An Efficient Pipeline Wavefront Phase Recovery for the CAFADIS Camera for Extremely Large Telescopes

In this paper we show a fast, specialized hardware implementation of the wavefront phase recovery algorithm using the CAFADIS camera. The CAFADIS camera is a new plenoptic sensor patented by the Universidad de La Laguna (Canary Islands, Spain): international patent PCT/ES2007/000046 (WIPO publication number WO/2007/082975). It can simultaneously measure the wavefront phase and the distance to the light source in a real-time process. The pipeline algorithm is implemented using Field Programmable Gate Arrays (FPGA). These devices present architecture capable of handling the sensor output stream using a massively parallel approach and they are efficient enough to resolve several Adaptive Optics (AO) problems in Extremely Large Telescopes (ELTs) in terms of processing time requirements. The FPGA implementation of the wavefront phase recovery algorithm using the CAFADIS camera is based on the very fast computation of two dimensional fast Fourier Transforms (FFTs). Thus we have carried out a comparison between our very novel FPGA 2D-FFTa and other implementations

Analysis of the economic feasibility and reduction of a building’s energy consumption and emissions when integrating hybrid solar thermal/PV/micro-CHP systems

The aim of this paper is to assess the performance of several designs of hybrid systems composed of solar thermal collectors, photovoltaic panels and natural gas internal combustion engines. The software TRNSYS 17 has been used to perform all the calculations and data processing, as well as an optimisation of the tank volumes through an add-in coupled with the GENOPT® software. The study is carried out by analysing the behaviour of the designed systems and the conventional case in five different locations of Spain with diverse climatic characteristics, evaluating the same building in all cases. Regulators, manufacturers and energy service engineers are the most interested in these results. Two major contributions in this paper are the calculations of primary energy consumption and emissions and the inclusion of a Life Cycle Cost analysis. A table which shows the order of preference regarding those criteria for each considered case study is also included. This was fulfilled in the interest of comparing between the different configurations and climatic zones so as to obtain conclusions on each of them. The study also illustrates a sensibility analysis regarding energy prices. Finally, the exhaustive literature review, the novel electricity consumption profile of the building and the illustration of the influence of the cogeneration engine working hours are also valuable outputs of this paper, developed in order to address the knowledge gap and the ongoing challenges in the field of distributed generation

Evaluation of a Forest-Grazing System on a Pre-Fattening Cattle Farm

Context: The productivity of cattle production systems has tended to decrease as a consequence of climate change. The forecasts indicate that rainfall must drop by 60%, so the utilization of leguminous trees constitutes a way of improving feed supply and quality. Aim: To evaluate the behavior of a rotational forest-grazing system made of gramineous and leguminous plants (Pennisetum purpureun cv. CT 169 and Sacharum Oficinarum) on a pre-fattening cattle farm. Methods: The study took place at a Cooperative of Credits and Services, on brown-grayish soil. A randomized block design was used. The average weight for treatment A (25 animals) was 232 kg, whereas the animals in treatment B (25 animals) averaged 236 kg (Holstein-Zebu). The animals were weighed on days 90 and 212, and the evaluations were made in the dry season, using SPSS, version 15.1. At the end of the experiment, the following economic criteria were evaluated: Cost of animal purchasing, cost of salary, sales price, the value of production, and cost-effectiveness. Results: The conversions were acceptable, with favorable live-weight gains, especially in treatment B (516 g/day average) throughout the experiment. The economic-productive results of the forest-grazing system were higher than the results observed using the traditional system. Cost-effectiveness was 23.32% higher than the ones produced by the traditional system. Conclusions: Forest-grazing systems are a low-input pre-fattening alternative that permits obtaining gains of over 500g/d when compared to the traditional system

Detección de frente de onda. Aplicación a técnicas de alta resolución espacial y alineamiento de superficies ópticas segmentadas

