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Interval invariant

As already described for in-service preventive action, the same principle, i.e. integral plant safety must not be affected by changed or extended testing intervals, invariably applies to this case too. The integral approach allows licensees to provide the required evidence and additionally reveals possibilities for optimizing the periodic testing and inspection concept. [Pg.160]

A second constraint is that the relative order of the critical energies at = 0 and fc = I is invariant to the presence or absence of the potential V(4>) [H]-Equation (A.6) shows that the free motion band structure can be folded onto the interval — Consequently, preservation of relative energy orderings at... [Pg.25]

As stated by inequality (2.81) (see also section 4.2 and fig. 30), when the tunneling mass grows, the tunneling regime tends to be adiabatic, and the extremal trajectory approaches the MEP. The transition can be thought of as a one-dimensional tunneling in the vibrationally adiabatic barrier (1.10), and an estimate of and can be obtained on substitution of the parameters of this barrier in the one-dimensional formulae (2.6) and (2.7). The rate constant falls into the interval available for measurements if, as the mass m is increased, the barrier parameters are decreased so that the quantity d(Vom/mn) remains approximately invariant. [Pg.128]

To calculate the profiles and the differential capacitance of the interface numerically we have to choose a differential equation solver. However, the usual packages require that the problem is posed on a finite interval rather than on a semi-infinite interval as in our problem. In principle, we can transform the semi-infinite interval into a finite one, but the price to pay is a loss of translational invariance of the equations and the point mapped from that at infinity is singular, which may pose a problem on the solver. Most of the solvers are designed for initial-value problems while in our case we deal with a boundary-value problem. To circumvent these inconveniences we follow a procedure strongly influenced by the Lie group description. [Pg.827]

Rate of change of observables, 477 Ray in Hilbert space, 427 Rayleigh quotient, 69 Reduction from functional to algebraic form, 97 Regula fold method, 80 Reifien, B., 212 Relative motion of particles, 4 Relative velocity coordinate system and gas coordinate system, 10 Relativistic invariance of quantum electrodynamics, 669 Relativistic particle relation between energy and momentum, 496 Relativistic quantum mechanics, 484 Relaxation interval, 385 method of, 62 oscillations, 383 asymptotic theory, 388 discontinuous theory, 385 Reliability, 284... [Pg.782]

Temperature effects. Consider the so-called typical reaction with a rate constant that doubles over a 10° interval in the vicinity of room temperature. What is its value of A// By what factor will the rate of this reaction increase over a 10° interval near -80 °C Near +600 °C (Assume A// is invariant, an unwarranted assumption over such a very wide temperature range, but sufficient to illustrate the point being made here.)... [Pg.179]

The activation parameters are much less sensitive to temperature changes than are rate or equilibrium constants and usually can be taken as being practically invariant in a narrow temperature interval. The considerations of this paper will be essentially confined to this first approximation with constant A H and AS. (For exceptions, see Section VILA.). [Pg.415]

The lower a graph is more interesting. While initially the Poincar6 phase portrait looks the same as before (point E, inset 2c) an interval of hysteresis is observed. The saddle-node bifurcation of the pericxiic solutions occurs off the invariant circle, and a region of two distinct attractors ensues a stable, quasiperiodic one and a stable periodic one (Point F, inset 2d). The boundary of the basins of attraction of these two attractors is the one-dimensional (for the map) stable manifold of the saddle-type periodic solutions, SA and SB. One side of the unstable manifold will get attract to one attractor (SC to the invariant circle) while the other side will approach die other attractor (SD to die periodic solution). [Pg.289]

As we further change the parameter R, the hysteresis interval ends (the invariant circle stops existing) and the only attractor is the stable periodic frequency locked solution N. Both sides of the unstable manifold of the sad e-type frequency locked solution are attracted to N (Point G, inset 2e). [Pg.289]

The linear time invariant system in Eqs. (9-1) and (9-2) is completely observable if every initial state x(0) can be determined from the output y(t) over a finite time interval. The concept of observability is useful because in a given system, all not of the state variables are accessible for direct measurement. We will need to estimate the unmeasurable state variables from the output in order to construct the control signal. [Pg.172]

