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2001

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Comparison Of Interannual Snowmelt-Onset Dates With Atmospheric Conditions, Sheldon D. Drobot, Mark R. Anderson Jan 2001

Comparison Of Interannual Snowmelt-Onset Dates With Atmospheric Conditions, Sheldon D. Drobot, Mark R. Anderson

Department of Earth and Atmospheric Sciences: Faculty Publications

The snowmelt-onset date represents an important transitional point in the Arctic surface energy balance, when albedo decreases and energy absorption increases rapidly in response to the appearance of liquid water. Interannual variations in snowmelt onset are likely related to large-scale variations in atmospheric circulation, such as described by the Arctic Oscillation (AO). This research therefore examines the relationship between monthly-averaged AO values and mean annual snowmelt-onset dates over Arctic sea ice in 13 regions, from 1979 to 1998. The objective is to statistically relate variations in mean annual regional snowmelt-onset dates to variations in the AO. Additionally, monthly-averaged 500 hPa …

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The Onset Of Arctic Sea-Ice Snowmelt As Detected With Passive- And Active-Microwave Remote Sensing, Richard R. Forster, David G. Long, Kenneth C. Jezek, Sheldon D. Drobot, Mark R. Anderson Jan 2001

The Onset Of Arctic Sea-Ice Snowmelt As Detected With Passive- And Active-Microwave Remote Sensing, Richard R. Forster, David G. Long, Kenneth C. Jezek, Sheldon D. Drobot, Mark R. Anderson

Department of Earth and Atmospheric Sciences: Faculty Publications

Daily acquisitions from satellite microwave sensors can be used to observe the spatial and temporal characteristics of the Arctic sea-ice snowmelt onset because the initial presence of liquid water in a dry snowpack causes a dramatic change in the active and passive-microwave response. A daily sequence of backscatter coefficient images from the NASA scatterometer (NSCAT) clearly shows the spatially continuous progression of decreasing backscatter associated with snowmelt onset across the Arctic Ocean during spring 1997. A time series of the active NSCAT backscatter and a scattering index from the passive Special Sensor Microwave/Imager (SSM/I) show similar trends during the time …

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Spatial And Temporal Variability In Snowmelt Onset Over Arctic Sea Ice, Mark R. Anderson, Sheldon D. Drobot Jan 2001

Spatial And Temporal Variability In Snowmelt Onset Over Arctic Sea Ice, Mark R. Anderson, Sheldon D. Drobot

Department of Earth and Atmospheric Sciences: Faculty Publications

Climate models suggest surface warming in the Arctic will be rapid and pronounced, implying substantial changes in snowmelt onset are likely. This research therefore examines spatial and temporal variability in passive-microwave derived snowmelt-onset dates over Arctic sea ice. The objectives are to understand better the regional characteristics of snowmelt and to document whether the snowmelt-onset record shows signs of climate change. Snowmelt-onset dates are derived with Scanning Multichannel Microwave Radiometer and Special Sensor Microwave/Imager brightness-temperature data, and they are subsequently stratified into 13 regions to analyze spatial and temporal variability. Results illustrate significant spatial variability in snowmelt onset, with the …

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Drawdown And Stream Depletion Produced By Pumping In The Vicinity Of A Partially Penetrating Stream, James J. Butler Jr., Vitaly A. Zlotnik, Ming-Shu Tsou Jan 2001

Drawdown And Stream Depletion Produced By Pumping In The Vicinity Of A Partially Penetrating Stream, James J. Butler Jr., Vitaly A. Zlotnik, Ming-Shu Tsou

Department of Earth and Atmospheric Sciences: Faculty Publications

Commonly used analytical approaches for estimation of pumping-induced drawdown and stream depletion are based on a series of idealistic assumptions about the stream-aquifer system. Anew solution has been developed for estimation of drawdown and stream depletion under conditions that are more representative of those in natural systems (finite width stream of shallow penetration adjoining an aquifer of limited lateral extent). This solution shows that the conventional assumption of a fully penetrating stream will lead to a significant overestimation of stream depletion (> 100%) in many practical applications. The degree of overestimation will depend on the value of the stream leakance …

