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1.
基于扩展分形和CFAR特征融合的SAR图像目标识别 总被引:3,自引:0,他引:3
研究了多信息融合技术在SAR图像目标识别中的应用。将扩展分形特征(Extended Fractal)与双参数恒虚警特征(Double Parameter CFAR)形成的多信息进行融合处理。运用Dempster-Shafer证据理论,在决策层对SAR图像中的像素进行识别分类。实验结果表明通过融合对像素分类的准确性明显好于单特征的检测结果,减少了虚警概率,提高了系统的识别能力。 相似文献
2.
Hong Jeong Jeong‐Ho Park 《International Journal of Adaptive Control and Signal Processing》2002,16(1):1-23
Tracking targets of interest is one of the major research areas in radar surveillance systems. We formulate the problem as incomplete data estimation and apply EM to the MAP estimate. The resulting filter has a recursive structure analogous to the Kalman filter. The advantage is that the measurement‐update deals with multiple measurements in parallel and the parameter‐update estimates the system parameters on the fly. Experiments tracking separate targets in parallel show that tracking maintenance ratio of the proposed system is better than that of NNF and RMS position error is smaller than that of PDAF. Also, the system parameters are correctly obtained even from incorrect initial values. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
3.
L. O. Aizenberg E. A. Khvoles 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(6):379-382
Problems with the construction of transmission lines above a forest are examined. Construction of lines above standing timber
makes it possible to shorten the length of the route, eliminate the clearing of a continuous swath along the line, and reduce
the volume of in-service work. To implement this solution, it is necessary to introduce changes and supplements to existing
regulatory technical documents.
__________
Translated from élektricheskie Stantsii, No. 10, October 2007, pp. 48–51. 相似文献
4.
5.
The syntheses of polyenynes as model compounds for poly(diacetylene)s (PDAs) are described. Variation of properties (UV–VIS, Raman, NMR and bond geometries) as a function of the chain length was investigated. After extrapolation to infinite chain length these data were compared to those for PDAs. From UV–VIS spectra a value of λ = 551 nm (2.25 eV) was calculated corresponding to the electronic transition of a single polyenyne chain. This energy is located at the low energy end of a yellow PDA solution spectrum. From Raman scattering v(C?C) = 2108–2128 cm?1 and v(C?C) = 1505–1532 cm?1 were calculated after extrapolation. Similarly sp-C13C NMR data yielded a shift of δ = 100 ppm. These data are almost identical to data known for yellow PDA solutions. Bond geometries are almost identical to those of poly(diacetylene)s and theoretical data. 相似文献
6.
磁偏转电子枪研制核靶 总被引:3,自引:3,他引:0
文章叙述了磁偏转电子枪的原理和结构以及用EQD-3型电子枪研制各种核靶的工艺过程。 相似文献
7.
随着国内厚板产量的增加,其市场竞争日趋激烈。为了更好的谋求发展,莱钢宽厚板厂在降低生产成本的同时,通过技术改造极大地提高产品的质量。因为板坯成材规格需要精确的长度数据,所以宽厚板板坯长度的精确测量就显得非常重要。本文主要介绍激光测速仪在轧机后测长系统中的应用。 相似文献
8.
The autocorrelation functions and corresponding relaxation times obtained from the forward depolarized quasi-elastic light scattering experiment are exhibited for two quite similar models of flexible polymer chains in solution. A very small change in the chain dynamics is found to be sufficient to change the relaxation time from a relatively short time independent of chain length, with an autocorrelation function suggestive of an unweighted sum of contributions from all the relaxation times in the spectrum of chain motion, to a long time with an autocorrelation function identical with that for the end-to-end vector, strongly dependent upon chain length and dominated by the longest relaxation time in the spectrum. These results raise the question whether widely-used models in which information about short-range chain structure and motion is deliberately omitted can be expected to be appropriate for the interpretation of depolarized scattering experiments. 相似文献
9.
Sam V. Shelton William J. Wepfer Daniel J. Miles 《Chemical Engineering Communications》1988,71(1):39-52
This work deals with the thermal analysis of externally heated porous beds of finite length. A one dimensional model was developed that includes conduction and storage in both the fluid and bed, convective exchange between the fluid and bed, and the effect of adsorption/desorption in the bed. This model results in two coupled differential equations for the fluid and bed temperatures as functions of four independent dimensionless parameters. These equations were solved numerically using finite difference approximations. A truncation error analysis was carried out to maintain an accurate solution. The method of normalization is such that the results of this analysis are of use in bed design when the breakthrough characteristics in finite length beds are of interest. A method to measure bed thermal performance is defined and a means to optimize bed thermal performance is presented. An experiment was conducted to validate the numerically obtained results. A comparison of numerical to experimental results is presented 相似文献
10.
通过对高抗冲聚苯乙烯树脂出现产品落锤指标偏低问题的分析,从橡胶配量及其粒径大小上进行了改进,同时改进了工艺操作,采取了提高反应釜搅拌速度、降低乙苯浓度等措施。结果产品合格率达到99%以上,优级品率达到98%以上。 相似文献