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2010

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Diagonal Forms And The Rationality Of The Poincaré Series, Dibyajyoti Deb Jan 2010

Diagonal Forms And The Rationality Of The Poincaré Series, Dibyajyoti Deb

University of Kentucky Doctoral Dissertations

The Poincaré series, Py(f) of a polynomial f was first introduced by Borevich and Shafarevich in [BS66], where they conjectured, that the series is always rational. Denef and Igusa independently proved this conjecture. However it is still of interest to explicitly compute the Poincaré series in special cases. In this direction several people looked at diagonal polynomials with restrictions on the coefficients or the exponents and computed its Poincaré series. However in this dissertation we consider a general diagonal polynomial without any restrictions and explicitly compute its Poincaré series, thus extending results of Goldman, Wang and Han. In a separate …

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Just How Right Are The Customers? An Analysis Of The Relative Performance Of Patron-Initiated Interlibrary Loan Monograph Purchases, David C. Tyler, Yang Xu, Joyce C. Melvin, Marylou Epp, Anita M. Kreps Jan 2010

Just How Right Are The Customers? An Analysis Of The Relative Performance Of Patron-Initiated Interlibrary Loan Monograph Purchases, David C. Tyler, Yang Xu, Joyce C. Melvin, Marylou Epp, Anita M. Kreps

University of Nebraska-Lincoln Libraries: Faculty Publications

There has been a flurry of interest in programs for collection development through patron-initiated requests. However, some librarians have been concerned that such methods run the risk of producing idiosyncratic collections with poor usage and poor use value. The University of Nebraska-Lincoln Libraries have operated such a program through the Interlibrary Loan Department over a fiveyear period. The following study assesses the relative performance of the program’s interlibrary loan–acquired monographs in terms of prices paid per rates of annual circulation, relative use at the topical level, and annual rates of circulation.

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Genbank, Dennis A. Benson, Ilene Karasch-Mizrachi, David J. Lipman, James Ostell, Eric W. Sayers Jan 2010

Genbank, Dennis A. Benson, Ilene Karasch-Mizrachi, David J. Lipman, James Ostell, Eric W. Sayers

Harold W. Manter Laboratory of Parasitology: Library Materials

GenBank(R) is a comprehensive database that contains publicly available nucleotide sequences for more than 380,000 organisms named at the genus level or lower, obtained primarily through submissions from individual laboratories and batch submissions from large-scale sequencing projects, including whole genome shotgun (WGS) and environmental sampling projects. Most submissions are made using the web-based BankIt or standalone Sequin programs, and accession numbers are assigned by GenBank staff upon receipt. Daily data exchange with the European Nucleotide Archive (ENA) and the DNA Data Bank of Japan (DDBJ) ensures worldwide coverage. GenBank is accessible through the NCBI Entrez retrieval system that integrates data …

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A Novel Weighted-Graph-Based Grouping Algorithm For Metadata Prefetching, Peng Gu, Jun Wang, Yifeng Zhu, Hong Jiang, Pengju Shang Jan 2010

A Novel Weighted-Graph-Based Grouping Algorithm For Metadata Prefetching, Peng Gu, Jun Wang, Yifeng Zhu, Hong Jiang, Pengju Shang

School of Computing: Faculty Publications

Although data prefetching algorithms have been extensively studied for years, there is no counterpart research done for metadata access performance. Existing data prefetching algorithms, either lack of emphasis on group prefetching, or bearing a high level of computational complexity, do not work well with metadata prefetching cases. Therefore, an efficient, accurate, and distributed metadata-oriented prefetching scheme is critical to leverage the overall performance in large distributed storage systems. In this paper, we present a novel weighted-graph-based prefetching technique, built on both direct and indirect successor relationship, to reap performance benefit from prefetching specifically for clustered metadata servers, an arrangement envisioned …

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Xlp: A Cross-Layer Protocol For Efficient Communication In Wireless Sensor Networks, Mehmet C. Vuran, Ian F. Akyildiz Jan 2010

Xlp: A Cross-Layer Protocol For Efficient Communication In Wireless Sensor Networks, Mehmet C. Vuran, Ian F. Akyildiz

