The two objectives of this study are to compare the performances of different data fusion techniques for the enhancement of urban features and subsequently to improve urban land cover types classification using a refined Bayesian classification. For the data fusion, wavelet-based fusion, Brovey transform, Elhers fusion and principal component analysis are used and the results are compared. The refined Bayesian classification uses spatial thresholds defined from local knowledge and different features obtained through a feature derivation process. The result of the refined classification is compared with the results of a standard method and it demonstrates a higher accuracy. Overall, the research indicates that multi-source information can significantly improves the interpretation and classification of land cover types and the refined Bayesian classification is a powerful tool to increase the classification accuracy.

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At present, air pollution has become the main problem in many developed and developing countries. Especially, in Ulaanbaatar city of Mongolia, it has become one of the most tackled issues of every citizen living in the capital city. The aim of this study is to highlight the trend of air pollution and pollution sources in the Mongolian capital and conduct some air pollution analyses. Overall, the study indicates that the air pollution in Ulaanbaatar city is a very serious problem and for its reduction, rapid and thorough measures should be taken.

We present in this paper some results obtained in the field of space geodesy based on continuous GPS observations at the Astronomical Observatory of Mongolia. Starting with a brief historical overview of the main space geodetic activities carried out by the Astronomical Observatory in the past, we outline here current achievements in the application of GPS techniques in the geosciences research in Mongolia. We setup a local GNSS Data Center of the Mongolian Academy of Sciences to receive, quality control and process into derivative products the observation data coming from its continuously recording stations. The quality check performed on three non-real-time permanent stations reveals that all three stations show smooth trends of each parameter indicating good quality in data record and operation without any anomalous behavior.