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11.
文中主要介绍了一种基于FPGA的将高速并行遥测数据(BMK)转为RS422传输协议进行长线传输的设计。在半实物仿真浸4试中,要求数据采集系统能够实时且准确的采集数据。将BMK转化为RS422协议传输后可以在保证其精度与速度的同时能够大大延长其传输距离。实际应用表明,此设计具有简捷经济、测试准确的特点,具有很好的实用价值。 相似文献
12.
采用多台开关电源并联运行实现大功率电源系统输出是目前电源技术的发展方向之一。文中阐述了传统的并联均流电路,并提出了一种新型的并联均流方式,采用此并联均流方式,完成了48 V400 A高功率电源的实验。实验结果表明,并联均流效果理想,可满足高功率电源的设计要求。 相似文献
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In this paper we study the families of ETOL and EOL array languages. Standard forms for ETOL and EOL array systems are defined
and closure properties of the families are studied. Relations of these families with other developmental array languages and
other array languages are studied. 相似文献
17.
A chaotic synchronized system of two coupled skew tent maps is discussed in this paper. The locally and globally riddled basins of the chaotic synchronized attractor are studied. It is found that there is a novel phenomenon in the local-global riddling bifurcation of the attractive basin of the chaotic synchronized attractor in some specific coupling intervals. The coupling parameter corresponding to the locally riddled basin has a single value which is embedded in the coupling parameter interval corresponding to the globally riddled basin, just like a breakpoint. Also, there is no relation between this phenomenon and the form of the chaotic synchronized attractor. This phenomenon is found analytically. We also try to explain it in a physical sense. It may be that the chaotic synchronized attractor is in the critical state, as it is infinitely close to the boundary of its attractive basin. We conjecture that this isolated critical value phenomenon will be common in a system with a chaotic attractor in the critical state, in spite of the system being discrete or differential. 相似文献
18.
G. Alberti G. Bellettini M. Cassandro E. Presutti 《Journal of statistical physics》1996,82(3-4):743-796
We consider an Ising spin system with Kac potentials in a torus of d,d>-2, and fix the temperature below its Lebowitz-Penrose critical value. We prove that when the Kac scaling parameter vanishes, the log of the probability of an interface becomes proportional to its area and the surface tension, related to the proportionality constant, converges to the van der Waals surface tension. The results are based on the analysis of the rate functionals for Gibbsian large deviations and on the proof that they -converge to the perimeter functional of geometric measure theory (which extends the notion of area). Our considerations include nonsmooth interfaces, proving that the Gibbsian probability of an interface depends only on its area and not on its regularity. 相似文献
19.
In this paper, the characteristics of synchronized traffic in mixed traffic flow are investigated based on the braking light model. By introducing the energy dissipation and the distribution of slowdown vehicles, the effects of the maximum velocity, the mixing ratio, and the length of vehicles on the synchronized flow are discussed. It is found that the maximum velocity plays a great role in the synchronized flow in mixed traffic. The energy dissipation and the distribution of slowdown vehicles in the synchronized flow region are greatly different from those in free flow and a traffic jamming region. When all of vehicles have the same maximum velocity with V max > 15, the mixed traffic significantly displays synchronized flow, which has been demonstrated by the relation between flow rate and occupancy and estimation of the cross-correlation function. Moreover, the energy dissipation in the synchronized flow region does not increase with occupancy. The distribution of slowdown vehicles shows a changeless platform in the synchronized flow region. This is an interesting phenomenon. It helps to deeply understand the synchronized flow and greatly reduce the energy dissipation of traffic flow. 相似文献
20.
Synchronized whistlers recorded at Varanasi 总被引:1,自引:0,他引:1
Some interesting events of synchronized whistlers recorded at low latitude station Varanasi during magnetic storm period of
the year 1977 are presented. The dynamic spectrum analysis shows that the component whistlers are Eckersley whistlers having
dispersion 10 s1/2 and 30 s1/2. An attempt has been made to explain the dynamic spectra using lightning discharge generated from magnetospheric sources 相似文献