Anacyclus × malvesiensis (Asteraceae), un híbrido nuevo para la flora valenciana

Se comunica el hallazgo de un nuevo híbrido del género Anacyclus L. (Asteraceae) localizado en el término municipal de Llombai (Valencia) que denominamos Anacyclus × malvesiensis, y cuyos parentales son A. clavatus y A. valentinusA new hybrid of genus Anacyclus L. (Asteraceae) is described and illustrated from Valencia (Spain): Anacyclus × malvesiensis (Anacyclus clavatus × Anacyclus valentinus)

Sistemas de ciudades y tamaño: Un modelo de equilibrio general

El objetivo de este artículo es analizar la importancia de las economías de aglomeración en la determinación del tamaño y la dimensión óptima de un sistema de ciudades. A partir de un modelo bisectorial de competencia perfecta explicamos la formación y el crecimiento de las ciudades. Ello, nos obliga a suponer que en cada aglomeración urbana existen dos sectores (economías domésticas y producción), la familias poseen un nivel de utilidad exógeno y las funciones de producción se caracterizan por depender de un solo input trabajo, presentan rendimientos constantes a escala y poseen un factor de progreso técnico neutral de Hicks. La primera gran conclusión que se extrae de este estudio es que en la primera fase de desarrollo de las ciudades, cuando existen economías de aglomeración, aquella que está especializada en la producción de un determinado bien es a también la más dimensionada y emplea a más trabajadores que la ciudad diversificada; sin embargo, en la medida que aparecen las deseconomías de aglomeración, ésta última registra un incremento poblacional y emplea más fuerza laboral. Otras conclusiones relevantes que se extraen de este trabajo son: (1) la producción óptima coincide con la de equilibrio, y (2) cuando una ciudad alcanza su dimensión óptima, el diferencial de renta del suelo es mayor o igual que el coste fijo de producción

La política de dividendos de las empresas cotizadas españolas: Tendencias recientes

En el presente trabajo analizamos, para el caso español, una tendencia que se está produciendo en múltiples países como es la reducción del número de empresas que distribuyen dividendos. Esta reducción en el número de pagadoras va acompañada por la concentración de dividendos en un grupo reducido de empresas. Para ello analizamos la evolución de los dividendos en el mercado español entre 2009 y 2017. En el trabajo también identificamos las diferentes características de las empresas pagadoras y no pagadoras de dividendos. Para concluir, constatamos la concentración de los dividendos en España en torno a las empresas más grandes y estables. Por último, haré un breve repaso sobre las alternativas al pago de dividendos.In this paper we analyze, for the Spanish case, a trend that is occurring in multiple countries such as the reduction in the number of companies that distribute dividends. This reduction in the number of payers is accompanied by the concentration of dividends in a small group of companies. For this, we analyze the evolution of dividends in the Spanish market between 2009 and 2017. At work we also identify the different characteristics of the paying and non-paying companies. To conclude, we see the concentration of dividends in Spain around the largest and most stable companies. Finally, I will briefly review the alternatives to paying dividends.Departamento de Economía Financiera y ContabilidadMáster en Administración de Empresa

A RBES for Generating Automatically Personalized Menus

Food bought at supermarkets in, for instance, North America or the European Union, give comprehensive information about ingredients and allergens. Meanwhile, the menus of restaurants are usually incomplete and cannot be normally completed by the waiter. This is specially important when traveling to countries with a di erent culture. A curious example is "calamares en su tinta" (squid in its own ink), a common dish in Spain. Its brief description would be "squid with boiled rice in its own (black) ink", but an ingredient of its sauce is flour, a fact very important for celiacs. There are constraints based on religious believes, due to food allergies or to illnesses, while others just derive from personal preferences. Another complicated situation arise in hospitals, where the doctors' nutritional recommendations have to be added to the patient's usual constraints. We have therefore designed and developed a Rule Based Expert System (RBES) that can address these problems. The rules derive directly from the recipes of the di fferent dishes and contain the information about the required ingredients and ways of cooking. In fact, we distinguish: ingredients and ways of cooking, intermediate products (like sauces, that aren't always made explicit) and final products (the dishes listed in the menu of the restaurant). For a certain restaurant, customer and instant, the input to the RBES are: actualized stock of ingredients and personal characteristics of that customer. The RBES then prepares a "personalized menu" using set operations and knowledge extraction (thanks to an algebraic inference engine [1]). The RBES has been implemented in the computer algebra system MapleTM2015. A rst version of this work was presented at "Applications of Computer Algebra 2015" (ACA'2015) conference. The corresponding abstract is available at [2].Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

