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Fundamental Studies of Copper Bimetallic Corrosion in Ultra Large Scale Interconnect Fabrication Process

Fundamental Studies of Copper Bimetallic Corrosion in Ultra Large Scale Interconnect Fabrication Process

Date: May 2014
Creator: Koskey, Simon Kibet
Description: In this work, copper bimetallic corrosion and inhibition in ultra large scale interconnect fabrication process is explored. Corrosion behavior of physical vapor deposited (PVD) copper on ruthenium on acidic and alkaline solutions was investigated with and without organic inhibitors. Bimetallic corrosion screening experiments were carried out to determine the corrosion rate. Potentiodynamic polarization experiments yielded information on the galvanic couples and also corrosion rates. XPS and FTIR surface analysis gave important information pertaining inhibition mechanism of organic inhibitors. Interestingly copper in contact with ruthenium in cleaning solution led to increased corrosion rate compared to copper in contact with tantalum. On the other hand when cobalt was in contact with copper, cobalt corroded and copper did not. We ascribe this phenomenon to the difference in the standard reduction potentials of the two metals in contact and in such a case a less noble metal will be corroded. The effects of plasma etch gases such as CF4, CF4+O2, C4F8, CH2F2 and SF6 on copper bimetallic corrosion was investigated too in alkaline solution. It was revealed that the type of etching gas plasma chemistry used in Cu interconnect manufacturing process creates copper surface modification which affects corrosion behavior in alkaline solution. The learning ...
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Sensitivity and Uncertainty Analysis of Occupancy-related Parameters in Energy Modeling of Unt Zero Energy Lab

Sensitivity and Uncertainty Analysis of Occupancy-related Parameters in Energy Modeling of Unt Zero Energy Lab

Date: August 2013
Creator: Xiong, Guangyuan
Description: The study focuses on the sensitivity and uncertainty analysis of occupancy-related parameters using Energyplus modeling method. The model is based on a real building Zero Energy Lab in Discovery Park, at University of North Texas. Four categories of parameters are analyzed: heating/cooling setpoint, lighting, equipment and occupancy. Influence coefficient (IC) is applied in the sensitivity study, in order to compare the impact of individual parameter on the overall building energy consumption. The study is conducted under Texas weather file as well as North Dakota weather file in order to find weather’s influence of sensitivity. Probabilistic collocation method (PCM) is utilized for uncertainty analysis, with an aim of predicting future energy consumption based on history or reference data set. From the study, it is found that cooling setpoint has the largest influence on overall energy consumption in both Texas and North Dakota, and occupancy number has the least influence. The analysis also indicates schedule’s influence on energy consumption. PCM is able to accurately predict future energy consumption with limited calculation, and has great advantage over Monte Carlo Method. The polynomial equations are generated in both 3-order and 6-order, and the 6-order equation is proved to have a better result, which is ...
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The Effect of Natural Gas Well Setback Distance on Drillable Land in the City of Denton, Texas

The Effect of Natural Gas Well Setback Distance on Drillable Land in the City of Denton, Texas

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Date: May 2014
Creator: Daniel, Michael
Description: Municipalities protect human health and environmental resources from impacts of urban natural gas drilling through setback distances; the regulation of distances between well sites and residences, freshwater wells, and other protected uses. Setback distances have increased over time, having the potential to alter the amount and geographical distribution of drillable land within a municipality, thereby having implications for future land use planning and increasing the potential for future incompatible land uses. This study geographically applies a range of setback distances to protected uses and freshwater wells in the city limits of Denton, Texas to investigate the effect on the amount of land remaining for future gas well development and production. Denton lies on the edge of a productive region of the Barnett Shale geological formation, coinciding with a large concentration of drillable land in the southwestern region of the study area. This region will have the greatest potential for impacts to future municipal development and land use planning as a result of future gas well development and higher setback standards. Given the relatively high acreage of drillable land in industrially zoned subcategory IC-G and the concern regarding gas well drilling in more populated areas, future drilling in IC-G, specifically in ...
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Reading Beyond the Words: How Implementing Esl Strategies During Modified Guided Reading Affects a Deaf Student’s Language Acquisition Process

