Improved Quantum Hard-Sphere Ground-State Equations of State

The London ground-state energy formula as a function of number density for a system of identical boson hard spheres, corrected for the reduced mass of a pair of particles in a sphere-of-influence picture, and generalized to fermion hard-sphere systems with two and four intrinsic degrees of freedom, has a double-pole at the ultimate \textit{regular} (or periodic, e.g., face-centered-cubic) close-packing density usually associated with a crystalline branch. Improved fluid branches are contructed based upon exact, field-theoretic perturbation-theory low-density expansions for many-boson and many-fermion systems, appropriately extrapolated to intermediate densities, but whose ultimate density is irregular or \textit{random} closest close-packing as suggested in studies of a classical system of hard spheres. Results show substantially improved agreement with the best available Green-function Monte Carlo and diffusion Monte Carlo simulations for bosons, as well as with ladder, variational Fermi hypernetted chain, and so-called L-expansion data for two-component fermions.Comment: 15 pages and 7 figure

An Agent-Based Approach for Data Fusion in Homeland Security

This article presents an agent-based solution for data fusion in Homeland Security. Communication technology has been developed very fast in the last decades. We can get lots of data in milliseconds. Our current problem is to process such amounts of data in order to provide useful information. We have to focus our effort on developing intelligent information systems able to handle big amounts of data extracting or revealing relations among data and able to produce information easily understandable for the human user. That is the case of data fusion in tactical operations, especially in the field of defense and Homeland security. Our research is focused on obtaining a Multi-agent system able to inference future enemy’s actions or behaviors from data received from heterogeneous sensors

Bending behavior analysis of geogrid reinforced adobe walls

La tierra cruda constituye el material de construcción más importante en muchas regiones del planeta. Dado el riesgo sísmico existente en la mayor parte de estas regiones, es necesario el desarrollo de técnicas de refuerzo eficaces y adecuadas desde un punto de vista tecnológico y socioeconómico. Este artículo analiza desde un punto experimental y analítico el comportamiento a flexión de muros de adobe reforzados con geomallas. Las leyes momento-curvatura de los muros ensayados son aproximadas mediante una serie de modelos analíticos que permiten analizar el comportamiento del material compuesto adobe-geomalla. Los resultados obtenidos muestran como la geomalla mejora el comportamiento de la mampostería de adobe en términos de resistencia y ductilidad, mejorando así su comportamiento en caso de movimiento sísmico.Rammed earth is a widely used building material in many regions of the world. Due to the high seismic risk in those areas, earthen constructions require suitable and efficient reinforcement techniques from a technological and socioeconomic point of view. This paper analyzes the bending behavior of geogrid reinforced adobe walls from an experimental and analytical point of view. The experimental bending moment-curvature relationships are analytically approached. The results show how geogrid reinforcement improves the performance of adobe masonry in terms of strength and ductility. Thus, a better seismic performance is achieve

Bending behavior analysis of geogrid reinforced adobe walls

La tierra cruda constituye el material de construcción más importante en muchas regiones del planeta. Dado el riesgo sísmico existente en la mayor parte de estas regiones, es necesario el desarrollo de técnicas de refuerzo eficaces y adecuadas desde un punto de vista tecnológico y socioeconómico. Este artículo analiza desde un punto experimental y analítico el comportamiento a flexión de muros de adobe reforzados con geomallas. Las leyes momento-curvatura de los muros ensayados son aproximadas mediante una serie de modelos analíticos que permiten analizar el comportamiento del material compuesto adobe-geomalla. Los resultados obtenidos muestran como la geomalla mejora el comportamiento de la mampostería de adobe en términos de resistencia y ductilidad, mejorando así su comportamiento en caso de movimiento sísmico.Rammed earth is a widely used building material in many regions of the world. Due to the high seismic risk in those areas, earthen constructions require suitable and efficient reinforcement techniques from a technological and socioeconomic point of view. This paper analyzes the bending behavior of geogrid reinforced adobe walls from an experimental and analytical point of view. The experimental bending moment-curvature relationships are analytically approached. The results show how geogrid reinforcement improves the performance of adobe masonry in terms of strength and ductility. Thus, a better seismic performance is achieve

ANÁLISIS BROMATOLÓGICO DE FRUTOS DE CHILE “SIETE CALDOS” (Capsicum annuum) CULTIVADOS EN CONDICIONES DE CIELO ABIERTO Y CASA SOMBRA