School of Computing: Faculty Publications

Severe energy constraints of battery-powered sensor nodes necessitate energy-efficient communication in Wireless Sensor Networks (WSNs). However, the vast majority of the existing solutions is based on classical layered protocols approach, which leads to significant overhead. It is much more efficient to have a unified scheme which blends common protocol layer functionalities into a cross-layer module. In this paper, a cross layer protocol (XLP) is introduced, which achieves congestion control, routing, and medium access control in a cross-layer fashion. The design principle of XLP is based on the cross-layer concept of initiative determination, which enables receiver-based contention, initiative-based forwarding, local …

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Linear Programming Models For Multi-Channel P2p Streaming Systems, Miao Wang, Lisong Xu, Byrav Ramamurthy Jan 2010

Linear Programming Models For Multi-Channel P2p Streaming Systems, Miao Wang, Lisong Xu, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

Most of the commercial P2P video streaming deployments support hundreds of channels and are referred to as multichannel systems. Measurement studies show that bandwidth resources of different channels are highly unbalanced and thus recent research studies have proposed various protocols to improve the streaming qualities for all channels by enabling cross-channel cooperation among multiple channels. However, there is no general framework for comparing existing and potential designs for multi-channel P2P systems. The goal of this paper is to establish tractable models for answering the fundamental question in multi-channel system designs: Under what circumstances, should a particular design be used to …

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Spatio-Temporal Soil Moisture Measurement With Wireless Underground Sensor Networks, Xin Dong, Mehmet C. Vuran Jan 2010

Spatio-Temporal Soil Moisture Measurement With Wireless Underground Sensor Networks, Xin Dong, Mehmet C. Vuran

School of Computing: Conference and Workshop Papers

In this paper, the estimation distortion of distributed soil moisture measurement using Wireless Underground Sensor Networks (WUSNs) is investigated. The main focus of this paper is to analyze the impact of the environment and network parameters on the estimation distortion of the soil moisture.More specifically, the effects of rainfall, soil porosity, and vegetation root zone are investigated by exploiting a rainfall model, in addition to the effects of sampling rate, network topology, and measurement signal noise ratio. Spatio-temporal correlation is characterized to develop a measurement distortion model with respect to these factors. The evaluations reveal that with porous soil and …

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A First Practical Algorithm For High Levels Of Relational Consistency, Shant Karakashian, Robert J. Woodward, Christopher Reeson, Berthe Y. Choueiry, Christian Bessiere Jan 2010

A First Practical Algorithm For High Levels Of Relational Consistency, Shant Karakashian, Robert J. Woodward, Christopher Reeson, Berthe Y. Choueiry, Christian Bessiere

School of Computing: Conference and Workshop Papers

Consistency properties and algorithms for achieving them are at the heart of the success of Constraint Programming. In this paper, we study the relational consistency property R(*,m)C, which is equivalent to m-wise consistency proposed in relational databases. We also define wR(*,m)C, a weaker variant of this property. We propose an algorithm for enforcing these properties on a Constraint Satisfaction Problem by tightening the existing relations and without introducing new ones. We empirically show that wR(*,m)C solves in a backtrackfree manner all the instances of some CSP benchmark classes, thus hinting at the tractability …

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A Partial Taxonomy Of Substitutability And Interchangeability, Shant Karakashian, Robert J. Woodward, Berthe Y. Choueiry, Steven D. Prestwich, Eugene C. Freuder Jan 2010

A Partial Taxonomy Of Substitutability And Interchangeability, Shant Karakashian, Robert J. Woodward, Berthe Y. Choueiry, Steven D. Prestwich, Eugene C. Freuder

School of Computing: Conference and Workshop Papers

Substitutability, interchangeability and related concepts in Constraint Programming were introduced approximately twenty years ago and have given rise to considerable subsequent research. We survey this work, classify, and relate the different concepts, and indicate directions for future work, in particular with respect to making connections with research into symmetry breaking. This paper is a condensed version of a larger work in progress.

