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51.
52.
Dr. Karl-Heinz Hoffmann 《Numerische Mathematik》1970,14(4):383-393
Summary In this paper we give some applications resulting from the theory of nonlinear approximation under side-conditions developed in a preceding paper [3]. Particularly a necessary condition for best approximation in terms of a generalized alternant is discussed, the approximating functions having restricted ranges. As special cases of this kind we deduce theorems for one-sided approximation and for approximations by positive functions. We conclude with a result in the theory of nonlinear programming.
Zweiter Teil einer gekürzten Fassung der Dissertation des Verfassers [3]. 相似文献
Zweiter Teil einer gekürzten Fassung der Dissertation des Verfassers [3]. 相似文献
53.
54.
55.
W. Stadler 《Journal of Optimization Theory and Applications》1979,29(1):1-52
In this survey, the history of the subject from 1776 until 1960 is presented. A brief biographical sketch of Vilfredo Pareto is given first. Then, the more or less simultaneous development of the concepts of utility, preference, and welfare theory follows, with results which go back to Hausdorff and Cantor. A brief discussion of the work of Borel and von Neumann as initiators of game theory is included. Each of these areas has developed enough to warrant its own survey; hence, they are reviewed here only insofar as they provide necessary foundations. Thereafter, the concepts of efficiency, vector maximum problem, and Pareto optimality are reviewed in connection with production theory, programming, and economics. The survey is presented within a unified mathematical framework, and the emphasis is on mathematical results, rather than psychological or socio-economic discussion. To enable the reader to draw conclusions without having to obtain each article himself, the results have been presented in somewhat more detail than usual. 相似文献
56.
W. Stadler 《Journal of Optimization Theory and Applications》1983,41(2):299-316
Necessary and sufficient conditions for the minimum mass design of arbitrarily loaded uniform shallow arches are derived. The problem is posed as an optimal control problem with mass as the criterion, initial curvature and axial load as design variables, and with the differential equations of axial and transverse equilibrium of the arch as side conditions. Thus, an optimal equilibrium is associated with each optimal design, and the stability of these equilibria becomes an integral part of the problem solution. As an example, the design process is carried out for the sinusoidally loaded hinged-hinged arch with a fixed span. It turns out that, depending on the given load amplitude, the optimal equilibrium can be unstable, stable after snap-through, and nonunique with one equilibrium unstable and the other stable after snap-through, at the design load of the arch. In addition, a necessary condition for a local minimum is the same as the usual critical point condition in stability analysis, thus assuring the instability of the arch at the optimum. A brief survey of earlier work on the optimal design of arches and curved beams is also included. 相似文献
57.
Karl-Heinz Thunemann Sigrid D. Peyerimhoff Robert J. Buenker 《Journal of Molecular Spectroscopy》1978,70(3):432-448
Large-scale configuration interaction calculations (including energy extrapolation) are reported for the various states of ozone and its positive ion. The first four dipole-forbidden electronic transitions in the O3 spectrum are calculated to occur at 1.20, 1.44, 1.59, and 1.72 eV, respectively, while the corresponding low-energy-allowed species known as the Chappuis, Huggins, and Hartley bands are predicted to possess vertical excitation energies of 1.95, 3.60, and 4.97 eV, respectively. These results all appear to fit in quite well with the observed location of the pertinent spectral features, with respect to both energy and intensity. The 5- to 8-eV region of the ozone spectrum is found to be characterized by a series of double-excitation transitions out of the highest three occupied orbitals to the lowest unoccupied 2b1(π*) species. The strong features observed at 9.3 and 10.2 eV are thereupon calculated to result primarily from transitions into the 7a1 (σ*) MO (calculated 9.29 and 10.05 eV) and in the former case also from the 3s members of the various O3 Rydberg series (calculated 9.21 and 9.38 eV). Finally the order of the first three ip's is found to be 6a1, 4b2, and 1a2, while the feature in the neighborhood of 16 eV is attributed to a shake-up state of 2B1 symmetry. 相似文献
58.
59.
W Stadler 《Journal of Mathematical Analysis and Applications》1973,42(2):409-412
60.
Karl-Heinz Helwig 《Mathematische Zeitschrift》1966,91(2):152-168
Ohne ZusammenfassungGefördert durch National Science Foundation grant GP-3750. 相似文献