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排序方式: 共有2297条查询结果,搜索用时 31 毫秒
991.
992.
In this article a problem of relation between p-adic and ordinary quantum mechanics is discussed.
The text was submitted by the author in English. 相似文献
993.
Based on entanglement swapping, a scheme for the secret sharing of an arbitrary
two-particle entangled state is proposed. If the controllers do not co-operate
with the eavesdropper, the eavesdropper's successful probability decreases with the
number of the controllers increasing.
In addition,
only the Bell-state measurements are
required to realize the secret sharing scheme. 相似文献
994.
Joachim Werther Ernst-Ulrich Hartge Lars Ratschow Reiner Wischnewski 《Particuology》2009,7(4):324-331
The concept of simulation-supported measurement is suggested for the elucidation of processes occurring in the combustion chambers of large-scale circulating fluidized bed combustors where the desired information cannot be obtained by direct measurements. The concept is illustrated with the example of secondary air injection where the way the air is released, the penetration depth and the evenness of air distribution over the cross-sectional area of the combustion chamber are of interest. The measured information consists of lateral profiles of oxygen concentrations measured with gas sampling probes at two ports which were located 5 and 9 m, respectively, above the level of secondary air injection. The simulation is carried out on the basis of a 3D semi-empirical fluid-mechanical model of the circulating fluidized bed which is combined with models of gas and solids mixing, fuel distribution, devolatilization and combustion of char and volatiles. The combination of the simulation with the measurements yields a clear picture of the mechanism of secondary air injection, its penetration into the combustion chamber and its effect on the local combustion processes. The results confirm the usefulness of the concept of simulation-supported measurement for this application. 相似文献
995.
Controlling chaos in permanent magnet synchronous motor based on finite-time stability theory
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This paper reports that the performance of permanent magnet
synchronous motor (PMSM) degrades due to chaos when its systemic
parameters fall into a certain area. To control the undesirable
chaos in PMSM, a nonlinear controller, which is simple and easy to
be constructed, is presented to achieve finite-time chaos control
based on the finite-time stability theory. Computer simulation
results show that the proposed controller is very effective. The
obtained results may help to maintain the industrial servo driven
system's security operation. 相似文献
996.
997.
998.
Approximate Real–Time Visualization of a Quantum Transition by Means of Continuous Fuzzy Measurement
Jürgen Audretsch Thomas Konrad Michael Mensky 《General Relativity and Gravitation》2001,33(7):1165-1180
For the detection of gravitational waves the quantum mechanical properties of the detector have to be taken into account. Not all gravitational wave detectors allow a quantum nondemolition (QND) measurement. Continuous weak or fuzzy measurements are an alternative to study the evolution of a quantum mechanical system under the influence of an external field. In the present paper we investigate this alternative by applying it to a simplified system. We numerically simulate continuous fuzzy measurements of the oscillations of a two-level atom subjected to a resonant external light field. We thereby address the question whether it is possible to measure characteristic features of the evolution of a single quantum system in real time without relying on a QND scheme. We compare two schemes of continuous measurement: continuous measurement with constant fuzziness and with fuzziness changing in the course of the measurement. Because the sensitivity of the two-level atom to the influence of the measurement depends on the state of the atom, it is possible to optimize the continuous fuzzy measurement by varying its fuzziness. 相似文献
999.
本文介绍了新研制成功的用于对大力值(最大1200KN)、宽频带(最高分析频率50kHz)的力传感器动态特性校准的标准负阶跃力装置,该装置是基于帕斯卡原理和冲击卸荷方法来实现的,文中详细介绍了力传感器输出电压和用激光测速仪测量负阶跃力跃变过程的高速数据同步采集技术。 相似文献
1000.
M. Weiszflog G. de Angelis A. Axelsson D. Bazzacco F. Becker M. De Poli J. Eberth C. Fahlander A. Gadea S. Lunardi D.R. Napoli J. Nyberg C. Rossi Alvarez B. Rubio D. Rudolph S. Skoda H.G. Thomas R. Wyss 《The European Physical Journal A - Hadrons and Nuclei》2001,11(1):25-38
High-spin states in the nuclei 63Ga and 65Ga were studied following the reaction 32S + 40Ca at a reaction energy of 125 MeV and using the GASP γ-ray spectrometer in combination with the ISIS charged-particle detector
system. In addition to low-lying negative-parity states with single-particle character, rotational-like cascades built on
the 9/2+ and 19/2- states have been observed in both nuclei. Sidebands with negative parity in 63Ga and positive parity in 65Ga could be established. The experimental results are compared with Total Routhian Surface calculations which describe the
nuclei as moderately deformed (β2≈ 0.25) and γ soft at low rotational frequencies. The highest experimentally observed positive-parity state in 65Ga (41/2+) is in good agreement with the calculated crossing of the collective band with a non-collective one terminating at this spin.
Received: 20 December 2000 / Accepted: 2 May 2001 相似文献