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2006

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Developments And Hurdles In Generating Vaccines For Controlling Helminth Parasites Of Grazing Ruminants, W.D. Smith, D.S. Zarlenga Jan 2006

Developments And Hurdles In Generating Vaccines For Controlling Helminth Parasites Of Grazing Ruminants, W.D. Smith, D.S. Zarlenga

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

As a direct consequence of rising drug resistance among common nematodes of grazing animals, efforts toward state-of-the- art vaccine development have clearly intensified in recent years, fuelled primarily by the advent of newer technologies in gene discovery, by advancements in antigen identification, characterisation and production. In this regard, it is appropriate to review progress that has been made in generating helminth vaccines and in particular, vaccines against common nematodes of production animals for consumption. In like manner, it is prudent to evaluate barriers that have hindered progress in the past and continue to present obstacles that must be solved when …

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The Integral Cohomology Of The Group Of Loops, Craig Jensen, Jon Mccammond, John Meier Jan 2006

The Integral Cohomology Of The Group Of Loops, Craig Jensen, Jon Mccammond, John Meier

Mathematics Faculty Publications

No abstract provided.

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On Improving Wireless Broadcast Reliability Of Sensor Networks Using Erasure Codes, Rajnish Kumar, Arnab Paul, Umakishore Ramachandran, David Kotz Jan 2006

On Improving Wireless Broadcast Reliability Of Sensor Networks Using Erasure Codes, Rajnish Kumar, Arnab Paul, Umakishore Ramachandran, David Kotz

Dartmouth Scholarship

Efficient and reliable dissemination of information over a large area is a critical ability of a sensor network for various reasons such as software updates and transferring large data objects (e.g., surveillance images). Thus efficiency of wireless broadcast is an important aspect of sensor network deployment. In this paper, we study FBcast, a new broadcast protocol based on the principles of modern erasure codes. We show that our approach provides high reliability, often considered critical for disseminating codes. In addition FBcast offers limited data confidentiality. For a large network, where every node may not be reachable by the source, we …

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Differences In Academic Performance And Self-Regulated Learning Based On Level Of Student Participation In Supplemental Instruction, Ana Mack Jan 2006

Differences In Academic Performance And Self-Regulated Learning Based On Level Of Student Participation In Supplemental Instruction, Ana Mack

Electronic Theses and Dissertations

This study examined differences in academic performance and self-regulated learning based on levels of student participation in Supplemental Instruction (SI) sessions in two introductory undergraduate biology and chemistry courses offered at University of Central Florida in the Spring 2006 semester. The sample consisted of 282 students enrolled in the biology class and 451 students enrolled in chemistry. Academic performance was measured using students' final course grades and rates of withdrawal from the courses. The self-regulated learning constructs of motivation, cognition, metacognition, and resource management were measured using the Motivated Strategies for Learning Questionnaire (MSLQ). Relationships between students' gender and ethnic …

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Additive Lithography Fabrication And Integration Of Micro Optics, Mahesh Pitchumani Jan 2006

Additive Lithography Fabrication And Integration Of Micro Optics, Mahesh Pitchumani

Electronic Theses and Dissertations

Optical elements are the fundamental components in photonic systems and are used to transform an input optical beam into a desired beam profile or to couple the input beam into waveguides, fibers, or other optical systems or devices. Macroscopic optical elements are easily fabricated using grinding and polishing techniques, but few methods exist for inexpensive fabrication of micro optical elements. In this work we present an innovative technique termed Additive Lithography that makes use of binary masks and controlled partial exposures to sculpt photoresist into the desired optical surface relief profile. We explore various masking schemes for fabricating a variety …

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Up-Conversion In Rare-Earth Doped Micro-Particles Applied To New Emissive 2d Dislays, Anne Milliez Jan 2006

Up-Conversion In Rare-Earth Doped Micro-Particles Applied To New Emissive 2d Dislays, Anne Milliez