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Vision Graph Construction In Wireless Multimedia Sensor Networks, Xin Dong, Mehmet C. Vuran Jan 2010

Vision Graph Construction In Wireless Multimedia Sensor Networks, Xin Dong, Mehmet C. Vuran

School of Computing: Conference and Workshop Papers

In Wireless multimedia sensor networks (WMSNs), the camera nodes connected in the vision graph share overlapped field of views (FOVs) and they depend on the densely deployed relay nodes in the communication network graph to communicate with each other. Given a uniformly deployed camera sensor network with relay nodes, the problem is to find the number of hops for the vision-graph-neighbor-searching messages to construct the vision graph in an energy efficient way. In this paper, mathematical models are developed to analyze the FOV overlap of the camera nodes and the multi-hop communications in two dimensional topologies, which are utilized to …

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Implementation Of A Relationship-Based School Readiness Intervention: A Multidimensional Approach To Fidelity Measurement For Early Childhood, Lisa L. Knoche, Susan M. Sheridan, Carolyn P. Edwards, Allison Q. Osborn Jan 2010

Implementation Of A Relationship-Based School Readiness Intervention: A Multidimensional Approach To Fidelity Measurement For Early Childhood, Lisa L. Knoche, Susan M. Sheridan, Carolyn P. Edwards, Allison Q. Osborn

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

The implementation efforts of 65 early childhood professionals involved in the Getting Ready project, an integrated, multi-systemic intervention that promotes school readiness through parent engagement for children from birth to age five, were investigated. Digital videotaped records of professionals engaged in home visits with families across both treatment and comparison conditions were coded objectively using a partial–interval recording system to identify and record early childhood professionals’ implementation of intervention strategies and their effectiveness in promoting parent engagement and interest in their child. Adherence, quality of intervention delivery, differentiation between groups, and participant responsiveness were assessed as multiple dimensions of fidelity. …

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Parent Engagement And School Readiness: Effects Of The Getting Ready Intervention On Preschool Children’S Social-Emotional Competencies, Susan M. Sheridan Dr., Lisa Knoche, Carolyn P. Edwards, James A. Bovaird, Kevin A. Kupzyk Jan 2010

Parent Engagement And School Readiness: Effects Of The Getting Ready Intervention On Preschool Children’S Social-Emotional Competencies, Susan M. Sheridan Dr., Lisa Knoche, Carolyn P. Edwards, James A. Bovaird, Kevin A. Kupzyk

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

Research Findings: Parental engagement with children has been linked to a number of adaptive characteristics in preschool children, and relationships between families and professionals are an important contributor to school readiness. Furthermore, social-emotional competence is a key component of young children’s school readiness. This study reports the results of a randomized trial of a parent engagement intervention (Getting Ready) designed to facilitate school readiness among disadvantaged preschool children, with a particular focus on social-emotional outcomes. Two hundred and twenty children were involved over the 4-year study period. Statistically significant differences were observed between treatment and control participants in the rate …

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Centennial Eolian Cyclicity In The Great Plains, Usa: A Dominant Climate Pattern Of Wind Transport Over The Past 4000 Years?, Antje Schwalb, Walter E. Dean, Sherilyn C. Fritz, Christoph E. Geiss, Bernd Kromer Jan 2010

Centennial Eolian Cyclicity In The Great Plains, Usa: A Dominant Climate Pattern Of Wind Transport Over The Past 4000 Years?, Antje Schwalb, Walter E. Dean, Sherilyn C. Fritz, Christoph E. Geiss, Bernd Kromer

Department of Earth and Atmospheric Sciences: Faculty Publications

Proxy evidence at decadal resolution from Late Holocene sediments from Pickerel Lake, northeastern South Dakota, shows distinct centennial cycles (400-700 years) in magnetic susceptibility; contents of carbonate, organic carbon, and major elements; abundance in ostracodes; and δ18O and δ13C values in calcite. Proxies indicate cyclic changes in eolian input, productivity, and temperature. Maxima in magnetic susceptibility are accompanied by maxima in aluminum and iron mass accumulation rates (MARs), and in abundances of the ostracode Fabaeformiscandona rawsoni. This indicates variable windy, and dry conditions with westerly wind dominance, including during the Medieval Climate Anomaly. Maxima in …

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Groundwater Recharge In Natural Dune Systems And Agricultural Ecosystems In The Thar Desert Region, Rajasthan, India, Bridget Scanlon, Abhijit Mukherjee, John B. Gates, Robert C. Reedy, Amarendra K. Sinha Jan 2010

Groundwater Recharge In Natural Dune Systems And Agricultural Ecosystems In The Thar Desert Region, Rajasthan, India, Bridget Scanlon, Abhijit Mukherjee, John B. Gates, Robert C. Reedy, Amarendra K. Sinha

