By comparative analysis on the meteorological conditions and occurrences of rice planthoppers in Guilin of Guangxi during recent 5 years,the temperature,precipitation,wind direction,wind velocity,humidity were chosen ...By comparative analysis on the meteorological conditions and occurrences of rice planthoppers in Guilin of Guangxi during recent 5 years,the temperature,precipitation,wind direction,wind velocity,humidity were chosen as the factors that affected the migration of rice planthopper in Guilin.Thinking of meteorological conditions and injurious number in early period,regression analysis method was used to establish the work system for grade forecast of meteorological conditions that affected the migration of rice planthopper.The forecast factors and targets were divided as 5 grades in the work system.Using one-week's weather forecast conclusion that local observatory had published,whether the meteorological conditions and injurious number were favorable or not was analyzed synthetically.The meteorological conditions grades that affected the migration of rice planthopper for each day in future 1-7 days were predicted.This is a practical forecast work system and the forecast accuracy for each day is larger than 70%.The work system has positive function in the manufacture practice.展开更多
Based on the fire and meteorological data of forest and grassland in Inner Mongolia in recent 30 years,a forest and grassland fire risk grade forecast model is established,and a refined forest and grassland fire risk ...Based on the fire and meteorological data of forest and grassland in Inner Mongolia in recent 30 years,a forest and grassland fire risk grade forecast model is established,and a refined forest and grassland fire risk level forecast system based on smart grid is developed. The results show that predictors are determined about forest and grassland fire risk grade,such as precipitation,minimum relative humidity,maximum temperature,maximum wind speed,number of sunny or rainy days,and forest and grassland combustible stock. According to fire risk division conclusion,forest and grassland areas are divided into 5 forecast areas. By using discriminant analysis and weighted factor overlay method,an elaborate fire risk grade forecast model is established in different forecast areas of Inner Mongolia forest and grassland. By using smart grid forecast field data,an elaborate fire risk grade forecasting system is established for making fire risk grade forecast during 24,48 and 72 h.展开更多
The objective of this study is to improve the statistical modeling for the ternary forecast of heavy snowfall in the Honam area in Korea. The ternary forecast of heavy snowfall consists of one of three values, 0 for l...The objective of this study is to improve the statistical modeling for the ternary forecast of heavy snowfall in the Honam area in Korea. The ternary forecast of heavy snowfall consists of one of three values, 0 for less than 50 mm, 1 for an advisory （50-150 ram）, and 2 for a warning （more than 150 mm）. For our study, the observed daily snow amounts and the numerical model outputs for 45 synoptic factors at 17 stations in the Honam area during 5 years （2001 to 2005） are used as observations and potential predictors respectively. For statistical modeling and validation, the data set is divided into training data and validation data by cluster analysis. A multi-grade logistic regression model and neural networks are separately applied to generate the probabilities of three categories based on the model output statistic （MOS） method. Two models are estimated by the training data and tested by the validation data. Based on the estimated probabilities, three thresholds are chosen to generate ternary forecasts. The results are summarized in 3 × 3 contingency tables and the results of the three-grade logistic regression model are compared to those of the neural networks model. According to the model training and model validation results, the estimated three-grade logistic regression model is recommended as a ternary forecast model for heavy snowfall in the Honam area.展开更多
利用森林火险指数仪进行森林火险实时监测,以ArcGIS Engine10作为开发平台、以SQL server 2005作为数据库设计开发了森林火险实时预警系统。系统构建包括森林火险指数仪的选址、火险指数和火险等级计算及专题图制作、信息发布。系统能...利用森林火险指数仪进行森林火险实时监测,以ArcGIS Engine10作为开发平台、以SQL server 2005作为数据库设计开发了森林火险实时预警系统。系统构建包括森林火险指数仪的选址、火险指数和火险等级计算及专题图制作、信息发布。系统能以简明的电子地图和二维表,直观显示火险指数、火险等级的监测结果及其空间分布特征。以四川仁寿为例,展示了森林火险预警功能的实现过程和效果。结果表明,预警系统能够对森林火险进行实时监测与及时预警,有利于对森林火灾进行合理预防。展开更多
基金Supported by The Project of Guilin Science and Technology in Guangxi (2009011405)
文摘By comparative analysis on the meteorological conditions and occurrences of rice planthoppers in Guilin of Guangxi during recent 5 years,the temperature,precipitation,wind direction,wind velocity,humidity were chosen as the factors that affected the migration of rice planthopper in Guilin.Thinking of meteorological conditions and injurious number in early period,regression analysis method was used to establish the work system for grade forecast of meteorological conditions that affected the migration of rice planthopper.The forecast factors and targets were divided as 5 grades in the work system.Using one-week's weather forecast conclusion that local observatory had published,whether the meteorological conditions and injurious number were favorable or not was analyzed synthetically.The meteorological conditions grades that affected the migration of rice planthopper for each day in future 1-7 days were predicted.This is a practical forecast work system and the forecast accuracy for each day is larger than 70%.The work system has positive function in the manufacture practice.