Dentro del amplio epígrafe "alta resolución espacial" se engloban diversos estudios teóricos y semiempíricos que van desde la descripción y análisis de la turbulencia atmosférica y sus efectos sobre imágenes astronómicas, hasta el proceso de formación de imagen a través de sistemas ópticos. Las llamadas técnicas de alta resolución espacial tienen como objetivo alcanzar el máximo detalle en la estructura de los objetos astronómicos, para lo que resulta esencial el conocimiento de la fase del frente de onda que alcanza el telescopio procedente de tales objetos. Tras una introducción a la representación estadística del proceso real de observación astronómica y a las diversas técnicas de alta resolución espacial, presenta un análisis detallado de los sensores de Hartmann-Shack y de curvatura, así como el diseño y aplicación de diversas modificaciones en algoritmos de restauración de la fase del frente de onda. El desarrollo de simulaciones numéricas de las distintas etapas del proceso de observación constituye una potente herramienta de conocimiento que es ampliamente explotada en este trabajo. El núcleo del mismo consiste en la elaboración de un conjunto computacional que permite la simulación bidimensional del efecto de la turbulencia atmosférica sobre la fase del frente de onda, del funcionamiento de los sensores de Hartmann-Shack y de curvatura, de diversos objetos astronómicos y el resultado de aplicar a los mismos la técnica de deconvolucion con detección de frente de onda y, por ultimo, de la aplicación por separado y de forma conjunta de los dos sensores mencionados al alineamiento de los segmentos de superficies ópticas de grandes telescopios

Heterogeneous resource management in energy hubs with self-consumption: Contributions and application example

The energy hub concept and modeling methodology are widely employed tools for solving resource conversionand storage scheduling problems. For instance, industrial clusters might benefit from determining the suitabletime to operate their facilities and to sell electricity to the public power grid, according to legal, economic orenvironmental factors. In this paper, novel elements are introduced in order to more accurately represent realplants and to reduce the amount of decision variables. The major innovation is to consider devices consuming aresource which is not related to the quantity of output produced, by attaching binary decision variables tocertain energy hub outputs. Secondly, a path vector is defined to take into account the flows of resources withinthe system instead of employing a variable for each branch between the components. The third innovationconsists of an additional vector to express the amount of output resources sold from the energy hub, includingconstraints for those resources which are exported and imported through the same medium. An extended energyhub model is first proposed and then applied to a real plant example, including multiple and heterogeneousresources and performing a comparison between days with different demands, weather conditions and electricityprices. The results obtained in the selected scenarios demonstrate a logical operation scheduling, and thereforevalidate the proposed approach

Architecture, design and source code comparison of ns-2 and ns-3 network simulators

Ns-2 and its successor ns-3 are discrete-event simulators. Ns- 3 is still under development, but offers some interesting characteristics for developers while ns-2 still has a big user base. This paper remarks current differences between both tools from developers point of view. Leaving performance and resources consumption aside, technical issues described in the present paper might help to choose one or another alternative depending of simulation and project management requirements.Ministerio de Educación y Ciencia TIN2006-15617-C03-03Junta de Andalucía P06-TIC-229

Analysis of source code metrics from ns-2 and ns-3 network simulators

Ns-2 and its successor ns-3 are discrete-event simulators which are closely related to each other as they share common background, concepts and similar aims. Ns-3 is still under development, but it offers some interesting characteristics for developers while ns-2 still has a large user base. While other studies have compared different network simulators, focusing on performance measurements, in this paper we adopted a different approach by focusing on technical characteristics and using software metrics to obtain useful conclusions. We chose ns-2 and ns-3 for our case study because of the popularity of the former in research and the increasing use of the latter. This reflects the current situation where ns-3 has emerged as a viable alternative to ns-2 due to its features and design. The paper assesses the current state of both projects and their respective evolution supported by the measurements obtained from a broad set of software metrics. By considering other qualitative characteristics we obtained a summary of technical features of both simulators including, architectural design, software dependencies or documentation policies.Ministerio de Ciencia e Innovación TEC2009-10639-C04-0