Reading Beyond the Words: How Implementing Esl Strategies During Modified Guided Reading Affects a Deaf Student’s Language Acquisition Process

Date: August 2013
Creator: Christian, Laura
Description: While Deaf students are not typically classified as English as a second language (ESL) students, the majority of deaf students first become fluent in a signed language, making them ideal candidates for ESL research. This case study has been designed to explore the ways in which one method of ESL reading instruction, known as modified guided reading (MGR), affects the language acquisition process, and resulting reading comprehension level, of a deaf student over eleven weeks. The study documented the student’s language acquisition development both in American Sign Language (ASL) and in English, as well as tracked the student’s growth in reading comprehension, metalinguistic awareness, and visual attention skills. The Accelerated Reader (AR) program, benchmark testing, and daily observations were used to measure growth. Findings of the study suggest that the ESL methods implemented through MGR positively impacted the student’s language acquisition process, reading comprehension level, metalinguistic awareness, and visual attention skills. Results showed an increase in all three of the student’s AR scores as follows: 31% in reading level, 13.1% in number of words read, and 13.2 % in comprehension test scores. Observations and benchmark testing revealed increased metalinguistic knowledge in word, syntactic, and pragmatic awareness. Visual attention skills were ...
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Études: Five Compositional and Technical Studies for Solo Organ

Études: Five Compositional and Technical Studies for Solo Organ

Date: May 2014
Creator: Lloyd, S. Andrew
Description: Études was composed as a set of five interrelated movements in the followingorder: Prelude, Introduction and Fugue, Triptych, Chorale, and Response. The pieces are compositional as well as technical studies. The movements specifically explore certain styles and forms unique to organ music, and reintroduce these elements in creative ways. As in the traditional étude, each movement contains virtuosic technical studies, which are designed to enhance manual and pedal facility and prepare the performer for advanced repertoire.
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Spatial Ability in Registered Nurses

Spatial Ability in Registered Nurses

Date: May 2014
Creator: Gardner, Janet E.
Description: Spatial ability is the skill associated with mental relations among objects, the process of maintaining the physical aspects of an object after mentally rotating it in space. Many studies report a strong association of spatial ability with success in various areas of health care, especially surgery, radiology and dentistry. To date, similar investigations in professional nursing could not be located. Registered nurses, employed in an acute care multi-hospital setting, were surveyed using the Shipley-2Block Pattern Test, the Group Embedded Figures Test, and a newly created test of general nursing knowledge. The sample size of 123 nurses was composed of 31 male nurses and 92 female nurses. Data was collected between May and August of 2013 and analyzed using R, version 2.15.2. The present study did not demonstrate a statistically significant effect for gender differences on two measures of spatial ability. However, Cohen’s d effect sizes for mean gender differences in the present study are consistent with prior studies. This may suggest the nursing profession is comparable with other professions where males perform higher than females on spatial ability. The present study should be considered an initial step toward evaluating the relevance of spatial ability in the performance of nursing care.
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A Performance Analysis of Solar Chimney Passive Ventilation System in the Unt Zero Energy Lab

A Performance Analysis of Solar Chimney Passive Ventilation System in the Unt Zero Energy Lab

Date: August 2013
Creator: Talele, Suraj H.
Description: The purpose of this investigation is to find out suitability of the solar chimney natural ventilation system in a Zero Energy Lab located at the University of North Texas campus, to figure out performance of the solar chimney. Reduction in the heating and ventilation and air conditioning energy consumption of the house has been also analyzed. The parameters which are considered for investigation are volumetric flow rate of outlet of chimney, the absorber wall temperature and glass wall temperatures. ANSYS FLUENT 14.0 has been employed for the 3-D modeling of the solar chimney. The dimensions of the solar chimney are 14’2” X 7’4” X 6’11”. The flow inside solar chimney is found to be laminar and the simulation results show that maximum outlet volumetric flow rate of about 0.12m3/s or 432 cfm is possible from chimney. The experimental velocity of chimney was found to be 0.21 m/s. Density Boussinesq approximation is considered for the modeling. Velocity and temperature sensors have been installed at inlet and outlet of the chimney in order to validate the modeling results. It is found that based on simulated volumetric flow rate that cooling load of 9.29 kwh can be saved and fan power of 7.85 ...
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A Pedagogical and Methodical Approach to Unaccompanied Euphonium Literature Through Performance and Analyses of Original Works by Torstein Aagaard-nilsen

