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Equation, discontinuous

In a first step this control algorithem was tested by a simulation of the whole circuittaking into consideration reactor behavior,reaction rate equation. discontinuous analysis. analytical errors and control-strategy. [Pg.259]

Secondly, the linearized inverse problem is, as well as known, ill-posed because it involves the solution of a Fredholm integral equation of the first kind. The solution must be regularized to yield a stable and physically plausible solution. In this apphcation, the classical smoothness constraint on the solution [8], does not allow to recover the discontinuities of the original object function. In our case, we have considered notches at the smface of the half-space conductive media. So, notche shapes involve abrupt contours. This strong local correlation between pixels in each layer of the half conductive media suggests to represent the contrast function (the object function) by a piecewise continuous function. According to previous works that we have aheady presented [14], we 2584... [Pg.326]

On compression, a gaseous phase may condense to a liquid-expanded, L phase via a first-order transition. This transition is difficult to study experimentally because of the small film pressures involved and the need to avoid any impurities [76,193]. There is ample evidence that the transition is clearly first-order there are discontinuities in v-a plots, a latent heat of vaporization associated with the transition and two coexisting phases can be seen. Also, fluctuations in the surface potential [194] in the two phase region indicate two-phase coexistence. The general situation is reminiscent of three-dimensional vapor-liquid condensation and can be treated by the two-dimensional van der Waals equation (Eq. Ill-104) [195] or statistical mechanical models [191]. [Pg.132]

The virial pressure equation for hard spheres has a simple fomr detemiined by the density p, the hard sphere diameter a and the distribution fimction at contact g(c+). The derivative of the hard sphere potential is discontinuous at r = o, and... [Pg.473]

Flere [ ] denotes the discontinuity in across tlie interface. Equation (A3.3.71). equation (A3.3.74), equation (A3.3.76) and equation (A3.3.77) together detemiine the interface motion. [Pg.748]

An alternative way to eliminate discontinuities in the energy and force equations is to use a switching function. A switching function is a polynomial ftmction of the distance by which the potential energy function is multiplied. Thus the switched potential o (r) is related to the true potential t> r) by v r) = v(r)S(r). Some switching functions are applied to the entire range of the potential up to the cutoff point. One such function is ... [Pg.345]

In conjunction with the discrete penalty schemes elements belonging to the Crouzeix-Raviart group arc usually used. As explained in Chapter 2, these elements generate discontinuous pressure variation across the inter-element boundaries in a mesh and, hence, the required matrix inversion in the working equations of this seheme can be carried out at the elemental level with minimum computational cost. [Pg.125]

Fracture markings can be used to locate the failure origin, which is the discontinuity or flaw that caused the appHed stress to be amplified locally. Once the failure origin has been located, the failure stress can be estimated using the flaw size and equation 6, or the distances to the boundaries of the mirror, mist, and hackle (whichever is most evident) and the foUowing relation (63)... [Pg.327]

The input is continued until 200 lb mol of A have been added, which is for 50 min. Eq. (3) is integrated for this time interval. After input is discontinued the rate equation is... [Pg.710]

This equation was derived for a two-dimensional system, where the areal density, p, of the snow was used. It applies equally to a three-dimensional system, where the discontinuity is a plane instead of a line, and p is the volume density. [Pg.9]

Conservation equations Expressions that equate the mass, momentum, and energy across a steady wave or shock discontinuity ((2.1)-(2.3)). Also known as the jump conditions or the Rankine-Hugoniot relations. [Pg.40]

In summary, equation (13) accurately describes longitudinal dispersion in the stationary phase of capillary columns, but it will only be significant compared with other dispersion mechanisms in LC capillary columns, should they ever become generally practical and available. Dispersion due to longitudinal diffusion in the stationary phase in packed columns is not significant due to the discontinuous nature of the stationary phase and, compared to other dispersion processes, can be ignored in practice. [Pg.250]

