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2008

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A 20-Year Plan For Hunter/Angler Recruitment, Development And Retention In Nebraska, Mark Pinkerton, Ron Stave, Mick Jensen, James Ziebarth, Jerrod Burke, Lynn Berggren, George Hall, Kent Forney Jan 2008

A 20-Year Plan For Hunter/Angler Recruitment, Development And Retention In Nebraska, Mark Pinkerton, Ron Stave, Mick Jensen, James Ziebarth, Jerrod Burke, Lynn Berggren, George Hall, Kent Forney

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

Hunting and fishing are important parts of Nebraska’s rich heritage. These time-honored outdoor pursuits are important to overall lifestyle, well-being and natural resources of the citizens of Nebraska. The North American Model for Conservation was based primarily on the activism from our nation’s hunters and anglers. Their role helped develop and instill the seven basic premises of the model: Wildlife is to be held in public trust, there should be an elimination of market hunting, wildlife should be allocated by law, there should be hunting/angling opportunities for all citizens, wildlife should only be killed for legitimate reasons, wildlife should be …

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Providing Reliable Data Transport For Dynamic Event Sensing In Wireless Sensor Networks, Yuyan Xue, Byrav Ramamurthy, Yong Wang Jan 2008

Providing Reliable Data Transport For Dynamic Event Sensing In Wireless Sensor Networks, Yuyan Xue, Byrav Ramamurthy, Yong Wang

School of Computing: Conference and Workshop Papers

In this paper, we propose a Loss Tolerant Reliable (LTR) data transport mechanism for dynamic Event Sensing (LTRES) in WSNs. In LTRES, a reliable event sensing requirement at the transport layer is dynamically determined by the sink. A distributed source rate adaptation mechanism is designed, incorporating a loss rate based lightweight congestion control mechanism, to regulate the data traffic injected into the network so that the reliability requirement can be satisfied. An equation based fair rate control algorithm is used to improve the fairness among the LTRES flows sharing the congestion path. The performance evaluations show that LTRES can provide …

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A Key Management Protocol For Wireless Sensor Networks With Multiple Base Stations, Yong Wang, Byrav Ramamurthy, Yuyan Xue Jan 2008

A Key Management Protocol For Wireless Sensor Networks With Multiple Base Stations, Yong Wang, Byrav Ramamurthy, Yuyan Xue

School of Computing: Conference and Workshop Papers

Most of the proposed key management protocols for wireless sensor networks (WSNs) in the literature assume that a single base station is used and that the base station is trustworthy. However, there are applications in which multiple base stations are used and the security of the base stations must be considered. This paper investigates a key management protocol in wireless sensor networks which include multiple base stations. We consider the situations in which both the base stations and the sensor nodes can be compromised. The proposed key management protocol, mKeying, includes two schemes, a key distribution scheme, mKeyDist, supporting multiple …

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Predicting Accurate And Actionable Static Analysis Warnings: An Experimental Approach, Joseph Ronald Ruthruff, John Penix, J. David Morgenthaler, Sebastian Elbaum, Gregg Rothermel Jan 2008

Predicting Accurate And Actionable Static Analysis Warnings: An Experimental Approach, Joseph Ronald Ruthruff, John Penix, J. David Morgenthaler, Sebastian Elbaum, Gregg Rothermel

School of Computing: Conference and Workshop Papers

Static analysis tools report software defects that may or may not be detected by other verification methods. Two challenges complicating the adoption of these tools are spurious false positive warnings and legitimate warnings that are not acted on. This paper reports automated support to help address these challenges using logistic regression models that predict the foregoing types of warnings from signals in the warnings and implicated code. Because examining many potential signaling factors in large software development settings can be expensive, we use a screening methodology to quickly discard factors with low predictive power and cost-effectively build predictive models. Our …

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Design Of A Wireless Vision Sensor For Object Tracking In Wireless Vision Sensor Networks, Mauricio Casarest, Mehmet C. Vuran, Senem Velipasalar Jan 2008

Design Of A Wireless Vision Sensor For Object Tracking In Wireless Vision Sensor Networks, Mauricio Casarest, Mehmet C. Vuran, Senem Velipasalar