A Pedagogical and Methodical Approach to Unaccompanied Euphonium Literature Through Performance and Analyses of Original Works by Torstein Aagaard-nilsen

Date: August 2013
Creator: Nyren, Patrick J.
Description: Original unaccompanied literature currently stands as one of the most understudied bodies of music in the euphonium repertory. This is largely due to a lack of access to reference recordings, live performances, and study/performance guides. Many of the commissioning projects for new euphonium music in the late 20th and early 21st centuries have promoted the composition of large scale works for euphonium and large ensembles, but very few have generated new unaccompanied pieces for euphonium. Many of the most recent commissions for unaccompanied euphonium music have been for competitions such as the Lieksa Brass Festival (Finland) and Leonard Falcone International Festival (USA). These competitions are also where many students get their only exposure to the unaccompanied repertoire. Unfortunately, there is a small number of standard unaccompanied works that are continuously recycled for these competitions and the exposure to new pieces in the repertoire is further diminished for many developing euphoniumists. This study will examine the three works for unaccompanied euphonium by Torstein Aagaard-Nilsen and provide solutions for many common technical challenges and pose suggestions for approaching and preparing this genre of music. Connections are made throughout the study to specific etudes and other unaccompanied solos that can be used as ...
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A Study of Silver: an Alternative Maldi Matrix for Low Weight Compounds and Mass Spectrometry Imaging

A Study of Silver: an Alternative Maldi Matrix for Low Weight Compounds and Mass Spectrometry Imaging

Date: May 2014
Creator: Walton, Barbara Lynn
Description: Soft-landing ion mobility has applicability in a variety of areas. The ability to produce material and collect a sufficient amount for further analysis and applications is the key goal of this technique. Soft-landing ion mobility has provided a way to deposit material in a controllable fashion, and can be tailored to specific applications. Changing the conditions at which soft-landing ion mobility occurs effects the characteristics of the resulting particles (size, distribution/coverage on the surface). Longer deposition times generated more material on the surface; however, higher pressures increased material loss due to diffusion. Larger particles were landed when using higher pressures, and increased laser energy at ablation. The utilization of this technique for the deposition of silver clusters has provided a solvent free matrix application technique for MALDI-MS. The low kinetic energy of incident ions along with the solvent free nature of soft-landing ion mobility lead to a technique capable of imaging sensitive samples and low mass analysis. The lack of significant interference as seen by traditional organic matrices is avoided with the use of metallic particles, providing a major enhancement in the ability to analyze low mass compounds by MALDI.
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Remembering the Forgotten D-day: the Amphibious Landing at Collado Beach During the Mexican War

Remembering the Forgotten D-day: the Amphibious Landing at Collado Beach During the Mexican War

Date: May 2014
Creator: Menking, Christopher N.
Description: The current historiography of the Mexican War does not give due credit to the significance of the landing at Collado Beach. No one source addresses all aspects of the landing, nor have any included an analysis of the logistical side of the operation. This thesis presents a comprehensive analysis of the operation from conception to execution in an attempt to fill the gap in the historiography. Additionally, the lessons learned and lessons forgotten from this landing are addressed as to how this landing shaped American military doctrine regarding joint operations and amphibious operations. The conclusion drawn from the historical sources supports the argument that this operation had a significant impact on the American military. The influence of this operation shows itself throughout American military history, including the establishment of amphibious doctrine by the Unites States Marine Corps and during World War II.
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