ISSN 1000-0526
CN 11-2282/P
CN 11-2282/P
Volume 26,Issue 12,2000 Table of Contents
2000, 26(12):3-7.
DOI: 10.7519/j.issn.1000-0526.2000.12.001
Abstract:
The programming algorithm of the F distribution functions was described.The new statistical verification method introduced not only advoids the trivial table look up but also overcomes the inaccuracy by changing the degree of freedom randomly in the automatical analysis for the traditional verification method.So the regression equations developed by screening predictors accurately and the statistical verification can be automatized.The traditional statistical verification method is improved by this new statistical verification method which is adoptive for meteorological stations in China.
The programming algorithm of the F distribution functions was described.The new statistical verification method introduced not only advoids the trivial table look up but also overcomes the inaccuracy by changing the degree of freedom randomly in the automatical analysis for the traditional verification method.So the regression equations developed by screening predictors accurately and the statistical verification can be automatized.The traditional statistical verification method is improved by this new statistical verification method which is adoptive for meteorological stations in China.
2000, 26(12):8-11.
DOI: 10.7519/j.issn.1000-0526.2000.12.002
Abstract:
The positive action of tombarthite to improve corn stress-resistance under the low temperature situation was discussed according to physiological aspect through experiments. The experimental result shows that the tombarthite could increase the content of resolvable sugar,decrease electric conductivity,increase chlorophyll content,raise photosynthesis rate and increase corn grain yield under low temperature condition.
The positive action of tombarthite to improve corn stress-resistance under the low temperature situation was discussed according to physiological aspect through experiments. The experimental result shows that the tombarthite could increase the content of resolvable sugar,decrease electric conductivity,increase chlorophyll content,raise photosynthesis rate and increase corn grain yield under low temperature condition.
2000, 26(12):12-15.
DOI: 10.7519/j.issn.1000-0526.2000.12.003
Abstract:
By dint of optimum correlation method the predictors,which are good indicators of winter wheat scab occurrence in Taihu area in Jiangsu province,were input into the feed forward multi-layer artificial neural network(ANN) based on back-propagation study.ANN prediction model for occurrence of winter wheat scab was developed.The influence of model parameters on the fitting and prediction accuracy of model was studied.It can be concluded that total error square sum(E) has the most outstanding impact on model function than other parameters.The smaller is the value of E,the higher is fitting accuracy for historical samples.Extreme small E will result in lower prediction accuracy for independent samples.The action of number of neurons in the hidden layer (Nh),study factor( α) and momentum factor (β) may be ignored when suitable E was given to make model stable.
By dint of optimum correlation method the predictors,which are good indicators of winter wheat scab occurrence in Taihu area in Jiangsu province,were input into the feed forward multi-layer artificial neural network(ANN) based on back-propagation study.ANN prediction model for occurrence of winter wheat scab was developed.The influence of model parameters on the fitting and prediction accuracy of model was studied.It can be concluded that total error square sum(E) has the most outstanding impact on model function than other parameters.The smaller is the value of E,the higher is fitting accuracy for historical samples.Extreme small E will result in lower prediction accuracy for independent samples.The action of number of neurons in the hidden layer (Nh),study factor( α) and momentum factor (β) may be ignored when suitable E was given to make model stable.
2000, 26(12):16-19.
DOI: 10.7519/j.issn.1000-0526.2000.12.004
Abstract:
The Barnus band-pass filtering method was applied to analyze two high wind and hail events,which occur in spring over the southern Yunnan.The results show that there are mesoscale waves within the lower atmosphere near Kunming Quasi-stationary Front before the convective weather happens.The area of high wind and hail includes a sinking motion center and a ascending motion center.
The Barnus band-pass filtering method was applied to analyze two high wind and hail events,which occur in spring over the southern Yunnan.The results show that there are mesoscale waves within the lower atmosphere near Kunming Quasi-stationary Front before the convective weather happens.The area of high wind and hail includes a sinking motion center and a ascending motion center.
2000, 26(12):20-23.
DOI: 10.7519/j.issn.1000-0526.2000.12.005
Abstract:
Based on fall-winter depth of snow and days of snow lying at 17 stations in the eastern part of the Tibetan Plateau from 1957 to 1988,the different distribution characteristics of the average geopotential height at 500hPa level in summer were respectively analyzed when the depth of snow and days of snow lying were anomalous.The distribution characteristics of the average geopotential height at 500hPa level when the tropical cyclones affected Fujian more or less was compared.The two distribution characteristics were similar.The result indicates that the frequency of tropical cyclones affecting Fujian will be increased(decreased)when the fall winter depth of snow is more(less),when the fall winter days of snow lying is more,the frequency of tropical cyclones will be decreased.
Based on fall-winter depth of snow and days of snow lying at 17 stations in the eastern part of the Tibetan Plateau from 1957 to 1988,the different distribution characteristics of the average geopotential height at 500hPa level in summer were respectively analyzed when the depth of snow and days of snow lying were anomalous.The distribution characteristics of the average geopotential height at 500hPa level when the tropical cyclones affected Fujian more or less was compared.The two distribution characteristics were similar.The result indicates that the frequency of tropical cyclones affecting Fujian will be increased(decreased)when the fall winter depth of snow is more(less),when the fall winter days of snow lying is more,the frequency of tropical cyclones will be decreased.
2000, 26(12):24-28.
