中国科学院机构知识库网格系统: 检索

The thresholds of forest-to-grassland ratios can be critical for harmonizing ecosystem service relationships spatiotemporally in dryland regions 期刊论文 OAI收割
APPLIED GEOGRAPHY, 2024, 卷号: 169, 页码: 8
作者: Luo, Ying; Lu, Yihe; Guo, Xingjian; Liu, Yuanxin; Zhang, Liwei

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收藏 | 浏览/下载：5/0 | 提交时间：2024/12/30

Ecosystem services Scale effect Threshold identification Ecological restoration Drylands

An evaluation of automated GPD threshold selection methods for hydrological extremes across different scales 期刊论文 OAI收割
JOURNAL OF HYDROLOGY, 2020, 卷号: 585, 页码: 15
作者: Curceac, Stelian; Atkinson, Peter M.; Milne, Alice; Wu, Lianhai; Harris, Paul

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收藏 | 浏览/下载：40/0 | 提交时间：2021/07/09

Generalized pareto distribution Peaks over threshold Threshold selection Flood frequency analysis Scale effects Grassland agriculture

Soil properties and distribution in the riparian zone: the effects of fluctuations in water and anthropogenic disturbances 期刊论文 OAI收割
EUROPEAN JOURNAL OF SOIL SCIENCE, 2019, 卷号: 70, 期号: 3, 页码: 664-673
作者: Ye, Fei; Ma, Mao H.; Wu, Sheng J.; Jiang, Yi; Zhu, Gui B.

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收藏 | 浏览/下载：64/0 | 提交时间：2019/06/24

local-scale factor multivariate regression tree regional-scale factor riparian soil threshold system

A new image denoising method based on wavelet multi-scale registration fusion 会议论文 OAI收割
Shenzhen, China, July 13-15, 2018
作者: Ma Y(马钺); Gao L(高亮); Wu, Jing Hui; Chen S(陈帅); Wu JH(吴景辉)

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收藏 | 浏览/下载：29/0 | 提交时间：2019/03/09

image denoising wavelet transform wavelet multi-scale registration fusion improved wavelet threshold shrink

Water use efficiency threshold for terrestrial ecosystem carbon sequestration in China under afforestation SCI/SSCI论文 OAI收割
2014
作者: Gao Y.; Tian J.

收藏 | 浏览/下载：36/0 | 提交时间：2014/12/24

Water use efficiency C sequestration Afforestation Precipitation isoline Threshold value Climatic zone forest ecosystems semiarid areas eastern china nitrogen scale productivity environment limitation responses patterns

Improved continuous wavelet analysis of variation in the dominant period of hydrological time series SCI/SSCI论文 OAI收割
2013
作者: Wang D.

收藏 | 浏览/下载：15/0 | 提交时间：2014/12/24

hydrological series analysis continuous wavelet transform wavelet basis function multi-temporal scale wavelet spectrum period trend change points maximum entropy spectral analysis de-noising entropy spectral-analysis decomposition identification transform threshold model

Multi-focus image fusion algorithm based on adaptive PCNN and wavelet transform (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Wu Z.-G.; Wang M.-J.; Han G.-L.

收藏 | 浏览/下载：78/0 | 提交时间：2013/03/25

Being an efficient method of information fusion image fusion has been used in many fields such as machine vision medical diagnosis military applications and remote sensing.In this paper Pulse Coupled Neural Network (PCNN) is introduced in this research field for its interesting properties in image processing including segmentation target recognition et al. and a novel algorithm based on PCNN and Wavelet Transform for Multi-focus image fusion is proposed. First the two original images are decomposed by wavelet transform. Then based on the PCNN a fusion rule in the Wavelet domain is given. This algorithm uses the wavelet coefficient in each frequency domain as the linking strength so that its value can be chosen adaptively. Wavelet coefficients map to the range of image gray-scale. The output threshold function attenuates to minimum gray over time. Then all pixels of image get the ignition. So the output of PCNN in each iteration time is ignition wavelet coefficients of threshold strength in different time. At this moment the sequences of ignition of wavelet coefficients represent ignition timing of each neuron. The ignition timing of PCNN in each neuron is mapped to corresponding image gray-scale range which is a picture of ignition timing mapping. Then it can judge the targets in the neuron are obvious features or not obvious. The fusion coefficients are decided by the compare-selection operator with the firing time gradient maps and the fusion image is reconstructed by wavelet inverse transform. Furthermore by this algorithm the threshold adjusting constant is estimated by appointed iteration number. Furthermore In order to sufficient reflect order of the firing time the threshold adjusting constant is estimated by appointed iteration number. So after the iteration achieved each of the wavelet coefficient is activated. In order to verify the effectiveness of proposed rules the experiments upon Multi-focus image are done. Moreover comparative results of evaluating fusion quality are listed. The experimental results show that the method can effectively enhance the edge details and improve the spatial resolution of the image. 2011 SPIE.

An adaptive edge detection method based on Canny operator (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Civil Engineering and Building Materials, CEBM 2011, July 29, 2011 - July 31, 2011, Kunming, China
作者: Chen Y.

收藏 | 浏览/下载：41/0 | 提交时间：2013/03/25

This paper proposes an adaptive Canny operator edge detection algorithm. The proposed method can automatically set the threshold value according to the different image gray-scale gradient histogram adaptively and improve the performance in the detail edge detection and good localization. Experiments show that this method produces better edge detection results performance than the Otsu method. Besides our method Roberts operator Prewitt operator Sobel operator Log operator and Canny operator based on Otsu algorithm are also tested for comparisons. (2011) Trans Tech Publications Switzerland.

The application of wavelet transformation in pulsar signal denoising 会议论文 OAI收割
2011 International Conference on Transportation, Mechanical, and Electrical Engineering, Changchun, China, December 16-18,2011
作者: Yong Chen; Zhengwen Sun; Liangquan Jia; Sixiu Wang

收藏 | 浏览/下载：18/0 | 提交时间：2014/12/12

Wavelet Transform Denoising Pulsar Decomposition scale Threshold

Predicting the potential distribution of the endangered przewalski's gazelle 期刊论文 iSwitch采集
Journal of zoology, 2010, 卷号: 282, 期号: 1, 页码: 54-63
作者: Hu, J.; Jiang, Z.

收藏 | 浏览/下载：29/0 | 提交时间：2019/05/10

Maxent Procapra przewalskii Scale effect Species distribution modelling Competing suitability models Threshold-determining approach