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91.
92.
Models are developed for decision making about monitoring andmaintenance of systems whose performance through time is describedby a general stochastic process. The system is monitored andpreventive and corrective maintenance actions are carried outin response to the observed system state. The decision processis simplified by using the maximum process as a decision variable.The models developed generalize age replacement models and othersimple maintenance strategies. The approach can deal with failuresthat prevent the system functioning further, and also failuresthat are defined by regulation or economic considerations. Attentionis restricted to perfect repair and inspection, but the structureprovides the framework for further developments. 相似文献
93.
Martin Breza 《Czechoslovak Journal of Physics》1992,42(2):201-207
The electronic structure of YBa2Cu3Ox (x=6 and 7) is investigated using the CNDO molecular orbital method. Electronic structures of model clusters [Cu3O10]–15, [Ba8Cu3O10]+1, [Y8Cu3O10]+9 of the non-superconducting (x=6) and [Cu3O12]–17, [Ba8Cu3O12]–1, [Y8Cu3O12]+7 of the superconducting (x=7) phases are compared. Y and Ba layers cause a considerable electron density transfer from the central Cu(1) region. 相似文献
94.
95.
Tomomi Kawasaki Miyuki Nagaoka Tomoko Satoh Ayako Okamoto Rie Ukon Atsuyo Ogawa 《Tetrahedron》2004,60(15):3493-3503
Claisen rearrangement triggered by enolization of 2-allyloxyindolin-3-ones with DBU was performed in order to prepare 3-allyl-3-hydroxyindolin-2-ones. Total synthesis of 3-hydroxyindolin-2-one alkaloids, (±)-donaxaridine, as well as (±)-convolutamydines A and E, was achieved by transformation of the allyl moiety of 3-allyl-3-hydroxyindolin-2-ones. 相似文献
96.
Martin E. V. Pedersen Lars S. Rishøj Henrik Steffensen Sanshui Xiao Niels Asger Mortensen 《Optical and Quantum Electronics》2007,39(10-11):903-911
Slow-light enhanced optical detection in liquid-infiltrated photonic crystals is theoretically studied. Using a scattering-matrix approach and the Wigner–Smith delay time concept, we show that optical absorbance benefits both from slow-light phenomena as well as a high filling factor of the energy residing in the liquid. Utilizing strongly dispersive photonic crystal structures, we numerically demonstrate how liquid-infiltrated photonic crystals facilitate enhanced light–matter interactions, by potentially up to an order of magnitude. The proposed concept provides strong opportunities for improving existing miniaturized absorbance cells for optical detection in lab-on-a-chip systems. 相似文献
97.
We study the metrical theory of fibred systems, in particular, in the case of continued fraction mixing systems. We get the
limit distribution of the largest value of a continued fraction mixing stationary stochastic process with infinite expectation
and some related results. These are analogous to J. Galambos, W. Philipp, and H. G. Diamond–J. D. Vaaler theorems for the
regular continued fractions. As an application, we see that these theorems hold for Jacobi-Perron algorithm.
Received September 30, 2001; in revised form January 8, 2002 相似文献
98.
Martin Traizet 《Commentarii Mathematici Helvetici》2004,79(4):798-825
We prove a balancing condition for weak limits of
families of embedded
minimal surfaces of finite total curvature. We use it to
prove compactness theorems for certain families of minimal
surfaces. 相似文献
99.
100.