Reseña: On the formalization of continuous-time Markov chains in HOL

Se ha publicado un trabajo de razonamiento formalizado en HOL4 titulado On the formalization of continuous-time Markov chains in HOL.

Sus autores son Liya Liu, Osman Hasan y Sofiène Tahar (de la Concordia University, Montreal, Canadá).

Su resumen es

Continuous-time Markov chain has been extensively applied to model diverse real-world systems. The analysis of these systems has been conducted using conventional simulation technique and computer algebra systems, more recently, probabilistic model checking. However, these methods either cannot guarantee accurate analysis or are not scalable due to the unacceptable computation consumption. As a complemental technique, theorem proving is proposed to reason about continuous-time Markov chain using HOL theorem proving. To our best knowledge, the formalization of continuous-time Markov chain has not been found in any theorem prover. In this report, we provide the idea on the formal definition of continuous-time Markov chain and two of its formally verified properties as the first step to formalize the continuous-time Markov chain theory. Also, we present the next step and the predict the potential challenges in the formalization process. Finally, a certain of applications are listed to be targeted using the formalized continuous-time Markov chain.

RA2012: Verificación en Isabelle de propiedades de funciones sobre listas (1)

En la clase de hoy del curso de Razonamiento automático se han comentado las soluciones de los ejercicios de verificación en Isabelle de propiedades de funciones sobre listas de las siguientes relaciones:

Reseña: A certified reduction strategy for homological image processing

Se ha publicado un trabajo de verificación formal con Coq titulado A certified reduction strategy for homological image processing.

Sus autores son María Poza, César Domínguez, Jónathan Heras y Julio Rubio (de la Universidad de la Rioja).

Su resumen es

The analysis of digital images using homological procedures is an outstanding topic in the area of Computational Algebraic Topology. In this paper, we describe a certified reduction strategy to deal with digital images, but preserving their homological properties. We stress both the advantages of our approach (mainly, the formalisation of the mathematics allowing us to verify the correctness of algorithms) and some limitations (related to the performance of the running systems inside proof assistants). The drawbacks are overcome using techniques that provide an integration of computation and deduction. Our driving application is a problem in bioinformatics, where the accuracy and reliability of computations are specially requested.

El código de las teoría Coq correspondientes al trabajo se encuentra aquí.

LMF2013: Algoritmo DPLL (Davis, Putnam, Logemann y Loveland)

En la segunda parte de la clase de hoy del curso de Lógica matemática y fundamentos (de 3º de Grado en Matemáticas) hemos estudiado el algoritmo DPLL (Davis, Putnam, Logemann y Loveland).

Además, se ha comentado la propuesta del 4º ejercicio evaluable consistente en la implementación en Haskell del algoritmo de DPLL y de refinamientos de resolución.

Las transparencias utilizadas son las del tema 6
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