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961.
962.
A review of the advance in the theory of wavelet analysis in recent years is given. 相似文献
963.
Huang JM Yang CS Zhao R Takahashi H Fukuyama Y 《Chemical & pharmaceutical bulletin》2004,52(1):104-107
Seven new seco-prezizaane-type sesquiterpenes were isolated from the methanol extract of the pericarps of Illicium merrillianum. Their structures were elucidated as 3-deoxypseudoanisatin (1), 2beta-hydroxy-3,6-dedioxypseudoanisatin (2), 8alpha-hydroxy-10-deoxycyclomerrillianolide (3), 10beta-hydroxypseudoanisatin (4), 10beta-hydroxycyclopseudoanisatin (5), 1,6-dihydroxy-3-deoxyminwanensin (6), and 8-deoxymerrilliortholactone (7) by analyses of their spectroscopic data and chemical transformation. Compounds 4 and 5 as well as 6 and 7 coexist as a keto/acetal equilibrated mixture in methanol solution. 相似文献
964.
965.
966.
Tiehui Liu Zhijiang Chen Tao Huang 《Zeitschrift fur Physik C Particles and Fields》1990,46(1):133-140
The various properties of quarkonium systems have been studies in the framework of a recently proposed potential model, which combines the asymptotic freedom at the largeQ 2 and the multigluon effect at the lowerQ 2 regions with the confinement at the large distance. Good agreements with experiments are found, including \(c\bar c\) and \(b\bar b\) energy levels, leptonic decay widths, and in particular the fine and hyperfine splittings. We also analyze the Lorentz structure of the confinement potential with reference to the charmonium and bottomium fine and hyperfine splittings. Our analyses conclude that almost pure scalar confinement is favored. The properties of \(t\bar t\) spectroscopies are studied over a wide range of \(M_{t\bar t}\) values (from 80 GeV to 200 GeV). 相似文献
967.
968.
Brick DH Widgoff M Beilliere P Lutz P Narjoux JL Gelfand N Alyea ED Bloomer M Bober J Busza W Cole B Frank TA Fuess TA Grodzins L Hafen ES Haridas P Huang D Huang HZ Hulsizer R Kistiakowsky V Ledoux RJ Milstene C Noguchi S Oh SH Pless IA Steadman S Stoughton TB Suchorebrow V Tether S Trepagnier PC Wadsworth BF Wu Y Yamamoto RK Cohn HO Calligarich E Castoldi C Dolfini R Introzzi G Ratti S Badiak M DiMarco R Jacques PF Kalelkar M Plano RJ Stamer PE Brucker EB Koller EL Alexander G Grunhaus J 《Physical review D: Particles and fields》1990,41(3):765-773
969.
This paper is concerned with a combined production-transportation scheduling problem. The problem comprises a simple, two-machine, automated manufacturing cell, which either stands alone or is a subunit of a complete flexible manufacturing system. The cell consists of two machines in series with a dedicated part-handling device such as a crane or robotic arm for transferring parts from the first machine to the second. The loading of a new piece on the first machine and the ejection of a finished piece from the second machine are performed by dedicated automated mechanisms. The introduction of parts into the system is done n at a time, whereby the parts are reshuffled into a sequence that minimizes completion time. All processing and transfer times are considered deterministic—a reasonable assumption for a cell comprising a robotic transfer device and two CNC machining units. What complicates the problem is the assumption of a non-negligible time for the transfer device to return (empty) from the second machine to the first. The operation is a generalization of a two-machine flowshop problem, and is formulated as a specially structured, asymmetric travelling salesman problem. An approximate polynomial time 0(n log n) algorithm is proffered. The procedure incorporates a lower bound using the Gilmore–Gomory algorithm for the no-wait, two-machine flowshop problem. 相似文献
970.