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2006

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Burrows Dug By Large Vertebrates Into Rain-Moistened Middle Jurassic Sand Dunes, David B. Loope Jan 2006

Burrows Dug By Large Vertebrates Into Rain-Moistened Middle Jurassic Sand Dunes, David B. Loope

Department of Earth and Atmospheric Sciences: Faculty Publications

In south-central Utah, eolian cross-strata of the Escalante Member of the Entrada Sandstone contain inclined, cylindrical burrows up to 63 cm in diameter and 305 cm long. Of the 14 large tunnels located during this study, 12 descend from second- and third-order bounding surfaces that formed on the lee slopes of large dune ridges, well above the water table. The tunnels are inclined 15°–22°; one tunnel ends in an expanded chamber. Eolian cross-strata fill proximal portions of four of the tunnels and indicate that after abandonment, sand drifts migrated as much as a meter into the open shafts. Structureless sand …

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The Earth All Around Us: Selected Building Stone In Lincoln, Nebraska. A Walking Tour, William J. Wayne Jan 2006

The Earth All Around Us: Selected Building Stone In Lincoln, Nebraska. A Walking Tour, William J. Wayne

Department of Earth and Atmospheric Sciences: Faculty Publications

Stone has been a primary building material for millennia. Cities, therefore, are treasure troves of earth materials. A wide variety of stones from many places are used for walls, as foundations to support entire buildings, as trim, and more recently as cladding (facing, an overlay). The Earth science teacher can find, in the limited space of an urban environment, a superb collection of stones with which to introduce students to these materials. The surfaces of stones on the outsides of buildings illustrate the durability and the vulnerability of each kind of stone to the local climate. And the history of …

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Understanding Farmers’ Forecast Use From Their Beliefs, Values, Social Norms, And Perceived Obstacles*, Q. Steven Hu, Lisa M. Pytlikzillig, Gary D. Lynne, Alan Tomkins, William J. Waltman, Michael J. Hayes, Kenneth Hubbard, Ikrom Artikov, Stacey Hoffman, Donald A. Wilhite Jan 2006

Understanding Farmers’ Forecast Use From Their Beliefs, Values, Social Norms, And Perceived Obstacles*, Q. Steven Hu, Lisa M. Pytlikzillig, Gary D. Lynne, Alan Tomkins, William J. Waltman, Michael J. Hayes, Kenneth Hubbard, Ikrom Artikov, Stacey Hoffman, Donald A. Wilhite

Department of Earth and Atmospheric Sciences: Faculty Publications

Although the accuracy of weather and climate forecasts is continuously improving and new information retrieved from climate data is adding to the understanding of climate variation, use of the forecasts and climate information by farmers in farming decisions has changed little. This lack of change may result from knowledge barriers and psychological, social, and economic factors that undermine farmer motivation to use forecasts and climate information. According to the theory of planned behavior (TPB), the motivation to use forecasts may arise from personal attitudes, social norms, and perceived control or ability to use forecasts in specific decisions. These attributes are …

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Imse Alumni Survey Of Abet Program Educational Objectives, Paul Savory Jan 2006

Imse Alumni Survey Of Abet Program Educational Objectives, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

This report showcases the results of the Department of Industrial and Management System Engieering's survey of alumni regarding our updated ABET Program Educational Objectives. The Program Educational Objectives represent the expected characteristics of industrial engineering graduates within three to five years of receiving a Bachelor of Science degree in Industrial and Management Systems Engineering from the University of Nebraska-Lincoln. A total of 76 responses were received. The alumni survey responses indicate strong agreement and approval for the new Program Educational Objectives. The associated comments will be used by the IMSE faculty to future refine the course curriculum to ensure that …

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A Template-Based Data Specification Framework For Modeling Physical Security Systems, Ashu Guru, Paul Savory Jan 2006

A Template-Based Data Specification Framework For Modeling Physical Security Systems, Ashu Guru, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

