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Minimum function

Here, the minimum function returns the smaller of the arguments. According to this rule a new path is accepted, if a random number chosen from a uniform distribution in the interval [0,1] is smaller than m z ) j 2T). To implement... [Pg.256]

Microwave rotational spectra of intramolecularly hydrogen-bonded species in the gas phase have been analysed to provide details of the symmetry of the species and thereby to determine whether the potential energy is best represented by a single- or double-minimum function. The spectrum of 6-hydroxy-2-formylfulvene is compatible with a structure of C2v symmetry in which the proton is centred in the hydrogen bond [15] or with a rapidly... [Pg.133]

Bohr. Of course, in the molecular plane itself, all rr-MO s have the value zero. The contours of each MO are obtained by dividing the difference between the maximum and the minimum function value into equal increments. In all cases, the function values are about 0.239 Bohr"3/2 for the maximum contour, about -0.072 Bohr 3/2 for the minimum contour, and about 0.016 Bohr 3/i for the increment. [Pg.58]

Implication in IMVL. The second major difference is in how the value of the consequent of an implication is calculated. The method is multiplicative as compared to the minimum function of LT MVL. The formulae involved are shown below where TV (A) = TV(A) iff TV(A) > 0 otherwise 0. [Pg.201]

The P clusters of nitrogenase. The enzyme nitrogenase consists of two proteins the Fe protein (m.w. 55,000), which contains a single 4Fe-4S center, and the more complex MoFe protein (m.w. 220,000) (48,49). The minimum functional unit of the latter appears to be the half molecule, an asymmetric dimer containing 1 Mo, 14-16 Fe, and 16-18 sulfides. Application of a vast array of spectroscopic methods to the MoFe protein in a variety of oxidation states has led to the conclusion that it contains two types of metal-sulfur cluster in a 2 1 ratio unusual Fe S units termed P clusters, and the protein-bound form of the FeMo-cofactor (50). [Pg.274]

The search for the minimum function E in (5.4), according to methods described in Bellman and Roth (1966), can be reduced to a problem of dynamic programming. Suppose that coefficients are functions of time. [Pg.305]

The minimum function gives the minimum value of (pXj/t>jMj) for all the reactants j taking part in this reaction. Finally, the reaction rate R is calculated as the product of the molar stoichiometry Uj of species i and the minimum of Rki and Rmi ... [Pg.796]

Exposure models relate the concentration of a substance in soil to the potential for exposure or uptake in a human or ecological receptor. They can be described and calibrated on the basis of land use (Figure 5.3), but we recommend that there is a base set of data that would be used in calibrating minimum function in any land use. Calculated exposure differed substantially among models in a comparison of 7... [Pg.110]

Some important considerations have to be taken into account in order to efficiently use the SSM and all other gradient methods with rapid displacement towards a minimum function value [3.64] (i) the good selection of the base point (ii) the modification of the parameters dimension from one step to another (iii) the complexity of the process surface response (iv) the number of constraints imposed on the parameters. In some cases we can couple the minimization of the function with the constraint relations in a more complex function, which will be analyzed again. In this case, the problem is similar to the Lagrange problem but it is much more complex. [Pg.152]

The emplo5unent of robust aromatic ligand architectures able to introduce the same kind of reactivity in a reversible manner is of course much more desirable. For this purpose, biological redox cofactors such as quinones, porphyrins, flavins, and their functional analogues in biomimetic chemistry contain a built-in butadiene-t5rpe moiety as part of their n-electron system, which can be considered as a minimum functional motif for assisting the reversible uptake of two electrons and two protons. This... [Pg.262]

Let us consider Fig. 3 in which a double-minimum function represents the Born-Oppenheimer potential for the electronic ground-state of ammonia. This is an energy versus internal inversion coordination diagram. Every value of the inversion coordinate corresponds to a particular nuclear framework for ammonia. The two minima, for example, correspond to pyramidal structures, whereas the maximum corresponds to a planar... [Pg.98]

In a minimum-function map, the origin of the Patterson map is put in turn on each of the known symmetry-related positions of a heavy atom that has already been located from a Patterson map. On each superposition of the origin of the Patterson map onto the various symmetry-related heavy-atom positions, the lowest value at each superimposed grid point in the pairs of maps is recorded. This superposition process is repeated until the structure is revealed. In this way the lighter atoms can be located. The method is an alternative to the heavy-atom method just described and has proved useful in many cases. [Pg.312]

Minimum function Analysis of the Patterson map by setting its origin in turn on the known positions of certain atoms, and then recording the minimum value for all of these superpositions. The resulting three-dimensional map should contain an indication of the atomic arrangement. [Pg.334]

M. A. Estermann and W. I. F. David, Patterson methods in powder diffraction maximum entropy and symmetry minimum function techniques, in Structure determination from powder diffraction data. rUCr monographs on crystallography 13. W. I. F. David, K. Shankland,... [Pg.591]

The spin-related section mle can be proved by elastic neutron scattering measurements. In order to establish the specific fingerprint of the spin correlation, the scattering functions for the linear harmonic oscillator, for the double-well minimum function, and for pairs of coupled oscillators have been calculated in Ref. 119. [Pg.378]


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See also in sourсe #XX -- [ Pg.334 ]




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Density functional theory calculating minimum energy

Excitation functions minima

Global minimum function

Maximum and minimum values of a function

Minimum detectable mass function

Minimum in Their S(T) function

Minimum of function

Minimum of functions in one dimension

Minimum stored energy functions

Minimum value of a function

Minimum-distance distribution function

Minimum-distance distribution function MDDF)

Optimizing General Functions Finding Minima

The minimum functional unit

Vibrational potential functions with more than one minimum

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