为了构建日尺度的冬小麦阴湿害评估方法,综合应用基于HP滤波趋势产量分解法的安徽省冬小麦历年气象减产率数据、地面气象观测数据,以日尺度的标准化前期降水蒸散指数、日照百分率为阴湿害关键影响因子,通过有效阴湿害积与过程敏感性耦...为了构建日尺度的冬小麦阴湿害评估方法,综合应用基于HP滤波趋势产量分解法的安徽省冬小麦历年气象减产率数据、地面气象观测数据,以日尺度的标准化前期降水蒸散指数、日照百分率为阴湿害关键影响因子,通过有效阴湿害积与过程敏感性耦合方式,构建冬小麦全生育期阴湿害综合指数(overcast and waterlogging composite index,OWCI),并选取阴湿害典型年样本,分别以Logistic曲线敏感性、等敏感性两种方法计算的阴湿害综合气象指数OWCIs、OWCIe为自变量、气象减产率(△Y)为因变量进行相关性分析,比较、验证两种方法在冬小麦阴湿害评估中的差异性与适用性。结果表明,△Y与两种方法的阴湿害综合气象指数均呈显著二次曲线相关,R^2分别为0.843、0.805;检验样本的△Y实测值与两种方法模拟值的R^2分别达0.685、0.573。对两种方法比较,Logistic曲线敏感性法建模的拟合性、误差、检验效果均优于等敏感性法,其气象减产率的均方根误差从7.78%下降到6.97%。应用Logistic曲线敏感性法模拟的2016年冬小麦阴湿害灾损率值与调查值基本吻合。反演计算的1981-2010年灾损率气候态均值南高北低,符合安徽省实际分布型,但2011年以来的灾损率均值普遍高于30年气候态均值,可见近年来阴湿害影响有加重趋势。因此,基于有效阴湿害积与过程敏感性耦合应用构建的冬小麦生长过程阴湿害灾损评估模型,能差异化表征不同阶段的阴湿害影响贡献,可应用于冬小麦阴湿害影响评估。展开更多
For Gu-Ag alloy, an important parameter called workability in the forming process of materials can be evaluated by processing maps yielded from the stress-strain data generated by hot compression tests at temperatures...For Gu-Ag alloy, an important parameter called workability in the forming process of materials can be evaluated by processing maps yielded from the stress-strain data generated by hot compression tests at temperatures of 700-850 °C and strain rates of 0.01-10 s-1. And at the true strain of 0.15, 0.35 and 0.55, respectively, the responses of strain-rate sensitivity, power dissipation efficiency and instability parameter to temperature and strain rate were studied. Instability maps and power dissipation maps were superimposed to form processing maps, which reveal the determinate regions where individual metallurgical processes occur and the limiting conditions of flow instability regions. Furthermore, the optimal processing parameters for bulk metal working are identified clearly by the processing maps.展开更多
文摘为了构建日尺度的冬小麦阴湿害评估方法,综合应用基于HP滤波趋势产量分解法的安徽省冬小麦历年气象减产率数据、地面气象观测数据,以日尺度的标准化前期降水蒸散指数、日照百分率为阴湿害关键影响因子,通过有效阴湿害积与过程敏感性耦合方式,构建冬小麦全生育期阴湿害综合指数(overcast and waterlogging composite index,OWCI),并选取阴湿害典型年样本,分别以Logistic曲线敏感性、等敏感性两种方法计算的阴湿害综合气象指数OWCIs、OWCIe为自变量、气象减产率(△Y)为因变量进行相关性分析,比较、验证两种方法在冬小麦阴湿害评估中的差异性与适用性。结果表明,△Y与两种方法的阴湿害综合气象指数均呈显著二次曲线相关,R^2分别为0.843、0.805;检验样本的△Y实测值与两种方法模拟值的R^2分别达0.685、0.573。对两种方法比较,Logistic曲线敏感性法建模的拟合性、误差、检验效果均优于等敏感性法,其气象减产率的均方根误差从7.78%下降到6.97%。应用Logistic曲线敏感性法模拟的2016年冬小麦阴湿害灾损率值与调查值基本吻合。反演计算的1981-2010年灾损率气候态均值南高北低,符合安徽省实际分布型,但2011年以来的灾损率均值普遍高于30年气候态均值,可见近年来阴湿害影响有加重趋势。因此,基于有效阴湿害积与过程敏感性耦合应用构建的冬小麦生长过程阴湿害灾损评估模型,能差异化表征不同阶段的阴湿害影响贡献,可应用于冬小麦阴湿害影响评估。
基金Project(CSTC2009BA4065) supported by the Chongqing Natural Science Foundation,China
文摘For Gu-Ag alloy, an important parameter called workability in the forming process of materials can be evaluated by processing maps yielded from the stress-strain data generated by hot compression tests at temperatures of 700-850 °C and strain rates of 0.01-10 s-1. And at the true strain of 0.15, 0.35 and 0.55, respectively, the responses of strain-rate sensitivity, power dissipation efficiency and instability parameter to temperature and strain rate were studied. Instability maps and power dissipation maps were superimposed to form processing maps, which reveal the determinate regions where individual metallurgical processes occur and the limiting conditions of flow instability regions. Furthermore, the optimal processing parameters for bulk metal working are identified clearly by the processing maps.
