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Convexity estimation

The left-hand side of this inequality can be estimated from above by using the convexity of J2. Then we derive the obtained inequality by A and pass to the limit as A —> 0. The resulting relation coincides with (1.76). Theorem 1.4 is completely proved. [Pg.28]

The dimer chains of Ca -ATPase can also be observed by freeze-fracture electron microscopy [119,165,166,172-174], forming regular arrays of oblique parallel ridges on the concave P fracture faces of the membrane, with complementary grooves or furrows on the convex E fracture faces. Resolution of the surface projections of individual Ca -ATPase molecules within the crystalline arrays has also been achieved on freeze-dried rotary shadowed preparations of vanadate treated rabbit sarcoplasmic reticulum [163,166,173,175]. The unit cell dimensions derived from these preparations are a = 6.5 nm b = 10.7 nm and 7 = 85.5° [175], in reasonable agreement with earlier estimates on negatively stained preparations [88]. [Pg.71]

Remark 2.1. The estimate above for the rate of decay at infinity holds for an arbitrary system of N bodies (w, du>i, 1 < i < N) confined to a bounded convex domain with a smooth boundary dQ. Indeed let... [Pg.30]

A drawback of the gamut-constraint method is that it may fail to find an estimate of the illuminant. This may happen if the resulting intersected convex hull A4n is the empty set. Therefore, care must be taken not to produce an empty intersection. There are several ways to address this problem. One possibility would be to iteratively compute the intersection by considering all of the vertices of the observed gamut in turn. If, as a result of the intersection, the intersected hull should become empty, the vertex is discarded and we continue with the last nonempty hull. Another possibility would be to increase the size of the two convex hulls that are about to be intersected. If the intersection should become empty, the size of both hulls is increased such that the intersection is nonempty. A simple implementation would be to scale each of the two convex hulls by a certain amount. If the intersection is still empty, we again increase the size of both hulls by a small amount. [Pg.120]

Discrete and continuum models of transfer of molecules over various sorption sites of a microheterogeneous membrane were considered for systems with weak intermolecular interactions and membranes with constant composition and structure. An equation for estimating size effects on permeability coefficient II of microheterogeneous membranes was derived [188], and the possibility of applying the continuum model to calculate the n value in thin films of thickness L is numerically analyzed. The effect of the composition and structure of a uniformly microheterogeneous membrane on the permeability coefficients II was studied. The dependence of n on the composition is a convex function if the migration between different sorption sites proceeds more quickly than between identical sites and a concave one in the opposite case [189],... [Pg.416]

There has been some discussion as to whether CD can distinguish parallel from antiparallel p sheets. As stable, well-defined model compounds are lacking, the spectra available have been derived from secondary structure deconvolutions (see below). Overall, the ability of CD to provide adequate estimates of both parallel and antiparallel p sheet contents is still an ongoing question. Johnson and co-workers were the first to derive basis spectra which corresponded to both parallel and antiparallel p sheet structures in globular proteins using the singular value deconvolution method [11, 12, 51-53], However, the basis spectra were significantly different from spectra reported for model sleet structures. Recently, Perczel et al. [54] employed another approach, convex curve analysis, to obtain improved p sheet baas spectra. The major improvement was to include more p sheet proteins into the data base. [Pg.179]

The Type II isotherm is concave to the plp° axis, then almost linear and finally convex to the p/p° axis. It indicates the formation of an adsorbed layer whose thickness increases progressively with increasing relative pressure until p/p°— 1. When the equilibrium pressure equals the saturation vapour pressure, the adsorbed layer becomes a bulk liquid or solid. If the knee of the isotherm is sharp, the uptake at Point B - the beginning of the middle quasilinear section — is usually considered to represent the completion of the monomolecular layer (monolayer) and the beginning of the formation of the muldmolecular layer (multilayer). The ordinate of Point B gives an estimation of the amount of adsorbate required to cover the unit mass of solid... [Pg.19]

The remaining curves on the psychrometric chart are almost vertical and convex to the left, with labeled values (on Figure 8.4-1) of -0.05, -0.1, -0.2, and so on. (The units of these numbers are kJ/kg DA). These curves are used to determine the enthalpy of humid air that is not saturated. The procedure is as follows (a) locate the point on the chart corresponding to air at its specified condition (b) interpolate to estimate the enthalpy deviation at this point ... [Pg.388]

Alternatively, the duration of hydrothermal convection in the oceanic crust can be estimated by mapping the distribution of nonlinear temperature profiles taken during heat-flow measurements as a function of oceanic-crustal age. Purely conductive heat loss (i.e., no hydrothermal circulation) results in linear temperature profiles in sediments, while convective heat loss results in concave or convex profiles, depending on whether the water penetrates into or comes out of the sediments. [Pg.1779]

This method, however, has some limitations. First, when the surface is dilated, the information on the contour detail might be lost, as illustrated in Fig. 2, and hence F( ) might not be representative of the actual volume. Second, the surface of the object has to be convex for the laser source to access. If the surface were too rough or concave, it would be inaccessible and become lost in the image reconstruction. Third, the estimated Ds depends on the spatial (x,y) and depth of view that govern resolution. Analyzed surface not within the depth of view of the optics would not be taken into calculation, resulting in an inaccurate Ds-... [Pg.1792]

If we can assume that the WSS surface between the initial estimate and the global minimum is convex, a Taylor series expansion leads to the Gauss-Newton approximation for a step closer to the minimum. Thus, the next point on the surface can be calculated as in Eq. (20) ... [Pg.2764]


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See also in sourсe #XX -- [ Pg.640 ]




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