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A Cisco Systems é líder mundial em tecnologia para a Internet. A Cisco Networking Academy é um programa de capacitação profissional e desenvolvimento de carreiras no setor de Tecnologias de Informação (TI) para instituições de ensino e pessoas em todo o mundo. Os cursos da Cisco Networking Academy são concebidos com o objetivo da preparação para os exames de Certificação Cisco, e estão alinhados e são reconhecidos pela indústria. Estas certificações são altamente valorizadas pelos empregadores em todo o mundo, e os profissionais que as detêm estão entre os mais bem pagos na área de TI em todo o mundo. Este foi o mote para a criação da Academia Cisco da Escola Superior de Tecnologia do Instituto Politécnico de Castelo Branco (IPCB) em 2003, como um centro técnico de formação especializado em redes, que disponibiliza um vasto catálogo de cursos de formação, sendo as principais as formações CCNA (Cisco Certified Network Associate), CCNA Security e CCNP (Cisco Certified Network Professional Program). Cientes da crescente necessidade de implementação e gestão de tecnologias Cisco no mercado, e com vista a potenciar o reconhecimento das competências dos estudantes das Licenciaturas de Engenharia Informática e de Tecnologias da Informação e Multimédia do IPCB, os docentes das unidades curriculares (UCs) Redes de Comunicação de Dados e Arquitetura Internet, promoveram recentemente a reformulação dos seus conteúdos programáticos, alinhando-os com o catálogo de formação CCNA, bem como das metodologias de ensino e de avaliação para potenciar o processo de ensino aprendizagem. Estas UCs têm agora uma forte componente prática, com aulas ativas combinadas com o extensivo programa de e-learning da Cisco que apoia o autoestudo e autoaprendizagem e permite o uso de simuladores de redes. Este artigo reflete sobre o impacto das alterações introduzidas nas UCs, na motivação e o interesse dos alunos nos conteúdos e atividades desenvolvidas, na avaliação pedagógica e da atividade do docente, e na taxa de sucesso.

Vehicular Delay-Tolerant Networks (VDTNs) are a networking paradigm based on concepts of Delay-Tolerant Networks (DTNs) and Opportunistic Networks. Opportunistic contacts, intermittent connectivity, frequent network partition, long propagation delays and no contemporaneous end-to-end paths characterize VDTNs. VDTNs have been proposed to interconnect developing communities, or to implement disaster recovery networks when all other networks fail. Other possible application scenarios for these networks include traffic monitoring, accident warnings, advertisements, or data gathering applications. The diversity of these network environments introduces challenging issues related to the architecture, protocols design, interoperability, security, management, and stability of VDTNs. This communication starts with the presentation of VDTNs architecture. In the sequence, it focuses on problems that arise from low network node density and missed transmission opportunities, vehicle movement models, constrained network resources on routing strategies, and scheduling and drop policies.

Today, despite increased information demand from consumers and food chain players alike, Europe’s food businesses and farmers are slow at adopting digital technologies. This is due in part to the inherent complexities of relevant products and processes, and in part to the dynamically changing open network organization of the food sector with its multitude of SMEs, its cultural diversity, its differences in expectations and in the ability to serve transparency needs. The agri-food sector needs to take more advantage of the potential of digital technologies. Relevant technologies may include Internet of Things, Artificial Intelligence, Big Data technologies, remote and localized sensing. This chapter will engage the agri-food community in supporting the development of solutions to remove the barriers to adoption of digital technologies, taking a multi-actor approach across different supply chains (conventional and organic) from farm to fork.

This paper presents a wireless mesh network testbed based on ESP8266 devices using painlessMesh library. It evaluates its feasibility and potential effectiveness as a solution to monitor perishable goods, such as fresh fruit and vegetables, which are often stored and transported inside refrigerated containers. Performance testing experiments with different numbers of nodes and traffic loads and different message payload sizes are conducted under unicast transmission. The impact on network performance is evaluated in terms of delivery ratio and delivery delay, which, consequently, affect the energy consumption and, hence, network lifetime. The results of this investigation are an important contribution to help researchers to propose mechanisms, schemes, and protocols to improve performance in such challenging networks.

Esta apresentação centra-se num estudo que visa validar e avaliar o uso de técnicas de visão computacional na deteção de defeitos em pavimentos rodoviários. Apresenta os conceitos relacionados com a temática e as soluções apontadas na literatura, discute os pontos fortes e as limitações das mesmas e identifica pontos em aberto. Após esta análise, apresenta uma avaliação de desempenho das técnicas mais promissoras para solução deste problema.