Department of Earth and Atmospheric Sciences: Faculty Publications

Water and nutrient availability for crop production are critical issues in (semi)arid regions. Unsaturated-zone Cl tracer data and nutrient (NO3 and PO4) concentrations were used to quantify recharge rates using the Cl mass balance approach and nutrient availability in the Thar Desert, Rajasthan, India. Soil cores were collected in dune/interdune settings in the arid Thar Desert (near Jaisalmer) and in rain-fed (nonirrigated) and irrigated cropland in the semiarid desert margin (near Jaipur). Recharge rates were also simulated using unsaturated zone modeling. Recharge rates in sparsely vegetated dune/interdune settings in the Jaisalmer study area are 2.7-5.6 mm/year (2-3% …

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Stratigraphic Signature Of The Late Palaeozoic Ice Age In The Parmeener Supergroup Of Tasmania, Se Australia, And Inter-Regional Comparisons, Christopher R. Fielding, Tracy D. Frank, John L. Isbell, Lindsey C. Henry, Eugene W. Domack Jan 2010

Stratigraphic Signature Of The Late Palaeozoic Ice Age In The Parmeener Supergroup Of Tasmania, Se Australia, And Inter-Regional Comparisons, Christopher R. Fielding, Tracy D. Frank, John L. Isbell, Lindsey C. Henry, Eugene W. Domack

Department of Earth and Atmospheric Sciences: Faculty Publications

Recent research in eastern Australia has established that rather than being a single, long-lived epoch, the late Palaeozoic Ice Age comprised a series of glacial intervals each 1–8 million years in duration, separated by non-glacial intervals of comparable duration. In order to test whether the glacial events recognized in New South Wales and Queensland have broader extent, we conducted a reappraisal of the Parmeener Supergroup of Tasmania, southeast Australia. A facies analysis of the Pennsylvanian to Permian section was carried out, allowing rationalization of the succession into four recurrent facies associations: a) glacigenic facies association, restricted to the basal Pennsylvanian/earliest …

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Tetrapod Fauna Of The Lowermost Usili Formation (Songea Group, Ruhuhu Basin) Of Southern Tanzania, With A New Burnetiid Record, Christian A. Sidor, Kenneth D. Angielczyk, D. Marie Weide, Roger M. H. Smith, Sterling J. Nesbitt, Linda A. Tsuji Jan 2010

Tetrapod Fauna Of The Lowermost Usili Formation (Songea Group, Ruhuhu Basin) Of Southern Tanzania, With A New Burnetiid Record, Christian A. Sidor, Kenneth D. Angielczyk, D. Marie Weide, Roger M. H. Smith, Sterling J. Nesbitt, Linda A. Tsuji

Department of Earth and Atmospheric Sciences: Faculty Publications

Vertebrate fossils from the Ruhuhu Basin of southern Tanzania have been known for over 75 years, but the details of their stratigraphic distribution remain imperfectly understood. Recent fieldwork in the Upper Permian Usili Formation (Songea Group) has led to the discovery of a tetrapod assemblage in a conglomeratic unit at its base. The fossils are concentrated in matrix-supported intraformational clay pebble conglomerates interpreted as mass flow deposits in wide, shallow channels in the distal reaches of an alluvial fan. Included in this new collection are fossils representing the first record of a burnetiid therapsid from Tanzania. The anatomy of the …

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Improved Algorithm For Modis Satellite Retrievals Of Aerosol Optical Thickness Over Land In Dusty Atmosphere: Implications For Air Quality Monitoring In China, Jun Wang, Xiaoguang Xu, R. Spurr, Yuxuang Wang, Easan Drury Jan 2010

Improved Algorithm For Modis Satellite Retrievals Of Aerosol Optical Thickness Over Land In Dusty Atmosphere: Implications For Air Quality Monitoring In China, Jun Wang, Xiaoguang Xu, R. Spurr, Yuxuang Wang, Easan Drury

Department of Earth and Atmospheric Sciences: Faculty Publications

A new algorithm, using the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite reflectance and aerosol single scattering properties simulated from a chemistry transport model (GEOS-Chem), is developed to retrieve aerosol optical thickness (AOT) over land in China during the spring dust season. The algorithmfirst uses a “dynamic lower envelope” approach to sample theMODIS dark-pixel reflectance data in lowAOT conditions, to derive the local surface visible (0.65 μm)/near infrared (NIR, 2.1 μm) reflectance ratio. Joint retrievals of AOT at 0.65 μm and surface reflectance at 2.1 μm are then performed, based on the time, location, and spectraldependent single scattering properties of the …

