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Energy constraints

To do this we must change the j i wavefunctions from normalization per unit energy to normalization per state, i.e. Eq. (20.20). Using the derivative dtT,/dr, = 1/iy5 we may convert the squared wavefunctions 0, 2 from energy to state normalization by multiplying by 1/vj3. Equivalently, a bound 0, wavefunction which is normalized per unit energy has a normalization integral of v2. Since the wavefunction T = is composed of bound wavefunctions normalized per [Pg.423]

If one or more of the channels is open, the wavefunction is a continuum wavefunction, since it extends to r = , and it must be normalized per unit energy. Each of the T, continuum wavefunctions is separately normalized per unit energy, so we simply require for each p solution [Pg.423]

Using the normalization relations of Eqs. (20.21) and (20.24) and the geometric relation between the values we are able to construct properly normalized wavefunctions at any energy. [Pg.423]

As pointed out early in this chapter, nvt is really the phase of the i channel wavefunction as r — . For each bound channel, we have already introduced the constraint W, = - l/2v2 which sets the phase nvt for any energy Wt. If we consider, [Pg.423]


Apart from the energy constraints due to the friction losses, the main reason for limiting the air velocities in ducts is to reduce noise production. Some recommended air velocities are given in Table 9.9. [Pg.787]

Note that the nuclear charge of the erbium atom (M = Er) does not affect the choice of an. One obtains the following energy constraints for the two cluster models ... [Pg.152]

Chemical process data inherently contain some degree of error, and this error may be random or systematic. Thus, the application of data reconciliation techniques allows optimal adjustment of measurement values to satisfy material and energy constraints. It also makes possible the estimation of unmeasured variables. It should be emphasized that, in today s highly competitive world market, resolving even small errors can lead to significant improvements in plant performance and economy. This book attempts to provide a comprehensive statement, analysis, and discussion of the main issues that emerge in the treatment and reconciliation of plant data. [Pg.16]

Multistep or multistage reactions in aqueous solutions are far more complicated than the process depicted above. Nonetheless, the conceptual picture of a saddle point allows one to comprehend the spatial organization and energy constraints influencing chemical reactivity. [Pg.626]

The objective is to minimize the average decoherence rate, R(t), given a bath-coupling spectrum, G( ), by finding the optimal PM, e(t) - under an energy constraint, respectively, given by... [Pg.171]

Figure 4.7 Average modified final decoherence rate R(T), normalized with respect to the unmodulated rate as a function of energy constraint. DD-dash, cyan. Optimal modulation-solid, dark green. Insets optimal modulation Q(t) for different energy constraints, (a) Single-peak resonant dephasing spectrum (inset E = 20). (b) Single-peak off-resonant spectrum (inset E = 50). (c) 1 // spectrum (inset E = 30). (d) Multipeaked spectrum (inset E = 30). (See color plate section for the color representation of this figure.)... Figure 4.7 Average modified final decoherence rate R(T), normalized with respect to the unmodulated rate as a function of energy constraint. DD-dash, cyan. Optimal modulation-solid, dark green. Insets optimal modulation Q(t) for different energy constraints, (a) Single-peak resonant dephasing spectrum (inset E = 20). (b) Single-peak off-resonant spectrum (inset E = 50). (c) 1 // spectrum (inset E = 30). (d) Multipeaked spectrum (inset E = 30). (See color plate section for the color representation of this figure.)...
The plots illustrate the role of the energy constraint E increasing E allows to establish overlap with higher frequency components of the bath spectmm. [Pg.186]

This illustrates the source of the Markovian noise reduction the best solution starts off faster, so as to transfer more of the information while it is still nearly untainted by the bath. Obviously, toward the end it must slow down so as to comply with the energy constraint, thus resulting in total transfer time that is longer than the fastest time for the given energy. [Pg.193]

As far as the controls are concerned, we here consider time-continuous modulation of the system Hamiltonian, which allows for vastly more freedom compared to control that is restricted to stroboscopic pulses as in DD [42, 55, 91]. We do not rely on rapidly changing control fields that are required to approximate stroboscopic a -pulses. These features allow efficient optimization under energy constraint. On the other hand, the generation of a sequence of well-defined pulses may be preferable experimentally. We may choose the pulse timings and/or areas as continuous control parameters and optimize them with respect to a given bath spectrum. Hence, our approach encompasses both pulsed and continuous modulation as special cases. The same approach can also be applied to map out the bath spectrum by measuring the coherence decay rate for a narrow-band modulation centered at different frequencies [117]. [Pg.212]

This repulsive energy constraint implies from eqn (7.64) that the bond energy for the AB alloy must be evaluated for a value of... [Pg.196]

Now we need to determine which points of the surface of Fig. 21.12 correspond to the energy scan of the spectrum of Fig. 21.11. The path along the quantum defect surface is determined by the energy constraint... [Pg.443]

Equations (9.52) shows that the resulting phase tp (co) depends only on the normalized spectral magnitude M( CO) the impulse response duration L. It can be shown that the envelope level of the resulting waveform can be determined, with the application of appropriate energy constraints, from the unnormalized spectrum and duration [Quatieri and McAulay, 1991], Specifically, if the envelope of h(n) is constant over its duration L and zero elsewhere, the envelope constant has the value... [Pg.205]

Variations about a true dynamical path are defined by coordinate displacements 8xa. Velocity displacements Sxa are constrained so as to maintain invariant total energy. This implies modified time values at the displaced points [146], The energy constraint condition is... [Pg.9]

SA = 0 subject to the energy constraint restates the principle of least action. When the external potential function is constant, the definition of ds as a path element implies that the system trajectory is a geodesic in the Riemann space defined by the mass tensor m . This anticipates the profound geometrization of dynamics introduced by Einstein in the general theory of relativity. [Pg.20]


See other pages where Energy constraints is mentioned: [Pg.349]    [Pg.525]    [Pg.976]    [Pg.979]    [Pg.1024]    [Pg.474]    [Pg.440]    [Pg.451]    [Pg.453]    [Pg.455]    [Pg.95]    [Pg.99]    [Pg.287]    [Pg.172]    [Pg.172]    [Pg.172]    [Pg.173]    [Pg.173]    [Pg.174]    [Pg.174]    [Pg.175]    [Pg.175]    [Pg.184]    [Pg.184]    [Pg.187]    [Pg.192]    [Pg.208]    [Pg.423]    [Pg.424]    [Pg.423]    [Pg.423]    [Pg.456]    [Pg.400]    [Pg.10]   
See also in sourсe #XX -- [ Pg.20 ]




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