Prediction of design water level due to storm surge at teh Seogwipo coastal zone in Korea

Seogwipo coastal region is known to develop coast tourist attractions and expand its harbor facilities, but this region is also more likely to get damaged by typhoons since it is affected by most of the typhoons coming into the Korean Peninsula. This study comprehended the characteristics of Jeju Island coastal areas by analyzing severe weather elements like a typhoon, and particularly reviewed design water levels by storm surge in Seogwipo Harbor. The design water level was calculated on the basis of frequency analysis results regarding extreme water levels, tidal residuals per hour and observed surges and numerical simulation-based surge heights in case of a typhoon attack, and this study also suggested problems that rapid climatic change aspects cannot be reflected recently. To solve such a problem, it is required to constantly maintain the related data and apply high-degree stormy surge numerical simulations-based plans to the present work

Single-filament Composite MgB2/SUS Ribbons by Powder-In-Tube Process

We report the successful fabrication of single-filament composite MgB2/SUS ribbons, as an ultra-robust conductor type, employing the powder-in-tube (PIT) process, by swaging and cold rolling only. The remarkable transport critical current (Ic) of the non-sintered MgB2/SUS ribbon has observed, as an unexpected result. Transport critical currents Ic ~ 316 A at T = 4.2 K and Ic ~ 82 A at T = 20 K were observed at self-field, for the non-sintered composite MgB2/SUS ribbon. In addition, the persistent current density Jp values, that were estimated by Bean formula, were more than ~ 7  105 A/cm2 at T = 5 K, and ~ 1.2  105 A/cm2 at T = 30 K, for the sintered composite MgB2/SUS ribbon, at H = 0 G.Comment: 10 pages, 4 figure

Probing R-violating top quark decays at the NLC

We examine the possibility of observing exotic top quark decays via $R$-Parity violating SUSY interactions in $e^+e^-$ collisions at \sqrt{s = 500 GeV. We present cross-sections for $t\bar t$ production followed by the subsequent decay of either the $t$ or $\overline{t}$ via the $R$-Parity violating interaction while the other undergoes the SM decay. We discuss kinematic cuts that allow the exotic SUSY decays to be detected over standard model backgrounds. Discovery limits for $R$-Parity violating couplings in the top sector are presented assuming an integrated luminosity of $100 fb^{-1}$.Comment: 9 LaTeX pages, 3 PS figure

Photonic crystal cavity-based intensity modulation for integrated optical frequency comb generation

A simple scheme to generate an integrated, nanoscale optical frequency comb (OFC) is numerically studied. In this study, all optical intensity modulators based on photonic crystal (PhC) cavities are cascaded both in series and parallel. By adjusting the modulation parameters, such as the repetition rate, phase, and coupling efficiency of the modulating wave, it is possible to produce combs with a variety of different characteristics. Unique to PhC intensity modulators, in comparison with standard lithium niobate modulators, is the ability to control the amplitude of the light via a cavity rather than controlling the phase through one arm of a Mach–Zehnder interferometer. This opens up modulation-based OFC generation to new possibilities in both nanoscale operation and cavity-based schemes

Electromagnetically induced transparency in multi-level cascade scheme of cold rubidium atoms

We report an experimental investigation of electromagnetically induced transparency in a multi-level cascade system of cold atoms. The absorption spectral profiles of the probe light in the multi-level cascade system were observed in cold Rb-85 atoms confined in a magneto-optical trap, and the dependence of the spectral profile on the intensity of the coupling laser was investigated. The experimental measurements agree with the theoretical calculations based on the density matrix equations of the rubidium cascade system.Comment: 9 pages, 5 figure

Flocculation onset in Saccharomyces cerevisiae: effect of ethanol, heat and osmotic stress

