Abstract

Abstract
Automatic traffic sign recognition is a difficult task, as it is necessary to distinguish between a very high number of classes with low inter-class variability. The state-of-the-art methods report very high accuracy rates but just a few classes are covered and several training samples are required. For the sake of the development of an asset management system, these approaches are out of reach. Furthermore, in this context, minimizing user's effort is more important than achieving maximal classification accuracy. In this paper, we propose a catalogue-based traffic sign classifier which doesn't require real training samples for model building and promotes minimal user's workload involving the catalogue's semantic structure in the error propagation. Experimental results reveal that user's workload was reduced by 20% while accuracy was improved by 2%.

Abstract
This paper presents a comparative study of the influence of different aggregated electrical circuit battery models in the sizing process of a hybrid energy storage system (ESS), composed by Li-ion batteries and supercapacitors (SCs). The aim is to find the number of cells required to propel a certain vehicle over a predefined driving cycle. During this process, three battery models will be considered. The first consists in a linear static zeroeth order battery model over a restricted operating window. The second is a non-linear static model, while the third takes into account first-order dynamics of the battery. Simulation results demonstrate that the adoption of a more accurate battery model in the sizing of hybrid ESSs prevents over-sizing, leading to a reduction in the number of cells of up to 29%, and a cost decrease of up to 10%.

Abstract
This paper contributes to the scarce empirical literature on the impact of foreign ownership on human capital intensity. New evidence is provided, based on a comprehensive, large-scale survey of technology-based firms located in Portugal.The key findings are that: (1) foreign ownership directly (and significantly) impacts a firm's general human capital (education); (2) foreign ownership indirectly (and significantly) impacts a firm's specific human capital (skills); (3) the total impact of foreign ownership on a firm's human capital intensity is higher for education- (general) than for skills- (specific) related human capital intensity. Giving the critical importance of both FDI and human capital development for an 'intermediate' economy like Portugal (lagging behind in terms of human capital stock, and seeming to have lost part of its attractiveness as an FDI location), the paper discusses related policy implications. It is believed that our results and conclusions may be useful for other countries facing similar challenges.

Abstract
Problem: The Adaptive Cruise Control is an Advanced Driver Assistance System (ADAS) that allows maintaining given headway and speed, according to settings pre-defined by the users. Despite the potential benefits associated to the utilization of ACC, previous studies warned against negative behavioral adaptations that might occur while driving with the system activated. Unfortunately, up to now, there are no unanimous results about the effects induced by the usage of ACC on speed and time headway to the vehicle in front. Also, few studies were performed including actual users of ACC among the subjects. Objectives: This research aimed to investigate the effect of the experience gained with ACC on speed and time headway for a group of users of the system. In addition, it explored the impact of ACC usage on speed and time headway for ACC users and regular drivers. Method: A matched sample driving simulator study was planned as a two-way (2 x 2) repeated measures mixed design, with the experience with ACC as between-subjects factor and the driving condition (with ACC and manually) as within-subjects factor. Results: The results show that the usage of ACC brought a small but not significant reduction of speed and, especially, the maintenance of safer time headways, being the latter result greater for ACC users, probably as a consequence of their experience in using the system. Summary: The usage of ACC did not cause any negative behavioral adaptations to the system regarding speed and time headway. Practical applications: Based on this research work, the Adaptive Cruise Control showed the potential to improve road safety for what concerns the speed and the time headway maintained by the drivers. The speed of the surrounding traffic and the minimum time headway settable through the ACC seem to have an important effect on the road safety improvement achievable with the system.

Abstract
A monthly index based on the persistence of the westerly winds over the English Chanel is constructed for 1685-2008 using daily data from ships' logbooks and comprehensive marine meteorological datasets. The so-called Westerly Index (WI) provides the longest instrumental record of atmospheric circulation currently available. Anomalous WI values are associated with spatially coherent climatic signals in temperature and precipitation over large areas of Europe, which are stronger for precipitation than for temperature and in winter and summer than in transitional seasons. Overall, the WI series accord with the known European climatic history, and reveal that the frequency of the westerlies in the eastern Atlantic during the twentieth century and the Late Maunder Minimum was not exceptional in the context of the last three centuries. It is shown that the WI provides additional and complementary information to the North Atlantic Oscillation (NAO) indices. The analysis of WI series during the industrial era indicates an overall good agreement with the winter and high-summer NAO, with the exception of several multidecadal periods of weakened correlation. These decoupled periods between the frequency and the intensity of the zonal flow are interpreted on the basis of several sources of non-stationarity affecting the centres of the variability of the North Atlantic and their teleconnections. Comparisons with NAO reconstructions and long instrumental indices extending back to the seventeenth century suggest that similar situations have occurred in the past, which call for caution when reconstructing the past atmospheric circulation from climatic proxies. The robustness and extension of its climatic signal, the length of the series and its instrumental nature make the WI an excellent benchmark for proxy calibration in Europe and Greenland.