Simulation studies often fail to provide any useful results due to its success being highly dependent on the skills of the analyst to understand a system and then correctly identify all the required data parameters and dependent variables. This paper describes a template-based framework to help identify and specify the components and data parameters for developing models of physical security systems. The layered framework consists of fifteen templates built on top of fourteen data primitives representing 119 data parameters. The modeling framework has been programmed as an internet-based web application and is simulation language independent. The usefulness of the framework …

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E(Fg)2: A New Fixed-Grid Shape Optimization Method, Florin Bobaru Ph.D., Srinivas Rachakonda Jan 2006

E(Fg)2: A New Fixed-Grid Shape Optimization Method, Florin Bobaru Ph.D., Srinivas Rachakonda

Department of Engineering Mechanics: Faculty Publications

We propose a shape optimization method over a fixed grid. Nodes at the intersection with the fixed grid lines track the domain’s boundary. These “floating” boundary nodes are the only ones that can move/appear/disappear in the optimization process. The element-free Galerkin (EFG) method, used for the analysis problem, provides a simple way to create these nodes. The fixed grid (FG) defines integration cells for EFG method. We project the physical domain onto the FG and numerical integration is performed over partially cut cells. The integration procedure converges quadratically. The performance of the method is shown with examples from shape optimization …

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On-Off Frequency-Shift Keying For Wideband Fading Channels, Mustafa Cenk Gursoy, H. Vincent Poor, Sergio Verdu Jan 2006

On-Off Frequency-Shift Keying For Wideband Fading Channels, Mustafa Cenk Gursoy, H. Vincent Poor, Sergio Verdu

Department of Electrical and Computer Engineering: Faculty Publications

M-ary on-off frequency-shift keying (OOFSK) is a digital modulation format in which M-ary FSK signaling is overlaid on on/off keying. This paper investigates the potential of this modulation format in the context of wideband fading channels. First, it is assumed that the receiver uses energy detection for the reception of OOFSK signals. Capacity expressions are obtained for the cases in which the receiver has perfect and imperfect fading side information. Power efficiency is investigated when the transmitter is subject to a peak-to-average power ratio (PAR) limitation or a peak power limitation. It is shown that under a PAR limitation, it …

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The Transcriptome Of Human Oocytes, Arif Murat Kocabas, Javier Crosby, Pablo J. Ross, Hasan H. Otu, Zeki Beyhan, Handan Can, Wai-Leong Tam, Guilherme J. M. Rosa, Robert G. Halgren, Bing Lim, Emilio Fernandez, Jose Bernardo Cibelli Jan 2006

The Transcriptome Of Human Oocytes, Arif Murat Kocabas, Javier Crosby, Pablo J. Ross, Hasan H. Otu, Zeki Beyhan, Handan Can, Wai-Leong Tam, Guilherme J. M. Rosa, Robert G. Halgren, Bing Lim, Emilio Fernandez, Jose Bernardo Cibelli

Department of Electrical and Computer Engineering: Faculty Publications

The identification of genes and deduced pathways from the mature human oocyte can help us better understand oogenesis, folliculogenesis, fertilization, and embryonic development. Human metaphase II oocytes were used within minutes after removal from the ovary, and its transcriptome was compared with a reference sample consisting of a mixture of total RNA from 10 different normal human tissues not including the ovary. RNA amplification was performed by using a unique protocol. Affymetrix Human Genome U133 Plus 2.0 GeneChip arrays were used for hybridizations. Compared with reference samples, there were 5,331 transcripts significantly up-regulated and 7,074 transcripts significantly down-regulated in the …

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Energy-Constrained Quality Optimization For Secure Image Transmission In Wireless Sensor Networks, Wei Wang, Dongming Peng, Honggang Wang, Hamid Sharif, Hsiao-Hwa Chen Jan 2006

Energy-Constrained Quality Optimization For Secure Image Transmission In Wireless Sensor Networks, Wei Wang, Dongming Peng, Honggang Wang, Hamid Sharif, Hsiao-Hwa Chen

