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951.
An upper estimate for the topological entropy of a dynamical system defined by a system of ODE is obtained. The estimate involves
the Lyapunov functions and Losinskii’s logarithmic norm. The proof uses the known fact that the topological entropy of a mapping
acting in a compact space K can be estimated via the fractal dimension of K. Bibliography: 28 titles.
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 231, 1995, pp. 62–75.
Translated by V. A. Boichenko and G. A. Leonov. 相似文献
952.
Novosibirsk. Translated fromSibirskiî Matematicheskiî Zhurnal, Vol. 34, No. 3, pp. 3–18, May–June, 1993. 相似文献
953.
954.
955.
A. I. Skopin 《Journal of Mathematical Sciences》1993,63(6):684-692
A definition of the basis of a group written in additive form is given based on P. Hall's collecting process. The bases of free rank 2 groups of the following three types are found: metabelian, transmetabelian of the first type (with an Abelian third term in the lower central series), and transmetabelian of the second type (the nilpotency class of whose derived group is equal to two).Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova Akademiya Nauk SSSR, Vol. 191, pp. 126–139, 1991. 相似文献
956.
Orbital magnetism in an integrable model of a multichannel ring with long-ranged electron-electron interactions is investigated. In a noninteracting multichannel system, the response to an external magnetic flux is the sum of many diamagnetic and paramagnetic contributions, but we find that for sufficiently strong correlations, the contributions of all channels add constructively, leading to a parity (diamagnetic or paramagnetic) which depends only on the total number of electrons. Numerical results confirm that this parity-locking effect is robust with respect to subband mixing due to disorder. 相似文献
957.
Experimental study of the stability of stiffened shells (review) 总被引:1,自引:0,他引:1
958.
Richard A. Cairncross Jeffrey G. Becker Shri Ramaswamy Ryan O'Connor 《Applied biochemistry and biotechnology》1996,131(1-3):774-785
Management of moisture penetration and hydrolytic degradation of polylactide (PLA) is extremely important during the manufacturing,
shipping, storage, and end-use of PLA products. Moisture transport, crystallization, and degradation, in PLA have been measured
through a variety of experimental techniques including size-exclusion chromatography, differential scanning calorimetry, and
X-ray diffraction. Quartz crystal microbalance and dynamic vapor sorption experiments have also been used to measure moisture
sorption isotherms in PLA films with varying crystallinity. A surprising result is that, within the accuracy of the experiments,
crystalline and amorphous PLA films exhibit identical sorption isotherms. 相似文献
959.
We describe shaper cavities for the production of ultrashort microwave pulses with a minimum duration of one period of the high-frequency field and a power of several tens of megawatts. Experimental results are presented.Scientific and Research Insititute for Nuclear Physics at S. M. Kirov Polytechnical Institute, Tomsk. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 38, No. 12, pp. 1250–1256, December, 1995. 相似文献
960.