共查询到20条相似文献，搜索用时 109 毫秒
1.
]?????????????????????????????????????С???任????????????????????????????С???????????????????????????????С???任??????????????????HaarС????db4С????db6С????sym6С?????????С?????????????????????FIR????????????????б??,?????????С??????????????????????????FIR??????????????????????????db???С????????????????????????????????????????????????????????db???С??????????????sym8С???? 相似文献
2.
?????????鳡1994??1996??6??????????????????????????????????????仯????????????????????????????????????????????????仯??????????????????????????仯???????????????7.0??????????????????????????????????????????????????????????仯???????С-?????С-?????С-????-????-??????????????????????????仯????????????-????-??С-?????С-????-???????????????????????????? 相似文献
3.
���ڸĽ���С�������õĵؿǴ�ֱ�α���� 总被引：1，自引：0，他引：1
??????С?????????????????α??????α???????????α????α?????????????????????????????????????С??????????????????????α????????????????????????????α????α??????????????????С???????÷??????????????????????????????α????е???α??????????????С???????÷??????????α????????????????????????????????????????????????????ú????Э?????????????Ч??????????α????α??????????α?????????????????????????GPS?????????????????÷???????????????????????α????α???????????????Ч???????????? 相似文献
4.
?????????????????????С??????????????????????????С????в????????С????в?????????????????????????Σ??о???????С?????????????С??????????С??????????????????????ó???????????????????ó????????? 相似文献
5.
????????С????????????????????ж???????????????????????????????????????????????????????????????????顣?????????????????С??????????????????????3.6??10????-5??ms????-2??????????????С???????????????????????????????????????????????????4.6??10????-5??ms????-2??????????????????????????????????????С?????????????????????????????п???????Ч????? 相似文献
6.
���μ�����ݵ�С��������Ԥ�ⷽ�� 总被引：3，自引：7，他引：3
??????μ?????????????????????????С??????????????????????С???????????????μ??????????????????????????????????ó????????б????ó?????:С??????????????μ??????????????????????Ч???? 相似文献
7.
????????GPS?????????????????????GPS?????????????????????????????????????????????????????????????????????????С??????????巨????λ??????????????ò??????????????????GPS????λ???????????????????????????????????С????????????????????巽???????????????????????λ????????????????Ч??С???????????? 相似文献
8.
???????????????SSA????С??????????????????????????????Ρ???????????????????????????????е?????????С?????????????????????????????????????????????????Ч??????????????????????????????ξ??ж????????????????????X??Y????????????????????????????￡??????????г???? 相似文献
9.
????1999??2001??2001??2004??2004??2007??????ε?GPS????????????????????????????(RELSM)?о???С????????????????ε???????????ó?С???????????????????????3.0~7.1 mm/a????????????????????????Σ????GPS??????棬?о???????????????????????????????????1??С???????????β?????ε???????????η???н?????????????????????????????????????2??RELSM?ó?С???????λ??????????????????????????ε???ε?????????????????С??3??С????????????????????????????θ????б??Σ?????μ???β?????????????????4??С????????????????????????????????????????? 相似文献
10.
С����߶ȷֽ��ڵ���Ԥ���е�Ӧ�� 总被引：1，自引：0，他引：1
??????С?????????????????????1994~1995??2002~2003???2011~2012????????????????仯???з??????1995-07-22????Ms5.8??????2003-10-25????Ms6.1???????2012-05-11????Ms4.9??????????????????о?С???????????????????????á?4??С?????????3?ε???????????????????仯???????????????????????4??С?????????и?????????????????????С??????????ж?????Σ?????? 相似文献
11.
直线拟合边缘检测法在光电自准直仪中的应用 总被引：6，自引：0，他引：6
CCD的分辨率是影响新型光电自准直仪测量精度的关键因素,而边缘检测法是CCD位移测量的主要方法。对数字图像处理中直线拟合边缘检测法进行了详细介绍,并将其应用于高精度一维光电自准直仪的研制。 相似文献
12.
针对数字天顶仪，研究一种解算CCD坐标系x轴与北向之间夹角以实现定向的方法。通过对称位置两幅星图解算得到的天顶仪旋转轴的天文坐标，与已知测站点位置真值进行运算，得到相应的切平面坐标系倾斜量。结合双轴倾角仪测量的倾角计算倾角仪X敏感轴的方位角，并运用最小二乘算法解算出倾角仪的定向角，最终解算出CCD坐标系x轴方位角而实现定向。对数字天顶仪的一个工作循环采集的数据进行解算，得到的方位角标准差σ=3.06′，CCD坐标系x轴方位角满足3σ要求，可以实现定向的目的。 相似文献
13.
线阵CCD数据的高速采集与存储 总被引：14，自引：3，他引：11
在各种高精度线阵CCD应用系统中，需要对像元输出信号进行快速采样、存储及数据处理。CCD数据采集的采样速率不仅与A／D转换器的转换速率等因素有关，同时还与数据传送方式密切相关。以高精度线阵CCD TCD1501D和高速A／D转换器TLC5510为例．详细分析了CCD和A／D转换器的工作时序，采用CPLD设计方法，将CCD的输出信号进行高速A／D转换，并将结果直接存入存储器中。 相似文献
14.
通过CPLD设计间隔精准延迟的驱动脉冲,将线阵CCD空间信息转换为在一个脉冲单元内变化的时间信息,并通过高精度步进电机位移平台进行了检测,实验证明该方法可以有效地突破线阵CCD像元精度限制,实现亚像素测量。 相似文献
15.