Department of Electrical and Computer Engineering: Faculty Publications

Resource allocation for multimedia selective encryption and energy efficient transmission has not been fully investigated in literature for wireless sensor networks (WSNs). In this article, we propose a new cross-layer approach to optimize selectively encrypted image transmission quality in WSNs with strict energy constraint. A new selective image encryption approach favorable for unequal error protection (UEP) is proposed, which reduces encryption overhead considerably by controlling the structure of image bitstreams. Also, a novel cross-layer UEP scheme based on cipher-plain-text diversity is studied. In this UEP scheme, resources are unequally and optimally allocated in the encrypted bitstream structure, including data position …

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Navigating Dangerous Deliberative Waters: Shallow Argument Pools, Group Polarization And Public Debate Pedagogy In Southeast Europe, Gordon R. Mitchell, Damien S. Pfister, Georgeta Bradatan, Dejan Colev, Tsvetelina Manolova, Gligor Mitkovski, Ivanichka Nestorova, Milena Ristic, Gentiana Sheshi Jan 2006

Navigating Dangerous Deliberative Waters: Shallow Argument Pools, Group Polarization And Public Debate Pedagogy In Southeast Europe, Gordon R. Mitchell, Damien S. Pfister, Georgeta Bradatan, Dejan Colev, Tsvetelina Manolova, Gligor Mitkovski, Ivanichka Nestorova, Milena Ristic, Gentiana Sheshi

Department of Communication Studies: Faculty Publications

An Albanian social movement called Mjaft ! serves as a synecdoche for wider trends unfolding in Southeast Europe, where student, driven public deliberation is enlivening the political landscape not only in Albania, but also in Bulgaria, Kosovo, Macedonia, Montenegro, Serbia, and Romania. What do these initiatives suggest about the political dynamics of linkages formed between academic debating groups and civil society organizations? Can public debate democratically energize South, east European citizenries? What general insight does this case study reveal about argumentation as applied critical practice? This paper explores these questions by drawing from collaborative research conducted by the authors under …

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Modeling Dual Polarization Wireless Fading Channels Using Quaternions, B. J. Wysocki, Tadeusz Wysocki, J. Seberry Jan 2006

Modeling Dual Polarization Wireless Fading Channels Using Quaternions, B. J. Wysocki, Tadeusz Wysocki, J. Seberry

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

In the letter we describe signal transmitted between two dual-polarized antennas using a quaternion notation. The channel can then be modeled by a single quaternion gain, instead of a matrix of four complex gains as it is done in a classical approach. The model is very useful as it allows for a simple accommodation of any polarization twist between the transmit and receive antennas, as well as, modeling random fading in both polarizations with or without cross-polar scattering.

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Deliberating Debate’S Digital Futures, Carly Woods, Matthew Brigham, Brent Heavner, Takuzo Konishi, John Rief, Brent Saindon, Gordon R. Mitchell Jan 2006

Deliberating Debate’S Digital Futures, Carly Woods, Matthew Brigham, Brent Heavner, Takuzo Konishi, John Rief, Brent Saindon, Gordon R. Mitchell

Department of Communication Studies: Faculty Publications

Human communities can use collective deliberation to make considered decisions regarding their relationship to technology. Such reflection is particularly warranted, because as sociologist Langdon Winner (1986) observes, "technological artifacts have politics" (p. 19). In other words, choices about technology carry political implications, because patterns of sociality are embedded within technical tools (McMillan and Hyde, 2000). Fortunately, Winner notes, "by far the greatest latitude of choice exists the very first time a particular instrument, system, or technique is introduced" (Winner 1986, p. 29). Winner's insight punctuates the salience and timeliness of this forum exchange, which comes at a moment when the …

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Spatial Distributions Of Perchloroethylene Reactive Transport Parameters In The Borden Aquifer, Richelle M. Allen-King, Dana Divine, Michel J. L. Robin, J. Richard Alldredge, David R. Gaylord Jan 2006

Spatial Distributions Of Perchloroethylene Reactive Transport Parameters In The Borden Aquifer, Richelle M. Allen-King, Dana Divine, Michel J. L. Robin, J. Richard Alldredge, David R. Gaylord

