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We compute constrained equilibria satisfying an optimality condition. Important examples include convex programming, saddle problems, noncooperative games, and variational inequalities. Under a monotonicity hypothesis we show that equilibrium solutions can be found via iterative convex minimization. In the main algorithm each stage of computation requires two proximal steps, possibly using Bregman functions. One step serves to predict the next point; the other helps to correct the new prediction. To enhance practical applicability we tolerate numerical errors. Research supported partly by the Norwegian Research Council, project: Quantec 111039/401.  相似文献   
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The experimental achievements and the results obtained so far with the LPCTrap device installed at GANIL are presented. The apparatus is dedicated to the study of the weak interaction at low energy by means of precise measurements of the β ? ν angular correlation parameter in nuclear β decays. So far, the data collected with three isotopes have enabled to determine, for the first time, the charge state distributions of the recoiling ions, induced by shakeoff process. The analysis is presently refined to deduce the correlation parameters, with the potential of improving both the constraint deduced at low energy on exotic tensor currents (6He1+) and the precision on the V u d element of the quark-mixing matrix (35Ar1+ and 19Ne1+) deduced from the mirror transitions dataset.  相似文献   
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High-spin states in 181Ta have been studied via the 176Yb(11B,α2n) reaction at 52 MeV using the PEX array and at 57 MeV using the NORDBALL array, with α-particle detection. The previously known, Kπ=(7/2)+ ground state band and Kπ=(9/2) band have been extended to spins (29/2)+ and (31/2), respectively. Two new one-quasiparticle bands, the Kπ=(5/2)+ band built on the known (5/2)+ isomer and a Kπ=((1/2)) band have been observed. Two other rotational bands with three-quasiparticle structure, Kπ=(15/2) and ((19/2)+ with π(7/2)[404]ν2(1/2)[510](9/2)[624] and π(9/2)[514]ν2(1/2)[510](9/2)[624] configurations, respectively, have been newly observed. The half-life of the Kπ=((19/2)+) bandhead which decays to the head of the (15/2) band has been measured to be 140(36) ns. However, transitions from the ((19/2)+) state to the (15/2) band have not been observed. Received: 26 August 1998  相似文献   
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High-spin states in 163Lu have been investigated using the Euroball spectrometer array. The previously known superdeformed band has been extended at low and high energies, and its connection to the normal-deformed states has been established. From its decay the mixing amplitude and interaction strength between superdeformed and normal states are derived. In addition, a new band with a similar dynamic moment of inertia has been found. The experimental results are compared to cranking calculations which suggest that the superdeformed bands in this mass region correspond to shapes with a pronounced triaxiality (γ≈±20°).  相似文献   
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We report on optical parametric oscillators (OPO's) based on periodically poled RbTiOAsO(4) (PP RTA), which are pumped by Q -switched solid-state lasers. With a diode-pumped Nd:YVO(4) laser (pulse energy, 800microJ ; pulse duration, 5.5 ns; repetition rate, 1 kHz) the PP RTA OPO generated 1.58-microm signal and 3.26-microm idler radiation with a signal pulse energy of 45microJ . The large aperture of 3 mmx3 mm of the PP RTA crystal also permitted OPO operation with pump pulse energies as high as 65 mJ, provided by a flash-lamp-pumped Q -switched Nd:YAG laser (pulse duration, 20 ns; repetition rate, 10 Hz). With this pump source the OPO generated signal pulse energies as high as 17 mJ, corresponding to an efficiency of 26%. The performance of this OPO shows that large-aperture PP RTA crystals are well suited for pulsed nanosecond OPO operation with pump pulse energies of tens of millijoules.  相似文献   
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Journal of Russian Laser Research - We consider even and odd coherent states (Schrödinger cat states) in the probability representation of quantum mechanics. The probability representation of...  相似文献   
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The formation of (TixW1–x)Si2/(TixW1–x)N, by rapid thermal processing of TixW1–x on Si in an N2 ambient is investigated. An activation energy of 1.7 eV is obtained for silicide formation. A distinct snow-ploughing of As atoms is observed during silicide formation whereas the interfacial B concentration decreases with increasing silicide formation temperature. The diffusion barrier properties of the (TixW1–x)Si2/(TixWi1–x)N stack in contact with Al is investigated upon post-metal annealing. No interaction between the layers is found for temperatures as high as 475°C after 60 min. The improved thermal stability of the (TixW1–x)N layer in contact with Al is attributed to nitrogen blocking of the grain boundaries.  相似文献   
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