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Ancestral Divergence, Genome Diversification, And Phylogeographic Variation In Subpopulations Of Sorbitol-Negative, Β-Glucuronidase- Negative Enterohemorrhagic Escherichia Coli O157, Jaehyoung Kim, Joseph Nietfeldt, Jingliang Ju, John Wise, Narelle Fegan, Patricia Desmarchelier, Andrew K. Benson Jan 2001

Ancestral Divergence, Genome Diversification, And Phylogeographic Variation In Subpopulations Of Sorbitol-Negative, Β-Glucuronidase- Negative Enterohemorrhagic Escherichia Coli O157, Jaehyoung Kim, Joseph Nietfeldt, Jingliang Ju, John Wise, Narelle Fegan, Patricia Desmarchelier, Andrew K. Benson

Department of Food Science and Technology: Faculty Publications

The O157:H7 lineage of enterohemorrhagic Escherichia coli is a geographically disseminated complex of highly related genotypes that share common ancestry. The common clone that is found worldwide carries several markers of events in its evolution, including markers for acquisition of virulence genes and loss of physiological characteristics, such as sorbitol fermentation ability and β-glucuronidase production. Populations of variants that are distinct with respect to motility and the sorbitol and β-glucuronidase markers appear to have diverged at several points along the inferred evolutionary pathway. In addition to these variants, distinct subpopulations of the contemporary non-sorbitol-fermenting, β-glucuronidase-negative O157:H7 clone were recently detected …

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Tracking Of Moving Objects In Scenery Using Subspace Projection Using Independent Component Analysis, Brian J. Noe, Fredric M. Ham Jan 2001

Tracking Of Moving Objects In Scenery Using Subspace Projection Using Independent Component Analysis, Brian J. Noe, Fredric M. Ham

Aerospace, Physics, and Space Science Faculty Publications

A system is developed for tracking moving objects though natural scenery. A technique is presented for performing change detection on imagery to determine the difference between two images or a sequence of images. Form there an algorithm is presented to detect the presence of a new object and/or the deletion of objects. Then the application of a Variable Structure Interacting Multiple Model tracking filter is presented. The method of performing change detection is based upon the concept of image subspace projection. A set of basis image maps are formed when combined with a mixing matrix can recreate the original image. …

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Multiband Microvariability Observations Of Bl Lacertae During The Outburst Of 1997, Sandra D. Clements, Michael T. Carini Jan 2001

Multiband Microvariability Observations Of Bl Lacertae During The Outburst Of 1997, Sandra D. Clements, Michael T. Carini

Aerospace, Physics, and Space Science Faculty Publications

BL Lac was observed in the V and R bands on 11 nights in 1997 July during a major optical outburst. It varied continuously, exhibiting nightly variations ranging from 0.1 to 0.6 mag. Over the course of the 11 nights, BL Lac was seen to vary by 1.8 R magnitudes. Color variations were also observed, with BL Lac becoming bluer as it brightened. The influence of variable seeing conditions on the observed variations was investigated. No correlation was found between the observed microvariability and the local seeing conditions.

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On The Origin Of Reverse Polarity Tcrs, Mark B. Moldwin, Michael R. Collier, James A. Slavin, Adam Szabo Jan 2001

On The Origin Of Reverse Polarity Tcrs, Mark B. Moldwin, Michael R. Collier, James A. Slavin, Adam Szabo

Aerospace, Physics, and Space Science Faculty Publications

Reverse polarity, or South-then-North (SN) bipolar, traveling compression regions (SN TCRs) are often observed in the Earth's magnetotail lobes. These events have been interpreted as either slowly earthward propagating "proto-plasmoids" during extremely quiet geomagnetic conditions, or due to pressure pulses in the solar wind or magnetosheath compressing the magnetotail. This study presents a survey of 21 IMP 8 observations of SN TCRs and the corresponding solar wind pressure conditions as measured by WIND. We found that solar wind or magnetosheath pressure pulses nicely explain most (17), though not all, of the SN TCR observations. Therefore, it appears that both explanations …

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Non-Technology Issues: The Human-Side Factors In Online Education, Qinghua Yu Jan 2001

Non-Technology Issues: The Human-Side Factors In Online Education, Qinghua Yu

Graduate Research Papers

As much as the explosive growth of electronic communication, things have changed in business, education and our society. Many professionals are thinking about the training and skill base in the area of technologies. How can instructors translate their teaching skills in a successful teaching online (Addesso, 2000). Coldeway (1988) acknowledges that the focus of most distance education institutions is on the technology but suggests that the research is shifting to the more human side of distance learning as the programs age. Using the current research on the problems addressed, as well as philosophies and theories implemented in online environments, this …