Conservation and Survey Division: Faculty and Staff Publications

We determined the descriptive statistical and spatial geostatistical properties of the perchloroethene ln Kd and the ln k of a 1.5 m thick by 10 m horizontal transect of the Borden aquifer near the location of the Stanford-Waterloo (SW) tracer experiment. The ln Kd distribution is not normal and is right skewed because of a few high values that occur localized in two regions of the transect. In contrast, the ln k data can be characterized by a normal distribution. A linear regression of ln Kd on ln k yields a statistically significant positive correlation, also shown …

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Wyclif’S Trinitarian And Christological Theology, Stephen E. Lahey Jan 2006

Wyclif’S Trinitarian And Christological Theology, Stephen E. Lahey

Department of Classics and Religious Studies: Faculty Publications

Anyone familiar with amateur photography can imagine standing in a darkroom, watching the slow resolution of a picture as it sits in its chemical bath. First the main outlines of the image emerge from a blank background, and only gradually do the details follow. Frequently the content of the picture is only recognizable when all the details are clear, when what appear as large, oddly shaped objects resolve into distinct, recognizable ones. Such is the case with understanding of Wyclif’s earlier, theological works. Without a familiarity with the details of fourteenth-century Oxford theology, its main players and positions, and their …

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Evaluating The Effectiveness Of Slicing For Model Reduction Of Concurrent Object-Oriented Programs, Matthew B. Dwyer, John Hatcliff, Matthew Hoosier, Venkatesh Ranganath, Robby, Todd Wallentine Jan 2006

Evaluating The Effectiveness Of Slicing For Model Reduction Of Concurrent Object-Oriented Programs, Matthew B. Dwyer, John Hatcliff, Matthew Hoosier, Venkatesh Ranganath, Robby, Todd Wallentine

School of Computing: Book Chapters

Model checking techniques have proven effective for checking a number of non-trivial concurrent object-oriented software systems. However, due to the high computational and memory costs, a variety of model reduction techniques are needed to overcome current limitations on applicability and scalability. Conventional wisdom holds that static program slicing can be an effective model reduction technique, yet anecdotal evidence is mixed, and there has been no work that has systematically studied the costs/benefits of slicing for model reduction in the context of model checking source code for realistic systems. In this paper, we present an overview of the sophisticated Indus program …

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A Maximum-Likelihood Approach To Symbolic Indirect Correlation, Ashutosh Joshi, George Nagy, Daniel Lopresti, Sharad C. Seth Jan 2006

A Maximum-Likelihood Approach To Symbolic Indirect Correlation, Ashutosh Joshi, George Nagy, Daniel Lopresti, Sharad C. Seth

School of Computing: Conference and Workshop Papers

Symbolic Indirect Correlation (SIC) is a nonparametric method that offers significant advantages for recognition of ordered unsegmented signals. A previously introduced formulation of SIC based on subgraph-isomorphism requires very large reference sets in the presence of noise. In this paper, we seek to address this issue by formulating SIC classification as a maximum likelihood problem. We present experimental evidence that demonstrates that this new approach is more robust for the problem of online handwriting recognition using noisy input.

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On Reoptimizing Multi-Class Classifiers, Kun Deng, Chris Bourke, Stephen Scott, Robert E. Schapire, N. V. Vinodchandran Jan 2006

On Reoptimizing Multi-Class Classifiers, Kun Deng, Chris Bourke, Stephen Scott, Robert E. Schapire, N. V. Vinodchandran

School of Computing: Technical Reports

Significant changes in the instance distribution or associated cost function of a learning problem require one to reoptimize a previously learned classifier to work under new conditions. We study the problem of reoptimizing a multi-class classifier based on its ROC hypersurface and a matrix describing the costs of each type of prediction error. For a binary classifier, it is straightforward to find an optimal operating point based on its ROC curve and the relative cost of true positive to false positive error. However, the corresponding multi-class problem (finding an optimal operating point based on a ROC hypersurface and cost matrix) …

