You limited your search to:

  Access Rights: Use restricted to UNT Community
 Decade: 2010-2019
 Collection: UNT Theses and Dissertations
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
Novel Role of Trypsin in Zebrafish

Novel Role of Trypsin in Zebrafish

Access: Use of this item is restricted to the UNT Community.
Date: May 2013
Creator: Alsrhani, Abdullah Falleh
Description: It has been shown previously in our laboratory that zebrafish produce trypsin from their gills when they are under stress, and this trypsin is involved in thrombocyte activation via PAR2 during gill bleeding. In this study, I investigated another role of the trypsin that is secreted from zebrafish. This investigation has demonstrated a novel role of trypsin in zebrafish. Not only did this investigation demonstrate the role of trypsin in zebrafish behavior, but also it showed that PAR2 might be the receptor that is involved in trypsin-mediated behavioral response. In addition, we have shown that Gq and ERK inhibitors are able to block the trypsin pathway and prevent the escaping behavior. Finally, the results of this investigation suggest that the cells that respond to trypsin are surface cells, which have an appearance similar to that of neuromast cells.
Contributing Partner: UNT Libraries
Witchcraft: a Targeted Societal Discrimination Against Women in Northern Ghana

Witchcraft: a Targeted Societal Discrimination Against Women in Northern Ghana

Access: Use of this item is restricted to the UNT Community.
Date: December 2013
Creator: Atumah, Oscar Nwagbo
Description: A combination of aging and poverty is becoming dominant in African society today, at a time when African countries are expected to be recovering from poverty, and are projected to house the economic growth of the next century. The emergence of aging in African context and the aging of the world population will expose the weakness of the current mechanisms used for older people around the world. As economies grow around the world, the distribution gap between the affluent and the poor widens, and the constant struggles for wealth, power, and social status, amidst scarce resources, continue to be sustained. To remain in charge of economic resources, the powerful few devise means to disenfranchise the weak, and witchcraft accusation is one of such tools used in Northern Ghana today. A new wave of witchcraft accusation has caught the attention of many in Northern Ghana. These victims with certain socioeconomic characteristics appear helpless and without defense against such accusations. As a result, they suffer untold hardships and are often compelled to leave their homes and to reside in camps reserved for witches. This study was undertaken to identify those sociodemographic characteristics, which are commonly shared by witchcraft accusation victims. These sociodemographic ...
Contributing Partner: UNT Libraries
Functional Characterization of Mtnip/latd’s Biochemical and Biological Function

Functional Characterization of Mtnip/latd’s Biochemical and Biological Function

Access: Use of this item is restricted to the UNT Community.
Date: December 2013
Creator: Bagchi, Rammyani
Description: Symbiotic nitrogen fixation occurs in plants harboring nitrogen-fixing bacteria within the plant tissue. The most widely studied association is between the legumes and rhizobia. In this relationship the plant (legumes) provides the bacteria (rhizobia) with reduced carbon derived from photosynthesis in exchange for reduced atmospheric nitrogen. This allows the plant to survive in soil, which is low in available of nitrogen. Rhizobia infect and enter plant root and reside in organs known as nodules. In the nodules the bacteria fix atmospheric nitrogen. The association between the legume, Medicago truncatula and the bacteria Sinorhizobium meliloti, has been studied in detail. Medicago mutants that have defects in nodulation help us understand the process of nitrogen fixation better. One such mutant is the Mtnip-1. Mtnip-1 plants respond to S. meliloti by producing abnormal nodules in which numerous aberrant infection threads are produced, with very rare rhizobial release into host plant cells. The mutant plant Mtnip-1 has an abnormal defense-like response in root nodules as well as defects in lateral root development. Three alleles of the Mtnip/latd mutants, Mtnip-1, Mtlatd and Mtnip-3 show different degrees of severity in their phenotype. Phylogenetic analysis showed that MtNIP/LATD encodes a protein belonging to the NRT1(PTR) family of ...
Contributing Partner: UNT Libraries
American Indian Worldviews, Risk Perceptions and Disaster Planning: an Exploratory Study

American Indian Worldviews, Risk Perceptions and Disaster Planning: an Exploratory Study

Access: Use of this item is restricted to the UNT Community.
Date: December 2013
Creator: Bales, Rodney A.
Description: It is commonly assumed that when confronted with an imminent hazard that people will react rationally, and prepare for, or at least attempt to avoid, danger from pending disasters. However, this conventional wisdom is not as evident as it appears. People prepare for, react to, or take social action to avoid hazards when they perceive the risk of danger to be threatening enough to warrant action, providing one has the will, insight and resources to do so. However, not all people perceive risks similarly. Risk is perceived differently by different people which affects risk perception and responses to hazards. This dissertation explores the relationships between American Indian worldviews, risk perceptions and disaster planning. To carry out this research 28 American Indians were interviewed. The sample consists of 14 American Indians residing in a rural are on the northern plains and 14 urban American Indians. The results only partially support that worldview is linked to risk perception and subsequent disaster planning. Other factors found to relate to risk perception and disaster planning for this non-representative sample of American Indians include various forms of social vulnerability.
Contributing Partner: UNT Libraries
The “Nigger Trinity”: Engaging the Discourse in Post Civil Rights/Post 1960s America