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Zebulon Pike: Great American Explorer Or Climate Spy?, Merlin P. Lawson, Randall Cerveny, Cary Mock Jan 2010

Zebulon Pike: Great American Explorer Or Climate Spy?, Merlin P. Lawson, Randall Cerveny, Cary Mock

Department of Earth and Atmospheric Sciences: Faculty Publications

Zebulon Pike is known in history books as one of America’s heroes—a great explorer whose adventures in the American West rivaled the Lewis and Clark Expedition and who became the namesake for Colorado’s Pike’s Peak. But what if the history books got it wrong, and Pike was actually not the hero everyone thinks he is? What if he was actually a spy carrying out a secret mission, or a scoundrel interested in overthrowing the American government and helping to carve a new empire out of the North American Southwest? Evidence from Pike’s famed expedition in 1806-1807 points to the possibility …

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Collapse Of The Maya: Could Deforestation Have Contributed?, Robert Oglesby, Thomas L. Sever, William Saturno, David J. Erickson Iii, Jayanthi Srikishen Jan 2010

Collapse Of The Maya: Could Deforestation Have Contributed?, Robert Oglesby, Thomas L. Sever, William Saturno, David J. Erickson Iii, Jayanthi Srikishen

Department of Earth and Atmospheric Sciences: Faculty Publications

The collapse of the Maya civilization during the ninth century A.D. is a major conundrum in the history of mankind. This civilization reached a spectacular peak but then almost completely collapsed in the space of a few decades. While numerous explanations have been put forth to explain this collapse, in recent years, drought has gained favor. This is because water resources were a key for the Maya, especially to ensure their survival during the lengthy dry season that occurs where they lived. Natural drought is a known, recurring feature of this region, as evidenced by observational data, reconstructions of past …

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Effects Of Irrigated Agroecosystems: 2. Quality Of Soil Water And Groundwater In The Southern High Plains, Texas, B. R. Scanlon, J. B. Gates, R. C. Reedy, W. A. Jackson, J. P. Bordovsky Jan 2010

Effects Of Irrigated Agroecosystems: 2. Quality Of Soil Water And Groundwater In The Southern High Plains, Texas, B. R. Scanlon, J. B. Gates, R. C. Reedy, W. A. Jackson, J. P. Bordovsky

Department of Earth and Atmospheric Sciences: Faculty Publications

Trade‐offs between water‐resource depletion and salinization need to be understood when promoting water‐conservative irrigation practices. This companion paper assesses impacts of groundwater‐fed irrigation on soil water and groundwater quality using data from the southern High Plains (SHP). Unsaturated zone soil samples from 13 boreholes beneath irrigated agroecosystems were analyzed for water‐extractable anions. Salt accumulation in soils varies with irrigation water quality, which ranges from low salinity in the north (median Cl: 21 mg/L) to higher salinity in the south (median Cl: 180 mg/L). Large Cl bulges under irrigated agroecosystems in the south are similar to those under natural ecosystems, but …

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Influence Of The Arctic Oscillation On Central United States Summer Rainfall, Qi Hu, Song Feng Jan 2010

Influence Of The Arctic Oscillation On Central United States Summer Rainfall, Qi Hu, Song Feng

Department of Earth and Atmospheric Sciences: Faculty Publications

Effects of the Arctic oscillation (AO) on summer rainfall variability in the central United States are examined in order to improve understanding and prediction of the interannual variation in the summer rainfall. Major results show persistent AO effects that resulted in less summer rainfall in the central United States during the positive phase of the AO and more rainfall during the negative AO phase. These effects are most prominent at the interannual time scale. The key physical processes connecting the AO with the rainfall variations are shown in changes in latitudinal location of the midlatitude upper tropospheric westerly jet over …

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Synthesis Of Satellite (Modis), Aircraft (Icartt), And Surface (Improve, Epa‐Aqs, Aeronet) Aerosol Observations Over Eastern North America To Improve Modis Aerosol Retrievals And Constrain Surface Aerosol Concentrations And Sources, Easan Drury, Daniel J. Jacob, Robert J. D. Spurr, Jun Wang, Yohei Shinozuka, Bruce E. Anderson, Antony D. Clarke, Jack Dibb, Cameron Mcnaughton, Rodney Weber Jan 2010

