PRIVED: a Privacy Model for Heterogeneous Mobile Networks

We propose a network-oriented privacy model (PRIVED) composed by a well defined information model, using events, information sets and relationships to define the conceptual privacy relationships that can occur in the network. We propose formal rules and a network instantiation, using linkability and correlation as the main tools for network applicability. We also use the model to determine the best approaches towards privacy protection in the network, resulting in a vertical/horizontal network privacy dichotomy

The Exact Value for European Options on a Stock Paying a Discrete Dividend

In the context of a Black-Scholes economy and with a no-arbitrage argument, we derive arbitrarily accurate lower and upper bounds for the value of European options on a stock paying a discrete dividend. Setting the option price error below the smallest monetary unity, both bounds coincide, and we obtain the exact value of the option.Comment: 14 pages,3 figure

The exact value for European options on a stock paying a discrete dividend

In the context of a Black-Scholes economy and with a no-arbitrage argument, we derive arbitrarily accurate lower and upper bounds for the value of European options on a stock paying a discrete dividend. Setting the option price error below the smallest monetary unity, both bounds coincide, and we obtain the exact value of the option.European options; Black-Scholes economy

Política e segurança : desafios aos fundamentos do estado democrático e visões globais da segurança para o século XXI

O tema da Segurança, primeiro fim do Estado, é indissociável da democracia e da liberdade, e é crucial na medida em que se trata de um desígnio dos homens (que amam a liberdade) e remete para o cuidado com a própria conservação do Estado, assim como com o bem-estar dos seus cidadãos e bens, independentemente do país e da conjuntura em que vivam. É ainda o desejo de sair daquela mísera condição de guerra que é a consequência necessária das paixões naturais dos homens, quando não há um poder visível capaz de os manter em respeito, forçando-os, por medo do castigo, ao cumprimento dos seus pactos e ao respeito àquelas leis, como ensinara Thomas Hobbes, no seu magistral Leviatã. Por conseguinte, o Estado tem a obrigação de regular a relação política com os diversos modos de entender a incerteza, o risco e a conflitualidade e, no limite, a própria violência no seio da polis, limitadora da própria liberdade, fundamento do rule of law. É esta íntima relação circular entre segurança, democracia e liberdade nas democracias liberais que impõe uma tal pressão sobre o aparelho de Estado, mormente nos organismos que têm por função e competência a segurança do Estado (nas suas vertentes interna e externa), que o obriga a reconhecer a impotência da sua tradicional supremacia.Apoio da FC

A solution to prevent and minimize the consequences of accidents with farm tractors in the context of mountainous regions with low population density

Farm tractors have become a key part of daily routine agriculture, converting complex and time-consuming tasks into tasks that are easier to perform and less dependent on human labor, contributing directly to increasing the economic value generated by this activity sector, either by increasing the productivity or by making certain agricultural crops viable, which otherwise would not be sustainable. However, despite all the advantages, accidents with this type of equipment are common, often with critical and sometimes fatal consequences. The evolution of safety requirements of these machines has occurred at a good level; however, a significant part of the agricultural tractors in use are older models that do not have such solutions. Even in the new models, which contain such solutions, these are not always correctly used, and it is even common that they are turned off or simply not used at all. It is therefore natural that accidents continue to occur, a situation that is aggravated by other factors. Lack of situational awareness of the operators, which can result from advanced age, inadequate training, reduced sensitivity/respect for safety rules, or working on irregular terrain like mountainous areas, contribute to high-risk contexts that end in the loss of human life. The consequences of such accidents are clearly aggravated by the time it takes to assist the victims—either because accidents are simply not identified/reported immediately, or by the time it takes to locate and provide help to the victims. This is a scenario that is more common in mountainous regions and regions with low population density. The current paper, using NB-IoT, a set of sensors, and a web application, presents a conceptual toolset conceived to prevent accidents and minimize consequences (human and material) that can be applied to old and new farm tractors. The development was carried out taking the characterization of the farmers and the land in the region in which the authors’ research institution is located into account, which has the highest rate of fatal accidents with agricultural tractors in the country; it is a region of mountainous with a very low population density.Polytechnic Institute of Bragança for financial support through funds from POCH-02-53I2- FSE-000004, project TRACE IPB: Knowledge Transfer and Employability IPB. Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI (UIDB/05757/2020 and UIDP/05757/2020) and SusTEC (LA/P/0007/2021).info:eu-repo/semantics/publishedVersio

Relation between musculoskeletal pain and postural habits in female students of elementary school

info:eu-repo/semantics/publishedVersio

Reducing go-around attempts based on history of successful landings for aviation in general

Nowadays, flying is a fundamental part of society. Traveling is increasingly accessible, which supports not only the aeronautical industry but also the tourism sector in some regions around the world. However, despite its importance in society in general, where there are more and more airplanes in the air, the aviation industry has also become one of the primary sources of pollution, and when considering entertainment aviation, the problem becomes even more complicated. In recent years, all aeronautical manufacturers have been working on solutions that reduce the sector’s impact on climate change. Landings are of particular importance in the fuel consumption aspect, especially if it is taken into account that for various reasons a pilot may decide to abort the maneuver, meaning a few more kilos of fuel that will be consumed consequently making more pollution. The present work suggests an architecture based on the history of successful landings providing the pilot suggestions to reduce the probability of a go-around.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI (UIDB/05757/2020 and UIDP/05757/2020) and SusTEC (LA/P/0007/2021).info:eu-repo/semantics/publishedVersio

Design de produto e corpo humano : ligações objecto-corpo na contemporaneidade.

Dissertação para a obtenção do grau de Doutor em Design, apresentada na Universidade de Lisboa - Faculdade de Arquitetura