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排序方式: 共有2796条查询结果,搜索用时 15 毫秒
111.
考虑有独立调整时间的同型号平行机排序问题,极小化最迟完工时间,产品允许拆分,同一产品被拆分后各部分可以在不同机器上同时加工,该问题是NP-hard问题。本文首先给出该问题的一个启发式算法ML,然后证明了其最坏情况估计不超过7/4-1/m(m≥2)。 相似文献
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Yu?A.?KarpovEmail author T.?A.?Makarova D.?F.?Makarov A.?P.?Kuznetsov 《Accreditation and quality assurance》2004,9(7):404-410
Problems verifying the accuracy of analyses of non-standardized materials for precious metal (PM) content have arisen at the Norilsky Nickel plant, which is a major producer of nickel, copper, and PMs in Russia. Because of the unavailability of certified reference samples for direct accuracy verification, a program of interlaboratory comparisons (ILC) was developed. This program was based on testing three semi-products of the PM production process for PM content. On program completion, a total of 826 results in 98 runs had been obtained. For each run, the calculated mean value of PM concentration was taken to be the reference value. The results obtained by Norilsky Nickel were in agreement with the reference values within the standard deviations calculated for the values. The quality of results yielded with the ILC program, as assessed via the Z-criterion, is regarded as satisfactory.Presented at the Second International Conference on Metrology – Trends and Applications in Calibration and Testing Laboratories, November 4–6, 2003, Eilat, Israel. 相似文献
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F. Michelot M. Rey 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(3):467-495
Effective vibronic Hamiltonian models are built for E ⊗e Jahn-Teller systems and analytical solutions are
obtained through Lie algebraic methods. Although approximate, we show that these models allow in particular to recover the
possible ground state crossover when quadratic couplings are present. The equivalence of E ⊗e and G' ⊗e
vibronic systems in cubic symmetry is precisely established through a particular realization of the electronic operators for
an
orbital quadruplet. We show how this equivalence is broken by a rovibronic interaction which, for a G' ⊗e system, still
gives an exactly solvable model. 相似文献
118.
Hiroshi Yamatani 《Surface science》2007,601(22):5284-5288
We have developed an ultrahigh-vacuum (UHV) complex sample preparation and analysis system, which realizes a reliable surface science analyzing various characters on an identical surface. The system contains three sample-preparation-and-characterization chambers and five analysis chambers. They are (1) an electronic-properties-characterization chamber, (2) a magnetic-properties-characterization chamber, (3) an organic-molecule chamber, (4) UHV SEM, (5) a high-energy-resolution angle-resolved photoelectron spectrometer, (6) a high-energy-resolution display-type spherical mirror analyzer, (7) a room-temperature (RT) STM, and (8) an optical-properties characterization chamber. A special sample holder is used with six electrodes on it, which enables accurate temperature measurement of a sample by connecting a thermocouple directly to the sample even if it is transferred. Four other electrodes can be used for construction of various circuits including evaporators. Some examples are shown. 相似文献
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如今移动搜索已经变成了一个时兴的话题.几年之间.它从无到有,既有广阔的前景.也在发展中面也面临着各种障碍。本文就移动搜索的现状进行了多方面的分析,并对于未来的发展策略进行了思考.给出一些个人的建议。 相似文献