In order to reveal the dynamic characteristics of the forest in Bashang area of Hebei Province, MODIS reflectivity and NDVI data with a spatial resolution of 250 m were used for forest classification, and a Thematic Mapper (TM) image in 2005 was resorted to aid training sample selection. With Random Forest Algorithm and time series of MODIS images, the forest in Bashang area was monitored from 2000 to 2015 in every two years. Compared with widely used classifiers such as maximum likelihood classifier and BP artificial neural network algorithm, Random Forest classifier showed the best performance with its overall accuracy and Kappa coefficient being 91.89% and 0.88 respectively. Binary coding was applied to the eight phases of forest distribution images, which can easily and rapidly reflect the changing trajectory from phase to phase. It showed that the severe forest changes mainly occurred in counties of Fengning, Weichang, Zhangbei and Guyuan during the years of 2000, 2010, and 2013.

Basing on the “3D Engineering Investigation Information System”, a “3D Underground Construction Deformation Display System” is developed. Empirical methods were used to predict the deformation of strata and buildings in the system. 3D regular grid model and triangulated irregular network (TIN) model were used for the 3D deformation field visualization. For the TIN model, the adaptive TIN keep-geometry refinement algorithm were developed. This algorithm can depict the deformation field in higher resolution without remarkable data size increase. Therefore the modeling and analysis of very large areas become possible.

The authors report on the current status of the optical frequency standard based on a single ¹¹⁵In⁺ ion. A single Indium ion is trapped in a Paul-Straubel type trap and cooled by sideband cooling to its lowest vibrational states. To interrogate the 5s²¹S₀-5s5p³P₀ clock transition with high accuracy, the authors demonstrate a Hz-level level laser system resonant to this transition. The Absolute frequency measurement is performed with the help of a femtosecond laser referenced to a commercial cesium atomic clock. 20 sessions measurements are achieved. The relative fractional uncertainty is 5.0×10^-14.

The work on fabrication of MgB₂ superconducting thin films via E?Beam evaporation approach is reported. With the Boron film and Mg/B multilayer precursors followed by post?annealing at 900℃ and 750℃ respectively, high quality MgB₂ films have successfully been achieved. Superconducting properties of the samples have been measured and the crystal structure and surface topography have also been characterized. The results showed the performance of these two types of samples was significantly different. Some analyses have been proposed to explain this contrast. Besides, a microwave resonator has been realized based on the superconducting MgB₂ films prepared by this technique.