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- Viver através da lente : um novo interface social ou a forma contemporânea de experienciar o real?Publication . Santos, David Rodrigues dosThis paper begins with the assertion, made by Jean Baudrillard, that the technologically mediated image has a strong predisposition to perversity. Starting with this approach, we have situated this analysis between the contact line of the artistic productions created with the aid of technology and the representations of the self through social networks. To this end, we have postulated three key concepts in which we highlight the role of the mediated image in artistic practices at the turn of the 20th century, in particular with the Fluxus movement. Secondly, we’ll discuss the underlying process of the informational aesthetics and the dialogical communication based on artworks created to operate in the communication and information network and, finally, we’ll conclude with a consideration of the importance that this interfaces grasp in shifting the way we experience the real.
- Reflexões em torno da reforma das prestações sociais – das pensões em especialPublication . Gonçalves, Luísa Andias
- Energy management in municipal solid waste treatment: A case study of a mechanical biological treatment facilityPublication . Bernardo, Hermano; Oliveira, Filipe Tadeu; Quintal, EdgarOver the last few years, mechanical biological treatment systems for municipal solid waste have been introduced in many European countries. In most cases, this was driven by the European Union Landfill Directive, which requires the diversion of biodegradable municipal waste from landfill to alternative processes. Although this type of treatment allows energy recovery from municipal solid waste, the process of mechanical biological treatment appears to be an intensive energy consumer, due to high demand of electricity consumed by process equipment. This paper presents the main results of an energy audit performed to a Mechanical Biological Treatment facility in Portugal, which due to the amount of energy consumed must comply with the Portuguese Program called Intensive Energy Consumption Management System – SGCIE. The program was created in 2008 to promote energy efficiency and energy consumption monitoring in intensive energy facilities (energy consumption higher than 500 toe per year). Facilities operators are required to perform energy audits and take actions to draw up an action plan for energy efficiency, establishing targets for energy consumption reduction and greenhouse gases emissions indexes. To implement actions that improve energy efficiency, it is necessary for the facilities operation to be associated with an effective energy management methodology, as well as an efficient facilities management procedure. The implementation of any energy management system should start with an energy audit, which was carried out to identify potential energy conservation measures for improving energy efficiency, and also typical energy consumption patterns and sector/equipment load profiles. This tool gives managers the information to support decision making on improving energy performance and reducing greenhouse gas emissions. Results shown that there is a considerable potential for reducing energy consumption and greenhouse gases emissions on Mechanical Biological Treatment units. Here, as elsewhere in the industrial sector, energy efficiency can only be achieved through a continuous energy monitoring and management system.
- 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.
- A methodology to evaluate the performance and consumption of vehicles in comparative on-road testsPublication . Ghodsirad, Mohammadhossein; Teixeira, Joao; Breda, Paulo; Campos, Cristina; Serrano, Luis; Silva, Manuel Gameiro daThe main objective of the reported work was to develop a methodology to assess the fuel consumption and the efficiency of the propulsion system of passenger cars equipped with internal combustion engines in road tests carried out to compare the performance of fuels with different formulations. The examination has been done out in highway travels. A Peugeot 407 HDI station wagon, with a 2,0 liter engine, has been equipped with different measurement systems. The measurement equipment is based upon two vehicle data loggers. A real-time fuel consumption metering system is combined with a GPS logger in order to analyze trip fuel consumption with different conditions in speed and altitude. An OBD II data logger is also mounted and the analog outputs of two pressure sensor are also connected to it. OBD II provides the vehicle and engine information available at the CPU unit, while the pressure sensors are connected to three pressure taps placed on the front of the vehicle to provide information about the relative velocity between the car and the air and the flow angularity. In the test, the impacts of speed, acceleration, road slope and wind disturbance on fuel consumption were analyzed for different fuel formulations. The developed system revealed to be well adapted to the requirements of the research project, allowing an accurate measurement of the fuel consumption and all the relevant parameters related to the vehicle movement. The best compromise in terms of sampling parameters has been achieved with a data acquisition frequency of 10 Hz, being the values decimated to 1 Hz, with the exception of the fuel consumption that is analyzed for 10 s integration intervals.
- Study of the driver’s behavior when cornering and characterization of safe speed perceptionPublication . Brás, M.; Ferreira, Carlos Daniel Henriques; Neves, CarlosRecently, there has been a growing interest in research towards autonomous vehicles, aiming to improve efficiency, safety, comfort and to eliminate human errors. However, a question arises: what should set the speed of the vehicle? The road legal limit, the maximum possible given the traffic conditions, the road critical speed or any other matter? Moreover, it has been mentioned in literature that drivers feel unsafe when using cruise control systems, namely in cornering conditions. Therefore, to study the driver’s behaviour when cornering, a test vehicle was equipped with a dedicated data acquisition system to acquire the vehicle dynamics and the driver heart rate. Trials with volunteers were carried out on a 22 km selected route, consisting of multiple types of roads, from city roads to highways. Based on the field results, we propose a control strategy for the vehicle speed when cornering relating the curve radius with the centrifugal acceleration. The proposed control strategy could be easily adopted by advanced driver assistance systems and autonomous vehicles. The reproduction of a human-like behavior will enhance the perception of safety and comfort of both the driver and occupants.
