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Your search keyword '"Zheng, Yong Chun"' showing total 24 results
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24 results on '"Zheng, Yong Chun"'

11. Measurement of the Dielectric Properties of Volcanic Scoria and Basalt at 9370 MHz

Author

Ouyang Ziyuan, Wang Shijie, Zheng Yong-chun, and LI XiongYao

Subjects
Basalt, geography, geography.geographical_feature_category, Volcano, Soil water, Mineralogy, Geology, Dielectric, Scoria, Bulk density, Regolith, Earth (classical element)
Abstract

Dielectric data for volcanic scoria and basalt on the earth at microwave frequency are extremely sparse, and also crucial for volcanic terrains imaging, and development. In consideration of their similarity to lunar regolith (soils and rocks) in chemical and mineral composition, the dielectric data is significative for passive and active microwave remote sensing on the Moon. This study provides the data about the dielectric properties of three kinds of scoria and two kinds of basalt in China. The method put forward in this paper is also applicable for measuring the dielectric properties of dry rocks and other granular ground materials with low complex dielectric constants. Firstly, the authors measured the e' and tanδ values of strip specimens prepared from the mixture of scoria or basalt powder and polythene with the resonant cavity perturbation method at 9370 MHz. Secondly, from the e' and tanδ values of the mixture, the e's and tanδs values of solid scoria and basalt were calculated using Lichtenecker's mixture formulae. Finally, the effective complex dielectric constants, e'e and tanδe, of scoria at different bulk densities were calculated. The results have shown that the e's and tanδs values of all solid basaltic materials measured (both solid basaltic scoria or basalt) are approximately 7 and 0.05, respectively. With increasing bulk density of scoria, the e'e and tanδe values of scoria increase significantly.

Published
2005

24. [Study on GLI values of Polygonatum odoratum base on multi-temporal of unmanned aerial vehicle remote sensing].

Author

Wang Z, Zheng YC, Li JF, Wang YZ, Rong LS, Wang JX, Jiang DC, and Qi WC

Subjects
Chlorophyll A, Plant Leaves, Polygonatum, Remote Sensing Technology
Abstract

Unmanned aerial vehicle(UAV) remote sensing and vegetation index have great potential in the field of Chinese herbal medicine planting. In this study, the visible light image of Polygonatum odoratum planting area in Changyi district of Jilin province were acquired by UAV, and the real-time monitoring of P. odoratum planting area was realized. The green leaf index(GLI) was established, and GLI values of P. odoratum were collected used the spatial sampling points. To compare the GLI values in different periods, it was found that the GLI values of P. odoratum have three stages changing rule of rising-gentle-falling related to the germination, vigorous growth and withered of P. odoratum growth. Meanwhile, the GLI values were compared with four biomass data of P. odoratum, including plant height, leaf area, chlorophyll a and chlorophyll b content in leaves, and it was found that the GLI value was related to the growth potential of P. odoratum. The GLI value with a rapid increase in rising stage or at a high level in the gentle stage means the P. odoratum was in a better growth potential. GLI value has a same change trend with plant height, and has certain correlation with plant height and leaf area. However, there is no obvious relationship between chlorophyll a and chlorophyll b contents in leaves and GLI value. The study clarified the change rule of GLI value of P. odoratum, explained the reason for the change of GLI value, and expanded the application range of GLI. The research shows that UAV and vegetation index can be applied to monitoring the Chinese herbal medicines planting, and provides a new idea for exploring more effective information extraction methods of Chinese herbal medicines.

Published
2020
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