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2018 Vol. 39, No. 1
Published: 2018-01-22
 
1 Onsite and Timely Calibration of the Large Scale Coordinate Measuring Network
ZHANG Hong-ying,YU Xiao-fen,WANG Biao
DOI: 10.3969/j.issn.1000-1158.2018.01.01
Large scale coordinate measuring network mainly composed of a plurality of measurement stations. In order to build the network in the field of measurement, and re-calibrate the measurement stations coordinates in measuring, the simulate-station calibration model is proposed following the analysis of the networks working principle and the measurement stations structure. The model takes the spherical target as the simulate-station which is arranged in a specific position. It can solve the calibration problem of the measurement network under coplanar layout. In order to obtain the distance informations required by the calibration model, two kinds of aiming methods, active scanning and center searching scanning, were proposed. The simulated calibration experiment results show that when the ranging accuracy is 0.5 mm, the mean coordinates calibration error of the measurement station was 2.1 mm. The aiming experiment results show that the standard deviations of ranging values obtained by two kinds of aiming methods were 0.16 mm and 0.34 mm. And they were roughly equal to the ranging accuray.
2018 Vol. 39 (1): 1-5 [Abstract] ( 564 ) HTML (1 KB)  PDF (1890 KB)  ( 500 )
6 A High-precision Spindle Error Separation Algorithm Based on Multi-step Process
QIAO Ling-xiao,CHEN Jiang-ning,CHEN Wen-hui,ZHANG Li,TIAN Jing-zhi
DOI: 10.3969/j.issn.1000-1158.2018.01.02
Discourse the principle of multi-step rotation error separation algorithm technique is described. The frequency domain mixing compensation error separation algorithm is proposed. By analyzing the frequency domain characteristics of spindle error, roundness error and other components of the collected data,using Fourier transform to obtain harmonic isolated eccentric of error,separate roundness error by way of culling,compensating, the spindle error is given.The algorithm can solve the problem of harmonic suppression. Collecting data using roundness instrument at the job site and giving simulation analysis,verify the feasibility of the method and choose the least squares method as evaluation method.The gap between the roundness error evaluation value of three or four,five step and the roundness error of the manufacturers (40 nm) are respectively 118 nm,113 nm,145 nm,and the evaluation value of the frequency domain compensation method is 54 nm,and the gap is only 14 nm, the separation effect of frequency domain compensation method for error is obviously better than multi-step methods.
2018 Vol. 39 (1): 6-11 [Abstract] ( 536 ) HTML (1 KB)  PDF (2489 KB)  ( 535 )
12 Research on the Method of Building Space Rectangular Coordinate System of Photoelectric Autocollimator
YANG Zhan-li,FAN Bai-xing,XI Qin,WANG Cheng-jiang,WANG Rui-peng
DOI: 10.3969/j.issn.1000-1158.2018.01.03
The aims to realize the online measurement by the combination of photoelectric autocollimator and other measurement sensors, putting forward a method of building virtual space rectangular coordinate system, establishing the space rectangular coordinate system by virtual method, deriving and verifying the parameter transformation model. It provides the theoretical basis for the joint measurement of the photoelectric autocollimator and other sensors.
2018 Vol. 39 (1): 12-14 [Abstract] ( 437 ) HTML (1 KB)  PDF (684 KB)  ( 450 )
15 Application of Hybrid Teaching-learning-based Optimization Algorithm in Spatial Straightness Evaluation
YANG Yang,LI Ming,GU Jing-jun,WANG Chen,WEI Qing-yue
DOI: 10.3969/j.issn.1000-1158.2018.01.04
In order to improve the accuracy of spatial straightness evaluation under minimum zone principle condition, a method of spatial straightness error evaluation based on teaching-learning-based optimization(TLBO) algorithm is proposed. To increases the ability of information interaction between students and local search , the population grouping strategy, shuffle strategy and local update strategy of shuffled frog leaping algorithm are used in teaching-learning-based algorithm and it is called hybrid teaching-learning-based optimization(HTLBO) algorithm. Finally, two groups of spatial straightness error examples are used by HTLBO algorithm, and the results are compared to other traditional algorithms . The results show that the HTLBO algorithm has high searching ability and fast convergence speed in the process of spatial straightness error evaluation.