School of Computing: Conference and Workshop Papers

The integration of CMOS cameras with embedded processors and wireless communication devices has enabled the development of distributed wireless vision systems. Wireless Vision Sensor Networks (WVSNs), which consist of wirelessly connected embedded systems with vision and sensing capabilities, provide wide variety of application areas that have not been possible to realize with the wall-powered vision systems with wired links or scalar-data based wireless sensor networks. In this paper, the design of a middleware for a wireless vision sensor node is presented for the realization of WVSNs. The implemented wireless vision sensor node is tested through a simple vision application to …

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Remembering And Forgetting Black Power In Mississippi Burning, Kristen Hoerl Jan 2008

Remembering And Forgetting Black Power In Mississippi Burning, Kristen Hoerl

Department of Communication Studies: Faculty Publications

Although critics are correct to point out that Mississippi Burning did not faithfully depict historical events surrounding the real-life disappearances of [civil rights activists] Chaney, Schwerner, and Goodman, I argue that these criticisms overlook some of the ways in which the film advances the cause of racial justice. On a formal level, Mississippi Burning evokes the struggles experienced by members of the Black Power movement, a social movement that emerged on the heels of civil rights. Looking at the film in the context of this movement, I argue that Mississippi Burning is a homology for the Black Power movement. Barry …

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Performance Analysis Of Multi-Hop Ieee 802.11 Dcf Backhaul Networks, Puttipong Mahasukhon, Hamid Sharif, Michael Hempel, Ting Zhou, Wei Wang, Tadeusz Wysocki Jan 2008

Performance Analysis Of Multi-Hop Ieee 802.11 Dcf Backhaul Networks, Puttipong Mahasukhon, Hamid Sharif, Michael Hempel, Ting Zhou, Wei Wang, Tadeusz Wysocki

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

Because of the wide deployment of 802.11 equipments in the past decade, current applications are not limited anymore to only single Access Points (AP) deployments for indoor usage, but have been extended to multi-hop networks to fulfill the need of high speed connectivity in mobile environments, where the analysis of multi-hop networks is extremely complicated. The behavior of an AP is dependent not only on its neighbors’ behavior, but also on the behavior of other hidden nodes. In this paper, we provide an accurate and verified multi-hop wireless backhaul analysis for performance of IEEE 802.11 DCF in terms of the …

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Network Coding For Wdm All-Optical Multicast, Eric D. Manley, Jitender S. Deogun, Lisong Xu, Dennis R. Alexander Jan 2008

Network Coding For Wdm All-Optical Multicast, Eric D. Manley, Jitender S. Deogun, Lisong Xu, Dennis R. Alexander

School of Computing: Technical Reports

Network coding has become a useful means for achieving efficient multicast, and the optical community has started to examine its application to optical networks. However, a number of challenges, including limited processing capability and coarse bandwidth granularity, need to be overcome before network coding can be effectively used in optical networks. In this paper, we address some of these problems. We consider the problem of finding efficient routes to use with coding, and we study the effectiveness of using network coding for optical-layer dedicated protection of multicast traffic. We also propose architectures for all-optical circuits capable of performing the processing …

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Cooperative Communication In Space-Time-Frequency Coded Mb-Ofdm Uwb, L. C. Tran, A. Mertins, Tadeusz Wysocki Jan 2008

Cooperative Communication In Space-Time-Frequency Coded Mb-Ofdm Uwb, L. C. Tran, A. Mertins, Tadeusz Wysocki

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

Though cooperative communication has been intensively examined for general wireless systems, such as mobile and ad-hoc networks, it has been almost unexplored in the case of Space-Time-Frequency Coded Multi-band OFDM Ultra-Wideband (STFC MB-OFDM UWB). This paper proposes a framework of cooperative communication in such systems where nodes are equipped with only one antenna. Simulation results show that cooperative communication might, in some cases, provide better error performance than non-cooperative communication without any additional transmission power.