- Impact of trematodes on the population structure and shell shape of the estuarine mud snail Hydrobia ulvae from a Southern European estuary.pdfPublication . Bordalo, Maria D.; Ferreira, Susana M. F.; Jensen, Kurt T.; Pardal, Miguel A.The occurrence of trematodes within the gastropod Hydrobia ulvae was studied in two areas (a Zostera noltii bed and a eutrophic area) in the Mondego Estuary, Portugal. The aim was to assess trematode infections across snail age classes, as well as to investigate any influence of parasitism on the shell shape and size of these gastropods. In the Z. noltii bed, infection occurred in snails with shell height of 1.5-6 mm, but a higher prevalence was seen in intermediate size classes (3-5 mm). Infected individuals were never found among the elder gastropods. In the eutrophic area, infection was commonly observed within small individuals (1.6-2.5 mm), as large individuals were rarely found. The warm temperate climate in this coastal system may cause infected specimens to die before they can grow to larger dimensions, in contrast to Northern European populations. The frequency of snails with thin, distorted and corroded shells was higher among infected than non-infected snails. Infected individuals were frequently colonized by epibionts that may have additional detrimental effects and probably promote shell erosion. Infection with trematodes and their influence on snail size needs consideration in the evaluation of parameters related to population dynamics and population structure. If the implications of parasite infection are ignored, inadequate decisions about ecosystem management may be taken, resulting mainly from erroneous assessment of population structure, age composition and ecological longevity. The role of parasites is especially important to consider for systems under environmental stress.
- Database synchronization model for mobile devicesPublication . Domingos, João; Simões, Nuno; Pereira, Paulo; Silva, Catarina; Marcelino, LuisWith the increasing number of mobile devices it is necessary to create adapted solutions for this type of devices that respect their limited processing capacities, memory and bandwidth. We propose a synchronization model based on message digests to synchronize relational databases between mobile devices and a server, in order to minimize the data transferred between the device and the server and to minimize the processing done by the mobile device. The approach consists in a synchronization model where the amount of data to be exchanged has been reduced to the minimum. In order to achieve the model above a registry is done in the device with the new, the modified or removed content, which purpose is to send only the essential data for synchronization from the device to the server. Regarding the synchronization from the server to the device, the modifications are calculated and sent to the device. This model is independent of proprietary solutions and can be adapted to any system or platform, often involving software development to the mobile application and the application server. The results of testing the model show that the proposed model can achieve better synchronization times than the competitor models, while always fulfilling the set objectives.
- Decision Support System to Diagnosis and Classification of Epilepsy in ChildrenPublication . Rijo, Rui; Silva, Catarina; Pereira, Luis; Gonçalves, Dulce; Agostinho, MargaridaClinical decision support systems play an important role in organizations. They have a tight relation with the information systems. Our goal is to develop a system to support the diagnosis and the classification of epilepsy in children. Around 50 million people in the world have epilepsy. Epilepsy diagnosis can be an extremely complex process, demanding considerable time and effort from physicians and healthcare infrastructures. Exams such as electroencephalograms and magnetic resonances are often used to create a more accurate diagnosis in a short amount of time. After the diagnosis process, physicians classify epilepsy according to the International Classification of Diseases, ninth revision (ICD-9). Physicians need to classify each specific type of epilepsy based on different data, e.g., types of seizures, events and exams' results. The classification process is time consuming and, in some cases, demands for complementary exams. This work presents a text mining approach to support medical decisions relating to epilepsy diagnosis and ICD-9-based classification in children. We put forward a text mining approach using electronically processed medical records, and apply the K-Nearest Neighbor technique as a white-box multiclass classifier approach to classify each instance, mapping it to the corresponding ICD-9-based standard code. Results on real medical records suggest that the proposed framework shows good performance and clear interpretations, albeit the reduced volume of available training data. To overcome this hurdle, in this work we also propose and explore ways of expanding the dataset.
- Enterprise Information SystemsPublication . Varajão, João; Martinho, Ricardo; Soto-Acosta, PedroThis special issue includes original, pertinent and relevant contributions on the technological, organizational and social dimensions of the largely multidisciplinary field of Enterprise Information Systems.