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Lanthanum Doped Multiferroic Dyfeo3: Structural And Magnetic Properties, Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou 2010 University of Wollongong

Lanthanum Doped Multiferroic Dyfeo3: Structural And Magnetic Properties, Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

Lanthanum doped multiferroic DyFeO3 was synthesized by solid state reaction. X-ray diffraction and refinement show that the lattice parameters of Dy1−xLaxFeO3 increase linearly with the La content. Raman spectroscopy reveals that the short-range force constant in Dy1−xLaxFeO3 is decreased by La3+ ion substitution. The spin reorientation phase transition temperature (TSRPT) is observed to decrease along with the doping level. The antiferromagnetic ordering temperature TN of Fe3+ ions is depressed with increasing doping level. Both decreasing TSRPT and decreasing TN indicate that Fe–Dy ...


Magnetic Properties Of Ho2fe17-Xmnx - Influence Of Mn Substitution, Jianli Wang, Stewart J. Campbell, A J Studer, S J. Kennedy, Rong Zeng 2010 University of Wollongong

Magnetic Properties Of Ho2fe17-Xmnx - Influence Of Mn Substitution, Jianli Wang, Stewart J. Campbell, A J Studer, S J. Kennedy, Rong Zeng

Australian Institute for Innovative Materials - Papers

The structural and magnetic properties of Ho2Fe17−xMnx (x=0-5) have been investigated by x-ray diffraction, Mössbauer spectroscopy and DC magnetization measurements (0-5 T) over the temperature range 4.5-350 K. Similar to other ferrimagnetic R2Fe17-xMnx systems, the unit cell volume generally increases with Mn content other than for low Mn values where a slight maximum is detected around x ∼ 0.5. The nature of the magnetic phase transitions around TC is shown by Arrot plot analysis to be second order for all samples. The Curie temperature remains essentially ...


Superconducting Properties Of Carbonaceous Chemical Doped Mgb2, Wenxian Li, S X. Dou 2010 University of Wollongong

Superconducting Properties Of Carbonaceous Chemical Doped Mgb2, Wenxian Li, S X. Dou

Australian Institute for Innovative Materials - Papers

The discovery of superconductivity in magnesium diboride (MgB2: 39 K, in January 2001) (Nagamatsu et al., 2001) has generated enormous interest and excitement in the superconductivity community and the world in general, but especially among researchers into superconductivity in non-oxide and boron related compounds.


Folic Acid Source, Usual Intake, And Folate And Vitamin B-12 Status In Us Adults: National Health And Nutrition Examination Survey (Nhanes) 2003–2006, Quanhe Yang, Mary E. Cogswell, Heather C. Hamner, Alicia L. Carriquiry, Christine M. Pfeiffer, Robert J. Berry 2010 Centers for Disease Control and Prevention

Folic Acid Source, Usual Intake, And Folate And Vitamin B-12 Status In Us Adults: National Health And Nutrition Examination Survey (Nhanes) 2003–2006, Quanhe Yang, Mary E. Cogswell, Heather C. Hamner, Alicia L. Carriquiry, Christine M. Pfeiffer, Robert J. Berry

Statistics Publications

Background: US adults have access to multiple sources of folic acid. The contribution of these sources to usual intakes above the tolerable upper intake level (UL) (1000 ug/d) and to folate and vitamin B-12 status is unknown. Objective: The objective was to estimate usual folic acid intake above the UL and adjusted serum and red blood cell folate, vitamin B-12, methylmalonic acid, and homocysteine concentrations among US adults by 3 major folic acid intake sources - enriched cereal-grain products (ECGP), ready-to-eat cereals (RTE), and supplements (SUP) - categorized into 4 mutually exclusive consumption groups. Design: We used data from the National ...


A K-Mean-Directions Algorithm For Fast Clustering Of Data On The Sphere, Ranjan Maitra, Ivan Peter Ramler 2010 Iowa State University

A K-Mean-Directions Algorithm For Fast Clustering Of Data On The Sphere, Ranjan Maitra, Ivan Peter Ramler

Statistics Publications

A k-means-type algorithm is proposed for efficiently clustering data constrained to lie on the surface of a p-dimensional unit sphere, or data that are mean-zero-unit-variance standardized observations such as those that occur when using Euclidean distance to cluster time series gene expression data using a correlation metric. We also provide methodology to initialize the algorithm and to estimate the number of clusters in the dataset. Results from a detailed series of experiments show excellent performance, even with very large datasets. The methodology is applied to the analysis of the mitotic cell division cycle of budding yeast dataset of ...