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Considering Operational Issues For Multiagent Conceptual Inferencing In A Distributed Information Retrieval Application, Leen-Kiat Soh Jan 2008

Considering Operational Issues For Multiagent Conceptual Inferencing In A Distributed Information Retrieval Application, Leen-Kiat Soh

School of Computing: Faculty Publications

Our system, based on a multiagent framework called collaborative understanding of distributed knowledge (CUDK), is designed with the overall goal of balancing agents’ conceptual learning and task accomplishment. The tradeoff between the two is that while conceptual learning allows an agent to improve its own concept base, it could be counter-productive: conceptual learning is time consuming and requires processing resources necessary for the agent to accomplish its tasks. In our current phase of research, we investigate the roles of resource and knowledge constraints, environmental factors (such as the frequency of queries), and learning mechanisms in a CUDK-based distributed information retrieval …

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I-Minds: A Multiagent System For Intelligent Computer- Supported Collaborative Learning And Classroom Management, Leen-Kiat Soh, Nobel Khandaker, Hong Jiang Jan 2008

I-Minds: A Multiagent System For Intelligent Computer- Supported Collaborative Learning And Classroom Management, Leen-Kiat Soh, Nobel Khandaker, Hong Jiang

School of Computing: Faculty Publications

I-MINDS provides a computer-supported collaborative learning (CSCL) infrastructure and environment for learners in synchronous learning and classroom management applications for instructors, for large classroom or distance education situations. For supporting the instructor, I-MINDS includes a teacher agent. The teacher agent allows the instructor to interact with students, manage Q&A sessions, administer quizzes, post evaluations, form groups and monitor individual and group performances. For computer-supported collaborative learning, I-MINDS, which stands for Intelligent Multiagent Infrastructure for Distributed Systems in Education, provides a student agent for each student. Each student agent monitors and models its user and carries out group formation with other …

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Partial Forwarding Scheme For Dynamic Window Resizing In Live P2p Streaming Systems, Zhipeng Ouyang, Lisong Xu, Byrav Ramamurthy Jan 2008

Partial Forwarding Scheme For Dynamic Window Resizing In Live P2p Streaming Systems, Zhipeng Ouyang, Lisong Xu, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

Peer-to-peer (P2P) streaming systems, in which individual nodes or peers operated by ordinary Internet users collaborate to serve video streams, have recently aroused considerable interest in both academia and industry. An important problem in P2P streaming systems is how to reduce their consumed bandwidth, which is a major concern of Internet service providers. Our work is motivated by the fact that a user may dynamically change the size of a window displaying a video stream according to his/her personal choice, a scenario we refer to as dynamic window resizing. In this paper, we propose a scheme called the Partial Forwarding …

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Computation Of A Face Attractiveness Index Based On Neoclassical Canons, Symmetry, And Golden Ratios, Kendra Schmid, David Marx, Ashok Samal Jan 2008

Computation Of A Face Attractiveness Index Based On Neoclassical Canons, Symmetry, And Golden Ratios, Kendra Schmid, David Marx, Ashok Samal

School of Computing: Faculty Publications

Analysis of attractiveness of faces has long been a topic of research. Literature has identified many different factors that can be related to attractiveness. In this research we analyze the role of symmetry, neoclassical canons, and golden ratio in the determination of attractiveness of a face. We focus on the geometry of a face and use actual faces for our analysis. We find there are some differences in the criteria used by males and females to determine attractiveness. The model we have developed to predict the attractiveness of a face using its geometry is accurate with low residual errors.

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Food Insecurity And Maternal Depression In Rural, Low-Income Families: A Longitudinal Investigation, Catherine Huddleston-Casas, Richard Charnigo, Leigh Ann Simmons Jan 2008

Food Insecurity And Maternal Depression In Rural, Low-Income Families: A Longitudinal Investigation, Catherine Huddleston-Casas, Richard Charnigo, Leigh Ann Simmons

Nebraska Center for Research on Children, Youth, Families, and Schools: Faculty Publications

Objective: The purpose of the present study was to examine the relationship between household food insecurity and maternal depression in a rural sample to determine whether food insecurity predicted mothers’ depression over time or vice versa.

Design: The study employed a prospective design using three waves of data from ‘Rural Families Speak’, a multi-state study of low-income rural families in the USA. Food insecurity was measured using the Core Food Security Module and depression was measured using the Center for Epidemiologic Studies–Depression Scale. A structural equation model was fit to the data using the AMOS software package.