Synthesis Of Satellite (Modis), Aircraft (Icartt), And Surface (Improve, Epa‐Aqs, Aeronet) Aerosol Observations Over Eastern North America To Improve Modis Aerosol Retrievals And Constrain Surface Aerosol Concentrations And Sources, Easan Drury, Daniel J. Jacob, Robert J. D. Spurr, Jun Wang, Yohei Shinozuka, Bruce E. Anderson, Antony D. Clarke, Jack Dibb, Cameron Mcnaughton, Rodney Weber

Department of Earth and Atmospheric Sciences: Faculty Publications

We use an ensemble of satellite (MODIS), aircraft, and ground‐based aerosol observations during the ICARTT field campaign over eastern North America in summer 2004 to (1) examine the consistency between different aerosol measurements, (2) evaluate a new retrieval of aerosol optical depths (AODs) and inferred surface aerosol concentrations (PM2.5) from the MODIS satellite instrument, and (3) apply this collective information to improve our understanding of aerosol sources. The GEOS‐Chem global chemical transport model (CTM) provides a transfer platform between the different data sets, allowing us to evaluate the consistency between different aerosol parameters observed at different times and …

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Estimation Of Cellular Manufacturing Cost Components Using Simulation And Activity-Based Costing, Paul Savory, Robert Williams Jan 2010

Estimation Of Cellular Manufacturing Cost Components Using Simulation And Activity-Based Costing, Paul Savory, Robert Williams

Department of Industrial and Management Systems Engineering: Faculty Publications

It can be difficult estimating all of the cost components that are attributed to a machined part. This problem is more pronounced when a factory uses group technology manufacturing cells as opposed to a functional or process layout of a job shop. This paper describes how activity-based costing (ABC) concepts can be integrated into a discrete-event simulation model of a U-shaped manufacturing cell producing a part family with four members. The simulation model generates detailed Bills of Activity for each part type and includes specific information about the cost drivers and cost pools. The enhanced model output can be used …

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Mechanical Sensorless Maximum Power Tracking Control For Direct-Drive Pmsg Wind Turbines, Xu Yang, Xiang Gong, Wei Qiao Jan 2010

Mechanical Sensorless Maximum Power Tracking Control For Direct-Drive Pmsg Wind Turbines, Xu Yang, Xiang Gong, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

Wind turbine generators (WTGs) are usually equipped with mechanical sensors to measure wind speed and rotor position for system control, monitoring, and protection. The use of mechanical sensors increases the cost and hardware complexity and reduces the reliability of the WTG systems. This paper proposes a mechanical sensorless maximum power tracking control for wind turbines directly driving permanent magnetic synchronous generators (PMSGs). In the proposed algorithm, the PMSG rotor position is estimated from the measured stator voltages and currents by using a sliding mode observer (SMO). The wind turbine shaft speed is estimated from the PMSG back electromotive force (EMF) …

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Quantitative Evaluation Of The Bim-Assisted Construction Detailed Cost Estimates, Zhigang Shen, Raja R. A. Issa Jan 2010

Quantitative Evaluation Of The Bim-Assisted Construction Detailed Cost Estimates, Zhigang Shen, Raja R. A. Issa

Department of Construction Engineering and Management: Faculty Publications

The increased interest in using Building Information Modeling (BIM) in detailed construction cost estimates calls for methodologies to evaluate the effectiveness of BIM-Assisted Detailed Estimating (BADE) tools in generating detailed construction cost estimates. The focus of this study is on developing a quantified evaluation method to measure the impact of these BADE tools. Further, in order to understand the cognitive details of the estimator, this study also tested and evaluated the impact of the visualization factor and the compound impact of the visualization factor and aggregated calculation factor on the construction cost-estimating process. Two types of BADE tools were tested …

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Examining The Relationship Between The Overexcitabilities And Self-Concepts Of Gifted Adolescents Via Multivariate Cluster Analysis, Anne N. Rinn, Sal Mendaglio, Kathleen Moritz Rudasill, Kand S. Mcqueen Jan 2010

Examining The Relationship Between The Overexcitabilities And Self-Concepts Of Gifted Adolescents Via Multivariate Cluster Analysis, Anne N. Rinn, Sal Mendaglio, Kathleen Moritz Rudasill, Kand S. Mcqueen

