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- Security Monitoring in a Low Cost Smart Home for the ElderlyPublication . Ferreira, Gabriel; Penicheiro, Paulo; Bernardo, Ruben; Neves, Álvaro; Mendes, Luís; Barroso, João; Pereira, AntónioThe general increase in life expectancy and the consequent ageing of the general population impose major challenges to modern societies. Most elderly people experience the typical problems related to old age, such as chronic health problems, as well as sensory and cognitive impairments. In addition, in today’s modern societies, where families have less and less time to look after their older relatives, the isolation of the elderly is a real concern and a highly recurrent problem, which is enhanced when they live alone. To solve, or at least minimize, these problems, a smart home monitoring system was developed, as presented and described in this paper. This solution is implemented based on a sensory network which detects anomalous behaviors, immediately triggering a warning to the caregiver or family. A strong concern when developing a project of this kind is the physical security of the elderly. Houses tend to have hazardous objects and characteristics that may inflict serious injuries to their occupants or, in extrema, even death. As time goes by, the elderly start losing muscle mass and osteoporosis may appear, as well as vision and hearing impairments, which increase the likelihood of falling. Several other serious accidents may also occur, such as gas leaks, floods and fire outbreaks. Therefore, this population would strongly benefit from a solution which helps predict and even prevent accidents before they happen.
- Low-Cost Smart Surveillance System for Smart CitiesPublication . Brás Pereira, Rúben Filipe; Correia, Diogo; Mendes, Luís; Rabadão, Carlos; Barroso, João; Pereira, AntónioThe safety of people and spaces is of paramount importance for societies. With time, the implementation of safety measures is rapidly changing from a need to a priority. Video surveillance systems play a key role in the surveillance of crucial and critical areas as these systems help the authorities keep places safer. With the rapid growth of technology and the implementation of the smart city concept, it is becoming possible to develop and deploy wide area surveillance systems. The ease with which these systems can be installed in private and public spaces (e.g., homes, streets and parks) allow for the creation of ubiquitous monitored environments. Rapid intervention responses to any abnormal situation or the use of recorded video as evidence are some advantages of the use of this type of surveillance systems. Although ubiquitous video surveillance systems are relevant for present modern societies, their cost is still high. To solve or, at least to mitigate this problem, a low-cost smart surveillance system was developed, which is presented and described in this paper. The developed surveillance system, based on available low-cost technology, can help keep critical spaces under surveillance 24/7. The proposed solution was found to have a minimal cost, a low bandwidth, and to be scalable and adaptable to every client’s needs. Thus, the solution can be used by anybody (private and public) and applied in different contexts (e.g., residential, industrial). The system can provide still images, captured from surveillance video cameras, real time video and real time video processing, which can be used for motion detection. When this happens, the user is warned via an e-mail containing the identification of the respective surveillance camera. Only the relevant video events are sent, recorded and maintained in the cloud platform system, consequently reducing the amount of storage space required to maintain all the historical video events. The results of the tests carried out show that it is possible to stream a video from the surveillance cameras with an insignificant delay and that motion detection can be attained through real time video processing. The system presented potentiates a low-cost solution for a smart city in the surveillance field.
- JavaScript Middleware for Mobile Agents Support on Desktop and Mobile PlatformsPublication . Silva, Carlos; Costa, Nuno; Grilo, Carlos; Veloz, JorgeThe evolution of technology in interconnection solutions such as Networks or the Internet, have allowed many communication architectures to be born and a varied interconnectivity. Here, we present a project that relies on the mobile agent computing paradigm. A middleware using the JavaScript language that allows the execution and ability to move mobile agents through the local network and Internet. This initiative arose as a way of dealing with problems raised by the considerable amount of existing Java based mobile agents middleware, which force the installation of the Java Virtual Machine in the devices, making complicated its execution in operating systems like macOS, iOS and others non-java friendly O.S. Our middleware works steadily in all operating systems, requiring only the installation of node.js. For mobile platforms the middleware is developed using React-native that allows it to run on mobile operating systems such as Android and iOS.
- Optimizing GPU Code for CPU Execution Using OpenCL and Vectorization: A Case Study on Image CodingPublication . Pereira, Pedro M. M.; Domingues, Patrício; M. M. Rodrigues, Nuno; Gabriel Falcao; Faria, Sergio M. M. deAlthough OpenCL aims to achieve portability at the code level, di erent hardware platforms requires di erent approaches in order to extract the best performance for OpenCL-based code. In this work, we use an image encoder originally tuned for OpenCL on GPU (OpenCL-GPU), and optimize it for multi-CPU based platforms. We produce two OpenCL-based versions: i) a regular one (OpenCL-CPU) and ii) a CPU vector-based one (OpenCL-CPU-Vect). The use of CPU vectorization exploits the OpenCL support, making it much simpler than directly coding with SIMD instructions such as SSE and AVX. Globally, while the OpenCL-GPU version is the fastest when run on a high end GPU requiring around 580 seconds to encode the Lenna image, its performance drops roughly 65% when run unchanged on a multicore CPU machine. For the CPU tuned versions, OpenCL-CPU encodes the Lenna image in 805 seconds, while the vectorization-based approach executes the same operation in 672 seconds. Results show that meaningful performance gains can be achieved by tailoring the OpenCL code to the CPU, and that the use of CPU vectorization instructions through OpenCL is both rather simple and performance rewarding.
