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141.
We introduce a trust region algorithm for minimization of nonsmooth functions with linear constraints. At each iteration,
the objective function is approximated by a model function that satisfies a set of assumptions stated recently by Qi and Sun
in the context of unconstrained nonsmooth optimization. The trust region iteration begins with the resolution of an “easy
problem”, as in recent works of Martínez and Santos and Friedlander, Martínez and Santos, for smooth constrained optimization.
In practical implementations we use the infinity norm for defining the trust region, which fits well with the domain of the
problem. We prove global convergence and report numerical experiments related to a parameter estimation problem.
Supported by FAPESP (Grant 90/3724-6), FINEP and FAEP-UNICAMP.
Supported by FAPESP (Grant 90/3724-6 and grant 93/1515-9). 相似文献
142.
Guido Montagna Mauro Moretti Oreste Nicrosini Fulvio Piccinini 《The European Physical Journal C - Particles and Fields》1998,2(3):483-496
The production of an intermediate-mass Higgs boson in processes of the kind fermions at the energies of future linear colliders is studied. The recently developed and fully automatic algorithm/code
ALPHA is used to compute the tree-level scattering amplitudes for the reactions . The code has been interfaced with the Monte Carlo program HIGGSPV/WWGENPV, properly adapted to 6-fermion production, in order to provide realistic results, both in the form of cross sections and
event samples at the partonic level. Phenomenological results, that incorporate the effects of initial-state radiation and
beamstrahlung, are shown and commented, emphasizing the potentials of full six-fermion calculations for precise background
evaluation as well as for detailed studies of the fundamental properties of the Higgs particle.
Received: 22 May 1997 / Published online: 20 February 1998 相似文献
143.
G. Carelli A. De Michele M. Finotti K. Bousbahi N. Ioli A. Moretti 《International Journal of Infrared and Millimeter Waves》2003,24(5):799-811
Metal-semiconductor point contact diodes have proved to be good detectors and mixers for radiation from the far-infrared to visible. Until now GaAs, InSb and InP are the most studied and used semiconductor materials for these devices. In this work we present the performance in the visible and infrared region for metal-semiconductor point-contact diodes with GaSb or InAs as the semiconductor layers. These two new materials have shown good characteristics. 相似文献
144.
Francesco Caravaglios Mauro Moretti 《Zeitschrift fur Physik C Particles and Fields》1997,74(2):291-296
We apply the iterative numerical algorithm ALPHA, which automatically generates the N-point Green functions (as recently suggested [1]) to the computation of the production rate of four fermions and four fermions plus photon in electron-positron annihilation. The discussion of the physical results is preceded by an introduction on the algorithm. 相似文献
145.
F. Bonfigli B. Jacquier F. Menchini R. M. Montereali P. Moretti E. Nichelatti 《辐射效应与固体损伤》2013,168(1-6):185-190
Highly stable F2 color centers are very efficiently produced in lithium fluoride (LiF) by electron beam irradiation at room temperature. We have fabricated optical microcavities in which the active medium is a low-energy electron beam irradiated LiF film, whose optical thickness is comparable with the peak wavelength (~668nm) of the F2 broad photoluminescence band. By selecting the proper electron beam energy, one can control the F2 color center depth distribution. This distribution influences the photoemission angular distribution of the microcavity, whose resonance properties are determined by the coupling of the depth profile of the defects with the pump electromagnetic field and microcavity modes. 相似文献
146.
S. Tascu R. J. Reeves B. Jacquier P. Moretti R. M. Montereali M. Piccinini 《辐射效应与固体损伤》2013,168(6-12):691-694
Electron-beam lithography has been used to define color center stripes of about one hundred micrometers length and variable width (100 v nm to 5 v m) in lithium fluoride. These structures have for the first time been illustrated and spectrally characterized in near field optical microscopy (SNOM) operating in local illumination mode with an optical fiber probe and far field fluorescence detection. 相似文献
147.
Ari‐Pekka Honkanen Roberto Verbeni Laura Simonelli Marco Moretti Sala Giulio Monaco Simo Huotari 《Journal of synchrotron radiation》2014,21(1):104-110
Theoretical and experimental studies are presented on properties of spherically bent analyser crystals for high‐resolution X‐ray spectrometry. A correction to the bent‐crystal strain field owing to its finite surface area is derived. The results are used to explain the reflectivity curves and anisotropic properties of Si(660) and Si(553) analysers in near‐backscattering geometry. The results from the calculation agree very well with experimental results obtained using an inelastic X‐ray scattering synchrotron beamline. 相似文献
148.
Lorenzo Basso Alexander Belyaev Stefano Moretti Giovanni Marco Pruna Claire H. Shepherd-Themistocleous 《The European Physical Journal C - Particles and Fields》2011,71(4):1613
We present the Large Hadron Collider (LHC) discovery potential in the Z′ sector of a \(U(1)_{B\mbox{--}L}\) enlarged Standard Model (that also includes three heavy Majorana neutrinos and an additional Higgs boson) for \(\sqrt{s}=7\), 10 and 14 TeV centre-of-mass (CM) energies, considering both the \(Z'_{B\mbox{--}L}\rightarrow e^{+}e^{-}\) and \(Z'_{B\mbox{--}L}\rightarrow\mu^{+}\mu^{-}\) decay channels. The comparison of the (irreducible) backgrounds with the expected backgrounds for the DØ experiment at the Tevatron validates our simulation. We propose an alternative analysis that has the potential to improve the DØ sensitivity. Electrons provide a higher sensitivity to smaller couplings at small \(Z'_{B\mbox{--}L}\) boson masses than do muons. The resolutions achievable may allow the \(Z'_{B\mbox{--}L}\) boson width to be measured at smaller masses in the case of electrons in the final state. The run of the LHC at \(\sqrt{s}=7\) TeV, assuming at most \(\int\mathcal{L} \sim1\) fb?1, will be able to give similar results to those that will be available soon at the Tevatron in the lower mass region, and to extend them for a heavier M Z′. 相似文献
149.
Stefano Moretti 《The European Physical Journal C - Particles and Fields》2011,71(1):267-276
Both the reducible and irreducible backgrounds to the Higgs production channele + e ???H 0 Z 0 at a Next Linear Collider (NLC) are studied, for the Standard Model (L M) Higgs boson in the intermediate-mass range. A phenomenological analysis that does not exploit any form of tagging on the Higgs decay products is assumed. 相似文献
150.