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2011 Vol. 32, No. 5
Published: 2011-09-22
 
385 Autonomous Algorithm for Relative Error of Smart Electric Energy Meter Cluster
GUO Jing-tao,ZHANG Ren,JIN Zhi-gang
DOI: 10.3969/j.issn.1000-1158.2011.05.01
A tree topology electric energy meter cluster is demonstrated, giving the premise of energy conservation, providing any meter relative error, all the other meters relative errors can be accomplished according to a group of meter readings.This method for meter relative error requires no extra standard instrument.A virtual branch and a virtual load are introduced to present meter power consumption, leaked current power consumption and line resistor consumption.According to law of energy conservation, the problem is transformed to solving a linear or quadratic equation group and numeric method is employed.This algorithm needs the aid of data base with historical readings.Remote automatic reading function of smart meter makes the algorithm applicable.And the algorithm can reduce the cost for maintaining of the meters and help to determine the meters serving time scientifically.The experiment shows that the range of result error is about 0.6%.
2011 Vol. 32 (5): 385-392 [Abstract] ( 558 ) HTML (1 KB)  PDF (831 KB)  ( 558 )
392 A New Simplified Approach to Spectrum Analysis for Digital-to-Analog Converters and Its Fundamental Measurement Without a Filter
LU Zu-liang,HUANG Lu,YANG Yan,WANG Lei,Eddy So
DOI: 10.3969/j.issn.1000-1158.2011.05.02
A new simplified approach to the spectrum analysis of digitally synthesized sine-waves generated by DACs is described,including amplitude and phase. The analysis is based on the perfect wave produced by the DAC according to the discrete digital values of a sinusoidal signal. The fundamental component of this wave has an approximate relative difference of -1. 644 9/n2 in amplitude and a phase shift of -p/n with respect to the ideal original sinusoidal waveform signal,where n expresses the number of samples per period. In addition,there are the harmonic components of the(tn±1)th order having an amplitude of 1/(tn±1)times the amplitude of the fundamental component(t=1,2,… ). Based on this knowledge,an experiment to compare only the fundamental component without filter is described,and some applications are discussed.
2011 Vol. 32 (5): 392-399 [Abstract] ( 685 ) HTML (1 KB)  PDF (728 KB)  ( 486 )
400 A Novel Algorithm for Harmonic Measurement Based on Multiple-average
XUE Jin-hui,YU Hai-bo,BAI Jing-fen,LU Zu-liang
DOI: 10.3969/j.issn.1000-1158.2011.05.03
Based on the fundamental principle of multiple-average harmonic analysis, a novel algorithm for harmonic measurement is proposed, with which the amplitude and phase of the harmonics can be calculated accurately and conveniently. Its accuracy has been verified by computer simulation and physical experiment described. Further, the influence of noise at samples to the result has been discussed by Monte Carlo method and a qualitative result for practical engineering application is given.
2011 Vol. 32 (5): 400-406 [Abstract] ( 440 ) HTML (1 KB)  PDF (529 KB)  ( 492 )
407 Progress in the Resistance and Capacitance Bridge
LAN Jiang,ZHAO Jian-ting,ZHANG Zhong-hua,LU Zu-liang,LI Zheng-kun
DOI: 10.3969/j.issn.1000-1158.2011.05.04
The goal of the resistance and capacitance bridge is to compare resistance with capacitance. To review the important role played by the resistance and capacitance bridge in the entire field of electrical measurement, and then a detailed analysis of the traditional resistance and capacitance bridge about the basic principles and international profile in research is demonstrated, and finally in-depth analysis about some inherent shortcomings in these bridges is pointed out in the first time, and at the same time several new research programs are put forward.
2011 Vol. 32 (5): 407-412 [Abstract] ( 440 ) HTML (1 KB)  PDF (1145 KB)  ( 678 )
413 The Dynamic Error Modeling Study of CMM Touch Trigger Probe Based on RBF Neural Network
QU Ying,LUO Zai,LU Yi,GUO Bin
DOI: 10.3969/j.issn.1000-1158.2011.05.05
To solve the problem of low precision when touch trigger probe of CMM is in the process of dynamic measurement, the sources of the dynamic error for the probe were analyzed. Through the measurement experiment to the standard ball, the main factors which influence the dynamic error of probe were verified. Among them there are three most important crucial factors: approach speed, stylus length and stylus tip diameter. To reduce the dynamic measurement error caused by the probe, the compensation model of RBF neural network was introduced. It can avoid the derivation of complicated mathematical relationships in the traditional error compensation model. On the Global Class 9158 CMM, the standard ball was measured and the network training data was obtained. The standard ring gauge was measured as the test sample and it was compensated by the error model. The experiment results show that after the compensation by the model the mean measurement error decreases from 3.5 μm to 1.3 μm, and the model is stable and reliable.
