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排序方式: 共有10000条查询结果,搜索用时 9 毫秒
991.
992.
993.
The open mapping and closed range theorems 总被引:1,自引:0,他引:1
994.
995.
The design of nonlinear, time varying, multivariable, coupled system is a complicated task which offers few intuitive guides. Such guides are by contrast abundant in the much simpler task of designing a linear decoupled control system. Decoupling also allows the independent control of the system outputs in the presence of input interactions. The implications of these ideas in the design of control systems for continuous drug infusion have never been explored. This tutorial demonstrates the usefulness of nonlinear decoupling in the context of drug delivery using simple examples. First, decoupling by differentiation of the output equation is demonstrated. Next, two special cases where decoupling is achievable by input redefinition ann by input and state redefinition are given. Finally, limitations of the approach are discussed together with ongoing research to overcome them. The presentation avoids complex mathematical derivations and demonstrates that nonlinear decoupling can be applied using basic calculus. 相似文献
996.
P. S. Goyal 《Pramana》2004,63(1):15-24
Inter University Consortium for Department of Atomic Energy Facilities (IUC-DAEF) is an autonomous institute of the University
Grants Commission and provides an interface between the university fraternity and the institutions of Department of Atomic
Energy. Mumbai Centre of IUC-DAEF promotes and supports the use of neutron facilities at Dhruva reactor by the university
scientists. To augment the existing neutron scattering facilities, IUC-DAEF has developed a neutron beam line at Dhruva reactor.
The present paper gives a brief survey of the activities and achievements of Mumbai Centre of IUC-DAEF. 相似文献
997.
998.
T. V. Ramakrishnan H. R. Krishnamurthy S. R. Hassan G. Venketeswara Pai 《Journal of Chemical Sciences》2003,115(5-6):767-774
Manganites of the LA1−x
Ca
x
MnO3 family show a variety of new and poorly understood electronic, magnetic and structural effects. Here we outline a new approach
recently proposed by us, where we argue that due to strong Jahn-Teller (JT) coupling with phonons the twofold degeneratee
g
states at the Mn sites dynamically reorganize themselves into localised, JT polaronsl with exponentially small inter-site hopping, and band-like, nonpolaronic statesb, leading to anew 2-band model for manganites which includes strong Coulomb and Hund’s couplings. We also discuss some results from a dynamical mean-field theory treatment
of the model which explains quantitatively a wide variety of experimental results, including insulator-metal transitions and
CMR, in terms of the influence of physical conditions on the relative energies and occupation of thel andb states. We argue that this microscopic coexistence of the two types of electronic states, and their relative occupation and
spatial correlation is the key to manganite physics.
Dedicated to Professor C N R Rao on his 70th birthday 相似文献
999.
1000.
S. B. Kuksin 《Proceedings of the Steklov Institute of Mathematics》2007,259(1):128-136
We discuss the inviscid limits for the randomly forced 2D Navier-Stokes equation (NSE) and the damped/driven KdV equation.
The former describes the space-periodic 2D turbulence in terms of a special class of solutions for the free Euler equation,
and we view the latter as its model. We review and revise recent results on the inviscid limit for the perturbed KdV and use
them to suggest a setup which could be used to make a next step in the study of the inviscid limit of 2D NSE. The proposed
approach is based on an ergodic hypothesis for the flow of the 2D Euler equation on iso-integral surfaces. It invokes a Whitham
equation for the 2D Navier-Stokes equation, written in terms of the ergodic measures. 相似文献