Figure-of-Merit FoM

To compare the performance among different LC materials, a figure-of-merit (FoM) has been 

In Equation (6.31), K is the elastic constant for a given molecular alignment. For example, K = K i i for a vertical align cell, and K = Kn for a planar (homogeneous) cell. Both K, An, and are temperature dependent. Using Equations (6.16), (6.28), (6.29), and (6.30) for the corresponding temperature dependency, the figure-of-merit is derived as 

The quantity lipkoTc/E in Equation (6.33) is small, and the square root term can be expanded into a power series. Keeping the lowest order terms, we find  

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Another means of comparing the performance of a practical refrigerator is by the use of the figure of merit, FOM, defined as... 

The figure of merit (FOM) for lithium cycling efficiency [24] also is often used to evaluate the cyclability of a lithium cell. The FOM is defined as the number of cycles completed by one atom of lithium before it becomes electrochemically inactive. Equation (2) is derived from the above definition. 

The figures of merit (FOM) of CdTe QDs defined by Re Im are larger than... 

Third-order nonlinear optical properties of CdTe QDs were examined by Z-scan and FWM experiments in the nonresonant wavelength region. We found that the two-photon absorption cross section, a, is as high as 10 GM, although this value decreases with decreasing size. In addition, the nonlinear response is comparable to the pulse width of a fs laser and the figures of merit (FOM = Re Xqd/ Xqd)... 

To have some measure for the goodness of the resulting indexing a Figure of Merit (FOM) is defined ... 

Layer Stacks and Protective Layers, The layer stack of an MO disk consists mainly of an MO layer, a dielectric antireflection layer, and a metallic reflection layer (Fig. 14). The thickness of the antireflection layer as well as that of the MO layer have to be properly chosen to obtain a maximum magnetooptical figure-of-merit (FOM). The FOM can be further increased by using a quadrilayer configuration with dielectric layers on both sides of the MO layer. Practical disks use the generalized configuration 50—120-nm dielectric layer, 25—90-nm MO layer, 17—70-nm dielectric layer (for quadrilayer configuration only), and 15—150-nm reflective layer. 

As an alternative to numerical simulation, we may also use experimental measurements and evaluate the latter with an appropriate figure of merit (FoM). Such a FoM will allow us to compare the performance of different transparent conductors. 

It is, however, certainly useful to include the light scattering property of TCO films in the figure of merit. Furthermore, one should also take into account the exact spectral range where the TCO has to operate (i.e., a differentiation is here necessary between amorphous and microcrystalline silicon solar cells). With this in mind, Fay et al. proposed a new, wavelength-dependent Figure of Merit (FoM(A)) [35] ... 

Fig. 6.49. Wavelength-dependent Figure of Merit FoM(A) defined in (6.7) of LP-CVD ZnO B films deposited with various doping levels, i.e., B2H6/DEZ ratios. The reference value of sheet resistance Rret has been set to (a) 10 Qsq and (b) 5 Qsq...

Secondly, a figure of merit (FOM) can be defined to effectively compare the overall performance of optical sensors as... 

For typical NLO-phores the (ju, ) 6a term is much larger than the p,gl3 term. The molar polarizabilities (113) and (114) were recently used to derive a molecular figure of merit (FOM) for NLO-phores for organic photorefractive (PR) materials with low glass-transition temperature (Wortmann et al., 1996). Rational design of NLO-phores based on this FOM led to organic PR-materials with unprecedented performance (Wtirthner et al., 1997). 

Wp is the weight given to the phase restraint, and / is a square well function with a width equal to the arccosine of the figure of merit (fom(h)) for each reflection. Another possible form of Exray which we call the vector residual does not use the amplitude residual at all but instead simultaneously restrains the real (A) and imaginary (B) parts of the structure factor [24]. It has the form... 

Whatever the indexing method, many plausible cells are usually suggested. It is then useful to apply a figure of merit (FOM) for discriminating the most probable ones and for assessing their reliability. The most adopted FOMs are M20 and F n) proposed by de Wolff and by Smith and Snyder, respectively. M20 is defined as ... 

The numher of trials, the simulation time and the results like analytical solution, mean, variance and figure of merit (fom) are Hsted in Table 3. 

The presented case study and its results (Fig. 2 and Tab. 3) indicate that the probability of occurrence of external explosion events can be successfully assessed by means of the MCS. With the aid of biasing techniques the MCS becomes more efficient, the variance is reduced and the figure of merit (fom) rises. 

Fig. 1.34 Results of phonon-assisted photochemical etching of a glass substrate surface, (a) AFM images of the glass surfaces before and after the etching. Relation between the etching time and the surface roughness Ra is also shown, (b) Incidence pattern of the figure of merit, FoM, before and after the etching...

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