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211.
A theoretical framework has been proposed to study patternsof innovation diffusion in a heterogeneous population, withapplicability to a number of problem areas including marketing.The heterogeneity in the population is captured through randomlyvarying parameters, which have been modelled in terms of two-pointdistributions. The effect of heterogeneity leads to the generationof bi-modal life cycle patterns besides the conventional uni-modalpattern resulting from S-shaped curve. The stochastic evolutionof the mean and variance of the number of adopters is foundto depict a high level of relative fluctuation around the pointof inflexion. As a result of randomness in parameters, the resultingdifferential equation for the evolution of the mean of the adoptionprocess is characterized by a non-autonomous system having parameterswhich are no longer constant but become time dependent. Fordemonstrating the effectiveness of the proposed framework, areal data set which depicts a bi-modal life cycle curve is investigated.The fit is found to be extremely good while capturing appropriateproduct life cycle curve.  相似文献   
212.
Recent experimental data on 125I has revealed several interesting structural features. These include the observation of a three quasiparticle band, prolate and oblate deformed bands, signature inversion in the yrast positive-parity band and identification of the unfavoured πh 11/2 band showing very large signature splitting. In the present work, particle-rotor-model calculations have been performed for the πh 11/2 band, using an axially symmetric deformed Nilsson potential. The calculations reproduce the experimental results well and predict a moderate prolate quadrupole deformation of about 0.2 for the band.  相似文献   
213.
214.
Journal of Thermal Analysis and Calorimetry - Lithium aluminum germanium phosphate glass–ceramics with NASICON structure find potential application in the field of energy storage...  相似文献   
215.

A simple and complete solution to determine the distributions of queue lengths at different observation epochs for the model GIX/Geo/c/N is presented. In the past, various discrete-time queueing models, particularly the multi-server bulk-arrival queues with finite-buffer have been solved using complicated methods that lead to results in a non-explicit form. The purpose of this paper is to present a simple derivation for the model GIX/Geo/c/N that leads to a complete solution in an explicit form. The same method can also be used to solve the GIX/Geo/c/N queues with heavy-tailed inter-batch-arrival time distributions. The roots of the underlying characteristic equation form the basis for all distributions of queue lengths at different time epochs. All queue-length distributions are in the form of sums of geometric terms.

  相似文献   
216.
We give a new method for proving the homomorphic property of a quantum stochastic flow satisfying a quantum stochastic differential equation with unbounded coefficients, under some further hypotheses. As an application, we prove a Trotter product formula for quantum stochastic flows and obtain quantum stochastic dilations of a class of quantum dynamical semigroups generalizing results of Goswami et al. (Inst H Poincare Probab Stat 41:505–522, 2005).  相似文献   
217.
Imbalance of zinc ion (Zn2+) in human body causes diseases like Alzheimer’s and Parkinson’s and therefore Zn2+ estimation in biological fluids has diagnostic values. Fluorescence “off-on” sensors have advantages of high sensitivity and in situ application over other sensors. A new fluorescent “off-on” Zn2+ sensor, N-benzoate-N′ salicylaldehyde ethynelediamine (L), has been synthesisied. In 1:1(v/v) CH3OH:PBS (PBS?=?phosphate buffer solution), L shows ca. 20 times enhancement in fluorescence intensity on interaction with Zn2+, due to snapping of photoinduced electron transfer (PET) process, which is selective over metal ions - Na+, K+, Ca2+, Ni2+, Cu2+, Cd2+, Hg2+ and Pb2+. These metal ions either individually or all together does not interfere the sensing ability of L towards Zn2+. A 1:1 interaction between L and Zn2+ ion with binding constant 104.25 has been established from spectroscopic data.  相似文献   
218.
The purpose of the present paper is to introduce several new classes of p-valent meromorphic functions defined by Ruscheweyh derivative operator for meromorphic multivalent functions. Further, we investigate the radii problems of these analytic classes in the punctured unit disk.  相似文献   
219.
Synthesis of structurally novel and biologically useful 3′-substituted diaryl ethers employing Cu(0) as a catalyst, followed by regioselective either sulfonylation or carbonylation, is described.  相似文献   
220.
A novel fluorescent probe for the copper(II) ion in mixed aqueous media, based on fluorescence quenching mechanism with noticeable color change from light to dark yellow, was designed and synthesized. It also exhibited high selectivity for acetate in acetonitrile over other common anions in the near infrared region (NIR) accompanied with exciting color changes from light yellow to pink. Hence sensor 1 ascertains its dual chemosensing ability toward Cu(II) and acetate ions as evidenced by competitive experiments.  相似文献   
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