zigbee network. The nodes were developed in such a way that it is compact in size and wireless connection of sensor nodes enable to collect air quality data from multiple locations simultaneously. The collected data was stored in a computer. We employed linear least-square approach for the calibration of each sensor to derive a conversion formula for converting the sensor readings to engineering units. The system was tested with different pollutants and data collected was ...
Contributing Partner: UNT Libraries
An Art Program Utilizing Discarded Materials in the Improvement of Interiors of Homes of Children in a Low Income Group

An Art Program Utilizing Discarded Materials in the Improvement of Interiors of Homes of Children in a Low Income Group

Date: January 1960
Creator: Abram, W. B.
Description: The problem with which this investigation is concerned is that of planning and carrying out an art program in which a particular group of students in a low income group, by utilizing discarded and inexpensive materials, can create useful and satisfying objects for the improvement of their home interiors.
Contributing Partner: UNT Libraries
Ultrastructural Changes of Tumor Implants in Mice

Ultrastructural Changes of Tumor Implants in Mice

Date: January 1970
Creator: Abrams, Joe A.
Description: The purpose of this investigation was to observe the sequential ultrastructural changes in tumor implants of a well established tumor line in isologous mice.
Contributing Partner: UNT Libraries
Ultrafast Laser Sampling of a Plant Tissue and ion Conductivity Measurement for Investigation of Light Stress Generation Mechanisms

Ultrafast Laser Sampling of a Plant Tissue and ion Conductivity Measurement for Investigation of Light Stress Generation Mechanisms

Date: August 2010
Creator: Abtahi, Seyed Ali
Description: In this study we applied ultra-short laser pulses on a biological sample (Arabidopsis), in order to cut it precisely in a square pattern and subsequently use it for studying stress generation mechanisms. For this purpose, we utilized femtosecond laser pulses at 100 fs pulse width and 80 MHz repetition rate. We took two processing parameters into consideration such as laser power, laser exposure time which is related to the stage speed. Therefore, we were able to find the laser optimum conditions for ablation of biological tissues. The mutant and wildtype (control) obtained from laser cutting with a size of 500 µm × 500 µm were directly transferred (in-situ with laser cutting) into a microfabricated chamber containing ~500 nanoliters deionized water for measuring ion conductivity. The ion conductivity is a signature of cell-death mechanisms caused by various stresses. A light with intensity of 100 µmol was exposed to the samples for 2 hours and 20 minutes as a source of stress. A quantitative electrical analysis with high accuracy was assured by utilizing a microchamber, which enables a measurement in nanoliter volume. We measured the impedance which is reciprocal of conductivity using a lock-in amplifier and a precise current source at frequency ...
Contributing Partner: UNT Libraries
Application of Synthetic Peptides as Substrates for Reversible Phosphorylation

Application of Synthetic Peptides as Substrates for Reversible Phosphorylation

Date: August 1992
Creator: Abukhalaf, Imad Kazem
Description: Two highly homologous synthetic peptides MLC(3-13) (K-R-A-K-A-K-T-TK-K-R-G) and MLC(5-13) (A-K-A-K-T-T-K-K-R-G) corresponding to the amino terminal amino acid sequence of smooth muscle myosin light chain were utilized as substrates for protein kinase C purified from murine lymphosarcoma tumors to determine the role of the primary amino acid sequence of protein kinase C substrates in defining the lipid (phosphatidyl serine and diacylglycerol) requirements for the activation of the enzyme. Removal of the basic residues lysine and arginine from the amino terminus of MLC(3-13) did not have a significant effect on the Ka value of diacylglycerol. The binding of effector to calcium-protein kinase C appears to be random since binding of one effector did not block the binding of the other.
Contributing Partner: UNT Libraries
Corporate Christians and Terrible Turks: Economics, Aesthetics, and the Representation of Empire in the Early British Travel Narrative, 1630 - 1780

Corporate Christians and Terrible Turks: Economics, Aesthetics, and the Representation of Empire in the Early British Travel Narrative, 1630 - 1780

Date: December 2003
Creator: Abunasser, Rima Jamil
Description: This dissertation examines the evolution of the early English travel narrative as it relates to the development and application of mercantilist economic practices, theories of aesthetic representation, and discourses of gender and narrative authority. I attempt to redress an imbalance in critical work on pre-colonialism and colonialism, which has tended to focus either on the Renaissance, as exemplified by the works of critics such as Stephen Greenblatt and John Gillies, or on the later eighteenth and early nineteenth centuries, as in the work of scholars such as Srinivas Aravamudan and Edward Said. This critical gap has left early travel narratives by Sir Francis Moore, Jonathan Harris, Penelope Aubin, and others largely neglected. These early writers, I argue, adapted the conventions of the travel narrative while relying on the authority of contemporary commercial practices. The early English travelers modified contemporary conventions of aesthetic representation by formulating their descriptions of non-European cultures in terms of the economic and political conventions and rivalries of the early eighteenth century. Early English travel literature, I demonstrate, functioned as a politically motivated medium that served both as a marker of authenticity, justifying the colonial and imperial ventures that would flourish in the nineteenth century, and as ...
Contributing Partner: UNT Libraries