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Extreme problems

This condition constitutes the Euler-Lagrange (EL) equation of the extremal problem, with the proportionality constant A being the Lagrange multiplier. Its concrete... [Pg.181]

Some conjectural solutions of many extremal problem on the sphere (Thomson, Tammes, Skyrme problems, etc.) have (solving exactly the problem is almost impossible) the combinatorial structure of GCkfiDodecahedron) or its dual (see [HaS196]). [Pg.28]

Optimization of a research subject is the hardest research problem. It should immediately be noted that different optimization problems appear in practice. In most cases extreme problems are present, problems of searching for extremes (minima and maxima) of a response function in the case of one response and with factor limitations. Most such problems have to do with finding the maxima of outlet and minima of inlet parameters. There are situations too where response improvement with regard to initial state in null point is required. Often, there is a demand for finding the local optimum if there are more of these. [Pg.169]

Determination of optimal conditions in the lab, pilot and full-scale plants is among the most complex problems for a researcher and it belongs to the group of extreme problems. This complexity is caused by the nature of technological processes, which simultaneously include chemical reaction, transfer of mass, heat transfer and momentum transfer. It does not allow to form, by well-known theoretical knowledge, a deterministic model for establishing an optimum analytically. [Pg.385]

This technique is of immense potential importance but so far has been of very limited applicability towards short-lived intermediates. It is too slow for use in flash photolysis and there are extreme problems of sensitivity in matrix-isolation experiments. Although the feat of obtaining H and C... [Pg.4377]

Besides the measure of the dispersion of the one-dimensional projection i.e. the projective index, another distinction of PP PCA from the classical PCA is the procedure of computation. Since the projective index is the quadratic form of X as stated above, the extremal problem of Eqn. 1 can be turned into the problem of finding the eigenvalues and eigenvectors of the sample covariance matrix for which a lot of algorithms such as SVD, QR are available. Because of the adoption of the robust projective index in PP PCA, some nonlinear optimization approaches should be used. In order to guarantee the global optimum. Simulated annealing (SA) is adopted which is the main topic of this book. [Pg.63]

J. Saeman It can be very high. Some tropical species run up to 10%. It is so prominent that it is an extreme problem in sawing. In some species you can strike sparks from a saw as a result of sawing through the silica in the wood. ... [Pg.286]

RAHMAN, Qazi Ibadur, Applications of Functional Analysis to Extremal Problems for Polynomials, (6e session, 6t6 1967), Les PresTes de I Univer-site de Montreal, 1968, 69 p., 2.00. [Pg.94]

Both my lower legs tended to fall asleep, and this seemed to spread to my hands and lower arms. It was uncomfortable and although I was apprehensive at first it didn t get any worse with time so I ignored it. This is not one my favorite materials, and it takes too long to wear off. If I were to do it again I would settle for 4 or 5 milligrams. It may well cut out the extremity problem amd still allow for a pleasant experience. [Pg.748]

So there is a sufficient number of equations to solve the extremal problem. If there is a constraint relation between xi, X2, , Xk, say Ckixi, X2, Xk) = 0, then we can resolve this relation, say into Xk, and substitute into Eq. (1.40) to get a set of equations like... [Pg.24]

Here x and y are the lengths of the edges of the rectangle. Problems of this type frequently appear in mathematical physics, in particular in the more advanced calculus of variation. We will address this set of somehow related problems as reciprocal extremal problems. [Pg.28]

The Feasibility Study accompanied by the above materials was submitted to the Federal Executive Authorities for expert evaluation, approval and licensing (expert opinion of the Federal Medical and Biological and Extreme Problems has been already obtained). [Pg.64]

The presence of polymers in some systems can cause difficult problems where foam stability is not desirable. Such is particularly the case in waste treatment facihties, where the presence of proteins can cause extreme problems. If polyvalent ions such as Ca and are present, the problem is exacerbated still more. Proteins will bond strongly with such ions and form an essentially cross-finked surface film so rigid that it may approach the strength of a solid foam. Obviously, such a situation will be detrimental to the overall treatment process. In other situations, such as breads and other baked products, the formation of rigid foam walls can be particularly advantageous. [Pg.306]

An heuristic combination of original features may also be used to generate new features however, such methods are extremely problem-depen-dent. Bender, Kowalski and Shepherd C16, 173 investigated several possibilities for the representation of mass spectra means, moments, number of peaks, histograms, etc. were successfully used as new features. [Pg.105]

Train and Tmax are interpreted as the maximum and minimum intervals between two successive forms. To solve such problems, the principle of maximum likelihood is used. It has been shown by the authors that noise-immune maximum likelihood detection of a given number of unknown wave forms can be simulated by the following discrete extremal problems ... [Pg.193]

Rural electrification, therefore, presented economic challenges based on the costs of service provision to a low-density, widely dispersed, often relatively poor population, and engineering issues (especially in relation to hydro schemes) to do with topography and environmental obstacles. Remoter island communities off the west coast epitomized the extreme problems for a rural electricity service for sparsely populated areas. [Pg.1888]


See other pages where Extreme problems is mentioned: [Pg.916]    [Pg.11]    [Pg.307]    [Pg.292]    [Pg.3]    [Pg.28]    [Pg.52]    [Pg.917]    [Pg.2]    [Pg.8]    [Pg.187]    [Pg.72]    [Pg.45]    [Pg.2]    [Pg.278]    [Pg.132]    [Pg.167]    [Pg.28]    [Pg.125]    [Pg.166]    [Pg.292]    [Pg.33]    [Pg.223]    [Pg.89]    [Pg.817]    [Pg.1000]    [Pg.194]    [Pg.27]    [Pg.124]   
See also in sourсe #XX -- [ Pg.169 , Pg.385 ]

See also in sourсe #XX -- [ Pg.169 , Pg.385 ]




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