High-Temperature Polyimide Dielectric Materials for Energy Storage: Theory, Design, Preparation and Properties

The high operating temperature of dielectric capacitors applied in electric vehicles, aerospace and underground exploration require dielectric materials with high temperature resistance and high energy density. Polyimide (PI) turns out...

The W, Z scale functions kit for first passage problems of spectrally negative Lévy processes, and applications to control problems

In the last years there appeared a great variety of identities for first passage problems of spectrally negative Lévy processes, which can all be expressed in terms of two “q-harmonic functions” (or scale functions) W and Z. The reason behind that is that there are two ways of exiting an interval, and thus two fundamental “two-sided exit” problems from an interval (TSE). Since many other problems can be reduced to TSE, researchers developed in the last years a kit of formulas expressed in terms of the “W, Z alphabet”. It is important to note – as is currently being shown – that these identities apply equally to other spectrally negative Markov processes, where however the W, Z functions are typically much harder to compute. We collect below our favorite recipes from the “W, Z kit”, drawing from various applications in mathematical finance, risk, queueing, and inventory/storage theory. A small sample of applications concerning extensions of the classic de Finetti dividend problem is offered. An interesting use of the kit is for recognizing relationships between problems involving behaviors apparently unrelated at first sight (like reflection, absorption, etc.). Another is expressing results in a standardized form, improving thus the possibility to check when a formula is already known.

El proceso CIR en el mundo del modelaje en commodities: el modelo de forma reducida y de no arbitraje de dos factores de Ribeiro y Hodges (2004)

El presente artículo busca conmemorar el trabajo del profesor Stephen Ross mediante la exposición del modelo de Ribeiro y Hodges (2004), el cual incorpora por primera vez el proceso Cox-Ingersoll-Ross en el mundo del modelaje de commodities bajo la sombrilla de la llamada Storage Theory. Con base en lo anterior, se presenta primero el modelo en líneas generales, reseñando las razones que motivaron a su desarrollo y, acto seguido, se derivan de él las ecuaciones de pricing para cualquier contrato futuro que hace parte de una clase de contratos futuros sobre commodities. Por último, se esboza brevemente la forma en la que se calibra este modelo a través del filtro de Kalman y el método de Máxima Log-Verosimilitud, dado que sus variables de estado (el precio spot estándar y la tasa instantánea spot y bruta de conveniencia) no son observables, al mostrar la construcción de las ecuaciones de medida y de transición para el mismo bajo la óptica de Ribeiro y Hodges (2004b).

Optimal Scheme of Solving the Problem of Construction Enterprise Formwork Inventory with Storage Theory

The storage theory which plays a unique role in the application field of inventory management and spare parts adjustment has received extensive attention and application. However, the current researches on the application of the storage theory of intermittent return warehousing management are not sufficient enough. Under the support of the deterministic storage principle, this paper centers on the research of solving the problem of the optimal scheme of construction enterprise formwork inventory with the storage theory.