Digital literacy and the use of augmented reality in teaching science in Secondary Education

Hoy día la tecnología ocupa un lugar destacado en la sociedad, por lo que es fundamental para desenvolverse en ella con éxito tener adquirida la competencia digital. Los docentes deben desarrollarla de forma adecuada para que su labor educativa sea eficaz y para poder transmitirla a su alumnado. Un ejemplo del uso de la tecnología en educación que se encuentra en auge es la utilización didáctica de la Realidad Aumentada, que ofrece al área de las ciencias una gran cantidad de posibilidades para facilitar el proceso de enseñanza-aprendizaje. El objetivo que se plantea en el presente estudio es conocer la incidencia de la competencia digital en el empleo de la realidad aumentada como recurso didáctico en la impartición de clases relacionadas con las ciencias. El método utilizado es de tipo cuantitativo no experimental, de corte descriptivo, correlacional y con carácter predictivo. La recogida de datos se ha llevado a cabo mediante un cuestionario ad hoc sobre competencia digital docente y realidad aumentada, con diferentes niveles de respuesta. Los resultados muestran que la realidad aumentada es un recurso que ha sido usado por parte de los docentes que imparten ciencias, presentando estos un nivel de competencia digital medio. Se concluye afirmando que los docentes que utilizan la realidad aumentada presentan más competencia digital que aquellos que no lo usan.Today, technology is a major issue in society, so it is essential to have acquired digital competence in order to be successful in it. An example of the growing use of technology in education is the didactic use of Augmented Reality, which offers the area of science a wealth of possibilities to facilitate the teaching-learning process. The aim of this study is to understand the impact of digital competence on the use of augmented reality as a teaching resource in science-related classes. The method used is quantitative, non-experimental, descriptive, correlational and predictive. The data collection has been carried out through an ad hoc questionnaire on digital teaching competence and augmented reality with different levels of response. The results show that augmented reality is a resource that has been used by teachers teaching science, presenting them with an average level of digital competence. We conclude by stating that teachers who use augmented reality are more digitally competent than those who do not.

La formación social tribal en la bahía de Cádiz

Trabajamos en una perspectiva teórica de la Arqueología Social. Se exponen las categorias de análisis básicas para el estudio de la formación social tribal comunitaria en el medio natural de la Bahia de Cádiz en el Holoceno. Se incide en las circunstancias del medionatural y en los datos del registro arqueológico. Se plantean las caracteristicas del proceso histórico hacia el desarrollo de sociedades clasistas iniciales

Diferencias por género en el discurso publicitario impreso de la industria farmacéutica durante los primeros años del México postrevolucionario

This study is based on the idea of “knowledge regimes,” that is, the set of historically constructed meanings about a topic of interest to society through structuring discourses that are presumed valid. Print advertising about medicine that appeared in the Mexican media in the year 1928 was analyzed. Using some of Patrick Charaudeau’s proposals regarding the “contract of communication” in media products as a base, clear differences of gender in regard to the relationship men and women keep in the health-disease binomial were found, as well as the roles derived from this relationship. Various keys of the knowledge regimes currently prevailing in this field were found during this foundational period of mass advertisement associated with the emergence of modernization in Mexico.A partir de la idea de los “regímenes de saber”, es decir, el conjunto de sentidos construidos históricamente sobre algún asunto de interés para la sociedad a través de discursos estructurantes que se imponen como válidos, se analizó la publicidad impresa sobre medicamentos aparecida en la prensa mexicana del año 1928.  Tomando como base algunas propuestas de Patrick Charaudeau acerca del “contrato de comunicación” en los productos mediáticos, se encontraron claras diferencias de género en lo que hace a la relación que mujer y hombre mantienen hacia el binomio salud-enfermedad y los roles que de esta relación se derivan. En esta etapa fundacional de la publicidad masiva asociada el surgimiento de la modernización en México se encuentran algunas claves de los regímenes de saber vigentes en este campo