VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad

Acta de congresoLa conmemoración de los cien años de la Reforma Universitaria de 1918 se presentó como una ocasión propicia para debatir el rol de la historia, la teoría y la crítica en la formación y en la práctica profesional de diseñadores, arquitectos y urbanistas. En ese marco el VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad constituyó un espacio de intercambio y reflexión cuya realización ha sido posible gracias a la colaboración entre Facultades de Arquitectura, Urbanismo y Diseño de la Universidad Nacional y la Facultad de Arquitectura de la Universidad Católica de Córdoba, contando además con la activa participación de mayoría de las Facultades, Centros e Institutos de Historia de la Arquitectura del país y la región. Orientado en su convocatoria tanto a docentes como a estudiantes de Arquitectura y Diseño Industrial de todos los niveles de la FAUD-UNC promovió el debate de ideas a partir de experiencias concretas en instancias tales como mesas temáticas de carácter interdisciplinario, que adoptaron la modalidad de presentación de ponencias, entre otras actividades. En el ámbito de VIII Encuentro, desarrollado en la sede Ciudad Universitaria de Córdoba, se desplegaron numerosas posiciones sobre la enseñanza, la investigación y la formación en historia, teoría y crítica del diseño, la arquitectura y la ciudad; sumándose el aporte realizado a través de sus respectivas conferencias de Ana Clarisa Agüero, Bibiana Cicutti, Fernando Aliata y Alberto Petrina. El conjunto de ponencias que se publican en este Repositorio de la UNC son el resultado de dos intensas jornadas de exposiciones, cuyos contenidos han posibilitado actualizar viejos dilemas y promover nuevos debates. El evento recibió el apoyo de las autoridades de la FAUD-UNC, en especial de la Secretaría de Investigación y de la Biblioteca de nuestra casa, como así también de la Facultad de Arquitectura de la UCC; va para todos ellos un especial agradecimiento

Program AHRES and its Contribution to Assess Features and Current Limitations of Hybrid Rocket Propulsion

In the year 2011 the German Aerospace Center (DLR) has started the program AHRES (Advanced Hybrid Rocket Engine Simulation). The aim is the development of software engineering tools and CFD tools for conceptual design and optimisation of hybrid rocket engines (HRE). To provide high accuracy software tools, the AHRES program includes complex experiments with hybrid rocket engines in laboratory and prototype scale, for pressures up to 70 bars. For this purpose an existing test facility at the DLR site Trauen (former EUROPA 2 upper stage test range) was enhanced, in order to conduct tests with a HRE. In this paper a short description of the operational test bed is given, which is equipped with sophisticated measurement techniques. The HRE test bed is currently equipped with oxidiser supply systems for high-test peroxide (HTP) and gaseous oxygen. The solid fuel grains are based on hydroxyl-terminated polybutadiene (HTPB) mixed with different metallic additives to improve the performance. Currently conducted tests are aimed to characterise the HRE’s combustion processes and to generate an experimental database to develop the above mentioned simulation tools. Based on experimental test data, calculations on developed simulation tools and literature sources a comparison of the HRE with solid and storable liquid rocket engines is made. To illustrate one possible application of a HRE in near-future a HRE which could be applied as an upper stage is designed and compared with existing solid rocket engines. For the comparison the third stage “Zefiro 9A” of the VEGA launcher is taken. The preliminary results and conclusions are presented, including specific impulse, combustion and engine efficiency, as well as the achievable regression rate dependent on fuel composition. The last factor is of tremendous importance to determine the achievable thrust level of a hybrid rocket engine. This again, determines whether a HRE might be promising for the application as an upper stage. The results are presented graphically, in table form, analysed, and commented

Experimental Evaluation of a High Test Peroxide Catalyst Chamber for a Hybrid Rocket Engine

