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61.
采用MATLAB图像处理技术在鱼病诊断中的应用 总被引:1,自引:0,他引:1
本文介绍了一种可以对水产养殖中鱼的病变情况进行监控的系统。通过MATLAB软件中强大的图像处理功能,对读入的图像进行中值滤波、灰度处理和二值处理,然后根据收缩与扩张的原理,编写程序,对二值图像进行数次收缩与扩张,以去除杂质点,最后采用区域矩特征的概念,统计出白色像素的数目,与统计数据相比较,即可判断出是否出现鱼类病变死亡等异常情况。 相似文献
62.
宋国安 《武汉工业学院学报》1998,(3)
对我国加速开发植物油脂深加工产品及经济重要性、产品用途、生产工艺等方面作了探讨。介绍了较为成熟的生产工艺,提出了开发生产环氧大豆油、脂肪酸、硬脂酸、甘油、亚油酸、磷脂、糠蜡、植酸钙、肌醇等多种油脂化工产品,创造经济效益的建议。 相似文献
63.
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
64.
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
65.
Optimization of abrasive water jet cutting of ductile materials 总被引:1,自引:0,他引:1
Full factorial design of experiments was developed in order to investigate the effects of jet pressure, abrasive mixing rate, cutting feed, and plate thickness upon three response variables, surface finish of cutting wear zone, percentage proportion of striation free area, and maximum width of cut. The set of sixteen experiments was performed on each of the following two ductile materials: AISI 4340 (high strength low alloy steel, hardened to 49HRc) and Aluminum 2219. Analysis of Variance (ANOVA) was performed on experimental data in order to determine the significance of effects of different parameters on the performance measures. It was found that cutting feed and thickness were highly influential parameters, while abrasive mixing rate is influential upon surface roughness only. Strong interaction was found between jet pressure and workpiece material. Multi-criteria numerical optimization was performed in order to simultaneously maximize/minimize different combinations of performance measures. 相似文献
66.
以仅能获取角度信息的全捷联导引头为研究对象,针对采用直接微分提取惯性视线角速率时存在的噪声放大问题,基于跟踪微分器设计了一种全捷联制导信息提取算法。结合导引头的性能指标要求,对3种不同形式跟踪微分器的提取效果进行了对比分析。仿真结果表明,采用非线性微分器进行惯性视线角速率提取,可以减小延迟时间,避免噪声放大,有效提高制导精度,具有一定的工程应用价值。 相似文献
67.
采用磁控溅射法在n-Ge表面镀镍薄膜,通过改变快速热处理时间研究镍对锗单晶的导电型号、电阻率和少子寿命的影响,以及镍在锗中的扩散行为。结果表明:镍在锗中具有向内扩散和向外扩散两种行为,并以受主状态存在,改变了锗内部的载流子的分布;775℃热处理后,镍受主完全补偿原有的施主,使锗由n型转变为P型,随着热处理时间的增加,电阻率下降,镍受主浓度增加。即使微量的镍就可以使锗的少子寿命直线下降至零点几微秒,这表明镍在锗中会引入深能级。 相似文献
68.
非线性图象处理中有许多操作以逻辑运算为主,并且结构简单、规则、有重复性,非常适于FPGA器件实现。本文以堆栈滤波器为例,研究了利用XC6216器件实现椎栈滤波器的方法以及得到的性能和代价指标。 相似文献
69.
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
70.
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