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2006

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Holographic Patterning Of Polymer Dispersed Liquid Crystal Materials For Diffractive Optical Elements, Robert Allan Ramsey Dec 2006

Holographic Patterning Of Polymer Dispersed Liquid Crystal Materials For Diffractive Optical Elements, Robert Allan Ramsey

Physics Dissertations - Archive

Liquid crystals are a soft condensed matter phase that share properties with both isotropic liquids and crystalline solids. Composite materials formed from both low molecular weight liquid crystals and polymers are of both fundamental and technological importance. One method for preparing dispersions of polymers and liquid crystals is polymerization-induced phase separation. Photo-polymerization induced phase separation utilizes a mixture of a liquid crystal and a photo curable polymer contained between two indium tin-oxide (ITO) coated glass substrates. Irradiation of the homogeneous pre-polymer mixture initiates polymerization, which in turn induces a phase separation between the polymer and liquid crystal. Holographically patterned polymer …


Gridfields: Model-Driven Data Transformation In The Physical Sciences, Bill Howe Dec 2006

Gridfields: Model-Driven Data Transformation In The Physical Sciences, Bill Howe

Dissertations and Theses

Scientists' ability to generate and store simulation results is outpacing their ability to analyze them via ad hoc programs. We observe that these programs exhibit an algebraic structure that can be used to facilitate reasoning and improve performance. In this dissertation, we present a formal data model that exposes this algebraic structure, then implement the model, evaluate it, and use it to express, optimize, and reason about data transformations in a variety of scientific domains.

Simulation results are defined over a logical grid structure that allows a continuous domain to be represented discretely in the computer. Existing approaches for manipulating …


An Energy Efficient Mac-Phy Approach To Support Distributed Source Coding In Wireless Sensor Network, Wei Wang, Dongming Peng, Honggang Wang, Hamid Sharif, Beata J. Wysocki, Tadeusz A. Wysocki Dec 2006

An Energy Efficient Mac-Phy Approach To Support Distributed Source Coding In Wireless Sensor Network, Wei Wang, Dongming Peng, Honggang Wang, Hamid Sharif, Beata J. Wysocki, Tadeusz A. Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

Distributed Source Coding (DSC) based signal processing applications are ideal candidates for multirate transmissions in Wireless Sensor Network (WSN). In this paper, we propose a novel MAC-PHY approach in WSN to achieve energy efficiency using multirate desirable for the DSC based signal processing applications. Our approach is different from the common multirate research in link adaptation, the focus of which is to increase throughput based on rate adaptation derived from variable channel conditions. In the proposed approach, the redundant and inefficient communications are eliminated, yielding significant improvement of energy efficiency in WSN. Here, the minimum desirable transmission power can be …


Modulational Instability In A Layered Kerr Medium: Theory And Experiment, Martin Centurion, Mason A. Porter, Ye Pu, P. G. Kevrekidis, D. J. Frantzeskakis, Demetri Psaltis Dec 2006

Modulational Instability In A Layered Kerr Medium: Theory And Experiment, Martin Centurion, Mason A. Porter, Ye Pu, P. G. Kevrekidis, D. J. Frantzeskakis, Demetri Psaltis

Martin Centurion Publications

We present the first experimental investigation of modulational instability in a layered Kerr medium. The particularly interesting and appealing feature of our configuration, consisting of alternating glass-air layers, is the piecewise-constant nature of the material properties, which allows a theoretical linear stability analysis leading to a Kronig-Penney equation whose forbidden bands correspond to the modulationally unstable regimes. We find very good quantitative agreement between theoretical, numerical, and experimental diagnostics of the modulational instability. Because of the periodicity in the evolution variable arising from the layered medium, there are multiple instability regions rather than just one as in a uniform medium.


Spatial And Temporal Variation In Cores From Lake Titicaca, Bolivia/Peru During The Last 13,000 Years, Sherilyn C. Fritz, P. A. Baker, P. Tapia, J. Garland Dec 2006

Spatial And Temporal Variation In Cores From Lake Titicaca, Bolivia/Peru During The Last 13,000 Years, Sherilyn C. Fritz, P. A. Baker, P. Tapia, J. Garland

Department of Earth and Atmospheric Sciences: Faculty Publications

We compared the stratigraphy of sediment cores that span the last 13,000 yrs from three sites in the main basin of Lake Titicaca, Boliva/Peru as indicators of regional paleoclimate. The cores show similar patterns of change after ~6,400 calendar yrs before present (cal yr BP) but differ before that time. Site NE98-PC2, which is near the Rio Illave and its delta, shows differences in diatom species composition and in calcium carbonate concentrations relative to cores from the other two sites, particularly during times of inferred high precipitation. In contrast, the carbon isotopic stratigraphy of the three sites is relatively similar. …


