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ヒト-ヒューズ系の相互作用を考慮した下腿弾性エネルギーおよびスティフネスの推定ならびに走運動への応用に関する工学的研究
Get PDF国立大学法人長岡技術科学大学博士（工学）doctoral thesi
Time scale dependent sensitivities of the XinAnJiang model parameters
No full textArticleThe objective of this study was to investigate the sensitivities of the parameters of the XinAnJiang model, hereinafter referred to as XAJ model. The XAJ model is the most popular rainfall-runoff model in China, and widely used all over the world. There were fifteen parameters in the modified XAJ model used in this study. Understanding the sensitivities is undoubtedly crucial for parameter optimization, even for manual calibration by trial and error. A sensitivity analysis technique proposed by Morris was used to analyze parameter sensitivities at time scales of year, month and day. The sensitivities of these parameters were shown to change. At annual scale, the parameters for input data adjustment are most sensitive. On the other hand, the parameters concerning runoff component separation and runoff concentration are sensitive at daily scale. The parameters relating to runoff generation are less sensitive at all three temporal scales. Additionally, strong interactions between the parameters were detected at all three temporal scales. The time scale dependent nature of the sensitivities offers the possibility to design more efficient optimization schemes for automatic model calibration of the XAJ model.journal articl
APPLICATION OF ARIDITY INDEX IN PARAMETER OPTIMIZATION OF THE XINANJIANG MODEL
No full textArticleBased on the sensitivity analysis at annual, monthly and daily scales, a multi-step optimization scheme is designed to optimize parameters in Xinanjiang model with the help of SCEM-UA algorithm. In this scheme, parameters are classified into three groups and optimized group by group at different time scale. In this paper, the attention is focused on the parameters for data adjustment, Cp and Cep, which are optimized in the first step. Instead of optimizing Cp and Cep directly in two dimensional spaces, the concept of aridity index (the ratio of annual potential evaporation to precipitation) is introduced into the optimization process, and proposed a relationship describing Cp and Cep as a function of annual runoff coefficient and pan aridity index (the ratio of annual pan evaporation to precipitation). In this way, the feasible parameter space is narrowed and efficiency of sample points which generated for optimization in SCEM-UA algorithm is improved. In addition, it provides a simplified and quick way to get acceptable values of Cp and Cep when the request of precision is not so strict.journal articl