Sustainability Of Glyphosate-Based Weed Management: The Benchmark Study, Michael D. Owen, Philip M. Dixon, David R. Shaw, Stephen C. Weller, Bryan G. Young, Robert G. Wilson, David L. Jordan 2010 Iowa State University

Sustainability Of Glyphosate-Based Weed Management: The Benchmark Study, Michael D. Owen, Philip M. Dixon, David R. Shaw, Stephen C. Weller, Bryan G. Young, Robert G. Wilson, David L. Jordan

Statistics Publications

One key to improved global crop production efficiency is the effective management of weeds, which are ranked as the number one crop pest by a majority of farmers1. This is no great surprise, as weeds are constantly evolving within the man-caused agroecosystems by adapting to high selection pressures imposed by crop production practices and, importantly, developing resistance to herbicides. Genetically engineered (GE) herbicide resistant (HR) crops facilitate better weed management and thus improved yields and more efficient use of resources, while minimizing risks to the environment (e.g., soil erosion). Since the commercial introduction of glyphosate resistant (GR) crops in ...


Simulating Data To Study Performance Of Finite Mixture Modeling And Clustering Algorithms, Ranjan Maitra, Volodymyr Melnykov 2010 Iowa State University

Simulating Data To Study Performance Of Finite Mixture Modeling And Clustering Algorithms, Ranjan Maitra, Volodymyr Melnykov

Statistics Publications

A new method is proposed to generate sample Gaussian mixture distributions according to prespecified overlap characteristics. Such methodology is useful in the context of evaluating performance of clustering algorithms. Our suggested approach involves derivation of and calculation of the exact overlap between every cluster pair, measured in terms of their total probability of misclassification, and then guided simulation of Gaussian components satisfying prespecified overlap characteristics. The algorithm is illustrated in two and five dimensions using contour plots and parallel distribution plots, respectively, which we introduce and develop to display mixture distributions in higher dimensions. We also study properties of the ...


Kentucky Water Resources Research Institute Annual Technical Report Fy 2009, Kentucky Water Resources Research Institute, University of Kentucky 2010 University of Kentucky

Kentucky Water Resources Research Institute Annual Technical Report Fy 2009, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Annual Technical Reports

The 2009 Annual Technical Report for Kentucky consolidates reporting requirements of the Section 104(b) base grant award into a single document that includes: 1) a synopsis of each research project conducted with grant funds during the period, 2) citations for related publications, reports, and presentations, 3) a description of information transfer activities, 4) a summary of student support during the reporting period, and 5) notable awards and achievements during the year.


Suppression Of The Critical Temperature For Superfluidity Near The Mott Transition, S Trotzky, L Pollet, F Gerbier, U Schnorrberger, I Bloch, Nikolai Prokof'ev, Boris Svistunov, M Troyer 2010 University of Massachusetts - Amherst

Suppression Of The Critical Temperature For Superfluidity Near The Mott Transition, S Trotzky, L Pollet, F Gerbier, U Schnorrberger, I Bloch, Nikolai Prokof'ev, Boris Svistunov, M Troyer

Physics Department Faculty Publication Series

Ultracold atomic gases in optical lattices have proven to be a controllable, tunable and clean implementation of strongly interacting quantum many-body systems. An essential prospect for such quantum simulators is their ability to map out the phase diagram of fundamental many-body model Hamiltonians. However, the results need to be validated first for representative benchmark problems through state-of-the-art numerical methods of quantum many-body theory. Here we present the first ab initio comparison between experiments and quantum Monte Carlo simulations for strongly interacting Bose gases on a lattice for large systems (up to particles). The comparison enables thermometry for the interacting quantum ...


Automatic Readability Assessment, Lijun Feng 2010 The Graduate Center, City University of New York

Automatic Readability Assessment, Lijun Feng

All Dissertations, Theses, and Capstone Projects

We describe the development of an automatic tool to assess the readability of text documents. Our readability assessment tool predicts elementary school grade levels of texts with high accuracy. The tool is developed using supervised machine learning techniques on text corpora annotated with grade levels and other indicators of reading difficulty. Various independent variables or features are extracted from texts and used for automatic classification. We systematically explore different feature inventories and evaluate the grade-level prediction of the resulting classifiers. Our evaluation comprises well-known features at various linguistic levels from the existing literature, such as those based on language modeling ...