Expression And Characterization Of Hyperthermophilic Aqujfex Pyrophilus Flagellin Protein In Mesophilic Bacterial Systems, Srivani V. Mukkamala Dec 2006

Expression And Characterization Of Hyperthermophilic Aqujfex Pyrophilus Flagellin Protein In Mesophilic Bacterial Systems, Srivani V. Mukkamala

Masters Theses

The structural protein flagellin, FlaA derived from hyperthermophilic Aquifex pyrophilus, a rod shaped eubacterial species that grows near hydrothermal vents at an optimum growth temperature of 85 °C forms elongated thermostable flagella nanotubes. FlaA was successfully over-expressed for the first time using pET28c plasmid in E. coli BL21 cells at 37 °C. The protein was isolated from inclusion bodies that were solubilized by alkaline pH, refolded by dialysis and purified by chromatographic techniques. The FlaA was characterized by fluorescence, light scattering and circular dichroism. The FlaA was not in the correct folded form to form flagella as efforts to …


Investigation Of Knock In Gaseous Fuels In The Presence Of Diluents, Roshan Ashok Rodrigues Dec 2006

Investigation Of Knock In Gaseous Fuels In The Presence Of Diluents, Roshan Ashok Rodrigues

Masters Theses

Recent energy security and environmental concerns have prompted growing interest into utilization of alternative fuels such as, natural gas and landfill gas. These gaseous fuels contain significant amount of diluents in the fuel composition, such as carbon dioxide, nitrogen, water vapor and other trace gases, which vary by geographical location. Successful engine operation is limited by a phenomenon called "knock", which occurs due to auto-ignition of the end gas ahead of the flame front, and therefore, needs to be investigated with the utilization of these gaseous fuels.

The present contribution discusses the experimental set-up, procedure and results of the investigation …


Clique Percolation For Finding Naturally Cohesive And Overlapping Document Clusters, Wei Gao, Kam-Fai Wong, Yunqing Xia, Ruifeng Xu Dec 2006

Clique Percolation For Finding Naturally Cohesive And Overlapping Document Clusters, Wei Gao, Kam-Fai Wong, Yunqing Xia, Ruifeng Xu

Research Collection School Of Computing and Information Systems

Techniques for find document clusters mostly depend on models that impose strong explicit and/or implicit priori assumptions. As a consequence, the clustering effects tend to be unnatural and stray away from the intrinsic grouping natures of a document collection. We apply a novel graph-theoretic technique called Clique Percolation Method (CPM) for document clustering. In this method, a process of enumerating highly cohesive maximal document cliques is performed in a random graph, where those strongly adjacent cliques are mingled to form naturally overlapping clusters. Our clustering results can unveil the inherent structural connections of the underlying data. Experiments show that CPM …


Set-Based Cascading Approaches For Magnetic Resonance (Mr) Image Segmentation (Scamis), Jiang Liu, Tze-Yun Leong, Kin Ban Chee, Boon Pin Tan, Borys Shuter, Shih Chang Wang Dec 2006

Set-Based Cascading Approaches For Magnetic Resonance (Mr) Image Segmentation (Scamis), Jiang Liu, Tze-Yun Leong, Kin Ban Chee, Boon Pin Tan, Borys Shuter, Shih Chang Wang

Research Collection School Of Computing and Information Systems

This paper introduces Set-based Cascading Approach for Medical Image Segmentation (SCAMIS), a new methodology for segmentation of medical imaging by integrating a number of algorithms. Existing approaches typically adopt the pipeline methodology. Although these methods provide promising results, the results generated are still susceptible to over-segmentation and leaking. In our methodology, we describe how set operations can be utilized to better overcome these problems. To evaluate the effectiveness of this approach, Magnetic Resonance Images taken from a teaching hospital research programme have been utilised, to reflect the real world quality needed for testing in patient datasets. A comparison between the …


Towards Effective Content-Based Music Retrieval With Multiple Acoustic Feature Combination, Jialie Shen, John Shepherd, Ann H. H. Ngu Dec 2006

Towards Effective Content-Based Music Retrieval With Multiple Acoustic Feature Combination, Jialie Shen, John Shepherd, Ann H. H. Ngu

