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171.
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173.
Summary Motivated by different mean value properties, the functional equationsf(x) – f(y)/x–y=[(x, y)], (i)xf(y) – yf(x)/x–y=[(x, y)] (ii) (x y) are completely solved when, are arithmetic, geometric or harmonic means andx, y elements of proper real intervals. In view of a duality between (i) and (ii), three of the results are consequences of other three.The equation (ii) is also solved when is a (strictly monotonic) quasiarithmetic mean while the real interval contains 0 and when is the arithmetic mean while the domain is a field of characteristic different from 2 and 3. (A result similar to the latter has been proved previously for (i).) 相似文献
174.
175.
I. Palásti 《Periodica Mathematica Hungarica》1989,20(3):231-235
Here we establish a set of eight points in general position in the plane, i.e. no three on a line, no four on a circle, and they determine 7 distinct distances, so that, thei-th distance occursi times,i = 1, 2, , 7. The points are embedded in a triangular net, and the distances are not ordered by size or in any other way. We shall show that some known and unknown examples forn < 8 with the above properties may also be lattice points of a similar net.Research (partially) supported by the Hungarian National Foundation for Scientific Research (OTKA) grant, no. 1808. 相似文献
176.
In this paper the distribution of the zeros of the error function for bestL
1-approximation by rational functions fromR
n,m
is considered. It is shown that the maximal distance between such zeros isO(1/(n–m)), ifn > m.Communicated by Edward B. Saff. 相似文献
177.
The paper deals with the computer simulation of composite theoretical electron-diffraction patterns for metastable austenitic steels, containing deformation and martensite transformation structures. In many cases generated data can be used for interpretation of experimentally determined diffraction patterns. A few examples are presented which demonstrate that the application of the composite theoretical diffraction patterns may be complicated due to various diffraction effects which can modify the geometry of experimentally obtained diffraction patterns. 相似文献
178.
Linear mode conversion of waves near the maxima or minima of the density in a warm magnetized plasma
Behaviour of the h. f. electrostatic waves near the plasma or upper hybrid resonances was studied in the case that these resonances are situated at the maxima or minima of the plasma density. Supposing the parabolic density profile in these regions we obtained the connection formulae for the WKB solutions. In a weakly inhomogeneous magnetoplasma the effect of the parabolic profile manifests itself only in narrow frequency band centred at the resonance frequency corresponding to the extreme value of the density. The whole process can be then described by only two coefficients, viz. the power conversion and power transmission coefficients. 相似文献
179.
VI. Sedláček 《Czechoslovak Journal of Physics》1988,38(5):465-469
The formation of slip bands is the main mechanism of cyclic deformation in pure Al. Their density, orientation and heights in polycrystalline Al were investigated during cycling. Types, sizes and densities of precipitates are responsible for the mode of cyclic deformation in AlCu4 pure alloy. In technical Al alloys intermetallic phases have detrimental effects on deformation homogeneity and largely govern the fatigue mechanism of the material and especially microcrack initiation. 相似文献
180.
D. Macko V. Hajko Jr. J. Billy P. Makroczy V. Kavečanský O. Hudák 《Czechoslovak Journal of Physics》1988,38(12):1383-1386
Quasicrystalline Al-14 at. % Mn alloy was prepared by melt-spinning and its structural and electrical properties were studied. This alloy consists of icosahedral grains with sizes from 1 to 4 m and of crystalline aluminium phase. The electrical resistivity was almost temperature independent with a value of about 765 n gWm at 4·2 K. 相似文献