Setting: Sixteen states …

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Addressing Research Gaps In The Intersection Between Homophobia And Bullying, Dorothy L. Espelage, Susan M. Swearer Napolitano Jan 2008

Addressing Research Gaps In The Intersection Between Homophobia And Bullying, Dorothy L. Espelage, Susan M. Swearer Napolitano

Department of Educational Psychology: Faculty Publications

Bullying, aggression, and peer victimization among adolescents are significant public health concerns. Recent research has demonstrated that bullying and peer victimization sometimes include homophobic epithets directed at heterosexual and lesbian, gay, bisexual, and transgender (LGBT) youth. It appears that being at the receiving end of homophobic banter generally contributes to worse outcomes among youth. This article highlights methodological issues in conducting research with LGBT youth, and stresses the importance of using theoretically and empirically supported definitions, including youth who are sexually questioning, focusing on multiple social and cultural contexts, and examining how support networks serve as buffering agents with regard …

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Anabolic Androgenic Steroids: Use And Perceived Use In Non-Athlete College Students, Joseph M. Berning, Kent J. Adams, Mark Debeliso, Bryant A. Stamford, Ian Newman Jan 2008

Anabolic Androgenic Steroids: Use And Perceived Use In Non-Athlete College Students, Joseph M. Berning, Kent J. Adams, Mark Debeliso, Bryant A. Stamford, Ian Newman

Department of Educational Psychology: Faculty Publications

Objective: The authors investigated the use and perceived use of anabolic androgenic steroids (AAS) among nonathlete college students. Participants: The authors surveyed a sample of 485 nonathlete college students at a major metropolitan university. Methods: They administered a survey on use and perceived use of AAS to the students. Results: Forty-two participants (9%) reported using AAS (37 men, 5 women). Seniors were the most likely to use AAS (36%), and freshman the least likely (7%). Thirty-four percent of nonusers and 41% of users indicated they knew between 1 and 5 AAS users. Of the total sample, 36% perceived that 5% …

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Atlantic And Pacific Sst Influences On Medieval Drought In North America Simulated By The Community Atmospheric Model, Song Feng, Robert Oglesby, Clinton M. Rowe, David B. Loope, Qi Hu Jan 2008

Atlantic And Pacific Sst Influences On Medieval Drought In North America Simulated By The Community Atmospheric Model, Song Feng, Robert Oglesby, Clinton M. Rowe, David B. Loope, Qi Hu

Department of Earth and Atmospheric Sciences: Faculty Publications

Severe drought is arguably one of the greatest recurring natural disasters that strikes North America. A synthesis of multiproxy data shows that North America was in the grip of a severe centennial-scale drought during medieval times (800–1300 AD). In this study, the Community Atmospheric Model (CAM) is used to investigate the role of sea surface temperature (SST) anomalies from the North Atlantic and the tropical Pacific Ocean on this megadrought. These anomalies are obtained from proxy reconstructions of SST. Four model experiments with prescribed SST anomalies in the tropical Pacific and/or North Atlantic Ocean were made. The CAM results captured …

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Life In A Temperate Polar Sea: A Unique Taphonomic Window On The Structure Of A Late Cretaceous Arctic Marine Ecosystem, Karen Chin, John Bloch, Arthur Sweet, Justin Tweet, Jaelyn Eberle, Stephen Cumbaa, Jakub Witowski, David M. Harwood Jan 2008

Life In A Temperate Polar Sea: A Unique Taphonomic Window On The Structure Of A Late Cretaceous Arctic Marine Ecosystem, Karen Chin, John Bloch, Arthur Sweet, Justin Tweet, Jaelyn Eberle, Stephen Cumbaa, Jakub Witowski, David M. Harwood

Department of Earth and Atmospheric Sciences: Faculty Publications

As the earth faces a warming climate, the rock record reminds us that comparable climatic scenarios have occurred before. In the Late Cretaceous, Arctic marine organisms were not subject to frigid temperatures but still contended with seasonal extremes in photoperiod. Here, we describe an unusual fossil assemblage from Devon Island, Arctic Canada, that offers a snapshot of a ca 75 MYR ago marine paleoecosystem adapted to such conditions. Thick siliceous biogenic sediments and glaucony sands reveal remarkably persistent high primary productivity along a high-latitude Late Cretaceous coastline. Abundant fossil feces demonstrate that this planktonic bounty supported benthic invertebrates and large, …