Aims: To examine the effect of different stress conditions on the onset of flocculation in an ale-brewing strain, Saccharomyces cerevisiae NCYC 1195. Methods and Results: Flocculation was evaluated using the method of Soares, E.V. and Vroman, A. [Journal of Applied Microbiology (2003) 95, 325]; plasma membrane integrity was accessed using propidium iodide and the staining of the yeast cell wall was performed using calcofluor white M2R. Cells in exponential phase of growth were subjected to different stress conditions. The addition of 1%, 3% and 5% (v/v) ethanol, 1% and 3% (v/v) isopropanol or a brief heat shock (52ºC, 5 min), did not induce an early flocculation phenotype when compared with control cells. The addition of 10% (v/v) ethanol, a continuous mild heat-stress (37ºC) or an osmotic stress (0.5 or 1 mol l-1 of NaCl) did not induce a flocculent phenotype. Conclusions: Flocculation seems not to be induced as a response to different chemical (ethanol and isopropanol) and physical (heat and osmotic) stress conditions. Conversely, osmotic and ethanol [10% (v/v)] stress, as well as a continuous mild heat shock (37ºC), have a negative impact on the phenotype expression of flocculation. Significance and Impact of the Study: The findings reported here contribute to the elucidation of the control of yeast flocculation. This information might be useful to the brewing industry, as the time when the onset of flocculation occurs can determine the fermentation performance and the beer quality, as well as in other biotechnological industries where flocculation can be used as a cell separation process.ERASMUS; ISEP (Portugal)

Hexatic-Herringbone Coupling at the Hexatic Transition in Smectic Liquid Crystals: 4-ϵ\epsilon Renormalization Group Calculations Revisited

Simple symmetry considerations would suggest that the transition from the smectic-A phase to the long-range bond orientationally ordered hexatic smectic-B phase should belong to the XY universality class. However, a number of experimental studies have constantly reported over the past twenty years "novel" critical behavior with non-XY critical exponents for this transition. Bruinsma and Aeppli argued in Physical Review Letters {\bf 48}, 1625 (1982), using a $4-\epsilon$ renormalization-group calculation, that short-range molecular herringbone correlations coupled to the hexatic ordering drive this transition first order via thermal fluctuations, and that the critical behavior observed in real systems is controlled by a `nearby' tricritical point. We have revisited the model of Bruinsma and Aeppli and present here the results of our study. We have found two nontrivial strongly-coupled herringbone-hexatic fixed points apparently missed by those authors. Yet, those two new nontrivial fixed-points are unstable, and we obtain the same final conclusion as the one reached by Bruinsma and Aeppli, namely that of a fluctuation-driven first order transition. We also discuss the effect of local two-fold distortion of the bond order as a possible missing order parameter in the Hamiltonian.Comment: 1 B/W eps figure included. Submitted to Physical Review E. Contact: [email protected]

Probing Topcolor-Assisted Technicolor from Top-Charm Associated Production at LHC

We propose to probe the topcolor-assisted technicolor (TC2) model from the top-charm associated productions at the LHC, which are highly suppressed in the Standard Model. Due to the flavor-changing couplings of the top quark with the scalars (top-pions and top-Higgs) in TC2 model, the top-charm associated productions can occur via both the s-channel and t-channel parton processes by exchanging a scalar field at the LHC. We examined these processes through Monte Carlo simulation and found that they can reach the observable level at the LHC in quite a large part of the parameter space of the TC2 model.Comment: Version to appear in PRD (Rapid Communication

Fabrication of high quality plan-view TEM specimens using the focused ion beam

We describe a technique using a focused ion beam instrument to fabricate high quality plan-view specimens for transmission electron microscopy studies. The technique is simple, site-specific and is capable of fabricating multiple large, >100 μm2 electron transparent windows within epitaxially-grown thin films. A film of La0.67Sr0.33MnO3 is used to demonstrate the technique and its structural and functional properties are surveyed by high resolution imaging, electron spectroscopy, atomic force microscopy and Lorentz electron microscopy. The window is demonstrated to have good thickness uniformity and a low defect density that does not impair the film’s Curie temperature. The technique will enable the study of in–plane structural and functional properties of a variety of epitaxial thin film systems

Anisotropic superconductivity mediated by phonons in layered compounds with weak screening effect

Anisotropic pairing interactions mediated by phonons are examined in layer systems. It is shown that the screening effects become weaker when the layer spacing increases. Then the anisotropic components of the pairing interactions increase with the screening length since the momentum dependence changes. As a result, various types of anisotropic superconductivity occur depending on the parameter region. For example, p-wave superconductivity occurs when the short-range part of Coulomb repulsion is strong and the layer spacing is large. Two kinds of inter-layer pairing may occur when the layer spacing is not too large. Although the phonon contribution to the d-wave pairing interaction is weaker than the p-wave interaction, it increases with the layer spacing. Relevance of the present results to organic superconductors, high-T_c cuprates, and Sr_2RuO_4 is discussed.Comment: 8 pages, 5 figures, (Latex, revtex.sty, epsf.sty