DOI: 10.7519/j.issn.1000-0526.2000.12.006
Abstract:
The climatic features of heavy snow,snowstorm and snow disaster happened in Inner Mongolia were analyzed by using of the historical data of 131 meteorological observing stations in Inner Mongolia and the aerological 500hPa data in Asian-European region from 1961 to 1988.The analyses show that most of the heavy snow,snowstorm usually occurred in the east and north of Inner Mongolia,but the most severe snow disaster took place in the north of the area,and Zuodongxue(keeping snows cover in whole winter) is essential condition of snow disasters,and the meteorological parameters forming Zuodongxue were determined.The circulation features of heavy snow,snowstorm and snow disaster in Inner Mongolia were summarized.
The climatic features of heavy snow,snowstorm and snow disaster happened in Inner Mongolia were analyzed by using of the historical data of 131 meteorological observing stations in Inner Mongolia and the aerological 500hPa data in Asian-European region from 1961 to 1988.The analyses show that most of the heavy snow,snowstorm usually occurred in the east and north of Inner Mongolia,but the most severe snow disaster took place in the north of the area,and Zuodongxue(keeping snows cover in whole winter) is essential condition of snow disasters,and the meteorological parameters forming Zuodongxue were determined.The circulation features of heavy snow,snowstorm and snow disaster in Inner Mongolia were summarized.
2000, 26(12):29-30.
DOI: 10.7519/j.issn.1000-0526.2000.12.007
Abstract:
Based on the data of monthly mean wind vector field in the stratosphere,an analysis of variation characteristics of quasi-biennial oscillation (QBO) of longitudinal wind was made. It is revealed the relationship between QBO fluctuation and climatic variation in Guangxi province.
Based on the data of monthly mean wind vector field in the stratosphere,an analysis of variation characteristics of quasi-biennial oscillation (QBO) of longitudinal wind was made. It is revealed the relationship between QBO fluctuation and climatic variation in Guangxi province.
2000, 26(12):31-35.
DOI: 10.7519/j.issn.1000-0526.2000.12.008
Abstract:
Several viewpoints for the forecasting of typhoon forming were gained according to analysis of some observed phenomena of the relationship between typhoon and the location and intensity of the northern polar vortex,the intensity index of East Asian westerly and the evolution of the southern hemisphere large-scale circulation.
Several viewpoints for the forecasting of typhoon forming were gained according to analysis of some observed phenomena of the relationship between typhoon and the location and intensity of the northern polar vortex,the intensity index of East Asian westerly and the evolution of the southern hemisphere large-scale circulation.
2000, 26(12):36-37.
DOI: 10.7519/j.issn.1000-0526.2000.12.009
Abstract:
MICAPS satellitic nephogram file lacks generality.Three methods of processing satellitic nephogram were introduced.The first method is to call MICAPS program by ″shell″ function.The second method is to capture picture by clipboard.The last method is to transfer the data format of satellitic nephogram file into BMP picture.
MICAPS satellitic nephogram file lacks generality.Three methods of processing satellitic nephogram were introduced.The first method is to call MICAPS program by ″shell″ function.The second method is to capture picture by clipboard.The last method is to transfer the data format of satellitic nephogram file into BMP picture.
2000, 26(12):38-42.
DOI: 10.7519/j.issn.1000-0526.2000.12.010
Abstract:
Ultraviolet Index (UVI)is 0—15,a unitless value.At night,UVI is 0.On tropical plateau,UVI is 15 on clear sky.The WMO standard UV index unit is equal to 25mW/m2 erythemally weighted dose rate.The major methods of forecast of surface sunny Ultraviolet Index consist of statistics forecast and model forecast.The statistics forecast mainly depends on the observed UVI and cloud amount data,and the model forecast mainly depends on forecasting the ozone field and applied radiative transfer model.
Ultraviolet Index (UVI)is 0—15,a unitless value.At night,UVI is 0.On tropical plateau,UVI is 15 on clear sky.The WMO standard UV index unit is equal to 25mW/m2 erythemally weighted dose rate.The major methods of forecast of surface sunny Ultraviolet Index consist of statistics forecast and model forecast.The statistics forecast mainly depends on the observed UVI and cloud amount data,and the model forecast mainly depends on forecasting the ozone field and applied radiative transfer model.
2000, 26(12):43-46.
DOI: 10.7519/j.issn.1000-0526.2000.12.011
Abstract:
The relationship of fire and weather factors was analysed by using of meteorological data and 1443 fire events at Zhenjiang city of Jiangsu province in seven years.Fire weather type was divided and fire weather index was given.Then,the stepwise regression equation of index forecast of fire weather at Zhenjiang was established by using of T106 products.The forecast accuracy of the operational experiment in two months is 83.6%.The service system of fire weather Index Forecast was developed.
The relationship of fire and weather factors was analysed by using of meteorological data and 1443 fire events at Zhenjiang city of Jiangsu province in seven years.Fire weather type was divided and fire weather index was given.Then,the stepwise regression equation of index forecast of fire weather at Zhenjiang was established by using of T106 products.The forecast accuracy of the operational experiment in two months is 83.6%.The service system of fire weather Index Forecast was developed.
2000, 26(12):49-51.
DOI: 10.7519/j.issn.1000-0526.2000.12.013
Abstract:
Based upon the feature of spread of pollen in the atmosphere,suitable sites and technique for pollen observation were chosen.The technical know-how about the operation procedures on exposing the microscope slide in the air,pollen dying and counting under microscope in the pollen measurement was introduced briefly.Several examples were presented on how to identify the different types of pollen based on different features of pollen,occurred in spring season in Beijing areas.
Based upon the feature of spread of pollen in the atmosphere,suitable sites and technique for pollen observation were chosen.The technical know-how about the operation procedures on exposing the microscope slide in the air,pollen dying and counting under microscope in the pollen measurement was introduced briefly.Several examples were presented on how to identify the different types of pollen based on different features of pollen,occurred in spring season in Beijing areas.
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ISSN:1000-0526 CN:11-2282/P