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Practical And Predictive Bioinformatics Methods For The Identification Of Potentially Cross-Reactive Protein Matches, Richard E. Goodman Jan 2006

Practical And Predictive Bioinformatics Methods For The Identification Of Potentially Cross-Reactive Protein Matches, Richard E. Goodman

Department of Food Science and Technology: Faculty Publications

A bioinformatics comparison of proteins introduced into food crops through genetic engineering provides a mechanism to identify those proteins that may present an increased risk of allergic reactions for individuals with existing allergies. The goal is to identify proteins that are known to be allergens or are so similar to an allergen that they may induce allergic cross-reactions. Three comparative approaches have traditionally been used, or considered for safety evaluations. One identifies any short (6–8) amino acid segment of the protein that exactly matches a known allergen sequence. The second is an overall primary sequence comparison using Basic Local Alignment …

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Ecologically-Based Participatory Ipm In A Global Context: The Ipm Crsp Model, E. A. Heinrichs Jan 2006

Ecologically-Based Participatory Ipm In A Global Context: The Ipm Crsp Model, E. A. Heinrichs

Department of Entomology: Faculty Publications

The IPM CRSP develops and implements approaches to IPM that help raise the standard of living and improve the environment in countries around the world. The IPM CRSP model is based on (1) participatory IPM, (2) networking, (3) capacity/institution building, (4) res~h and. technology development and (5) technology ·transfer. Regional programs in Central Asia, East Africa, West Africa, Latin American/Caribbean, Eastern Europe, South Asia and Southeast Asia address problems of a specific region and the global themes, invasive species, information technology and databases, regional diagnostic laboratories, insect transmitted viruses, and impact assessments deal with universal issues. Major crop emphasis is …

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Modulation Of The Coma-Dependent Quorum Response In Bacillus Subtilis By Multiple Rap Proteins And Phr Peptides, Jennifer M. Auchtung, Catherine A. Lee, Alan D. Grossman Jan 2006

Modulation Of The Coma-Dependent Quorum Response In Bacillus Subtilis By Multiple Rap Proteins And Phr Peptides, Jennifer M. Auchtung, Catherine A. Lee, Alan D. Grossman

Department of Food Science and Technology: Faculty Publications

In Bacillus subtilis, extracellular peptide signaling regulates several biological processes. Secreted Phr signaling peptides are imported into the cell and act intracellularly to antagonize the activity of regulators known as Rap proteins. B. subtilis encodes several Rap proteins and Phr peptides, and the processes regulated by many of these Rap proteins and Phr peptides are unknown. We used DNA microarrays to characterize the roles that several rap-phr signaling modules play in regulating gene expression. We found that rapK-phrK regulates the expression of a number of genes activated by the response regulator ComA. ComA activates expression of genes involved in …

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Temperament And Language Skills As Predictors Of Teacher–Child Relationship Quality In Preschool, Kathleen Moritz Rudasill, Sara E. Rimm-Kaufman, Laura M. Justice, Khara Pence Jan 2006

Temperament And Language Skills As Predictors Of Teacher–Child Relationship Quality In Preschool, Kathleen Moritz Rudasill, Sara E. Rimm-Kaufman, Laura M. Justice, Khara Pence

Department of Educational Psychology: Faculty Publications

Current educational policy emphasizes “school readiness” of young children with a premium placed on preschool interventions that facilitate academic and social readiness for children who have had limited learning experiences prior to kindergarten (Rouse, Brooks–Gunn, & McLanahan, 2005). The teacher–child relationship is viewed as a critical mechanism for the effectiveness of interventions (Girolametto, Weitzman, & Greenberg, 2003; National Institute of Child Health and Human Development Early Child Care Research Network, 2003). The purpose of this study was to determine how children’s temperament and language skills predict teacher–child relationship quality. The sample consisted of 99 at-risk preschool students. Three findings emerged: …

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Museum Visitors’ Understanding Of Evolution, Amy N. Spiegel, E. Margaret Evans, Wendy Gram, Judy Diamond Jan 2006

