Search results for "equivalent"
showing 10 items of 308 documents
Models and Astrophysical Parameters of High Mass X-ray Binaries
1996
The objective of this work is the High Mass X-ray Binaries. These systems consist of a neutron star orbiting around a star of spectral type OB. According to the luminosity class of the optical companion they split into Supergiant X-ray binaries and Be/X-ray systems. In both systems the high energy radiation is due to the accretion phenomenum, but in the first case the accreted metter comes from the strong stellar wind of the primary and in the second case it comes from the circumstellar envelope surrounding the Be star equator. In this work I concentrate on the optical and infrared bands of the electromagnetic spectrum although a discussion of the X-ray characteristics for some systems is a…
Results from Droxo
2007
AIMS. We study the variability of the Fe 6.4 KeV emission line from the Class I young stellar object Elias 29 in the Rho-Oph cloud. METHODS. We analysed the data from Elias 29 collected by XMM during a nine-day, nearly continuous observation of the Rho-Oph star-forming region (the Deep Rho-Oph X-ray Observation, named Droxo). The data were subdivided into six homogeneous time intervals, and the six resulting spectra were individually analysed. RESULTS. We detect significant variability in the equivalent width of the Fe 6.4 keV emission line from Elias 29. The 6.4 keV line is absent during the first time interval of observation and appears at its maximum strength during the second time inter…
Extracting parameters from semi-log plots of polycrystalline silicon PV modules outdoor I–V data: Double-exponential model revisited
2010
This paper presents a method for extracting physically meaningful parameters from measured I–V curves of PV modules. The 7-parameter double-exponential model is applied in the modeling. The method is based on linear fitting of semi-logarithmic plots. The paper demonstrates a new technique to estimate the series resistance of a module with high accuracy from such plots. As a result, also the reverse saturation current and the quality factor of the diffusion diode can be determined. The method is applied to outdoor I–V data from a test station with three similar, but not identical, polycrystalline-Si modules. The values of the series resistances found with this method deviate somewhat from th…
Relative efficiency revealed: Equations for k<inf>1</inf>&#x2013;k<inf>6</inf> of the PVGIS model
2014
The European PV Geographical Information System (PVGIS) describes module performance in terms of the relative efficiency with respect to Standard Testing Conditions (STC). The efficiency's dependence on irradiance and operating temperature is modeled with a bi-quadratic polynomial with respect to the relative temperature and the logarithm of relative irradiance. In earlier works, the present author derived relations between two model coefficients describing the irradiance dependence at 25°C, k 1 and k 2 , and I–V curve model parameters such as the series resistance RS and the ideality factor n. There was good agreement between the theoretical and fitted values of k 1 , but the fitted values…
Sol-gel produced humidity sensor
1993
Abstract The sol-gel produced polycrystalline Prussian Blue thick films as planar humidity sensors have been investigated by impedance spectroscopy. The equivalent circuit used allows simulation in all the investigated r.h. range (10–100%). The region of changes of sample resistance is about five orders, which is enough for high measuring sensitivity.
RFID passive gas sensor integrating carbon nanotubes
2011
Carbon nanotube (CNT) composites are sensitive to the presence of gases due to their high surface-to-volume ratio and hollow structure that are well suited for gas molecule absorption and storage. Such sensing capability is here integrated with UHF RF identification (RFID) technology to achieve passive and low-cost sensors, remotely readable. CNT film (buckypaper) is used as a localized variable resistive load integrated into a tag antenna, which becomes able to transduce the presence of hazardous gas in the environment, ammonia in this case, into a change of its electromagnetic features. The dynamic range and the hysteresis of the radio sensor are investigated by simulations, equivalent ci…
A fully-automated procedure for measuring the electrical parameters of an induction motor drive with rotor at standstill
2003
The paper presents an automatic procedure to measure at standstill the electrical parameters of an induction motor fed by a PWM voltage source inverter. The proposed procedure executes automatically three tests using only the available PWM inverter control technique to obtain the required motor supply voltages. It allows the measurement of all the T-form circuit electrical parameters starting from the nameplate data as data-entry. It uses only a current sensor and no voltage sensor and process on line the collected data samples with a fast and easy to implement recursive least squares algorithm. Effectiveness of the automated procedure has been proved both by simulation and experimental tes…
Corneal Aberrations, Contrast Sensitivity, and Light Distortion in Orthokeratology Patients: 1-Year Results.
2016
Purpose. To evaluate the corneal higher-order aberrations (HOA), contrast sensitivity function (CSF), and light distortion (LD) in patients undergoing orthokeratology (OK). Methods. Twenty healthy subjects (mean age: 21.40 ± 8 years) with mean spherical equivalent refractive error M = −2.19 ± 0.97 D were evaluated at 1 day, 1 month, and 1 year after starting OK treatment. Monocular LD, photopic monocular CSF, and corneal HOA for 6 mm pupil size were measured. Results. LD showed an increase after the first night (𝑝 0.05). Spherical-like, coma-like, and secondary astigmatism HOA RMS increased significantly (𝑝 ≤ 0.022) from baseline to 1-month visit, remaining unchanged over the follow-up. C…
Il risarcimento per equivalente e in forma specifica.
2014
Il contributo analizza le diverse dottrine che si sono soffermate sull'inquadramento sistematico del risarcimento in forma specifica del danno da inadempimento. Dopo aver qualificato il mezzo di tutela in questione come forma di tutela risarcitoria, l'Autore indaga il rapporto tra il risarcimento in forma specifica e il risarcimento per equivalente e propone la lettura del primo come mezzo di tutela rispondente al medesimo danno del secondo, ma indirizzato al soddisfacimento di un diverso bisogno di tutela. Il che trova rilevanza giuridica nella diversa disciplina apprestata dall'art. 2058 c.c. al risarcimento in forma specifica rispetto al risarcimento per equivalente e può giustificare il…
Il risarcimento in forma specifica e la rilevanza giuridica dell’attività di compensazione del danno.
2013
The author moves from the premise that the quantum of compensation in specific form can be greater than monetary compensation and aims to show that Article 2058 of the Italian Civil Code gives legal relevance to the different way in which damages are compensated through compensation in specific form rather than monetary compensation. This offers the legal justification for the greater economic value of compensation in specific form as it includes both the cost of damage and the cost to compensate it.