Rapidly Quenched Kosterlitz-Thouless Superfluid Transitions

Rapidly quenched Kosterlitz-Thouless (KT) superfluid transitions are studied by solving the Fokker-Planck equation for the vortex-pair dynamics in conjunction with the KT recursion relations. Power-law decays of the vortex density at long times are found, and the results are in agreement with a scaling proposal made by Minnhagen and co-workers for the dynamical critical exponent. The superfluid density is strongly depressed after a quench, with the subsequent recovery being logarithmically slow for starting temperatures near T$_{KT}$. No evidence is found of vortices being ''created'' in a rapid quench, there is only decay of the existing thermal vortex pairs.Comment: 4 pages, 5 figures, revtex4, version accepted for PR

Vortex Core Size in 3^3He-4^4He films with Monolayer Superfluid 4^4He

The superfluid transition of $^3$He-$^4$He mixture films adsorbed on alumina powder is studied, with a $^4$He superfluid coverage near one layer. With up to 1.3 layers of $^3$He added, the transition becomes strongly broadened, indicating a linear increase in the vortex core size for $^3$He coverages below one layer. Annealing of the sample mixture at 4.2 K is found to be critically important in ensuring a homogeneous film across the porous substrate.Comment: 2 pages, 2 figures, accepted for LT22 Conference Proceedings, Physica

Performance of epoxy-coated reinforcement in Iowa bridge decks

Concrete bridge decks subjected to corrosive environment, due to the application of de-icing chemical, could deteriorate at a rapid rate. In an effort to minimize corrosion of the reinforcement and the corresponding delaminations and spalls, the Iowa Department of Transportation (IADOT) started using epoxy-coated rebars (ECR) in the top mat of reinforcing around 1976 and in both mats about 10 years later. The ultimate objective of this research was to determine the impact of deck cracking on durability and estimate the remaining functional service life of a bridge deck. The overall objectives of this work were obtained by conducting a literature review, visually inspecting several bridge decks, collecting and sampling test cores from cracked and uncracked areas of bridge decks, determining the extent to which epoxy coated rebars deteriorate at the site of cracks, and evaluating the impact of cracking on service life. Overall, 81 bridges constructed with ECR were sampled. Fick\u27s Second Law was applied in this study to estimate the time required to reach the corrosive threshold of chloride concentration at the rebar level i.e., the time length of the corrosion initiation stage. No signs of corrosion were observed on the rebars collected from uncracked locations. Rebars that had surface corrosion undercutting the epoxy coating were those collected from cores that were taken from cracked locations. In general, no delaminations or spalls were found on the decks where these bars were cored. The surface chloride concentration at 1/2 below the deck surface and the diffusion constant were found to be 14.0 lb/yd3 and 0.05 in 2/yr respectively. The predicted service life for Iowa bridge decks constructed with ECR was calculated to be approximately between 53 and 141 years. This illustrates that ECR can significantly extend the service life when compared to bridges constructed with black rebars

3D Alchemy: a guide to 3D realistic computer graphics

Last year, many films and commercials took advantage of computer technology to create astonishing 3D animations. Examples such as the Listerine commercial series, the NBA logo on TV, and the Chip & Pepper TV cartoon, featured unique and vibrant computer images. Among the various animations, some were made by high end computer systems, but some simply by personal computers. Small, fast, and more capable personal computers are now performing professional-level video production roles and, in fact, they are a staple of many feature film productions and broadcast television facilities

Using SVM with Financial Statement Analysis for Prediction of Stocks

At present, there are many technical analyses for prediction in stock market. However, the technical indices are fluctuated with the quantity of stock exchanges. The financial indices are more reliable, nonvolatile and valid compared with the technical indices. In this paper, we propose an original and universal method by using SVM with financial statement analysis for prediction of stocks. We applied the SVM to construct the prediction model and select Gaussian radial basis function (RBF) as the kernel function. The experimental results show our method not only improve the accuracy rate, but also meet the different stockholders’ expectations