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21.
H.-P. Butzmann 《Applied Categorical Structures》2001,9(4):365-368
In this paper we construct complete, regular convergence vector spaces E and F such that c(E,F), the space of all continuous linear mappings from E to F, endowed with the continuous convergence structure, is not complete. 相似文献
22.
Gustavo Garrigó s Darrin Speegle 《Proceedings of the American Mathematical Society》2000,128(4):1157-1166
We study the completeness properties of the set of wavelets in . It is well-known that this set is not closed in the unit ball of . However, if one considers the metric inherited as a subspace (in the Fourier transform side) of , we do obtain a complete metric space.
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Jan Kucera 《Czechoslovak Mathematical Journal》2001,51(1):181-183
Any LF-space is sequentially complete iff it is regular. 相似文献
26.
Instantaneous phase shifting arrangement for microsurface profiling of flat surfaces 总被引:1,自引:0,他引:1
Phase shifting interferometry is a well-established technique for non-contact surface profile measurement. Though phase shifting technique has many advantages, it is marred by a few inaccuracies due to the vibration and mechanical movement of the phase shifter itself. Significant amount of work is reported to theoretically compensate these error sources. But for a few works, prominent achievements have not been reported in eliminating these error sources in phase shifting interferometry. In this paper, a novel optical layout, in combination with instantaneous phase shifting interferometry is described. Experiments were carried out with this setup on a super mirror with a λ/20 surface roughness, to demonstrate the validity of the principle. 相似文献
27.
给出了罗尔微分中值定理的三种新的证明方法,其中第二种很简便的方法仅依赖于大家熟知的Heine-Borel有限覆盖定理.由此可见罗尔微分中值定理可以是实数的完备性的直接推论. 相似文献
28.
Instantaneous frequency measurement based on complementary microwave photonic filters with a shared Mach-Zehnder interferometer 总被引:1,自引:0,他引:1
A novel configuration using only one Mach-Zehnder interferometer (MZI) for photonic-assisted instantaneous microwave frequency measurement is proposed. The amplitude comparison function (ACF), related to the input microwave frequency while independent of the input optical power and modulate index, is achieved by using a ratio of low-pass to bandpass frequency responses introduced by intensity and phase modulation with a shared MZI. The microwave frequency can be estimated by the measured ACF. A proof-of-concept experiment for measurement of RF from 5 to 10 GHz is successfully demonstrated with the measurement errors less than ± 0.2 GHz. 相似文献
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