Investigate the impacts of assimilating satellite rainfall estimates on rainstorm forecast over southwest United States

Using the MM5-4DVAR system, a monsoon rainstorm case over southern Arizona (5-6 August 2002) was investigated for the influence of assimilating satellite rainfall estimates on precipitation forecasts. A set of numerical experiments was conducted with multiple configurations including using 20-km or 30-km grid distances and none or 3-h or 6-h assimilation time windows. Results show that satellite rainfall assimilation can improve the rainstorm-forecasting pattern and amount to some extent. The minimization procedure of 4DVAR is sensitive to model spatial resolution and the assimilation time window. The 3-h assimilation window with hourly rainfall data works well for the 6-h forecast, and for 12-h or longer forecasts, a 6-h assimilation window will be requested. Copyright 2004 by the American Geophysical Union

Hadron pair photoproduction within the Veneziano model

We first suppose that low-energy hadron pair photoproduction reactions gamma(*) gamma(*) -> h h-bar are dominated by s-channel resonance contributions. Their normalization is then calculated by their correspondence with the Reggeon term in the Regge parametrization of the gamma h total cross sections. For the case of p p-bar, we make use of the measured gamma p total cross section, and for the case of K+K-, we make use of the corresponding total cross section that is estimated using Regge factorization. For hadrons that have no such data, we can only provide rough estimation based on the additive quark rule. As an effective approach that is convenient and parameter-free, we adopt the Veneziano model in the simplest form. The model is only applicable to the region of low centre-of-mass energy. When the transverse momentum is large, perturbative QCD takes over, whereas in the Regge region, it is known that the Regge pole picture fails in photoproduction. Despite the shortcomings of the model, we find that the parameter-free amplitudes offer a sound description of the data at hand.Comment: 24 pages, 11 figure

A Generalization of Aztec Diamond Theorem, Part II

The author gave a proof of a generalization of the Aztec diamond theorem for a family of $4$-vertex regions on the square lattice with southwest-to-northeast diagonals drawn in (Electron. J. Combin., 2014) by using a bijection between tilings and non-intersecting lattice paths. In this paper, we use Kuo graphical condensation to give a new proof.Comment: 11 pages and 7 figure

Prevalence of rear seat belt use among pregnant women in a suburban area of Japan

学位記番号：保博甲122 This is the accepted version of the following article: FULL CITE, which has been published in final form at [https://doi.org/10.1111/jog.13468]

Proof of Blum's conjecture on hexagonal dungeons

Matt Blum conjectured that the number of tilings of the Hexagonal Dungeon of sides $a,\ 2a,\ b,\ a,\ 2a,\ b$ (where $b\geq 2a$) is $13^{2a^2}14^{\lfloor\frac{a^2}{2}\rfloor}$ (J. Propp, New Perspectives in Geometric Combinatorics, Cambridge University Press, 1999). In this paper we present a proof for this conjecture using Kuo's Graphical Condensation Theorem (E. Kuo, Applications of Graphical Condensation for Enumerating Matchings and Tilings, Theoretical Computer Science, 2004).Comment: 30 page

Influences of Model Parameterization Schemes on the Response of Rainfall to Soil Moisture in the Central United States

The sensitivities of soil moisture impacts on summer rainfall in the central United States to different commonly used cumulus parameterization and surface flux schemes are examined using the PSU-NCAR MMS under different atmospheric and soil moisture conditions. The cumulus convection schemes used are the Kuo and Grell parameterization schemes, while the surface-moisture flux schemes used are the aerodynamic formulation and the Simple Biosphere (SiB) Model. Results show that a transient increase in soil moisture enhanced total rainfall over the simulation domain. The increase in soil moisture enhanced local rainfall when the lower atmosphere was thermally unstable and relatively dry, but it decreased the rainfall when the atmosphere was humid and lacked sufficient thermal forcing to initiate deep convection. Soil moisture impacts were noticeably stronger for the Kuo scheme, which simulated lighter peak rainfall, than those for the Grell scheme, which simulated heavier peak rainfall. The greater sensitivity to soil moisture exhibited by the Kuo scheme than either the Grell or explicit scheme implies that it exaggerated the role of soil moisture. This difference was related to how each scheme partitioned rainfall between convective and stable forms, and possibly to each scheme\u27s closure assumptions. Adding details to the surface-moisture flux schemes had a secondary influence on soil moisture impacts on rainfall within a 24-h period