Search results for "POWER"
showing 10 items of 5099 documents
Non-destructive and clean prediction of aviation fuel characteristics through Fourier transform-Raman spectroscopy and multivariate calibration
2003
Abstract The combination of Fourier transform (FT)-Raman spectroscopy and partial least squares (PLS) regression is proposed to be used in off-line kerosene quality control. Here, six important physico-chemical properties have been studied: Abel flash point, initial boiling point (IBP), 10% of distilled sample, final boiling point (FBP), total percentage of aromatic compounds (% aromatics) and viscosity. The Raman spectra were obtained directly from standard 2 ml glass vials ( 12 mm ×32 mm), using a Bruker RFS 100 FT-Raman spectrometer, equipped with a 1064 nm Nd:YAG laser and a Ge detector, in back-scattering mode and accumulating 25 scans (150 s acquisition time) with a laser power of 30…
A preliminary assessment of a detailed two stream short-wave narrow-band model using spectral radiation measurements
1997
Abstract A data bank of measurements of global, direct and diffuse solar spectral irradiances at ground level for clear skies has been compiled for Valencia (Spain) dating back to December 1992. The measurements were made with a commercial Li-cor 1800 spectroradiometer with a range of 300–1100 nm and a spectral resolution of 6 nm. A preliminary comparative assessment has been carried out between the experimental data and model data. The chosen model was a detailed narrow-band model (208 spectral intervals from 0.2 to 4 μm) developed at the “Laboratoire d'Optique Atmospherique (LOA)” of the University of Lille (France). This plane-parallel multilayer model uses a two-flux method to solve the…
Experimental assessment of application of gravimetric measurements for pneumatic conveying in horizontal pipelines
2008
Abstract Available theoretical considerations and practical experiments usually concern aspiration in the vertical pipelines, where the procedure of making measurements is universally known and it does not express any reservations. However, it is often necessary to conduct test in the systems of horizontal conveying of solgas, where the conditions of taking a representative sample, even for the sake of the significant effect of the gravitational force, many vary from those suggested for measurements in the systems with vertical flow. The present paper contains the results of tests which determine usability of the gravimetric method in measurements of flow parameters of two-phase gas–solid m…
Measurement technique for real-time and low-cost biosensing using photonic bandgap structures
2011
We present a sensing technique based on using photonic bandgap structures where only the output power is monitored, without the need of tunable sources or spectrum analyzers, thus providing a real-time and low-cost system.
Circuits and excitations to enable Brownian token-based computing with skyrmions
2021
Brownian computing exploits thermal motion of discrete signal carriers (tokens) for computations. In this paper we address two major challenges that hinder competitive realizations of circuits and application of Brownian token-based computing in actual devices for instance based on magnetic skyrmions. To overcome the problem that crossings generate for the fabrication of circuits, we design a crossing-free layout for a composite half-adder module. This layout greatly simplifies experimental implementations as wire crossings are effectively avoided. Additionally, our design is shorter to speed up computations compared to conventional designs. To address the key issue of slow computation base…
The Imperative of Addressing the Contemporary Crisis of Economics with Spiritual Intelligence
2013
Abstract The current global economic crisis has also drawn an increasingly obvious crisis of the economic theories. Thereby are more and more voices that calls for quitting the rather mechanistic, mathematical, determinist or pure rational approaches in favor of either sociological, psychological, historical, cultural or merely ethical ones, or, most often, a combination of some or all of these. In this paper I argue that the most needed approaches are now the anthropological ones that start from the spiritual considerations about human intelligence.
Modeling and Experimental Validation of a Voltage-Controlled Split-Pi Converter Interfacing a High-Voltage ESS with a DC Microgrid
2023
The Split-pi converter can suitably interface an energy storage system (ESS) with a DC microgrid when galvanic isolation is not needed. Usually, the ESS voltage is lower than the grid-side voltage. However, limitations in terms of the ESS current make the use of a high-voltage ESS unavoidable when high power levels are required. In such cases, the ESS voltage can be higher than the microgrid voltage, especially with low microgrid voltages such as 48 V. Despite its bidirectionality and symmetry, the Split-pi exhibits a completely different dynamic behavior if its input and output ports are exchanged. Thus, the present work aims to model the Split-pi converter operating with an ESS voltage hi…
New stage-discharge relationship for inclined non-rectangular weirs
2018
Abstract In this paper, the outflow process of inclined non-rectangular weirs is studied applying the dimensional analysis and the incomplete self-similarity theory. At first, a new stage-discharge equation, applicable for the non-rectangular weirs having a different geometrical shape (parabolic, semicircular, inverted semicircular), is theoretically deduced using a characteristic width. Then, this power stage-discharge relationship (Eq. (17) ) is calibrated and tested using measurements carried out by Raiknar for parabolic, semicircular and inverted semicircular weirs having different inclination respect to the vertical (10°, 20°, 30°, 40° and 45°). For each geometrical shape, the analysis…
A New Method for the Price Determination of the Reactive Power Supply
2006
This paper addresses the development of an accurate model for the pricing of reactive power supply as an ancillary service. Reactive power supply is one of the most important ancillary services in the field of transmission systems security. The present work is focused on building a reactive power market at which the Distributors can also take part in injecting reactive power at the connected HV/MV nodes. The authors have studied the particular case of the reactive power supplied by sub-transmission or distribution networks, connected to the nodes of the transmission system. The aim of this work is to establish a reactive power price by crossing demand and offer curves.
Review of photovoltaic status in a European (EU) perspective
2011
In the EU continent, a generation cost around 0.15€/kWh has been achieved [1]. Around the world, there is a mission to stimulate this green source of energy and it is believed that by 2030, PV will be able to deliver around 9 % of the world's electricity demands. According to an International Energy Agency (IEA) report [2], it is expected that PV will accomplish grid parity in at least 10% of the world by 2020. There was a significant 60 % annual growth in the grid connected PV systems in the span of 2004–2009 [3]. The present article will bring out the status & review of PV technology and the details of PV system standards as suggested by IEA. In the present paper, the main attention has b…