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Elevated Primary Productivity Of Calcareous Nannoplankton Associated With Ocean Anxoic Event 1b During The Aptian/Albian Transition (Early Cretaceous), Emily L. Browning, David K. Watkins Jan 2008

Elevated Primary Productivity Of Calcareous Nannoplankton Associated With Ocean Anxoic Event 1b During The Aptian/Albian Transition (Early Cretaceous), Emily L. Browning, David K. Watkins

Department of Earth and Atmospheric Sciences: Faculty Publications

Previous isotopic investigations of Aptian/Albian oceanic anoxic event (OAE) 1b from the western North Atlantic (Blake Nose) posited that increased sea surface temperatures and decreased salinity led to stratification of the upper water column, resulting in lowered dissolved oxygen and enhanced organic matter preservation. We examined calcareous nannofossils from the same site in the western North Atlantic (Blake Nose) to evaluate changes in surface water conditions prior to, during, and after the Aptian/Albian OAE1b. The results of our analysis conflict somewhat with the previous interpretation that OAE1b at Blake Nose was linked to water column stratification. The signal from calcareous …

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Chloride And The Environmental Isotopes As The Indicators Of The Groundwater Recharge In The Gobi Desert, Northwest China, J. Z. Ma, Z. Ding, John B. Gates, Y. Su Jan 2008

Chloride And The Environmental Isotopes As The Indicators Of The Groundwater Recharge In The Gobi Desert, Northwest China, J. Z. Ma, Z. Ding, John B. Gates, Y. Su

Department of Earth and Atmospheric Sciences: Faculty Publications

The long term recharge in Gobi Desert from Hexi Corridor to Inner Mongolia Plateau was estimated to Be 1 mm year-1 by using the chloride mass balance method from one unsaturated zone profile, which shows that no effective modern recharge is taking place. A good rainfall database from Zhangye provides definition of the stable isotopic composition of modern rainfall. The signature of groundwater from the late Pleistocene differs markedly from that of the Holocene, shown clearly by the compositions of -10.5‰ δ18O as compared with values of -7‰ at the present day. It is apparent that the …

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Seismic Facies And Stratigraphy Of The Cenozoic Succession In Mcmurdo Sound, Antarctica: Implications For Tectonic, Climatic And Glacial History, Christopher R. Fielding, J. Whittaker, Stuart A. Henrys, T. J. Wilson, T. R. Naish Jan 2008

Seismic Facies And Stratigraphy Of The Cenozoic Succession In Mcmurdo Sound, Antarctica: Implications For Tectonic, Climatic And Glacial History, Christopher R. Fielding, J. Whittaker, Stuart A. Henrys, T. J. Wilson, T. R. Naish

Department of Earth and Atmospheric Sciences: Faculty Publications

A new stratigraphic model is presented for the evolution of the Cenozoic Victoria Land Basin of the West Antarctic Rift, based on integration of seismic reflection and drilling data. The Early Rift phase (?latest Eocene to Early Oligocene) comprises wedges of strata confined by early extensional faults, and which contain seismic facies consistent with drainage via coarse-grained fans and deltas into discrete, actively subsiding grabens and half-grabens. The Main Rift phase (Early Oligocene to Early Miocene) comprises a lens of strata that thickens symmetrically from the basin margins into a central depocenter, and in which stratal events pass continuously over …

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Wind Through The Buffalo Grass: A Lakota Story Cycle, Paul A. Johnsgard Jan 2008

Wind Through The Buffalo Grass: A Lakota Story Cycle, Paul A. Johnsgard

Paul Johnsgard Collection

Wind Through the Buffalo Grass: A Lakota Story Cycle is a narrative history of the Pine Ridge Lakota tribe of South Dakota, following its history from 1850 to the present day through historical events and through the stories of four fictional Lakota children, each related by descent and separated from one another by two generations. The ecology of the Pine Ridge region, especially its mammalian and avian wildlife, is woven into the stories of the children. Illustrated by the author, the book indudes drawings of Pine Ridge wildlife, regional maps, and Native American pictorial art. Appendices indude a listing of …

