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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A method is considered to solve a conditional optimization problem with a linear-fractional objective function over permutations.
The performance of sub algorithms to solve this problem is evaluated. The practical efficiency of the algorithm is analyzed
by conducting numerical experiments.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 133–146, July–August 2007. 相似文献
992.
Cloning of observables, unlike standard cloning of states, aims at copying the information encoded in the statistics of a
class of observables rather then on quantum states themselves. In such a process the emphasis is on the quantum operation
(evolution plus measurement) necessary to retrieve the original information. We analyze, for qubit systems, the cloning of
a class generated by two noncommuting observables, elucidating the relationship between such a process and joint measurements.
This helps in establishing an optimality criterion for cloning of observables. We see that, even if the cloning machine is
designed to act on the whole class generated by two noncommuting observables, the same optimal performances of a joint measurement
can be attained. Finally, the connection with state dependent cloning is enlightened. 相似文献
993.
V. V. Evgrafov V. V. Pavlovsky V. E. Pavlovsky 《Journal of Computer and Systems Sciences International》2007,46(5):836-841
The problem of synthesizing trajectories, planning and implementing the motion of a mobile robot is investigated. The statement of the problem is motivated by the need for designing an optimal control of robots with two wheels controlled independently. Mobile robots with this kinematic scheme are called robots with “differential drive.” 相似文献
994.
995.
996.
E. P. Velikhov N. N. Ponomarev-Stepnoi V. G. Volkov G. G. Gorodetskii Yu. A. Zverkov O. P. Ivanov S. M. Koltyshev V. D. Muzrukova S. G. Semenov V. E. Stepanov A. V. Chesnokov A. D. Shisha 《Atomic Energy》2007,102(5):375-381
This article is devoted to work done in 2002–2006 as part of the unified project Reabilitatsiya to rehabilitate radiation
hazardous objects and sections of the radioactively contaminated territory of the Russian Science Center Kurchatov Institute.
The main objects of the rehabilitation work were old storage sites built for radioactive wastes on the territory of the Institute
when military and civilian nuclear technologies were under development. The structural features of the storage sites, including
the volumes and characteristics of the wastes stored, are presented. The salient aspects of the disposal sites, taken into
account during the rehabilitation work, are discussed. The organization of the rehabilitation operations and the sequence
in which they are performed, the special features of the technical design solutions used, the technological methods, and ways
for conducting the work are described.
__________
Translated from Atomnaya énergiya, Vol. 102, No. 5, pp. 300–306, May, 2007. 相似文献
997.
N.W. Alnaser R. Flanagan S.E. Al-Khalifa R. Mumtaz S. El-Masri W.E. Alnaser 《Building and Environment》2007
The Bahrain International Circuit (BIC) is considered as one of the best international racing car track in terms of technical aspects and architectural quality. Two Formula 1 races have been hosted in the Kingdom of Bahrain, in 2004 and 2005, at BIC. The BIC had recently won the award of the best international racing car circuit. 相似文献
998.
A. A. Aliev A. V. Suetina A. V. Elistratov A. D. Davydov A. G. Rakhshtadt 《Metal Science and Heat Treatment》2007,49(1-2):75-77
The effect of tempering temperature on the structure, wear resistance, and corrosive properties of steel 08Kh14AN4MDB is studied.
The results of mechanical and corrosion tests are used for constructing an optimization matrix for determining the optimum
tempering temperature.
__________
Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 2, pp. 29–32, February, 2007. 相似文献
999.
M. A. Gasanov 《Surface Engineering and Applied Electrochemistry》2007,43(5):398-402
We present the results of electric discharge treatment of zeolites for purifying the waste water from the manufacture of polymers. By application of the thermostimulated relaxation method, it has been revealed that in the zeolites, superficial and volumetric charges accumulate. It is shown that the electric discharge effects considerably enhance the efficiency of the adsorptive purification of waste water. 相似文献
1000.
A new torque estimator for switched reluctance motor (SRM) drives based on 2-D rotary regression analysis is presented in this paper. The proposed torque estimator is composed of a bicubic regressive polynomial as a function of rotor position and input current. The regressive coefficients can be computed offline or online from the torque characteristics acquired either experimentally or from numerical computation. Furthermore, a torque estimation method by taking mutual coupling into consideration is proposed. It can be seen that the estimated and experimentally obtained self-coupling and mutual-coupling torque characteristics are in good agreement with each other. In addition, the dynamic torque waveforms with and without the mutual coupling, estimated by the proposed estimator, are found to be virtually the same as those obtained from the bicubic spline interpolation for SRM drives with single-pulse voltage, hysteresis current chopping, as well as with voltage pulse width modulation control. The success of all the case studies being reported is a good validation of the usefulness and accuracy of the proposed real-time torque estimator that, as described in this paper, can be used to quickly estimate the instantaneous output torque of SRM drives. 相似文献