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Presented here is a new approach to model power electronic components so that system level issues of large space power systems can be studied. To demonstrate this approach, the models for two major power electronic components in the space station power system are described. The new models are useful not only in system level studies but also in the design/analysis of particular components 相似文献
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Chang Tom Tam Sunny W.Y. Wu Cheng-Chin Consolini Giuseppe 《Space Science Reviews》2003,107(1-2):425-445
The first definitive observation that provided convincing evidence indicating certain turbulent space plasma processes are
in states of ‘complexity’ was the discovery of the apparent power-law probability distribution of solar flare intensities.
Recent statistical studies of complexity in space plasmas came from the AE index, UVI auroral imagery, and in-situ measurements
related to the dynamics of the plasma sheet in the Earth's magnetotail and the auroral zone.
In this review, we describe a theory of dynamical ‘complexity’ for space plasma systems far from equilibrium. We demonstrate
that the sporadic and localized interactions of magnetic coherent structures are the origin of ‘complexity’ in space plasmas.
Such interactions generate the anomalous diffusion, transport, acceleration, and evolution of the macroscopic states of the
overall dynamical systems.
Several illustrative examples are considered. These include: the dynamical multi- and cross-scale interactions of the macro-and
kinetic coherent structures in a sheared magnetic field geometry, the preferential acceleration of the bursty bulk flows in
the plasma sheet, and the onset of ‘fluctuation induced nonlinear instabilities’ that can lead to magnetic reconfigurations.
The technique of dynamical renormalization group is introduced and applied to the study of two-dimensional intermittent MHD
fluctuations and an analogous modified forest-fire model exhibiting forced and/or self-organized criticality [FSOC] and other
types of topological phase transitions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Stark L. Tendick F. Kim W. Anderson R. Hisey M. Mills B. Matsunaga K. An Nguyen Ramos C. Tyler M. Zahalak G. Amick M. Baker B. Brown N. Brown T. Chang J. Jyh-Horng Chen Chik J. Cohen D. Cox D. Dubey J. Ellis K. Engdahl E. Frederickson C. Halamka J. Hauser R. Jacobs J. Lee C. Lee D. Liu A. Ninomiya R. Rudolph J. Schafer S. Schendel E. So G. Takeda M. Tam L. Thompson M. Wood E. Woodruff T. 《IEEE transactions on aerospace and electronic systems》1988,24(5):542-551
With major emphasis on simulation, a university laboratory telerobotics facility permits problems to be approached by groups of graduate students. Helmet-mounded displays provide realism; the slaving of the display to the human operator's viewpoint gives a sense of `telepresence' that may be useful for prolonged tasks. Using top-down 3-D model control of distant images allows distant images to be reduced to a few parameters to update the model used for display to the human operator in a preview model to circumvent, in part, the communication delay. Also, the model can be used as a format for supervisory control and permit short-term local autonomous operations. Image processing algorithms can be made simpler and faster without trying to construct sensible images from the bottom. Control studies of telerobots lead to preferential manual control modes and, in this university environment, to basic paradigms for human motion and thence, perhaps, to redesign of robotic control, trajectory path planning, and rehabilitation prosthetics. Speculation as to future industrial drives for this telerobotic field suggests efficient roles for government agencies such as NASA 相似文献
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Kwa-Sur Tam Lifeng Yang Dravid N. 《IEEE transactions on aerospace and electronic systems》1994,30(3):800-808
To facilitate protection system studies on the space station electric power system, there is a need to develop a model that can accurately and conveniently simulate both the power system and the protection system. Models for two major protective devices, the remote bus isolator and the remote power controller, are described. These models have been installed in a power system model resembling one channel of the space station power system. The usefulness of these models in protection system studies Is demonstrated 相似文献
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Recent developments of the physics of complexity in space plasmas are briefly reviewed. The definition of dynamical complexity
is provided. Concepts of probability distribution functions, wavelet transforms, intermittent turbulence, multifractal processes
and extreme events are described. Future directions for this emerging field are discussed. 相似文献
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