Techniques for Area Discretization and Coverage in Aerial Photography for Precision Agriculture employing mini quad-rotors

Remote sensed imagery acquired with mini aerial vehicles, in conjunction with GIS technology enable a meticulous analysis from surveyed agricultural sites. This paper sums up the ongoing work in area discretization and coverage with mini quad-­?rotors applied to Precision Agriculture practices under the project RHEA.

Reality bites: Documentary photography and architectural realism = Fragmentos de realidad: Fotografía documental y realismo en arquitectura

En el día de hoy nos enfrentamos a una serie de desafíos económicos, geopolíticos y ambientales que apuntan hacia una transformación profunda del mundo tal y como lo conocemos. La arquitectura esta – siempre lo ha estado – imbricada en todos estos problemas. En nuestra actual condición de recursos limitados e injusticia global surge la necesidad de superar la dicotomía entre progreso y tradición, entre innovación y preservación – la urgencia de redefinir incluso cada uno de estos términos. Los tipos de crisis que encaramos ahora no se resolverán con mas tecnología y más crecimiento – se necesita también una profunda reevaluación de nuestros sistemas de valores e incluso de nuestra sensibilidad. En este contexto, la humilde contribución de esta tesis consiste en proponer la idea de un realismo en arquitectura, entendido como una actitud progresista y atenta a lo que ya existe, dispuesta a abrir los ojos al presente, a las condiciones y los problemas reales que nos rodean. Pensando en esta idea, resulta evidente que si bien el realismo carece de una definición clara en el campo de la arquitectura hoy, cuenta sin embargo con numerosos precedentes parciales, entre ellos algunos de los más notorios episodios de la historia de la arquitectura reciente. Al intentar confeccionar una lista provisional de arquitectos realistas en el último siglo, otro hecho se nos presenta: muchos, por no decir todos estos arquitectos, comparten una fijación por la fotografía, bien apropiándose del trabajo de fotógrafos contemporáneos, bien tomando sus propias imágenes como una forma de mirar fuera de sus estudios e incorporar la realidad del medio construido a sus proyectos. Parece entonces lógico pensar que la arquitectura, como disciplina visual, ha acudido a otra disciplina visual en búsqueda de su propia respuesta al problema del realismo – dentro de este campo la fotografía reverbera con la arquitectura especialmente, ya que ambas son consideradas simultáneamente como practicas utilitarias y como parte de las bellas artes. Parece entonces lógico el organizar la investigación como una serie de casos, con la esperanza de que la acumulación de diversas instancias en las que la arquitectura ha acudido a la fotografía en su búsqueda de un realismo arrojara luz sobre las ideas más generales a debate. Por tanto, cada uno de los episodios en este texto se examina en sus propios términos, si bien una serie de interconexiones emergen a medida que el estudio procede con un suave orden cronológico. Hacia el final del texto cuestiones más grandes recobran protagonismo, a medida que las repercusiones políticas de nuestro estudio se hacen más patentes y comenzamos a interrogar las implicaciones contemporáneas y el potencial futuro de nuestra discusión sobre el realismo. ABSTRACT Today we are faced with a series of economic, geopolitical and environmental challenges that outline a deep transformation of the world as we know it. Architecture is – it has always been – ingrained in all of these problems. In our current condition of limited resources and global inequalities there is a necessity to overcome the dichotomy between progress and tradition, between innovation and preservation – an urgency to even redefine these terms altogether. The types of crises that we are facing will not be solved with more technology and more growth – a deep reevaluation of our systems of values and our sensibilities are also needed. In this context, the humble contribution of this text is to put forward the idea of an architectural realism, understood as an attitude that is both progressive and attentive to what is already in place, willing to open its eyes to the present and accept the real conditions and problems around us. In thinking about this prospect, it immediately becomes apparent that even if realism lacks a clear definition in the field of architecture today, there are numerous partial precedents for it, among them some of the most notorious episodes in the recent history of architecture. In crafting a tentative list of realist architects in the last century, another realization takes place: many, not to say all of these architects, have had a fixation with photography, either appropriating the work of contemporary photographers or taking photographs themselves as a way to look out their windows and bring the reality of the built environment into their practices. It seems then logical to think that architecture, as a visual discipline, has looked to other visual disciplines in search for its own take on the problem of realism – within this field, photography specially resonates with architecture, since both are regarded simultaneously as utilitarian practices and belonging to the fine arts. The idea then becomes to organize the research as a series of cases, with the hope that the accumulation of diverse instances in which architecture has approached photography in its realist drive will shed some light on the larger ideas at stake. Therefore, each of the episodes in this text is examined on its own terms, with a series of interconnections slowly emerging as our survey proceeds with a soft chronologic order. Towards the end of the study, larger issues regain relevance as the political repercussions of our inquiry become more pressing and we start to question the contemporary implications and future potentials of our discussion on realism.

Comparative analysis of the relationship between anterior and posterior corneal shape analyzed by Scheimpflug photography in normal and keratoconus eyes

Background To analyze and compare the relationship between anterior and posterior corneal shape evaluated by a tomographic system combining the Scheimpflug photography and Placido-disc in keratoconus and normal healthy eyes, as well as to evaluate its potential diagnostic value. Methods Comparative case series including a sample of 161 eyes of 161 subjects with ages ranging from 7 to 66 years and divided into two groups: normal group including 100 healthy eyes of 100 subjects, and keratoconus group including 61 keratoconus eyes of 61 patients. All eyes received a comprehensive ophthalmologic examination including an anterior segment analysis with the Sirius system (CSO). Antero-posterior ratios for corneal curvature (k ratio) and shape factor (p ratio) were calculated. Logistic regression analysis was used to evaluate if some antero–posterior ratios combined with other clinical parameters were predictors of the presence of keratoconus. Results No statistically significant differences between groups were found in the antero–posterior k ratios for 3-, 5- and 7-mm diameter corneal areas (p ≥ 0.09). The antero–posterior p ratio for 4.5- and 8-mm diameter corneal areas was significantly higher in the normal group than in the keratoconus group (p < 0.01). The k ratio for 3, 5, and 7 mm was significantly higher in the keratoconus grade IV subgroup than in the normal group (p < 0.01). Furthermore, significant differences were found in the p ratio between the normal group and the keratoconus grade II subgroup (p ≤ 0.01). Finally, the logistic regression analysis identified as significant independent predictors of the presence of keratoconus (p < 0.01) the 8-mm anterior shape factor, the anterior chamber depth, and the minimal corneal thickness. Conclusions The antero-posterior k and p ratios are parameters with poor prediction ability for keratoconus, in spite of the trend to the presence of more prolate posterior corneal surfaces compared to the anterior in keratoconus eyes.

Catalogue of Chinese rubbings from Field Museum / researched by Hoshien Tchen, M. Kenneth Starr ; prepared by Alice K. Schneider ; photographs by Herta Newton, and Field Museum Division of Photography ; edited by Hartmut Walravens.

n.s. no.3(1981)