Wireless mesh networking (WMN) is a continuous growing technology that has an important role towards the vision of smart agriculture. This work presents the setup and performance assessment of a wireless mesh network testbed developed within the context of PrunusPós project to collect data such as temperature and humidity of fruit crates or containers when stored or transported in refrigerated chambers. The testbed is based on ESP8266 devices connected in a wireless mesh using the painlessMesh library. A performance evaluation study was conducted with different numbers of nodes, traffic loads, and message payload sizes under unicast and broadcast communication. The impact on network performance is evaluated in terms of delivery ratio and delivery delay. This study will guide the future development of mechanisms, schemes and protocols that provide efficient bandwidth utilization and energy-efficient computing for the PrunusPós project WMN.

Este artigo visa fazer uma contextualização do conceito de Internet das Coisas (IoT), uma nova abordagem que resulta da dinamização da multipluralidade de plataformas passíveis de interligar e com os quais é possível estabelecer comunicação em rede. Estas afetam, cada vez mais, a qualidade de vida dos seus utilizadores e acabam por ter uma repercussão quotidiana na forma como estes extraem informação no meio envolvente, muitas vezes de forma invisível. No curso deste documento, também será feita uma exposição dos dispositivos de suporte que lhe estão associados, desde os microcontroladores que os operam, até aos sensores e/ou outros dispositivos, que não são mais que ferramentas que recolhem e comunicam a informação.

There are contexts where TCP/IP is not suitable for performing data transmission due to long delays, timeouts, network partitioning, and interruptions. In these scenarios, mobile opportunistic networks (MONs) are a valid option, providing asynchronous transmissions in dynamic topologies. These architectures exploit physical encounters and persistent storage to communicate nodes that lack a continuous end-to-end path. In recent years, many routing algorithms have been based on social interactions. Smartphones and wearables are in vogue, applying social information to optimize paths between nodes. This work proposes Refine Social Broadcast (RSB), a social routing algorithm. RSB uses social behavior and node interests to refine the message broadcast in the network, improving the delivery probability while reducing redundant data duplication. The proposal combines the identification of the most influential nodes to carry the information toward the destination with interest-based routing. To evaluate the performance, RSB is applied to a simulated case of use based on a realistic loneliness detection methodology in elderly adults. The obtained delivery probability, latency, overhead, and hops are compared with the most popular social-based routers, namely, EpSoc, SimBet, and BubbleRap. RSB manifests a successful delivery probability, exceeding the second-best result (SimBet) by 17% and reducing the highest overhead (EpSoc) by 97%.

Smart lockers are intelligent storage units that are increasingly being adopted to help solving the last mile problem. This paper focuses on the concept of an individual smart locker that can be installed at the entrance of a residential house. First, the operational principle and advantages of this concept are discussed. Then, the design, development and implementation of a functional prototype is demonstrated. The prototype was submitted to tests and can be used as a proof of concept.

This paper presents the proposal, implementation and validation of a low cost fault-tolerant functional prototype for livestock monitoring. This prototype uses IoT devices, ESP8266 and ESP32, creating a mesh network, managed by the painlessMesh library, with WiFi and LoRa technologies. It allows, for instance, the collection of vital signs from animals. In comparison with the traditional method of livestock examination, this cost-efficient approach reduces manual labor and saves working time. It also improves animal health, increases profits and decreases the environmental footprint.

This paper presents the performance evaluation of a wireless sensor mesh network, for monitoring temperature and humidity in horticultural products when transported in truck galleys. For this purpose a software solution was proposed using ESP8266 devices powered by batteries. The mesh network was managed by the painlessMesh library. The proposed solution aims to minimize the energy consumption of the sensor nodes. The validation of the solution was performed in an area simulating a galley of a truck, where five sensor nodes and a root node were distributed. The tests were developed considering four different models involving variations in messages delivery confirmation, number of attempts until successful delivery and duty cycle duration of the nodes. The performance evaluation of the solution aimed to determine, connectivity rate, sending rate after connection and delivery rates of the first and second attempts. The results obtained show that the message delivery confirmation does not bring added value to the solution, contributing only to increase energy consumption. The use of synchronous duty cycles also showed worse results than the asynchronous use. These results allow the creation of a knowledge base for the use of this solution in a real context.