The flow field in front of an expanding piston is characterized by a leading gas-dynamic discontinuity, namely, a shock followed by a monotonic increase in gas-dynamic variables toward the piston. If both shock and piston are regarded as boundary conditions, the intermediate flow field may be treated as isentropic. Therefore, the gas dynamics can be described by only two dependent variables. Moreover, the assumption of similarity reduces the number of independent variables to one, which makes it possible to recast the conservation equations for mass and momentum into a set of two simultaneous ordinary differential equations ... [Pg.98]

As a consequence of implicit mass conservation, the gas-dynamic conservation equations, expressed in Lagrangean form, can describe contact discontinuities. To prevent oscillating behavior in places where shock phenomena are resolved in the... [Pg.104]

A drawback of the Lagrangean artificial-viscosity method is that, if sufficient artificial viscosity is added to produce an oscillation-free distribution, the solution becomes fairly inaccurate because wave amplitudes are damped, and sharp discontinuities are smeared over an increasing number of grid points during computation. To overcome these deficiencies a variety of new methods have been developed since 1970. Flux-corrected transport (FCT) is a popular exponent in this area of development in computational fluid dynamics. FCT is generally applicable to finite difference schemes to solve continuity equations, and, according to Boris and Book (1976), its principles may be represented as follows. [Pg.105]

Initial shock-wave overpressure can be determined from a one-dimensional technique. It consists of using conservation equations for discontinuities through the shock and isentropic flow equations through the rarefaction waves, then matching pressure and flow velocity at the contact surface. This procedure is outlined in Liepmatm and Roshko (1967) for the case of a bursting membrane contained in a shock tube. From this analysis, the initial overpressure at the shock front can be calculated with Eq. (6.3.22). This pressure is not only coupled to the pressure in the sphere, but is also related to the speed of sound and the ratio of specific heats. [Pg.189]

The principal cathodic reaction on the upper surface of the membrane is the reduction of Cu " that is formed by the reaction of Cu with dissolved oxygen in the water these Cu ions are provided partly from the diffusion through the pores in the oxide membrane from within the pit and partly from those produced by cathodic reduction (equation 1.154). Lucey s theory thus rejects the conventional large cathode small anode relationship that is invoked to explain localised attack, and this concept of an electronically conducting membrane has also been used by Evans to explain localised attack on steel due to a discontinuous film of magnetite. [Pg.187]

This property of the degenerate equation of exhibiting a nonuniform convergence of for t 0 means that for the degenerate equation the velocity jumps quasi-discontinuously to its proper value, so that only one constant of integration is sufficient, in spite of the fact that the state of rest is specified by two initial conditions, x0 = x0 = 0. [Pg.386]

This somewhat subtle point shows that there are variables that are capable of exhibiting quasi-discontinuous features in the case of the degenerescent differential equation. In the above case this variable was the velocity x(t), there are some other cases in which it may be x(t). [Pg.386]

The essential feature of the discontinuous theory appears when a trajectory reaches a point for which T xc,ye) => 0 we call this point (xe>Ve) a critical point In such a case the differential equations (6-194) lose their meaning as x and y become infinite, exhibiting thus a discontinuous jump. [Pg.387]

From the standpoint of the classical (analytical) theory with which we were concerned in this review, the situation is obviously absurd since each of these two equations is linear and of a dissipative type (since h > 0) trajectories of both of these equations are convergent spirals tending to approach a stable focus. However, if one carries out a simple analysis (see Reference 6, p. 608), one finds that change of equations for = 0, results in the change of the focus in a quasi-discontinuous manner, so that the trajectory can still be closed owing to the existence of two nonanalytic points on the -axis. If, however, the trajectory is closed, this means that there exists a stationary oscillation and in such a case the system (6-197) is nonlinear, although, from the standpoint of the differential equations, it is linear everywhere except at the two points at which the analyticity is lost. [Pg.389]

Particles spin Vz, 517 Dirac equation, 517 spin 1, mass 0,547 spin zero, 498 Partition function, 471 grand, 476 Parzen, E., 119,168 Pauli spin matrices, 730 PavM, W., 520,539,562,664 Payoff, 308 function, 309 discontinuous, 310 matrix, 309... [Pg.780]


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See also in sourсe #XX -- [ Pg.41 ]




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Discontinuous

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