On the feasibility of using 5G enabled smartphones to improve safety of vulnerable road users

Autonomous vehicles require sophisticated sensors to safely and timely detect the conditions of the world around them and act accordingly. However, just like human senses, sensors have limitations and blind spots. Vulnerable Road Users, such as pedestrians and cyclists, are at particular risk since they can quickly come to the road from a blind spot too late for the vehicle to react. This article evaluates the use of a commercial 5G-enabled smartphone and a purpose-designed app to advertise a Vulnerable Road User position to a connected autonomous vehicle using European Telecommunications Standards Institute standard messages. The results obtained in a real testbed proved that a 5G network is capable of supporting the low latency required for this use case, even though the usefulness of the positioning data transmitted was limited by the accuracy of the GPS embedded in commercial smartphones.This work has been supported by FCT – Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020

Internet protocol over wireless sensor networks, from myth to reality

Internet Protocol (IP) is a standard network layer protocol of the Internet architecture, allowing communication among heterogeneous networks. For a given network to be accessible from the Internet it must have a router that complies with this protocol. Wireless sensor networks have many smart sensing nodes with computational, communication and sensing capabilities. Such smart sensors cooperate to gather relevant data and present it to the user. The connection of sensor networks and the Internet has been realized using gateway or proxy- based approaches. Historically, several routing protocols were specifically created, discarding IP. However, recent research, prototypes and even implementation tools show that it is possible to combine the advantages of IP access with sensor networks challenges, with a major contribution from the 6LoWPAN Working Group. This paper presents the advantages and challenges of IP on sensor networks, surveys the state-of-art with some implementation examples, and points further research topics in this area

Compósitos de WC-(Cu, Fe, Cr, Ni) obtidos por mecano-síntese

Mestrado em Engenharia de MateriaisThis work aims to study the feasibility of replacing cobalt by copper and stainless steel in tungsten carbide composite. The composites were prepared with a binder content of 12 wt% using the powder metallurgy method in which the conventional milling was replaced by high energy ball milling. To obtain a composite with high density, good microstructure uniformity and controlled phase composition, suitable for a good mechanical performance, the processing conditions of the high energy ball milling (HEBM) and sintering methods were enhanced. Within the studied parameters, the prime milling conditions were found at the rotation speed of 350 rpm and ball-to-powder weight ratio of 20:1, varying the milling times between 8-10 hours for the studied compositions. The HEBM process was able to reduce the particle size of the composite powders down to the nanoscale and a good binder homogenization was reached. After compacting, the powders were submitted to vacuum sintering, in a temperature range of 1300 – 1500ºC followed by HIP (hot isotactic pressing). This procedure allowed attaining dense compacts and introduce efficiently copper in the stainless steel binder up to 30%, without substantial decrease of the sintered relative density. The WC-SS composite powders show a significant amount of M6C phase formed during sintering, endorsed by the high reactivity of the small powder particles and the appearing of the M6C phase. Adding copper to the WC-SS composite allowed the decrease of the M6C phase formation. The WC-Cu sintered samples revealed two distinct major phases, W2C and Cu0.4W0.6 and their appearance depends on the applied sintering technique, in the case of being conventional or two stages sintering, respectively. The mechanical characterization revealed that the hardness of the WC-SS compacts is equivalent to the reported values in the literature for WC-Co. On the other hand, the fracture toughness remains below the reference values. Nevertheless, it was possible to attain a good balance between hardness and fracture toughness in the WC-(SSCu) composites, which make them promising candidates for substituting the traditional WC-Co composite.Este trabalho tem como objetivo estudar a viabilidade da substituição do ligante cobalto por cobre e aço inoxidável em compósitos de carboneto de tungsténio. Estes compósitos foram preparados com um teor de ligante de 12% pp, utilizando o método de pulverometalurgia no qual a moagem convencional foi substituída pela moagem de alta energia (MAE). Por forma a obter compósitos de elevada densidade, boa uniformidade microestrutural, e composição de fases adequada a um bom desempenho mecânico, foram otimizadas as condições de processamento das etapas de moagem de alta energia e da sinterização. As melhores condições de moagem foram verificadas com uma velocidade de rotação de 350 rpm, um rácio de peso bolas:material de 20:1 e, dependendo da composição estudada, um tempo de moagem variável entre 8 – 10 horas. Utilizando o processo de MAE foi possível reduzir o tamanho de partícula dos pós compósitos até à nanoescala e ainda obter uma boa uniformidade da distribuição da fase ligante. Após compactação, os pós foram submetidos a uma etapa de sinterização em vácuo num intervalo de temperaturas entre 1300 - 1500 °C, seguindo-se uma etapa de prensagem isostática a quente. Este método permitiu obter compactos de densidade elevada e introduzir de forma eficiente até 30% de cobre na fase ligante de aço inoxidável sem se verificarem reduções substanciais da densidade dos compactos sinterizados. Os compósitos de WC-SS apresentam uma composição de fases com uma quantidade elevada de fase M6C, formada durante a sinterização e que é favorecida nestes materiais, devido à elevada reatividade dos pós nanométricos. Contudo, a adição de cobre ao compósito WC-SS permitiu a diminuição da formação de fase M6C. As amostras sinterizadas de WC-Cu apresentam maioritariamente duas fases distintas, W2C e Cu0.4W0.6 e o aparecimento desta última fase depende da técnica de sinterização utilizada, convencional e sinterização em duas etapas respetivamente. A caracterização mecânica revelou que a dureza dos compósitos de WC-SS é equivalente aos valores indicados na literatura para os compósitos de WC-Co, enquanto a tenacidade permanece abaixo dos valores de referência. No entanto, foi possível alcançar um bom equilíbrio entre a dureza e tenacidade nos compósitos de WC-(SSCu), o que poderá permitir a sua utilização em algumas aplicações dos tradicionais carbonetos cementados de WC-Co

