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- A gyro-enhanced smart-phone framework to develop motion-based user interfaces for animation and virtual environmentsPublication . Pereira, Tiago; Pereira, Orlando; Fazendeiro, Paulo; Gomes, AbelIn this paper, the mobile phone is presented as an alternative device to interact with animation systems and virtual environments, including video games. Basically, we show how the gyroscope of a mobile device can work as a sensor to control the pose and motion of a mobile device controlled object or character in a 3D virtual world. More specifically, we introduce a framework that enables the development and rapid prototyping of motion-based user interfaces for animation systems and virtual environments. This framework provides tools to capture and control the motion of mobile devices-binded objects in a 3D virtual scene over a wireless communication channel via a simple, fast and efficient protocol named Open Sound Control (OSC).
- Anonymized Data Assessment via Analysis of Variance: An Application to Higher Education EvaluationPublication . Ferrão, Maria Eugénia; Prata, Paula; Fazendeiro, PauloThe assessment of the utility of an anonymized data set can be operational-ized by the determination of the amount of information loss. To investigate the possible degradation of the relationship between variables after anony-mization, hence measuring the loss, we perform an a posteriori analysis of variance. Several anonymized scenarios are compared with the original data. Differential privacy is applied as data anonymization process. We assess data utility based on the agreement between the original data structure and the anonymized structures. Data quality and utility are quantified by standard metrics, characteristics of the groups obtained. In addition, we use analysis of variance to show how estimates change. For illustration, we apply this ap-proach to Brazilian Higher Education data with focus on the main effects of interaction terms involving gender differentiation. The findings indicate that blindly using anonymized data for scientific purposes could potentially un-dermine the validity of the conclusions.
- Societal risks of the end of physical cashPublication . Almeida, Pedro De; Fazendeiro, Paulo; Inácio, Pedro R. M.Cash, standardized physical tokens that represent economic value, has been a key instrument in the evolution of human civilizations for around 3000 years. However in the last few decades cash has been progressively losing its preeminence in favour of electronic handling of money transactions. The shift to a cashless society, in which physical money is completely or almost completely replaced by electronic records is on the horizon. Regardless of its advantages and disadvantages, electronic handling of money needs the support of a complex technological infrastructure which operation depends on many factors. This paper discusses this subject in detail, identifies the main threats linked to electronic money handling and evaluates their possible impacts on societies that no longer rely on cash.
- Applications of artificial immune systems to computer security: A surveyPublication . Fernandes, Diogo A. B.; Freire, Mario; Fazendeiro, Paulo; Inácio, Pedro R. M.For the last two decades, artificial immune systems have been studied in various fields of knowledge. They were shown to be particularly effective tools at detecting anomalous behavior in the security domain of computer systems. This article introduces the principles of artificial immune systems and surveys several works applying such systems to computer security problems. The works herein discussed are summarized and open issues are pointed out afterwards, elaborating on a novel applicability of these systems to cloud computing environments.
- SoTRAACE: Socio-technical risk-adaptable access control modelPublication . Moura, Pedro; Fazendeiro, Paulo; Marques, Pedro; Ferreira, AnaWithin the necessary security requirements, accesRisk Adaptable Accesss control measures are essential to provide adequate means to protect data from unauthorized accesses. However, current and traditional solutions are commonly based on predefined access policies and roles and are therefore inflexible by assuming uniform access control decisions through people’s different type of devices, environments and situational conditions, across enterprises, location and time. The most ubiquitous device that people now hold is the smartphone. We live in an age of the mobile paradigm of anytime/anywhere access from different types of connections and situations to different types of information. In this new age, access control models need to determine adaptable access decisions based on multiple factors aggregated at the moment of the request, to calculate the security risk and operational security needs, and not just to perform a predefined comparison of attributes. Thus, there is a need for more innovative, flexible, adaptive, dynamic, transparent and more resilient access control models, that are required for more heterogeneous requests. This paper presents a new dynamic access control model: SoTRAACE - Socio-Technical Risk-Adaptable Access Control Model. The model aggregates attributes from various domains to help performing a risk assessment at the moment of request. The risk assessment is balanced against the operational needs to provide the most accurate and secure access decision. As a proof of concept SoTRAACE is used to model and compare two different use-case scenarios in the healthcare sector.
