On the Optimal Boundary of a Three-Dimensional Singular Stochastic Control Problem Arising in Irreversible Investment

de Angelis T, Federico S, Ferrari G. On the Optimal Boundary of a Three-Dimensional Singular Stochastic Control Problem Arising in Irreversible Investment. Center for Mathematical Economics Working Papers. Vol 509. Bielefeld: Center for Mathematical Economics; 2014.This paper examines a Markovian model for the optimal irreversible investment problem of a firm aiming at minimizing total expected costs of production. We model market uncertainty and the cost of investment per unit of production capacity as two independent one-dimensional regular diffusions, and we consider a general convex running cost function. The optimization problem is set as a three-dimensional degenerate singular stochastic control problem. We provide the optimal control as the solution of a Skorohod reflection problem at a suitable free-boundary surface. Such boundary arises from the analysis of a family of two-dimensional parameter-dependent optimal stopping problems and it is characterized in terms of the family of unique continuous solutions to parameter-dependent nonlinear integral equations of Fredholm type

Isotopic Grand Unification with the Inclusion of Gravity (revised version)

We introduce a dual lifting of unified gauge theories, the first characterized by the isotopies, which are axiom- preserving maps into broader structures with positive-definite generalized units used for the representation of matter under the isotopies of the Poincare' symmetry, and the second characterized by the isodualities, which are anti-isomorphic maps with negative-definite generalized units used for the representation of antimatter under the isodualities of the Poincare' symmetry. We then submit, apparently for the first time, a novel grand unification with the inclusion of gravity for matter embedded in the generalized positive-definite units of unified gauge theories while gravity for antimatter is embedded in the isodual isounit. We then show that the proposed grand unification provides realistic possibilities for a resolution of the axiomatic incompatibilities between gravitation and electroweak interactions due to curvature, antimatter and the fundamental space-time symmetries.Comment: 20 pages, Latex, revised in various details and with added reference

Families in Britain

9.95SIGLELD:82/25329(Families) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Family breakdown and reconstitution

SIGLELD:8318.172(SSRC-HR--6885). / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Changing practice: implementing validated paediatric pain assessment tools

This study attempted to address a lack of evidence-based pain management by implementing validated pain assessment tools across a children's hospital. The method used was action research. The first part of this study where nurses' views of pain tools was elicited has already been reported (Simons and Macdonald, 2004). An action research cycle of negotiation, assessment, diagnosing, planning, action, evaluation and withdrawal was utilized. Data collection occurred at two points in time. Three age-appropriate tools were implemented hospital-wide supported by education and clinical input. A survey of nurses was carried out six months and 12 months post implementation of the tools. At the same time evaluation of the use of the tool was performed. Six months after education and implementation 23 percent of children on 10 wards had a pain tool in use. This had increased to 40 percent six months later. There were many inconsistencies between the replies the nurses gave in relation to their reported use of the tools and the actual use of the tools