Logic Programming and the INTERNET

Editorial for Theory and Practice of Logic Programming's special issue on 'Logic Programming and the INTERNET'

Aplicación de la Descomposición Empírica en Modo a la Predicción del Mercado Bursátil con los Modelos de ARIMA-ARCH y Redes Neuronales Artificiales Evolutivas

Tesis de Maestría donde se propone un modelo de Ensembles de Redes Neuronales Artificiales para predecir series de tiempo financiaeras de MéxicoEl mercado bursátil es un sistema dinámico que se caracteriza por su complejidad, volatilidad, no estacionariedad, irregularidad, pero sobre todo por las repentinas y pronunciadas caídas en los precios. Dadas estas características, y con el fin de contrarrestar las fluctuaciones aparentemente aleatorias, la inherente no linealidad en los datos financieros, y puesto que en muchos de los enfoques tradicionales que abordan la predicción del mercado bursátil en periodos de crisis, estos por lo regular no son capaces de capturar de manera fiable los rasgos distintivos del fenómeno. En esta investigación, se propone como primer paso, descomponer a los indicadores que representan al mercado accionario de los Estados Unidos y México en periodos de crisis, mediante la herramienta llamada Descomposición Empírica en Modos (DEM) que se encarga de descomponer la serie original de los índices accionarios en un número finito de descomposiciones llamadas Funciones de Modo Intrínseco (FMIs) y un elemento residual. A continuación, cada una de las FMIs y el residuo, son pronosticadas individualmente, utilizando por un lado, un modelo paramétrico (Autorregresivo Integrado de Media Móvil-Modelo de Volatilidad Condicional Heterocedástico (ARIMA-ARCH)) y por otro lado, por un modelo no paramétrico Redes Neuronales Artificiales (RNAs), este último es configurado por medio de un algoritmo evolutivo llamado Selección de Características de Programación Evolutiva de Redes Neuronales Artificiales (FS- EPNet). Posteriormente, se adquiere la predicción del modelo paramétrico, mediante la suma de las predicciones resultantes de cada FMI y del residuo, de igual forma se realiza el mismo procedimiento para obtener la predicción final del modelo no paramétrico. Finalmente, las predicciones de los modelos paramétrico y no paramétrico son combinadas mediante un promedio ponderado, para producir una combinación de pronósticos, estas predicciones a su vez son comparadas. Los resultados empíricos obtenidos demuestran que los modelos que colaboraron en conjunción con la técnica de descomposición de señales DEM, tienen una predicción más precisa de la crisis bursátil, a diferencia de los modelos que confeccionaron su pronóstico de manera aislada.COMECyT, CONACy

Functionally Graded Media

The notions of uniformity and homogeneity of elastic materials are reviewed in terms of Lie groupoids and frame bundles. This framework is also extended to consider the case Functionally Graded Media, which allows us to obtain some homogeneity conditions.Comment: 20 pages, 5 figure

Some applications of semi-discrete variational integrators to classical field theories

We develop a semi-discrete version of discrete variational mechanics with applications to numerical integration of classical field theories. The geometric preservation properties are studied.Comment: 14 page

The Polish Guarantee Scheme (Poland GFC)

Faced with the global financial crisis of 2007–2009, Poland implemented a scheme of State support for financial institutions. In view of a potential global credit crunch, it aimed at improving short- and medium-term liquidity of domestic financial institutions. The scheme came into force on March 13, 2009, and was approved by the European Commission under European Union State Aid rules on September 25, 2009. The scheme enabled the Ministry of Finance, on behalf of the State Treasury, to provide support in the form of Treasury guarantees on newly issued bank debt and the exchange of Treasury bonds for less liquid assets. This case exclusively examines Treasury guarantees on debt securities. Initially, only domestic banks, including subsidiaries of foreign financial institutions, could apply for guarantees. In 2011, eligibility was expanded to include cooperative savings and credit institutions and the National Cooperative Savings and Credit Institution. An initial overall cap was set at PLN 40 billion ($13.7 billion) before being raised to PLN 160 billion in 2012. The European Commission approved 19 prolongations of the scheme—the last in December 2018. No institutions applied for coverage and the issuance window expired on May 31, 2019

Term Securities Lending Facility (TSLF) (U.S. GFC)

The 2007–09 financial crisis reached a critical stage in March 2008. Amid falling house prices and downgrades of mortgage-related securities, financial markets became severely disrupted. The Federal Reserve—the US central bank—became increasingly concerned about the inability of the 20 primary dealers, including the five largest US investment banks, to fund themselves in short-term funding markets, such as the repurchase agreement market, then estimated at $10 trillion. In response, the Fed created several emergency lending facilities to restore market liquidity that required the Fed to invoke Section 13(3) of the Federal Reserve Act. The Term Securities Lending Facility authorized the Federal Reserve Bank of New York to lend to primary dealers up to$200 billion of highly liquid US Treasuries against collateral that was particularly illiquid at the time. Eligible collateral initially included triple-A private-label mortgage-backed securities but was later broadened. In July 2008, an additional $50 billion was allocated for a TSLF Options Program. The TSLF operated between March 27, 2008, and February 1, 2010. Usage peaked at$236 billion in October 2008. Overall, 18 of the 20 primary dealers participated and the Fed collected $781 million in fees

Extended Hamiltonian systems in multisymplectic field theories

We consider Hamiltonian systems in first-order multisymplectic field theories. We review the properties of Hamiltonian systems in the so-called restricted multimomentum bundle, including the variational principle which leads to the Hamiltonian field equations. In an analogous way to how these systems are defined in the so-called extended (symplectic) formulation of non-autonomous mechanics, we introduce Hamiltonian systems in the extended multimomentum bundle. The geometric properties of these systems are studied, the Hamiltonian equations are analyzed using integrable multivector fields, the corresponding variational principle is also stated, and the relation between the extended and the restricted Hamiltonian systems is established. All these properties are also adapted to certain kinds of submanifolds of the multimomentum bundles in order to cover the case of almost-regular field theories.Comment: 36 pp. The introduction and the abstract have been rewritten. New references are added and some little mistakes are corrected. The title has been slightly modifie