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Generic iteration

The criterion to calculate the value of these variables is a variant of the orthogonal collocation method. In a generic iteration, knowing the values of these variables, it is possible to build N piecewise Hermite polynomials. Using these polynomials, it is possible to calculate the value of the N variables and their first and second derivatives in the internal points for each element These internal points are the Gauss quadrature points and they are 2 for a third-order, 3 for the fourth-order, 4 for the fifth-order, and 5 for the sixth-order polynomials. [Pg.256]

In a generic iteration, a feasible point is known together with the active variable bounds and inequality constraints. If the point is anything other than solution, a search direction must be determined to improve the objective function. In this search, all the active inequality constraints are treated as equality constraints, whereas the active bounds are used to simplify the problem. [Pg.413]

The most appealing alternative was proposed by Fletcher (1987). Fletcher demonstrated that if we know the exact values of the Lagrange parameters, Xj, it should be possible to use a merit function that avoids the Maratos effect. This option will be considered in Section 12.2.4. Unfortunately, the exact values of 2 are unknowns in a generic iteration and only their estimations are available therefore, the Maratos effect could also arise with such a function. [Pg.429]

In a generic iteration, Xj used in the function (12.23), can be quite different from the exact ones, especially when many constraints are present. Thus, the Maratos effect could occur. [Pg.432]

Intermlttency Manneville [mann80] showed that for the special case of a generic intermittency threshold in which the tangent point lies at the endpoint of the interval (in the case of a one dimensional iterative map of an interval to itself), the resulting chaotic dynamics has a power spectrum S f) 1/ (/(log/) ) for low /. Miracky, et. al. were able to modify the map to obtain an exact 1// behavior [mirack87]. Because the result depends on the fine-tuning of an external parameter, however, it does not so mucdi explain the generic appearance of flicker noise phenomena as beg the obvious question, why do systems typically sit at whatever... [Pg.442]

Equation (9.53) for the desired molecular field is nonlinear, typically solved iteratively. For this molecular-field approach to become practical, an alternative to this nonlinear iterative calculation is required. A natural idea is that a useful approximation to this molecular field might be extracted from simulations with available generic force fields. Then with a satisfactory molecular field in hand, the more ambitious quasichemical evaluation of the free energy can be addressed, presumably treating the actual binding interactions with chemical methods specifically. This is work currently in progress. [Pg.342]

Its design versatility, as generic dendrons may be prepared to be used later as building blocks in conjunction with other reactive molecules, or coupled to a multifunctional core to afford functional dendrimers, dendritic-linear hybrids, dendronized polymers, etc. This may be a particularly significant advantage if the coupled reactive or core molecule is itself sensitive to the reaction conditions used in the multiple steps of the iterative synthesis of a dendrimer. [Pg.570]

D. Generic Problems with Iterative Multiple Sequence Methods. 154... [Pg.137]

A generic problem with profile methods that iterate is the possibility of profile wander (also called matrix migration). This occurs when sequences found in early rounds of the iterative search are not found in later rounds of the search. This problem affects both PSI-BLAST and HMMER. This means that one should record all the intermediate steps so that these lost members of the family can be recovered. Profile wander only becomes a problem for large protein families, and therefore the cause of the profile wander may be related to the limits of modeling using profiles. [Pg.155]

Our failure risk analysis and opportunity method and iterative software tool, as part of our New Product Process Innovation (NPPI) Tool Library, promotes systematic collaboration and team-oriented engineering thinking when a new pharmaceutical manufacturing system process and/or product are developed. (We call it opportunity method too, since most risks, if not all, offer new opportunities for innovation.) It is based on our generic process failure risk analysis method that could be apphed to literally any process that involves risk—and innovation is a very risky process. [Pg.183]

Finite difference — Finite difference is an iterative numerical procedure that has been used to quantify current-voltage-time relationships for numerous electrochemical systems whose analyses have resisted analytic solution [i]. There are two generic classes of finite difference analysis 1. explicit finite difference (EFD), where a new set of parameters at t + At is computed based on the known values of the relevant parameters at t and 2. implicit finite difference (IFD), where a new set of parameters at t + At is computed based on the known values of the relevant parameters at t and on the yet-to-be-determined values at t + At. EFD is simple to encode and adequate for the solution of many problems of interest. IFD is somewhat more complicated to encode but the resulting codes are dramatically more efficient and more accurate - IFD is particularly applicable to the solution of stiff problems which involve a wide dynamic range of space scales and/or time scales. [Pg.273]

Iterative calculations using the implicit Eqs. (1.139) start with an initial value of Zvap close to one and an initial value of Ziiq cl°se 10 zero. Once the value of compressibility is obtained, then volume is obtained from V = ZRT/P. Table 1.3 lists the parameters for the generic equation of state. [Pg.25]

A note of caution, however, is in order now. While it is indeed true that for a generic r in the chaotic regime the length of an analytical formula for the prediction of Xn from xq grows exponentially in n, exceptions do occur at special values of r. For r = 4, e.g., a clever argument by Ulam and von Neumann (1947) shows that the iterates of (1.2.1) can be written explicitly as... [Pg.19]

Figure 1 Generic polyketide assembly pathway reactions catalyzed by iterative fungal polyketide synthases. The assembly sequence for the squalesatin tetraketide intermediate 37 is shown for illustration. Figure 1 Generic polyketide assembly pathway reactions catalyzed by iterative fungal polyketide synthases. The assembly sequence for the squalesatin tetraketide intermediate 37 is shown for illustration.
Figure 1.7. Iterative deconvolution procedure illustrated by a combinatorial library consisting of a generic scaffold containing four variable building blocks A, B, C and D and in total 256 compounds. Figure 1.7. Iterative deconvolution procedure illustrated by a combinatorial library consisting of a generic scaffold containing four variable building blocks A, B, C and D and in total 256 compounds.

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