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81.
ZHAO Wei-Qin 《理论物理通讯》2004,42(7)
A revised iterative method based on Green function defined by quadratures along a single trajectory is proposed to solve the low-lying quantum wave function for Schrodinger equation. Specially a new expression of the perturbed energy is obtained, which is much simpler than the traditional one. The method is applied to solve the unharmonic oscillator potential. The revised iteration procedure gives exactly the same result as those based on the single trajectory quadrature method. A comparison of the revised iteration method to the old one is made using the example of Stark effect. The obtained results are consistent to each other after making power expansion. 相似文献
82.
We consider quasistable multicriteria problems of discrete optimization on systems of subsets (trajectory problems). We single
out the class of problems for which new Pareto optima can appear, while other optima for the problems do not disappear when
the coefficients of the objective functions are slightly perturbed (in the Chebyshev metric). For the case of linear criteria
(MINSUM), we obtain a formula for calculating the quasistability radius of the problem.
Translated fromMatemalicheskie Zametki, Vol. 63, No. 1, pp. 21–27, January, 1998.
This research was supported by the Belarus Foundation for Basic Research under grant No. F95-70. 相似文献
83.
Fissile radionuclides in thyroid of the inhabitants of the gomel region in belarus and peculiarities of their distribution 总被引:1,自引:0,他引:1
A. F. Malenchenko N. V. Kanash N. N. Bazhanova I. V. Zhuk E. M. Lomonosova M. K. Kievetz S. F. Boulyga 《Radiation measurements》1997,28(1-6):397-400
Severe radiation damages with the following substitution of connective tissue are the effect of high doses in microvolumes of the thyroid. Calcium, strontium and uranium deposited into these sections was more as compared to a normal tissue of the thyroid. An estimation of the microdistribution of fissile radionuclides was carried out using the method of fragmental radiography. The analysis of tracks done visually using a microscope magnification of 300 revealed the local density of fission fragments up to 103 mm−2. The irradiation of the surrounded cells which contain the hidden genetic damages, initiated by radioiodine, does not exclude their possible promoter role in thyroid cancerogenesis. 相似文献
84.
85.
Track method (using the CN and CR-39 detectors, spark couner of tracks as well as selective sorbents for plutonium and uranium) is applied in 1994 and 1995 together with many other methods in radioecological monitoring of water in the region of the sunken nuclear submarine (NS) “Komsomolets”. The detection assembles were installed with the help of the submersibles MIR. The results obtained inside the NS and on its surface as well as near and on the remote buoy station do not contradict the data obtained by other methods confirming the absence of the plutonium leakage outside of the submarine. 相似文献
86.
在气轨上有关变质量规律的实验研究 总被引:1,自引:0,他引:1
本文介绍一种新型的变质量实验装置,借助气垫导轨可验证变质量下的动量定理和运动方程等规律。 相似文献
87.
R. W. Kieboom 《Applied Categorical Structures》1997,5(2):131-142
It is well known that the concept of monomorphism in a category can be defined using an appropriate pullback diagram. In the homotopy category of TOP pullbacks do not generally exist. This motivated Michael Mather to introduce another notion of homotopy pullback which does exist. The aim of this paper is to investigate the modified notion of homotopy monomorphism obtained by applying the pullback characterization using Mather's homotopy pullback. The main result of Section 1 shows that these modified homotopy monomorphisms are exactly those homotopy monomorphisms (in the usual sense) which are homotopy pullback stable, hence the terminology “stable” homotopy monomorphism. We also link these stable homotopy monomorphisms to monomorphisms and products in the track homotopy category over a fixed space. In Section 2 we answer the question: when is a (weak) fibration also a stable homotopy monomorphism? In the final section it is shown that the class of (weak) fibrations with this additional property coincides with the class of “double” (weak) fibrations. The double (weak) covering homotopy property being introduced here is a stronger version of the (W) CHP in which the final maps of the homotopies involved play the same role as the initial maps. 相似文献
88.
等变集压缩场的零点指标公式 总被引:4,自引:0,他引:4
本文在紧致李群作用下的Banach空间中,讨论了等变严格集压缩场的正则零点轨道的指标计算问题,推广了(1),(2)的结果。 相似文献
89.
90.
The molecular structure of SR-90 and CR-39 is very similar except that the average length of carbonate linkages in SR-90 is 1.6 times longer than in CR-39. However, the effect of vacuum and carbon dioxide (CO2) on the track registration of these two detectors is very different: 1) the sensitivity of CR-39 becomes very low in vacuum; the sensitivity of SR-90 does not go down to zero even after storage in vacuum for a long time; 2) the sensitivity of SR-90 decreases both in air and in vacuum but the original sensitivity can be restored by storing it in CO2 of 13 atm for several days. We also found that the sensitization of latent tracks by oxygen (O2) is effective only at the time of irradiation but the sensitization by CO2 is effective after irradiation. 相似文献