Browsing by Issue Date, starting with "2016-08"
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- Digital Forensic Artifacts of the Cortana Device Search Cache on Windows 10 DesktopPublication . Domingues, Patrício; Frade, MiguelMicrosoft Windows 10 Desktop edition has brought some new features and updated other ones that are of special interest to digital forensics analysis. The search box available on the taskbar, next to the Windows start button is one of these novelties. Although the primary usage of this search box is to act as an interface to the intelligent personal digital assistant Cortana, in this paper, we study the digital forensic artifacts of the search box on machines when Cortana is explicitly disabled. Specifically, we locate, characterize and analyze the content and dynamics of the JSON-based files that are periodically generated by the Cortana device search cache system. Forensically important data from these JSON files include the number of times each installed application has been run, the date of the last execution and the content of the custom jump list of the applications. Since these data are collected per user and saved in a resilient text format, they can help in digital forensics, mostly in assisting the validation of other sources of information.
- Measurement tool to assess the relationship between corporate social responsibility, training practices and business performancePublication . Ferraz, Francisco António Vaz Guedes Delgado; Gallardo-Vázquez, DoloresSocially responsible actions are increasingly required of companies and are seen as a valid response to new challenges in contemporary societies. These substantial challenges encourage the development of best practices within organisations, requiring extensive verification and analysis of these practices' influence and impact. The objective of this paper is to define and present the validation of a set of scales for the measurement of social responsibility, training practices and performance in companies. This approach facilitates a better understanding of the competitive advantages of implementing these practices. To achieve this objective, the scales of measurement were defined based on the adoption of responsible business behaviours and, concurrently, their observed relationship to training practices and business performance. The results obtained substantiate measurement scales with a total of 26 indicators, which were validated with companies from the Portuguese tourism industry. The discussion of the results shows that these agree with previous research in the literature on the importance of the topics under study. This paper's conclusions are in accordance with theoretical currents in this area, reinforcing findings of the benefits of companies' practices in training and other relevant areas. Finally, the study provides scales adapted to the day-to-day realities of businesses in their natural contexts.
- A new approach for computing a flood vulnerability index using cluster analysisPublication . Fernandez, Paulo; Mourato, Sandra; Moreira, Madalena; Pereira, LuísaA Flood Vulnerability Index (FloodVI) was developed using Principal Component Analysis (PCA) and a new aggregation method based on Cluster Analysis (CA). PCA simplifies a large number of variables into a few uncorrelated factors representing the social, economic, physical and environmental dimensions of vulnerability. CA groups areas that have the same characteristics in terms of vulnerability into vulnerability classes. The grouping of the areas determines their classification contrary to other aggregation methods in which the areas' classification determines their grouping. While other aggregation methods distribute the areas into classes, in an artificial manner, by imposing a certain probability for an area to belong to a certain class, as determined by the assumption that the aggregation measure used is normally distributed, CA does not constrain the distribution of the areas by the classes. FloodVI was designed at the neighbourhood level and was applied to the Portuguese municipality of Vila Nova de Gaia where several flood events have taken place in the recent past. The FloodVI sensitivity was assessed using three different aggregation methods: the sum of component scores, the first component score and the weighted sum of component scores. The results highlight the sensitivity of the FloodVI to different aggregation methods. Both sum of component scores and weighted sum of component scores have shown similar results. The first component score aggregation method classifies almost all areas as having medium vulnerability and finally the results obtained using the CA show a distinct differentiation of the vulnerability where hot spots can be clearly identified. The information provided by records of previous flood events corroborate the results obtained with CA, because the inundated areas with greater damages are those that are identified as high and very high vulnerability areas by CA. This supports the fact that CA provides a reliable FloodVI.
