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81.
R. Baldini-Celio M. Bozzo G. Capon R. Del Fabbro M. Grilli E. Iarocci M. Locci C. Mencuccuni G.P. Murtas M.A. Spano M. Spinetti V. Valente C. Bacci G. Penso B. Stella 《Physics letters. [Part B]》1975,58(4):471-474
The reactions e+e?→ hadrons and e+e+e?→e+e? have been studied at the J/gY (3100) resonance). The relative weights of the topological cross sections for fixed charged multiplicity are σ2=(32±5)%, σ4=(49±8)%, σ6=(18±3)%, and σ8=(1±0.6)%. The average pion multiplicities are 〈nch〉=3.8±0.3 and 〈nπo〉=3.1±0.8. The decay widths are Γe=(4.6±0.8) keV, Γh=(59±24) keV, and Γ=(68±26) keV. 相似文献
82.
Ferenc Szidarovszky Lucien Duckstein Istvan Bogardi 《European Journal of Operational Research》1984,15(2):251-258
The management of an aquifer is studied under the assumption that the solution of the multiobjective programming model describing the management problem should satisfy a certain set of axioms. It is shown that a certain class of multiobjective problems may be solved by a game-theoretical concept leading to a single objective quasiconvex programming problem. The method is generalization of Nash's cooperative game theoretical model, and may lean on Zeuther's bargaining process. The methodology is applied to the Transdanubian Karstic region in Hungary where three objectives are present: mining costs, water supply and environmental protection. Results are compared with the solution previously obtained by compromise programming with an l1-norm. It is found that results obtained by the two methods are comparable. 相似文献
83.
Maria Stella Mongioví Silvana Romeo 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1996,47(1):144-161
A dissipative model of helium II was built up in previous works, using a 13-field extended thermodynamic theory formulated by Liu and Müller. In this work a generalization of such model is presented, where an extended thermodynamics with 14 fields due to Kremer is used. It is shown that the fourteenth field is able to account for the experimental data concerning the second sound attenuation. Further, the proposed theory is able to explain the Osborne experiment. Finally, a comparison with the two-fluid model is performed, emphasizing the different ways in which the dissipative phenomena are explained by the two theories. 相似文献
84.
An extraction method is described for the determination of traces of tin in which crystal violet is used as complexing agent. 相似文献
85.
This paper shows that market equilibrium problems of production may generally be modelled as equilibrium flow problems in networks and that their equilibrium conditions can be visualized as a variational inequality. This connection would allow us to transplant directly elements of the well-developed theory of equilibrium flow in networks to the theory of market equilibrium. 相似文献
86.
87.
The problem of selecting the appropriate multiobjective solution technique to solve an arbitrary multiobjective decision problem is considered. Various classification schemes of available techniques are discussed, leading to the development of a set of 28 model choice criteria and an algorithm for model choice. This algorithm divides the criteria into four groups, only one of which must be reevaluated for each decision problem encountered. The model choice problem is itself modeled as a multiobjective decision problem—strongly influenced, however, by the individual performing the analysis. The appropriate technique is selected for implementation by use of the compromise programming technique. Two example problems are presented to demonstrate the use of this algorithm. The first is concerned with ranking a predefined set of river basin planning alternatives with multiple noncommensurate ordinally ranked consequences. The second deals with coal blending and is modeled by dual objective linear programming. An appropriate multiobjective solution technique is selected for each of these two examples. 相似文献
88.
A brief review of the ELECTRE II technique based on a strong and a weak ordinal outranking relationship is given. This technique, which is applied to alternative vegetation management schemes, leads to a complete ranking of the alternatives by means of three thresholds for concordance conditions and two thresholds for discordance conditions. Specifically, six alternative schemes are evaluated with respect to seven criteria, leading to the determination of a preferred system. A sensitivity analysis indicates that the ELECTRE II ranking is fairly robust with respect to parameter changes for the conditions of the case study. 相似文献
89.
90.
Stella M. Peltier A. Plastino E. S. Hernández 《Zeitschrift für Physik A Hadrons and Nuclei》1974,269(4):347-352
The relationship between collectivity and ground state correlations is analyzed for the single closed shell lead isotopes. The effects of the schematic approximation are discussed, within the framework of both the quasiparticle Random Phase Approximation and the quasiparticle Tamm-Dancoff approach. The consistency of the RPA is investigated. 相似文献