机构

• 地理科学与资源研究所 [3]
• 长春光学精密机械与物... [2]

采集方式

• OAI收割 [5]

_filter

_filter

_filter

筛选

浏览/检索结果: 共5条，第1-5条 帮助 条数/页： 5101520253035404550556065707580859095100 排序方式： 请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Spatial sampling design optimization of monitoring network for terrestrial ecosystem in China 期刊论文  OAI收割 SCIENCE OF THE TOTAL ENVIRONMENT, 2022, 卷号: 847, 页码: 12 作者:  Wu Xiaojing;  He Honglin;  Zhang Li;  Feng Lili;  Ren Xiaoli   |  收藏  |  浏览/下载：24/0  |  提交时间：2023/02/27 Forest  Grassland and desert  Spatial representativeness  Spatial sampling method  Data-driven approach   Spatial sampling design optimization of monitoring network for terrestrial ecosystem in China 期刊论文  OAI收割 SCIENCE OF THE TOTAL ENVIRONMENT, 2022, 卷号: 847, 页码: 12 作者:  Wu Xiaojing;  He Honglin;  Zhang Li;  Feng Lili;  Ren Xiaoli   |  收藏  |  浏览/下载：25/0  |  提交时间：2023/02/27 Forest  Grassland and desert  Spatial representativeness  Spatial sampling method  Data-driven approach   Scale-dependence of temporal stability of surface-soil moisture in a desert area in northwestern China SCI/SSCI论文  OAI收割 2015 作者:  Zhang P. P.;  Shao, M. A.;  Zhang, X. C. 收藏  |  浏览/下载：176/0  |  提交时间：2015/12/09 Sampling scales  Re-sampling method  Temporal stability  Soil moisture  Desert ecosystems  remote-sensing footprints  water content  field-scale  spatiotemporal  variability  spatial-patterns  semiarid steppe  time  persistence  validation  hillslopes   Comparison and simulation of subpixel imaging modes for linear CCD (EI CONFERENCE) 会议论文  OAI收割 2012 3rd International Conference on Information Technology for Manufacturing Systems, ITMS 2012, September 8, 2012 - September 9, 2012, Qingdao, China 作者:  Li Y.;  He B.;  Li Y.;  Li Y.;  Li Y. 收藏  |  浏览/下载：38/0  |  提交时间：2013/03/25 Subpixel technique of linear CCD is effective to enhance the spatial resolution without increasing the focal length of optics and reducing the pixel size. To compare image quality of two main subpixel imaging modes  quincunx sampling and four-point sampling  a method to quantitatively evaluate image quality of subpixel based on MTF was proposed. The MTF of quincunx and four-point sampling modes were derived. Analytical results shows that theoretical limiting resolution of quincunx sampling and four-point sampling is improved to 1.4 and 1.86 times respectively  and MTF values at Nyquist frequency of two modes are increased by 0.1106 and 0.1679  respectively. MTFA in (0  0.5) of two subpixel imaging modes were calculated and results illustrates that four-point sampling offers much more improvement with image quality than quincunx sampling  at the cost of double amount of data. A model for simulating subpixel imaging using Matlab was established  and simulation results of spoke target verify the theoretical analysis. (2012) Trans Tech Publications  Switzerland.   Research on the affect of differential-images technique to the resolution of infrared spatial camera (EI CONFERENCE) 会议论文  OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, July 8, 2007 - July 12, 2007, Chengdu, China Jin G.; An Y.; Qi Y.; Hu F. 收藏  |  浏览/下载：18/0  |  提交时间：2013/03/25 The optical system of infrared spatial camera adopts bigger relative aperture and bigger pixel size on focal plane element. These make the system have bulky volume and low resolution. The potential of the optical systems can not be exerted adequately. So  one method for improving resolution of infrared spatial camera based on multi-frame difference-images is introduced in the dissertation. The method uses more than one detectors to acquire several difference images  and then reconstructs a new high-resolution image from these images through the relationship of pixel grey value. The technique of difference-images that uses more than two detectors is researched  and it can improve the resolution 2.5 times in theory. The relationship of pixel grey value between low-resolution difference-images and high-resolution image is found by analyzing the energy of CCD sampling  a general relationship between the enhanced times of the resolution of the detected figure with differential method and the least count of CCD that will be used to detect figure is given. Based on the research of theory  the implementation process of utilizing difference-images technique to improve the resolution of the figure was simulated used Matlab software by taking a personality image as the object  and the software can output the result as an image. The result gotten from the works we have finished proves that the technique is available in high-resolution image reconstruction. The resolution of infrared spatial camera can be improved evidently when holding the size of optical structure or using big size detector by applying for difference image technique. So the technique has a high value in optical remote fields.