74,406 research outputs found
Renormalization of Fermion-Flavour Mixing
We report on an explicit on-shell framework to renormalize the
fermion-flavour mixing matrices in the Standard Model and its extensions, at
one-loop level. It is based on a novel procedure to separate the external-leg
mixing corrections into gauge-independent self-mass and gauge-dependent
wave-function renormalization contributions.Comment: to appear in Proceedings of Lepton-Photon 2009, Hamburg, German
Theory of Change As A Tool For Strategic Planning
The purpose of this paper is to introduce the use of the Theory of Change approach for planning community-based initiatives. Through lessons learned from a case study of how TOC was applied during the planning phase of The Wallace Foundation Parents and Communities for Kids (PACK) initiative, the utility of this technique and the challenges involved in employing it are illustrated. The case study was designed to highlight lessons that will be of most interest to program planners, evaluators, and funders who are interested in applying this method to their work
The Gardner Category and Non-local Conservation Laws for N=1 Super KdV
The non-local conserved quantities of N=1 Super KdV are obtained using a
complete algebraic framework where the Gardner category is introduced. A
fermionic substitution semigroup and the resulting Gardner category are defined
and several propositions concerning their algebraic structure are proven. This
algebraic framework allows to define general transformations between different
nonlinear SUSY differential equations. We then introduce a SUSY ring extension
to deal with the non-local conserved quantities of SKdV. The algebraic version
of the non-local conserved quantities is solved in terms of the exponential
function applied to the of the local conserved quantities of SKdV.
Finally the same formulas are shown to work for rapidly decreasing superfields.Comment: 17 page
Scenario Modeling for the Management of International Bond Portfolios
We address the problem of portfolio management in the international bond markets. Interest rate risk in the local market, exchange rate volatility across markets, and decisions for hedging currency risk are integral parts of this problem. The paper develops a stochastic programming optimization model for integrating these decisions in a common framework. Monte Carlo simulation procedures, calibrated using historical observations of volatility and correlation data, generate jointly scenarios of interest and exchange rates. The decision maker's risk tolerance is incorporated through a utility function, and additional views on market outlook can also be incorporated in the form of user specified scenarios. The model prescribes optimal asset allocation among the different markets and determines bond-picking decisions and appropriate hedging ratios. Therefore several interrelated decisions are cast in a common framework, while in the past these issues were addressed separately. Empirical results illustrate the efficacy of the simulation models in capturing the uncertainties of the Salomon Brothers international bond market index.
Singular hermitian metrics on vector bundles
We introduce a notion of singular hermitian metrics (s.h.m.) for holomorphic
vector bundles and define positivity in view of -estimates. Associated
with a suitably positive s.h.m. there is a (coherent) sheaf 0-th kernel of a
certain -complex. We prove a vanishing theorem for the cohomology of this
sheaf. All this generalizes to the case of higher rank known results of Nadel
for the case of line bundles. We introduce a new semi-positivity notion,
-nefness, for vector bundles, establish some of its basic properties and
prove that on curves it coincides with ordinary nefness. We particularize the
results on s.h.m. to the case of vector bundles of the form ,
where is a -nef vector bundle and is a positive (in the sense of
currents) line bundle. As applications we generalize to the higher rank case 1)
Kawamata-Viehweg Vanishing Theorem, 2) the effective results concerning the
global generation of jets for the adjoint to powers of ample line bundles, and
3) Matsusaka Big Theorem made effective.Comment: LaTex (article) 25 pages; revised: minor changes; to appear in
Crelle's J; dedicated to Michael Schneide
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