Reexamining charmless B\to PV decays in QCD factorization approach

Using the QCD factorization approach, we reexamine the two-body hadronic charmless $B$-meson decays to final states involving a pseudoscalar~($P$) and a vector~($V$) meson, with inclusion of the penguin contractions of spectator-scattering amplitudes induced by the $b\to D g^\ast g^\ast$~(where $D=d$ or $s$, and $g^\ast$ denotes an off-shell gluon) transitions, which are of order $\alpha_s^2$. Their impacts on the CP-averaged branching ratios and CP-violating asymmetries are examined. We find that these higher order penguin contraction contributions have significant impacts on some specific decay modes. Since $B\to \pi K^{\ast}$, $K \rho$ decays involve the same electro-weak physics as $B\to \pi K$ puzzles, we present a detailed analysis of these decays and find that the five R-ratios for $B\to \pi K^{\ast}$, $K \rho$ system are in agreement with experimental data except for $R(\pi K^*)$. Generally, these new contributions are found to be important for penguin-dominated $B\to PV$ decays.Comment: 45 pages, 12 figures. Theoretical uncertainties considered. Gauge invariance proved. Version to appear in PR

A Top-down Model for Cash CLO

We propose a top-down model for cash CLO. This model can consistently price cash CLO tranches both within the same deal and across different deals. Meaningful risk measures for cash CLO tranches can also be defined and computed. This method is self-consistent, easy to implement and computationally efficient. It has the potential to bring the much needed pricing transparency to the cash CLO markets; and it could also greatly improve the risk management of cash instruments.Comment: 14 pages, 12 figure

Estimation of Extreme Quantiles for Functions of Dependent Random Variables

We propose a new method for estimating the extreme quantiles for a function of several dependent random variables. In contrast to the conventional approach based on extreme value theory, we do not impose the condition that the tail of the underlying distribution admits an approximate parametric form, and, furthermore, our estimation makes use of the full observed data. The proposed method is semiparametric as no parametric forms are assumed on all the marginal distributions. But we select appropriate bivariate copulas to model the joint dependence structure by taking the advantage of the recent development in constructing large dimensional vine copulas. Consequently a sample quantile resulted from a large bootstrap sample drawn from the fitted joint distribution is taken as the estimator for the extreme quantile. This estimator is proved to be consistent. The reliable and robust performance of the proposed method is further illustrated by simulation.Comment: 18 pages, 2 figure

Compacting solid waste materials generated in Missouri to form new products: final technical report

Presented at the 32nd Annual Conference of Missouri Waste ControlThe unique high-pressure compaction technology developed at Capsule Pipeline Research Center (CPRC) of University of Missouri-Columbia was used to study the compaction of combustible components of municipal solid waste and flyash generated from coal-fired power plants. By compaction, the combustible wastes can be turned into uniform, densified solids for use as fuel; the flyash can be turned into high-valued building elements such as bricks and blocks.This research project was sponsored by the Solid Waste Management Program, Missouri Department of Natural Resources (MDNR) for the period from January 1, 2001 to December 29, 2001. (MDNR Award Project no. 00038-1