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Difference in Canopy and Air Temperature as an Indicator of Grassland Water Stress
water stress indicator air temperature canopy temperature soil moisture grassland vapour pressure deficit actual evapotranspiration
2015/1/28
In 2003–2005 in conditions of the moderately warm region of the Třeboň Basin (Czech Republic) the difference between canopy temperature (Tc) and air temperature at 2 m (Ta) was tested as an indic...
旱后复水对水稻生长的后效影响（Aftereffects of Rewatering after Water Stress on the Rice Growth）
水稻 水分胁迫 复水 后效性
2010/12/29
通过盆栽和测坑试验，研究了水分胁迫后复水对水稻生育后期的后效性影响。结果表明：水稻前期旱后复水后效性明显，尤以分蘖末期短历时重旱、拔节初期短历时轻旱后效性最佳。前期适度的胁迫后复水使水稻后期保持了较大的光合面积，明显降低生育后期叶绿素的降解，使功能叶在生育后期维持较高的光合效率，有利于干物质累积。
水泵疲劳寿命预测中应力计数算法研究（Counting Method of Stress and Application in Fatigue Life Prediction of Pump）
水泵 疲劳寿命 寿命预测 循环计数
2010/12/28
提出了水泵零件疲劳寿命预测的主要思路，讨论了疲劳寿命预测的关键算法——应力计数算法。针对传统应力计数算法存在应力循环提取失效的缺陷，引入临界净应力的概念，提出了对传统计数算法的改进措施。并将改进后的应力计数算法应用于一台轴流泵叶轮的疲劳寿命预测；同时结合该算例，详细说明了二维概率Miner准则疲劳寿命预测的关键步骤。
圆管表面斜裂纹应力强度因子和临界裂纹长度仿真分析（Simulation of Stress Intensity Factors and Critical Crack Length of Surface Oblique Crack on Round Tube）
表面斜裂纹 应力强度因子 临界裂纹长度 应变能密度
2010/12/28
针对圆管表面斜裂纹，建立基于弹性断裂理论和复变函数理论的计算模型。研究圆管表面斜裂纹发生扩展时临界状态所对应的应力强度因子和裂纹临界尺寸在各种相关因素影响下的变化规律。以I、II型复合裂纹为例，采用应变能密度理论对其进行了分析。对开裂角、裂纹所处角度及裂纹的几何尺寸等因素的影响进行仿真计算。得到裂纹所处角度对复合型裂纹两个应力强度因子影响的曲线，并对其影响的程度进行了比较。另外，对裂纹所处角度和开...
Using meteorological data to determine the risk of heat stress
laying hens air temperature air humidity evaporation cooling temperature-humidity index
2010/2/26
This paper first proposes a technique of computing air temperature and humidity in stables based on outdoor air parameters and biological production of animals. The computation technique is outlined. ...
水分胁迫及复水对水稻冠层结构的补偿效应（Compensation Effects of Water Stress and Rewatering on the Structure of Rice Canopy）
水稻 水分胁迫 复水 冠层结构 补偿效应
2009/7/20
通过盆栽和测坑试验，研究了水分胁迫及复水对水稻冠层结构的补偿影响。结果表明：水分胁迫在抑制水稻茎秆、叶片、叶面积延伸生长的同时，能有效地诱导冠层结构，为旱后复水补偿效应的产生提供条件。旱后复水促进了后期穗节的伸长、延缓后期叶片衰老速率、苗后期胁迫使作物对再次受旱的适应能力增强。但补偿效应是有条件的，苗后期重旱和拔节初期轻旱补偿效应最佳，应避免两阶段连旱和拔节期重旱。 Research was ca...
Assessing Crop Water Stress and Irrigation Scheduling in Cotton Through Use of Infrared Thermometry Technique
Crop Water Stress Irrigation Scheduling Cotton Infrared Thermometry Technique
2009/1/22
Crop Water Strees Index (CWSI), based on canopy temperature which can be measured through use of an infrared thermometer, can be used to quantify crop water stress. However, the use of this index on f...
Utilisation of the method of stress limit for designing the motion screw dimensions
Euler Tetmayer motion screw slenderness ratio stress screw drift
2008/2/27
A design of the motion screw using the method of stress limit is described. Further general formulas are induced to design such kind of screws, applied to an example of 11500 (EN ISO E295) steel made ...