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1.
Summary A governmental Swedish committee has suggested conversion to ADP for the file maintenance involved in population registration, tax accounting etc. with a tape-oriented IBM 7070 and five IBM 1401 satellite computers. Investment in hardware, building etc. >6 M$; planning, programming, and file conversion 4 M$. Estimated annual savings, taking depreciation of initial costs into account: 2 M$/yr. Reduction of clerical force more than 1,000.  相似文献   

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Let KM be a finite field extension. An intermediate field L is called invariant if there is an affine algebraic K-group acting on M with L as its invariant field. The question, which intermediate fields are invariant, was studied by Bégueri [1] for purely inseparable extensions and by Sweedler [6] for arbitrary extensions, but only for a restricted class of groups. In this paper Bégueri's result is generalized to arbitrary field extensions. Additionally it is shown that one can check whether a given intermediate field is invariant or not by computing the rank of certain matrices. As an application we get a class of invariant intermediate fields.  相似文献   

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Zusammenfassung Möbiusgeometrien (K, L) über nicht notwendig kommutativen KörpernKL – eine Definition dieser Geometrien findet man in [1] — sind Verallgemeinerungen der Geometrie der Kreise auf der Riemannschen Zahlenkugel (K=,L=). In der vorliegenden Note wollen wir, unter Verzicht auf die Assoziativität vonL, Möbiusgeometrien auch für den Fall betrachten, woK ein im Zentrum des AlternativkörpersL enthaltener Körper ist, und (in Abschnitt 2) die Gruppe der Kreisverwandtschaften von (K, L) angeben. Dabei benutzen wir, anders als in [1] und [5], nur den Doppelverhältniskalkül, den wir gleichwertig zu der von A. Schleiermacher in [6] vorgeschlagenen Verallgemeinerung für kollineare Punkte einer Moufarigebene definieren. Es ergibt sich damit ein neuer Beweis des Satzes über Kettenverwandtschaften von (K, L) auch im assoziativen Fall. Die Verwendung von Doppelverhältnissen beim Beweis — auch bei charL=2-wird insbesondere durch das in Abschnitt 2 bewiesene Lemma (2.4) (Verallgemeinerung des sog. von Staudtschen Theorems; vgl. [2], [3]) ermöglicht.  相似文献   

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《Bl?tter der DGVFM》1963,6(2):253-263
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Summary A method is developed which allows to describe analytically the two-dimensional elastic wave-field in porous media disturbed by heterogeneities. In the first place circular inclusions are regarded, later inclusions of arbitrary contour.  相似文献   

7.
LetΛ={x=(x 1,...,x d )|x i ∈?} be a lattice in euclideand-spaceR d with respect to a rectangular coordinate system with unit vectors. Then for instance the following theorem holds: The number of lattice pointsG(K)=card (K∩Λ) of an arbitrary convex bodyK?R d is less or equal the volumeV(K λd) of the outer parallel bodyK λd ofK at a distance λ d d -1/d d =Volume of thed-unitsphere, 2≤d≤5). The number λ is best possible.  相似文献   

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Ohne ZusammenfassungHerrn Professor Dr.Reinhold Baer zum 60. Geburtstag am 22. 7. 1962 gewidmet  相似文献   

10.
Periodica Mathematica Hungarica - In the present note, we focus on the freeness and some combinatorial properties of line arrangements in the projective plane having only double and triple points....  相似文献   

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Ohne Zusammenfassung  相似文献   

13.
Sequent calculus for the provability logic GL is considered, in which provability is based on the notion of a circular proof. Unlike ordinary derivations, circular proofs are represented by graphs allowed to contain cycles, rather than by finite trees. Using this notion, we obtain a syntactic proof of the Lyndon interpolation property for GL.  相似文献   

14.
Ohne ZusammenfassungAuf Grund des Nachlasses vonF. Rellich bearbeitet vonErhard Heinz in Stanford/California  相似文献   

15.
In this paper, refinements of Holder's inequality are obtained and some concave functions are defined.  相似文献   

16.
Ohne ZusammenfassungDie vorliegende Arbeit verdankt ihre Entstehung und Förderung meinem verehrten Lehrer, Herrn Prof. Dr.E. Hlawka.  相似文献   

17.
An umbilic-free hypersurface in the unit sphere is called MSbius isoparametric if it satisfies two conditions, namely, it has vanishing MSbius form and has constant MSbius principal curvatures. In this paper, under the condition of having constant MSbius principal curvatures, we show that the hypersurface is of vanishing MSbius form if and only if its MSbius form is parallel with respect to the Levi-Civita connection of its MSbius metric. Moreover, typical examples are constructed to show that the condition of having constant MSbius principal curvatures and that of having vanishing MSbius form are independent of each other.  相似文献   

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φ: R→R. Nörlund [4] defined the principal solution fN of the difference equation $$V (x, y) \varepsilon R \times R_ + : \frac{1}{y}\left[ {g(x + y, y) - g(x, y)} \right] = \phi (x)$$ by V (x, y) ? [b, ∞) ×R+: $$f_N (x, y) : = \mathop {\lim }\limits_{s \to 0 + } ( \int\limits_a^\infty {\phi (t) e^{ - st} dt} - y \sum\limits_{\nu = 0}^\infty { \phi (x + \nu y) e^{ - s(x + \nu y )} } )$$ with suitable a,bεR and proved the existence of fN under certain restrictions onφ. In this paper, another way of defining a principal solution of the difference equation above, which includes Nörlund's, is gone. As an application, we construct in an easy manner a class of limitation methods for getting a principal solution, generalizing results from Nörlund [5].1)  相似文献   

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