针对《X射线探伤机》检定规程(JJG 40-2001)的要求,研制了一套X射线探伤机的检定装置。该系统主要基于空腔电离理论测量X射线辐射剂量,研制了0.6cc、600cc电离室和监测用特殊探测器(Monitor Special Detector,MSD),主要用于X射线探伤机...针对《X射线探伤机》检定规程(JJG 40-2001)的要求,研制了一套X射线探伤机的检定装置。该系统主要基于空腔电离理论测量X射线辐射剂量,研制了0.6cc、600cc电离室和监测用特殊探测器(Monitor Special Detector,MSD),主要用于X射线探伤机空气比释动能率、辐射角、重复性等参数的检定。展开更多
In this paper, a generalized layered model for radiation transfer in canopy with high vertical resolution is developed. Differing from the two-stream approximate radiation transfer model commonly used in the land surf...In this paper, a generalized layered model for radiation transfer in canopy with high vertical resolution is developed. Differing from the two-stream approximate radiation transfer model commonly used in the land surface models, the generalized model takes into account the effect of complicated canopy morphology and inhomogeneous optical properties of leaves on radiation transfer within the canopy. In the model, the total leaf area index （LAI） of the canopy is divided into many layers. At a given layer, the influences of diffuse radiation angle distributions and leaf angle distributions on radiation transfer within the canopy are considered. The derivation of equations serving the model are described in detail, and these can deal with various diffuse radiation transfers in quite broad categories of canopy with quite inhomogeneons vertical structures and uneven leaves with substantially different optical properties of adaxial and abaxial faces of the leaves. The model is used to simulate the radiation transfer for canopies with horizontal leaves to validate the generalized model. Results from the model are compared with those from the two-stream scheme, and differences between these two models are discussed.展开更多
文摘针对《X射线探伤机》检定规程(JJG 40-2001)的要求,研制了一套X射线探伤机的检定装置。该系统主要基于空腔电离理论测量X射线辐射剂量,研制了0.6cc、600cc电离室和监测用特殊探测器(Monitor Special Detector,MSD),主要用于X射线探伤机空气比释动能率、辐射角、重复性等参数的检定。
文摘In this paper, a generalized layered model for radiation transfer in canopy with high vertical resolution is developed. Differing from the two-stream approximate radiation transfer model commonly used in the land surface models, the generalized model takes into account the effect of complicated canopy morphology and inhomogeneous optical properties of leaves on radiation transfer within the canopy. In the model, the total leaf area index （LAI） of the canopy is divided into many layers. At a given layer, the influences of diffuse radiation angle distributions and leaf angle distributions on radiation transfer within the canopy are considered. The derivation of equations serving the model are described in detail, and these can deal with various diffuse radiation transfers in quite broad categories of canopy with quite inhomogeneons vertical structures and uneven leaves with substantially different optical properties of adaxial and abaxial faces of the leaves. The model is used to simulate the radiation transfer for canopies with horizontal leaves to validate the generalized model. Results from the model are compared with those from the two-stream scheme, and differences between these two models are discussed.