- A climate change adaptive dynamic programming approach to optimize eucalypt stand management scheduling: a Portuguese applicationPublication . Ferreira, L.; Constantino, M.; Borges, J.G.; Garcia-Gonzalo, J.; Barreiro, S.The aim of this paper is to present approaches to optimize stand-level, short-rotation coppice management planning, taking into account uncertainty in stand growth due to climate change. The focus is on addressing growth uncertainty through a range of climate scenarios so that an adaptive capacity may be possible and the vulnerability of the stand to climate change may be reduced. The optimization encompasses finding both the harvest age in each cycle and the number of coppice cycles within a full rotation that maximize net present revenue. The innovation lies in the combination of the process-based model (Glob3PG) with two dynamic programming (DP) approaches. The former is able to project growth of eucalypt stands under climate change scenarios. The innovative approaches are thus influential to define the management policy (e.g., stool thinning, number of coppice cycles, and cycle length) that maximizes net present revenue taking into account uncertainty in forest growth due to climate change. In both approaches, the state of the system is defined by the number of years since plantation, whereas DP stages are defined by the cumulative number of harvests. The first approach proposes the optimal policy under each climate change scenario at each state. The second approach addresses further situations when the climate scenario is unknown at the beginning of the planning horizon. Both help address uncertainty in an adaptive framework, as a set of readily available options is proposed for each scenario. Results of an application to a typical Eucalyptus globulus Labill. stand in central Portugal are discussed.
- Investigação qualitativa na área da saúde: por quê?Publication . Ribeiro, Jaime; Souza, Dayse Neri de; Costa, António Pedro
- Seismic behavior of RC building structures designed according to current codesPublication . Mosleh, A.; Rodrigues, Hugo; Varum, H.; Costa, A.; Arêde, A.Earthquakeswhich recently occurred in highly populated regions showthat existing buildings constructed without appropriate seismic resisting characteristics may constitute as an important source of risk and may cause economical loses and casualties. It is recognized the progress of the knowledge in earthquake engineering in the last decades. In this paper, two 6 irregular storey buildings were studied consisting of frame structures, representative of the common practice in Portugal, i.e. designed without considering earthquake actions. Push-over and non-linear time history analyses were done, with non-inear 3-D models in longitudinal and transverse directions. The building responseswere analyzed in two different levels: global and local. For the global response analyses: max displacement, inter-storey drift (IS drift), floor rotation for each storey and base shear were compared. For local response four columns were chosen and the variation of axial load in terms of base shear and drift as well as the biaxial demand was considered. The result shows that most variation of axial load happens in corner, facade-X, facade-Y and centre column respectively. It is noteworthy that by increasing the initial axial load the biaxial demand decreases. The seismic vulnerability was analyzed for earthquake of different return periods, and the seismic demands were compared with limit proposed in international codes and conclusion are drafted in terms of safety. The vulnerability assessment based on seismic codes clearly shows that the building 2 presented a better performance with low inter-storey drifts. The main goal of this study is considering the application andmethodology for the seismic assessment of existent real buildings. In fact this is an important topic, to understand the seismic vulnerability of certain particularities in existing buildings to assure that the common observation can be applied for a prototype building, especially irregular ones. Also one of the major observations in this study is the comprehension of the effect and importance of biaxial loading in columns and the influence of the axial load variation, relating the position of the columns in plan and in height.
- Mechanical Properties of Injection-Molded Glass Microsphere-Reinforced PolyamidePublication . Capela, Carlos; Ferreira, J. M.; Costa, J. M.; Mendes, N.This paper presents new studies of the physical and mechanical characterization of PA6 matrix composites with different volume fractions of glass microspheres (10, 15, 20, 25 and 30%), which have been processed in an industrial environment. The mechanical properties of different processed composites were obtained by three-point bending tests, and the influence of the time of immersion in water in the strength and modulus was analyzed. The mechanical properties obtained in static tests and DMA tests of the processed composites demonstrated significant increases with an increasing volume fraction of the glass microspheres. In fracture toughness tests, KIC values higher than 12% were obtained. On the contrary, the immersion in water for 20 days promotes a decrease in flexural strength and flexural modulus greater than 11 and 22%, respectively. Finally, the influence of the addition of glass microspheres to the polyamide matrix was analyzed, and the increase in Tg with increasing fraction of the glass microspheres was observed.
