A technique for prediction of SPEs from solar radio flux by statistical analysis,ANN and GA     

Kyong Nam Kim  Sun Ae Sin  Kum Ae Song  Jin Hyok Kong 《Astrophysics and Space Science》2018,363(8):170

Solar Radio Flux (SRF) is the significant index in easily evaluating everyday solar activities. From the statistical analysis of SRF at 2800 MHz, 1415 MHz and 610 MHz from 1976 to 1994, and only 111 Solar Proton Events (SPEs) occurring in the same period, we have given the statistical relation between them. In fact, there occurred a total of 131 SPEs in the same period, but we dealt with only 111 SPEs of them, because of lack of SRF data in SGD (2800 MHz, 1415 MHz and 610 MHz). We also discussed the possible parameters of SRF at 2800 MHz, 1415 MHz and 610 MHz for prediction of SPEs by statistical analysis, Artificial Neural Network (ANN) and Genetic Algorithm (GA) using MATLAB. In this study, we used some parameters: the daily total SRF, the overall rate of increase of SRF and SPEs.  相似文献   

Phytoplankton Size and Taxonomic Composition in a Temperate Estuary Influenced by Monsoon     

Yongsik Sin  Bonggil Hyun  Quang-Dung Bach  Sungryull Yang  Chul Park 《Estuaries and Coasts》2012,35(3):839-852

Temporal and spatial variations in phytoplankton in Asan Bay, a temperate estuary under the influence of monsoon, were investigated over an annual cycle (2004). Phytoplankton blooms started in February (>20 μg chl l⁻¹) and continued until April (>13 μg chl l⁻¹) during the dry season, especially in upstream regions. The percentage contribution of large phytoplankton (micro-sized) was high (78–95%) during the blooms, and diatoms such as Skeletonema costatum and Thalassiosira spp. were dominant. The precipitation and freshwater discharge from embankments peaked and supplied nutrients into the bay during the monsoon event, especially in July. Species that favor freshwater, such as Oscillatoria spp. (cyanobacteria), dominated during the monsoon period. The phytoplankton biomass was minimal in this season despite nutrient concentrations that were relatively sufficient (enriched), and this pattern differed from that in tropical estuaries affected by monsoon and in temperate estuaries where phytoplankton respond to nutrient inputs during wet seasons. The flushing time estimated from the salinity was shorter than the doubling time in Asan Bay, which suggests that exports of phytoplankton maximized by high discharge directly from embankments differentiate this bay from other estuaries in temperate and tropical regions. This implies that the change in physical properties, especially in the freshwater discharge rates, has mainly been a regulator of phytoplankton dynamics since the construction of embankments in Asan Bay.  相似文献