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Holocene Multidecadal- To Millennial-Scale Hydrologic Variability On The South American Altiplano, Erick Ekdahl, Sherilyn C. Fritz, Paul A. Baker, Catherine Rigsby, Kirstin Coley Jan 2008

Holocene Multidecadal- To Millennial-Scale Hydrologic Variability On The South American Altiplano, Erick Ekdahl, Sherilyn C. Fritz, Paul A. Baker, Catherine Rigsby, Kirstin Coley

Department of Earth and Atmospheric Sciences: Faculty Publications

Precipitation on the South American Altiplano varies at a range of temporal scales. A long-term secular increase in moisture availability from the early/mid Holocene to the present, driven by increasing summer insolation resulting from precessional changes in the Earth’s orbit, has been documented in earlier studies. However, higher frequency Holocene variability is not yet understood. Here we present high-resolution diatom assemblage data from two small Altiplano lakes, Lago Lagunillas and Lago Umayo, indicating changes in effective moisture in the southern tropical Andes at decadal, centennial and millennial timescales throughout the mid to late Holocene. A strong millennial-scale component, similar in …

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Reef Foraminifera As Bioindicators Of Coral Reef Health: Low Isles Reef, Northern Great Barrier Reef, Australia, Jonathan D. Schueth, Tracy D. Frank Jan 2008

Reef Foraminifera As Bioindicators Of Coral Reef Health: Low Isles Reef, Northern Great Barrier Reef, Australia, Jonathan D. Schueth, Tracy D. Frank

Department of Earth and Atmospheric Sciences: Faculty Publications

Declining water quality associated with changes in land use over the past century is considered a significant environmental threat to the health of coral platforms of the Great Barrier Reef, Australia, in particular for those situated in nearshore areas of the wet tropics. Of these reefs, perhaps the most well known is Low Isles Reef, which has been studied since 1928. Decline in scleractinian coral cover and increased abundances of soft-bodied corals and macroalgae since the 1950’s have led researchers to speculate that the reef is being affected by increased nutrient and sediment fluxes from nearby rivers. The Foraminifera in …

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Stratigraphic Imprint Of The Late Paleozoic Ice Age In Eastern Australia: A Record Of Alternating Glacial And Nonglacial Climate Regime, Christopher R. Fielding, Tracy D. Frank, Lauren P. Birgenheier, Michael C. Rygel, Andrew T. Jones, John Roberts Jan 2008

Stratigraphic Imprint Of The Late Paleozoic Ice Age In Eastern Australia: A Record Of Alternating Glacial And Nonglacial Climate Regime, Christopher R. Fielding, Tracy D. Frank, Lauren P. Birgenheier, Michael C. Rygel, Andrew T. Jones, John Roberts

Department of Earth and Atmospheric Sciences: Faculty Publications

Stratigraphic and sedimentological data from New South Wales and Queensland, eastern Australia, indicate that the Late Paleozoic Ice Age comprised at least eight discrete glacial intervals (each 1–8 Ma in duration, here termed “glaciations”), separated by nonglacial intervals of comparable duration. These events spanned an interval from mid-Carboniferous (c. 327 Ma) to the early Late Permian (c. 260 Ma), and illustrate a pattern of increasing climatic austerity and increasingly widespread glacial ice from initial onset until an acme in the late Early Permian, followed by an opposite trend towards the final demise of glaciation in the Late Permian. The alternating …

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Simulations With Elaborated Worked Example Modeling: Beneficial Effects On Schema Acquisition, Debra K. Meier, Karl J. Reinhard, David O. Carter, David W. Brooks Jan 2008

Simulations With Elaborated Worked Example Modeling: Beneficial Effects On Schema Acquisition, Debra K. Meier, Karl J. Reinhard, David O. Carter, David W. Brooks