Research Collection School Of Computing and Information Systems

In this paper, we present a new approach to constructing music descriptors to support efficient content-based music retrieval and classification. The system applies multiple musical properties combined with a hybrid architecture based on principal component analysis (PCA) and a multilayer perceptron neural network. This architecture enables straightforward incorporation of multiple musical feature vectors, based on properties such as timbral texture, pitch, and rhythm structure, into a single low-dimensioned vector that is more effective for classification than the larger individual feature vectors. The use of supervised training enables incorporation of human musical perception that further enhances the classification process. We compare …


Measuring Qualities Of Articles Contributed By Online Communities, Ee Peng Lim, Ba-Quy Vuong, Hady W. Lauw, Aixin Sun Dec 2006

Measuring Qualities Of Articles Contributed By Online Communities, Ee Peng Lim, Ba-Quy Vuong, Hady W. Lauw, Aixin Sun

Research Collection School Of Computing and Information Systems

Using open source Web editing software (e.g., wiki), online community users can now easily edit, review and publish articles collaboratively. While much useful knowledge can be derived from these articles, content users and critics are often concerned about their qualities. In this paper, we develop two models, namely basic model and peer review model, for measuring the qualities of these articles and the authorities of their contributors. We represent collaboratively edited articles and their contributors in a bipartite graph. While the basic model measures an article's quality using both the authorities of contributors and the amount of contribution from each …


Supply Chain Information Sharing In A Macro Prediction Market, Zhiling Guo, Fang Fang, Andrew B. Whinston Dec 2006

Supply Chain Information Sharing In A Macro Prediction Market, Zhiling Guo, Fang Fang, Andrew B. Whinston

Research Collection School Of Computing and Information Systems

This paper aims to address supply chain partners' incentives for information sharing from an information systems design perspective. Specifically, we consider a supply chain characterized by N geographically distributed retailers who order a homogeneous product from one manufacturer. Each retailer's demand risk consists of two parts: a systematic risk part that affects all retailers and an idiosyncratic risk part that only has a local effect. We propose a macro prediction market to effectively elicit and aggregate useful information about systematic demand risk. We show that such information can be used to achieve accurate demand forecast sharing and better channel coordination …


Rapid Identification Of Column Heterogeneity, Bing Tian Dai, Nick Koudas, Beng Chin Ooi, Divesh Srivastava, Suresh Venkatasubramanian Dec 2006

Rapid Identification Of Column Heterogeneity, Bing Tian Dai, Nick Koudas, Beng Chin Ooi, Divesh Srivastava, Suresh Venkatasubramanian

Research Collection School Of Computing and Information Systems

No abstract provided.


Online Advertising By The Comparison Challenge Approach, Jae Wong Lee, Jae Kyu Lee Dec 2006

Online Advertising By The Comparison Challenge Approach, Jae Wong Lee, Jae Kyu Lee

Research Collection School Of Computing and Information Systems

To enhance the effectiveness of online comparisons from a manufacturer's point of view, we develop a framework for the comparison challenge approach. To develop the comparison challenge framework, we analyze 12 factors that determine the characteristics of comparison and propose models of valuable comparison challenges using the CompareMe and CompareThem strategies. We demonstrate the approaches with the example of PC selection. To help plan the comparison challenges, we formulate a mathematical programming model that maximizes the total value of comparison under the constraints of comparison opportunity and budgetary limitation. The model is applied to eight comparison scenarios, and its performance …


An Experimental Study On U-Commerce Adoption: Impact Of Personalization And Privacy Concerns, H. Sheng, Fiona Fui-Hoon Nah, Keng Siau Dec 2006

An Experimental Study On U-Commerce Adoption: Impact Of Personalization And Privacy Concerns, H. Sheng, Fiona Fui-Hoon Nah, Keng Siau

Research Collection School Of Computing and Information Systems

Ubiquitous commerce (u-commerce) represents "anytime, anywhere" commerce. U-commerce can provide a high level of personalization, which can bring significant benefits to customers. However, privacy is a major concern to customers and an obstacle to the adoption of u-commerce. This research examines how personalization and context can impact customers' privacy concerns as well as intention to adopt u-commerce applications. As u-commerce is new and emerging, we used the scenario-based approach to operationalize personalization and context in an experimental study. The experimental results show that the effects of personalization on customers' privacy concerns and adoption intention are situation dependent.


