Effects of modeling means on properties of monitoring models o spot welding quality

Analyzing and modeling the relation between monitoring information during welding and quality information of the joints is the foundation of monitoring resistance spot welding quality.According to the means of modeling,the known models can be divided into three large categories:single linear regression models,multiple linear regression models and multiple nonlinear models.By modeling the relations between dynamic resistance information and welding quality parameters with different means,this paper analyzes effects of modeling means on performances of monitoring models of resistance spot welding quality. From the test results,the following conclustons can be drawn:By comparison with two other kinds of models,artificial neural network(ANN) model can describe non-linear and high coupling relationship between monitoring information and quality information more reasonably,improve performance of monitoring model remarkably,and make the estimated values of welding quality parameters more accurate and reliable.     

葛洲坝电厂制动器结构性能分析及选型探讨

针对170MW机组制动器制动后复归难、油压顶转子后残油无法排除干净等问题，提出对两台机组制动器进行换型改造。通过对国内几个厂家制动器的调研，给制动器改造选型提供了参考数据。     

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章对1997年在吉林探区东南隆起区应用的气测七参数判别法的原理与判别模型的建立进行了介绍，并对其应用情况进行了客观分析，针对存在的问题将判别模型进行了改进，提高了解符合率，取得了较好的效果，此后，又依据中央坳陷区、佳伊地暂储层特征分别建立了判别模型。最后对三个地区的应用进行了归纳总结，指出该方法存在的问题以及下一步工作建议。     

甲基丙烯酸2—乙基已酯合成的中试研究

采用酯交换工艺，对甲基丙烯酸2-乙基已酯（2-EHMA）的合成进行了100t/a级中间放大试验研究。确定了酯交换法生产2-EHMA工艺流程和各种工艺条件，试验结果的重复性好，所选用的催化剂和阻聚剂体系活性高且可以反复多次回用，产品收率和纯度可分别达98%和99.5%以上，各项技术指标达到或优于小试结果。     

水采高压系统注水软化煤层的可行性研究

针对目前水采高压供水系统存在的问题进行了透彻的分析，提出了采用水采高压供水系统进行注水软化煤层的方案设想，并从技术和经济上进行了可行性分析。对水采矿井实现节能降耗具有一定的参考价值。