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Pi distribution

Using the compositional information obtained from the dual detector UV-RI approach, the molecular weight of the copolymer obtained by this method may be further refined by correcting the Mab at each slice with the pi distribution. The pi distribution may be calculated from... [Pg.246]

The JV(0, 1) random numbers simulated according to the above remark can be used, e.g., for the simulation of nuclear spectra. Nuclear spectrum points (see in O Sect. 9.6) have N pi, pi) distribution. If the p values are calculated from the fitting function and Rj is an N 0, 1) random number, then the formula Y) = Pj + y/plRi defines a random number with N pi, Pi) distribution as required. [Pg.435]

Kheifets and coworkers [107-112] showed the practical importance of the application of the potentials and Eq. (32) for the analysis and characterization of ion-exchange extraction. They also proposed an approach to calculate the Alf(pi distribution potentials from the interface tensions, namely using dependences of Gibbs isotherm type and the Lippmann equation. [Pg.89]

We have a sequence of Poisson observations t/i,..., where each observation j/j has its own mean value /Xj. We have also observed the values (xn,..., Xip) that each of the p predictor variables has for the observation. Let pi come from a Poisson(pi) distribution. The likelihood is... [Pg.204]

The percentages chosen are often denoted as the p85, p50, pi 5 values. Because they each approximately represent one third of the distribution, their discrete probabilities may each be assigned as one third. This approximation is true for a normal (or symmetrical) PDF. [Pg.163]

If there is insufficient data to describe a continuous probability distribution for a variable (as with the area of a field in an earlier example), we may be able to make a subjective estimate of high, medium and low values. If those are chosen using the p85, p50, pi 5 cumulative probabilities described in Section 6.2.2, then the implication is that the three values are equally likely, and therefore each has a probability of occurrence of 1/3. Note that the low and high values are not the minimum and maximum values. [Pg.170]

The microscopic origin of x and hence of Pis the non-unifonnity of the charge distribution in the medium. To lowest order this is given by the dipole moment, which in turn can be related to the dipole moments of the component molecules in the sample. Thus, on a microscopic quantum mechanical level we have the relation... [Pg.225]

Is the temperature 1/0 related to the variance of the momentum distribution as in the classical equipartition theorem It happens that there is no simple generalization of the equipartition theorem of classical statistical mechanics. For the 2N dimensional phase space F = (xi. .. XN,pi,.. -Pn) the ensemble average for a harmonic system is... [Pg.199]

Here, we give here a brief outline of the methods as introduced in Refs. 43, 44, and 47. Suppose that the initial state of the system is tpoili, ,<]n) From ipo, the Wigner phase-space distribution D(qi,..., qn pi,. ..,Pn] is computed. This distribution is used to sample initial positions and momenta, . .., for a classical trajectory simulation of the process of... [Pg.368]

Note that the sums of the squares of the coefficients in a given MO must equal 1 (e.g., 0.3717 + 0.6015 + 0.3717 + 0.6015 = 1.0 for Pi) because each of the AOs represents a probability distribution of finding the electron at a given point in space. The total probability of finding an electron in all space for an MO must be unity, exactly as for its constituent AOs. We now can see that the LCAO approximation is only one of many possibilities to describe the electron density (= probability) for MOs. We do not have to express the electron density as a linear combination of the electron densities of AOs centered at the atoms. We could also... [Pg.378]

The probability of observing a distribution of events requires that event xi (with probability pi) occur, andxa (with probability P2) occtrr, and so on. The probability of observing events, (xi,X2,X3,..., x ), is the simultaneous or sequential probability of observing all events in the distribution occtming once, that is, the product of the individual probabilities ... [Pg.60]

The bimetallic mechanism is illustrated in Fig. 7.13b the bimetallic active center is the distinguishing feature of this mechanism. The precise distribution of halides and alkyls is not spelled out because of the exchanges described by reaction (7.Q). An alkyl bridge is assumed based on observations of other organometallic compounds. The pi coordination of the olefin with the titanium is followed by insertion of the monomer into the bridge to propagate the reaction. [Pg.493]

Steady state pi oblems. In such problems the configuration of the system is to be determined. This solution does not change with time but continues indefinitely in the same pattern, hence the name steady state. Typical chemical engineering examples include steady temperature distributions in heat conduction, equilibrium in chemical reactions, and steady diffusion problems. [Pg.425]

I. Under the null hypothesis, it is assumed that the respective two samples have come from populations with equal proportions pi = po. Under this hypothesis, the sampling distribution of the corresponding Z statistic is known. On the basis of the observed data, if the resultant sample value of Z represents an unusual outcome, that is, if it falls within the critical region, this would cast doubt on the assumption of equal proportions. Therefore, it will have been demonstrated statistically that the population proportions are in fact not equal. The various hypotheses can be stated ... [Pg.499]