Identifying Difficulties In Learning Uml, Keng Siau, Poi-Peng Loo Dec 2006

Identifying Difficulties In Learning Uml, Keng Siau, Poi-Peng Loo

Research Collection School Of Computing and Information Systems

Despite its recognition as a standard object-oriented modeling language, Unified Modeling Language (UML) has been criticized for such deficiencies as semantic inconsistencies, vagueness, and conflicting notations. the relationship between these deficiencies and the difficulties in the learning process is the focus of this study. A concept mapping technique is used to unveil the learning difficulties and suggestions for alleviating them are provided.


Lsuhsc Facilities Biweekly Update: December 2006, Lsuhsc Property And Facilities Management Dec 2006

Lsuhsc Facilities Biweekly Update: December 2006, Lsuhsc Property And Facilities Management

LSUHSC Facilities Biweekly Updates: 2006

LSUHSC Facilities Biweekly Updates from December 8 and 22, 2006.

These updates describe damage and a timeline of repairs at the LSU Health Sciences Center - New Orleans campus due to Hurricane Katrina which made landfall August 29, 2005.


Lsuhsc Facilities Daily Update: December 2006, Lsuhsc Property And Facilities Management Dec 2006

Lsuhsc Facilities Daily Update: December 2006, Lsuhsc Property And Facilities Management

LSUHSC Facilities Daily Updates: 2006

LSUHSC Dailly Facilities Updates from December 2006.

These updates describe damage and a timeline of repairs at the LSU Health Sciences Center - New Orleans campus due to Hurricane Katrina which made landfall August 29, 2005.


Genetic Resolution Of The Enigmatic Lesser Antillean Distribution Of The Frog Leptodactylus Validus (Anura, Leptodactylidae), Keneth Yanek, W. R. Heyer, Rafael O. De Sá Dec 2006

Genetic Resolution Of The Enigmatic Lesser Antillean Distribution Of The Frog Leptodactylus Validus (Anura, Leptodactylidae), Keneth Yanek, W. R. Heyer, Rafael O. De Sá

Biology Faculty Publications

Leptodactylus validus has an unusual distribution, inhabiting Trinidad, Tobago, and the Lesser Antilles, but not the mainland of South America. This distribution is inconsistent with other distribution patterns observed for these islands. Although slight variation in adult morphology has been observed among the different island populations of L. validus, call data suggest the presence of a single species. Calls of L. pallidirostris from Venezuela and Brazil suggested that this taxon might be conspecific with L. validus. Sequence data from the 12S and 16S mt rDNA genes indicate that L. validus represents a single species throughout its distribution and is conspecific …


Moritz Busch's Die Mormonen And The Conversion Of Karl G. Maeser, A. Legrand Richards Dec 2006

Moritz Busch's Die Mormonen And The Conversion Of Karl G. Maeser, A. Legrand Richards

BYU Studies

Karl G. Maeser’s contributions to the education of nineteenth-century Latter-day Saints had a profound impact on the history of Mormonism, an impact that has reverberated to today. The narrative surrounding Maeser’s conversion has been told and retold for over a century now in the enculturation of students into Brigham Young University’s heritage. This essay seeks to better understand and contextualize the events surrounding Maeser’s conversion and, more specifically, to discuss the text that was most influential in his conversion—the less-than-friendly Die Mormonen by Moritz Busch (1821–99).


The Prairie Naturalist, Volume 38, 2006: Reviewers, Author Index, And Subject Index, Elmer J. Finck, Hilary Gillock Dec 2006

The Prairie Naturalist, Volume 38, 2006: Reviewers, Author Index, And Subject Index, Elmer J. Finck, Hilary Gillock

The Prairie Naturalist

The list of reviewers, author index, and subject index for volume 38 (2006) of The Prairie Naturalist published by the Great Plains Natural Science Society out of Fort Hays State University in Kansas, United States.


Amphibians And Reptiles In A Mixed-Grass Prairie In Northwestern North Dakota, Robert K. Murphy, Robert F. Danley, Patricia K. Moore Dec 2006

Amphibians And Reptiles In A Mixed-Grass Prairie In Northwestern North Dakota, Robert K. Murphy, Robert F. Danley, Patricia K. Moore

The Prairie Naturalist

There have been almost no surveys of herpetofauna at 109 km2 Lostwood National Wildlife Refuge (LNWR) or surrounding counties in northwestern North Dakota, an area possibly undergoing significant environmental change from fossil fuel extraction and use. We used 30 m drift fences to survey amphibian and reptile species in prairie-wetland transition zones at LNWR during mid-May to early-July in 1985 to 1987, and again in 1999 and 2000. We captured only four amphibian and two reptilian species and noted one other reptilian species incidental to our survey. Several species expected to occur in the area were not detected.


