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131.
132.
R. M. Sardarly O. A. Samedov I. Sh. Sadykhov V. A. Aliev 《Physics of the Solid State》2003,45(6):1118-1121
The relaxor properties of Fe-doped TlInS2 crystals are investigated. It is shown that Fe-doped TlInS2 compounds exhibit all features inherent in relaxor ferroelectric materials. The temperature range of existence of the microdomain (relaxor) state and the temperature of the transition from this state to a macro-domain state are determined. 相似文献
133.
The classical economic order quantity (EOQ) model assumes that items produced are of perfect quality and that the unit cost of production is independent of demand. However, in realistic situations, product quality is never perfect, but is directly affected by the reliability of the production process. In this paper, we consider an EOQ model with imperfect production process and the unit production cost is directly related to process reliability and inversely related to the demand rate. In addition, a numerical example is given to illustrate the developed model. Sensitivity analysis is also performed and discussed. 相似文献
134.
135.
We prove that the sufficient conditions for the asymptotic stability of impulsive systems obtained by Gurgula and Perestyuk are also necessary conditions. 相似文献
136.
A pseudopotential depending on an effective core radius is proposed to study the binding energy, equation of state, ion-ion
interaction, phonon dispersion curves (q-space and r-space analysis), mode Grüneisen parameters and dynamical elastic constants
of some fcc f-shell metals La, Yb, Ce and Th. The contribution of the s-like electrons is calculated in the second-order perturbation
theory for the potential while d and f-like electron is taken into account by introducing repulsive short-range Born-Mayer
term. The parameter of the potential is evaluated by zero pressure condition. An excellent agreement between theoretical investigations
and experimental findings is achieved which confirms the present formalism 相似文献
137.
Makarov V. L. Khlobystov V. V. Kashpur E. F. Mikhal'chuk B. R. 《Ukrainian Mathematical Journal》2003,55(6):942-955
We construct an integral Newton-type interpolation polynomial with a continual set of nodes. This interpolant is unique and preserves an operator polynomial of the corresponding degree. 相似文献
138.
Synchronized whistlers recorded at Varanasi 总被引:1,自引:0,他引:1
Some interesting events of synchronized whistlers recorded at low latitude station Varanasi during magnetic storm period of
the year 1977 are presented. The dynamic spectrum analysis shows that the component whistlers are Eckersley whistlers having
dispersion 10 s1/2 and 30 s1/2. An attempt has been made to explain the dynamic spectra using lightning discharge generated from magnetospheric sources 相似文献
139.
B. G. Tagiev U. F. Kasumov N. N. Musaeva R. B. Dzhabbarov 《Physics of the Solid State》2003,45(3):426-432
The current-voltage characteristics of Ca4Ga2S7: Eu3+ single crystals are measured for the first time, and the processes affecting these characteristics are analyzed theoretically. It is demonstrated that Ca4Ga2S7: Eu3+ single crystals are high-resistance semiconductors with a resistivity of ~109 Ω cm and a relative permittivity of 10.55. The electrical properties of the studied materials are governed by traps with activation energies of 0.13 and 0.19 eV and a density ranging from 9.5×1014 to 2.7×1015 cm?3. The one-carrier injection is observed in weak electric fields. In electric fields with a strength of more than 4×103 V/cm, traps undergo thermal field ionization according to the Pool-Frenkel mechanism. At low temperatures and strong fields (160 K and 5×104 V/cm), the electric current is most likely due to hopping conduction by charge carriers over local levels in the band gap in the vicinity of the Fermi level. 相似文献
140.