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Liang Y.,Wuhan University of Technology | Tan Z.,Guangxi Meteorological Disaster Mitigation Institute | Luo Y.,Guangxi Polytechnic College
ICCSE 2012 - Proceedings of 2012 7th International Conference on Computer Science and Education | Year: 2012

In order to provide real-time meteorological service and production decision-making guidance for production management department of sugarcane growing area and sugarcane growers, a set of meteorological service system for production management of sugarcane growing area was developed through the integration of the existing expert systems for sugarcane planting and meteorological databases. This paper introduces the system structure design, functional design, database design, and other system design, as well as the application of system. © 2012 IEEE.

Feng Y.,Nanjing Agricultural University | An Z.-C.,CAS Institute of Geology and Geophysics | Sun H.,Guangxi Meteorological Disaster Mitigation Institute | Mao F.,Chinese Academy of Meteorological Sciences
Wuli Xuebao/Acta Physica Sinica | Year: 2010

The fourth generation of comprehensive model of geomagnetic field CM4 is a numerical model in which earth's magnetic field can completely be divided into internal and external parts. In this paper we have calculated and plotted the grid values of internal and external fields of Chinese mainland in every 10 a from 1960 to 2000 by combining CM4 with Taylor polynomial model based on all survey data during 1960-2000, and made more efforts to analyze the whole distribution of crustal anomaly field. Results show that internal field value of northern component X decreased with time. The amplitude was about 750 nT in the period from 1960 to 2000, the trend of external field variation increased in 1960, then gradually decreased about 32 nT until 2000. The internal field value of eastern component Y decreased first, then continuously increased, and its intensities decreased about 40 nT from 1960 to 2000. The trend of external field variation was increased, decreased and increased as time went on, and the external field increased up to about 3.8 nT since 1960. The internal field value of vertical component Z was similar to that of Y, its intensities totally increased about 600 nT. The trend of external field variation decreased and then increased with time, amplitude of which was about 4.6 nT. As for anomalous field, the distributions of components X and Z, total intensity F, and horizontal component H were all negative, the intensities of X and H decreased with longitude while those of Z and F increased. The distributions of Y and declination D were very similar and both of them had positive values in west-central region of China. Their intensities decreased with longitude. The distribution of inclination I was mainly negative, and its intensity increased with longitude. © 2010 Chin. Phys. Soc.

Feng Y.,Nanjing Agricultural University | Pan J.-J.,Nanjing Agricultural University | An Z.-C.,CAS Institute of Geology and Geophysics | Sun H.,Guangxi Meteorological Disaster Mitigation Institute | Mao F.,Chinese Academy of Meteorological Sciences
Chinese Journal of Geophysics (Acta Geophysica Sinica) | Year: 2010

Based on survey data of 156 observatories and repeat stations of China, 6 observatories and 36 IGRF points outside the China in 2000, the geomagnetic field models of total intensity(F), declination(D) and inclination(I) are established by Taylor polynomial model and Surface Spline model, meanwhile, the differential for φ (lotitude) and λ (longitude) of models is carried out to calculate the geomagnetic horizontal gradients, respectively. Then the gradients distribution charts of corresponding components in south-north and east-west direction are drawn, from which a comparison between horizontal gradient charts and IGRF10 for 2000 is made, consistency and difference among these three kinds of horizontal gradient are implemented, too. Finally, the spacial distribution of horizontal gradient is analyzed numerically. Results showed that horizontal gradients of F and I varied mainly with latitude, which of F ranged from 7.0 nT/min to 6.0 nT/min while latitude increased, and got the biggest values in the central region (25°∼35°N, 90°∼120° E) of China, I's gradients varied range from 2'/min to 1'/min while latitude increased, D's gradients varied with both latitude and longitude, which ranged from 0.4'/min to -0. 3'/min in north-south direction while longitude increased and -0.1'/min to -0. 4'/min in east-west direction while latitude increased respectively.

Wang Z.,China Tobacco Guangxi Industrial Co. | Chen Y.,Guangxi Meteorological Disaster Mitigation Institute | Mo J.,Guangxi Meteorological Disaster Mitigation Institute | Wang X.,China Tobacco Guangxi Industrial Co.
Tobacco Science and Technology | Year: 2014

In order to monitor crop planting area and predict its production, HJ-1 satellite (No.1 Environment satellite union of A and B) remote sensing data were used to analyze the spectral reflection characteristics of flue-cured tobacco crop and other ground objects. Three vegetation indices, including normalized difference vegetation index (NDVI), difference vegetation index (DVI) and ratio vegetation index (RVI), were calculated and their discrimination of flue-cured tobacco from other ground objects was analyzed and compared. The method for recognition of flue-cured tobacco from remote sensing data was determined, and the planting information of flue-cured tobacco in Jingxi County, Guangxi was extracted with the developed method. The method precision was verified with GPS field sampling data, and the obtained total precision was 92.79% with Kappa coefficient of 0.8374. It suggested that remote sensing technology could be used to obtain tobacco planting information quickly and accurately.

Feng Y.,Nanjing University of Technology | Sun H.,Guangxi Meteorological Disaster Mitigation Institute | Jiang Y.,Nanjing University of Technology | Mao F.,Chinese Academy of Meteorological Sciences
Acta Seismologica Sinica | Year: 2014

In order to systematically study all non-dipole (ND) magnetic fields (truncation level N=2-10) in China, we studied the spatio-temporal variation of ND magnetic fields with different degree and their energies during the period of 10000 BC-1990 AD based on the newest time-based global model CALS10K.1b. The latest version of IGRF, i.e., IGRF11, was also adopted to compare and verify. Results show that the zero lines of 22, 23 and 24 pole fields mainly moved from middle-northern region to southeastern region of China, from northern to eastern China, and moved from southeastern to northwestern region of China. Except the 26 pole field, all ND fields exhibited “tail raise”. The percentage of ND field accounting for main field oscillated during 10000 BC-1500 AD, and then rapidly increased. The energies of all ND fields changed following almost same trend except the 22 pole field. Around the year 5650 BC, the energy reached high value, and then attenuated with the degree increasing, which indicates that the energy resulting from the Earth core's dynamo attenuates linearly alone with radial distance. The energy of geomagnetic field mainly originates from the Earth's fluid outer core. Comparison of the result based on CALS10K.1b with that from IGRF11 showed that CALS10K.1b's results in this study are more reliable, and their differences mainly result from different data used and modeling methods.

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