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Reduction of the coefficients

The advantage of the transformed objects over the original ones in data reduction schemes lies in the order induced in the sequence of coefficients. This order is correlated with frequency while in original data the information is more or less uniformly distributed over all the sequence, in transformed object the first few low-frequency coefficients contain the information about the rough contours of the original object and the high-frequency coefficients describe the details. In both Fourier and Hadamard transforms the most important part of the information can be retained after back-transformation with the proper choice of coefficients. [Pg.92]

of course, a matter of discussion which part of the information is the most important one within the same set of objects, different problems will require different part of information to be claimed as being the most important. It is not the purpose of this chapter to discuss this here, we shall accept as the most important part of the information the most prominent feature of the pattern which is contained in the low-frequency coefficients. [Pg.92]

Reshuffling of input data using the bit inversion i3 not necessary in FHT, but is recommended for easier reduction of the measurement space (cut-off of coefficients) [Pg.93]

In the Fourier transform the least significant coefficient is in the middle of the series while more the coefficients are approaching both ends of the series (towards co and cn-i) the greater is their information content. On the other hand, the least important coefficient in the Hadamard transform is the last of the series. [Pg.94]

In order to reconstruct the object from the truncated set of coefficients, the back-transformation (FFT or FHT) must be made on the same number of coefficients as the forward-transformation, i.e. with N coefficients. The only difference between the full and reduced back-transformation is that a certain number of FCs or HCs is set to zero in the latter. [Pg.94]


Inert to almost all chemicals and solvents Reduction of the coefficient of friction Improvement of wear characteristics Resistance to UV radiation and weadiering Improvement in nonstick and release properties Increase of mb resistance... [Pg.166]

Steam is not to be condensed on conventional low-floned tob its high surface tension causes bridging and retention of the condensate and a severe reduction of the coefficient below th u of the rfain tube. [Pg.182]

The effect of the modification of the fibre surface consists in the shift of the sound absorption maximum towards higher frequency range and is accompanied by the decrease of the sound absorption coefficient a. The reduction of the coefficient a is not large. It amounts 2.5 % in the case of composites with pine wood and rapeseed straw Californium. For the samples with beech wood filler the coefficient a remains unaffected after modification. The exception is the composite containing the rapeseed straw Kaszub as a filler that shows the decreasing in the sound absorption of 7%. The reduction of the a coefficient value at the frequency related to the maximum of the sound absorption can be associated with the increase in the density of the composite after modification (Table 1) due to better adhesion between filler particles and polypropylene matrix. The fact implies that the specific acoustic impedance of... [Pg.200]

The reduction of the coefficient of variation of 54 %. was a promising result and indicated a potential for improving the stability of alumina as a raw material. Based on this result a go ahead for an installation in a full scale silo battery consisting of two silos of 6000 tons was given. [Pg.629]

The most important benefits expected from the nanosilica reinforcement are the following (i) lower viscosity of the resin formulation compared to common reinforcing fillers and a complete suppression of sedimentation, (ii) increased fracture toughness, impact strength, and modulus, (iii) improved scratch- and abrasion-resistance, (iv) reduced shrinkage upon curing and reduction of the coefficient of thermal expansion, (v) improved dielectric properties, (vi) improve-... [Pg.93]

The expression exp(-cxx) describes the reduction of the wave amplitude in absorbing materials. The damping coefficient a can be split into an absorption coefficient Oa and the scattering coefficient Oj. [Pg.866]

Multidimensionality may also manifest itself in the rate coefficient as a consequence of anisotropy of the friction coefficient [M]- Weak friction transverse to the minimum energy reaction path causes a significant reduction of the effective friction and leads to a much weaker dependence of the rate constant on solvent viscosity. These conclusions based on two-dimensional models also have been shown to hold for the general multidimensional case [M, 59, and 61]. [Pg.851]

The most important feature of the Fourier analysis is the reduction of the multicoUi-nearity and ike dimension of ike original specira. However, ihe Fourier coefficients hear no. simple relationship to individual features of the spectrum so that it will not he clear what information is being used in calibration."... [Pg.216]

The dependency of liquid volume on pressure may be expressed in terms of the coefficient of compressibility. The coefficient is constant over a wide range of pressures for a particular material, but is different for each substance and for the solid and liquid states of the same material. For liquids, volume decreases linearly with pressure. For gases volume is observed to be inversely proportional to pressure/. If water in its liquid state is subjected to a pressure change from 1 to 2 atm, then less than a 10 % reduction in volume occurs (the compressibility coefficient is very small). However, when the same pressure differential is applied to water vapor, a volume reduction in excess of 2 occurs. [Pg.72]

But then is the characteristic polynomial of A, and its coefficients are the elements of / and can be found by solving Eq. (2-11). This is essentially the method of Krylov, who chose, in particular, a vector et (usually ej) for vx. Several methods of reduction of the matrix A can be derived from applying particular methods of inverting or factoring V at the same time that the successive columns of V are being developed. Note first that if... [Pg.73]

P the total pressure, aHj the mole fraction of hydrogen in the gas phase, and vHj the stoichiometric coefficient of hydrogen. It is assumed that the hydrogen concentration at the catalyst surface is in equilibrium with the hydrogen concentration in the liquid and is related to this through a Freundlich isotherm with the exponent a. The quantity Hj is related to co by stoichiometry, and Eg and Ag are related to - co because the reaction is accompanied by reduction of the gas-phase volume. The corresponding relationships are introduced into Eqs. (7)-(9), and these equations are solved by analog computation. [Pg.85]

