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Reduced gradient following

The following strategies are all examples of Generahzed Reduced Gradient (GR< methods. [Pg.485]

To solve this first reduced problem, follow the steps of the descent algorithm outlined at the start of this section with some straightforward modifications that account for the bounds on x and y. When a nonbasic variable is at a bound, we must decide whether it should be allowed to leave the bound or be forced to remain at that bound for the next iteration. Those nonbasic variables that will not be kept at their bounds are called superbasic variables [this term was coined by Murtaugh and Saunders (1982)]. In step 1 the reduced gradient off(x,y) is... [Pg.310]

The initial search direction is, as usual, the negative reduced gradient direction so d = [0 2] and we move from (0.75,0) straight up toward the line x + y = 1. The output from GRG is shown in the following box. [Pg.317]

Solve the following problems by the generalized reduced-gradient method. Also, count the number of function evaluations, gradient evaluations, constraint evaluations, and evaluations of the gradient of the constraints. [Pg.336]

The generalized reduced gradient (GRG) transforms inequality constraints into equality constraints by introducing slack variables [24]. Hence all the constraints in (P) are of equality form and can be represented as follows ... [Pg.433]

The foregoing analysis indicates that it is important to get a closer picture of the behavior of the density and its gradient in different regions of a molecule. To do this, one can follow the procedure of Johnson et al.," " in which the reduced gradient... [Pg.304]

Topaz was used to calculate the time response of the model to step changes in the heater output values. One of the advantages of mathematical simulation over experimentation is the ease of starting the experiment from an initial steady state. The parameter estimation routines to follow require a value for the initial state of the system, and it is often difficult to hold the extruder conditions constant long enough to approach steady state and be assured that the temperature gradients within the barrel are known. The values from the Topaz simulation, were used as data for fitting a reduced order model of the dynamic system. [Pg.496]

Osmotherapy employs agents such as mannitol, glycerol, and hypertonic saline to create an osmotic gradient between the brain (optimally, the edematous infarcted tissue) and the bloodstream, such that water is drawn out from the brain, thereby reducing edema. Each of these agents has been shown to be effective, and may be used alone or in combination with a diuretic, such as furosemide. Their action, however, depends upon an intact blood-brain barrier (BBB), and concerns have been raised for possible paradoxical worsening when one is absent. In this hypothesis, mannitol extravasates from the vessel into the interstitial tissue and water follows a new osmotic... [Pg.173]

As described above, because MAO is bound to mitochondrial outer membranes, MAOIs first increase the concentration of monoamines in the neuronal cytosol, followed by a secondary increase in the vesicle-bound transmitter. The enlarged vesicular pool will increase exocytotic release of transmitter, while an increase in cytoplasmic monoamines will both reduce carrier-mediated removal of transmitter from the synapse (because the favourable concentration gradient is reduced) and could even lead to net export of transmitter by the membrane transporter. That MAOIs increase the concentration of extracellular monoamines has been confirmed using intracranial microdialysis (Ferrer and Artigas 1994). [Pg.433]


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See also in sourсe #XX -- [ Pg.221 ]




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Reduced gradient

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