The “Nigger Trinity”: Engaging the Discourse in Post Civil Rights/Post 1960s America

Access: Use of this item is restricted to the UNT Community.
Date: December 2011
Creator: Bell, Adrian Shane
Description: The cultural and popular media landscape of the United States of America changed after the Civil-Rights movement of the 1960s. The word “Nigger” was changed during that same period of American history. There are several authors and a comic that helped change this word during the 1960s. The post Civil-Rights American has a different experience and understanding with this word than those born before 1970. This work triangulates the current cultural location of the word “Nigger,” “nigga,” and “the n-word” using linguistics, law, and two media case studies. The “Nigger” trinity is a model that adds value to the discourse that surrounds this one word in post civil-rights/post 1960s America.
Contributing Partner: UNT Libraries
Between Comancheros and Comanchería: a History of Fort Bascom, New Mexico

Between Comancheros and Comanchería: a History of Fort Bascom, New Mexico

Access: Use of this item is restricted to the UNT Community.
Date: August 2012
Creator: Blackshear, James Bailey
Description: In 1863, Fort Bascom was built along the Canadian River in the Eroded Plains of Territorial New Mexico. Its unique location placed it between the Comanches of Texas and the Comancheros of the Sangre de Cristo Mountains. This post was situated within Comanchería during the height of the United States Army's war against the Southern Plains Indians, yet it has garnered little attention. This study broadens the scholarly understanding of how the United States Army gained control of the Southwest by examining the role Fort Bascom played in this mission. This includes an exploration of the Canadian River Valley environment, an examination of the economic relationship that existed between the Southern Plains Indians and the mountain people of New Mexico, and an account of the daily life of soldiers posted to Fort Bascom. This dissertation thus provides an environmental and cultural history of the Canadian River Valley in New Mexico, a social history of the men stationed at Fort Bascom, and proof that the post played a key role in the Army's efforts to gain control of the Southern Plains Indians. This study argues that Fort Bascom should be recognized as Texas' northern-most frontier fort. Its men were closer to ...
Contributing Partner: UNT Libraries
Portraits: A Collection

Portraits: A Collection

Access: Use of this item is restricted to the UNT Community.
Date: May 2010
Creator: Boswell, Timothy
Description: This collection consists of a critical preface and five short stories. The preface analyzes what it terms 'fringe fiction,' or stories dealing with elements that are improbable or unusual, though not impossible, as it distinguishes this category from magical realism and offers guidelines for writing this kind of fiction. The short stories explore themes of attachment, loss, guilt, and hope. Collection includes the stories "Portrait," "Dress Up," "Change," "Drawn Onward, We Few, Drawn Onward," and "Broker."
Contributing Partner: UNT Libraries
Southern Promise and Necessity:  Texas, Regional Identity, and the National Woman Suffrage Movement, 1868-1920

Southern Promise and Necessity: Texas, Regional Identity, and the National Woman Suffrage Movement, 1868-1920

Access: Use of this item is restricted to the UNT Community.
Date: August 2010
Creator: Brannon-Wranosky, Jessica S.
Description: This study offers a concentrated view of how a national movement developed networks from the grassroots up and how regional identity can influence national campaign strategies by examining the roles Texas and Texans played in the woman suffrage movement in the United States. The interest that multiple generations of national woman suffrage leaders showed in Texas, from Reconstruction through the ratification of the Nineteenth Amendment, provides new insights into the reciprocal nature of national movements. Increasingly, from 1868 to 1920, a bilateral flow of resources existed between national women's rights leaders and woman suffrage activists in Texas. Additionally, this study nationalizes the woman suffrage movement earlier than previously thought. Cross-regional woman suffrage activity has been marginalized by the belief that campaigning in the South did not exist or had not connected with the national associations until the 1890s. This closer examination provides a different view. Early woman's rights leaders aimed at a nationwide movement from the beginning. This national goal included the South, and woman suffrage interest soon spread to the region. One of the major factors in this relationship was that the primarily northeastern-based national leadership desperately needed southern support to aid in their larger goals. Texas' ability to ...
Contributing Partner: UNT Libraries
Henderson Street Bazaar and Other Stories

Henderson Street Bazaar and Other Stories

Access: Use of this item is restricted to the UNT Community.
Date: December 2010
Creator: Briseño, J. Andrew
Description: The preface, "Against Buses: Charles Baxter and the Contemporary Epiphany" deals with the epiphany as a potential ending to short stories. Baxter holds that epiphanies are trite and without purpose in today's fiction. I argue that Baxter's view, while not without merit, is limiting. Beginning with James Joyce and Katherine Anne Porter and moving to my own work, I discuss how some epiphanies, particularly false ones, can enhance rather than detract from excellent fiction. Five short stories make up the remainder of this thesis: "Dedication," "Taking it with You," "Transition to Flowers," "Profile in Courage," and "Henderson Street Bazaar."
Contributing Partner: UNT Libraries
FIRST PREV 1 2 3 4 5 NEXT LAST