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Fundamental Design Considerations For Creating Web Pages, Damon Staker Jan 2001

Fundamental Design Considerations For Creating Web Pages, Damon Staker

Graduate Research Papers

Fundamental Design Considerations for Creating Web Pages is a graduate review paper that was written to increase awareness of the proper use of design principles and web page layout in designing school web sites. This was written in response to the increase of poorly designed web sites that are difficult to read and understand because of the use of improper text and text size, distracting backgrounds, and color combinations that do not match. Information is given as to what design considerations and background information is needed to create a web site. The use of tables and frames is compared along …

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Minority Dropout And Prevention, Ryan J. Williamson Jan 2001

Minority Dropout And Prevention, Ryan J. Williamson

Graduate Research Papers

Dropping out of high school has long been viewed as a serious educational and social problem, especially for minorities (Jordan, Lara, & McPartland, 1996). By leaving high school prior to completion, most dropouts have serious educational deficiencies that severely limit their economic and social well being throughout their adult lives.

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A Direct Correlation Function For Mesomorphic Polymers And Its Application To The ‘Smectic’ Phase Of Isotactic Polypropylene, Y Cohen, Ravi F. Saraf Jan 2001

A Direct Correlation Function For Mesomorphic Polymers And Its Application To The ‘Smectic’ Phase Of Isotactic Polypropylene, Y Cohen, Ravi F. Saraf

Papers in Materials Science

A general model to calculate the structure of a smectic to nematic-like order in polymer systems is proposed. The model is limited to well-aligned molecules with respect to each other. It is especially suited for systems where the packing between neighboring chains is described by liquid-like disorder with axial registration in the chain-axis direction. In such a case the diffraction pattern from the oriented structure exhibits broad liquid-like reflections on the equatorial but sharper reflections on the layer lines. An Ornstein-Zernike approach is adopted to calculate the inter-chain packing and inter-chain registration, where the direct correlation function of packing and …

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Relationship Between Durophagy And Feeding Biomechanics In Gray Triggerfish, Balistes Capriscus: Intraspecific Variation In Ecological Morphology, Christopher J. Durie, Ralph G. Turingan Jan 2001

Relationship Between Durophagy And Feeding Biomechanics In Gray Triggerfish, Balistes Capriscus: Intraspecific Variation In Ecological Morphology, Christopher J. Durie, Ralph G. Turingan

Ocean Engineering and Marine Sciences Faculty Publications

The relationship between oral jaw biomechanics and consumption of hard prey was compared between Gulf of Mexico (Gulf) and Atlantic Ocean (Atlantic) populations of gray triggerfish (Balistes capriscus) to examine intraspecific ecomorphological variation between these fish. Gut content analysis revealed that Atlantic fish fed more on hard-shelled invertebrates, such as crabs and sea urchins, than Gulf conspecifics. Difference in the relative magnitude of durophagy between Gulf and Atlantic triggerfish was associated with intraspecific differences in key biomechanical properties of the prey-capture and processing mechanism. The more durophagous Atlantic B. capriscus had more massive jaw bones and muscles than Gulf fish. …

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Dino Hayz At The Putnam Museum Of History And Natural Science: Introducing Creative Drama, Theatre For Youth And Participation Theatre As Educational Tools In The Museum Setting, Tess Marlene Lassen Jan 2001

Dino Hayz At The Putnam Museum Of History And Natural Science: Introducing Creative Drama, Theatre For Youth And Participation Theatre As Educational Tools In The Museum Setting, Tess Marlene Lassen

Graduate Research Papers

The intent of this study is to show how the principle of teaching in role through Theatre for Youth, Participation Theatre and Creative Drama were used by Dino Hayz to teach young people about exhibits at the Putnam Museum of History and Natural Science in Davenport, Iowa from 1990 to 2001. When it began, the Heritage Theatre at the Putnum Museum offered short plays or monologues performed in and relating to the museum exhibits. These pieces were performed for the general public, adults and youth. The Theatre Coordinator was Margo Stites. Under the direction of Dino Hayz the role of …

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Making Electronic Resources Available To Patrons, Robert Linz Jan 2001

Making Electronic Resources Available To Patrons, Robert Linz

Faculty Articles

No abstract provided.

