Encontrados 43 documentos, a visualizar página 1 de 5
Resilient wireless sensor actor networks through multi-objective self-adaptation
Gomes, Ruben; Correia, NoéliaWireless Sensor Actor Networks (WSAN) are a key enabler of Internet of Things applications that demand timely and reliable data exchange under dynamic conditions. Among the various domains that benefit from these networks, precision agriculture stands out, demanding adaptive strategies for effective monitoring and control. This study proposes a reinforcement learning approach that leverages the Operationalizati...
Spectrum sharing for LTE and 5G-NR coexistence
Busari, Sherif Adeshina; Correia, Noélia; Saghezchi, Firooz B.; Mumtaz, Shahid; Rodriguez, JonathanSpectrum sharing provides a rapid migration pathway toward 5G by enabling the coexistence of 4G LTE and 5G new radio (NR) that share the same spectrum. Due to significant differences in the LTE and 5G-NR air interfaces, several enablers are required to facilitate the spectrum sharing. In this study, we explore the coexistence features and investigate their impacts on network performance. For static and dynamic ...
Optimizing resource reuse in the web of things
Gomes, Ruben; Correia, NoéliaThe Web of Things enables collecting vast amounts of data about the environment and sharing them over the Internet. Its popularity, however, has brought challenges under constrained environments, such as an increase in the number of connected devices, and a consequent additional consumption of resources, leading to the deterioration of communications and application response times. By discovering and reusing se...
A2PC: augmented advantage pointer-critic model for low latency on mobile IoT wi...
Carvalho, Rodrigo; Al-Tam, Faroq; Correia, NoéliaAs a growing trend, edge computing infrastructures are starting to be integrated with Internet of Things (IoT) systems to facilitate time-critical applications. These systems often require the processing of data with limited usefulness in time, so the edge becomes vital in the development of such reactive IoT applications with real-time requirements. Although different architectural designs will always have adv...
Mobility planning of LoRa gateways for edge storage of IoT data
Carvalho, Rodrigo; Correia, Noélia; Al-Tam, FaroqLoRaWAN is now a leading technology in IoT developments due to its low power consumption and simple deployment features. Despite being termed a long-distance technology, its coverage is often hampered by the harsh propagation environment. In such cases, a very cost-effective solution is to use mobile gateways for both data collection and delivery at specific places of the edge, avoiding the need for cellular co...
Attention-based model and deep reinforcement learning for distribution of event...
Mazayev, Andriy; Al-Tam, Faroq; Correia, NoéliaEvent processing is the cornerstone of the dynamic and responsive Internet of Things (IoT). Recent approaches in this area are based on representational state transfer (REST) principles, which allow event processing tasks to be placed at any device that follows the same principles. However, the tasks should be properly distributed among edge devices to ensure fair resources utilization and guarantee seamless ex...
Resource design in federated sensor networks using RELOAD/CoAP overlay architec...
Rodrigues, Luis; Guerreiro, Joel; Correia, NoéliaSensor networks can be federated for wide-area geographical coverage using RELOAD/CoAP architectures. In this case, proxy nodes of constrained environments form a P2P overlay to announce device resources or sensor data. Although this is a standard-based solution, consistency problems may arise because P2P resources (data objects stored at the overlay network) may end up including similar device resource entries...
A Comparative study of software architectures in constrained device IoT deploym...
du Plessis, Shani; Correia, NoéliaThe Internet of Things (IoT) is an area that has consistently seen growth and development and will no doubt continue to do so. One group of IoT devices - constrained devices - has seen significant developments in recent years. With the advent of constrained devices in almost every area of life, e.g. industrial, leisure and medical, this group of devices is well worth studying. Clearly, resource management is a ...
Optimization of mixed numerology profiles for 5G wireless communication scenarios
Correia, Noélia; Al-Tam, Faroq; Rodriguez, JonathanThe management of 5G resources is a demanding task, requiring proper planning of operating numerology indexes and spectrum allocation according to current traffic needs. In addition, any reconfigurations to adapt to the current traffic pattern should be minimized to reduce signaling overhead. In this article, the pre-planning of numerology profiles is proposed to address this problem, and a mathematical optimiz...
Performance evaluation of radio resource schedulers in LTE and 5G NR two-tier H...
Busari, Sherif Adeshina; Correia, Noélia; Mumtaz, Shahid; Rodriguez, Jonathan; Saghezchi, Firooz B.Network performance is critically dependent on the employed radio resource scheduler (RRS). The impact becomes even more significant in 5G ultra-dense networks due to the challenges of complicated base station distribution, user association, load balancing and inter-cell interference, among others. Using a combination of three popular schedulers (i.e., round robin (RR), proportional fairness (PF) and best chann...