CIIC - Publicações em Atas de Conferências com Peer Review
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- Towards the automatic selection of moving regions representation methodsPublication . Costa, Rogério Luís C.; Miranda, Enrico; Moreira, JoséMoving region is an abstraction used to represent the spatio-temporal behavior of real-world phenomena in database systems. The most common approach to model moving regions uses geometries to represent their position and shape at different times (observations), and interpolation functions to generate the evolution of the geometries between observations. Several region interpolation methods have been proposed in the databases literature, but as there is no suitable method for all use cases, users must select the most adequate algorithm to represent each region by visual inspection. This can be infeasible when dealing with large datasets. This paper presents the first steps towards a system that suggests which methods (and configurations) can generate representations fitting the requirements of a particular application. It includes an abstract specification of user-defined rules on the spatio-temporal evolution of moving regions to assess the suitability of region interpolation functions, a discussion on optimization strategies for efficient implementation of the rules and illustrative examples using real-world data to show how to use this approach to select the best methods to represent a spatio-temporal phenomena.
- Dispositivo de Navegación Portable para Personas No VidentesPublication . Yanez, Daniel Vera; Marcillo, Diego; Pereira, AntónioLa visión es uno de los más importantes sentidos que ayuda a las personas a navegar en nuestro mundo. Comúnmente las personas no videntes desarrollan sus otros sentidos para poder sentir sus alrededores, pero en ciertos casos esto no es suficiente. Los sentidos pueden ser perturbados por el ruido o enfermedades. Por esta razón se han desarrollado muchos artefactos para ayudar a este grupo de personas. Artefactos como bastones blancos o perros guía ayudan a las personas no videntes a moverse en su entorno. Este artículo propone el uso de un sistema que detecta y reconoce obstáculos cercanos, dando una retroalimentación audible al usuario, evitando una colisión. Es un sistema inalámbrico para que sea cómodo para el usuario. El sistema ayuda a las personas con discapacidad visual a moverse en escenarios interiores o exteriores. Los objetivos del sistema es detectar los obstáculos que los bastones blancos o los perros guía no pueden, ampliando su rango de detección.
- System Protection Agent Against Unauthorized Activities via USB DevicesPublication . Oliveira, José; Frade, Miguel; Pinto, PedroSecurity attacks using USB interfaces and devices are becoming more advanced, which boost efforts to develop counter measures in order to protect systems and data. One of the most recent attacks using USB devices is the BadUSB attack, performed by spoofing the device’s firmware and allowing the attackers to execute a set of malicious actions, e.g. an USB storage device could be mounted as USB keyboard in order to inject malicious scripts into the system. This paper proposes a protection agent against BadUSB attack developed for Windows operative systems. It allows a user to check the class of an USB device ready to be mounted, though enabling the detection of a potential attack if the expected functionality of the device does not match with its class type. The results show that the proposed protection agent is capable of detecting potential intrusions by blocking the installation of the device, scanning the device for something that identifies it, searching for a description locally and finally warning the user about the device meaning that all devices must be approved by the user when plugged in if the system protection agent is running.
- Fighting Elders’ Social and Technological Exclusion: The TV Based ApproachPublication . Correia, Luís; Costa, Nuno; Pereira, AntónioWe are assisting to the fastest grow of senior population ever and that tendency has brought several challenges for governments, families and for the elderly. The society was not prepared for that. On the one hand, there are many elderly who live alone in the cities and, on the other hand, active people is moving to the cities looking for a better life while leaving behind the villages where they born and grow and the older family members. On the other side, everyone is expecting the aid of technology in order to solve or at least minimize this problem. This paper present a video-calling service targeted for elderly social and technological exclusion and promoting socialization while using recent technology embedded into well-known electronic devices like TVs. The evaluation of results showed that when assisted technology is encapsulated into everyday objects, older people can use it seamlessly, without any learning curve.
- Kinect sensor performance for Windows V2 through graphical processingPublication . Vargas, Javier; Mariño, Christian; Aldas, Clay; Morales, Luis; Toasa, RenatoThe present paper describes a study based on the loss and gain of frames that are obtained through sensors (color, depth, and body tracking) of Kinect V2. For this purpose, it is established a time to obtain each frames per second (FPS), evaluating a performance of sensors in three evaluation instances, using native Kinect V2 libraries and other graphic processing libraries. In addition, several experimental tests were carried out, in order to verify the best performance of a test application based on graphical processing of each sensor.
