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2001

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The Impact Of Software Evolution On Code Coverage Information, Sebastian Elbaum, David Gable, Gregg Rothermel Jan 2001

The Impact Of Software Evolution On Code Coverage Information, Sebastian Elbaum, David Gable, Gregg Rothermel

School of Computing: Conference and Workshop Papers

Many tools and techniques for addressing software maintenance problems rely on code coverage information. Often, this coverage information is gathered for a specific version of a software system, and then used to perform analyses on subsequent versions of that system without being recalculated. As a software system evolves, however, modifications to the software alter the software’s behavior on particular inputs, and code coverage information gathered on earlier versions of a program may not accurately reflect the coverage that would be obtained on later versions. This discrepancy may affect the success of analyses dependent on code coverage information. Despite the importance …

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Population Characteristics And Food Habitats Of White Perch (Morone Americana) In Branched Oak, Nebraska, Cara Hodking Jan 2001

Population Characteristics And Food Habitats Of White Perch (Morone Americana) In Branched Oak, Nebraska, Cara Hodking

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Field Trip Guide (For The Nebraska Well Drillers Association) Western Nebraska Geology, J. Cannia, D. Weinert, D. Brost, C. Miller, D. Carlson Jan 2001

Field Trip Guide (For The Nebraska Well Drillers Association) Western Nebraska Geology, J. Cannia, D. Weinert, D. Brost, C. Miller, D. Carlson

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Finding The Meanings Of College Drinking: An Analysis Of Fraternity Drinking Stories, Thomas Workman Jan 2001

Finding The Meanings Of College Drinking: An Analysis Of Fraternity Drinking Stories, Thomas Workman

Department of Communication Studies: Faculty Publications

College drinking has traditionally been studied from a public health perspective that attempts to quantify behavior as a means toward description, explanation, and intervention. This article offers a critical and cultural approach to understanding the meanings and functions of high-risk drinking and the ways in which those meanings are reproduced within the culture. Data were collected via an ethnographic study of fraternity members at a large midwestern university to explore the communication of excessive drinking norms. Viewed from various narrative and structural theories, the study examines collected drinking stories as a source for analyzing the construction of meanings surrounding drunkenness …

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Technology As The Representative Anecdote In Popular Discourses Of Health And Medicine, Lynn M. Harter, Phyllis Japp Jan 2001

Technology As The Representative Anecdote In Popular Discourses Of Health And Medicine, Lynn M. Harter, Phyllis Japp

Department of Communication Studies: Faculty Publications

Using a Burkean framework (1969), this article approaches medical dramas as cultural texts to be read for dominant meanings of health and health care. Burke’s representative anecdote illuminates the melding of science, technology, and healing in popular discourses of health, establishing technological intervention as the norm and marginalizing nontechnological (i.e., alternative) forms of health care. Popular entertainment reinforces this anecdote in narratives of healing as technological competence triumphing over nature.

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Adaptive Segmentation Of Document Images, Don Sylwester, Sharad C. Seth Jan 2001

Adaptive Segmentation Of Document Images, Don Sylwester, Sharad C. Seth

School of Computing: Conference and Workshop Papers

A single-parameter text-line extraction algorithm is described along with an efficient technique for estimating the optimal value for the parameter for individual images without need for ground truth. The algorithm is based on three simple tree operations, cut, glue and flip. An XY-tree representing the segmentation is incrementally transformed to reflect a change in the parameter while intrinsic measures of the cost of the transformation are used to detect when specific tree operations would cause an error if they were performed, allowing these errors to be avoided. The algorithm correctly identified 98.8% of the area of the ground truth bounding …

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A Generator Of Random Instances Of Binary Finite Constraint Satisfaction Problems With Controllable Levels Of Interchangeability, Hui Zou, Amy Beckwith, Berthe Y. Choueiry Jan 2001

A Generator Of Random Instances Of Binary Finite Constraint Satisfaction Problems With Controllable Levels Of Interchangeability, Hui Zou, Amy Beckwith, Berthe Y. Choueiry

School of Computing: Technical Reports

In order to test the performance of algorithms for solving Constraint Satisfaction Problems (CSPs), we must establish a large collection of CSP instances that meet a given set of specifications, such as the number of variables, domain size, constraint density, tightness, etc. The goal of this report is to describe a generator of instances that have a specified degree of interchangeability. An example of such a generator is described in (Freuder and Sabin 1997), which generates non-reflexive constraints and does not allow us to control concurrently the degree of interchangeability and tightness. We have developed a technique and written a …

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Infrastructure Support For Controlled Experimentation With Software Testing And Regression Testing Techniques, Hyunsook Do, Sebastian Elbaum, Gregg Rothermel Jan 2001

Infrastructure Support For Controlled Experimentation With Software Testing And Regression Testing Techniques, Hyunsook Do, Sebastian Elbaum, Gregg Rothermel

School of Computing: Technical Reports

Where the creation, understanding, and assessment of software testing and regression testing techniques are concerned, controlled experimentation is an indispensable research methodology. Obtaining the infrastructure necessary to support such experimentation, however, is difficult and expensive. As a result, progress in experimentation with testing techniques has been slow, and empirical data on the costs and effectiveness of techniques remains relatively scarce. To help address this problem, we have been designing and constructing infrastructure to support controlled experimentation with testing and regression testing techniques. This paper reports on the challenges faced by researchers experimenting with testing techniques, including those that inform the …