Recognizing, Digitizing, Advertising: Gnarp Efforts With Unique German Studies Materials, Richard Hacken Dec 2006

Recognizing, Digitizing, Advertising: Gnarp Efforts With Unique German Studies Materials, Richard Hacken

Faculty Publications

Presented in the Winter 2005-2006 issue of the Global Resources Newsletter, the German-North American Resources Partnership issue. GNARP's Digital Libraries Working Group (DLWG) is tooling up to act as a sounding board and clearinghouse for collaborative projects that provide access, and add value, to materials sought by scholars. The spectrum of the group's activities can be summed up in the three verbs: recognizing, digitizing, advertising.


The Eastern Echo, December 1, 2006, Eastern Michigan University Dec 2006

The Eastern Echo, December 1, 2006, Eastern Michigan University

EMU Student Newspaper: The Normal News & The Eastern Echo

No abstract provided.


December 2006 Commencement Program, Bowling Green State University Dec 2006

December 2006 Commencement Program, Bowling Green State University

Commencement Programs

No abstract provided.


Oviposition Preference And Larval Growth Rates Of Caligo Memnon (Nymphalidae: Brassolinae), December 2006, Emily Webb Dec 2006

Oviposition Preference And Larval Growth Rates Of Caligo Memnon (Nymphalidae: Brassolinae), December 2006, Emily Webb

Monteverde Institute: Tropical Ecology and Conservation

Caligo memnon caterpillars specialize on plants in three families, Heliconiaceae, Marantaceae, and Musaceea. These families are in the Order Zingiberales. Heliconiaceae and Marantaceae are native to the Neotropics, but Musaceae is an introduced family. I studied oviposition preference and larval performance of C. memnon on four host plants: Heliconia latispatha and Heliconia stricta (Heliconiacea), Calathea insignis (Marantaceae), and Musa acuminata (Musacea). Results showed that preferred host plants for oviposition did not correspond to the host plant that provided the fastest growth rate for caterpillars. Females preferred to oviposit on M. acuminata even though larval growth was lowest on this species, …


History Lessons: How Textboks From Around The World Portray U.S. History, By Dana Lindaman & Kyle Ward, Cheryl Healy Dec 2006

History Lessons: How Textboks From Around The World Portray U.S. History, By Dana Lindaman & Kyle Ward, Cheryl Healy

Journal of Catholic Education

No abstract provided.


Portrayal Of Mathematicians In Fictional Works, Daniel Dotson Dec 2006

Portrayal Of Mathematicians In Fictional Works, Daniel Dotson

CLCWeb: Comparative Literature and Culture

In his article "Portrayal of Mathematicians in Fictional Works," Daniel Dotson explores how people with mathematical abilities -- including mathematicians, mathematics teachers, mathematically-inclined youths, cryptographers, and more -- are portrayed in novels, films, television programs, and a play. A summary table of the characters gives a short description of each of them, the title of the work in which they appeared, and the format of the work. Characters were analyzed to see if they possessed any of ten personality traits: obsessive, having major mental health problems, withdrawn, brave, timid, socially inept, arrogant, uses math to escape reality, out of touch, …


Generating Paraphrases With Greater Variation Using Syntactic Phrases, Rebecca Diane Madsen Dec 2006

Generating Paraphrases With Greater Variation Using Syntactic Phrases, Rebecca Diane Madsen

Theses and Dissertations

Given a sentence, a paraphrase generation system produces a sentence that says the same thing but usually in a different way. The paraphrase generation problem can be formulated in the machine translation paradigm; instead of translation of English to a foreign language, the system translates an English sentence (for example) to another English sentence. Quirk et al. (2004) demonstrated this approach to generate almost 90% acceptable paraphrases. However, most of the sentences had little variation from the original input sentence. Leveraging syntactic information, this thesis project presents an approach that successfully generated more varied paraphrase sentences than the approach of …


Moving Object Tracking: Seeking Extensible Solutions, Jeremy Pack Dec 2006

Moving Object Tracking: Seeking Extensible Solutions, Jeremy Pack

Undergraduate Honors Capstone Projects

Moving object tracking is a difficult field with no "best" solution. The documents contained here detail software that was developed in order to perform tracking of objects that are in the line of sight of multiple cameras. Some of the software developed is already in use by the US Army Dugway Proving Ground. Other software represents prototype or early development code. This software was written by Jeremy Pack, who was the lead programmer, and Luke Andrew at the Space Dynamics Laboratory in Logan, Utah.