A geographical information system for wild fire management

he CROSS-Fire project focus on developing a grid-based framework for wild fire management using FireStation (FS) as a standalone application that simulates the fire spread over complex topography. The overall software development is made of several components: client applications, which request geo-referenced data and fire spread simulation, Spatial Data Infrastructures (SDI), which provide geo-referenced data, and the GRID, which gives support to the computational and data storage requirements. Herein we present the central WPS (Web Processing System) layer developed to support the interaction between all components of the architecture. This OGC-WS compatible layer provides the mechanism to access the grid facilities for processing and data management and including all the algorithms, calculation, or model that operates on spatially referenced data, also mediating communication with the FS console. We also describe the work that has been done to provide FS with dynamic fuel maps, by using an OGC-WCS suite of services and satellite data. This task complements the previous integration of dynamic data from meteorological stations using OGC-SWE services

CROSS-Fire : a risk management decision support system on the Grid

The CROSS-Fire project aims to develop a grid-based risk management decision support system for the Civil Protection (CP) authorities, using forest fires as the main case study and FireStation as a standalone CAD application to simulate the fire spread over complex topography. CROSS-Fire approach is based in an architecture that includes: information models, encodings, and metadata that represent the scientific knowledge associated to FireStation execution models and standards to enable the discovery and access of Web services, data repository, sensor networks and data processing facilities. To achieve the desired integration of information and services we use: i) EGEE to provide raw technological capability provision, including data management and storage, access to meta-data data bases and high-performance computing and ii) a Geospatial Information Infrastructure based on OCG-WS and SWE Web services to provide the access and management of remote geospatial data and virtualized sensor networks. This article, stresses the relevance of standards adoption of OGC-WS by describing the work that is been done to provide G-FireStation with: i) a standard-based SDI layer, based on Geoserver to exploit/enable geospatial services for data access/processing and ii) a 52N’s implementation of a OGC-SWE compatible layer, to address sensors CP data sources, such as meteorological stations data and satellite images and iii) the development of G-FireStation graphical user interface to access the platform facilities. The core of the CROSS-Fire Platform is a WPS 52North OGC standard layer divided into three interoperable components, respectively, the CROSS-Fire Business Logic, the Grid Services and Geospatial Services. WPS serves as an interface to a wide range of distributed computing resources provides the mechanism to access the grid facilities for processing and data management and including all the algorithms, calculation, or model that operates on spatially referenced data, also mediating all the communication with the portal and other GUI clients. The G-FireStation user interface that is currently under development is an open-source desktop with GIS and CAD capabilities that exploits an SDI client complying with OGC-WS and EU INSPIRE directives. It provides facilities to locate and access the spatial data infrastructure and to visualize the fire propagation, based on the native facilities of gvSig, it was also extended to support a OGC WPS client that mediate all the interactions with the core WPS service layer.Fundação para a Ciência e a Tecnologia (FCT