Wall-to-bed heat-transfer coefficients were also measured by Viswanathan et al. (V6). The bed diameter was 2 in. and the media used were air, water, and quartz particles of 0.649- and 0.928-mm mean diameter. All experiments were carried out with constant bed height, whereas the amount of solid particles as well as the gas and liquid flow rates were varied. The results are presented in that paper as plots of heat-transfer coefficient versus the ratio between mass flow rate of gas and mass flow rate of liquid. The heat-transfer coefficient increased sharply to a maximum value, which was reached for relatively low gas-liquid ratios, and further increase of the ratio led to a reduction of the heat-transfer coefficient. It was also observed that the maximum value of the heat-transfer coefficient depends on the amount of solid particles in the column. Thus, for 0.928-mm particles, the maximum value of the heat-transfer coefficient obtained in experiments with 750-gm solids was approximately 40% higher than those obtained in experiments with 250- and 1250-gm solids. [Pg.129]

Figure 6. Reduction of the overall heat transfer coefficient attributable to particle swelling in an acrylic precipitation polymer (43)... Figure 6. Reduction of the overall heat transfer coefficient attributable to particle swelling in an acrylic precipitation polymer (43)...
Other ideas are connected with reduction of the original second-order difference equation (9) to three first-order ones, which may be, generally speaking, nonlinear. First of all, the recurrence relation with indeterminate coefficients a,- and f3i is supposed to be valid ... [Pg.9]

FIG. 13 Reduction of the relative permeability coefficient is dependent on the clay platelet aspect ratio in the system of polyimide-clay hybrid with water vapor as the permeate. Each hybrid contains 2 wt% clay. The aspect ratios for hectorite, saponite, montmorillonite, and synthetic mica are 46, 165, 218, and 1230, respectively. (From Ref. 71.)... [Pg.666]

With a view to determining the equilibrium constant for the isomerisation, the rates of reduction of an equilibrium mixture of cis- and rra/i5-Co(NH3)4(OH2)N3 with Fe have been measured by Haim S . At Fe concentrations above 1.5 X 10 M the reaction with Fe is too rapid for equilibrium to be established between cis and trans isomers, and two rates are observed. For Fe concentrations below 1 X lO M, however, equilibrium between cis and trans forms is maintained and only one rate is observed. Detailed analysis of the rate data yields the individual rate coefficients for the reduction of the trans and cis isomers by Fe (24 l.mole sec and 0.355 l.mole .sec ) as well as the rate coefficient and equilibrium constant for the cw to trans isomerisation (1.42 x 10 sec and 0.22, respectively). All these results apply at perchlorate concentrations of 0.50 M and at 25 °C. Rate coefficients for the reduction of various azidoammine-cobalt(lll) complexes are collected in Table 12. Haim discusses the implications of these results on the basis that all these systems make use of azide bridges. The effect of substitution in Co(III) by a non-bridging ligand is remarkable in terms of reactivity towards Fe . The order of reactivity, trans-Co(NH3)4(OH2)N3 + > rra/is-Co(NH3)4(N3)2" > Co(NH3)sN3 +, is at va-... [Pg.196]

The apparent first-order rate coefficient obtained using excess oxidant increased exponentially with increase in acidity in the range 5 N < [H30" ] < 12 N. The reaction is first-order with respect to added manganous ions (k increasing sharply), but the activation energy (11.0 kcal.mole ) remains unchanged. At appreciable catalyst concentrations the reaction becomes almost zero-order with respect to bromide ion. The mechanism appears to be a slow oxidation of Mn(II) to Mn(III) followed by a rapid reduction of the latter by bromide. This reaction is considered further in the section on Mn(II)-catalysis of chromic acid oxidations (p. 327). [Pg.282]

Owing to its low water solubility and high octanol/water partition coefficients, dinitroaniline herbicides adsorb and bind to soil macromolecules and show minimal leaching potential. Dinitroanilines herbicides show good soil residue activities with soil half-lives ranging from 30 days for benfluralin and oryzalin to 6-7 months for trifluralin. Al-Dealkylation (aerobic conditions) and reduction of the nitro group to an amino moiety (anaerobic conditions) have been reported as major soil degradation pathways. [Pg.389]


See other pages where Reduction of the coefficients is mentioned: [Pg.92]    [Pg.262]    [Pg.626]    [Pg.28]    [Pg.177]    [Pg.179]    [Pg.414]    [Pg.93]    [Pg.2779]    [Pg.294]    [Pg.92]    [Pg.262]    [Pg.626]    [Pg.28]    [Pg.177]    [Pg.179]    [Pg.414]    [Pg.93]    [Pg.2779]    [Pg.294]    [Pg.362]    [Pg.119]    [Pg.1339]    [Pg.198]    [Pg.118]    [Pg.1006]    [Pg.205]    [Pg.189]    [Pg.102]    [Pg.45]    [Pg.261]    [Pg.172]    [Pg.1006]    [Pg.28]    [Pg.330]    [Pg.788]    [Pg.793]    [Pg.180]    [Pg.12]    [Pg.345]    [Pg.165]   


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