On The Convergence Of Greedy Algorithms For Initial Segments Of The Haar Basis, S J. Dilworth, E Odell, TH Schlumprecht, Andras Zsak 2010 University of South Carolina - Columbia

On The Convergence Of Greedy Algorithms For Initial Segments Of The Haar Basis, S J. Dilworth, E Odell, Th Schlumprecht, Andras Zsak

Faculty Publications

We consider the X-Greedy Algorithm and the Dual Greedy Algorithm in a finite-dimensional Banach space with a strictly monotone basis as the dictionary. We show that when the dictionary is an initial segment of the Haar basis in Lp[0, 1] (1< p < 1) then the algorithms terminate after finitely many iterations and that the number of iterations is bounded by a function of the length of the initial segment. We also prove a more general result for a class of strictly monotone bases.


Toward A Whole-Landscape Approach For Sustainable Land Use In The Tropics, R. DeFries, C. Rosenzweig 2010 Columbia University

Toward A Whole-Landscape Approach For Sustainable Land Use In The Tropics, R. Defries, C. Rosenzweig

NASA Publications

Increasing food production and mitigating climate change are two primary but seemingly contradictory objectives for tropical landscapes. This special feature examines synergies and trade-offs among these objectives. Four themes emerge from the papers: the important roles of both forest and agriculture sectors for climate mitigation in tropical countries; the minor contribution from deforestation-related agricultural expansion to overall food production at global and continental scales; the opportunities for synergies between improved food production and reductions in greenhouse gas emissions through diversion of agricultural expansion to already-cleared lands, improved soil, crop, and livestock management, and agroforestry; and the need for targeted policy ...


Toward Establishing A Realistic Benchmark For Airframe Noise Research: Issues And Challenges, Mehdi R. Khorrami 2010 NASA Langley Research Center

Toward Establishing A Realistic Benchmark For Airframe Noise Research: Issues And Challenges, Mehdi R. Khorrami

NASA Publications

The availability of realistic benchmark configurations is essential to enable the validation of current Computational Aeroacoustic (CAA) methodologies and to further the development of new ideas and concepts that will foster the technologies of the next generation of CAA tools. The selection of a real-world configuration, the subsequent design and fabrication of an appropriate model for testing, and the acquisition of the necessarily comprehensive aeroacoustic data base are critical steps that demand great care and attention. In this paper, a brief account of the nose landing-gear configuration, being proposed jointly by NASA and the Gulfstream Aerospace Company as an airframe ...


Automation For Task Analysis Of Next Generation Air Traffic Management Systems, Maricel Medina, Lance Sherry, Michael Feary 2010 George Mason University

Automation For Task Analysis Of Next Generation Air Traffic Management Systems, Maricel Medina, Lance Sherry, Michael Feary

NASA Publications

The increasing span of control of Air Traffic Control enterprise automation (e.g. Flight Schedule Monitor, Departure Flow Management), along with lean-processes and pay-for-performance business models, has placed increased emphasis on operator training time and error rates. There are two traditional approaches to the design of human–computer interaction (HCI) to minimize training time and reduce error rates: (1) experimental user testing provides the most accurate assessment of training time and error rates, but occurs too late in the development cycle and is cost prohibitive, (2) manual review methods (e.g. cognitive walk through) can be used earlier in the ...


Remote Sensing Of Phytoplankton Pigment Distribution In The United States Northeast Coast, Xiaoju Pan, Antonio Mannino, Mary E. Russ, Stanford B. Hooker, Lawrence Harding 2010 NASA Goddard Space Flight Center

Remote Sensing Of Phytoplankton Pigment Distribution In The United States Northeast Coast, Xiaoju Pan, Antonio Mannino, Mary E. Russ, Stanford B. Hooker, Lawrence Harding

NASA Publications

Phytoplankton pigments constitute many more compounds than chlorophyll a that can be applied to study phytoplankton diversity, populations, and primary production. In this study, field measurements were applied to develop ocean color satellite algorithms of phytoplankton pigments from in-water radiometry measurements. The match-up comparisons showed that the satellite-derived pigments from our algorithms agree reasonably well (e.g. 30–55% of uncertainty for SeaWiFS and 37–50% for MODIS-Aqua) to field data, with better agreement (e.g. 30–38% of uncertainty for SeaWiFS and 39–44% for MODIS-Aqua) for pigments abundant in diatoms. The seasonal and spatial variations of satellite-derived phytoplankton ...


