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For ergodic SDEs, their ergodic limits are usually approximated by the suitable means of numerical methods. To reveal the numerical asymptotic behavior, we study the large deviations principle (LDP) f...
A new study has presented and characterized the formation and properties of a superparamagnetic ring, which fits snugly around a drop of water due to liquid-liquid interaction, and allows the drops to...
传统K-means聚类算法通过欧式距离计算样本的相似度,将数据所有的属性特征均平等对待,忽略每个属性特征的不同贡献,导致样本相似度计算的准确率不高。针对这个不足,提出一种特征加权的K-means算法进行优化。首先,运用Softmax和Sigmoid逻辑回归函数计算特征权重,使得加权的欧式距离更能准确地表示样本相似度;其次,优化初始聚类中心选择策略,选择距离较大的K个样本作为初始聚类中心,可有效避免...
Coral reefs, seagrass meadows and mangrove forests work together to make the Coral Triangle of Indonesia a hotspot for marine biodiversity. The system supports valuable fisheries and endangered specie...
Locating the boundary parameters of pupil and iris and segmenting the noise free iris portion are the most challenging phases of an automated iris recognition system. In this paper, we have presented ...
3D mesh model segmentation is drawing increasing attentions from digital geometry processing field in recent years. The original 3D mesh model need to be divided into separate meaningful parts or surf...
A research team including a Scripps Institution of Oceanography at the University of California San Diego climate scientist simulated in a computer model, for the first time, the realistic evolution o...
We consider two alternative tests to the Higher Criticism test of Donoho and Jin (2004) for high dimensional means under the spar-sity of the non-zero means for sub-Gaussian distributed data with unkn...
Within the framework of the European MVRRS project (Mitigation of Volcanic Risk by Remote Sensing Techniques), in June 1997 an airborne campaign was organised on Mt. Etna to study different character...
Studies of the dynamics of the ionosphere and its related phenomena are mainly based on Doppler Drift measurements. The time variation (ionisation/recombination) of plasma density, thermospheric wind ...
A preliminary validation of the technique developed using the NeQuick ionospheric model and the 玡ffective ionization parameter?Az, based on vertical total electron content data ingestion, was carried...
In the field of air quality control, optical remote sensing systems can measure the spatial distribution of gas pollutants, offering numerous advantages over conventional networks of in situ analysers...
There are thousands of ways to achieve a sustainable future for our Planet. Some of these follow high-value scientific research activities, while others simply aim to increase people’s awareness of wh...
Efficient Disaster Risk Reduction (DRR) management constantly calls upon high-quality information to be collected or updated for vulnerability monitoring and risk assessment. This process is often res...
Efficient Disaster Risk Reduction (DRR) management constantly calls upon high-quality information to be collected or updated for vulnerability monitoring and risk assessment. This process is often res...

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