Electronic Theses and Dissertations

Up-conversion (UC) in rare-earth co-doped fluorides to convert diode laser light in the near infrared to red, green and blue visible light is applied to make possible high performance emissive displays. The infrared-to-visible UC in the materials we study is a sequential form of non-linear two photon absorption in which a strong absorbing constituent absorbs two low energy photons and transfers this energy to another constituent which emits visible light. Some of the UC emitters' most appealing characteristics for displays are: a wide color gamut with very saturated colors, very high brightness operation without damage to the emitters, long lifetimes …

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A Study Of Florida Public Elementary School Principals' Job Satisfaction Following The Implementation Of Florida's A+ System For Grading Schools, Robert Paswaters Jan 2006

A Study Of Florida Public Elementary School Principals' Job Satisfaction Following The Implementation Of Florida's A+ System For Grading Schools, Robert Paswaters

Electronic Theses and Dissertations

The problem of this study was to examine the impact of Florida's A+ program of accountability on elementary principal job satisfaction. Specifically, the study was conducted to determine the relationship between a school's grade and principal job satisfaction. Of primary interest was the extent to which school accountability impacted principal satisfaction with the facets of Work on Present Job, Pay, Opportunities for Promotion, Supervision, People on the Present Job, and the job as a whole. The instruments used, the Job Descriptive Index (JDI) and Job in General (JIG) were provided through the JDI Research Office housed at Bowling Green State …

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A Comparison Of Marriage Education And Brief Couples Counseling, Tina Livingston Jan 2006

A Comparison Of Marriage Education And Brief Couples Counseling, Tina Livingston

Electronic Theses and Dissertations

This study investigated marital adjustment for couples participating in one of two treatment groups; the Brief Integrative Couples Counseling model(Young & Long, 1998, 2007); and the PREPARE/ENRICH Empowering Couples marriage education weekend workshop (Olson & Olson,2000). This study examined the following research questions: Do couples show a different level of marital adjustment following Brief Integrative Couples Counseling compared to those who receive a marriage education treatment?; Do couples show greater marital adjustment following Brief Integrative Couples Counseling compared to those who participated in a Marriage Education weekend workshop treatment over time? This article presents an exploration of mean marital adjustment …

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Investigation Of The Impact Of Video-Based Anchored Instruction On The Implementation Of Inclusive Practices By Students With Learning Disabilities, Christopher O'Brien Jan 2006

Investigation Of The Impact Of Video-Based Anchored Instruction On The Implementation Of Inclusive Practices By Students With Learning Disabilities, Christopher O'Brien

Electronic Theses and Dissertations

For several years emerging trends in special education services have favored inclusion for students with disabilities. Concurrent to this evolution of philosophy in special education has been the advent of what could be considered inclusive instructional practices--those methods that aid in the successful inclusion of students with disabilities. These inclusive practices include co-teaching, cooperative learning, peer-mediated instruction, positive behavioral support, embedded learning strategies, and content-enhancements (Ehren, Lenz, & Deshler, 2005; King-Sears, 1997). As inclusive placements become an increasingly common standard of practice, particularly for students with learning disabilities, the need to assist general educators in establishing inclusive classrooms becomes a …

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The Effects Of The 5e Learning Cycle Model On Students' Understanding Of Force And Motion Concepts, Meghann Campbell Jan 2006

The Effects Of The 5e Learning Cycle Model On Students' Understanding Of Force And Motion Concepts, Meghann Campbell

Electronic Theses and Dissertations

As advocated by the National Research Council [NRC] (1996) and the American Association for the Advancement of Science [AAAS] (1989), a change in the manner in which science is taught must be recognized at a national level and also embraced at a level that is reflected in every science teacher's classroom. With these ideas set forth as a guide for change,this study investigated the fifth grade students' understanding of force and motion concepts as they engaged in inquiry-based science investigations through the use of the 5E Learning Cycle. The researcher's journey through this process was also a focus of the …

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National Merit Finalists At The University Of Central Florida-Trends, Attrition, And Retention 1997-2005, Jill Norburn Jan 2006