Department of Entomology: Faculty Publications

Worked examples have been effective in enhancing learning outcomes, especially with novice learners. Most of this research has been conducted in laboratory settings. This study examined the impact of embedding elaborated worked example modeling in a computer simulation practice activity on learning achievement among 39 undergraduate students within a classroom environment. The students from one introductory forensic science course were randomly assigned to one of two groups that worked through computer-based simulations containing worked example modeling conditions presented in varied order. The computer software administered the modeled simulations, prior knowledge test, pretest, posttests, and a second domain test. Findings from …

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An Observational Analysis And Evaluation Of Land Surface Model Accuracy In The Nebraska Sand Hills, David B. Radell, Clinton M. Rowe Jan 2008

An Observational Analysis And Evaluation Of Land Surface Model Accuracy In The Nebraska Sand Hills, David B. Radell, Clinton M. Rowe

Department of Earth and Atmospheric Sciences: Faculty Publications

In this study, the influence of subsurface water on the energy budget components of three locations with heterogeneous land surfaces in the Nebraska Sand Hills are examined through observations and use of the Noah land surface model (LSM). Observations of the four primary components of the surface energy budget are compared for a wet interdunal meadow valley, a dry interdunal valley, and a dunal upland location. With similar atmospheric forcing at each site, it was determined that differences in the partitioning of the mean diurnal net radiation (Rnet) existed among the three locations due to the influence …

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The Pulsation Modes Of The Pre-White Dwarf Pg 1159-035, Jörge E.S. Costa, Matt A. Wood, Thomas J. Ahrens Jan 2008

The Pulsation Modes Of The Pre-White Dwarf Pg 1159-035, Jörge E.S. Costa, Matt A. Wood, Thomas J. Ahrens

Aerospace, Physics, and Space Science Faculty Publications

Context. PG 1159-035 , a pre-white dwarf with Teff ≃ 140 000 K, is the prototype of both two classes: the PG 1159 spectroscopic class and the DOV pulsating class. Previous studies of PG 1159-035 photometric data obtained with the Whole Earth Telescope (WET) showed a rich frequency spectrum allowing the identification of 122 pulsation modes. Analyzing the periods of pulsation, it is possible to measure the stellar mass, the rotational period and the inclination of the rotation axis, to estimate an upper limit for the magnetic field, and even to obtain information about the inner stratification of the star. …

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Study Of The Solar Anisotropy Of Cosmic Ray Primaries Of About 200 Gev Energy With The L3+C Muon Detector, G Baksay, L Baksay, K Dehmelt, M Hohlmann, Z Szillasi, I Vodopianov, The L3 Collaboration Jan 2008

Study Of The Solar Anisotropy Of Cosmic Ray Primaries Of About 200 Gev Energy With The L3+C Muon Detector, G Baksay, L Baksay, K Dehmelt, M Hohlmann, Z Szillasi, I Vodopianov, The L3 Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Context. Primary cosmic rays experience multiple deflections in the non-uniform galactic and heliospheric magnetic fields which may generate anisotropies. Aims. A study of anisotropies in the energy range between 100 and 500 GeV is performed. This energy range is not yet well explored. Methods. The L3 detector at the CERN electron-positron collider, LEP, is used for a study of the angular distribution of atmospheric muons with energies above 20 GeV. This distribution is used to investigate the isotropy of the time-dependent intensity of the primary cosmic-ray flux with a Fourier analysis. Results. A small deviation from isotropy at energies around …

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Quantitative Constraints On The Transport Properties Of Hot Partonic Matter From Semi-Inclusive Single High Transverse Momentum Pion Suppression In Au+Au Collisions At √Snn = 200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration Jan 2008

Quantitative Constraints On The Transport Properties Of Hot Partonic Matter From Semi-Inclusive Single High Transverse Momentum Pion Suppression In Au+Au Collisions At √Snn = 200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

The PHENIX experiment has measured the suppression of semi-inclusive single high-transverse-momentum π0's in Au+Au collisions at √sNN = 200 GeV. The present understanding of this suppression is in terms of energy loss of the parent (fragmenting) parton in a dense color-charge medium. We have performed a quantitative comparison between various parton energy-loss models and our experimental data. The statistical point-to-point uncorrelated as well as correlated systematic uncertainties are taken into account in the comparison. We detail this methodology and the resulting constraint on the model parameters, such as the initial color-charge density dNg/dy, the medium transport coefficient q, or the …

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