Deep neural network recognition of shallow water corals in the Gulf of Eilat (Aqaba)

AbstractWe describe the application of the computerized deep learning methodology to the recognition of corals in a shallow reef in the Gulf of Eilat, Red Sea. This project is aimed at applying deep neural network analysis, based on thousands of underwater images, to the automatic recognition of some common species among the 100 species reported to be found in the Eilat coral reefs. This is a challenging task, since even in the same colony, corals exhibit significant within-species morphological variability, in terms of age, depth, current, light, geographic location, and inter-specific competition. Since deep learning procedures are based on photographic images, the task is further challenged by image quality, distance from the object, angle of view, and light conditions. We produced a large dataset of over 5,000 coral images that were classified into 11 species in the present automated deep learning classification scheme. We demonstrate the efficiency and reliability of the method, as compared to painstaking manual classification. Specifically, we demonstrated that this method is readily adaptable to include additional species, thereby providing an excellent tool for future studies in the region, that would allow for real time monitoring the detrimental effects of global climate change and anthropogenic impacts on the coral reefs of the Gulf of Eilat and elsewhere, and that would help assess the success of various bioremediation efforts.</jats:p

Conflicto entre judíos y conversos en Aragón tras los tumultos de 1391: nuevos testimonios extraídos de la colección epistolar de Yom Tob Ben Ḥanná de Montalbán

Study and edition of a letter written in rhymed prose contained in the epistolographic formulary by Yom Tov Ben Ḥannah, scribe to the Jewish community of Montalbán, in the Kingdom of Aragon. Written a few years after 1391 by the scribe on behalf of the local aljama, the letter was sent to the trustees of the Jewish community of Daroca, and its purpose was to collect money from Yosef Caro, a Jewish smith who had fled from Montalbán to there, following a dispute with another elderly smith who was an apostate. A reading of the Hebrew text shows that the conflict goes beyond a simple dispute between craftsmen, and involves a clash between Jews and their former brethren. This new phenomenon of mass conversion is also corroborated by a Hebrew poem of the Montalbán’s Jewish scribe that is edited and translated in addition. The analysis of the text reflects the tension between Jews and converts in the aftermath of the 1391 riots.Poco después de los tumultos de 1391, los responsables de la aljama aragonesa de Montalbán remitían a los de la de Daroca una carta escrita por el escriba local e incluida en la colección epistolar de Yom Tob Ben Ḥanná. El propósito de esa carta era solicitar dinero de Yosef Caro, artesano judío de Montalbán, que había huido a Daroca a consecuencia de una disputa con otro artesano judío apóstata. El análisis del texto hebreo que aquí se edita muestra que el conflicto trasciende la simple disputa profesional, y debe entenderse en el marco de disputas entre judíos y sus antiguos correligionarios, ahora cristianos. La tensión entre judíos y conversos aparece corroborada por un poema hebreo de este escriba judío de Montalbán, que también se edita y traduce