2011 Vol. 32 (5): 413-418 [Abstract] ( 464 ) HTML (1 KB)  PDF (431 KB)  ( 623 )
419 New Measurement of Omnipotence Tool-Microscope Based on Image Processing
WANG Bo,NIU Sai-sai
DOI: 10.3969/j.issn.1000-1158.2011.05.06
Based on the analysis of the advantages and disadvantages of the traditional omnipotence tool-microscope and modern digital equipment,a new measurement based on image processing is presented.This method combines image measurement technology with grating measurement technology based on FPGA and SCM,and uses AutoCAD secondary development of technology for length,angle,diameter,and other geometric precision measurement of the amount.On the basis of maintained advantages of original equipment such as high precision,strong anti-jamming,long-term stability,wide application and so on,it can improve efficiency and precision of measurement and reduces operation intensity.Compared with the test results of Dual-frequency laser interferometer,it proves that this method has high precision repeatability and measurement accuracy.
2011 Vol. 32 (5): 419-423 [Abstract] ( 620 ) HTML (1 KB)  PDF (456 KB)  ( 754 )
424 Research on the 3D Polar Coordinate Measurement
YUAN Dao-cheng,YANG Wei-chuan,LI Yun-fei,JIANG Jia-dong
DOI: 10.3969/j.issn.1000-1158.2011.05.07
A prototype of 3D polar coordinate measuring machine （3D PCMM）is developed to measure locations of bores distributed on spherical surfaces.3D PCMM solved the problem that how to measure the blind areas of the spherical surface with optical probes.Characters of 3D PCMM technique are analyzed,such as measurement principle,work piece coordinate construction,probe application,temperature characteristic,error transmission etc.The results indicate that the method of 3D polar coordinate measurement is suitable for non-contact optical probe application and in favor of precision improvement of 3D coordinate measurement.
2011 Vol. 32 (5): 424-426 [Abstract] ( 585 ) HTML (1 KB)  PDF (439 KB)  ( 800 )
427 Study on Online Measurement Technology for Large Cylindrical Shell Section Forgings Outer Diameter in Hot State
ZHANG Yu-cun,FU Xian-bin,QI Yan-de,Yang Sha-sha
DOI: 10.3969/j.issn.1000-1158.2011.05.08
In order to on-line measure the outer diameter of large cylindrical shell section forgings,a new measurement method is proposed.First,the distance between the scanner and the surface of forging is got through scanning the surface of forging by the laser scanner.Then the distance information is transformed into coordinate information,which is processed by using data registration and curve reconstruction.Finally the contour curve of forgings is showed,thereby the size of forgings is measured.The online measurement of large cylindrical shell section forgings is achieved.This method is verified feasibility by the Matlab simulation.
2011 Vol. 32 (5): 427-431 [Abstract] ( 567 ) HTML (1 KB)  PDF (500 KB)  ( 420 )
432 Analysis of Spectral Mismatch's Impact on Solar Cell Calibration
SUN Hao,XIONG Li-min
DOI: 10.3969/j.issn.1000-1158.2011.05.09
Standard solar cell short circuit current can be used to determine the total irradiance intensity of the solar simulator. Four common types of solar cells were selected: monocrystalline,polycrystalline,a-Si thin film and dye-sensitized solar cell and the spctral response was measured. The spectral irradiance distribution of the solar simulators of class A,B and C on spectral match aspect was measured respectively. According to spectral mismatch calculation formula,combined with standard AM1.5G solar spectral irradiance distribution data, the spectral mismatch factor among light sources spectrum and cell spectral response was calculated, and the impact on solar cells calibration was analyzed.
2011 Vol. 32 (5): 432-435 [Abstract] ( 932 ) HTML (1 KB)  PDF (367 KB)  ( 1598 )
436 Study on the Reconstruction Algorithms of ERT
YU Jin-hua
DOI: 10.3969/j.issn.1000-1158.2011.05.10
The electrical resistance tomography reconstruction algorithms of two-phase flow can be categorized into two kinds,direct algorithms and iterative algorithms.These reconstruction algorithms are compared and studied,the results show that:the direct algorithms are fast,but the reconstruction images are blurry and can only be used as qualitative analysis.The iterative algorithms are slower,but the reconstruction images quality is better. As the pixels rise to enhance resolution of reconstruction images,the increment time of the direct algorithms is very small.The reconstruction time of the Newton-Raphson algorithm and BFGS algorithm is largely increased because of the increased dimension of the Hessian matrix.The Hessian matrix and its inverse matrix are simplified in the modified BFGS algorithm,therefore the reconstruction time is increased a little.
