Search results for "Power"
showing 10 items of 5099 documents
La qualità del servizio civile nazionale: prospettive, criticità e possibili interventi per l'avvio di processi di empowerment individuale, organizza…
2008
Yhteisövoimainen oppimisprosessi : substantiivinen teoria aikuisten ryhmässä oppimisen kokemuksista
2018
The aim of this study was to build a conception as well as a substantive theory of adult learners’ group learning. The framework for this study is andragogy, which places the life context of adult learners at the center of the learning process (Knowles 1990). This study has been carried out using grounded theory as a research methodology. Hermeneutics offers a broad scientific paradigm for the understanding of group learning as a phenomenon, whereas grounded theory offers a concrete tool for analyzing data and developing a substantive theory. In this approach, the theory emerges gradually in open interaction between a researcher and the data (Glaser 1992). The informants for this study were…
Behaviour of the erythrocyte deformability and nitric oxide metabolites in unprofessional athletes
2009
Wykorzystanie energii wiatru występującego w warstwie przygruntowej oraz architektonicznej
2016
W pracy przedstawiono wyniki analiz możliwości wykorzystania energii wiatru za pomocą mikro turbin wiatrowych. Przeanalizowano możliwość wykorzystania energii wiatru występującego w warstwie przygruntowej oraz architektonicznej. Zaproponowano zastosowanie układu mikroelektrowni wiatrowej o mocy 2 kW na potrzeby pojedynczego gospodarstwa domowego.Określono opłacalność zastosowania tego typu mikroelektrowni w warunkach wietrzności panujących w Opolu.
Efficient Power Allocation for Multi-Cell Uplink NOMA Network
2019
Digital technologies are rapidly shaping the modern concepts of urbanization. It is a key element of developing practical smart cities of the future. In fact, they are the catalyst for the increasing networking of all areas of life in a smart city. Recent development in the domain of communication technologies has opened new avenues to realize the concept of smart cities. One of such communication technology is non-orthogonal multiple access (NOMA) for future cellular communications. This article, therefore, focuses on the interference management of uplink cellular NOMA systems. Specifically, we propose a power optimization technique for NOMA to improve the sum-rate in a multi-cell environm…
Transmission Optimization and Resource Allocation for Wireless Powered Dense Vehicle Area Network With Energy Recycling
2022
The wireless-powered communication paradigm brings self-sustainability to the on-vehicle sensors by harvesting the energy from radiated radio frequency (RF) signals. This paper proposes a novel transmission and resource allocation strategy for the scenario where multiple wireless powered vehicle area networks (VAN) co-existed with high density. The considered multi-VAN system consists of a remote master access point (MAP), multiple on-vehicle hybrid access points (HAPs) and sensors. Unlike previous works, we consider that the sensors can recycle the radiated radio frequency energy from all the HAPs when HAPs communicate with MAP, so the dedicated signals for energy harvesting (EH) are unnec…
An Energy-Autonomous Wireless Sensor with Simultaneous Energy Harvesting and Ambient Light Sensing
2021
Wireless sensor nodes (WSNs) are generally powered by batteries, which results in a substantial limitation to the places where the nodes can be installed, to the maximum number of deployable devices, and to the node lifetime. To meet the demand for Internet-of-Things (IoT) applications that require a large number of maintenance-free, low cost, wireless sensor nodes, this paper proposes a wireless sensor platform with a single photovoltaic transducer that performs the dual role of harvesting energy and sensing ambient light. This dual use allows even smaller and cheaper nodes that do not require any form of supporting external power, with a reduced component count. The device implements off-…
A magnetostrictive generator for sensors network
2017
In this paper we present a vibration harvesting electric power generator based on magnetostrictive effect for sensors network in hazardous area and we validate it experimentally. The generator has been designed by using Dynamic Preisach hysteresis Model (DPM). DPM is a development of classical Preisach Model which is able to include dynamical features in the mathematical model of hysteresis. We measure the output power capability of the generator and we estimate its power density generation capability.
Axial Flux Permanent Magnet Synchronous Generators for Pico Hydropower Application: A Parametrical Study
2022
A pico hydropower plant is an energy harvesting system that allows energy production using the power of the water flowing in small watercourses, and in water distribution network. Axial Flow Flux Permanent Magnet Synchronous Generator (AFPMSG) are particularly suitable for this application, being efficient machines that achieve high power with small dimensions. This paper presents a parametrical study of several configurations and topologies of three-phase and single-phase AFPMSG, for pico hydropower application, to assess the most suitable dimensional characteristics for the most energy production using a safe voltage of 25 V. The AFPMSGs here considered has a simple single stator and roto…
Optimal matching between optical rectennas and harvester circuits
2017
This paper deals with optimal coupling issues between rectennas and harvesting circuits. An optical rectenna consists of a nanoantenna usually coupled with an ultra-high speed rectifier. These devices aim to receive and convert solar and thermal radiation in a DC voltage, while a harvester circuit provides the energy to be stored. The rectenna impedance is influenced both by its structure and by the rectifying diode, the harvester circuit impedance has to be matched to optimize the power transfer. The purpose of this contribution is to discuss the best impedance conditions by taking into account the constraints that are due to the individual devices the conversion system consist of. Finally…