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81.
Inventory of differential (both good and defective) items purchased in a lot for two shops under a single management is considered here. In the primary shop, the lot is received and separated, only good units are sold and shortages are allowed which are backlogged from the good units specially purchased at the beginning of the next cycle. The separated defective units are continuously trasnsferred and sold at a reduced price from the secondary shop. This inventory model is formulated and illustrated numerically for three scenarios depending upon the time periods of the shops. 相似文献
82.
83.
Debajyoti Bhaumik Kamales Bhaumik Binayak Dutta-Roy Meher H. Engineer 《Physics letters. A》1977,62(3):197-200
The system consists of an electric polarisation field coupled on the one hand to an elastic field and on the other to a thermal reservoir. When the polarisation modes are pumped, Bose condensation in the lowest mode occurs, for energy inflow above a certain critical amount. It is shown that elastic forces, called into play to stabilise the excitation of the polar modes, lowers the threshold for Bose condensation. With further increase in the pumping rate the possibility exists for the softening of the polarisation oscillations leading, in the presence of quartic self-interaction of the polarisation field (inserted for stability), to a metastable ferroelectric state. The work represents an attempt to develop a microscopic approach to the Fröhlich model for the dynamics of macromolecules (such as proteins and enzymes) of biological significance. 相似文献
84.
P. F. Moulton W. Künzel U. Dürr A. Beimowski G. Huber D. Pruss V. V. Laptev I. A. Shcherbakov Y. V. Zharikov B. Struve J. M. Eggleston T. Kane R. L. Byer J. Unternahrer R. G. Harrison M. R. Taghizadeh A. K. Kar P. K. Gupta D. J. Jackson J. J. Wynne J. J. Rocca J. D. Meyer Zeng-qi Yu G. J. Collins 《Applied physics. B, Lasers and optics》1982,28(2-3):233-239
85.
The local-field correction near the surface of a dipolar crystal has been studied by explicitly computing the non-retarded electric field produced by a finite array of classical point dipoles induced by a time-varying electric field. Crystals of simple cubic, f.c.c. and b.c.c. structures are considered, and results presented for the self-consitent dipole moment and the local electric field at a lattice point. The utility of the method and its possible applications are discussed. 相似文献
86.
87.
The weak objectification and Bell/CHSH inequalities are studied for a particular type of set of states of two spin-1/2 particles.
The restriction on interference term which allows Bell/CHSH inequalities to be satisfied are found out. 相似文献
88.
S. Kar Y. K. Ho 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,57(1):13-19
The doubly excited 1,3D○ resonance states of Ps- associated
with N=3, N=4 and N=5 Ps thresholds have been investigated using highly
accurate correlated wave functions with exponents generated by a quasirandom
process. Resonance parameters (both resonance positions and widths) are
extracted in the framework of the stabilization method and the complex
coordinate rotation method. In addition to many Feshbach resonances below
the various Ps thresholds, we have identified two 1
D○ shape
resonances with one each lying above the N=3 and N=4 thresholds, respectively,
and two 3
D○ shape resonances with one each lying above the N=3 and
N=5 thresholds, respectively. The 1
D○ shape resonance associated
with N=3 Ps threshold and some other Feshbach resonances are reported for the
first time in the literature. 相似文献
89.
Chakraborty A Kar S Nath DN Guchhait N 《The journal of physical chemistry. A》2006,110(44):12089-12095
A donor-acceptor substituted aromatic system (E)-3-(4-Methylamino-phenyl)-acrylic acid methyl ester (MAPAME) has been synthesized, and its photophysical behavior obtained spectroscopically has been compared with the theoretical results. The observed dual fluorescence from MAPAME has been assigned to emission from locally excited and twisted intramolecular charge transfer states. The donor and acceptor angular dependency on the ground and excited states potential energy surfaces have been calculated both in vacuo and in acetonitrile solvent using time dependent density functional theory (TDDFT) and TDDFT polarized continuum model (TDDFT-PCM), respectively. Calculation predicts that a stabilized twisted excited state is responsible for red shifted charge transfer emission. 相似文献
90.
Tapan Kuman Kar K. S. Chaudhuri 《International Journal of Mathematical Education in Science & Technology》2013,44(4):543-556
The present paper deals with the problem of non-selective harvesting of a prey-predator system in which both the prey and the predator species obey the law of logistic growth and each predators functional response to the prey approaches a constant as the prey population increases. Boundedness of the exploited system is examined. The existence of its steady states and their stability are studied using eigenvalue analysis. The existence of bionomic equilibria has been considered. The problem of determining the optimal harvest policy is then solved by using Pontryagin's maximal principle. Finally, some numerical examples are given to illustrate the results. 相似文献