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981.
The characteristics of the distribution of magnetization and remagnetization of microsections of the surface in the amorphous alloy Co70Fe5Si10B15, prepared in the form of thin ribbons, were studied by the magnetooptical method. It was found that the magnetization I on the surface of the amorphous ribbon studied was strongly nonuniform. It was established that heat treatment (HT) of the sample leads to the appearance of regions of reversed magnetization in the surface layer of the ribbon, while thermomagnetic annealing reduces the nonuniformity of I. The conservation of the transverse component in the HT sample in fields where the magnitude of the component of magnetization parallel to the length of the ribbon remains virtually unchanged suggested that a domain structure of the magnetization ripple type, owing to the strong microdispersion of the magnetic anisotropy, is realized in this sample.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 89–94, March, 1988.  相似文献   
982.
By the automorphic approach and the use of computer graphics, we carry out a qualitative analysis of finite-gap periodic solutions of the Kg equation. Graphs are constructed for multiphase solutions.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 165, pp. 31–41, 1987.  相似文献   
983.
An existence theorem is proved for closed convex surfaces whose principal radii of curvature regarded as functions of the unit normal vectorn satisfy the equation
  相似文献   
984.
It is proved that the solution of the general existence problem for closed convex surfaces with prescribed local propertiesf(R 1 R 2,R 1+R 2,n)=(n) can be obtained as the solution of Miranda's equationR 1 R 2+(f)+cn=((n),(n)) with right-hand side depending on the unknown surface under the hypothesis that the latter satisfies the closure condition , where is the unit sphere andd is its element of area.Translated from Ukrainskií Geometricheskií Sbornik, Issue 29, 1986, pp. 103–112.  相似文献   
985.
Majorants of the fractal dimension and of the number of determining modes for unbounded sets, invariant with respect to operators of semigroups of classes 1 and 2, are obtained. They are computed for the Navier-Stokes equations (two- and three-dimensional) under the first boundary condition and under periodicity conditions in the spaces and .Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 163, pp. 105–129, 1987.  相似文献   
986.
In this article we prove that the principal direction fields are holonomic and use them to introduce curvilinear coordinates on an immersed region in terms of which the linear element of Lobachevskií space is written in the form where The fundamental system of equations is established for an immersion ofn-dimensional Lobachevskií space into 2n-dimensional Euclidean space withn principal direction fields for the functions i and, and a way of constructing an arbitrary local analytic immersion is shown.Translated from Ukrainskií Geometricheskií Sbornik, No. 28, pp. 3–8, 1985.  相似文献   
987.
A theorem is proved regarding the expansion in the eigenfunctions of the one-dimensional Schrödinger equationL = –d z/dx 2+q(x)(–<x<)with a potential q(x), satisfying the condition
  相似文献   
988.
To the sh-Gordon equation
  相似文献   
989.
Spread sets of projective planes of order q 3 are represented as sets of q 3 points in A AG(3, q 3). A line through the origin in A can be interpreted as a space A 0 AG(3, q), and the spread set induces a cubic surface L in A 0. If the projective plane is a semifield plane of dimension 3 over its kernel, then L has the property that it misses a plane of A 0. Determining all such surfaces L leads to a complete classification of the semifield planes of order q 3, whose spread sets are division algebras of dimension 3.An alternative proof of a result due to Menichetti, that finite division algebras of dimension 3 are associative or are twisted fields, follows with the classification.  相似文献   
990.
Wave processes in dissipative-dispersive media with instability described by a fourth-order nonlinear evolution equation are considered. Analytic solutions in the form of solitary and cnoidal waves are obtained. The existence of a critical value of the dispersion coefficient beyond which an initial disturbance (in particular, white noise) is transformed into a structure is demonstrated by numerical modeling.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 4, pp. 130–136, July–August, 1990.  相似文献   
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