The accessions from a germplasm bank of “siete caldos” peppers (Capsicum annuum) from the Escuela de Estudios Agropecuarios de Mezcalapa, Chiapas, México, were evaluated, grown under shade house and outdoor conditions. The fruits harvested from different tonalities were analyzed with food science techniques. The results showed that 86 % of the moisture content of green fruits harvested outdoor do not present significant statistical differences against shade house pepper fruits. Of the protein content, 21 % is the highest value reported for purple color fruits under the two cultivation conditions, and the red fruits presented values of 8.00% and 7.34%, for outdoor and shade house, respectively. The fruits in tonalities of red-green and red-dark-green color showed the highest values of raw fiber (16.10% y 16.50%, respectively) outdoor and ash (9.0%).Se evaluaron accesiones de un banco de germoplasma de chiles “siete caldos” (Capsicum annuum) de la Escuela de Estudios Agropecuarios de Mezcalapa, Chiapas, México; cultivados bajo condiciones de casa sombra y cielo abierto. Los frutos cosechados de diferentes tonalidades fueron analizados bromatológicamente. Los resultados mostraron que 86% del contenido de humedad de frutos verdes cosechados en cielo abierto no presentan diferencias estadísticas significativas contra frutos de chiles de casa sombra. El 21% del contenido de proteínas, es el valor más alto reportado para frutos de color morado bajo las dos condiciones de cultivo, y los frutos rojos presentaron valores de 8.00% y 7.34%, para cielo abierto y casa sombra respectivamente. Los frutos en tonalidades de color rojo-verde y rojo-oscuro-verde registraron los valores más altos de fibra cruda (16.10% y 16.50%, respectivamente) a cielo abierto y ceniza (9.0%)

Experimental and Analytical Approach for the Assesment of Flexural Strength of Adobe Masonry

This paper presents an investigation about the flexural behavior of adobe masonry. It is focused on the development of constitutive models that can serve as a basis for the establishment of new design guidelines for adobe constructions, with special emphasis on seismic reinforcements. The paper analyzes the flexural behaviour of geogrid reinforced adobe walls. The experimental seismic tests of geogrid reinforced adobe houses have proven the effectiveness of the reinforcement technique. However, additional research is needed to develop constitutive models that can be used to quantify the actual performances of the reinforced adobe. For this purpose, bending tests have been carried out to obtain experimental curvature-moment relationships for reinforced and non reinforced adobe walls. Analytical models have been developed to approach these experimental laws, using equilibrium and compatibility equations similar to those usually applied for the flexural behaviour of reinforced concrete. The constitutive models of the individual materials are previously obtained through experimental tests, and simplified constitutive models are proposed for the governing equations. The analytical models show the ductility of adobe masonry, and how ductility increases when adobe is reinforced with geogrids. The proposed mathematical models and methodology can be applied to other structural elements and reinforcement systems. They can serve as a basis for the development of new design guidelines for adobe masonry

Dielectric and dynamic mechanical study of the mobility of poly(t-butylacrylate) chains in diblock copolymers: polystyrene-b-poly(t-butylacrylate)

A calorimetric, dielectric and dynamic-mechanical study of the dynamics of the poly(t-butyl acrylate) (PtBa) chains has been carried out in a PtBa homopolymer and two polystyrene (PS)-b-PtBa block copolymers with different PtBa chain lengths. The DSC results show that the size of the cooperative rearranging regions is similar in the homopolymers and the copolymers, both for the PtBa rich- and the PS-rich regions. Therefore, no significant contributions are found arising from composition fluctuations in the copolymers. The relaxation map obtained from dielectric relaxation indicates that there are no differences in the temperature dependence of the α-relaxation of the PtBa block in the three samples studied. However, there are larger differences for the values obtained from DMTA experiments. Contrary to the α-relaxation, the relaxation map for the β-transition shows that the characteristic times for the PtBa blocks are smaller in the homopolymer than in the copolymers. In principle, these are unexpected results because the β-relaxations have a more local character than the α-ones. The width of the α-relaxation increases with T for all the samples, and it is slightly larger for the copolymers. The intensity of the α-relaxation is larger (between 3 and 4 times) for the homopolymer. Considering the molecular weights of the PtBa blocks, this effect has to be ascribed to the existence of frozen amorphous PtBa due to the existence of the glassy PS domains in the microphase separated copolymers. Molecular Dynamic Simulations (MDSs) for different sequences of the polymers under study were carried out. The conformational analysis was carried out between 1000 and 1700 K. The analysis of the variation of angles 1 and 2 of the ester group of PtBa points out the existence of a correlation between the conformational changes of the side group of the polymer chains and their relaxational behaviour