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

Analysis of spinning reserves in systems with variable power sources

In this paper is studied an approach based on risk assessment to solve the scheduling of a power production system with variable power sources. The spinning reserves resulting from the unit commitment are analyzed too. In this methodology there are no infeasible solutions, only more or less costly solutions associated to the operation risks, such as, load or renewable production curtailment. The uncertainty of forecasted production and load demand are defined by probability distribution functions. The methodology is tested in a real case study, an island with high penetration of renewable power production. Finally, forecasted and measured reserves are compared, once the reserves are strongly linked with the forecasting quality. The results of a real case study are presented and discussed. They show the difficulty to achieve complete robust solutions.info:eu-repo/semantics/publishedVersio

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

Insights into nanomedicine for head and neck cancer diagnosis and treatment

Head and neck cancers rank sixth among the most common cancers today, and the survival rate has remained virtually unchanged over the past 25 years, due to late diagnosis and ineffective treatments. They have two main risk factors, tobacco and alcohol, and human papillomavirus infection is a secondary risk factor. These cancers affect areas of the body that are fundamental for the five senses. Therefore, it is necessary to treat them effectively and non-invasively as early as possible, in order to do not compromise vital functions, which is not always possible with conventional treatments (chemotherapy or radiotherapy). In this sense, nanomedicine plays a key role in the treatment and diagnosis of head and neck cancers. Nanomedicine involves using nanocarriers to deliver drugs to sites of action and reducing the necessary doses and possible side effects. The main purpose of this review is to give an overview of the applications of nanocarrier systems to the diagnosis and treatment of head and neck cancer. Herein, several types of delivery strategies, radiation enhancement, inside-out hyperthermia, and theragnostic approaches are addressed.info:eu-repo/semantics/publishedVersio