Department of Educational Psychology: Faculty Publications

The purpose of this study was to explore the relationship between gifted adolescents’ forms of overexcitabilities and selfconcepts. Clusters of adolescents were formed on the basis of their overexcitabilities, and these clusters of adolescents were then compared with regard to their self-concept scores. Gender differences were also examined. The sample consisted of 379 gifted adolescents, ranging in age from 11 to 16 years of age. Forms of overexcitabilities were measured using the Overexcitabilities Questionnaire–II, and various facets of self-concept were measured using the Self-Description Questionnaire–II. Using cluster analysis, multivariate analysis of variance, and chi-square analysis, results suggested a distinct four-cluster …

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Current And Future Molecular Approaches To Investigate The White Pine Blister Rust Pathosystem, B. A. Richardson, A. K. M. Ekramoddoulah, J.-J. Liu, M.-S. Kim, N. B. Klopfenstein Jan 2010

Current And Future Molecular Approaches To Investigate The White Pine Blister Rust Pathosystem, B. A. Richardson, A. K. M. Ekramoddoulah, J.-J. Liu, M.-S. Kim, N. B. Klopfenstein

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Molecular genetics is proving to be especially useful for addressing a wide variety of research and management questions on the white pine blister rust pathosystem. White pine blister rust, caused by Cronartium ribicola, is an ideal model for studying biogeography, genetics, and evolution because: (1) it involves an introduced pathogen; (2) it includes multiple primary and alternate hosts occurring in large, relatively undisturbed ecosystems; (3) some hosts exhibit endemic resistance; and (4) the disease interaction is long enduring. Molecular techniques are used to investigate population genetics, phylogenetics, hybrids, and proteomics in white pine (Pinus, subgenus Strobus) …

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Generalized Fourier-Feynman Transforms, Convolution Products, And First Variations On Function Space, Seung Jun Chang, Jae Gil Choi, David Skough Jan 2010

Generalized Fourier-Feynman Transforms, Convolution Products, And First Variations On Function Space, Seung Jun Chang, Jae Gil Choi, David Skough

Department of Mathematics: Faculty Publications

In this paper we examine the various relationships that exist among the first variation, the convolution product and the Fourier-Feynman transform for functionals of the form F(x) = f((α1, x), . . . , (αn, x)) with x in a very general function space Ca,b[0,T].

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Thermal Models Of Railroad Wheels And Bearings, Kevin D. Cole, Constantine M. Tarawneh, Arturo A. Fuentes, B. M. Wilson, L. Navarro Jan 2010

Thermal Models Of Railroad Wheels And Bearings, Kevin D. Cole, Constantine M. Tarawneh, Arturo A. Fuentes, B. M. Wilson, L. Navarro

Department of Mechanical and Materials Engineering: Faculty Publications

The rolling surface for railroad wheels can be a heat source that may have an impact on the performance of the wheel bearing. In this study, experimental data from an electrically-heated railroad wheel set is analyzed by constructing thermal models of the wheel set. A steady finite-element model, a steady-analytical model, and a transient lumped-parameter model are discussed. Model parameters are determined from careful comparisons with the experimental data. The lumped-parameter model given here is intended as a simple predictive tool for determining when wheel heating caused by rail operations will have an impact on bearing temperature. The model parameters …

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Force–Frequency Effect Of Thickness Mode Langasite Resonators, Haifeng Zhang, Joseph A. Turner, Jiashi Yang, John A. Kosinski Jan 2010

Force–Frequency Effect Of Thickness Mode Langasite Resonators, Haifeng Zhang, Joseph A. Turner, Jiashi Yang, John A. Kosinski

Department of Mechanical and Materials Engineering: Faculty Publications

Langasite resonators are of recent interest for a variety of applications because of their good temperature behavior, good piezoelectric coupling, low acoustic loss and high Q factor. The force–frequency effect describes the shift in resonant frequency a resonator experiences due to the application of a mechanical load. A clear understanding of this effect is essential for many design applications such as pressure sensors. In this article, the frequency shift is analyzed theoretically and numerically for thin, circular langasite plates subjected to a pair of diametrical forces. In addition, the sensitivity of the force–frequency effect is analyzed with respect to the …

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