Suppression of vortex channeling in meandered YBa2Cu3O7-d grain boundaries

We report on the in-plane magnetic field (H) dependence of the critical current density (Jc) in meandered and planar single grain boundaries (GBs) isolated in YBa2Cu3O7-d (YBCO) coated conductors. The Jc(H)properties of the planar GB are consistent with those previously seen in single GBs of YBCO films grown on SrTiO3 bi-crystals. In the straight boundary a characteristic flux channeling regime when H is oriented near the GB plane, associated with a reduced Jc, is seen. The meandered GB does not show vortex channeling since it is not possible for a sufficient length of vortex line to lie within it.Comment: Submitted to AP

Predicting House Prices with Spatial Dependence: A Comparison of Alternative Methods

This paper compares alternative methods for taking spatial dependence into account in house price prediction. We select hedonic methods that have been reported in the literature to perform relatively well in terms of ex-sample prediction accuracy. Because differences in performance may be due to differences in data, we compare the methods using a single data set. The estimation methods include simple OLS, a two-stage process incorporating nearest neighbors’ residuals in the second stage, geostatistical, and trend surface models. These models take into account submarkets by adding dummy variables or by estimating separate equations for each submarket. Based on data for approximately 13,000 transactions from Louisville, Kentucky, we conclude that a geostatistical model with disaggregated submarket variables performs best.

Spatial Dependence, Housing Submarkets, and House Prices

This paper compares the impacts of alternative models of spatial dependence on the accuracy of house price predictions in a mass appraisal context. Explicit modeling of spatial dependence is characterized as a more fluid approach to defining housing submarkets. This approach allows the relevant “submarket” to vary from house to house and for transactions involving other dwellings in each submarket to have varying impacts depending on distance. We compare the predictive ability of different specifications of both geostatistical and lattice models as well as a simpler model based on submarkets with fixed boundaries. We conclude that – for our data – no spatial statistics method does as well in terms of predictive ability as a simple OLS model that includes a series of dummy variables defining submarkets. However, of the spatial statistics methods, geostatistical models provide more accurate predictions than lattice models. We argue that this is due to the fact that the kriging procedure used to make predictions in a geostatistical framework directly incorporates spatial information about nearby properties. That is not possible in a lattice framework due to the reliance on a matrix of weights that incorporates relationships only for the sample of properties that transact.spatial dependence; hedonic price models; geostatistical models; lattice models; mass appraisal; housing submarkets

3D EDX microanalysis by FIB-SEM: Elemental quantification enhancement

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 - August 2, 201

FIB-SEM Nanotomography in Materials and Life Science at EPFL

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 - August 5, 201

Multivariate Statistical Analysis tool for the interpretation and the quantification of hyperspectral data: application to 3D EDX/FIB images

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 - August 2, 201

Superconducting magnesium diboride films with Tc \approx 24K grown by pulsed laser deposition with in-situ anneal

Thin superconducting films of magnesium diboride (MgB2) with Tc \approx 24K were prepared on various oxide substrates by pulsed laser deposition (PLD) followed by an in-situ anneal. A systematic study of the influence of various in-situ annealing parameters shows an optimum temperature of about 600C in a background of 0.7 atm. of Ar/4%H2 for layers consisting of a mixture of magnesium and boron. Contrary to ex-situ approaches (e.g. reacting boron films with magnesium vapor at 900C), these films are processed below the decomposition temperature of MgB2. This may prove enabling in the formation of multilayers, junctions, and epitaxial films in future work. Issues related to the improvement of these films and to the possible in-situ growth of MgB2 at elevated temperature are discussed.Comment: 5 pages, 4 figure

Focused Ion Beam Nano-Tomography Using Different Detectors

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7-August 11, 201