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981.
针对焊缝跟踪传感器的研究和探索 总被引:3,自引:0,他引:3
焊接在工业中占有极其重要的地位,应用焊缝跟踪的传感器对保证焊接质量有着不可估量的作用。对利用何种传感器有利于降低成本的探讨是很有意义的。 相似文献
982.
The paper presents a total quality management (TQM) framework combining the concepts underlying the notions of total quality control (TQC), Just in Time (JIT), manufacturing resource planning (MRP), and quality control circles (QCCs). An integrative model, in which these notions and the related issues are complementarily connected on the same logical plane is presented and it is argued that this is akin to the total systems intervention (TSI) approach in its endeavor to seek manufacturing excellence. It also has similarities to creative problem solving, especially with regard to corporate strategy, but here with an emphasis on the role of manufacturing. However, TQM is an idea of its own, and not a conceptual derivative of systems theory. 相似文献
984.
After load instability, a passage of homogeneous strain ε can be still continued in superplastic tensile deformation. But untill now, no one has given the precise value of ε corresponding to actual materials, neither in experimental measurements nor in theoretical calculations. Using the elaborate experimental measuring methods of m value and its function expressions, the note first gives the method to determine homogeneous ε, and the homogeneous ε value of typical superplastic alloy Zn-5% Al under 18℃ and 340℃ respectively. 相似文献
985.
用预制裂纹的CHARPY试样在装备有载荷、位移传感器及微型计算机的冲击试验机上测定了PCrNi3MoVA钢的动态断裂性能,比较了不同冲击速度,不同载面尺寸的试样对K_(Id)的影响,并测出了低温-40℃时的K_(Id)值. 相似文献
986.
伟晶状红柱石矿床,产于中元古界小寨沟组下段,含石榴石、十字石炭质黑云母片岩和炭质黑云母石英片岩中.矿体呈层状、透镜状,共有六层,具有一定层位.矿体中红柱石晶体粗大,有的长达30cm,横断面直径达5-7cm,各晶体均沿片理面定向排列.矿区内未见花岗岩体出露,矿区外围虽有花岗岩体分布,但距离矿体很远,矿体并不受岩体接触带控制.根据矿体形状、产状特征,红柱石矿床是在区域变质过程中,由于变质热液的参加,使铝土质岩层发生重组合和重结晶作用而形成了伟晶状红柱石矿床. 相似文献
987.
Lin Jiawei Cheng Huansheng Zhang Zhengquan Zhang Bin Feng Songlin Song Jian Gao Menghe Zhu Dan 《自然科学进展(英文版)》2007,17(11):1348-1356
This paper reports the study of ancient potteries unearthed from the Guangfulin site in Shanghai. From the external features of these potteries, archeologists can classify them into two different cultural types: Liangzhu culture (local culture) and a new culture which might be derived elsewhere, but they can not recognize whether they were produced in the same place. Proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA) were used to measure the chemical compositions of the samples and the results were analyzed using multivariate statistics. We found that the two methods can complement each other and their database can be mutually referenced in the study of ancient potteries. Experimental results show that the compositions of the potteries from the two cultural types are different, which means that the materials for ancient potteries of new culture originate from elsewhere. This supports the archaeologists’ speculation that a group of ancient people migrated to Shanghai from some other places 4000 years ago. 相似文献
988.
1 .INTRODUCTIONRecentinformation-theoretic results haveshownthat multi-ple-input multiple-output ( MI MO) channels have a greatpotential to i mprove spectral efficiency in rich scatteringwireless channels[1 ,2].Si multaneously,orthogonal frequen-cy division multiplexing (OFDM) has gained anincreasinginterest as a promisingalternativeforfuture highrate wide-band wireless systems because of its lowcomplexity signalprocessingto counteract frequency selectivity. The combi-nationof MI MOsy… 相似文献
989.
教育是人与人心灵上最微妙的接触,教师的人格魅力在教学中有不容忽视的作用,因此,教师要多方努力,不断追求人格完善. 相似文献
990.