National Merit Finalists At The University Of Central Florida-Trends, Attrition, And Retention 1997-2005, Jill Norburn

Electronic Theses and Dissertations

The purpose of this study was to examine the trends, attrition and retention rates of National Merit Finalists at the University of Central Florida between the years of 1997 to 2005. This study was intended to provide information for higher education practitioners, faculty, and administrators to help them better understand the expectations and current trends of National Merit Finalists. The problem was to determine how to increase recruitment and retention while decreasing the attrition rates of these highly desirable students. The importance of this study includes identifying trends that may aid in future recruitment efforts for National Merit Finalists; finding …

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The Effects Of Hands-On Instructional Strategies On Fourth Grade Students' Attitudes And Performance In Mathematics, Lindsey Hosack Jan 2006

The Effects Of Hands-On Instructional Strategies On Fourth Grade Students' Attitudes And Performance In Mathematics, Lindsey Hosack

Electronic Theses and Dissertations

This study summarizes research conducted in a fourth grade classroom in a suburban elementary school in the fall of 2005. This study investigated the practice of using hands-on instructional strategies, enhanced with technology, to improve students' attitudes and performance in mathematics. The classroom teacher supplemented conventional mathematics instruction with hands-on activities. Attitudinal data were collected using a pre- and post anxiety survey as well as journal writing assignments and student interviews. Performance data was collected using evaluative assessments. Results of this study showed a positive change in students' attitude towards mathematics. Student performance gains were recorded and analyzed throughout the …

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A Case Study Of Four Years Documenting The Changes In The Process Of Self-Reporting Academic Program Plans Alongside The Perceptions Of Program Coordinators, Kedar Kulkarni Jan 2006

A Case Study Of Four Years Documenting The Changes In The Process Of Self-Reporting Academic Program Plans Alongside The Perceptions Of Program Coordinators, Kedar Kulkarni

Electronic Theses and Dissertations

Major Advisors: Suzanne Martin, Ph.D., Laura Blasi, Ph.D. Universities in the United States of America are faced with numerous challenges concerning quality assurance such as the quest for Continuous Quality Improvement. Implementation of technology has been a priority of many developing institutions of higher education. A large metropolitan institution of higher education has put into practice a technology based, on-line program quality assessment system, for its academic and administrative programs. This dissertation was a study of the changes reported over four years, 2001-2005, within ten initial teacher preparation undergraduate programs at the College of Education at this institution. Using a …

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Synchronization In Advanced Optical Communications, Inwoong Kim Jan 2006

Synchronization In Advanced Optical Communications, Inwoong Kim

Electronic Theses and Dissertations

The objective of this dissertation is to generate high power ultrashort optical pulses from an all-semiconductor mode-locked laser system. The limitations of semiconductor optical amplifier in high energy, ultrashort pulse amplification are reviewed. A method to overcome the fundamental limit of small stored energy inside semiconductor optical amplifier called "eXtreme Chirped Pulse Amplification (X-CPA)" is proposed and studied theoretically and experimentally. The key benefits of the concept of X-CPA are addressed. Based on theoretical and experimental study, an all-semiconductor mode-locked X-CPA system consisting of a mode-locked master oscillator, an optical pulse pre-stretcher, a semiconductor optical amplifier (SOA) pulse picker, an …

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Application Of The Empirical Likelihood Method In Proportional Hazards Model, Bin He Jan 2006

Application Of The Empirical Likelihood Method In Proportional Hazards Model, Bin He

Electronic Theses and Dissertations

In survival analysis, proportional hazards model is the most commonly used and the Cox model is the most popular. These models are developed to facilitate statistical analysis frequently encountered in medical research or reliability studies. In analyzing real data sets, checking the validity of the model assumptions is a key component. However, the presence of complicated types of censoring such as double censoring and partly interval-censoring in survival data makes model assessment difficult, and the existing tests for goodness-of-fit do not have direct extension to these complicated types of censored data. In this work, we use empirical likelihood (Owen, 1988) …

