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在某项测量课题中,为准确测量大批量待测点的大地坐标,利用"大地测量型GPS"准确地测量出基准控制点,并利用"全站仪"测量其余标志点相对控制点的坐标,在通过计算得出这些点的大地坐标。通过该方法,避免了繁琐的测量过程,使数据测量和处理的时间周期大大缩短。 相似文献
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本文以实验为基础,提出在工具显微镜类仪器中,为了提高测量精度,应如何正确使用光(门东)。 相似文献
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For exploring the biological effect of space environment on different genotype of rice seeds, the cytological effects of M1 generation after space flight were studied. Twelve different genotypes of rice seeds which belong to different climate ecotype (early, medium and late) of indica and japonica were onboard "Shenzhou 4" spaceship for 162 h. After recovered the total number of mitosis cells and chromosomal aberration were observed. In all the lines the mitotic index (MIs) of space flight are much higher than control, which indicates the stimulate effect of space environment. The cell rate of chromosomal aberration (CRCA) of space flight is also much higher than control, but varies from line to line. It indicates that biological effect of space environment on rice seed dependents not only on flight duration but also on rice genotype. The radiosensitivities of different lines were also discussed according to CRCAs. 相似文献
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本文介绍了用脉冲细分法测量机械构件的运动误差、转速、速度和加速度的测量原理,分析了可能产生的误差及提高测量精度的方法,并给出了相应的逻辑设计框图。该仪器可测量机床的扭振和爬行,可以进行传动链分析及机构的运动学和动力学分析。 相似文献