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101.
102.
Yi Liang Long Zhang Mengdao Xing Zheng Bao 《Frontiers of Electrical and Electronic Engineering in China》2009,4(2):127-133
The frequency modulated continuous wave (FMCW) radar has the characteristics of low probability of interception, good hidden
property and the ability to counter anti-radiation missiles. This paper proposes a new method for high-speed ground moving
target detection (GMTD) using triangular modulation FMCW. According to the characteristic of the opposite range shift induced
by the upslope and downslope modulation FMCW, the upslope and downslope are imaged, respectively. After compensation of continuous
motion of the platform and time difference between upslope and downslope signals for imaging, the moving target can be detected
through displaced phase center antenna (DPCA) technology. When the moving target is detected, the moving target image is extracted,
and correlation processing is used to obtain the range shift, which can be used to estimate the target radial velocity, and
further to find the real position of the target. The effectiveness of this method is verified by the result of computer simulation.
__________
Translated from Journal of Xidian University, 2008, 35(4): 586–591 [译自: 西安电子科技大学学报(自然科学版)] 相似文献
103.
张忠诚 《山东大学学报(工学版)》1990,(2)
设计了一个适用于6个物理化学实验的计算机程序。只需将实验所得的原始数据输入计算机即可得到打印出的原始数据与所求参数的表格和所需要的各类图形。本程序适用于燃烧热、饱和蒸气压、表面张力、反应速度常数的测定以及二元液系相图的绘制。 相似文献
104.
利用Gleeble-3500热模拟试验机研究了低活化马氏体钢在变形温度为850~950 ℃、应变速率为0.001~1 s-1条件下的热变形行为。建立了流变应力本构方程,并评估了该方程的预测能力。绘制了低活化马氏体钢在不同应变下的热加工图。结果表明:在较高的应变速率条件下,该材料主要发生动态回复,在较高变形温度和较低应变速率下具有明显的动态再结晶特征;本构方程的预测结果与实验结果符合良好;变形温度870~930 ℃、应变速率0.001~0.01 s-1和变形温度920~950 ℃、应变速率0.3~1 s-1分别是真应变为0.4和0.6下最优的热加工区域。 相似文献
105.
John A Pritchard 《Computer Communications》1986,9(6):303-316
An outline is given of the information services used in the National Computing Centre. An update is provided of a previous paper describing the local area network implemented in 1981. Three IT landmarks are highlighted, these include the introduction of word processing, the local area network and a digital PABX. The implications and subsequent developments are described. The facilities available on the local area network are discussed. The use of three electronic mail services are also considered, along with the use of facsimile. 相似文献
106.
An improved digital image processing procedure is developed to extract the size and shape of the plastic zone formation at the tip of a notched metal specimen based on the characteristics of the variation of intensity in a digitized image. The result is compared with the result from finite element analysis, and with that from a previously developed image processing procedure. Comparison shows that this method provides a faster and more accurate result than previously. 相似文献
107.
Research on planar-to-stereo image conversion has significant theoretical and practical implications for image processing. In this paper we use a method which segments an image into sub-blocks to perform this kind of conversion; parameters such as random variables are used for conversion control. We use two quantitative criteria, cross-entropy and root-mean-square error, to evaluate the stereo effect. Furthermore, the stereo effect that the random variables create is discussed. The results of the experiment show that, (i) when all random variables have the same distribution, different values of these random variables only slightly affect the stereo effect; and (ii) when different distributions are applied to the random variables, the cross-entropies or root-mean-square errors are slightly different, which indicates different distributions have a small influence on the stereo effect. Generally, we recommend normal distribution for better stereo effect in most cases. 相似文献
108.
109.
110.
This paper proposed two robust scheduling formulations in real manufacturing systems based on the concept of bad scenario set to hedge against processing time uncertainty, which is described by discrete scenarios. Two proposed robust scheduling formulations are applied to an uncertain job-shop scheduling problem with the makespan as the performance criterion. The united-scenario neighbourhood (UN) structure is constructed based on bad scenario set for the scenario job-shop scheduling problem. A tabu search (TS) algorithm with the UN structure is developed to solve the proposed robust scheduling problem. An extensive experiment was conducted. The computational results show that the first robust scheduling formulation could be preferred to the second one for the discussed problem. It is also verified that the obtained robust solutions could hedge against the processing time uncertainty through decreasing the number of bad scenarios and the degree of performance degradation on bad scenarios. Moreover, the computational results demonstrate that the developed TS algorithm is competitive for the proposed robust scheduling formulations. 相似文献