2011 Vol. 32 (5): 436-440 [Abstract] ( 617 ) HTML (1 KB)  PDF (441 KB)  ( 632 )
441 The Effective Area and Distortion Coefficient of CCM. P-K13 Transfer Standard and the Analysis of Uncertainty
YANG Yuan-chao,YUE Jin,LI Yan-hua
DOI: 10.3969/j.issn.1000-1158.2011.05.11
The international key comparison of CCM.P-K13 for 500 MPa range of hydraulic gauge pressure is described, and a piston pressure gauge with 2 mm2 nominal effective area used as a transfer standard is studied. The effective area of the transfer standard is determined at 10 different pressure points through cross-float equilibrium experiments. The effective areas at different pressures have nonuniform uncertainties and correlations with each other. The zero-pressure effective area and pressure distortion coefficient are calculated using generalized least square (GLS) method with heteroscedasticity and correlation being considered,and their uncertainties are analyzed.
2011 Vol. 32 (5): 441-445 [Abstract] ( 451 ) HTML (1 KB)  PDF (441 KB)  ( 357 )
446 Study on Measurement Methods for Vertical Tank Floating Roof and Bottom
TONG Shi-zhong,XIE Zhi,YIN Wei-wei,YU Long-wen,FU Gui-zeng
DOI: 10.3969/j.issn.1000-1158.2011.05.12
The factors influencing measuring accuracy for vertical metal tank floating roof and the tank bottom are introduced. In order to solve these problems, new methods that on the basis of pressure transmitter floating roof mass and on the basis of the putting-into-type level meter measuring bottom capacity are described. The feasibility of these methods are tested through qualitative analysis of the simulation experimental results. Finally, the real-time measurement system is set up.
2011 Vol. 32 (5): 446-449 [Abstract] ( 437 ) HTML (1 KB)  PDF (327 KB)  ( 470 )
450 Research on Measurement Standards and Establishment of Traceable Hierarchy of Micro-nano Force Metrology
Hu Gang
DOI: 10.3969/j.issn.1000-1158.2011.05.13
The research of force metrology in the range from nanonewton to micronewton is an important orientation in international metrological researches at present. Up-to-date research achievements of the force standards, force sensors, reference cantilevers and traceable approaches in the range from nanonewton to micronewton in NIST, NPL, PTB and KRISS are described. A traceable hierarchy of micro-nano scale force metrology is put forward. It guarantees accuracy and consistency of dissemination for micro-nano mechanical properties testing in the field of advanced materials, biotechnology, microelectronics and etc.
2011 Vol. 32 (5): 450-454 [Abstract] ( 593 ) HTML (1 KB)  PDF (354 KB)  ( 970 )
455 Duct Perturbations to the Radial Modes of Cylindrical Resonators
ZHANG Fang,ZHAN Ke-tao,FENG Xiao-juan,LIN Hong,ZHANG Jin-tao
DOI: 10.3969/j.issn.1000-1158.2011.05.14
Correcting the effect of the fill duct for gas-in and out is very necessary for Boltzmann constant kB measurement. The duct perturbations for ideal radial resonance modes of the cylindrical acoustic resonator were studied, and the various acoustic impedances of duct due to different ways of connection at the end of the duct were analyzed,The perturbations for the resonance frequency and the half width were calculated to be Δf/f0≈-0.04×10-6 and Δg/f0≈14.15×10-6 respectively. The influences for perturbations of the ideal radial resonance modes due to the changes of length, internal diameter and fixed-position of duct were also analyzed.
2011 Vol. 32 (5): 455-458 [Abstract] ( 402 ) HTML (1 KB)  PDF (674 KB)  ( 644 )
459 A Method of the Fast Edge Signal Generation for Oscilloscope Calibration
FU Zai-ming,WANG Hou-jun,HUANG Jian-guo
DOI: 10.3969/j.issn.1000-1158.2011.05.15
A new method of fast edge generation based on step-recovery diode circuits is developed.A few schottky barrier diodes are used to segregate the DC offset circuit from the pulse source and the loader.The inductance is placed in the DC offset circuit to shield the RF signal,and a resistance is added to absorb the signal reflection from the rearward to optimize the fast edge waveform.The standardization of the fast edge signal is depended on the veracity of the offset current and the amplitude of the input pulse. At last a fast edge circuit for the calibration of 1GHz bandwidth oscilloscope is designed and achieves a fast edge with 80ps rise time,by which the feasibility of the new method is proved.