Museum Visitors’ Understanding Of Evolution, Amy N. Spiegel, E. Margaret Evans, Wendy Gram, Judy Diamond

Department of Educational Psychology: Faculty Publications

In spite of overwhelming scientific evidence supporting evolution, a large percentage of the Ameri-can public does not understand or accept the fundamental principles of evolutionary theory. Museums have an important role in educating children and adults about evolution. This paper reviews recent museum visitor studies, which suggest that while visitors are interested in learning about and less likely to reject evolution than the general public, they tend to have a limited understanding of evolutionary concepts. A new conceptual framework, based on developmental research, indicates that visitors reason about evolution differently depending on the type of organism they are considering, applying …

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Optimization Of Multilayer Wear-Resistant Thin Films Using Finite Element Analysis On Stiff And Compliant Substrates, R. K. Lakkaraju, Florin Bobaru, S. L. Rohde Jan 2006

Optimization Of Multilayer Wear-Resistant Thin Films Using Finite Element Analysis On Stiff And Compliant Substrates, R. K. Lakkaraju, Florin Bobaru, S. L. Rohde

Department of Engineering Mechanics: Faculty Publications

Extensive research has been carried out by researchers on the growth and characterization of multilayer protective coatings, but the design of these coatings still remains largely empirical. In this regard, recent progress has been made in developing a design approach for optimizing a multilayer coating structure before deposition, which would help save time and material. In pursuit of an optimal design, finite element analysis using a plane strain Hertzian contact model was developed to investigate the stress/ strain behavior within the layers of the system. The present study looks to find the optimal thicknesses of individual layers in a multilayer …

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A Model For Predicting The Evolution Of Multiple Cracks On Multiple Length Scales In Viscoelastic Composites, David H. Allen, C. R. Searcy Jan 2006

A Model For Predicting The Evolution Of Multiple Cracks On Multiple Length Scales In Viscoelastic Composites, David H. Allen, C. R. Searcy

Department of Engineering Mechanics: Faculty Publications

A model is presented herein for predicting the evolution of numerous cracks on multiple length scales, the objective of such a model being to develop the capability to predict failure of structural components to perform their intended tasks. Such a capability would then be useful as a predictive tool for designing structural components so as not to fail, but rather to succeed in performing their intended tasks. The model developed herein is somewhat involved, being based in continuum mechanics and thermodynamics, but is nevertheless expected to be cost effective (wherever sufficient accuracy permits) when compared to more costly experimental means …

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Guide To Nebraska Map Resources, Sue Ann Gardner Jan 2006

Guide To Nebraska Map Resources, Sue Ann Gardner

University of Nebraska-Lincoln Libraries: Faculty Publications

Includes listings for Doane College, Midland Lutheran College, University of Nebraska-Kearney, American Historical Society of Germans from Russia, Lincoln City Libraries, Nebraska Department of Natural Resources, Nebraska Department of Roads, Nebraska Library Commission, Nebraska State Historical Society, University of Nebraska-Lincoln, Norfolk Public Library, Douglas County Historical Society Library, Omaha Public Library, and University of Nebraska-Omaha.

Information includes address, personnel, holdings, access, hours, geographic information systems, collection services, and physical facilities.

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Efficient Inverted Polymer Solar Cells, G. Li, C.-W. Chu, V. Shrotriya, Jinsong Huang, Y. Yang Jan 2006

Efficient Inverted Polymer Solar Cells, G. Li, C.-W. Chu, V. Shrotriya, Jinsong Huang, Y. Yang

Department of Mechanical and Materials Engineering: Faculty Publications

We investigate the effect of interfacial buffer layers—vanadium oxide (V2O5) and cesium carbonate (Cs2CO3)—on the performance of polymer solar cells based on regioregular poly-(3-hexylthiophene) and [6,6]-phenyl C60 butyric acid methyl ester blend. The polarity of solar cells can be controlled by the relative positions of these two interfacial layers. Efficient inverted polymer solar cells were fabricated with the structure of indium tin oxide (ITO)/Cs2CO3/polymer blend/vanadium oxide (V2O5)/aluminum (Al). Short-circuit current of 8.42 mA/cm2, open-circuit voltage of 0.56 V, and power conversion efficiency of …