Thermal Expansion Of Vacuum Plasma Sprayed Coatings, S.V. Raj, A. Palczer 2010 NASA Glenn Research Center

Thermal Expansion Of Vacuum Plasma Sprayed Coatings, S.V. Raj, A. Palczer

NASA Publications

Metallic Cu–8%Cr, Cu–26%Cr, Cu–8%Cr–1%Al, NiAl and NiCrAlY monolithic coatings were fabricated by

vacuum plasma spray deposition processes for thermal expansion property measurements between 293

and 1223 K. The corrected thermal expansion, (∆L/L0)thermal, varies with the absolute temperature, T, as

( ∆L ) = A(T-293)3 + B(T-293)2 + C(T -293) + D

(L0)thermal

where A, B, C and D are regression constants. Excellent reproducibility was observed for all of the

coatings except for data obtained on the Cu–8%Cr and Cu–26%Cr coatings in the ...


Test Method Variability In Slow Crack Growth Properties Of Sealing Glasses, J. Salem, R. Tandon 2010 NASA Glenn Research Center

Test Method Variability In Slow Crack Growth Properties Of Sealing Glasses, J. Salem, R. Tandon

NASA Publications

The crack growth properties of several sealing glasses were measured by using constant stress rate testing in ~2% and 95% RH (relative humidity). Crack growth parameters measured in high humidity are systematically smaller (n and B) than those measured in low humidity, and crack velocities for dry environments are ~100 x lower than for wet environments. The crack velocity is very sensitivity to small changes in RH at low RH. Biaxial and uniaxial stress states produced similar parameters. Confidence intervals on crack growth parameters that were estimated from propagation of errors solutions were comparable to those from Monte Carlo simulation ...


Evaluation Of Shortwave Infrared Atmospheric Correction For Ocean Color Remote Sensing Of Chesapeake Bay, P. Jeremy Werdell, Bryan A. Franz, Sean W. Bailey 2010 NASA Goddard Space Flight Center

Evaluation Of Shortwave Infrared Atmospheric Correction For Ocean Color Remote Sensing Of Chesapeake Bay, P. Jeremy Werdell, Bryan A. Franz, Sean W. Bailey

NASA Publications

The NASA Moderate Resolution Imaging Spectroradiometer onboard the Aqua platform (MODIS-Aqua) provides a viable data stream for operational water quality monitoring of Chesapeake Bay. Marine geophysical products from MODIS-Aqua depend on the efficacy of the atmospheric correction process, which can be problematic in coastal environments. The operational atmospheric correction algorithm for MODISAqua requires an assumption of negligible near-infrared water-leaving radiance, nLw(NIR). This assumption progressively degrades with increasing turbidity and, as such, methods exist to account for non-negligible nLw(NIR) within the atmospheric correction process or to use alternate radiometric bands where the assumption is satisfied, such as ...


Lower Semimodular Inverse Semigroups, Ii, Peter R. Jones, Kyeong Hee Cheong 2010 Marquette University

Lower Semimodular Inverse Semigroups, Ii, Peter R. Jones, Kyeong Hee Cheong

Mathematics, Statistics and Computer Science Faculty Research and Publications

The authors’ description of the inverse semigroups S for which the lattice ℒℱ(S) of full inverse subsemigroups is lower semimodular is used to describe those for which (a) the lattice ℒ(S) of all inverse subsemigroups or (b) the lattice �o(S) of convex inverse subsemigroups has that property. In each case, we show that this occurs if and only if the entire lattice is a subdirect product of ℒℱ(S) with ℒ(E S ), or �o(E S ), respectively, where E S is the semilattice of idempotents of S; a simple necessary and sufficient condition is found for ...


Targeting Base Excision Repair Suggests A New Therapeutic Strategy Of Fludarabine For The Treatment Of Chronic Lymphocytic Leukemia, A. D. Bulgar, M. Snell, J. R. Donze, E. B. Kirkland, Lan Li, Shuming Yang, Yan Xu, S. L. Gerson, Lili Liu 2010 Cleveland State University

Targeting Base Excision Repair Suggests A New Therapeutic Strategy Of Fludarabine For The Treatment Of Chronic Lymphocytic Leukemia, A. D. Bulgar, M. Snell, J. R. Donze, E. B. Kirkland, Lan Li, Shuming Yang, Yan Xu, S. L. Gerson, Lili Liu

Chemistry Faculty Publications

No abstract provided.


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