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131.
In this article we propose to partially integrate the antenna positioning (APP) and frequency allocation problems (FAP). The traditional wireless network design process examines these two major issues sequentially in order to avoid the very high complexity associated with the simultaneous resolution of the two problems. The proposed integration involves the introduction of interference protection guarantees within the APP. It is customary to define such guarantees in an intermediate step and to use them as input to FAP, in order to protect against interference in critical areas. The proposed approach consists of selecting these protections while solving the APP, allowing the optimization procedure to exploit the degrees of freedom that this would offer. Results on two real-life problem instances indicate a significant improvement in interference levels and resource utilization. 相似文献
132.
Samit Mandal J Gerl H Geissel K Hauschild M Hellström Z Janas I Kojouharov Y Kopatch RC Lemmon P Mayet Z Podolyak PH Regan H Schaffner C Schlegel J Simpson HJ Wollersheim 《Pramana》2001,57(1):161-164
Feasibility of gamma-ray spectroscopy at relativistic energies with exotic heavy-ions and new generation of germanium detectors
(segmented Clover) is discussed. An experiment with such detector array and radioactive is discussed. 相似文献
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The reactions of the hydroxyl radical (at low pH) and SO4−. have been employed to oxidize a number of phenyl-substituted alcohols in aqueous solution; ESR spectroscopy has been employed
to study directly the radicals formed by fragmentation of first-formed radical-cations. Examples of deprotonation (to give
benzyl radicals), Cα−Cβ bond scission (e.g. PhCH2CH2OH to PhCH2
.) and longer-range fragmentation (e.g. PhCH2CH2CMe2OH to PhCH2CH2
.) are described and discussed: evidence is obtained for intramolecular nucleophilic attack as a route for overall electron-transfer
from side-chain to aromatic ring. Solvation of the proton and of oxygen-conjugated carbonium ions is thought, at least in
part, to account for differences between fragmentations induced in the gaseous and aqueous phases. 相似文献
138.
I. Koppel L. Michaelis P. Rona C. Drucker W. Gerlach K. Jellinek P. Debye E. Sauter M. von Rohr Ch. Boehringer H. Dingler L. Gilbert und W. Kroll 《Fresenius' Journal of Analytical Chemistry》1931,83(5-6):188-190
Ohne Zusammenfassung 相似文献
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Values for 〈ΔEdown〉, the average downward energy transferred from the reactant to the bath gas upon collision, have been obtained for highly vibrationally excited undeuterated and per-deuterated isopropyl bromide with the bath gases Ne, Xe, C2H4, and C2D4, at ca. 870 K. The technique of pressure-dependent very low-pressure pyrolysis (VLPP) was used to obtain the data. For C3H7Br, the 〈ΔEdown〉 values (cm?1) are 490 (Ne), 540 (Xe), 820 (C2H4), and 740 (C2D4), and for C3D7Br, 440 (Ne), 570 (Xe), 730 (C2H4), and 810 (C2D4). The uncertainties in these values are ca. ±10%. The 〈ΔEdown〉 values for the inert bath gases Ne and Xe show excellent agreement with the theoretical predictions of the semi-empirical biased random walk model for monatomic/substrate collisional energy exchange [J. Chem. Phys., 80 , 5501 (1984)]. The relative effects of deuteration of the reactant molecule on 〈ΔEdown〉 also compare favorably with the predictions of this theoretical model. Extrapolated high-pressure rate coefficients (s?1) for the thermal decomposition of reactant are 1013.6±0.3 exp(?200 ± 8 kJ mol?1/RT) for C3H7Br and 1013.9±0.3 exp(?207 ± 8 kJ mol±1/RT) for C3D7Br, which are consistent with previous studies and the expected isotope effect. 相似文献