- A Cellular Automata Model of Spatio-Temporal Distribution of SpeciesPublication . Bioco, João; Silva, João; Canovas, Fernando; Fazendeiro, PauloCellular automata (CA) are discrete models frequently used in ecological and epidemiological studies due to the capacity to simulate dynamics systems and analyze their behavior. One of the applications of CA in ecology is in the analysis of the spatial distribution of species, where models are created and simulated in order to study the response of ecological systems to different kinds of exogenous or endogenous perturbations. In this study we describe an implementation of a cellular automaton model able to incorporate environmental data collected from different heterogeneous sources. To the user is given the power to produce and analyze different scenarios by combining the available variables at will. Different hypothesis regarding the individual contribution of each environmental variable can be promptly tested. As an illustrative example of the flexibility of our implementation we present a case study where, departing from a general additive model (GAM), validated in the literature, a possible explanation is given for the spatio-temporal distribution of two haplotypes of honeybees along Iberian Peninsula. Environmental data were used to describe every 30x30 second unit grid of the study area (World Geodetic System 1984 WGS84, geographical coordinates). The results of our model are compared and discussed at the light of the real data collected on the terrain. Curiously enough, both in the synthesized model and in the real data, one can observe that the frequency of African haplotypes decreases in a SW-NE trend, while that of west European lineage increases.
- Performance Assessment of the Canonical Genetic Algorithm: a Study on Parallel Processing Via GPU ArchitecturePublication . Fazendeiro, Paulo; Prata, PaulaGenetic Algorithms (GAs) exhibit a well-balanced operation, combining exploration with exploitation. This balance, which has a strong impact on the quality of the solutions, depends on the right choice of the genetic operators and on the size of the population. The results reported in the present work shows that the GPU architecture is an efficient alternative to implement population-based search methods. In the case of heavy workloads the speedup gains are quite impressive. The reported experiments also show that the two-dimensional granularity offered by the GPU architecture is advantageous for the operators presenting functional and data independence at the population+genotype level.
- Towards Forest Fire Prevention and Combat Through Citizen SciencePublication . Bioco, João; Fazendeiro, PauloInvolving the community (volunteers) in citizen science projects is a good way to address and prevent a lot of societal concerns. The participation of volunteers has been quit frequent in citizen science projects; making them a fundamental key for the success of these projects. Volunteers participate in citizen science projects by collecting and processing data that can be used for various purposes such as educational, scientific, preservation of biodiversity, decision-making, etc. In forest fire prevention, participation of citizens in collecting and processing data could help significantly in decision-making related to forest fire prevention and mitigation. Mobile phones can be the tool of choice for collecting data due to not only to its wide availability and powerful communication features but also to its embedded sensing capabilities such as GPS location, camera and microphone. This study is concerning to the development of a mobile-based citizen science project that allows volunteers to report fire-prone area, the occurrence of fire, and area where fire has occurred; then these information are used by firefighters and specialists for decision-making. In a scenario of fire occurrence, volunteers can take a picture of the place where the fire is occurring, upload to the mobile application, and send GPS location of the place; then the application notifies the firefighters and helps them allocate the needed resources to combat the fire based on the information sent by the volunteers.
- Parameterization of an Agent-Based Model of Spatial Distribution of SpeciesPublication . Bioco, João; Fazendeiro, Paulo; Canovas, Fernando; Prata, PaulaAgent-based models (ABMs) have been widely applied in several fields such as ecology, biology, climate changes, engineering and many other fields. In ABMs approach, the behaviour of a system is determined by the local interactions between its individuals (agents), and the interactions between these individuals with the environment where they exist. Due to its interactions at the individual’s level, ABMs can produce quite realistic results regarding to the models behaviour. Therefore it is necessary to perform several analysis from the point of view of the models parametrization. In this paper we perform a parametric study in ways to analyze the implications of models parameterization in the models output, by implementing an agent-based model to simulate spatial distribution of species in an heterogeneous environment. The models output resulting from several parameters combination are compared and discussed.
- Smart Helmet: An Experimental Helmet Security Add-OnPublication . Sales, David; Prata, Paula; Fazendeiro, PauloWhen it comes to ride a motorcycle the drivers-centered road safety is quintessential; every year a remarkable number of accidents directly related to sleepiness and fatigue occur. With the objective of maximizing the security on a motorcycle, the reported system aims to prevent sleepiness related accidents and to attenuate the effects of a crash. The system was developed as the less intrusive as it could be, with sensors that allow the capture of reaction times to stimuli-response and collect acceleration values. To obviate the lack of data related to sleepiness during motorcycle riding, a machine learning system was developed, based on Artificial Immune Systems. This way, resourcing to a minimum amount of user input, a custom system is synthesized for each user, allowing to assess the sleepiness level of each subject differently.