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41.
Work on capacity design for VP restoration in ATM has to date either been heuristic in nature or has treated the capacity design problem in a 1 for 1 VP replacement manner that is essentially the same as for STM path restorable networks. However, the inherently statistical nature of the traffic in ATM should allow formulation of a backup VP restoration capacity design that permits a controlled maximum of convergent flow overloads on spans during restoration. Results show that significant capacity savings can be obtained relative to STM if ATM restoration is allowed even modest restoration overload factors. We give an integer program formulation permitting controlled exploitation of this intrinsic difference between ATM and STM transport and present results showing the significant capacity benefits motivating this approach 相似文献
42.
V. Hejny J. Weiß P. Achenbach J. Ahrens J.R.M. Annand R. Beck M. Kotulla B. Krusche V. Kuhr R. Leukel I.J.D. MacGregor V. Metag R. Novotny V. Olmos de León F. Rambo A. Schmidt M. Schumacher U. Siodlaczek H. Ströher F. Wissmann M. Wolf 《The European Physical Journal A - Hadrons and Nuclei》2002,13(4):493-499
The photoproduction of η-mesons from 2H and 4He has been studied for energies close to the production thresholds. The experiments were carried out with the tagged photon
beam of the Mainz MAMI accelerator. The η-mesons were detected via their two photon decays with the electromagnetic calorimeter
TAPS. Total cross-sections, angular and momentum distributions of the η-mesons have been determined for both reactions. The
total cross-sections in the threshold region show a large enhancement over the predictions of a participant-spectator model,
indicating significant final-state interaction effects. The results are compared to recent model calculations taking into
account nucleon-nucleon and nucleon-η final-state interaction effects on different levels of sophistication.
Received: 23 November 2001 / Accepted: 11 February 2002 相似文献
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44.
In this paper, we examine a class of nonlinear, stochastic knapsack problems which occur in manufacturing, facility or other network design applications.Series, merge-and-split topologies of series-parallelM/M/1/K andM/M/C/K queueing networks with an overall buffer constraint bound are examined. Bounds on the objective function are proposed and a sensitivity analysis is utilized to quantify the effects of buffer variations on network performance measures. 相似文献
45.
R. Wichmann J. Ahrens H. J. Arends R. Beck G. Galler A. Hünger A. Kraus I. J. D. MacGregor J. Peise B. Seitz M. Schmitz M. Schneider O. Selke M. Schumacher F. Wissmann 《Zeitschrift für Physik A Hadrons and Nuclei》1974,355(2):169-177
High resolution proton energy spectra from the 4He(γ,p) reaction have been measured with tagged photons in the range Eγ = 130–525 MeV using the large Mainz NaI(Tl) spectrometer at \([Theta _p^{lab} = 37.1^circ ]\) . Three separate reaction channels were identified, viz. 4He(γ,p)t two-body breakup, 4He photodisintegration via two-nucleon photon absorption processes and the quasifree pion production channel. Differential cross sections are presented for each of these channels as a function of photon energy. The sum of the two-nucleon photon absorption and the quasifree pion production differential cross sections, in the CM system, resembles that of the corresponding free-nucleon differential cross section when Fermi motion is taken into account. 相似文献
46.
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49.
J. Ahrens V. M. Alexeev J. R. M. Annand H. J. Arends R. Beck G. Caselotti S. N. Cherepnya D. Drechsel L. V. Fil’kov K. Föhl I. Giller P. Grabmayr T. Hehl D. Hornidge V. L. Kashevarov M. Kotulla D. Krambrich B. Krusche M. Lang J. C. McGeorge I. J. D. MacGregor V. Metag M. Moinester R. Novotny M. Pfeiffer M. Rost S. Schadmand S. Scherer A. Thomas C. Unkmeir Th. Walcher 《The European Physical Journal A - Hadrons and Nuclei》2005,23(1):113-127
An experiment on the radiative {+}-meson photoproduction from the proton ( p {+}n) was carried out at the Mainz Microtron MAMI in the kinematic region 537MeV < E < 817MeV, 140°
180°. The {+}-meson polarizabilities have been determined from a comparison of the data with the predictions of two different theoretical models, the first one being based on an effective pole model with pseudoscalar coupling while the second one is based on diagrams describing both resonant and nonresonant contributions. The validity of the models has been verified by comparing the predictions with the present experimental data in the kinematic region where the pion polarizability contribution is negligible ( s1 < 5m2) and where the difference between the predictions of the two models does not exceed 3%. In the region, where the pion polarizability contribution is substantial ( 5 < s1/m2 < 15, -12 < t/m2 < - 2), the difference
of the electric () and the magnetic () polarizabilities has been determined. As a result we find
. This result is at variance with recent calculations in the framework of chiral perturbation theory. 相似文献
50.
Thomas H. MacGregor 《Journal of Mathematical Analysis and Applications》2003,282(1):163-176
We consider Hadamard products of power functions P(z)=(1−z)−b with functions analytic in the open unit disk in the complex plane, and an integral representation is obtained when 0<Reb<2. Let where μ is a complex-valued measure on the closed unit disk Such sequences are shown to be multipliers of Hp for 1?p?∞. Moreover, if the support of μ is contained in a finite set of Stolz angles with vertices on the unit circle, we prove that {μn} is a multiplier of Hp for every p>0. When the support of μ is [0,1] we get the multiplier sequence which provides more concrete applications. We show that if the sequences {μn} and {νn} are related by an asymptotic expansion