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121.
Airborne scatterometers: investigating ocean backscatter under low and high-wind conditions 总被引:1,自引:0,他引:1
Carswell J.R. Carson S.C. McIntosh R.E. Li F.K. Neumann G. McLaughlin D.J. Wilkerson J.C. Black P.G. Nghiem S.V. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1994,82(12):1835-1860
Attempting to understand and predict weather on a local and global basis has challenged both the scientific and engineering communities. One key parameter in understanding the weather is the ocean surface wind vector because of its role in the energy exchange at the air-sea surface. scatterometers, radars that measure the reflectivity of a target offer a tool with which to remotely monitor these winds from tower-, aircraft-, and satellite-based platforms. This paper introduces three current airborne scatterometer systems, and presents data collected by these instruments under low-, moderate-, and high-wind conditions. The paper focuses on airborne scatterometers because of their ability to resolve submesoscale variations in wind fields. Discrepancies between existing theory and the observations are noted and the concerns in measuring low-wind speeds discussed. Finally, the application of using this technology for estimating the surface-wind vector during a hurricane is demonstrated 相似文献
122.
2-D dopant profiling in VLSI devices using dopant-selectiveetching: an atomic force microscopy study
We report a detailed mapping of a 2-D dopant profile on a fully processed industrial sample with large dynamic range and high spatial resolution by utilizing a dopant-selective etching process and Atomic Force Microscopy. The experimental results show excellent agreement with those obtained from SRP and SIMS as corroborative methods. We also discuss the most critical factors which influence the applicability, reproducibility, and reliability of this method 相似文献
123.
Chun Hu Ji Zhao Li G.P. Liu P. Worley E. White J. Kjar R. 《Electron Device Letters, IEEE》1995,16(2):61-63
The effects of the plasma etching process induced gate oxide damages on device's low frequency noise behavior are investigated on MOSFET's fabricated with different field plate perimeter to gate area ratio antennas. Abnormal 1/f noise spectrum with a shoulder centered in the frequency range of 100 and to 1 kHz was frequently observed in small geometry devices, and it is attributable to a nonuniform distribution of oxide traps induced by plasma etching process 相似文献
124.
格状编码和RS码级连技术在HDTV中应用的性能模拟 总被引:1,自引:0,他引:1
设计一种用于HDTV地面数字传输系统的级连格状编码和RS码方案,并对其在HDTV中应用进行计算机模拟。模拟结果表明:该级连格状编码方案在低信噪比具有较好的误码性能。 相似文献
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Li W. Aiken M. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》1998,28(2):288-294
Many real-world decision-making problems fall into the general category of classification. Algorithms for constructing knowledge by inductive inference from example have been widely used for some decades. Although these learning algorithms frequently address the same problem of learning from preclassified examples and much previous work in inductive learning has focused on the algorithms' predictive accuracy, little attention has been paid to the effect of data factors on the performance of a learning system. An experiment was conducted using five learning algorithms on two data sets to investigate how the change in labeling the class attribute can alter the behavior of learning algorithms. The results show that different preclassification rules applied on the training examples can affect either the classification accuracy or classification structure 相似文献
128.
受中国电信委托、原邮电部经济技术发展研究中心在全国进行一次农村电信市场调查,以了解当前农村通信市场发展潜力,本文公布了此次调查的结果,从经济能力、资费和潜在市场等方面提出了发展农话的建议 。 相似文献
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厚膜导体Pd-Ag/Au、Pt-Pd-Au/Au平面复合结构,Pd-Ag/Au立体复合结构可使多种组装技术相互兼容。立体复合结构还可有效地降低导体线电阻,减少线损耗。而且,其超声键合性尤佳 相似文献