Optimal investment timing using Markov jump price processes

In this work, we address an investment problem where the investment can either be made immediately or postponed to a later time, in the hope that market conditions become more favourable. In our case, uncertainty is introduced through market price. When the investment is undertaken, a fixed sunk cost must be paid and a series of cash flows are to be received. Therefore, we are faced with an irreversible investment. Real options analysis provides an adequate framework for this type of problems by recognizing these two characteristics, uncertainty and irreversibility, explicitly. We describe algorithmic solutions for this type of problems by modelling market prices evolution by Markov jump processes.Irreversible investment, optimal stopping, dynamic programming, Markov jump processes

Generating Up-to-Date and Detailed Land Use and Land Cover Maps Using OpenStreetMap and GlobeLand30

With the opening up of the Landsat archive, global high resolution land cover maps have begun to appear. However, they often have only a small number of high level land cover classes and they are static products, corresponding to a particular period of time, e.g., the GlobeLand30 (GL30) map for 2010. The OpenStreetMap (OSM), in contrast, consists of a very detailed, dynamically updated, spatial database of mapped features from around the world, but it suffers from incomplete coverage, and layers of overlapping features that are tagged in a variety of ways. However, it clearly has potential for land use and land cover (LULC) mapping. Thus the aim of this paper is to demonstrate how the OSM can be converted into a LULC map and how this OSM-derived LULC map can then be used to first update the GL30 with more recent information and secondly, enhance the information content of the classes. The technique is demonstrated on two study areas where there is availability of OSM data but in locations where authoritative data are lacking, i.e., Kathmandu, Nepal and Dar es Salaam, Tanzania. The GL30 and its updated and enhanced versions are independently validated using a stratified random sample so that the three maps can be compared. The results show that the updated version of GL30 improves in terms of overall accuracy since certain classes were not captured well in the original GL30 (e.g., water in Kathmandu and water/wetlands in Dar es Salaam). In contrast, the enhanced GL30, which contains more detailed urban classes, results in a drop in the overall accuracy, possibly due to the increased number of classes, but the advantages include the appearance of more detailed features, such as the road network, that becomes clearly visible

Late Bronze Age metallic depositions in the AssureiraValley. The case study of Moinhos de Golas site (Solveira, Montalegre, Northern Portugal)

Este trabalho tem como objetivo dar a conhecer um conjunto de achados metálicos do Bronze Final, em asso-ciação com fragmentos cerâmicos e líticos, encontrados no sítio de Moinhos de Golas, freguesia de Solveira, concelho de Montalegre. A coleção metálica é composta por armas, artefactos de adorno, utensílios, possíveis elementos de produção metalúrgica, entre outros objetos de difícil classificação. As análises de composição química a peças seleciona-das, embora preliminares, mostram que a maioria dos artefactos foram produzidos numa liga de bronze binário (Cu-Sn). Pelo facto de terem sido encontradas dispersas por vários lugares do outeiro, este grupo de peças não pode considerar-se um depósito fechado.This work aims to publish a set of metal findings attributed to Bronze Age, and found in association with ceramic and lithic fragments. These were found in the Moinhos de Golas site, Solveira parish, in the Montale-gre council. This set consists of metallic weapons, ornaments, tools, and some objects that might be related to metallurgical processes, among other objects difficult to classify. Preliminary elemental analysis made on selected artefacts point out that most objects were produced in a binary bronze alloy. This set of artefacts, given their finding circumstances, should not be regarded as a closed hoard.Este trabalho foi desenvolvido no âmbito dos projetos Metalurgia Primitiva no Território Português – EARLYMETAL (PTDC/HIST-ARQ/110442/2008) e Espaços Naturais, Arquiteturas, Arte rupestre e Deposições na Pré-história Recente da Fachada Ocidental do Centro e Norte Português: das Ações aos Significados - ENARDAS (PTDC/HISARQ/112983/2009), financiado pelo Programa Operacional Temático Factores de Competitividade (COMPETE) e comparticipados pelo Fundo Comunitário Europeu FEDER. Os autores agradecem à Fundação para a Ciência e a Tecnologia (FCT) as bolsas individuais (SFRH/ BD/65143/2009) e (SFRH/BPD/73245/2010) concedidas a João Fonte e Elin Figueiredo, respetivamente, e o apoio financeiro concedido ao CENIMAT/I3N através do Projecto Estratégico LA25/2013-2014 (PEst-C/CTM/LA0025/2011); a Joe Horst os esclarecimentos gentilmente cedidos sobre as condições de achado; à empresa Metais Jaime Dias, S.A. e ao Dr. Normando Ramos a possibilidade do uso do equipamento de FRX portátil para o estudo preliminar da coleção metálica e à equipa do Museu D. Diogo de Sousa, em Braga, o tratamento e fotografia do conjunto.info:eu-repo/semantics/publishedVersio

Knowledge, Food and Place: a way of producing a way of knowing

The article examines the dynamics of knowledge in the valorisation of local food, drawing on the results from the CORASON project (A cognitive approach to rural sustainable development: the dynamics of expert and lay knowledge), funded by the EU under its Framework Programme 6. It is based on the analysis of several in-depth case studies on food relocalisation carried out in 10 European countries

Boron-10 lined RPCs for sub-millimeter resolution thermal neutron detectors: Feasibility study in a thermal neutron beam

The results of an experimental feasibility study of a position sensitive thermal neutron detector based on a resistive plate chamber (RPC) are presented. The detector prototype features a thin-gap (0.35 mm) hybrid RPC with an aluminium cathode lined with a 2 ${\mu}$m thick $^{10}B{_4}C$ neutron converter layer enriched in $^{10}B$ and a float glass anode. A detection efficiency of ${\approx}$ 6.2 ${\%}$ was measured for the neutron beam (${\lambda}$ =2.5 ${\AA}$) at normal incidence. A spatial resolution better than 0.5 mm FWHM was demonstrated

LATTES: A new gamma-ray detector concept for South America

Currently the detection of Very High Energy gamma-rays for astrophysics rely on the measurement of the Extensive Air Showers (EAS) either using Cherenkov detectors or EAS arrays with larger field of views but also larger energy thresholds. In this talk we present a novel hybrid detector concept for a EAS array with an improved sensitivity in the lower energies (~ 100 GeV). We discuss its main features, capabilities and present preliminary results on its expected perfomances and sensitivities.This wide field of view experiment is planned to be installed at high altitude in South America making it a complementary project to the planned Cherenkov telescope experiments and a powerful tool to trigger further observations of variable sources and to detect transients phenomena