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The Application Of Universal Human Rights Law To People With Mental Disabilities, Debra Benko, Brittany Benowitz Jan 2001

The Application Of Universal Human Rights Law To People With Mental Disabilities, Debra Benko, Brittany Benowitz

Human Rights Brief

No abstract provided.

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The Optional Protocols To The Un Convention On The Rights Of The Child On Sex Trafficking And Child Soldiers, Cris R. Revaz Jan 2001

The Optional Protocols To The Un Convention On The Rights Of The Child On Sex Trafficking And Child Soldiers, Cris R. Revaz

Human Rights Brief

No abstract provided.

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Guatemala: Children's Rights Case Wins Judgment At Iachr, Ismene Zarifis Jan 2001

Guatemala: Children's Rights Case Wins Judgment At Iachr, Ismene Zarifis

Human Rights Brief

No abstract provided.

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Legislative Focus: Patriot Act, Mary Ellen Tsekos Jan 2001

Legislative Focus: Patriot Act, Mary Ellen Tsekos

Human Rights Brief

No abstract provided.

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Male Rape In U.S. Prisons: Cruel And Unusual Punishment, Shara Abraham Jan 2001

Male Rape In U.S. Prisons: Cruel And Unusual Punishment, Shara Abraham

Human Rights Brief

No abstract provided.

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China's Crackdown On Falun Gong, Erin Chlopak Jan 2001

China's Crackdown On Falun Gong, Erin Chlopak

Human Rights Brief

No abstract provided.

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Harvest Of Danger: The Child Farmworker In The United States , Teresa Young Reeves Jan 2001

Harvest Of Danger: The Child Farmworker In The United States , Teresa Young Reeves

Human Rights Brief

No abstract provided.

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News From The Inter-American System , Terri J. Harris Jan 2001

News From The Inter-American System , Terri J. Harris

Human Rights Brief

No abstract provided.

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The Impact Of The Protocol To Prevent, Suppress And Punish Trafficking In Persons, Especially Women And Children, Kelly E. Hyland Jan 2001

The Impact Of The Protocol To Prevent, Suppress And Punish Trafficking In Persons, Especially Women And Children, Kelly E. Hyland

Human Rights Brief

No abstract provided.

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Awas Tingni V. Nicaragua: A Landmark Case For The Inter-American System , Claudio Grossman Jan 2001

Awas Tingni V. Nicaragua: A Landmark Case For The Inter-American System , Claudio Grossman

Human Rights Brief

No abstract provided.

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The Right Of Self-Determination: Is East Timor A Viable Model For Kashmir?, Amardeep Singh Jan 2001

The Right Of Self-Determination: Is East Timor A Viable Model For Kashmir?, Amardeep Singh

Human Rights Brief

No abstract provided.

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News From The International Criminal Tribunals , Alexandra L. Wisotsky, Kelly D. Askin Jan 2001

News From The International Criminal Tribunals , Alexandra L. Wisotsky, Kelly D. Askin

Human Rights Brief

No abstract provided.

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Minors In Haiti's Prisons , Ismene Zarifis Jan 2001

Minors In Haiti's Prisons , Ismene Zarifis

Human Rights Brief

No abstract provided.

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The World Commission On Dams' Contribution To The Broader Debate On Development Decision-Making, Daniel D. Bradlow Jan 2001

The World Commission On Dams' Contribution To The Broader Debate On Development Decision-Making, Daniel D. Bradlow

American University International Law Review

No abstract provided.

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Volume Management In San Environment, Chang-Soo Kim, Gyoung-Bae Kim, Bum-Joo Shin Jan 2001

Volume Management In San Environment, Chang-Soo Kim, Gyoung-Bae Kim, Bum-Joo Shin

Electrical and Computer Engineering Faculty Research & Creative Works

Logical volume managers have long been key components of a storage system. Their key features are creation of logical or virtual views of physical storage devices and support for various software RAID levels. These make it possible to overcome the limits to capacity, availability and performance of a physical storage device. Most logical volume managers are operated in a single system environment. They are not adequate for SAN (storage area network) environments where several hosts share and access a logical volume at the same time. Some recent logical volume managers are run in a multi-host environment. However, they cannot support …

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