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Optima local

Whole-body MRS is potentially the most powerful tool available for the study of human metabolism in vivo. The nuclide s low natural abundance (1.1%) allows the study of important biological molecules such as glycogen and lipids, while at the same time allowing the use of C-enriched compounds in dynamic measurements of intermediate metabolism. However, several technical issues need to be addressed before its implementation in vivo, including a second transmit channel, optimum localization and proton decoupling. The latter has been one of the major stumbling blocks for the application of in vivo... [Pg.857]

This section covers the interaction between the chosen materials of the substrate and their geometry, on the one hand, and optimum local surface conditions on the other. These surface conditions are developed to benefit both functional fulfillment and corrosion control, and close co-operation between design engineers, corrosion specialists, and technical experts in individual fields of surface-treatment technology is highly recommended. [Pg.337]

One of the most important theoretical results in optimization are the Karush, Kuhn and Tucker conditions. They must be satisfied at any optimum, local or global, of any linear and most nonlinear programs. The vector or e K satisfies these conditions for the program (A.l) if there exists vectors fi eW" and X e such that... [Pg.257]

In contrast to a direct injection of dc or ac currents in the sample to be tested, the induction of eddy currents by an external excitation coil generates a locally limited current distribution. Since no electrical connection to the sample is required, eddy current NDE is easier to use from a practical point of view, however, the choice of the optimum measurement parameters, like e.g. the excitation frequency, is more critical. Furthermore, the calculation of the current flow in the sample from the measured field distribution tends to be more difficult than in case of a direct current injection. A homogenous field distribution produced by e.g. direct current injection or a sheet inducer [1] allows one to estimate more easily the defect geometry. However, for the detection of technically relevant cracks, these methods do not seem to be easily applicable and sensitive enough, especially in the case of deep lying and small cracks. [Pg.255]

Mountain-climbing analogy to using a searching algorithm to find the optimum response for a response surface. The path on the left leads to the global optimum, and the path on the right leads to a local optimum. [Pg.668]

In order to obtain a homogenous and stable latex compound, it is necessary that insoluble additives be reduced in particle size to an optimum of ca 5 )Tm and dispersed or emulsified in water. Larger-size chemical particles form a nucleus for agglomeration of smaller particles and cause localized dispersion instabiHty particles <3 fim tend to cluster with similar effect, and over-milled zinc oxide dispersions are particularly prone to this. Water-soluble ingredients, including some accelerators, can be added directly to the latex but should be made at dilute strength and at similar pH value to that of the latex concentrate. [Pg.252]

Hard plating is noted for its excellent hardness, wear resistance, and low coefficient of friction. Decorative plating retains its brilliance because air exposure immediately forms a thin, invisible protective oxide film. The chromium is not appHed directiy to the surface of the base metal but rather over a nickel (see Nickel and nickel alloys) plate, which in turn is laid over a copper (qv) plate. Because the chromium plate is not free of cracks, pores, and similar imperfections, the intermediate nickel layer must provide the basic protection. Indeed, optimum performance is obtained when a controlled but high density (40—80 microcrack intersections per linear millimeter) of microcracks is achieved in the chromium lea ding to reduced local galvanic current density at the imperfections and increased cathode polarization. A duplex nickel layer containing small amounts of sulfur is generally used. In addition to... [Pg.119]

When an optimum is reached, the perturbation ia any direction would reduce the value of the objective function. Such an optimum, however, does not guarantee a global optimum, and the mountain-climbing process stops at a local optimum. [Pg.79]

At each step q may be calculated to give a locally optimum value by setting... [Pg.469]

Most strategies hmit themselves to finding a local minimum point in the vicinity of the starting point for the search. Such a strategy will find the global optimum only if the problem has a single minimum point or a set of connected minimum points. A convex problem has only a global optimum. [Pg.485]

A distribution network 33 kV, three-phase 50 Hz feeding an industrial belt with a number of medium-sized factories some with non-linear loads and some with static drives and some with both. It was observed that while the lines were apparently running reasonably loaded, the active power supplied was much below the capacity of the network. Accordingly, a harmonic study of the network was conducted and it was found that despite localized p.f. control by most factories, the p.f. of the network itself was well below the optimum level and the voltage was also distorted by more than was permissible. To improve this network to an acceptable level, we have considered the following load conditions, as were revealed through the analysis. [Pg.748]

A second calculation was done for a two-layer tubule using density functional theory in the local density approximation to establish the optimum interlayer distance between an inner (5,5) armchair tubule and an outer armchair (10,10) tubule. The result of this calculation yielded a 3.39 A interlayer separation... [Pg.32]

The optimum value of c is determined by the variational principle. If c = 1, the UHF wave function is identical to RHF. This will normally be the case near the equilibrium distance. As the bond is stretched, the UHF wave function allows each of the electrons to localize on a nucleus c goes towards 0. The point where the RHF and UHF descriptions start to differ is often referred to as the RHF/UHF instability point. This is an example of symmetry breaking, as discussed in Section 3.8.3. The UHF wave function correctly dissociates into two hydrogen atoms, however, the symmetry breaking of the MOs has two other, closely connected, consequences introduction of electron correlation and spin contamination. To illustrate these concepts, we need to look at the 4 o UHF determinant, and the six RHF determinants in eqs. (4.15) and (4.16) in more detail. We will again ignore all normalization constants. [Pg.112]

There apparently exists a critical amount of liquid phase for the optimization of grain/interface boundary sliding during superplastic deformation. The optimum amount of liquid phase may depend upon the precise material composition and the precise nature of a grain boundary or interface, such as local chemistry (which determines the chemical interactions between atoms in the liquid phase and atoms in its neighboring grains) and misorientation. The existence of an equilibrium thickness of intergranular liquid phase in ceramics has been discussed [14]. This area of detailed study in metal alloys has not been addressed. [Pg.422]


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See also in sourсe #XX -- [ Pg.11 ]

See also in sourсe #XX -- [ Pg.12 , Pg.37 , Pg.39 , Pg.40 , Pg.41 , Pg.42 , Pg.43 , Pg.46 , Pg.47 , Pg.51 , Pg.52 , Pg.53 ]

See also in sourсe #XX -- [ Pg.26 , Pg.37 ]




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Local optimum, definition

Local vs. global optima

Presence of Several Local Optima

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