Hybrid rocket propulsion technology has recently gained in importance. Within the program “AHRES” at the German Aerospace Center (DLR), a small HRE technology demonstrator was developed, which should deliver data for the validation of a self-developed HRE design software. Instead of a conventional ignition system, for this HRE a catalyst chamber with a silver mesh catalyst is designed to decompose currently up to 0.7 kg/s of 87.5% HTP to steam and oxygen at high temperatures. The chamber consists of the catalyst itself, a mount for the catalyst material, a retainer, an injector manifold, a cooling channel, and a casing. Furthermore, a pressure sensor, a mass flow sensor, and a thermocouple are attached to measure the properties of the decomposition products. The chamber is mounted on a test-bed which comprises attachment, peroxide storage, feed system, valves, data acquisition, and control. By determination of the decomposition temperature, the integrity of decomposition is verified and compared to theoretical prediction. The catalyst chamber is developed based on the results of the design tool SHAKIRA. Several calculations are carried out to determine the appropriate geometry for complete decomposition with a minimum of catalyst material. The experimental results show good agreement to the results generated by the design tool. The developed and tested catalyst chamber provides a simple, reliable ignition system for hybrid rocket engine based on hydrogen peroxide as oxidiser. The system is capable of igniting repeatedly without the need to meet an optimal ignition point. Such a system behaves like a hypergolic engine in terms of ignition, but no hazardous substances are required

Minimally Invasive Projector Calibration for 3D Applications

Abstract: Addressing the typically time consuming adjustment of projector equipment in VR in-stallations we propose an easy to implement projector calibration method that effectively corrects images projected onto planar surfaces and which does not require any additional hardware. For hardware accelerated 3D applications only the projection matrix has to be modified slightly thus there is no performance impact and existing applications can be adopted easily

Ultrastructural study of the relationship between generative and vegetative cells inMagnolia ×soulangeana Soul.-Bod. pollen grains

Summary InMagnolia ×soulangeana pollen grains the generative cell (GC) does not become totally free within the vegetative cell (VC), at least until the pollen tube emergence. Due to a deviation in its detachment process from the sporoderm, the opposing ends of the VC plasmalemma do not fuse themselves when the GC moves away from the intine. Consequently, the interplasmalemmic space surrounding the GC does not become isolated but rather maintains continuity with the sporoderm through a complex formation that we have called plasmalemmic cord. The real existence of this formation was confirmed through serial sectioning showing the plasmalemmic cord to consist of the VC plasmalemma. In its initial portion it is occupied by a reasonably accentuated wall ingrowth of the inner layer of the intine (intine 3). In the remainder portion, neither of the cytochemical tests used in this work have revealed the presence of a significant amount of wall material. However, ultrathin sections of samples processed either chemically or by cryofixation showed the existence of an intricate system of tubules and vesicles, some of which are evaginations of the VC plasmalemma. The hypothesis that the plasmalemmic cord may have a role in the complex interactions between the two pollen cells is discussed

Pollen tube taxol dependent structures co-assemble with neuronal HMW MAPs (MAP2)

Pollen tube microtubules (MTs) are as dynamic as animal MTs and they may interact with plasma membrane, endoplasmic reticulum, Golgi apparatus, mitocondria and a variety of cytoplasmic proteins. Bridges connecting MTs to each other and to membranes have been documented in pollen tubes by electron microscopy; however, the biochemical and molecular nature of these linkages is not known. In other cell types interaction between organelles and MTs require the participation of Microtubule-Associated Proteins (MAPs) that bridge the cytoskeleton to these organelles. Although biochemical documentation of such bridging MAPs in plant cells is lacking, it is reasonable to assume, by analogy with the animal systems, that specialized MAPs regulate MTs polymerization and dynamic in pollen tube. As a first step toward testing this hypothesis, the ability of Nicotiana tabacum pollen tube taxol-stabilized MTs to bind mammalian brain High Molecular Weight MAPs (HMWMAPs)(MAP2) was tested. This association analysis revealed the presence of mammalian MAP2-binding sites on pollen tube taxol-induced structures suggesting that the association presumably occurs at conserved domains on the tubulin molecules