The continuous rise in the world’s population has increased the need for food, resulting in a rise of agricultural holdings to ensure the supply of these goods directly to the populations and indirectly to all processing industries in the food business. This situation has led agriculture to reinvent itself and introduce new technics and tools to ensure tighter control of the crops and increase yields in food production. However, the lack of labor coupled with the evolution of weeds resistant to herbicides created a crisis in agricultural food production. However, with the growing evolution in electronics, automation, and robotics, new paths are emerging to solve these problems. A robotic rover was designed to optimize the tasks of weed control and collection of fallen fruits of an orchard. In weed control, a localized spraying system is proposed, therefore reducing the amount of applied herbicides. With fruit collection, it is possible to direct fallen fruits for animal feeding and possible to reduce microbial activity on the next campaign crops, therefore avoiding damage. This study proposes the simulation of this robotic rover on robotic simulation software. It also proposes the replication of a similar environment of an orchard to generate an algorithm that controls the rover on the tasks of localized spraying and fallen fruit collection. Creating and testing these algorithms by using a robotic simulator speed up and ease the evaluation of different scenarios and hypotheses, with the added benefit of being able to test two tasks simultaneously. This method also allows greater freedom and creativity because there are no concerns about hardware damage. It should also be noted that development costs are very low.

This survey presents approaches and technologies for livestock identification, vital signs monitoring and location tracking. It first introduces the related concepts. Then, provides an analysis of existing solutions and highlights their strengths and limitations. Finally, it presents key challenges in the field, and discusses recent trends that must be factored in by researchers, implementers, and manufacturers towards future developments in the area.

As redes de sensores sem fios são uma tecnologia emergente que é frequentemente utilizada para monitorizar pontos ou objectos de interesse numa área. Apesar das suas muitas aplicações, este tipo de rede é frequentemente limitado pelo facto de ser muito difícil fornecer energia aos nós continuamente, forçando a utilização de baterias, o que limita as suas operações. A densidade da rede pode também levar a outros problemas. Redes esparsas requerem transmissões mais fortes e têm pouca redundância, enquanto as redes densas aumentam as hipóteses de sobre-audição e interferência. Para resolver estes problemas, vários novos protocolos de controlo de acesso ao meio (MAC) têm sido desenvolvidos ao longo dos anos. O objectivo deste estudo é avaliar a eficácia dos protocolos T-MAC, B-MAC, e RI-MAC numa rede de densidade variável utilizada para recolher dados dentro de camiões de carga que transportam frutos perecíveis. Este trabalho faz parte do projecto PrunusPós, que visa aumentar a eficiência da cultura de pêssegos e cerejas em Portugal.

Este trabalho apresenta o desenho e implementação de um protótipo funcional para avaliar e validar a utilização de técnicas de visão computacional, na identificação de contentores de resíduos no contexto de uma cidade inteli- gente. Este protótipo recorre à utilização de uma rede neuronal convolucional YOLO e de um microcomputador Jetson Nano da Nvidia. Comparativamente ao método atual de identificação de contentores de resíduos por radiofrequência, esta abordagem é mais ágil e diminui os recursos necessários para implementa- ção, contribuindo para poupar nos gastos logísticos e de implementação da gestão inteligente de resíduos.

This survey focuses on the benefits of smart lockers and their potential contribution in the last mile problem. It first introduces the related concepts. Then, categorizes existing solutions and identifies the similarities and differences. Further, their strengths and limitations are discussed. Finally, it presents key challenges in the field, and discusses envisionedfuture research directions that mustbe factored in by researchers, implementers, and manufacturers to increase the acceptance of smart lockers and to improve their security.

There are contexts where communication with TCP/IP protocol is not possible due to the lack of infrastructure or a reliable and continuous data transmission. In this cases, alternatives such as Opportunistic Networks (OPPNets) are valid. Such challenging conditions are common in rural areas and are a significant obstacle for the deployment of eHealth technologies for older adults. Considering this context, the present work introduces Interest-based System for Communication in Isolated Areas (ISCA), an OPPNet architecture for remote monitoring and emergency detection in ageing people who live alone. For this, the energetic requirements are considered, providing efficient and sustainable operation. The proposal makes use of a routing algorithm based on interests which enables asynchronous communication among entities. ISCA is evaluated over a realistic scenario and compared with similar state-of-the-art solutions. Experimental results show that ISCA notably improves the delivery probability with an enhancement of 52.25% in comparison to the second best alternative and provides a suitable average latency. Moreover, it also achieves better performance in terms of overhead and hops number compared to the other studied protocols.

Alavancagem da atividade económica nas pequenas e médias empresas de sectores estratégicos e tradicionais: Encorajamento na utilização de novas tecnologias, Oportunidade enorme para as novas TIC nas empresas agroalimentares, Incorporar recursos inovadores com valor acrescentado, melhorar as competências de atividade das PME, promover a modernização do sector empresarial regional, a utilização das TIC irá fomentar a economia e a competitividade dos sectores agro-alimentares tradicionais