The study area has located on Atrak river basin in the Iran-Turkmenistan border zone that is the greatest river on the southeastern margin of Caspian Sea. The study area was divided into 56 sub-basins and then T facto...The study area has located on Atrak river basin in the Iran-Turkmenistan border zone that is the greatest river on the southeastern margin of Caspian Sea. The study area was divided into 56 sub-basins and then T factors were calculated for all streams of the Atrak river. T factor is a geomorphic index for tilting identification by active tectonics. Our results show that, there are low, moderate and high relative tectonic activities levels. Low relative tectonic activities level has been found in sub-basins No. 1, 2, 3, 4, 10, 23, 25, 41 and 51, moderate relative tectonic activities level has been found in sub-basins No. 5, 6, 7, 8, 13, 14, 17, 18, 19, 20, 21, 24, 28, 29, 30, 31, 32, 34, 35, 39, 40, 42, 43, 46, 47,48, 49, 50, 52, 53, 55 and 56 and high relative tectonic activities level has been found in sub-basins No. 9, 11, 12, 15, 16, 22, 26, 27, 33, 36, 37, 38, 44, 45 and 54. Also, most part of the study area has got moderate tectonic activity that it is compatible with its tectonic setting on the Kopetdagh belt in Iran. It is shows that some sub-basins on the western parts of study area that river has got west-east trending, are more active. But, some sub-basins on the eastern parts of study area that river has got northwest-southeast trending, are less active. It means that migration direction of the most streams are toward north and south and the major faults and folds in the western parts of study area caused river tilting be perpendicular to structural trend. This variation along the most important river on the northeastern part of Iran was analyzed for the first time in this research.展开更多
增益噪声温度比(Gain to Noise Temperature Ratio,G/T)是衡量卫星地面接收系统性能的关键指标,其测量精度直接影响系统性能评估的有效性。为提高G/T值的测量精度,系统阐述了利用射电源进行G/T值测试的原理和方法,提出了射电源大气吸收...增益噪声温度比(Gain to Noise Temperature Ratio,G/T)是衡量卫星地面接收系统性能的关键指标,其测量精度直接影响系统性能评估的有效性。为提高G/T值的测量精度,系统阐述了利用射电源进行G/T值测试的原理和方法,提出了射电源大气吸收修正因子、波束展宽修正因子、射电源流量随时间变化修正因子的精确计算模型,并给出了射电源通量密度曲线及修正因子曲线。在此基础上,利用月亮和仙后座A对中等口径天线进行G/T值测量,系统分析了G/T值的测量误差,验证了所提计算模型的有效性,为提高G/T值测量的精确性与可靠性提供了科学依据和实践指导。展开更多
文摘The study area has located on Atrak river basin in the Iran-Turkmenistan border zone that is the greatest river on the southeastern margin of Caspian Sea. The study area was divided into 56 sub-basins and then T factors were calculated for all streams of the Atrak river. T factor is a geomorphic index for tilting identification by active tectonics. Our results show that, there are low, moderate and high relative tectonic activities levels. Low relative tectonic activities level has been found in sub-basins No. 1, 2, 3, 4, 10, 23, 25, 41 and 51, moderate relative tectonic activities level has been found in sub-basins No. 5, 6, 7, 8, 13, 14, 17, 18, 19, 20, 21, 24, 28, 29, 30, 31, 32, 34, 35, 39, 40, 42, 43, 46, 47,48, 49, 50, 52, 53, 55 and 56 and high relative tectonic activities level has been found in sub-basins No. 9, 11, 12, 15, 16, 22, 26, 27, 33, 36, 37, 38, 44, 45 and 54. Also, most part of the study area has got moderate tectonic activity that it is compatible with its tectonic setting on the Kopetdagh belt in Iran. It is shows that some sub-basins on the western parts of study area that river has got west-east trending, are more active. But, some sub-basins on the eastern parts of study area that river has got northwest-southeast trending, are less active. It means that migration direction of the most streams are toward north and south and the major faults and folds in the western parts of study area caused river tilting be perpendicular to structural trend. This variation along the most important river on the northeastern part of Iran was analyzed for the first time in this research.
文摘增益噪声温度比(Gain to Noise Temperature Ratio,G/T)是衡量卫星地面接收系统性能的关键指标,其测量精度直接影响系统性能评估的有效性。为提高G/T值的测量精度,系统阐述了利用射电源进行G/T值测试的原理和方法,提出了射电源大气吸收修正因子、波束展宽修正因子、射电源流量随时间变化修正因子的精确计算模型,并给出了射电源通量密度曲线及修正因子曲线。在此基础上,利用月亮和仙后座A对中等口径天线进行G/T值测量,系统分析了G/T值的测量误差,验证了所提计算模型的有效性,为提高G/T值测量的精确性与可靠性提供了科学依据和实践指导。
