Search-theoretic models of international currency

Money ; International finance

Operaciones mentales y su relación con el rendimiento académico en Matemáticas en estudiantes de octavo año, del Liceo de Miramar

Trabajo final de graduación compuesto de 120 páginas en formato PDF.Se tiene, entonces, que la enseñanza de las Matemáticas conjuga tres elementos que se deben tomar en cuenta: los procedimientos, los conceptos y el simbolismo. Por lo tanto, esta investigación se avoca a escudriñar acerca de procedimientos utilizados por los docentes de Matemática para impartir sus lecciones, la metodología que utilizan los muchachos para aprender, pero, primordialmente, el reconocimiento y relación que existe entre el nivel de las operaciones mentales de los estudiantes y el desempeño escolar en Matemática.Universidad Estatal a Distancia de Costa Ric

Vapor-liquid equilibrium and equation of state of two-dimensional fluids from a discrete perturbation theory

The interest in the description of the properties of fluids of restricted dimensionality is growing for theoretical and practical reasons. In this work, we have firstly developed an analytical expression for the Helmholtz free energy of the two-dimensional square-well fluid in the Barker--Henderson framework. This equation of state is based on an approximate analytical radial distribution function for $d$-dimensional hard-sphere fluids ($1\leq d\leq 3$) and is validated against existing and new simulation results. The so-obtained equation of state is implemented in a discrete perturbation theory able to account for general potential shapes. The prototypical Lennard-Jones and Yukawa fluids are tested in its two-dimensional version against available and new simulation data with semi-quantitative agreement.Comment: 9 pages, 6 figures; v2: new references adde

Posacuerdo en el caribe colombiano. Ilegalidad y nuevas violencias

The present paper aims to demostrate that the outcome of the peace negotiations that advanced in Havana, between the Colombian government and the Revolutionary Armed Forces of Colombia People's Army (FARC-EP), does not significantly alter the security situation Present in the Colombian Caribbean. This is because the armed insurgency represented by the Bloque Caribe or Martín Caballero of the FARC EP and the Northern War Front of the National Liberation Army (ELN) was strategically defeated in this region of Colombia between 2004 and 2009. Giving way to new forms of criminal violence.  El presente trabajo se propone demostrar que el resultado de las negociaciones de paz que se adelantaron en la Habana, entre el gobierno colombiano y las Fuerzas Armadas Revolucionarias de Colombia Ejército del Pueblo (FARC-EP), no altera de manera significativa la situación de seguridad presente en la actualidad en el Caribe colombiano. Esto, porque la insurgencia armada representada por el Bloque Caribe o Martín Caballero de las FARC EP y el Frente de Guerra Norte del Ejército de Liberación Nacional (ELN), fue derrotada estratégicamente en esta región de Colombia, entre los años 2004 y 2009. Dando paso a nuevas formas de violencia criminal

Self-diffusion coefficient of the square-well fluid from molecular dynamics within the constant force approach

We present a systematic study of the self-diffusion coefficient for a fluid of particles interacting via the square-well pair potential by means of molecular dynamics simulations in the canonical (N,V,T) ensemble. The discrete nature of the interaction potential is modeled through the constant force approximation and the self-diffusion coefficients is determined for several packing fractions at super critical thermodynamic states. The dependence of the self-diffusion coefficient with the potential range $\lambda$ is analyzed in the range of $1.1 \leq \lambda \leq 1.5$. The obtained molecular dynamics simulations results are in agreement with the self-diffusion coefficient predicted with the Enskog method. Additionally, we soh that the diffusion coefficient is very sensitive to the potential range, $\lambda$, at low densities leading to a density dependence of this coefficient not shared with other macroscopic properties such as the equation of state. The constant force approximation used in this work to model the discrete pair potential has shown to be an excellent scheme to compute the transport properties using standar computer simulations. Finally, the simulation results presented here are resourceful to improving theoretical approaches, such as the Enskog method

Diseño e implementación de un regulador solar de potencia de bajo peso para controlar la carga de la batería de un vehículo solar : Aplicación a las baterías de li-po en el vehículo solar del semillero de investigación en energías renovables

Este proyecto busca diseñar e implementar un sistema de control capaz de medir señales eléctricas de un panel solar y de una batería de iones de litio en un vehículo solar, con el fin de aumentar la vida útil de dicha batería y de generar autonomía en cuanto a la recarga desde el panel, sin necesidad de estar conectándose manualmente. Debido a que actualmente no se cuenta con un sistema de controlador que cumpla con esta función, se opta por implementar dicho sistema para que el vehículo tenga mayor autonomía en cuanto a los ciclos de carga y descarga de la batería. Para ello, este trabajo tendrá un enfoque en investigación aplicada con diseño experimental, es decir, se tendrán en cuenta conceptos de investigaciones y resultados anteriores para dicha implementación; la cual se hará con el estudio de varios sistemas digitales para seleccionar el que mejor se adapte, con el Arduino UNO como la opción más tentativa para la implementación de este proyecto. Se usará el entorno de desarrollo EAGLE® para crear la placa de circuito y se construirá una caja protectora adaptada al vehículo solar

Accounting for Changing Inequality in Costa Rica, 1980-1999

After declining from the mid-1970s to the mid-1980s, earnings inequality in Costa Rica stabilized from 1987 to 1992 and then increased from 1992 to 1999. In this paper we use recently-developed techniques to measure the extent to which these changes in earnings inequality were the result of changes associated with the distributions (or .quantities.) of personal and work place characteristics of workers, and the earnings differences (or .prices.) associated with those characteristics. We present evidence that the most important cause of the fall in inequality prior to 1987 was a decline in returns to education, which in turn was caused by an increase in the supply of more-educated workers. We find that the most important causes of rising inequality in the 1990s were the end of this decline in returns to education and increases in the variance of hours worked among workers. Inequality in hours worked increased because of an increase in the proportion of workers working a non-standard work week (part-time or over-time)inequality, Latin America, labor

Gains from trade and measured total factor productivity

We develop and calibrate a model where di¤erences in factor en-dowments lead countries to trade di¤erent goods, so that the existenceof international trade changes the sectorial composition of output fromone country to another. Gains from trade re ect in total factor produc-tivity. We perform a development decomposition, to assess the impactof trade and barriers to trade on measured TFP. In our sample, themedian size of that e¤ect is about 6.5% of output, with a median of17% and a maximum of 89%. Also, the model predicts that changes inthe terms of trade cause a change of productivity, and that e¤ect hasan average elasticity of 0.71.