The main goal of this study was to assess the long-term impacts of global warming perturbation on water resources of the Kaidu River Basin in Northwest China. Temperature, precipitation and hydrology data during the p...The main goal of this study was to assess the long-term impacts of global warming perturbation on water resources of the Kaidu River Basin in Northwest China. Temperature, precipitation and hydrology data during the past 29 years from 1979 to 2007 were collected and analyzed using parametric and non-parametric methods, the connection between temperature and precipitation by the combination of grey correlation analysis method and the hypothesis testing for trend of climate change. The results show a high increase in temperature in the study area as well as an extreme and highly variable hydrological regime in this region, where flash floods can exceed the total runoff from a sequence of years. These variations may be due to the geographical location of the Kaidu River Basin in arid zone. It also reveals that precipitation has a much greater impact on stream flow than that of temperature. The development of new approaches was proposed as responses to climate change in this arid region.展开更多
The characteristics of the normal equation created in recovering the Earth gravity model （EGM） by least-squares （LS） adjustment from the in-situ disturbing potential is discussed in detail. It can be concluded tha...The characteristics of the normal equation created in recovering the Earth gravity model （EGM） by least-squares （LS） adjustment from the in-situ disturbing potential is discussed in detail. It can be concluded that the normal equation only depends on the orbit, and the choice of a priori gravity model has no effect on the LS solution. Therefore, the accuracy of the recovered gravity model can be accurately simulated. Starting from this point, four sets of disturbing potential along the orbit with different level of noise were simulated and were used to recover the EGM. The results show that on the current accuracy level of the accelerometer calibration, the accuracy of the EGM is not sufficient to reflect the time variability of the Earth＇s gravity field, as the dynamic method revealed.展开更多
Using the standard Painlevé analysis and the perturbative method, the Painlevé test for the logarithmic branch is investigated. Nine arbitrary functions are obtained and the Baecklund transformation of the l...Using the standard Painlevé analysis and the perturbative method, the Painlevé test for the logarithmic branch is investigated. Nine arbitrary functions are obtained and the Baecklund transformation of the logarithmic branch is given. Using the new type Baecklund transformation, many exact solutions are obtained.展开更多
基金supported by the State Key Development Program for Basic Research of China (973 program (Grant No. 2010CB951002)the Natural Sciences Foundation of China (Grant No. 40871027)+1 种基金the Project from Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone (Grant No. XJYS0907-2011-03)the Knowledge Innovation project of Chinese Academy of Science (KZCX2-YW-334) for financial supports
文摘The main goal of this study was to assess the long-term impacts of global warming perturbation on water resources of the Kaidu River Basin in Northwest China. Temperature, precipitation and hydrology data during the past 29 years from 1979 to 2007 were collected and analyzed using parametric and non-parametric methods, the connection between temperature and precipitation by the combination of grey correlation analysis method and the hypothesis testing for trend of climate change. The results show a high increase in temperature in the study area as well as an extreme and highly variable hydrological regime in this region, where flash floods can exceed the total runoff from a sequence of years. These variations may be due to the geographical location of the Kaidu River Basin in arid zone. It also reveals that precipitation has a much greater impact on stream flow than that of temperature. The development of new approaches was proposed as responses to climate change in this arid region.
基金Funded by the National Natural Science Foundation of China （No.40274004）, and the Open Fund of Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, China （No. 06-09）. The authors are grateful to Prof. CHAO Dingbo for his critical comments and also thank Dr. Dadzie very much for his proof-reading.
文摘The characteristics of the normal equation created in recovering the Earth gravity model （EGM） by least-squares （LS） adjustment from the in-situ disturbing potential is discussed in detail. It can be concluded that the normal equation only depends on the orbit, and the choice of a priori gravity model has no effect on the LS solution. Therefore, the accuracy of the recovered gravity model can be accurately simulated. Starting from this point, four sets of disturbing potential along the orbit with different level of noise were simulated and were used to recover the EGM. The results show that on the current accuracy level of the accelerometer calibration, the accuracy of the EGM is not sufficient to reflect the time variability of the Earth＇s gravity field, as the dynamic method revealed.
文摘Using the standard Painlevé analysis and the perturbative method, the Painlevé test for the logarithmic branch is investigated. Nine arbitrary functions are obtained and the Baecklund transformation of the logarithmic branch is given. Using the new type Baecklund transformation, many exact solutions are obtained.