- Digitally Signed and Permission Restricted PDF FilesPublication . Domingues, Patrício; Frade, MiguelThe PDF format is the de-facto standard for many types of documents. Often a forensic digital investigation is faced with a significant volume of PDF files. It is thus important to filter PDF files, giving priority to files that have an high probability to carry important and meaningful data. In this paper, we focus on identifying potential important PDF files, selecting i) digitally signed files and ii) files that have special owner restrictions set, such as interdiction to assemble/separate pages. For this purpose, we present the python-based digiSign|protectedPDF module for the open source Autopsy forensic software. When run over a digital forensic data source, the module creates two lists: one holding the digitally signed files and, another one with files that have special restrictions in their usage. To study the occurrence of digitally signed and of permission-protected PDF and their importance for digital forensics, we analyzed a Windows 10 forensic image, finding that 2.81% of the PDF files were digitally signed and 3.75% were permission-protected. The study shows that digitally signed PDF files can harbor meaningful data for a digital forensic investigation.
- Y.S.Y.D. - You Stay You Demand: User-centered design approach for mobile hospitality applicationPublication . Esteves, Micaela; Pereira, AngelaThe evolution and widespread use of mobile technologies has boosted the hotel industry to develop applications for these devices. Several tourism applications and services for mobile devices have been developed in recent times. However, many of these services are not oriented for hotel guest, rather than these services are more focused on delivering information instead of targeting the specific needs of guests. Based on a study carried out in Portugal by the researchers, were found that the most mobile hotel applications and websites are focused on dreaming, planning and booking stages rather than in experiencing and sharing. Some of these mobile applications are reproduction of websites, which do not bring added value to the guests during their stay. Thus, it was developed the mobile hotel application, You Stay You Demand (Y.S.Y.D.), with a User-Centered Design approach that makes easier the communication between guests and hotel staff for guest satisfaction. During the study were integrated the Nielsen's heuristic evaluation with user testing to assess the usability which created a user-centered interface.
- 802.21-MPA-IMS ArchitecturePublication . Rodrigues, Carlos Miguel de Jesus; Rabadão, Carlos; Pereira, AntónioMobility has become a keyword nowadays with the evolution of mobile devices market and proliferation of realtime services. IP Multimedia Subsystem (IMS) is a single, standardized service framework that supports voice, video, data and messaging services, but does not provide seamless mobility for packet based sessions. This paper purposes an IMS architecture with IEEE 802.21 and media-independent pre-authentication (MPA) integrated. IEEE 802.21 can enable this seamless mobility in IMS and, additionally, MPA provides a secure handover optimization scheme, reducing, as a consequence, handover latency. The main goal of this architecture is to provide seamless and secure handovers between different access technologies in an IMS-based environment.
- Wireless Networks Interoperability - Wifi Wimax HandoverPublication . Silva, Hugues Mickael Carreira da; Figueiredo, Luís Filipe Calado Carvalho de; Rabadão, Carlos; Pereira, AntónioThe mobility with quality of service in wireless networks is a reality ever closer. The need for mobility while communicating becomes more and more necessary. Technologies for wireless networks with interoperability develops the concept of "communications anytime anywhere". Interoperability uses the handover to ensure the mobility of a mobile terminal through various communication infrastructures, supported by different technologies of wireless networks. Maintain the connection between base stations and mobile terminal is the key of the customer's satisfaction, with the guarantee of continuity of services and applications running, moving between different cells, using the technology of wireless communications to provide better coverage in the position where is. The aim of this study is to examine how the mobility between different access technologies in wireless networks can be optimized and what their behavior in scenarios of interoperability. To examine the quality of the service of mobility, we analyze the time required for the handover and the existing loss of packages, the latter being a very important factor to satisfy the user.
- Energy systems models for efficiency towards Smart CitiesPublication . Galvao, Joao R.; Moreira, Licinio M.; Teixeira Ascenso, Rita Margarida; Leitao, Sergio A.The way of energy use in the European Union (EU) needs to be improved by continuous promotion of sustainability and an efficient manner to ensure citizens' quality of life. This work presents two new energy models: i) retrofit of the present energy system in a public library building; ii) improving energy efficiency in public lighting using new technological solution Light Emission Diode (LED), new methods of control and management while leveraging the use of renewable energy as power supply. Both can act as a vehicle to disseminate concepts of Smart City (SC) and Internet of Things (IoT), also, as the development of energy production based on renewable energies: biomass and sunlight. With these two proposals it is intended to improve energy efficiency behaviours reducing energy waste, making use of the latest techniques and equipment, which promote more efficient management. This will lead to an effective reduction of energy consumption associated with public lighting while maintaining recommended levels of luminance in different situations. Finally this research is also to complete, a long-term goal of the EU, which is to develop a society that better uses their energy systems and, in Portugal, increase the use of available renewable energy sources.
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