基金Supported by Scientific and Technological Project of Inner Mongolia Autonomous Region (2020GG0016)。
文摘Based on the fire and meteorological data of forest and grassland in Inner Mongolia in recent 30 years,a forest and grassland fire risk grade forecast model is established,and a refined forest and grassland fire risk level forecast system based on smart grid is developed. The results show that predictors are determined about forest and grassland fire risk grade,such as precipitation,minimum relative humidity,maximum temperature,maximum wind speed,number of sunny or rainy days,and forest and grassland combustible stock. According to fire risk division conclusion,forest and grassland areas are divided into 5 forecast areas. By using discriminant analysis and weighted factor overlay method,an elaborate fire risk grade forecast model is established in different forecast areas of Inner Mongolia forest and grassland. By using smart grid forecast field data,an elaborate fire risk grade forecasting system is established for making fire risk grade forecast during 24,48 and 72 h.
基金This research was performed for the project "Development of technique for Local Prediction", one of the research and development projects on meteorology and seismology funded by the Korea Meteorological Administration (KMA), 2005.
文摘The objective of this study is to improve the statistical modeling for the ternary forecast of heavy snowfall in the Honam area in Korea. The ternary forecast of heavy snowfall consists of one of three values, 0 for less than 50 mm, 1 for an advisory （50-150 ram）, and 2 for a warning （more than 150 mm）. For our study, the observed daily snow amounts and the numerical model outputs for 45 synoptic factors at 17 stations in the Honam area during 5 years （2001 to 2005） are used as observations and potential predictors respectively. For statistical modeling and validation, the data set is divided into training data and validation data by cluster analysis. A multi-grade logistic regression model and neural networks are separately applied to generate the probabilities of three categories based on the model output statistic （MOS） method. Two models are estimated by the training data and tested by the validation data. Based on the estimated probabilities, three thresholds are chosen to generate ternary forecasts. The results are summarized in 3 × 3 contingency tables and the results of the three-grade logistic regression model are compared to those of the neural networks model. According to the model training and model validation results, the estimated three-grade logistic regression model is recommended as a ternary forecast model for heavy snowfall in the Honam area.
文摘利用森林火险指数仪进行森林火险实时监测,以ArcGIS Engine10作为开发平台、以SQL server 2005作为数据库设计开发了森林火险实时预警系统。系统构建包括森林火险指数仪的选址、火险指数和火险等级计算及专题图制作、信息发布。系统能以简明的电子地图和二维表,直观显示火险指数、火险等级的监测结果及其空间分布特征。以四川仁寿为例,展示了森林火险预警功能的实现过程和效果。结果表明,预警系统能够对森林火险进行实时监测与及时预警,有利于对森林火灾进行合理预防。