Fig. 3.31. Distributions (i)/(Ee) dEe of electron energy (E ) for a low-pressure HF-plasma (suffix pi, Maxwellian with temperature = 80000 K) and an electron beam (suffix eb, simplified to Gaussian shape with 40 eV half-width) (ii) rTx (Ej) ofthe Ej dependent electron impact ionization cross-section for X=Ti... Fig. 3.31. Distributions (i)/(Ee) dEe of electron energy (E ) for a low-pressure HF-plasma (suffix pi, Maxwellian with temperature = 80000 K) and an electron beam (suffix eb, simplified to Gaussian shape with 40 eV half-width) (ii) rTx (Ej) ofthe Ej dependent electron impact ionization cross-section for X=Ti...
We also have studied fluid distribution in the pore H = 6 (Fig. 12(b)) at Ppq = 4.8147 and at two values of Pp, namely at 3.1136 (p cr = 0.4) and at 7.0026 (pqOq = 0.7 Fig. 12(b)). In this pore, we observe layering of the adsorbed fluid at high values of the chemical potential Pp. The maxima of the density profile pi(z) occur at distances that correspond to the diameter of fluid particles. With an increase of the fluid chemical potential, pore filhng takes place primarily at pore walls, but second-order maxima on the density profile pi (z) are also observed. The theory reproduces the computer simulation results quite well. [Pg.336]

In the CHS model only nearest neighbors interact, and the interactions between amphiphiles in the simplest version of the model are neglected. In the case of the oil-water symmetry only two parameters characterize the interactions b is the strength of the water-water (oil-oil) interaction, and c describes the interaction between water (oil) and an amphiphile. The interaction between amphiphiles and ordinary molecules is proportional to a scalar product between the orientation of the amphiphile and the distance between the particles. In Ref. 15 the CHS model is generalized, and M orientations of amphiphiles uniformly distributed over the sphere are considered, with M oo. Every lattice site is occupied either by an oil, water, or surfactant particle in an orientation ujf, there are thus 2 + M microscopic states at every lattice site. The microscopic density of the state i is p.(r) = 1(0) if the site r is (is not) occupied by the state i. We denote the sum and the difference of microscopic oil and water densities by and 2 respectively and the density of surfactant at a point r and an orientation by p (r) = p r,U(). The microscopic densities assume the values = 1,0, = 1,0 and 2 = ill 0- In close-packing case the total density of surfactant ps(r) is related to by p = Ylf Pi = 1 - i i. The Hamiltonian of this model has the following form [15]... [Pg.721]

In pi actice, loads are not necessarily uniformly distributed nor uniaxial, and cross-sectional areas are often variable. Thus it becomes necessary to define the stress at a point as the limiting value of the load per unit area as the area approaches zero. Furthermore, there may be tensile or compressive stresses (O,, O, O ) in each of three orthogonal directions and as many as six shear stresses (t, , T ). The... [Pg.187]

Mutual information, effectively measures the degree to which two probability distributions or, in the context of CA, two sites or blocks - are correlated. Given probability distributions pi and pj and the joint probability distribution py, 1 is defined by ... [Pg.104]

The general problem simplifies considerably in the finite field. F[2. Because circuits are always counted at least twice, their number contributes a factor = 0 (mod 2) we see from equation (5.14), therefore, that the only structural information necessary to obtain Pi x) is that of the parity of disjoint edge distributions. Moreover, since there is no way to distribute disjoint edges among an odd number of vertices, equation (5.13) gives... [Pg.269]

Recall now that the letters in xx are chosen independently with the probability distribution p = (Pi, , > ) and when xx is sent the output is governed by the transition probabilities Pr( i). Thus, each of the terms d( ln,pn) in Eq. (4-123) is an independent random variable with the moment generating function... [Pg.231]

If we assume negative exponential service distribution for each of two channels with parameters and /n2 respectively, the general method of solution proceeds essentially as before except that one is faced with the determination of conditional probabilities P1(1,0, ) and Pi(0,U)i which respectively give the probability that one unit is in the system and it is in service in the first channel at time t and the probability that one unit is in the system and it is in service in the second channel at time t. [Pg.280]

Decision under risk assumes that an a priori probability distribution 0 < 1,2 -1 Pi = 1 is known on the states. One then chooses the... [Pg.315]


See other pages where Pi distribution is mentioned: [Pg.673]    [Pg.42]    [Pg.673]    [Pg.42]    [Pg.1331]    [Pg.110]    [Pg.295]    [Pg.295]    [Pg.178]    [Pg.728]    [Pg.739]    [Pg.746]    [Pg.823]    [Pg.1141]    [Pg.324]    [Pg.33]    [Pg.716]    [Pg.430]    [Pg.336]    [Pg.182]    [Pg.104]    [Pg.307]    [Pg.686]    [Pg.384]    [Pg.968]    [Pg.241]    [Pg.387]    [Pg.139]   
See also in sourсe #XX -- [ Pg.84 ]




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