Globalizations for partial (co)actions on coalgebras

In this paper, we introduce the notion of globalization for partial module coalgebra and for partial comodule coalgebra. We show that every partial module coalgebra is globalizable exhibiting a standard globalization. We also show the existence of globalization for a partial comodule coalgebra, provided a certain rationality condition. Moreover, we show a relationship between the globalization for the (co)module coalgebra and the usual globalization for the (co)module algebra.Comment: 31 page

Multidisciplinary design and flight testing of a remote gas/particle airborne sensor system

The main objective of this paper is to describe the development of a remote sensing airborne air sampling system for Unmanned Aerial Systems (UAS) and provide the capability for the detection of particle and gas concentrations in real time over remote locations. The design of the air sampling methodology started by defining system architecture, and then by selecting and integrating each subsystem. A multifunctional air sampling instrument, with capability for simultaneous measurement of particle and gas concentrations was modified and integrated with ARCAA’s Flamingo UAS platform and communications protocols. As result of the integration process, a system capable of both real time geo-location monitoring and indexed-link sampling was obtained. Wind tunnel tests were conducted in order to evaluate the performance of the air sampling instrument in controlled nonstationary conditions at the typical operational velocities of the UAS platform. Once the remote fully operative air sampling system was obtained, the problem of mission design was analyzed through the simulation of different scenarios. Furthermore, flight tests of the complete air sampling system were then conducted to check the dynamic characteristics of the UAS with the air sampling system and to prove its capability to perform an air sampling mission following a specific flight path

On partial (Co)actions on coalgebras : globalizations and some galois theory

Partial module coalgebra and partial comodule coalgebra are the dual notions of partial module algebra, and all these structures are close related. Partial module algebra was defined by Caenepeel and Janssen in [11] and developed in a certain direction by Alves and Batista in [1–3]. We are interested in some constructions made by Alves and Batista, namely: globalization for partial module algebras, a Morita context relating the invariant subalgebra and the partial smash product, and Galois theory. In this work, we introduce the notion of globalization for partial module coalgebra and for partial comodule coalgebra. We show that every partial module coalgebra is globalizable constructing a globalization, named standard. For the case of partial comodule coalgebra we need assume some kind of rationality condition to obtain a correspondent globalization. Moreover, for a partial comodule coalgebra, we construct a Morita-Takeuchi context relating the coinvariant coalgebra and the partial smash coproduct, and we define a Galois coextension and show some properties, relating the Galois coextension for partial comodule coalgebra with the Galois extension for partial coaction on algebras, extending results of Dascalescu, Raianu, and Zhang obtained in [20]

Diseño y modelado de un manipulador serial redundante de siete grados de libertad, apto para efectuar una interacción física segura entre humano y robot

En este proyecto se presenta el diseño y modelado virtual de un manipulador serial con siete grados de libertad con el fin de generar antecedentes en la facultad de Ingeniería mecánica en cuanto a la utilización de manipuladores redundantes, explorando su morfología, comportamiento cinemático y su posibilidad de construcción a bajos costos. Como resultado de este proyecto se obtiene un prototipo virtual modelado en Solidworks así como los modelos matemáticos de la cinemática inversa y directa, aportes que servirán para la futura investigación enfocada en generación de trayectorias para la evasión de obstáculos en un entorno colaborativo

Tiempo y eternidad en el libro XI de Las Confesiones de San Agustín.

