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91.
Polyion complex micelles entrapping enzyme molecules in the core provide a unique reaction field inducing a remarkable elevation of enzymatic reactivity through a drastic change in the binding specificity between the enzyme and substrate. On-off switching of this enhanced effect was achieved through the destabilization of the core domain by applying a pulse electric field. 相似文献
92.
K. Harada H. Kuratsuji 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,59(2):193-198
We study a dynamics of texture for a two-component spinor bose condensate.
This is carried out by adopting a time dependent Landau-Ginzburg Lagrangian for
a spinor order parameter. By using a polar form of the spinor order parameter, we obtain
a field equation for the texture. In particular we consider a one dimensional model in which we can obtain analytic forms
for the textures in terms of elliptic functions of several kinds.
We find that these solutions are characterized by a modulus parameter, and changes in this parameter cause structural changes
of texture. 相似文献
93.
94.
J A Meriluoto J E Eriksson K Harada A M Dahlem K Sivonen W W Carmichael 《Journal of chromatography. A》1990,509(2):390-395
95.
A stochastic model is developed describing a service system subject to inhomogeneous Poisson interruptions with age dependent interruption periods. By studying the probabilistic flow of the underlying multivariate Markov process, the Laplace transform of the effective service time is explicitly obtained. For general renewal interruptions, only the expected effective service time is derived. As an application, an optimal checkpoint policy is examined for database management. It is shown that an optimal policy maximizing the ergodic availability of the database is to implement a checkpoint as soon as the cumulative uptime of the database reaches a prespecified constantk
*. A computational procedure is then developed for findingk
* and numerical results are exhibited.This work was supported in part by the National Science Foundation under Grant No. ECS-8600992 and by the IBM Program of Support for Education in the Management of Information Systems. 相似文献
96.
97.
Yoshimi Yamaguchi Yoshihisa Okamoto Kazuho Harada 《Journal of heterocyclic chemistry》1999,36(4):841-847
The revision of the structure of hydrolytic product from 4-cyano-1-ethoxypyrirnido[1,6-a]benzimidazole (1) and the properties of ethyl (2-benzimidazolyl)cyanoacetimidate (3a) are described. 相似文献
98.
In CRM (Customer Relationship Management), the importance of a segmentation method for identifying good customers has been increasing. For evaluation of different segmentation methods, Accuracy often plays a key role. This indicator, however, cannot distinguish two types of errors. The purpose of this paper is to overcome this pitfall by introducing two different indicators: Recall and Precision. Assuming that a promotion is addressed exclusively to the selected target customers, the financial effectiveness of the underlying segmentation method is expressed as a function of Recall and Precision. An optimization problem is then formulated so as to maximize the financial measure by finding the optimal threshold level in terms of the severeness for estimating the target set. By introducing a functional form which represents correctness and mistakes about the target set, the unique optimal solution is derived explicitly. The proposed approach is validated by using real customer purchase data. 相似文献
99.
100.