In a series of papers (23-26), Polli and colleagues proposed alternative direct curve comparison metrics on this level. In their papers, attention was focused on two aspects (i) are means or medians more suitable for comparison and (ii) how can symmetric confidence intervals be constructed that are invariant when exchanging reference and test In addition, this work was devoted to bioavailability and bioequivalence, i.e., time profiles in vivo, but the conclusions apply likewise to in vitro-release profiles. [Pg.271]

To test the first hypothesis, solutions of 3,5-dinitroanisole and hydroxide ions were flashed and the absorption spectra at different time intervals after excitation were compared. The absorption ( max 400-410 nm) that remains after all time-dependent absorptions have decayed can be shown to be due to 3,5-dinitrophenolate anion, the photosubstitution product of 3,5-dinitroanisole with hydroxide ion. When the absorption band of the 550-570 nm species is subtracted from the spectrum of the solution immediately after the flash, there remains an absorption at 400-410 nm, which can also be ascribed to 3,5-dinitrophenolate anion. The quantity of this photoproduct does not increase during the decay of the 550-570 nm species. Therefore the 550-570 nm species cannot be intermediate in the aromatic photosubstitution reaction of 3,5-dinitroanisole with hydroxide ion to yield 3,5-dinitrophenolate. Repetition of the experiment with a variety of nucleophiles on this and other aromatic compounds yielded invariably the same result nucleophilic aromatic photosubstitution is, in all cases studied, completed within the flash duration (about 20jLts) of our classical flash apparatus. [Pg.256]

ML is the approach most commonly used to fit a distribution of a given type (Madgett 1998 Vose 2000). An advantage of ML estimation is that it is part of a broad statistical framework of likelihood-based statistical methodology, which provides statistical hypothesis tests (likelihood-ratio tests) and confidence intervals (Wald and profile likelihood intervals) as well as point estimates (Meeker and Escobar 1995). MLEs are invariant under parameter transformations (the MLE for some 1-to-l function of a parameter is obtained by applying the function to the untransformed parameter). In most situations of interest to risk assessors, MLEs are consistent and sufficient (a distribution for which sufficient statistics fewer than n do not exist, MLEs or otherwise, is the Weibull distribution, which is not an exponential family). When MLEs are biased, the bias ordinarily disappears asymptotically (as data accumulate). ML may or may not require numerical optimization skills (for optimization of the likelihood function), depending on the distributional model. [Pg.42]

There are invariably rules for how to obtain the multiplying constant for a specific confidence coefficient, but as a good approximation and providing the sample sizes are not too small, using the value 2 for the 95 per cent confidence interval and 2.6 for the 99 per cent confidence interval would get you very close. [Pg.46]

Subsidiary elliptic islands of very small area continue to exist until a last homoclinic tangency occurs at Eht, above which all the trapped orbits of the invariant set are unstable of saddle type. The system is then fully chaotic. According to this scenario, the invariant set may contain quasiperi-odic motion for energies Ea < E < Eht, while the main elliptic island exists only for Ea < E < Ed < Eh,- The interval /, - Ea turns out to be small as compared with the energy interval above Eht, where full chaos has set in and the invariant set is a repeller. [Pg.548]

Electron transfer kinetics from the triplet excited state of TMPD to PA in polystyrene has been monitored by phosphorescence emission decay in ref. 85. The rate constant has been found to be invariant over the temperature interval 77-143 K. Parameters ae and ve calculated from the phosphorescence decay using eqn. (12) were found to be ae = 3.46 A and vc = 104 s 1. [Pg.248]

The smaller peaks in the mass spectra showed random fluctuations in the number of ions formed in the interval between consecutive pulses. The fluctuations were smoothed by performing several experiments at the same conditions and averaging peak heights from spectra taken at the same time interval after the flash. The time dependence of individual peaks was determined by ratioing the peak height of an m/z signal of interest to the peak height at m/z = 20, due to Ne+ from deliberately added Ne. The Ne, of course, does not participate in the reaction and its concentration is time invariant. [Pg.4]


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See also in sourсe #XX -- [ Pg.146 ]




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