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Direct Nonlinear Optics Measurements Of Raman Gain In Bulk Glasses And Estimates Of Fiber Performance, Robert Stegeman Jan 2006

Direct Nonlinear Optics Measurements Of Raman Gain In Bulk Glasses And Estimates Of Fiber Performance, Robert Stegeman

Electronic Theses and Dissertations

The need for more bandwidth in communications has stimulated the search for new fiberizable materials with properties superior to fused silica which is the current state-of-the-art. One of the key properties is Raman gain by which a pump beam amplifies a signal beam of longer wavelength. An apparatus capable of directly measuring the spectral dependence and absolute magnitude of the material Raman gain coefficient using nonlinear optics techniques has been built. Using radiation from a 1064 nm Nd:YAG laser as the pump and from a tunable Optical Parametric Generator and Amplifier as the signal, the Raman gain spectrum was measured …

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The Effects Of Gender In Elementary Science Groups, Melissa Parks Jan 2006

The Effects Of Gender In Elementary Science Groups, Melissa Parks

Electronic Theses and Dissertations

This action research study investigated the effects of gender on same and mixed gender elementary school science groups. Qualitative data for this study was collected using surveys, student focus groups, student journals, and teacher-researcher field notes and observations. Students in this study were eager to participate in science groups and demonstrated a positive attitude toward the study of science. Results also showed the types of interactions between boys and girls varied and those interactions affected their science attitude and participation. Recommendations were made for continued research to examine the long-term effects of gender groupings in the elementary science classroom.

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Antenna-Coupled Infrared And Millimeter-Wave Detectors: Fabrication, Measurement And Optimization, Charles Middleton Jan 2006

Antenna-Coupled Infrared And Millimeter-Wave Detectors: Fabrication, Measurement And Optimization, Charles Middleton

Electronic Theses and Dissertations

Antenna-coupled detectors provide uncooled, cost-effective solutions for infrared and millimeter-wave imaging. This work describes the design, fabrication, measurement, and optimization of several types of antenna-coupled detectors for LWIR (8 - 12 µm) and 94 GHz radiation. Two types of millimeter-wave antenna-coupled detectors were fabricated and tested: a slot antenna coupled to a bolometer, and a patch antenna coupled to a SiC Schottky diode. Electromagnetic modeling of the antennas helped guide the design of antennas with better impedance matching to the detectors. Schottky diodes are discussed as detectors for millimeter-wave and infrared radiation, with the goal of increasing the cutoff frequency …

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Integrated Inp Photonic Switches, Daniel May-Arrioja Jan 2006

Integrated Inp Photonic Switches, Daniel May-Arrioja

Electronic Theses and Dissertations

Photonic switches are becoming key components in advanced optical networks because of the large variety of applications that they can perform. One of the key advantages of photonic switches is that they redirect or convert light without having to make any optical to electronic conversions and vice versa, thus allowing networking functions to be lowered into the optical layer. InP-based switches are particularly attractive because of their small size, low electrical power consumption, and compatibility with integration of laser sources, photo-detectors, and electronic components. In this dissertation the development of integrated InP photonic switches using an area-selective zinc diffusion process …

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The Effect Of Different Presentation Formats Of Hypertext Annotations On Cognitive Load, Learning And Learner Control, Yuanming Yao Jan 2006

The Effect Of Different Presentation Formats Of Hypertext Annotations On Cognitive Load, Learning And Learner Control, Yuanming Yao

Electronic Theses and Dissertations

This dissertation study was intended to verify whether the positive effects of the roll-over annotation presentation format on reducing cognitive load and enhancing vocabulary and comprehension of 5th-grade children (Morrison, 2004) can be extended to college students' learning from a web-delivered text. In order to answer this research question, relevant constructs, such as cognitive load, learner control and learning, have been examined in this experimental study of 149 undergraduate students in a state university at College of Education. No single effect of annotation presentation format on cognitive load was found, but an interaction effect on cognitive load was revealed between …