A platform to support civil protection applications on the GRID

The CROSS-Fire is a Portuguese NGI funded project focus-ing on the development of a grid-based risk management decision support system for the Civil Protection (CP), using forest fires as the main case study. The project defines a general approach for the development of a CP application by defining an architecture that integrates three main layers: the CROSS-Fire Platform and two external infrastructures: a Spatial Data Infrastructure (SDI) and the GRID. The CROSS-Fire Platform is defined and implemented as a set of WPS algorithms dealing with most of the functionalities of its three components: Business Logic, Grid Services and Geospatial services. The present work stresses the relevance of standards adoption: OGC-WS WCS/WFS/WMS/WPS, to exploit/enable geospatial services for data access processing, and OGC-SWE SOS to address other CP data sources, such as meteorological station networks (MSN) or satellites. The adoption of a Web Services (WS) approach allows integrating easily with existing systems typically based on WS technologies. We also present CFS, a grid user interface SDI based client, compliant with OGC and EU INSPIRE directives which allows decision makers to access the spatial data infrastructure, to launch simulations on the grid and visualize the fire propagation simulations.Fundação para a Ciência e a Tecnologia (FCT

A group-based wireless body sensors network using energy harvesting for soccer team monitoring

[EN] In team-based sports, it is difficult to monitor physical state of each athlete during the match. Wearable body sensors with wireless connections allow having low-power and low-size devices, that may use energy harvesting, but with low radio coverage area but the main issue comes from the mobility. This paper presents a wireless body sensors network for soccer team players' monitoring. Each player has a body sensor network that use energy harvesting and each player will be a node in the wireless sensor network. This proposal is based on the zone mobility of the players and their dynamism. It allows knowing the physical state of each player during the whole match. Having fast updates and larger connection times to the gateways, the information can be routed through players of both teams, thus a secure system has been added. Simulations show that the proposed system has very good performance in high mobility.This work has been partially supported by the Instituto de Telecomunicacoes, Next Generation Networks and Applications Group (NetGNA), Portugal, by Government of Russian Federation, Grant 074-U01, by National Funding from the FCT - Fundacao para a Ciencia e a Tecnologia through the PEst-OE/EEI/LA0008/2013 Project.Lloret, J.; García Pineda, M.; Catala Monzo, A.; Rodrigues, JJPC. (2016). A group-based wireless body sensors network using energy harvesting for soccer team monitoring. International Journal of Sensor Networks. 21(4):208-225. https://doi.org/10.1504/IJSNET.2016.079172S20822521

Blockchain for global vaccinations efforts: State of the art, challenges, and future directions

The emergence of the coronavirus disease 2019 (COVID-19) global crisis negatively affected all aspects of human life. One of the most important methods used worldwide to survive this global crisis is the vaccination process to circumvent the proliferation of this pandemic. Many restrictions were alleviated in many countries such as access to public facilities and events. There is a huge amount of data about vaccination campaigns that are collected and maintained worldwide. Although the vaccination data can be analyzed to find out how the alleviation of restrictions can be applied if the data management process requires preserving key aspects like trust, transparency, and availability for easy and reliable access to such data. In this regard, blockchain technology is an excellent choice for meeting the requirements and providing a secure trusted framework for global verification. In this article, the related literature on blockchain technology is surveyed and summarized for all systems that embody solutions. The pros and cons of each solution are presented and provide a comparative summary. Furthermore, a detailed analysis is given to present the current problems and provide a promising mechanism to verify the vaccinated persons anywhere in the world, in a secure manner while retaining individual privacy

Cross-Fire : a grid platform to integrate geo-referenced web services for real-time risk management

Fire propagation simulation tools are useful at different levels of forest fire management. From prescribed fire planning to fuel hazard assessment or to the development of fire suppression strategies on wildfires or even training activities. Nevertheless, real time use of such tools is still very limited among the operational authorities for several reasons: lack of good real time data, lack of training or even lack of confidence on the capabilities of actual systems, among others. Wildfire management is a relevant Civil Protection (CP) activity that involves many different and autonomous actors, from public bodies to research centres and should some how reach the general public as an information and alert system. It requires a fast and reliable risk management support system, with real-time or near real-time availability of critical geo-referenced data and settings-based forecasts for fire spreading. CP applications require a strict integration of human and physical resources that must be shared in a coordinated and effective way and be available for the whole emergency procedure. The GRID and Virtual Organizations (VO) enable such integration by providing the coordination and the sharing of the available interconnected resources (computing, storage, communication, sensors and actuators) geographically scattered across national borders. On the another hand, OGC (Open Geospatial Consortium) based geo-web services are being adopted worldwide, as the technology to support the development of complex distributed applications over grid platforms, to deal with data from many different sources, including meteorological stations and satellites. Recent work clearly showed the advantage of the OGC proposals for open standards for geospatial interchange formats, over past legacy formats and applications.Fundação para a Ciência e a Tecnologia (FCT

Bridging the gap between applications geospatial data and the Grid

Fundação para a Ciência e a Tecnologia (FCT