A fast functional approach to personalized menus generation using set operations

The authors developed some time ago a RBES devoted to preparing personalized menus at restaurants according to the allergies, religious constraints, likes and other diet requirements as well as products availability. A first version was presented at the "Applications of Computer Algebra 2015" (ACA'2015) conference and an improved version to the "5th European Seminar on Computing" (ESCO2016). Preparing personalized menus can be specially important when traveling abroad and facing unknown dishes in a menu. Some restaurants include icons in their menu regarding their adequateness for celiacs or vegetarians and vegans, but this is not always a complete information, as it doesn't consider, for instance, personal dislikes or uncommon allergies. The tool previously developed can obtain, using logic deduction, a personalized menu for each customer, according to the precise recipes of the restaurant and taking into account the data given by the customer and the ingredients out of stock (if any). Now a new approach has been followed, using functions and set operations and the speed has been increased by three orders of magnitude, allowing to deal with huge menus instantly. Both approaches have been implemented on the computer algebra system Maple and are exemplified using the same recipes in order to compare their performances.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Computer Algebra-based RBES personalized menu generator

People have many constraints concerning the food they eat. These constraints can be based on religious believes, be due to food allergies or to illnesses, or can be derived just from personal preferences. Therefore, preparing menus at hospitals and restaurants can be really complex. Another special situation arise when travel- ing abroad. It is not always enough to know the brief description in the restaurant menu or the explanation of the waiter. For example, “calamares en su tinta” (squid in its own ink) is a delicious typical Spanish dish, not well-known abroad. Its brief description would be “squid with boiled rice in its own (black) ink”. But an in- gredient (included in a small amount, in order to thicken the sauce) is flour, a fact very important for someone suffering from celiac disease. Therefore, we have con- sidered that it would be very interesting to develop a Rule Based Expert System (RBES) to address these problems. The rules derive directly from the recipes and contain the information about required ingredients and names of the dishes. We distinguish: ingredients and ways of cooking, intermediate products (like “mayon- naise”, that doesn’t always appear explicitly in the restaurants’ menus) and final products (like “seafood cocktail”, that are the dishes listed in the restaurant menu). For each customer at a certain moment, the input to the system are: on one hand, the stock of ingredients at that moment, and on the other, the religion, allergies and restrictions due to illnesses or personal preferences of the customer. The RBES then constructs a “personalized restaurant menu” using set operations and knowl- edge extraction (thanks to an algebraic Groebner bases-based inference engine[1]). The RBES has been implemented in the computer algebra system Maple TM 18(us-ing its convenient Embedded Components) and can be run from computers and tablets using Maple TM or the Maple TM PlayerUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

EL VOTO ECONÓMICO EN DEMOCRACIA. EL CASO DE ESPAÑA

El análisis del voto económico en los regímenes democráticos es un programa de investigación de extraordinaria relevancia y vigencia científica. Nuestro objetivo es analizar como influyen los factores socioeconómicos y los condicionantes racionales de carácter económico, en la decisión final de los electores. Para ello, planteamos un modelo comprehensivo, en el que se incluyen un conjunto de variables explicativas que sintetizan los planteamientos más relevantes del comportamiento electoral: identificación partidista, teoría de la decisión racional y base socioestructural del voto. Incluso, defendemos la idea de que esta propuesta habría de convertirse en un desideratum. De todo lo anterior, no debemos inferir, que estamos ante un trabajo teórico, pues nuestro objetivo último es identificar los factores que determinan la decisión final de los electores españoles; y a partir de ahí, analizar la influencia de las variables de índole económico, en la orientación de su voto. A la luz de las estimaciones realizadas, podemos afirmar, que en España se ha utilizado el voto económico, como premio-castigo: perjudicó al PSOE en los comicios legislativos de 1993 y favoreció las expectativas electorales del PP en esta convocatoria. Por otra parte, el desempleo y la renta, como factores socioestructurales que condicionan la situación personal de los votantes, han desempeñado un papel relevante en la decisión final de los electores españoles. No podemos finalizar este resumen, sin resaltar, que en esta cuestión España no es muy diferente a otros países industrializados. Classification-JEL :Economía, voto, electorado, votantes españoles, desempleo y renta.

Numerical approximation of solution derivatives of singularly peprturbed parabolic problems of convection-difffusion type

Numerical approximations to the solution of a linear singularly perturbed parabolic convection-diffusion problem are generated using a backward Euler method in time and an upwinded finite difference operator in space on a piecewise-uniform Shishkin mesh. A proof is given to show first order convergence of these numerical approximations in an appropriately weighted C^1$-norm. Numerical results are given to illustrate the theoretical error bounds

Singularly perturbed initial-boundary value problem with a pulse in the initial condition

A singularly perturbed parabolic equation of reaction-diffusion type is examined. Initially the solution approximates a concentrated source, which causes an interior layer to form within the solution for all future times. Combining a classical finite difference operator with a layer-adapted mesh, parameter-uniform convergence is established. Numerical results are presented to illustrate the theoretical error bounds