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Teacher Retention In Brevard County, Florida K-12 Schools, Kenneth Winn Jan 2006

Teacher Retention In Brevard County, Florida K-12 Schools, Kenneth Winn

Electronic Theses and Dissertations

This descriptive study was designed to determine the extent to which selected self-reported practical and professional factors of teaching influenced teacher job satisfaction and retention within the K-12 public education system. The population of the study was 1321 certified teachers from a large Central Florida school district. The researcher developed the survey instrument based on the constructs of teaching known for motivating teachers to remain within the public school setting (Brunetti, 2001; Farkas, Johnson, & Folena, 2005). The researcher's survey was based on the studies of Perie (1997), Brunetti (2001), and Gary (2002). The researcher personally distributed 1321 surveys, respondent …

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A Comparison Of Ordinary Least Squares, Weighted Least Squares, And Other Procedures When Testing For The Equality Of Regression, Patrick J. Rosopa Jan 2006

A Comparison Of Ordinary Least Squares, Weighted Least Squares, And Other Procedures When Testing For The Equality Of Regression, Patrick J. Rosopa

Electronic Theses and Dissertations

When testing for the equality of regression slopes based on ordinary least squares (OLS) estimation, extant research has shown that the standard F performs poorly when the critical assumption of homoscedasticity is violated, resulting in increased Type I error rates and reduced statistical power (Box, 1954; DeShon & Alexander, 1996; Wilcox, 1997). Overton (2001) recommended weighted least squares estimation, demonstrating that it outperformed OLS and performed comparably to various statistical approximations. However, Overton's method was limited to two groups. In this study, a generalization of Overton's method is described. Then, using a Monte Carlo simulation, its performance was compared to …

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The Analysis Of The Relationship Between Learning Styles And The Learners' Knowledge Acquisition And Reactions Through The Online Case Study, Rui Zeng Jan 2006

The Analysis Of The Relationship Between Learning Styles And The Learners' Knowledge Acquisition And Reactions Through The Online Case Study, Rui Zeng

Electronic Theses and Dissertations

The purpose of this study was to examine the relationship between learning styles and student performance on a pre and post test, using an online case study, while also documenting their reactions to the case study. The case studies used in this research contained different storylines that showed multiple perspectives of case scenarios, giving students more choices to see what may happen in real school situations. Working with undergraduate students (N = 138) from the College of Education at a southeastern university, the researcher examined how students learned and responded to an online case study relative to their learning styles. …

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Effect Of Germanium Doping On Erbium Sensitization In The Erbium Doped Silicon Rich Silica Material System, Forrest Ruhge Jan 2006

Effect Of Germanium Doping On Erbium Sensitization In The Erbium Doped Silicon Rich Silica Material System, Forrest Ruhge

Electronic Theses and Dissertations

The continued size reduction in electronic integrated circuits has lead to a demand for on-chip high-bandwidth and low loss communication channels. Optical interconnects are considered an essential addition to the silicon electronics platform. A major challenge in the field of integrated Si photonics is the development of cost effective silicon compatible light sources. This thesis investigates the sensitization of group IV doped silica films emitting at 1.535μm for applications as silicon compatible light sources. Thin erbium-doped silica films containing excess silicon and germanium were deposited using a multi-gun sputter system. The composition of the deposited materials was verified by Rutherford …

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External Cavity Multiwavelength Semiconductor Mode-Locked Laser Gain Dynamics, Luis Archundia-Berra Jan 2006

External Cavity Multiwavelength Semiconductor Mode-Locked Laser Gain Dynamics, Luis Archundia-Berra