2018 Vol. 39 (1): 15-19 [Abstract] ( 505 ) HTML (1 KB)  PDF (562 KB)  ( 456 )
20 Measurement Method for Contrast Sensitivity Function of the Human Eye
ZHANG Ji-yan,DONG Jin-xin,ZHOU Tao-geng,DAI Jun-cheng
DOI: 10.3969/j.issn.1000-1158.2018.01.05
According to the definition of contrast and contrast sensitivity function, a method of producing test targets for human eye contrast sensitivity measurement is proposed with integrating spheres and special light modulators. Then an automated measurement system is built and human eye contrast sensitivity function can be measured by psychophysical experiment with cross ladder method. Its spatial frequency covers 0.8, 1.5, 2.0, 3.0, 4.5, 6.0, 12.0 and 18.0 cycles per degree of visual angle. The indication error of background luminance of test targets satisfies ±5%, and contrast repeatability is 0.001 and reproducibility is 0.004, which meet requirements of human eye contrast sensitivity measurement.
2018 Vol. 39 (1): 20-23 [Abstract] ( 977 ) HTML (1 KB)  PDF (696 KB)  ( 1823 )
24 The Realization of 380~780 nm Total Spectral Radiant Flux and the Measurement Uncertainty Evaluation
ZHAO Wei-qiang,LIU Hui,LIU Jian
DOI: 10.3969/j.issn.1000-1158.2018.01.06
The basic principle of the realize 380~780 nm total spectral radiant flux (TSRF) scale is described, based on measuring total luminous flux and measuring relative spectral radiant intensity distribution by a goniospectroradiometer. The TSRF quantity traces to the primary standard of total luminous flux, and the primary standard of spectral radiant intensity, the high temperature black body. The measurement uncertainty components of TSRF scale include the total luminous flux, spectral radiant intensity standard lamp, the array spectroradiometer, the goniospectroradiometer (mechanics) and the repeatability. The expanded uncertainty is evaluated to be U=3.3%~1.6%, k=2。
2018 Vol. 39 (1): 24-27 [Abstract] ( 462 ) HTML (1 KB)  PDF (421 KB)  ( 453 )
28 An Automated System for Realizing the Triple Point of Equilibrium Hydrogen Based on Closed-cycle Refrigerator
ZHU Peng-fei,QU Ji-feng,SUN Jian-ping,CAI Jin-hui,ZHOU Zhen-yu
DOI: 10.3969/j.issn.1000-1158.2018.01.07
The TPH (triple point of equilibrium hydrogen) is one of the reference fixed points at the low-temperature rang in the international temperature scale of 1990(ITS-90) and the national primary fixed point of the temperature. In the previous primary temperature standard facility, the realization process of the TPH is time-consuming and inefficient. In order to solve these problems, a new type of realization facility of the TPH based on closed-cycle refrigerator, realized the TPH under the quasi-adabatic condition, has been developed by National Institute of Metrology of China. The program based on the Labview is used for instrument controlling and automatic measuring. The facility improves both efficiency and measurement accuracy. The results show that the repeatability of the TPH is better than 0.05 mK and the standard uncertainty is better than 0.1 mK
2018 Vol. 39 (1): 28-32 [Abstract] ( 476 ) HTML (1 KB)  PDF (1554 KB)  ( 706 )
33 Research on the Decomposition Experiment of PtO2 in Air Environment
NIU Ya-lu,SONG Kai,SUN Jian-ping,LI Xu,YE Meng
DOI: 10.3969/j.issn.1000-1158.2018.01.08
Oxidation of high purity platinum wire is one of important factors that affect the temperature measurement performance of standard platinum resistance thermometer. The main reaction product of PtO2 at different temperatures and the formation and decomposition temperature of different products are researched using differential scanning calorimetry and X-ray photoelectron spectroscopy. The results show that PtO2 will decompose into Pt and PtO gradually as the temperature rise between 550 ℃ to 820 ℃. Above 820 ℃, PtO will decompose into Pt and O2 quickly. The results will provide supports for the production and use of standard platinum resistance thermometer.
