Abstract
Rekindles can represent a high burden on wildland fire suppression resources, but despite the relevance of this phenomenon in Portugal, related research is still scarce. Seeking to contribute to address this gap, the purpose of this study was to organize and provide an overview of the problem of rekindles in Portugal, and to verify whether evidence exists that the high proportion of rekindles in Portugal is related to the double duty of Portuguese firefighters to perform initial attack and mop-up operations. Our study included informal meetings, formal recorded interviews, dispatch centre visits, actual rekindle observation, and an analysis of the National Forest Authority database. From the study of genealogies of rekindles, we concluded that 17.2% additional forest fires (rekindles in successive generations) had their origin in only 7.4% of primary fires. Through linear regression analysis, we found that their proportions increase in days with more occurrences, preliminarily supporting the hypothesis of premature abandonment of mop-up operations, as a result from the pressure to immediately attack starting fires by the same crews. A more detailed analysis of two representative districts highlighted specific organizational and natural challenges to successful mop-up efforts and provided further evidence of the hazardousness of rekindles. © 2012 WIT Press.

Abstract
This paper reports the lessons learnt about the benefits of using a formal verification tool like PVS to support field studies. The presentation is based on a field study in the healthcare domain which was designed to investigate the resilience of human behaviour in an oncology ward of a hospital. The automated reasoning tool PVS was used systematically to compare actual practice observed during the field study with normative behaviour described for example by user manuals for the devices involved. The approach helped (i) identify latent situations that could lead to hazard, and (ii) suggest situations likely to warrant further investigation as part of the field study. The main contribution of this paper is a set of detailed examples that illustrate how we used PVS during the field study, and how the tool led to insights. © 2012 Springer-Verlag.

Abstract

Abstract
Spreadsheets are widely recognized as popular programming systems with a huge number of spreadsheets being created every day. Also, spreadsheets are often used in the decision processes of profit-oriented companies. While this illustrates their practical importance, studies have shown that up to 90% of real-world spreadsheets contain errors. © 2012 IEEE.

Abstract
In highly populated urban zones, it is common to notice headway deviations (HD) between pairs of buses. When these events occur in a bus stop, they often cause bus bunching (BB) in the following bus stops. Several proposals have been suggested to mitigate this problem. In this paper, we propose to find BBS (Bunching Black Spots) - sequences of bus stops where systematic HD events cause the formation of BB. We run a sequence mining algorithm, named PrefixSpan, to find interesting events available in time series. We prove that we can accurately model the BB trip usual pattern like a frequent sequence mining problem. The subsequences proved to be a promising way of identify the route' schedule points to adjust in order to mitigate such events. © 2012 Springer-Verlag.

Abstract
A high sensitivity Fabry-Perot (FP) strain sensor based on hollow-core ring photonic crystal fiber was investigated. A low-finesse FP cavity was fabricated by splicing a section of hollow-core ring photonic crystal fiber between two standard single mode fibers. The geometry presents a low cross section area of silica enabling to achieve high strain sensitivity. Strain measurements were performed by considering the FP cavity length in a range of 1000 mu m. The total length of the strain gauge at which strain was applied was also studied for a range of 900 mm. The FP cavity length variation highly influenced the strain sensitivity, and for a length of 13 mu m a sensitivity of 15.4 pm/mu epsilon was attained. Relatively to the strain gauge length, its dependence to strain sensitivity is low. Finally, the FP cavity presented residual temperature sensitivity (similar to 0.81 pm/degrees C). (C) 2012 Optical Society of America