共查询到20条相似文献,搜索用时 31 毫秒
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金克木先生在谈到交叉科学,边缘科学时提出这个公式。C是从A、B序列或局部中产生出来的,所以说A B=C;但A、B又必须准确构成有效运转的控制系统,C才会出现,所以它不等于各个部分的简单总合,而是一种新值。 现在大学生也很重视交叉科学,但较为普遍地存在一个毛病,即只有广求知识之志,而无综合运 相似文献
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The Doppler modulation system is a principal part of a Mössbauer spectrometer. It includes the Doppler modulator (velocity transducer) and a control system (the modulator driver) which consists of a function generator that produces a reference signal by which the vibrator can be controlled and the error correction circuit that corrects the motion of the vibrator according to the reference signal. The motion of the driver must be identical to the preferred wave shape for the operation of the spectrometer. The aim of the present article is to design and test a low cost lab-built modulator velocity driver for a Mössbauer spectrometer to be used in the constant acceleration (triangular) mode of operation, although it can be used in the other operational modes. A triangular wave is stored in RAM. The axis of the vibrator carries two coils, one for the driving signal and the other for the pickup signal which gives the shape of the motion of the driver (i.e., the actual motion of the source). The stored reference triangular wave is compared with the one from the pickup coil and the difference between them gives an error signal. The error signal will be zero if the motion of the vibrator is identical to that of the stored wave. This error signal is added to the driving pulse in a suitable phase and amplitude in order to obtain a source motion with minimized deviation from its correct value. 相似文献
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《润滑与密封》1977,(3)
我厂是一个生产各种类型磨床的工厂,磨床的液压系统和工件磨削的冷却液都需要大量的机械油和肥皂水。多年来,漏油和漏水成了磨床产品普遍存在的老问题。为了解决这个问题,厂党委成立了三结合治漏小组,并举办了学习班。认识到查“三漏”先要查路线。首先,取得了思想、认识、步骤和行动上的四个统一,接着采取了学查结合、内外结合的办法,厂内发动群众查漏点,提办法;到厂外进行用户访问,听批评,学经验,然后选择批量大的基型产品M1432A 万能外圆磨床作为典型,解剖麻雀,以点带面。在大搞群众运动的同时,又相应建立必要的规章制度,每月重点检查一次,分析一次;每季度抽查一次,解剖一次的工作制度。通过一个阶段的摸索,归纳了治漏的一般做法有两条:一是“堵”,堵塞漏油处,二是“引”,在堵不住的地方,就因势利导,把油 相似文献
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《世界仪表与自动化》2005,9(6):63-63
维博电子生产的WB64系列传感器是一种高性价比的现场隔离模块,采用高性能MCU实现高速数字采集,综合运用DSP技术,实现交流电参数的线形变换、计算和分析,从而获得交流电压、交流电流的真有效值,经A/D转换,形成标准化信号输出。使用本系列传感器可构成高性价比的测控系统。 相似文献
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A/D、D/A接口电路系统设计 总被引:3,自引:0,他引:3
文中论述了模数、数模转换接口系统设计的要求、原则和根据系统要求选择模数、数模芯片,并重点阐述了在系统线路设计时必须考虑的一些问题。 相似文献
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Chen Cichang 《机械工程学报(英文版)》1995,(3)
UNSTEADYFLOWANALYSISINACROSS-FLOWFANWITHACASINGUNSTEADYFLOWANALYSISINACROSS-FLOWFANWITHACASINGChenCichang(JiangsuUniversityof... 相似文献
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0 INTRODUCTIONSince the discovery of scanning tunnelingmicroscpy by G. Binnig and H. Rohrer in 1980 thisarea of research has been growing rapidly.Subsequently many different kinds of scanning probemicroscopy are invented e. g. atomic fOrce microscopy(AFM ), magnetic force microscopy (MFM ),electrostatic force microscopy(EFM) l scanning near-field optical microscopy(SNOM). Their fundamentalidea of measuring methods is the same, only theinteraction between the tip and the surface of … 相似文献
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白云飞 《机械工程与自动化》2012,(2):188-190
首先介绍了AD574A的内部结构、工作原理及工作特性,讨论了单极性和双极性输入电路的选择;然后,分别给出了AD574A与ISA总线与80C31单片机的接口技术;最后,讨论了使用AD574A时的注意事项。 相似文献
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VELOCITYANALYSISOFAPLANARMECHANISMUSING AMETHODFROMSTATICSDavidRedekopGongShouchunUniversityofOttawa,Ottawa,Ontario,CanadaKIN... 相似文献