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简述了LCR测量仪的测量原理,研究了LCR测试仪中元件测试的几种端接技术的特点、误差及阻抗适用范围。每种端接技术的连接方法各有优缺点,必须根据被测元(DUT)的阻抗和要求的测量精度,选择合适的连接方法。 相似文献
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本文根据Lacoste-Romberg(G)型重力仪(简称LCR(G)型重力仪)读数系统的结构特征,首次导出了LCR(G)型重力仪的相对重力公式和格值公式。并根据文[3]中提供的格值表,用本文导出的公式进行最小二乘曲线拟合,得到有关参数,利用所求参数计算了相应的格值,与文[3]中提供的格值符合得很好。 相似文献
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以预设不同尺度裂缝的水泥砂浆块体和无裂缝水泥砂浆块体等三组试件为试验研究对象,提出利用MT4090 LCR测量仪直接测试试件的复阻抗幅模在z和相角φ、等效串联电阻ESR和电容Cs ,并与基于交流阻抗谱法得到的测试数据进行比较。试验研究表明:基于交流阻抗谱法和用MT4090 LCR测量仪得到的数据非常接近,具有同样的规律和特征;有裂缝的水泥砂浆试件的z 、ESR值明显大于无裂缝水泥砂浆试件,且随裂缝长度增大而增大,Cs值变化规律相反,这3个参数可以作为裂缝检测及监测的测试参数;用MT4090 LCR测量仪有望真正实现快速、简便的混凝土裂缝的检测与实时监测;验证了水泥砂浆试件呈现电容性,且容抗值相对ESR值较小。 相似文献
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Kaoru Inoue Shigeru Yamamoto Toshimitsu Ushio Toshiji Kato 《Electrical Engineering in Japan》2006,154(3):48-55
In this paper, we analyze stability of a time‐varying system represented by second‐order vector differential equations based on the characteristics of their coefficient matrices. New sufficient conditions for asymptotic stability of the equilibrium points are derived. Then, an asymptotic stabilizing control method of parametric LCR resonant system is discussed by using the obtained sufficient conditions. A method synchronizing two parametric LCR resonant systems is also given. The effectiveness of the results is illustrated by numerical examples. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(3): 48–55, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20142 相似文献
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Y. Qi A. R. Zbrzezny M. Agia R. Lam H. R. Ghorbani P. Snugovsky D. D. Perovic J. K. Spelt 《Journal of Electronic Materials》2004,33(12):1497-1506
Leadless chip resistor (LCR) assemblies were manufactured using both traditional tin-lead (Sn37Pb) and lead-free (Sn3.8Ag0.7Cu)
solders. The leadfree test vehicles were assembled using three different cooling rates: 1.6°C/sec, 3.8°C/sec, and 6.8°C/sec.
They were then exposed to accelerated thermalcycling (ATC) tests between 0°C and 100°C with a 10–14°C/min ramp rate and a
5-min dwell time. The test results indicated that these lead-free solder joints had better creep-fatigue performance than
the tin-lead solder joints. The LCR built with the medium cooling rate showed the longest fatigue life compared with the resistors
built with the normal cooling rate of 1.6°C/sec and the higher cooling rate 6.8°C/sec. The number of cycles to failure was
significantly correlated to the void defect rate. Failure analyses were done using cross-sectioning methods and scanning electron
microscopy (SEM). Finite-element models were built to analyze the inelastic, equivalent strain range in solder joints subjected
to thermal-cycling conditions with different degrees of solder wetting. The results indicated that poor wetting increases
strains throughout the joint significantly, which is in accordance with the ATC results. 相似文献
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在利用低频同轴反射法(LCR)进行材料吸波性能的测试过程中,经常会使用矢量网络分析仪的GATE功能来滤除干扰因素对测试结果的影响。本文通过对测试原理的阐述和不同吸波材料的测试结果的分析,说明了如何合理地设置矢量网络分析仪的GATE以及测试过程中应该注意的问题。 相似文献
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阐述武钢CSP连铸机液芯压下扇形段的构成、控制原理、功能作用,介绍武钢CSP连铸液芯压下技术(LCR)的应用实践、常见故障及处理措施,并指出连铸液芯压下技术的进一步开发应用方向。 相似文献