scholarly journals Extended Source Size Correction Factor in Antenna Gain Measurements

10.5772/8771 ◽  
2010 ◽  
Author(s):  
Aleksey Solovey ◽  
Raj Mittr
Keyword(s):  
Correction Factor ◽  
Source Size ◽  
Antenna Gain ◽  
Extended Source ◽  
Size Correction

On the Interpretation of Solar Radio-Burst Positions in a Scattering Corona

1972 ◽  
Vol 2 (3) ◽  
pp. 148-150 ◽  
Author(s):  
A. C. Riddle
Keyword(s):  
Plasma Level ◽  
Point Source ◽  
Solar Radio ◽  
Plasma Frequency ◽  
Second Harmonic ◽  
Source Size ◽  
Spherically Symmetric ◽  
Extended Source ◽  
True Source ◽  
Solar Bursts

Current observations and theories of solar bursts of types I, II and III suggest that the observed radiation may be emitted at a frequency close to the (fundamental) plasma frequency or its second harmonic. Refraction in a spherically symmetric corona would prevent radiation at the plasma frequency from reaching the observer except when the source is near the centre of the solar disk. However, it is found that fundamental frequency bursts are observed from anywhere on the disk. Recent analyses by Steinberg et al. and Riddle, in which the scattering of the radiation by coronal inhomogeneities was considered (in addition to refraction in an otherwise spherically symmetric corona), show that the radiation can escape from the plasma level and be observed for sources positioned almost anywhere on the disk. In addition, these authors and Fokker showed that a point source of radiation at the plasma frequency, or its harmonic, would be observed as an extended source with dimensions comparable with those observed. One implication was that the true source size is much smaller than the observed size.

Evaluation of Size Correction Factor for Size-specific Dose Estimates (SSDE) Calculation

2016 ◽  
Vol 72 (9) ◽  
pp. 727-734
Author(s):  
Kazufusa Mizonobe ◽  
Yuta Shiraishi ◽  
Satoshi Nakano ◽  
Chiaki Fukuda ◽  
Osamu Asanuma ◽  
...  
Keyword(s):  
Correction Factor ◽  
Size Correction

Climate and size correction in European Union’s Waste Framework Directive and R1 energy efficiency criteria

2018 ◽  
Vol 36 (8) ◽  
pp. 670-688 ◽  
Author(s):  
Kazi Mohammed Rayatul Hoque ◽  
Cagil Ozansoy ◽  
Murat Fahrioglu
Keyword(s):  
European Union ◽  
Energy Efficiency ◽  
Correction Factor ◽  
Correction Factors ◽  
The European Union ◽  
Size Correction ◽  
Recovery Status ◽  
Energy From Waste ◽  
Case Based

This article presents an analysis on the use of the R1 formula to determine the recovery status of some energy from waste plants. Detailed R1 computations are provided to demonstrate the application of R1 guidelines in incineration and gasification facilities. Climate and size correction methods are proposed in consideration of the disadvantage faced by smaller-sized energy from waste plants or those located in warmer regions in meeting the set threshold. A key highlight is the case-based application of climate and size correction factors to three case study plants in scaling the R1 value in consideration of external variants. The proposed size and climate correction factors are compared with the climate correction factor defined in the Waste Framework Directive of the European Union. The application of the proposed correction factors lead to conservative R1 scaling when compared with the application of the Waste Framework Directive climate correction factor. The introduction of the size correction factor addresses an important gap in the current Waste Framework Directive.

Temporal behaviour of a solute cloud in a chemically heterogeneous porous medium

1999 ◽  
Vol 386 ◽  
pp. 77-104 ◽  
Author(s):  
S. ATTINGER ◽  
M. DENTZ ◽  
H. KINZELBACH ◽  
W. KINZELBACH
Keyword(s):  
Porous Medium ◽  
Dispersion Coefficient ◽  
Source Size ◽  
Advective Transport ◽  
Centre Of Mass ◽  
Heterogeneous Porous Medium ◽  
Extended Source ◽  
Temporal Behaviour ◽  
Effective Dispersion ◽  
Spatial Dimensions

In this paper we investigate the temporal behaviour of a solute cloud in a heterogeneous porous medium using a stochastic modelling approach. The behaviour of the plume evolving from a point-like instantaneous injection is characterized by the velocity of its centre-of-mass and by its dispersion as a function of time. In a stochastic approach, these quantities are expressed as appropriate averages over the ensemble of all possible realizations of the medium. We develop a general perturbation approach which allows one to calculate the various quantities in a systematic and unified way. We demonstrate this approach on a simplified aquifer model where only the retardation factor R(x) due to linear instantaneous chemical adsorption varies stochastically in space. We analyse the resulting centre-of-mass velocity and two conceptually different definitions for the dispersion coefficient: the ‘effective’ dispersion coefficient which is derived from the average over the centred second moments of the spatial concentration distributions in every realization, and the ‘ensemble’ dispersion coefficient which follows from the second moment of the averaged concentration distribution. The first quantity characterizes the dispersion in a typical realization of the medium as a function of time, whereas the second one describes the (formal) dispersion properties of the ensemble as a whole. We show that for finite times the two quantities are not equivalent whereas they become identical for t→∞ and spatial dimensions d[ges ]2. The ensemble dispersion coefficient which is usually evaluated in the literature considerably overestimates the dispersion typically found in one given realization of the medium. We derive for the first time explicit analytical expressions for both quantities as functions of time. From these, we identify two relevant time scales separating regimes of qualitatively and quantitatively different temporal behaviour: the shorter of the two scales is set by the advective transport of the solute cloud over one disorder correlation length, whereas the second, much larger one, is related to the dispersive spreading over the same distance. Only for times much larger than this second scale, and spatial dimensions d[ges ]2, do the effective and the ensemble dispersion coefficients become equivalent due to mixing caused by the local transversal dispersion. Finally, the formalism is generalized to an extended source. With growing source size the convergence of the effective dispersion coefficient to the ensemble dispersion coefficient happens faster as the extended source already represents an ensemble of point sources. In the limit of a very large source size, convergence occurs on the time scale of advective transport over one disorder length. We derive explicit results for the temporal behaviour in the different time regimes for both point and extended sources.

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