- Local Seismic Cultures: The Use of Timber Frame Structures in the South of PortugalPublication . Ortega, Javier; Vasconcelos, Graça; Rodrigues, Hugo; Correia, MarianaLocal Seismic Cultures and traditional earthquake resistant constructions and techniques arise in seismic prone regions as a reaction to earthquakes. People continuously exposed to seismic hazard eventually had to learn how to protect themselves and developed preventive measures for earthquake mitigation. These construction efforts made by local populations gave rise to the development of what was defined by Ferrigni [1] as Local Seismic Culture. In Portugal, there is a particular well-known and widely studied type of timber frame construction that can be highlighted as the most representative example of Portuguese Seismic Culture: the Pombalino construction system [2,3]. This system was devised by the government and its use for the complex reconstruction process carried out in Lisbon after the 1755 earthquake was mandatory. It can be considered as the first technical regulation regarding seismic resistance. Furthermore, local communities adopted this constructive system as a model of earthquake resistant construction and its use widely spread around the country, eventually becoming endemic of the vernacular way of building of the country. Given the fact that using timber frame structures has proven to improve the seismic behavior of vernacular architecture, as has been reported in past earthquakes in many countries [4-7], its preservation as a traditional earthquake resistant practice is important. This paper firstly intends to evaluate whether the use of timber frames as a traditional seismic resistant technique for vernacular architecture in the South of Portugal, traditionally a seismic region, is still active. Secondly, the city of Vila Real de Santo António was selected as a case study because it also followed a Pombaline development contemporary to the reconstruction of Lisbon. The plan included the provision of timber frame partition walls for some of the buildings and, thus, an overview of the type of constructions originally conceived is provided. Finally, the alterations done in the original constructions and the current state of the city center are described and the effect of these changes on the seismic vulnerability of the city is discussed.
- Seismic vulnerability of vernacular buildings in urban centres-the case of vila real de santo antónioPublication . Vasconcelos, G.; Lourenço, P.B.; Rodrigues, H.; Varum, H.Following detailed studies of Portuguese vernacular building typologies, this paper deals with buildings located in historical urban centres. An analysis of the history of the urban centre and, in particular, of some vernacular buildings is enhanced. Additionally, a discussion on the influence of changes of the geometry, and on added built volumes to original buildings in the seismic vulnerability of the buildings is also provided.
- Sustainable Impact Evaluation of Support Structures in the Production of Extrusion-Based PartsPublication . Henrique A. Almeida; Correia, Mário S.Sustainability creates and maintains the conditions under which humans and nature can exist in a productive harmony, fulfilling the social, economic and other requirements of present and future generations. Environmental and social concerns about human society’s impact on the natural environment have been pushing sustainable development issues. Sustainable industrial practices can contribute to the development of more sustainable materials, products, and processes. It is critical to apply eco-design principles and develop greener products and production processes, reducing impacts associated with production and consumption. Bearing this in mind, additive manufacturing has the capability of producing components with the lowest amount of raw material. Alongside with the raw material, in some additive manufacturing systems, support material is needed in order to undergo the production. This present work aims to evaluate the environmental impact of the support production methodologies in order to deliver awareness to the users of extrusion-based systems for a lower environmental impact assessment. The extra production time involved in the production of the support structures and the support structure removal is evaluated. The evaluation consisted of correlating the volume of support material and the time needed for its dissolution. Two different models were then compared with different support material production schemes, regarding the total energy consumption and its environmental impact. The results demonstrate that different support production schemes have significant environmental impact regarding both production and its dissolution.
- Sustainability Based on Biomimetic Design ModelsPublication . Henrique A. Almeida; Oliveira, Eunice S. G.Ecodesign is an approach to designing products with special consideration for the environmental impacts of the product’s life cycle. In a lifecycle assessment, the life cycle of a product is usually divided into procurement, manufacture, use, and disposal. Ecodesign is a growing responsibility and understanding of our ecological footprint on the planet. It is imperative to search for new productive solutions that are environmentally friendly and lead to a reduction in the consumption of materials and energy while maintaining the desired performance of the products. Bearing this in mind, additive manufacturing has the capability of producing components with the lowest amount of raw material needed and the highest geometrical complexity. This work aims to present novel bioinspired design methodologies for the production of additive manufacturing products with lower amounts of material and higher performance. The bioinspired design considers natural cellular-based concepts for the definition of novel product definitions.
- Seismic Retrofitting: Learning from Vernacular ArchitecturePublication . Costa, A.; Varum, H.; Pinheiro Rodrigues, Hugo Filipe; Lourenço, P.B.; Vasconcelos, G.; Mariana R. Correia; Paulo B. Lourenço; Humberto VarumRammed earth is one of the oldest building materials in the world, and it is present in Portugal with a particular focus in the South of the country. The mechanical properties and the structural behaviour of rammed earth constructions have been the subject of study of many researchers in the recent years. This study is part of a broader research on vernacular seismic culture in Portugal. Numerical analyses were carried out to assess the influence of different retrofitting solutions in the behaviour and seismic performance of a rammed earth building, representative of the vernacular heritage of Alentejo region. Understating the structural fragilities of this type of constructions allowed determining the most appropriate retrofitting solutions.
- Seismic behaviour assessment of vernacular isolated buildingsPublication . Ortega, J; Vasconcelos, G; Lourenço, P; Pinheiro Rodrigues, Hugo Filipe; Varum, H.This paper presents the numerical seismic analysis of isolated vernacular buildings characteristic of the Alentejo region, which is considered a medium seismic hazard region in Portugal.A representative isolated building was selected from a database, and a geometric model was defined for the numerical pushover analysis. Subsequently, a parametric analysis was carried out to assess the influence of distinct parameters on the seismic behaviour of such buildings.