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A stabilization problem for Burgers' equation is considered. Using linearization, various controllers are constructed which minimize certain weighted energy functionals. These controllers produce the desired degree of stability for the closed-loop nonlinear system. A numerical scheme for computing the feedback gain functional is developed and several numerical experiments are performed to illustrate the theoretical results. 相似文献
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The use of emission spatial profiles for the establishment of an internal reference point in ICP-AES
T.A. Anderson D.W. Burns M.L. Parsons 《Spectrochimica Acta Part B: Atomic Spectroscopy》1984,39(4):559-566
ICP torches are essentially unique devices. They are by necessity hand-made items. Therefore each has small variations in shape which cause individual differences in plasma configuration. As a consequence, utilization of an external reference point such as the “top of the load coil” is not adequate. It is well documented that ICP sources are complex and that different excitation mechanisms come into play in different parts of the source. This is demonstrated by the fact that generally atomic transitions have their peak intensities lower in the plasma, whereas ionic transitions peak higher in the plasma. The height-intensity relationship of both atomic and ionic species has been investigated. The use of the intersection of normalized atomic and ionic emission intensity profiles as a function of observation height has been evaluated as a possible internal reference point. This point is shown to be reproducible and easy to measure. 相似文献
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T. Armstrong M. Baubillier J.C. Brient W. Beusch I.J. Bloodworth G. Boca M. Bonesini D. Bortoletto A. Burns J.N. Carney G. Cecchet G. Costa C. Evangelista B. Ghidini J.B. Kinson V. Lenti L. Mandelli F. Navach R. Zitoun 《Nuclear Physics B》1983,224(2):193-217
Results from the first PWA of the K+K? system produced by incident K?, are presented in the mass range from the threshold to 1.70 GeV. In the P and D waves only the φ and f′ mesons are observed and their production mechanism studied. A broad S wave peaking at 1.4 GeV is observed but the lack of information about its phase makes the search for new 0++ mesons inconclusive. 相似文献
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Bismuth (0–120 μg) is determined spectrophotometrically at 495 nm after extraction as 1-naphthylmethyltriphenylphosphonium tetraiodobismuthate(III) into dichloromethane. The effects of diverse ions and masking studies are reported. The system is applied to the determination of bismuth in a range of copper-base alloys. 相似文献