期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
应用新方法HOMR-HOM均一化1961~2010年北疆最高和最低气温 被引量:1
1
作者 张延伟 葛全胜 +1 位作者 魏文寿 郑景云 《地理科学》 CSCD 北大核心 2015年第6期765-772,共8页
在实际的气象观察中,受站点迁移、城市化及仪器更换等影响,气象观测数据往往存在不均一性。这种不均一性会掩盖气候变化的真相、造成气候变化诊断结果的失真。因此,观测数据序列均一化具有重要的科学和实际意义。选择1961~2010年期间北... 在实际的气象观察中,受站点迁移、城市化及仪器更换等影响,气象观测数据往往存在不均一性。这种不均一性会掩盖气候变化的真相、造成气候变化诊断结果的失真。因此,观测数据序列均一化具有重要的科学和实际意义。选择1961~2010年期间北疆地区37个气象站点(其中14个站点发生过大的迁移,迁移次数达17次之多),首先以乌鲁木齐站点为例子,说明新的HOMR-HOM方法数据断点检测和数据订正过程。然后,对北疆地区逐日最高气温和最低气温进行均一化处理。结果表明:1新的均一化HOMR-HOM方法能较好的检测断点和订正北疆地区的逐日气温数据;2经过均一化处理,北疆地区最高气温观测数据比均一化后数据高,最低气温观测数据比均一化后数据低。 展开更多
关键词 北疆 homr-HOM 最高气温 最低气温
原文传递
Application of Data Mining Method to Improve the Accuracy of Springback Prediction in Sheet Metal Forming
2
作者 许京荆 张志伟 吴益敏 《Journal of Shanghai University(English Edition)》 CAS 2004年第3期348-353,共6页
A new method was worked out to improve the precision of springback prediction in sheet metal forming by combining the finite element method (FEM) with the data mining (DM) technique. First the genetic algorithm (GA) w... A new method was worked out to improve the precision of springback prediction in sheet metal forming by combining the finite element method (FEM) with the data mining (DM) technique. First the genetic algorithm (GA) was adopted for recognizing the material parameters. Then according to the even design idea, the suitable calculation scheme was confirmed, and FEM was used for calculating the springback. The computation results were compared with experiment data, the difference between them was taken as source data, and a new pattern recognition method of DM called hierarchical optimal map recognition method (HOMR) is applied for summarizing the calculation regulation in FEM. At the end, the mathematics model of the springback simulation was established. Based on the model, the calculation errors of springback can be controlled within 10% compared with the experimental results. 展开更多
关键词 springback prediction pattern recognition genetic algorithm FEM even design idea homr data mining.
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部