Search results for " Transformation"
showing 10 items of 1043 documents
Finite difference thermal model of a latent heat storage system coupled with a photovoltaic device: Description and experimental validation
2014
Abstract The use of photovoltaic (PV) systems has been showing a significant growth trend but for a more effective development of this technology it is essential to have higher energy conversion performances. Producers of PV often declare an higher efficiency respect to real conditions and this deviation is mainly due to the difference between nominal and real temperature conditions of the PV. To improve the solar cell energy conversion efficiency many authors have proposed a methodology to keep lower the temperature of a PV system: a modified PV system built with a normal PV panel coupled with a Phase Change Material (PCM) heat storage device. In this paper is described a thermal model ana…
Novel test bed for induction heating power supplies
2006
Power supplies used in induction heating industrial applications must be entirely tested after its manufacturing in order to assure its security and reliability by means of a full power running test of several hours of duration. Nowadays this test is done with a dissipative load which implies a large waste of energy. This paper proposes a new high efficiency test system for induction heating generators. It incorporates a regenerative electronic load which allows an extraordinary improvement of the efficiency of this test with an important economical and ecological benefit.
A small scale prototype of a wave energy conversion system for hydrogen production
2015
In this paper a small scale prototype of sea wave energy converter for hydrogen production and storage is presented. Laboratory prototypes of the wave energy converter device and sea water electrolyzer are presented. Experimental results are shown. A cost-effective and efficient power electronics system is designed. Experimental waveforms of the wave energy converter are imported in the power electronics simulation model to simulate the whole system as closely as possible to its effective behavior. Simulation results are shown to test the efficiency of the proposed solution.
Design issues for wind farms grid tied Inverter
2017
In this paper the Authors give indications for the design of a grid tied Voltage Source Inverters (VSI) aimed to optimal use in energy conversion from wind source. In particular, the design of the inverter is more focused on the control system planning, with a particular glance on the grid synchronization problem. After the exposition of general issues concerning renewable energies and associated topics, the case of a grid tied inverter is considered and a methodology of design is sketched starting from the consideration of the DC side and also considering the power device losses, the protection issue against over voltages and over-currents, snubber circuits, heat sinks and, finally the con…
In sewer processes: mathematical model development and sensitivity analysis.
2009
Until now the majority of sewer networks in Italy have been built and managed considering small as well as local wastewater treatment plants (WWTPs). However, pushed by Italian and EU regulations, centralised and large WWTPs are becoming more common in Italy. One major technical aspect caused by the changing from local to centralised WWTPs is the development of significant in-sewer processes. These processes are also emphasized by the building of long interceptor sewers characterized by high hydraulic retention times and absence of tributary sewers. In this paper a model derived from the well known WATS model (Wastewater Aerobic/anaerobic Transformation in Sewers) has been set up and applie…
Experimental Test and Simulations on a Linear Generator-Based Prototype of a Wave Energy Conversion System Designed with a Reliability-Oriented Appro…
2017
In this paper, we propose a reliability-oriented design of a linear generator-based prototype of a wave energy conversion (WEC), useful for the production of hydrogen in a sheltered water area like Mediterranean Sea. The hydrogen production has been confirmed by a lot of experimental testing and simulations. The system design is aimed to enhance the robustness and reliability and is based on an analysis of the main WEC failures reported in literature. The results of this analysis led to some improvements that are applied to a WEC system prototype for hydrogen production and storage. The proposed WEC system includes the electrical linear generator, the power conversion system, and a sea-wate…
Digital Transformation of Centru Region – Romania. Needs Assessment
2020
Abstract Competitiveness represents a never-ending moving target for any institution/entity, no matter the level of analysis (micro - companies /public administrations, mezzo - industries / national regions, or macro - countries / world regions); but its determinants (or key success factors) are changing, as ages go by, asking for continuous watch and strategic flexibility. With digital technology nowadays disrupting (almost) every aspect of human life, while framing a new age - of digitalization being both a source of competitiveness (for the industry leaders - whatever the “industry” might be), and (just) a prerequisite for survival (or doing business) for almost everyone else, the Europe…
Beyond the “ivory tower”. Comparing academic and non-academic knowledge on social entrepreneurship
2021
The increasing relevance of societal challenges has recently brought social entrepreneurship to the fore due to its capacity to leverage entrepreneurial processes to achieve social value while ensuring profits. In this study, we apply an experimental research method to analyse the concept of social entrepreneurship comprehensively. More specifically, we develop bibliometric analysis and web crawling techniques to gather information related to social entrepreneurship from Scopus and Wikipedia. We conduct a comparative network analysis of social entrepreneurship’s conceptual structure at academic and non-academic levels. This analysis has been performed considering scientific articles’ keywor…
Romania’s SMEs on the Way to EU’s Twin Transition to Digitalization and Sustainability
2021
Abstract European Commission’s six priorities for 2019-2024 are all in line with and leverage each other to support Europe’s twin transition to digitalization and sustainability; aiming to address the challenges posed by the COVID-19 pandemic, The Recovery Plan for Europe adds resilience as key dimension of EU’s progress, while reinforcing its commitment to the green and digital transformation. Counting for more than 99% of the enterprises, employing about two of three people, and generating more than a half of the value added - with similar weights as concerns Romania - EU’s SMEs are the engine of Europe's economy, therefore essential contributors to these transformative processes - as emp…
Unraveling metabolic flexibility of rhodococci in PCB transformation
2021
International audience; Even though the genetic attributes suggest presence of multiple degradation pathways, most of rhodococci are known to transform PCBs only via regular biphenyl (bph) pathway. Using GC-MS analysis, we monitored products formed during transformation of 2,4,4′-trichlorobiphenyl (PCB-28), 2,2′,5,5′-tetrachlorobiphenyl (PCB-52) and 2,4,3′-trichlorobiphenyl (PCB-25) by previously characterized PCB-degrading rhodococci Z6, T6, R2, and Z57, with the aim to explore their metabolic pleiotropy in PCB transformations. A striking number of different transformation products (TPs) carrying a phenyl ring as a substituent, both those generated as a part of the bph pathway and an array…