航空相机在执行对地观测任务时, 需要精确地调焦控制系统实时调整镜头焦距以获得清晰的图像。本文以航空成像运行模式下的CCD拼接结构的特点,提出了一种智能的航空相机小波调焦方法。将图像处理的清晰度评价方法引入航空相机调焦系统,并考虑人类视觉系统(HVS)的特点设置权值,使评价效果更符合人类的主观感受。本文分析了小波基函数的性质,通过比较得出了采用symlet2小波进行三层分解构造的清晰度评价函数,对不同细节丰富程度的图像具有适应性,得到了灵敏度鲁棒性好的评价函数。并选取细节丰富的区域作为评价函数,详细地介绍了结合航空成像设备CCD拼接结构的特点,进行智能调焦的实现原理及方法。理论分析及仿真试验证实了该算法的可行性及有效性。相比传统评价方法具有较高的灵敏度,小波调焦方法的效率能够满足航空相机实时调焦的需求。 相似文献
16.
WANGYan-li CHENZhe 《中国地理科学(英文版)》2003,13(1):91-96
Several image fusion approaches for CCD/SAR images are studied and the performance evaluation of these fusion approaches is completed in this paper,Fistly,the preprocessing of CCD/SAR images before fusion is fulfilled,Then,the imager fusion methods including linear superposition,nonlinear operator method and multiresolution methods,of which the multiresolution methods include Laplacian pyramid ,ratio pyramied,contrast pyramid,gradient pyramid,morphological pyramid and discrete wavelet transform,are adopted to fuse two types of images ,Lastly,the four performance measures,standard deviation,entropy,cross entropy and spatial frequency,are calculated to compare the fusion results by different fusion approaches in this paper,Experimenteal results show that contrast pyramid,morphology pyramid and discrete wavelet transformation in multiresolution approaches are more suitalbe for CCD/SAR image fusion than other ones proposed in this paper and the objective preformance evaluations of CCD/SAR image fusion approaches are effective. 相似文献
17.
CCD����ˮϵͳ�ı궨��������� 总被引：1，自引：0，他引：1
??????????????????????????CCD?????????????????????????????????????? ????????????:????????????CCD???б?????????????????;????????????崫???????б????????????????????????????????????????????ε?????????????????????????÷??????????????????????????????е??????? 相似文献
18.
BIAN Jin-hu LI Ai-nong JIN Hua-an LEI Guang-bin HUANG Cheng-quan LI Meng-xue 《山地科学学报》2013,10(5):754-767
How to deal with geometric distortion is an open problem when using the massive amount of satellite images at a national or global scale,especially for multi-temporal image analysis.In this paper,an algorithm is proposed to automatically rectify the geometric distortion of time-series CCD multispectral data of small constellation for environmental and disaster mitigation(HJ-1A/B) which was launched by China in 2008.In this algorithm,the area-based matching method was used to automatically search tie points firstly,and then the polynomial function was introduced to correct the systematic errors caused by the satellite motion along the roll,pitch and yaw direction.The improved orthorectification method was finally used to correct pixel displacement caused by off-nadir viewing of topography,which are random errors in the images and cannot be corrected by the polynomial equation.Nine scenes of level 2 HJ CCD images from one path/row were taken as the warp images to test the algorithm.The test result showed that the overall accuracy of the proposed algorithm was within 2 pixels(the average residuals were 37.8 m,and standard deviations were 19.8 m).The accuracies of 45.96% validation points(VPs) were within 1 pixel and 90.33% VPs were within 2 pixels.The discussion showed that three main factors including the distortion patterns of HJ CCD images,percent of cloud cover and the varying altitude of the satellite orbit may affect the search of tie points and the accuracy of results.Although the influence of varying altitude of the satellite orbits is less than the other factors,it is noted that detailed satellite altitude information should be given in the future to get a more precise result.The proposed algorithm should be an efficient tool for the geo-correction of HJ CCD multi-spectral images. 相似文献
19.
Several image fusion approaches for CCD/SAR images are studied and the performance evaluation of these fusion approaches is
completed in this paper. Firstly, the preprocessing of CCD/SAR images before fusion is fulfilled. Then, the image fusion methods
including linear superposition, nonlinear operator method and multiresolution methods, of which the multiresolution methods
include Laplacian pyramid, ratio pyramid, contrast pyramid, gradient pyramid, morphological pyramid and discrete wavelet transform,
are adopted to fuse two types of images. Lastly, the four performance measures, standard deviation, entropy, cross entropy
and spatial frequency, are calculated to compare the fusion results by different fusion approaches in this paper. Experimental
results show that contrast pyramid, morphology pyramid and discrete wavelet transformation in multiresolution approaches are
more suitable for CCD/SAR image fusion than other ones proposed in this paper and the objective performance evalution of CCD/SAR
image fusion approaches are effective.
Foundation item: Under the auspices of Astronautical Innovation Fund of China.
Biography: WANG Yan-li (1977 – ), female, a native of Xi’an City, Shaanxi Province, Ph. D. candidate of School of Automation
Science and Electrical Engineering, Beijing University of Aeronautics and Astronautics, specialized in scene matching, image
registration and fusion. 相似文献
20.
基于模糊控制的快速循迹智能车的设计与实现 总被引：1，自引：0，他引：1
提出基于模糊控制的快速循迹智能车的实现方法.利用转速传感器、线阵CCD、舵机等构成一个闭环控制系统,并采用PI算法控制智能车后轮速度.采用模糊控制算法将线阵CCD返回的误差模糊化,然后按照MAX-MIN规则进行逻辑推理,最后将推理结果反模糊化后以控制舵机转向.实验结果证明了该方法的有效性. 相似文献