A new co-learning method in spatial complex fuzzy inference systems for change detection from satellite images

The detection of spatial and temporal changes (or change detection) in remote sensing images is essential in any decision support system about natural phenomena such as extreme weather conditions, climate change, and floods. In this paper, a new method is proposed to determine the inference process parameters of boundary point, rule coefficient, defuzzification coefficient, and dependency coefficient and present a new FWADAM+ method to train that set of parameters simultaneously. The initial data are clustered simultaneously according to each data group. This result will be the basis for determining a suitable set of parameters by using the FWADAM+ concurrent training algorithm. Eventually, these results will be inherited in the following data groups to build other complex fuzzy rule systems in a shorter time while still ensuring the model’s efficiency. The weather imagery database of the United States Navy (US Navy) is used to evaluate and compare with some related methods using the root-mean-squared error (RMSE), R-squared (R2) measures, and the analysis of variance (ANOVA) model. The experimental results show that the proposed method is up to 30% better than the SeriesNet method, and the processing time is 10% less than that of the SeriesNet method. © 2022, The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature

The effects of Mn concentration on structural and magnetic properties of Ge1-xMnx diluted magnetic semiconductors

Reflexion high-energy electron diffraction (RHEED), transmission electron microscopy (TEM) along with physical property measurement system (PPMS) were used to investigate the growth kinetics of Ge1-xMnx diluted magnetic semiconductors (DMS) grown on Ge(001) by means of molecular beam epitaxy (MBE). At a given intermediate growth temperature of 130 degrees C, we have identified the formation of successive heterogeneous phases when increasing the Mn concentration from 1 to 14 %: DMS phase containing nanosized Mn-rich clusters for x below 2%, DMS phase containing high Curie temperature (T-C) nanocolumns for x ranging from 5 to 6 %, DMS phase in which GeMn nanocolumns and Mn5Ge3 clusters coexist and then finally DMS containing mainly Mn5Ge3 clusters at Mn concentration higher than 12%. Our results confirm that the low solubility of Mn in Ge is the main origin of the formation of heterogeneous phases and provide evidence that it is extremely difficult to form a homogenous GeMn DMS even for Mn concentrations being below 2%. We also demonstrate that high-TC nanocolumns and Mn5Ge3 clusters are competing processes and the process window corresponding to the stabilisation of high-T-C nanocolumns remains extremely tight