2018 Vol. 39 (1): 33-38 [Abstract] ( 479 ) HTML (1 KB)  PDF (1440 KB)  ( 609 )
39 Recent Progress on Atmospheric Greenhouse-gases LIDAR and Its Calibration
LIU Xiao-meng,LIU Qin-yong,ZHANG Liang
DOI: 10.3969/j.issn.1000-1158.2018.01.09
Atmospheric greenhouse-gas detection LIDAR is an important method for remote detection of greenhouse gases, and the LIDAR detection technology and calibration methods have become the focus research on greenhouse gas detection. The development and application of the technology and calibration method of atmospheric LIDAR for gas detection are introduced, and the prospects of atmospheric detection LIDAR in the future are described.
2018 Vol. 39 (1): 39-42 [Abstract] ( 546 ) HTML (1 KB)  PDF (1165 KB)  ( 708 )
43 Image Fusion Algorithm-based Rotating Electrodes for Electrical Capacitance Tomography
MA Min,WANG Bo-bo,YAN Chao-qi,XUE Qian
DOI: 10.3969/j.issn.1000-1158.2018.01.10
Since electrical capacitance tomography system with fixed electrodes has the drawbacks of limited measurement data and image distortion caused by the electrodes position, a novel electrical capacitance tomography model is proposed based on 16 rotating electrodes, together with a corresponding image fusion method. This model rotates a 16-electrode electrical capacitance tomography sensor four times, and the resulted measurements are used to reconstruct images by using linear back-projection and modified conjugate gradient (MCG) respectively, and thereafter wavelet transform is performed on the 5 reconstructed images, and the resulted low frequency and high frequency components are fused with the weighted average method and the principal component analysis (PCA) respectively. Experimental results show that by increasing the number of measured capacitance values and processing data with image fusion method, the proposed rotating ECT model can obviously improve the quality of reconstructed image and reduce the imaging error.
2018 Vol. 39 (1): 43-46 [Abstract] ( 492 ) HTML (1 KB)  PDF (929 KB)  ( 422 )
47 A Liquid-level Detection Method for Capillary Viscometer Based on Lagrange Parabolic Interpolation
WEN Guan-hua,TENG Zhao-sheng,LIN Hai-jun,TANG Qiu,REN Jian
DOI: 10.3969/j.issn.1000-1158.2018.01.11
In order to improve the real-time performance of the liquid-level detection for capillary viscometer and diminish the impact of concave liquid-level and sampling interval on the accuracy of the detection, a liquid-level detection method based on Lagrange parabolic interpolation is proposed. Fiber optic sensors are used as liquid-level detection components. Firstly, the first order difference of the sampling data is figured out. Then Lagrange parabolic interpolation is operated on the sampling data’s first order difference of the sampling time with the least first order difference and its adjacent sampling time. Finally, the timing point is worked out with the time derivative of the interpolation polynomial and the automatic liquid-level detection at the two timing positions is accomplished. Compared with the existing method based on least squares linear fitting, the proposed method has better real-time performance for the less calculation and is less impacted by the sampling interval. Experiments show that the repetitiveness of kinematic viscosity measured with the method is less than 0.1%.
2018 Vol. 39 (1): 47-51 [Abstract] ( 494 ) HTML (1 KB)  PDF (335 KB)  ( 451 )
52 Design of a Three Dimensional Force Sensor
ZHANG Qiang,SONG Ai-guo,Liu Yu-qing,JIANG Guo-hua,ZHOU Bo-he
DOI: 10.3969/j.issn.1000-1158.2018.01.12
A three dimensional force sensor is designed for simulating the humanoid dexterous hand. Using the structure of the combination of the cross beam and the central straight beam to achieve perception of three-dimensional force, using ANSYS tool for the design of cross beam elastic body statics is analyzed, optimized through the analysis of the structure size of elastomer, and give the optimal placement scheme. The static calibration experiment was conducted on the designedthree-dimensionalfingertip force sensor, andestablished the dimension coupling error model, using the static decoupling algorithm to decouple the error of sensor, effectively improve measurement precisionof the fingertip threedimensional force sensor. The experimental resultsmake knowthat the measurement precision of the designed three-dimensional fingertip force sensor is better than 2.5%.
