21 documents found, page 1 of 3
Solid-state transformer: the catalyst for resilient and sustainable smart grids
Coelho, Sérgio; Dionizio, Anderson; Cunha, José; Monteiro, Vítor Duarte Fernandes; Afonso, João L.This paper explores the transformative role of solid-state transformers (SSTs) in enhancing the performance of smart grids and microgrids, focusing on their technological capabilities and contribution to sustainability. Renowned for their flexibility, adaptability, and scalability, SSTs are crucial for improving the resilience of electrical systems, particularly in dynamic infrastructures with multiple load and...
Artificial intelligence tools in community pharmacy: a literature review
Castro, Francisco; Pires, Gonçalo; Pinto, Isabel C.; Cunha, José; Nascimento, Luís; Taboada Costa, XavierCommunity pharmacies play a vital role in public health, serving as the first point of contact for many patients. With the increasing workload and complexity of care, artificial intelligence (AI) is being explored as a way to enhance pharmaceutical services [1-3]. Objective: This literature review aims to explore the current AI-based hardware and software technologies applied in community pharmacy, the barriers...
Examining the technological and environmental impact of solid-state transformer...
Coelho, Sérgio; Cunha, José; Monteiro, Vítor Duarte Fernandes; Afonso, João L.This paper assesses the impact of incorporating solid-state transformers (SST) into smart grids and microgrids, analyzing their benefits in both technological and environmental dimensions. Renowned for their flexibility and transformative capabilities, SST demonstrate the aptitude to enhance interoperability among diverse technologies. Notable features include fault tolerance mechanisms, the mitigation of power...
Railway train main power converter: Model predictive current control of a modul...
Monteiro, Vítor Duarte Fernandes; Cunha, José; Afonso, João L.In electric railway trains two main power systems can be distin-guished: the system of the power propulsion and the system of the auxiliary power services. Consequently, since the train is supplied from the catenary in AC, the use of an AC to DC power converter is indispensable. This paper pro-poses the application of a modular multilevel converter (MMC) as main power converter (i.e., interfacing the AC catenar...
Railway auxiliary power supply system: A modular multilevel converter approach
Rodrigues, Nuno; Cunha, José; Monteiro, Vítor Duarte Fernandes; Afonso, João L.When it comes to power railway systems, two main aspects must be considered: (i) the power of the propulsion of the train, which is responsible for the movement of the train; (ii) the power of the auxiliary services, which is responsible for the power inside the train for commodity and service of the passengers. As such, two different converters are used, namely the propulsion converter and the static converter...
Development and experimental validation of a reduced-scale single-phase modular...
Rodrigues, Nuno; Cunha, José; Monteiro, Vítor Duarte Fernandes; Afonso, João L.With special emphasis in recent years, an increase has been verified not only in demand but also in the price of electricity, arising the need to develop more reliable and efficient electrical energy conversion systems. In this context, emerges the utilization of the modular multilevel converter (MMC) based on submodules. The key to the MMC is modularity, which allows the converter to reach higher performance l...
Technical and economical evaluation of modular multilevel converters for the el...
Rodrigues, Nuno; Cunha, José; Monteiro, Vítor Duarte Fernandes; Afonso, João L.Over the past few years, it has been verified a raise in the demand, as well as the price of electricity, urging the need for the development of more efficient power converting systems. Two of the most used power converters are the AC-DC, commonly known as rectifier, and the DC-AC, commonly known as power inverter. There are many different topologies for both the referred converters, but one of the most common ...
Modular multilevel converter: A comparison of pulse-width modulation and curren...
Rodrigues, Nuno; Cunha, José; Monteiro, Vítor Duarte Fernandes; Afonso, João L.With the constant increase of power converters in industry, the study and comparison of control techniques for these converters are of paramount importance to optimize their functioning, as well as to improve their efficiency. This paper presents a comparison of the most relevant digital control techniques of pulse-width modulation and current control for a modular multilevel converter (MMC), which is a power c...
Cu(In,Ga)Se2 based ultrathin solar cells: the pathway from lab rigid to large s...
Lopes, Tomás; Teixeira, Jennifer; Curado, Marco; Ferreira, Bernado; Oliveira, Antonio; Cunha, José; Monteiro, Margarida; Violas, André; Barbosa, JoãoFor the first time, the incorporation of interface passivation structures in ultrathin Cu(In,Ga)Se2 (CIGS) based solar cells is shown in a flexible lightweight stainless-steel substrate. The fabrication was based on an industry scalable lithography technique - nanoimprint lithography (NIL) - for a 15x15 cm2 dielectric layer patterning, needed to reduce optoelectronic losses at the rear interface. The nanopatter...
Encefalomielite aguda disseminada – pós-infecção por Herpes Vírus 6
Amorim, Joana; Guerra, Isabel Couto; Lima, Rosa; Cunha, José; Carrilho, Inês; Ramos, AnaIntrodução: A encefalomielite aguda disseminada (ADEM) é uma doença desmielinizante monofásica do sistema nervoso central (SNC) imunomediada. O quadro clínico inicial pode ser inespecífico, mas traduz geralmente envolvimento da substância branca em várias localizações do SNC, sendo a ressonância magnética (RM) do neuroeixo o exame complementar de diagnóstico de eleição. Caso clínico: Criança com 16 meses, inter...