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921.
Francesc Carreras M. Dolors Llongueras Antonio Magaña 《Annals of Operations Research》2005,137(1):67-89
A partnership in a cooperative game is a coalition that possesses an internal structure and, simultaneously, behaves as an
individual member. Forming partnerships leads to a modification of the original game which differs from the quotient game
that arises when one or more coalitions are actually formed.
In this paper, the Shapley value is used to discuss the convenience to form either coalitions or partnerships. To this end,
the difference between the additive Shapley value of the partnership in the partnership game and the Shapley alliance value
of the coalition, and also between the corresponding value of the internal and external players, are analysed. Simple games
are especially considered.
Research partially supported by Grant BFM 2003-01314 of the Science and Technology Spanish Ministry and the European Regional
Development Fund. 相似文献
922.
923.
924.
A. L. Goldenberg V. N. Manuilov M. Yu. Glyavin 《Radiophysics and Quantum Electronics》2005,48(6):461-465
We describe a nonadiabatic electron gun operated in the mode of a currentconfined by spatial charge and intended for producing
helical electron beams for high-power gyroresonantdevices.Results of numerical simulation of electron trajectories and electron-beam
parameters arepresented. It is shown that for a high operating current, the pitch factor and the electronvelocity spread can
be significantly better than in the conventional adiabatic systems.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 48,No. 6, pp. 517–522, June 2005 相似文献
925.
V. L. Gilyarov A. I. Slutsker V. P. Volodin L. A. Laius 《Physics of the Solid State》1997,39(1):132-135
The dependence of the energy characteristics on an adiabatically slowly increasing external force is determined analytically
for an anharmonic oscillator. The analytical results are confirmed by a numerical calculation. The nature of the force dependences
of the energy characteristics are determined and discussed.
Fiz. Tverd. Tela (St. Petersburg) 39, 153–157 (January 1997) 相似文献
926.
The yield and energy distributions of potassium and cesium atoms emitted in electron-stimulated desorption (ESD) from a molybdenum
surface, oxidized to different extent and maintained at 300 K, have been measured by the time-of-flight technique with a surface
ionization detector. The ESD threshold for potassium and cesium atoms lies around 25 eV, irrespective of molybdenum oxidation
state. In the case of molybdenum coated by an oxygen monolayer, secondary thresholds at ∼40 and ∼70 eV have been observed,
as well as atomic energy distribution tailing down to very low energies. The most probable kinetic energies of the atoms are
a few tenths of one eV. The results are explained within a model involving Auger neutralization of the adsorbed alkali metal
ions after the filling of the 2s O, 4s Mo, and 4p Mo core holes. The possibility of ESD of a neutral species as a result of oxide-cation core-level ionization has been demonstrated
for the first time.
Fiz. Tverd. Tela (St. Petersburg) 39, 758–761 (April 1997) 相似文献
927.
Consideration is given to the special features of the excitation of spectra of metals (Ag, Au, Fe, Hg, Pt, and Sb) that manifest
themselves in investigating spectral sources with combined glow discharge (glow discharge and capillary discharge). It is
established that the proposed method for introducing a substance into a plasma makes it possible to realize two fundamentally
different regimes: without evaporation and with complete evaporation and matrix atomization. It is shown that a spectral source
of combined glow discharge with a nonequilibrium plasma has significant advantages for the most important analytical characteristics
over quasi-equilibrium combined discharge at atmospheric pressure. The gold and platinum sensitivity in combined glow discharge
is 10−7%, and the reproducibility of spectral determinations is 0.001–0.100, depending on the measurement range. A fractional separation
of elements that makes it possible to analyze the phase composition of substances, particularly metals, with high sensitivity
is revealed in glow discharge.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 2, pp. 143–147, March–April, 1997. 相似文献
928.
New effects are observed wherein the internal structure of the domain walls in a thin magnetic iron garnet film are modified
by the action of focused laser radiation. A single laser pulse with increasing power gives rise to the following: 1) displacement
of vertical Bloch lines in a domain wall; 2) generation of a pair of vertical Bloch lines on initially line-free walls; and,
3) an irreversible change in shape of a domain wall and the domain structure as a whole. The mechanism leading to the generation
and displacement of Bloch lines is connected with the motion of domain walls which is induced by a local change in the distribution
of demagnetizing fields as a result of a heating-induced decrease of the magnetization in the focal spot of the laser radiation.
Pis’ma Zh. éksp. Teor. Fiz. 66, No. 6, 398–402 (25 September 1997) 相似文献
929.
We study condensation of ethanol-hexanol vapour by numerical solution of kinetic equations. The number of droplets formed
in unit volume is computed within self-consistent classical model. It is shown that formation of ethanol-rich droplets prevails
at the initial stage of nucleation process, but in the stationary state formation of droplets near the saddle point (on cluster
formation energy surface) plays the dominant role.
Presented at the 6th Joint Seminar “Development of Materials Science in Research and Education”, Karlštejn, Czech Republic,
17–19 September 1996.
This work was supported by Grant No. A1010615 of the Grant Agency of the Academy of Sciences of the Czech Republic. 相似文献
930.
The diffuse scattering of x rays in a four-layer waveguide-type heterostructure is investigated. The dynamic enhancement of
diffuse scattering is detected experimentally in regions corresponding to the excitation of waveguide modes for both the incident
and scattered waves.
Pis’ma Zh. éksp. Teor. Fiz. 66, No. 4, 219–223 (25 August 1997) 相似文献