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Improving The Power Efficiency Of White Light-Emitting Diode By Doping Electron Transport Material, Jinsong Huang, Wei-Jen Hou, Juo-Hao Li, Gang Li, Yang Yang Jan 2006

Improving The Power Efficiency Of White Light-Emitting Diode By Doping Electron Transport Material, Jinsong Huang, Wei-Jen Hou, Juo-Hao Li, Gang Li, Yang Yang

Department of Mechanical and Materials Engineering: Faculty Publications

Highly efficient white light emission was realized via the partial energy transfer from blue host polyfluorene (PF) to orange light emission dopant rubrene. A more balanced charge transport was achieved by adding an electron transport material, 2-(4-biphenylyl)-5-(4-tertbutylphenyl)-1,3,4-oxadiazole (PBD), into the PF-rubrene system to enhance the electron transportation. Efficiency improvement by as much as a factor of 2 has been observed through the addition of PBD. These devices can easily reach high luminance at low driving voltages, thus achieving high power efficiency at high luminance (14.8, 13.5, and 12.0 lm/W at the luminances of 1000, 2000, and 4000 cd/m2, …

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Piezoelectromagnetic Waves In A Ceramic Plate Between Two Ceramic Half-Spaces, S. N. Jiang, Q. Jiang, X. F. Li, S. H. Guo, H. G. Zhou, J. S. Chang Jan 2006

Piezoelectromagnetic Waves In A Ceramic Plate Between Two Ceramic Half-Spaces, S. N. Jiang, Q. Jiang, X. F. Li, S. H. Guo, H. G. Zhou, J. S. Chang

Department of Mechanical and Materials Engineering: Faculty Publications

We analyze the propagation of piezoelectromagnetic waves guided by a plate of polarized ceramics between two ceramic half-spaces. An exact dispersion relation is obtained, which reduces to a few known elastic, electromagnetic, and quasistatic piezoelectric wave solutions in the literature as special cases. Numerical solutions to the equation that determines the dispersion relation show the existence of guided waves. The results are useful for acoustic wave and microwave devices.

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Long-Distance Dispersal And Population Trends Of Moose In The Central United States, Justin D. Hoffman, Hugh H. Genoways, Jerry R. Choate Jan 2006

Long-Distance Dispersal And Population Trends Of Moose In The Central United States, Justin D. Hoffman, Hugh H. Genoways, Jerry R. Choate

University of Nebraska State Museum: Mammalogy Papers

Dispersal is a basic feature of the natural history of moose. Most information about moose dispersal pertains to short-distance movements because long-distance movements are uncommon and difficult to observe. Since the 1950s, moose populations have been increasing in Minnesota and North Dakota. This may have contributed to several long-distance dispersal events for moose that recently were reported in the central United States. These dispersal events provide an opportunity to investigate both the causes and the biological implications of this rare phenomenon. Herein, we review long-distance dispersal events based on information obtained from a variety of sources. Dispersal routes that could …

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Proximate And Landscape Factors Influence Grassland Bird Distributions, Mary Ann Cunningham, Douglas H. Johnson Jan 2006

Proximate And Landscape Factors Influence Grassland Bird Distributions, Mary Ann Cunningham, Douglas H. Johnson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Ecologists increasingly recognize that birds can respond to features well beyond their normal areas of activity, but little is known about the relative importance of landscapes and proximate factors or about the scales of landscapes that influence bird distributions. We examined the influences of tree cover at both proximate and landscape scales on grassland birds, a group of birds of high conservation concern, in the Sheyenne National Grassland in North Dakota, USA. The Grassland contains a diverse array of grassland and woodland habitats. We surveyed breeding birds on 2015 100 m long transect segments during 2002 and 2003. We modeled …

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