Article-Journal

基于小波变换的图像双水印算法

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刘庆亮

Evaluation of Three Temperature Profiles of a Sublayer Scheme to Simulate SST Diurnal Cycle in a Global Ocean General Circulation Model

The diurnal cycle of sea surface temperature (SST) plays an important role in the upper ocean and climate system. One way to represents the diurnal variation of SST in Ocean …

Xiaodan Yang
Spatio-Temporal Variations of Arctic Amplification and Their Linkage with the Arctic Oscillation featured image

Spatio-Temporal Variations of Arctic Amplification and Their Linkage with the Arctic Oscillation

The Arctic near-surface air temperatures are increasing more than twice as fast as the global average–a feature known as Arctic amplification (AA). A modified AA index is …

Yanshuo Wang

论数学建模与创新教育

Chunxia Li
Analytical Solution of the Nitracline with the Evolution of Subsurface Chlorophyll Maximum in Stratified Water Columns featured image

Analytical Solution of the Nitracline with the Evolution of Subsurface Chlorophyll Maximum in Stratified Water Columns

In a stratified water column, the nitracline is a layer where the nitrate concentration increases below the nutrient-depleted upper layer, exhibiting a strong vertical gradient in …

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宫响

一种基于Chebyshev混沌神经网络的视频水印算法

针对视频版权的保护,提出一种基于Chebyshev混沌神经网络的视频水印算法。首先选取二值图像作为图像水印,利用Chebyshev混沌神经网络对图像进行加密;然后对宿主视频进行分帧处理,通过Henon映射产生混沌序列提取关键帧,同时提取关键帧亮度分量的低频系数,将处理后的图像水印自适应地嵌入小波变换后亮度分量的低频系数中。实验结果表明,该算法具有较好的不可见 …

Jiadong Liang

一种图像小波域内分形零水印算法

针对数字图像版权的保护,本文提出了一种小波域内基于分形理论的零水印算法。首先对载体图像进行Haar小波变换,接着对小波低频系数进行分形编码,通过分形匹配获得图像的重要特征信息;然后建立特征信息与图像水印之间的关系,进行水印的双重嵌入;由于算法没有对图像进行任何修改就完成了水印的嵌入,很好地解决水印鲁棒性与不可见性之间的矛盾。仿真实验结果表明,算法对常见的图像 …

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杨树国
Assessing the Impact of Surface and Wind Profiler Data on Fog Forecasting Using WRF 3DVAR: An OSSE Study on a Dense Fog Event over North China featured image

Assessing the Impact of Surface and Wind Profiler Data on Fog Forecasting Using WRF 3DVAR: An OSSE Study on a Dense Fog Event over North China

Because fog is a high-impact weather phenomenon, there has been increased demand for its accurate prediction. Both surface data and wind profiler data possess great potential for …

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胡慧琴
An Effective Method Based on Dynamic Sampling for Data Assimilation in a Global Wave Model featured image

An Effective Method Based on Dynamic Sampling for Data Assimilation in a Global Wave Model

The ensemble Kalman filter (EnKF) performs well because that the covariance of background error is varying along time. It provides a dynamic estimate of background error and …

Meng Sun
Design of Optical-Acoustic Hybrid Underwater Wireless Sensor Network featured image

Design of Optical-Acoustic Hybrid Underwater Wireless Sensor Network

High-speed underwater wireless transmission technologies are urgently demanded to transmit three-dimensional high-resolution observation data timely in ocean exploration. …

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王景景