2011 Vol. 32 (5): 459-462 [Abstract] ( 525 ) HTML (1 KB)  PDF (764 KB)  ( 707 )
463 A Method for Correcting the Error of Adapters during Noise Source Measurement
LIANG Wei-Jun,GAO Qiu-Lai
DOI: 10.3969/j.issn.1000-1158.2011.05.16
Y factor method is adopted to measure the efficiency of the adapters,and the effect of the method on the uncertainty of the noise power measurement is analyzed.A gas discharge noise source with waveguide connect is calibrated by the coaxial noise measurement system and the measurement uncertainty of the excess noise ratio is enlarged a little from 0.20 dB to 0.23 dB caused by using a waveguide-coaxial adapter.The results of the measurement show that the method is simple and efficient.
2011 Vol. 32 (5): 463-465 [Abstract] ( 450 ) HTML (1 KB)  PDF (364 KB)  ( 451 )
466 The Design of Frequency-drift Insensitive Terahertz Transmission Measurement System
MA Wu-xi,LIU Jian-jun,WANG Wei,LI Jing,HONG Zhi
DOI: 10.3969/j.issn.1000-1158.2011.05.17
The precision of the conventional terahertz transmission measurement system with a parallel-plate sample will be reduced due to the interference effect, when the frequency of the THz source drifts. To resolve the problem, a frequency-drift insensitive transmission measurement system composed of double-path is proposed. A F-P interference model is built with MATLAB. The parameters are optimized, and the effects of the terahertz source frequency drift on the precision of both the single-and double-path transmission measurement are analyzed and compared. The results demonstrated that such kind of measurement system could avoid the influence of the frequence-drift of the THz source, thus improving the measurement accuracy.
2011 Vol. 32 (5): 466-469 [Abstract] ( 490 ) HTML (1 KB)  PDF (1252 KB)  ( 397 )
470 The Application of Neighbor Comparing Digital Filter and Wavelet Transform in EEG De-noising
LUO Zhi-zhen,QIU Zhi-bin
DOI: 10.3969/j.issn.1000-1158.2011.05.18
An EEG de-noising method which combines neighborhood comparison and wavelet transform is described and it was used to de-noising the EEG signals which contains pulse jamming. First, the algorithm of neighborhood comparison filtering and the de-noising principle of wavelet transform was introduced. Then 10 EEG signals was processed by the de-noising method. Finally, the de-noising effects and wavelet transform de-noising effects were compared. Experimental results show that both signal noise ratio and root mean square error, combining de-noising effects of the two methods were superior to the de-noising effects of wavelet transform.
2011 Vol. 32 (5): 470-473 [Abstract] ( 526 ) HTML (1 KB)  PDF (1132 KB)  ( 422 )
474 he Sample Preparation Method for the Determination of Si Isotopic Abundances Ratios using Gas-source Mass-spectrometry
LI Hong,YI Hong,ZHANG Jing-chang,YI Wei
DOI: 10.3969/j.issn.1000-1158.2011.05.19
The development of sample preparation for the determination of Si isotopic abundances ratios with gas-source mass-spectrometry is introduced.The single crystal silicon is converted to SiO2 based on alkaline solution digestion followed by cation-exchange column and calcinating at 850 ℃.After dissolving SiO2 with HF acid, H2SiF6 solution is obtained .BaSiF6 precipitation is formed by drop adding BaCl2 solution.Then BaSiF6 is decomposed to SiF4 and Si isotope ratios is measured by gas-source mass-spectrometry.By Optimizing the sample preparation procedure,high recovery SiF4 gas is obtained.The results indicate that the sample preparation method for the determination of Si isotopic abundances ratios has high repeatability and recovery, meeting the requirement for the accurate measurement of silicon molar mass.
2011 Vol. 32 (5): 474-477 [Abstract] ( 511 ) HTML (1 KB)  PDF (392 KB)  ( 494 )
478 General Principle for Uncertainty Evaluation of Enzyme Activity Measurement
WU Li-qing,YANG Bin,WANG Jing
DOI: 10.3969/j.issn.1000-1158.2011.05.20
The general principle for uncertainty evaluation of enzyme activity measurement is presented based on previous experiment.Totally five steps toward the uncertainty evaluation of enzyme activity measurement are introduced, including the principle of experimental condition selection and optimization, uncertainty source analysis, uncertainty component and combination graph drawing, sensitivity factor and uncertainty component calculation, standard combination uncertainty and expanded uncertainty calculation.The principle presented will lay a foundation for the accuracy and validity in the enzyme activity measurement and enzyme activity certified reference material production.
2011 Vol. 32 (5): 478-480 [Abstract] ( 543 ) HTML (1 KB)  PDF (298 KB)  ( 344 )
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