Electronic Theses and Dissertations

External cavity semiconductor mode-locked lasers can produce pulses of a few picoseconds. The pulses from these lasers are inherently chirped with a predominant linear chirp component that can be compensated resulting in sub-picosecond pulses. External cavity semiconductor mode-locked lasers can be configured as multiwavelength pulse sources and are good candidates for time and wavelength division multiplexing applications. The gain medium in external cavity semiconductor mode-locked lasers is a semiconductor optical amplifier (SOA), and passive and hybrid mode-locked operation are achieved by the introduction of a saturable absorber (SA) in the laser cavity. Pump-probe techniques were used to measure the intracavity …

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Police Organizational Performance In The State Of Florida:Confirmatory Analysis Of The Relationship Of The Environment And Design Structure To Performance, Jeffrey Goltz Jan 2006

Police Organizational Performance In The State Of Florida:Confirmatory Analysis Of The Relationship Of The Environment And Design Structure To Performance, Jeffrey Goltz

Electronic Theses and Dissertations

To date, police organizations have not been rigorously analyzed by organizational scholars and most analysis of these organizations has been captured through a single construct. The purpose of this study is to develop confirmatory police organizational analysis by validating a multi-dimensional conceptual framework that explains the relationships among three constructs: environmental constraints, the design structures of police organizations, and organizational performance indicators. The modeling is deeply rooted in contingency theory, and the influence of isomorphism and institutional theory on the covariance structure model are investigated. One hundred and thirteen local police organizations from the State of Florida are included in …

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Three-Photon Absorption Process In Organic Dyes Enhanced By Surface Plasmon Resonance, Ion Cohanoschi Jan 2006

Three-Photon Absorption Process In Organic Dyes Enhanced By Surface Plasmon Resonance, Ion Cohanoschi

Electronic Theses and Dissertations

Multi-photon absorption processes have received significant attention from the scientific community during the last decade, mainly because of their potential applications in optical limiting, data storage and biomedical fields. Perhaps, one of the most investigated processes studied so far has been two-photon absorption (2PA). These investigations have resulted in successful applications in all the fields mentioned above. However, 2PA present some limitations in the biomedical field when pumping at typical 2PA wavelengths. In order to overcome these limitations, three-photon absorption (3PA) process has been proposed. However, 3PA in organic molecules has a disadvantage, typical values of σ3' are small (10-81 …

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Effects Of Atmospheric Turbulence On The Propagation Of Flattened Gaussian Optical Beams, Doris Cowan Jan 2006

Effects Of Atmospheric Turbulence On The Propagation Of Flattened Gaussian Optical Beams, Doris Cowan

Electronic Theses and Dissertations

In an attempt to mitigate the effects of the atmosphere on the coherence of an optical (laser) beam, interest has recently been shown in changing the beam shape to determine if a different power distribution at the transmitter will reduce the effects of the random fluctuations in the refractive index. Here, a model is developed for the field of a flattened Gaussian beam as it propagates through atmospheric turbulence, and the resulting effects upon the scintillation of the beam and upon beam wander are determined. A comparison of these results is made with the like effects on a standard TEM00 …

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High Birefringence And Low Viscosity Liquid Crystals, Chien-Hui Wen Jan 2006

High Birefringence And Low Viscosity Liquid Crystals, Chien-Hui Wen

Electronic Theses and Dissertations

In this dissertation, liquid crystal (LC) materials and devices are investigated in order to meet the challenges for photonics and displays applications. We have studied three kinds of liquid crystal materials: positive dielectric anisotropic LCs, negative dielectric anisotropic LCs, and dual- frequency LCs. For the positive dielectric anisotropic LCs, we have developed some high birefringence isothiocyanato tolane LC compounds with birefringence ~0.4, and super high birefringence isothiocyanato biphenyl-bistolane LC compounds with birefringence as high as ~0.7. Moreover, we have studied the photostability of several high birefringence LC compounds, mixtures, and LC alignment layers in order to determine the failure mechanism …

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The Exchangeable Multinomial Modeling In Correlated Data, Yuanyuan Ding Jan 2006

The Exchangeable Multinomial Modeling In Correlated Data, Yuanyuan Ding

Electronic Theses and Dissertations

No abstract provided.

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