2018 Vol. 39 (1): 52-55 [Abstract] ( 720 ) HTML (1 KB)  PDF (725 KB)  ( 748 )
56 Compensative Vibration Model of Roll System Based on Horizontal Vibration of Rolled Piece
LIU Bin,JIANG Jia-hao,LIU Fei,LIU Hao-ran,LI Peng
DOI: 10.3969/j.issn.1000-1158.2018.01.13
Considering the influence to the dynamic characteristics of rolling force and rolling friction from horizontal vibration of rolled piece, a compensative vibration model of roll system is established. According to the Lagrange principle of generalized dissipation, dynamic equilibrium equation is established respectively both in rolling direction and in vertical direction. With four-high strip mill of a factor as an example, simulating and analyzing the horizontal vibration velocity of rolled piece and the vibration displacement of roll under different rolling speeds. Five sets of rolling force data at different rolling speeds are obtained. Finally, the theoretical values of rolling force and the test data are compared with the model before and after optimization. Research results show that: the calculated values of the rolling force after optimization are far more close to the actual working condition;
2018 Vol. 39 (1): 56-60 [Abstract] ( 719 ) HTML (1 KB)  PDF (359 KB)  ( 453 )
61 Fault Diagnosis of Wind Turbine Gearbox Bearing Based on Fractal Dimension and GA-SVM
SHI Pei-ming,LIANG Kai,ZHAO Na,AN Shu-jun
DOI: 10.3969/j.issn.1000-1158.2018.01.14
For wind turbine gearbox bearing fault diagnosis is studied, and a fault diagnosis method based on the fractal dimension and genetic algorithm support vector machine (GA-SVM) is put forward. Based on the commonly used time domain feature parameters as the support vector machine identification parameters, the fractal dimension feature parameters are introduced to enhance the recognition accuracy of support vector machines. The model of support vector machine parameters optimization based on genetic algorithm is proposed, and the optimal support vector machine parameters are obtained by the optimization of GA. Using the gear box bearing data from a wind farm in Zhangjiakou, Hebei province for fault diagnosis. Experimental results show that the proposed model GA-SVM provided a good solution to the parameter selection problem, as well as the characteristic parameters based on fractal dimension also improve the recognition accuracy of wind turbine bearing failure.
2018 Vol. 39 (1): 61-65 [Abstract] ( 499 ) HTML (1 KB)  PDF (1544 KB)  ( 610 )
66 Analyses of Measurement Errors of Shear Bands with Constant Strains Based on the One-and Two-order DIC Methods
DU Ya-zhi,WANG Xue-bin,DONG Wei,FENG Wei-wu,HOU Wen-teng
DOI: 10.3969/j.issn.1000-1158.2018.01.15
The horizontal and oblique shear band with constant strains are produced, using the digital image correlation (DIC) method, the displacement field and strain field of the inside and outside the shear band were measured, the influences of the shape function, subset size and spacing of points on displacement were analyzed. The results showed that the displacement error limits of the one-or two-order DIC methods are high nearby the boundary of a shear band, because a subset covers a part of a shear band. The larger the subset size is or the shorter the distance from the subset center to the boundary of a shear band is, the higher the displacement error limit is. Usually, the displacement error limits of the two-order DIC method are much lower than those of the one-order DIC method nearby the boundary of a shear band. With the increase of the spacing of points, the shear strain-coordinate curves of the shear band in the normal direction of one- or two-order DIC methods change from steep to gentle, and widths of shear bands increase.
