he quantitative studies on structure and cytokinin activity of the cucumber cotyledon expansion reiationshps of 35 urea compounds were conducted using pl1ysico-chemical parameters of the substituents and regression an...he quantitative studies on structure and cytokinin activity of the cucumber cotyledon expansion reiationshps of 35 urea compounds were conducted using pl1ysico-chemical parameters of the substituents and regression analysis,The position-specific hydrophobic,steric and electronic effects of substituents are important to the activity.A certain overlap of the optimum conformation of the ureido structure over Kinetin was observed.The coplanarity is discussed.展开更多
Synthetic aperture radar (SAR) is portrayed as a multiple access channel. An information theory approach is applied to the SAR imaging system, and the information content about a target that can be extracted from its ...Synthetic aperture radar (SAR) is portrayed as a multiple access channel. An information theory approach is applied to the SAR imaging system, and the information content about a target that can be extracted from its radar image is evaluated by the average mutual information measure. A conditional (transition) probability density function (PDF) of the SAR imaging system is derived by analyzing the system and a closed form of the information content is found. It is shown that the information content obtained by the SAR imaging system from an independent sample of echoes will decrease and the total information content obtained by the SAR imaging system will increase with an increase in the number of looks. Because the total average mutual information is also used to define a measure of radiometric resolution for radar images, it is shown that the radiometric resolution of a radar image of terrain will be improved by spatial averaging. In addition, the imaging process and the data compression process for SAR are each treated as an independent generalized communication channel. The effects of data compression upon radiometric resolution for SAR are studied and some conclusions are obtained.展开更多
文摘he quantitative studies on structure and cytokinin activity of the cucumber cotyledon expansion reiationshps of 35 urea compounds were conducted using pl1ysico-chemical parameters of the substituents and regression analysis,The position-specific hydrophobic,steric and electronic effects of substituents are important to the activity.A certain overlap of the optimum conformation of the ureido structure over Kinetin was observed.The coplanarity is discussed.
文摘Synthetic aperture radar (SAR) is portrayed as a multiple access channel. An information theory approach is applied to the SAR imaging system, and the information content about a target that can be extracted from its radar image is evaluated by the average mutual information measure. A conditional (transition) probability density function (PDF) of the SAR imaging system is derived by analyzing the system and a closed form of the information content is found. It is shown that the information content obtained by the SAR imaging system from an independent sample of echoes will decrease and the total information content obtained by the SAR imaging system will increase with an increase in the number of looks. Because the total average mutual information is also used to define a measure of radiometric resolution for radar images, it is shown that the radiometric resolution of a radar image of terrain will be improved by spatial averaging. In addition, the imaging process and the data compression process for SAR are each treated as an independent generalized communication channel. The effects of data compression upon radiometric resolution for SAR are studied and some conclusions are obtained.
