Landslides are increasing since the 1980s in Xi'an, Shaanxi Province, China. This is due to the increase of the frequency and intensity of precipitation caused by complex geological structures, the presence of ste...Landslides are increasing since the 1980s in Xi'an, Shaanxi Province, China. This is due to the increase of the frequency and intensity of precipitation caused by complex geological structures, the presence of steep landforms, seasonal heavy rainfall, and the intensifcation of human activities. In this study, we propose a landslide prediction model based on the analysis of intraday rainfall(IR) and antecedent effective rainfall(AER). Primarily, the number of days and degressive index of the antecedent effective rainfall which affected landslide occurrences in the areas around Qin Mountains, Li Mountains and Loess Tableland was established. Secondly, the antecedent effective rainfall and intraday rainfall were calculated from weather data which were used to construct critical thresholds for the 10%, 50% and 90% probabilities for future landslide occurrences in Qin Mountain, Li Mountain and Loess Tableland. Finally, the regions corresponding to different warning levels were identified based on the relationship between precipitation and the threshold, that is; "A" region is safe, "B" region is on watch alert, "C" region is on warning alert and "D" region is on severe warning alert. Using this model, a warning program is proposed which can predict rainfall-induced landslides by means of real-time rain gauge data and real-time geo-hazard alert and disaster response programs. Sixteen rain gauges were installed in the Xi'an region by keeping in accordance with the regional geology and landslide risks. Based on the data from gauges, this model accurately achieves the objectives of conducting real-time monitoring as well as providing early warnings of landslides in the Xi'an region.展开更多
In today＇ s society, there are increasingly more new requirements on English education in local colleges and universities, and also there are some problems to be exposed. A great difference exists between the languag...In today＇ s society, there are increasingly more new requirements on English education in local colleges and universities, and also there are some problems to be exposed. A great difference exists between the language application ability of learners and the actual conditions of teaching; great investments are put by both schools and teachers into teaching, but the teaching quality is not improved and also the teaching effect is not very ideal; the pass rate and excellent rate of CET4 and CET6 are pursued by many Chinese colleges and universities, and the strategy with an ocean of paper and examination-oriented intensive training methods are even applied, so that the internal rules of language teaching are seriously damaged.展开更多
基金financially supported by the National Natural Science Foundation of China (Grant Nos. 41130753 and 41202244)the National Key Fundamental Research Program of China (973) (Grant No. 2014CB744703)China Postdoctoral Science Foundation (Grant No. 2012M521728)
文摘Landslides are increasing since the 1980s in Xi'an, Shaanxi Province, China. This is due to the increase of the frequency and intensity of precipitation caused by complex geological structures, the presence of steep landforms, seasonal heavy rainfall, and the intensifcation of human activities. In this study, we propose a landslide prediction model based on the analysis of intraday rainfall(IR) and antecedent effective rainfall(AER). Primarily, the number of days and degressive index of the antecedent effective rainfall which affected landslide occurrences in the areas around Qin Mountains, Li Mountains and Loess Tableland was established. Secondly, the antecedent effective rainfall and intraday rainfall were calculated from weather data which were used to construct critical thresholds for the 10%, 50% and 90% probabilities for future landslide occurrences in Qin Mountain, Li Mountain and Loess Tableland. Finally, the regions corresponding to different warning levels were identified based on the relationship between precipitation and the threshold, that is; "A" region is safe, "B" region is on watch alert, "C" region is on warning alert and "D" region is on severe warning alert. Using this model, a warning program is proposed which can predict rainfall-induced landslides by means of real-time rain gauge data and real-time geo-hazard alert and disaster response programs. Sixteen rain gauges were installed in the Xi'an region by keeping in accordance with the regional geology and landslide risks. Based on the data from gauges, this model accurately achieves the objectives of conducting real-time monitoring as well as providing early warnings of landslides in the Xi'an region.
文摘In today＇ s society, there are increasingly more new requirements on English education in local colleges and universities, and also there are some problems to be exposed. A great difference exists between the language application ability of learners and the actual conditions of teaching; great investments are put by both schools and teachers into teaching, but the teaching quality is not improved and also the teaching effect is not very ideal; the pass rate and excellent rate of CET4 and CET6 are pursued by many Chinese colleges and universities, and the strategy with an ocean of paper and examination-oriented intensive training methods are even applied, so that the internal rules of language teaching are seriously damaged.
