Reflectance factor

Fig. 13. CIE recommended geometries for illumination and viewing for reflectance-factor measurements (11).

Figure 22.14 Reduction factor as a function of reflection factor K and thickness of crushed rock (gravel) h ...

The reflection factors at the beginning and the end of the parallel stretch follow from Ref. 12 ... 

Estimates were made by Uhlig in the USA. Worner in Australia, and Vernon in the UK, in which the cost of protection and prevention were added to the cost of deterioration due to corrosion. These early estimates were made by individual scientists from cost information from new major industries scaled up to a national level, and were of the order of 1-1.5% of GNP. More detailed estimates were subsequently made by the Committee on Corrosion and Protection (the Hoar Committee) in the UK, and Payer etal. for the National Bureau of Standards in the USA. The later estimates were around 3.5-4% of GNP, the higher figure reflected factors not covered in the earlier surveys, which were, moreover, based on organisations which had probably already taken action to minimise their corrosion costs. Estimates have since been made for other European countries which tend to confirm the higher figure. 

If this happens, then the components are said to be matched to the beam (see Fig. 2). The requirements of Eq. (30) can be converted into surface quality requirements, concerning chiefly the surface figure and the homogeneity of the reflection factor. In terms familiar to astronomers, the surface figure requirements for gw detectors are in the (A/100, A/200) range on about 1000 cm surfaces (see Fig. 2).This requirement is in practice very difficult to fulfill, and new mirror manufacturing methods had to be developed (see Ch. 19). 

In Eqs. (7)—(10), 5(A) is the spectral power distribution of the illuminant, and R A) is the spectral reflectance factor of the object. Jc(A), y(A), and 5(A) are the color-matching functions of the observer. In the usual practice, k is defined so that the tristimulus value, Y, for a perfect reflecting diffusor (the reference for R A)) equals 100. Using the functions proposed by the CIE in 1931, y(A) was made identical to the spectral photopic luminous efficiency function, and consequently its tristimulus value, Y, is a measure of the brightness of objects. The X and Z values describe aspects of color that permit identification with various spectral regions. 

The use of these formulas involves subdividing the visible spectrum into L (at least 16) intervals. The subscript n labels these wavelength intervals. / characterizes the intensity of illumination in interval n, while Rn is the average reflection factor for this interval. The quantities xn, yn, and zn are found in tables (contained in standards) for typical illumination conditions and for an observer with normal vision. If two colored samples are of the same color, their X, Y, and Z values are equal pairwise. If two objects have the same color under a given illumination, this... 

Up to this point we have assumed for simplicity that all raindrops are the same size. A more realistic assumption is that raindrop diameters are distributed according to a continuous function N(D), in which instance the radar reflectivity factor and the rainfall rate are... 

Pigments and coatings may be unambiguously characterized by their spectral reflectance curves q (A) or spectral reflectance factor curves / ( ) (Fig. 3). The reflectance spectrum q (A) or R (A) and hence the color properties can be almost completely derived from physical quantities [1.15] (Fig. 4) ... 

Near the origin of the graph, the film growth rate is proportional to the sulfur incident rate, r(i, S). The slope in this region is approximately equal to the value of the sulfur reflection factor, 8(S), that was obtained from a nonlinear least-square fit of equation 40 to the experimental data. Thus, in the sulfur-limited regime, the deposition rate of ZnS is given by r(d, ZnS) 8(S) r(i, S), in which 8(S) 0.5. 

Similarly, at a high sulfur incident flux, the deposition rate becomes independent of the sulfur flux. Where the curves are horizontal in Figure 13, the deposition rate is 70% of the zinc incident rate, a fraction that is very close to the Zn reflection factor, 8(Zn), that was obtained from the least-square fit. In this Zn-limited regime, the deposition rate is given by r(d, ZnS) 8(Zn) r(i, Zn), in which 8(Zn) 0.7. 

All four hallmarks of quality—appropriateness, accuracy, integrity and transparency—also reflect factors that can be important contributors to the understanding and characterization of uncertainty in a predicted exposure. What kinds of biases or uncertainties might use of particular data contribute to overall uncertainty How much uncertainty do they contribute The quality of data to a large degree determines what approaches, whether qualitative and quantitative, can be taken to characterize uncertainty (see Part 1 of this document). 

The equations are then divided by I or /, respectively, and added. Then the equations K 2k and S = 2s are introduced, and the reflectance or reflectance factor p is the ratio ... 

The basic definition of reflectance, as used in colorimetry, is the ratio of the light flux reflected from a material to the light flux incident on the material. Reflectance involves accounting for all of the visible radiation in the system. This is in contrast to a reflectance factor, which is defined as the ratio of the light flux reflected from a material to light flux reflected from a standard material [23], Material standards of reflectance and transmittance are difficult to obtain. Reflectance, in particular, is difficult since the primary standard of reflectance is the perfect reflecting diffuser,... 

N/A represents the surface coverage by species, fi is the magnitude of the dipole moment perpendicular to the surface, Q is the vibrational frequency, co is the frequency of the incident radiation and G (a) is a reflectivity factor containing the angle of incidence, a, and the dielectric function of the metal, e ... 

For the tortuous and irregular capillaries of porous media, it has been reported theoretically and experimentally that a minimum in the permeability of adsorbates at low pressures is not expected to appear. In our study of n-hexane in activated carbon, however, a minimum was consistently observed for n-hexane at a relative pressure of about 0.03, while benzene and CCI4 show a monotonically increasing behavior of the permeability versus pressure. Such an observation suggests that the existence of the minimum depends on the properties of permeating vapors as well as the porous medium. In this paper a permeation model is presented to describe the minimum with an introduction of a collision-reflection factor. Surface diffusion permeability is found to increase sharply at very low pressure, then decrease modestly with an increase in pressure. As a result, the appearance of a minimum in permeability was found to be controlled by the interplay between Knudsen diffusion and surface diffusion for each adsorbate at low pressures. 

Relaxation measurements require a considerable investment of syectrometer time and in some cases it may be possible to derive basic information about molecular dynamics from the structural ensemble alone. Although regions of disorder can reflect factors other than dynamics, a recent analysis (55) suggests that ill-defined regions in structural ensembles often do reflect slow, large-amplitude motions. Even if relaxation measurements are... 

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