- Roads as sources of heavy metals in urban areas. The Covões catchment experiment, Coimbra, PortugalPublication . Ferreira, António J. D.; Soares, Daniel; Serrano, Luis; Walsh, Rory P. D.; Dias-Ferreira, Celia; Ferreira, Carla S. S.Purpose This work studies the implications of different traffic patterns for heavy metal and solid pollution generation processes following rainfall events with contrasting antecedent meteorological conditions, at a periurban catchment. The aim is to provide information on the pollution processes and their potential environmental impacts for urban areas. Materials and methods Seven campaigns were performed covering winter, spring, and summer conditions, for rainfall events with different antecedent conditions. Four types of roads were monitored: low traffic, average traffic, heavy traffic with demanding driving situations (break and turning), and heavy traffic with high vehicle speed (motorway profile). Samples were taken at the beginning, middle and end of the events to measure within event variation in concentration. Analytical standard procedures were used to quantify pH, conductivity, turbidity, total solids, volatile solids, suspended solids, volatile suspended solids and heavy metals (Cd, Cu, Pb and Zn) in the total and dissolved forms (as to infer the particulate fraction), namely copper, zinc, cadmium and lead. Results and discussion The collected data show a direct relation among the number of vehicles and/or the driving manoeuvres performed by them and the amount of solids and heavy metals present in the wash out overland flow collected. An important fraction of the heavy metals is washed off in the particulate form, which represents an increased problem since the road overland flow is directed to green/brown areas and for the local aquatic ecosystems. Maximum copper values recorded exceed 0.6 mh L−1, zinc exceeds 5 mg L−1, lead 0.1 mg L−1 and cadmium 0.01 mg L−1. Values are higher after long dry spells and reduce concentration throughout the rainfall events. Conclusions An important part of the heavy metals (with relevance for zinc and lead) are washed off in the particulate form, pollutants are typically related to the amount of traffic, and especially to the existence of driving manoeuvres. The summer events show the highest values, due to the accumulation of pollutants during the long dry spells.
- High cytotoxicity and anti-proliferative activity of algae extracts on an in vitro model of human hepatocellular carcinomaPublication . Alves, Celso; Pinteus, Susete; Horta, André; Pedrosa, RuiBackground Cancer represents a serious threat for human health with high social and economic impacts worldwide. Therefore, the development of new anticancer drugs is of most importance. The aim of the present study was to evaluate the antitumor potential of twelve algae from Portugal coast on an in vitro model of human hepatocellular carcinoma (HepG-2 cells). Results Both extracts of Asparagopsis armata (1000 µg/ml; 24 h) presented high cytotoxicity with 11.22 ± 2.98 and 1.51 ± 0.38 % of HepG-2 live cells, respectively. Sphaerococcus coronopifolius methanolic and dichloromethane extracts (1000 µg/ml) also generated high reduction on HepG-2 viability (14.04 ± 2.62 and 12.84 ± 3.82 % of HepG-2 live cells, respectively). The most potent anti-proliferative activity was induced by dichloromethane extract (1000 µg/ml; 24 h) of Sphaerococcus coronopifolius, Asparagopsis armata and Plocamium cartilagineum with 99.61 ± 0.27, 98.56 ± 0.81 and 85.13 ± 1.04 % of cell’s proliferation reduction, respectively. Sphaerococcus coronopifolius dichloromethane extract exhibited the highest potency both on cytotoxicity and anti-proliferation assays with an IC50 of 14.1 and 32.3 μg/ml, respectively. Conclusions Sphaerococcus coronopifolius is a promising source of new molecules with possible application on cancer therapeutics.
- The many faces of a face: Comparing stills and videos of facial expressions in eight dimensions (SAVE database)Publication . Garrido, Margarida V.; Lopes, Diniz; Prada, Marília; Rodrigues, David; Jerónimo, Rita; Mourão, Rui P.This article presents subjective rating norms for a new set of Stills And Videos of facial Expressions—the SAVE database. Twenty nonprofessional models were filmed while posing in three different facial expressions (smile, neutral, and frown). After each pose, the models completed the PANAS questionnaire, and reported more positive affect after smiling and more negative affect after frowning. From the shooting material, stills and 5 s and 10 s videos were edited (total stimulus set = 180). A different sample of 120 participants evaluated the stimuli for attractiveness, arousal, clarity, genuineness, familiarity, intensity, valence, and similarity. Overall, facial expression had a main effect in all of the evaluated dimensions, with smiling models obtaining the highest ratings. Frowning expressions were perceived as being more arousing, clearer, and more intense, but also as more negative than neutral expressions. Stimulus presentation format only influenced the ratings of attractiveness, familiarity, genuineness, and intensity. The attractiveness and familiarity ratings increased with longer exposure times, whereas genuineness decreased. The ratings in the several dimensions were correlated. The subjective norms of facial stimuli presented in this article have potential applications to the work of researchers in several research domains. Fromour database, researchers may choose the most adequate stimulus presentation format for a particular experiment, select and manipulate the dimensions of interest, and control for the remaining dimensions. The full stimulus set and descriptive results (means, standard deviations, and confidence intervals) for each stimulus per dimension are provided as supplementary material.