Tesis (Licenciado en Filosofía)RESUMEN: El libro XI de las Confesiones de San Agustin, se presenta una pregunta que ha llamado la atención por mucho tiempo a la filosofía: "¿Qué es, pues, el tiempo? Si nadie me lo pregunta, lo sé; si alguien me lo pregunta y quiero explicarlo, ya no lo sé" (Confesiones, XI, 14, 17). Nuestro estudio aborda este problema introduciendo la reflexión acerca de la eternidad, segmento que Husserl aisla de su reflexión del tiempo. Sin negar esa exclusión realizada por parte de dicho autor, nosotros la introducimos, ya que nuestra preocupación se centra en permanecer atento a las relaciones entre eternidad y tiempo que allí son exploradas por san Agustín. ¿Qué significación puede tener esta tensión entre tiempo y eternidad para la comprensión de la experiencia humana del tiempo?, es la pregunta que nos guiara durante la extensión de nuestro estudio. Nuestro estudio estará en un primer capitulo centrado en explicitar el modo en que abordamos la reflexión entre eternidad y tiempo, para luego abordar el tema de la creación que enmarca la reflexión de la eternidad y tiempo. Después en el segundo capitulo, se adentra en la problemática del tiempo, atendiendo a las aportas que Agustin nos hace explicitas cuando se piensa al tiempo. Ésta reflexión, nos conduce a tratar por separado en el capítulo tercero a la tesis resolutoria para las aporías del tiempo que Agustín nos ha presentado, la distentio animi es presentada en ésta primera instancia. La distentio animi es profundizada en el cuarto capitulo, para tratar la filiación de eternidad y tiempo distentio animi, con el objetivo de hacer presente el sentido que puede tener su consideración de la eternidad para una comprensión de la experiencia humana del tiempo. Asumiendo dicha pregunta como la pregunta guia de nuestro estudio, cabe señalar que éste se desarrollará esencialmente como un ejercicio de lectura que seguirá, tanto analitica como interpretativamente, los desplazamientos más significativos del libro en cuestión en lo que respecta al tratamiento de la problemática resaltada. La puesta en relieve de estos desplazamientos nos permite proponer el ante dicho itinerario

Novel Axisymmetric Diffusion Bonded Recuperator for Gas Turbines

The small gas turbines systems, arbitrary categorized as microturbines (5-200 kW) and miniturbines (200-500 kW) are the current most economical solution for the distributed power generation market. The thermal efficiency of such microturbines without and with a recuperator is about 20 and 40% respectively, thus a recuperator is mandatory to reach higher cycle efficiencies. However, the recuperator accounts for about 25-30% of the turbine total cost and its temperature and pressure are constrained depending on the material and construction method, being the bottleneck of the improvement and advancement of this kind of power generation plant. Thus, the actual focus is to develop high performance recuperators able to withstand high temperatures and pressure at minimum cost. There are several different recuperators present on the market, each with their own heat transfer surface and manufacturing method, but all present drawbacks and are relatively old compared to the actual manufacturing methods. For instance, the rectangular offset strip fin geometry, which is one of the highest performance surfaces, is expensive to manufacture and weak to withstand temperature and pressure due to brazing requirements. Hence, in this thesis, a completely novel modular axisymmetric recuperator concept is proposed, joined by diffusion bonding technique, one of the current most advanced heat exchanger manufacturing methods. For the recuperator core, a novel heat transfer surface is proposed based in the rectangular offset strip fins, the thermal and hydraulic characteristics of which were determined experimentally. The devised heat transfer and pressure drop correlations show 85% agreement with the experimental data in the range of 500<3000. A code for the recuperator design, using entropy generation minimization, was developed to predict the recuperator performance and size the optimum recuperator core dimensions. The design code was validated with CFD which in turn was validated with experimental data. The heat transfer and pressure drop CFD results agreed the experimental data with deviation within 3.2% and 27.7%, respectively, and the design code agreed the CFD results with deviation within 0.9% and 11.9%, respectively. Four recuperator study cases for different turbine sizes, 100kW, 100kW_beta, 1250kW and 5000kW, were designed using the design code. The results show the proposed concept can achieve high effectiveness (~90%) with low pressure drop (<4%) with a volume compatible with the current recuperators. Furthermore, the novel recuperator concept has a list of advantages, which makes attractive its application on the future gas turbines, encouraging the research continuity of the proposed concept