机构

• 数学与系统科学研究院 [3]
• 长春光学精密机械与物... [1]

采集方式

• OAI收割 [4]

内容类型

• 期刊论文 [3]
• 会议论文 [1]

发表日期

• 2019 [1]
• 2011 [2]
• 2006 [1]

学科主题

筛选

浏览/检索结果: 共4条，第1-4条 帮助 条数/页： 5101520253035404550556065707580859095100 排序方式： 请选择题名升序题名降序提交时间升序提交时间降序作者升序作者降序发表日期升序发表日期降序 Apparent singularities of D-finite systems 期刊论文  OAI收割 JOURNAL OF SYMBOLIC COMPUTATION, 2019, 卷号: 95, 页码: 217-237 作者:  Chen, Shaoshi;  Kauers, Manuel;  Li, Ziming;  Zhang, Yi   |  收藏  |  浏览/下载：31/0  |  提交时间：2020/01/10 D-finite system  Grobner basis  Ordinary point  Formal power series  Apparent singularity  Desingularization   Positive solutions for a multi-parameter system of second-order ordinary differential equations 期刊论文  OAI收割 SCIENCE CHINA-MATHEMATICS, 2011, 卷号: 54, 期号: 5, 页码: 959-972 作者:  Cheng XiYou;  Zhang ZhiTao   |  收藏  |  浏览/下载：14/0  |  提交时间：2018/07/30 positive solution  ordinary differential systems  fixed point index   A hybrid median filter for enhancing dim small point targets and its fast implementation (EI CONFERENCE) 会议论文  OAI收割 2011 International Conference on Multimedia and Signal Processing, CMSP 2011, May 14, 2011 - May 15, 2011, Guilin, Guangxi, China Yang Q. 收藏  |  浏览/下载：20/0  |  提交时间：2013/03/25 Weak stars and middle altitude orbit satellites or high altitude orbit satellites are presented as dim point targets in images of astronomical observation. They have low intensity and occupy few pixels in image. In most situations  the background of sky is always ununiform and there exists pulse noises. Thus results in targets submerging in background noises and low signal noise ratio (SNR). Median filter is an effective method for removing pulse noise. But it can blur image after modifying gray of non-noise pixels when image has low SNR. A hybrid median filter algorithm is proposed to process low SNR dim point targets image. The newly proposed method can suppress the pulse noises  also can increase target $SNR$ and does not add extra fake targets. The time complexity of median filter is O(N2)(N is the widow size) and is difficult to implement in hardware. For quasi real time application  a fast implementation of our hybrid median filter is proposed to reduce the time complexity to O(N). Experimental results show that the newly proposed algorithm is superior to ordinary median filter and fast median filter by comparing visual effect and performance. 2011 IEEE.   Upper and lower solution method for fourth-order four-point boundary value problems 期刊论文  OAI收割 JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS, 2006, 卷号: 196, 期号: 2, 页码: 387-393 作者:  Zhang, Qin;  Chen, Shihua;  Lu, Jinhu   |  收藏  |  浏览/下载：17/0  |  提交时间：2018/07/30 lower and upper solution method  fourth-order ordinary differential equation  four-point boundary conditions