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Hierarchical Ring Network Configuration And Performance Modeling, V. Carl Hamacher, Hong Jiang Jan 2001

Hierarchical Ring Network Configuration And Performance Modeling, V. Carl Hamacher, Hong Jiang

School of Computing: Faculty Publications

Approximate analytical queuing network models for expected message packet delay in 2-level and 3-level hierarchical ring interconnection networks (INs) are developed. A major class of traffic carried by these INs consists of cache line transfers between processor caches and remote memory modules in shared-memory multiprocessors. Such traffic consists of short, fixed-length messages; they can be conveniently transported by the slotted-ring transmission technique which is studied here. The packet delay results derived from the models are shown to be quite accurate when checked against a simulation study. As well as facilitating analysis, the analytical models can be used to determine optimal …

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Hierarchy-Based Access Control In Distributed Environments, Jean-Camille Birget, Xukai Zou, Guevara Noubir, Byrav Ramamurthy Jan 2001

Hierarchy-Based Access Control In Distributed Environments, Jean-Camille Birget, Xukai Zou, Guevara Noubir, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

Access control is a fundamental concern in any system that manages resources, e.g., operating systems, file systems, databases and communications systems. The problem we address is how to specify, enforce, and implement access control in distributed environments. This problem occurs in many applications such as management of distributed project resources, e-newspaper and payTV subscription services.

Starting from an access relation between users and resources, we derive a user hierarchy, a resource hierarchy, and a unified hierarchy. The unified hierarchy is then used to specify the access relation in a way that is compact and that allows efficient queries. It is …

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Resource Notes-Academic Year 2000-01 Jan 2001

Resource Notes-Academic Year 2000-01

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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The Great Plains Natural Resources And Environmental Change Survey Report, D. C. Gosselin, R. Levy, D. Geise Jan 2001

The Great Plains Natural Resources And Environmental Change Survey Report, D. C. Gosselin, R. Levy, D. Geise

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Logan County Test Hole Logs, Perry B. Wigley Jan 2001

Logan County Test Hole Logs, Perry B. Wigley

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Results Of Whole-Rock Organic Geochemical Analyses Of The Crp-3 Drillcore, Victoria Land Basin, Antarctica, Richard M. Kettler Jan 2001

Results Of Whole-Rock Organic Geochemical Analyses Of The Crp-3 Drillcore, Victoria Land Basin, Antarctica, Richard M. Kettler

Department of Earth and Atmospheric Sciences: Faculty Publications

Sediments and rocks recovered in CRP-3 coring operations contain minute amounts of organic matter (average 0.3% TOC). TOC contents and C:N ratios are zoned systematically: those rocks encountered at depths greater than 330 meters below sea floor (mbsf) contain less organic matter and have higher TOC:N ratios (after correcting for inorganic N) than do shallower rocks. The only two samples that have TOC values greater than 1% also contain abundant granule to silt-sized particles of coal. The total sulphur contents of these rocks is very low and indicates either that only small amounts of deposited organic matter were labile, or …

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Facies Architecture Of The Crp-3 Drillhole, Victoria Land Basin, Antarctica, Christopher R. Fielding, T. R. Naish, K. J. Woolfe Jan 2001

Facies Architecture Of The Crp-3 Drillhole, Victoria Land Basin, Antarctica, Christopher R. Fielding, T. R. Naish, K. J. Woolfe

Department of Earth and Atmospheric Sciences: Faculty Publications

The Cenozoic Victoria Land Basin (VLB) stratigraphic section penetrated by CRP-3 is mostly of Early Oligocene age. It contains an array of lithofacies comprising fine-grained mudrocks, interlaminated and interbedded mudrocks/sandstones, mud-rich and mud-poor sandstones, conglomerates and diamctites that are together interpreted as the products of shallow marine to possibly non-marine environments of deposition, affected by the periodic advance and retreat of tidewater glaciers. This lithofacies assemblage can be readily rationalised using the facies scheme designed originally for CRP-2/2A, and published previously. The uppermost 330 metres below sea floor (mbsf) shows a cyclical arrangement of lithofacies also similar to that recognised …

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Depositional Environments For Strata Cored In Crp-3 (Cape Roberts Project), Victoria Land Basin, Antarctica: Palaeoglaciological And Palaeoclimatological Inferences, R. D. Powell, M. G. Laird, T. R. Naish, Christopher R. Fielding, L. A. Krissek, J.J. M. Van Der Meer Jan 2001

Depositional Environments For Strata Cored In Crp-3 (Cape Roberts Project), Victoria Land Basin, Antarctica: Palaeoglaciological And Palaeoclimatological Inferences, R. D. Powell, M. G. Laird, T. R. Naish, Christopher R. Fielding, L. A. Krissek, J.J. M. Van Der Meer

Department of Earth and Atmospheric Sciences: Faculty Publications

Cape Roberts Project drill core 3 (CRP-3) was obtained from Roberts ridge, a sea-floor high located at 77oS, 12 km offshore from Cape Roberts in western McMurdo Sound, Antarctica. The recovered core is about 939 m long and comprises strata dated as being early Oligocene (possibly latest Eocene) in age, resting unconformably on ~116 m of basement rocks consisting of Palaeozoic Beacon Supergroup sediments. The core includes ten facies commonly occurring in five major associations that are repeated in particular sequences throughout the core and which are interpreted as representing different depositional environments through time. Depositional systems inferred …

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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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