2018 Vol. 39 (1): 66-71 [Abstract] ( 459 ) HTML (1 KB)  PDF (2698 KB)  ( 521 )
72 Application of Ultrasonic Method in Contact Stress Testing of Electric Connector
LUO Yan-yan,FENG Yu-zhu,HAO Liang,LIU Xin-hao,LIU Shuo
DOI: 10.3969/j.issn.1000-1158.2018.01.16
The reliable contact of the electric connector is achieved through the stable contact pressure between the contacts. Based on the transmission characteristics of ultrasonic wave, a nondestructive testing method for contact pressure is proposed, which is suitable for the contacts with closely inserting structure characteristic. The testing circuit is designed and tested. Analyzing the contact pressure of the electric connector. The test results show that the contact pressure of electrical connector in different types is related to the structure parameters of the contact, and with the decrease of the diameter of the hole, the contact pressure is reduced; but the contact pressure of the electrical connector of the same type also has a certain dispersion. This dispersion may be one of the potential dangers of contact failure.
2018 Vol. 39 (1): 72-76 [Abstract] ( 532 ) HTML (1 KB)  PDF (561 KB)  ( 421 )
77 Optimization and Application of Weighted One-rank Local Chaos Prediction Model Based on Multi-variable
ZHANG Shu-qing,LIU Zi-yue,HE Hong-yun,REN Shuang,ZHANG Li-guo,JIANG Wan-lu
DOI: 10.3969/j.issn.1000-1158.2018.01.17
In view of the influence of multi-variable on the chaotic prediction in practical application, a method for phase space reconstruction of multivariate time series is proposed, and a weighted one-rank local chaos forecasting model on multi-variable was established. The equal probability-based maximum joint entropy and the minimum Shannon entropy are introduced to get the delay time and the embedding dimension respectively, realizing the sub-sequence reconstruction to the chaotic prediction model. The nearest neighbor point method is used to determine the neighborhood of the prediction center to avoid false neighbors, and the correlation analysis is used to determine the observed variables. The model was applied to short-term load forecasting, and the temperature time series was introduced as another observation variable by the analysis of the impact of temperature and other factors related to electric load. The experimental results showed that the prediction accuracy was improved compared with the single variable forecasting method.
2018 Vol. 39 (1): 77-82 [Abstract] ( 462 ) HTML (1 KB)  PDF (1486 KB)  ( 648 )
83 Research on Measuring Leakage Current ofDC High-voltage Resistive Divider
ZHANG Huang-hui,LIN Fei-peng,SHAO Hai-ming,ZHANG Zhong-hua
DOI: 10.3969/j.issn.1000-1158.2018.01.18
A device using to measure the leakage current of DC high voltage resistor divider is introduced. The device uses ZigBee wireless communication technology, which by way of an independent power supply to avoid the risk of high voltage electric field resulting in damage to the measuring instrument, and solve issues of difficult to measure the leakage current of the voltage divider in the high voltage state. It can overcome the effect of high voltage power supply ripple and drift by using synchronous sampling method, and the uncertainty of measurement is less than 9.8×10-6 V, k=2.
2018 Vol. 39 (1): 83-88 [Abstract] ( 509 ) HTML (1 KB)  PDF (1593 KB)  ( 501 )
89 Research of Wind Turbine Main Bearing Condition Monitoring Based on Correlation PCA and ELM
HE Qun,WANG Hong,JIANG Guo-qian,XIE Ping,LI Ji-meng,WANG Teng-chao
DOI: 10.3969/j.issn.1000-1158.2018.01.19
A condition monitoring method of main bearing based on correlation coefficient method, principal component analysis and extreme learning machine are proposed. First, correlation coefficient method is used to select the initial input variables which is related to the main bearing temperature in the supervisory control and data acquistion system. Further, to eliminate the correlation and the redundancy between the selected variables, principal component analysis is applied to reduce the dimension. Again, the extreme learning machine is used to construct the normal behavior model of the main bearing temperature and predict the temperature. Last, a moving window and kernel density estimation method is used to analyze the residual, and based on the measured data to simulate main bearing fault conditions. The experimental results demonstrate that the proposed method can effectively achieve the potential failure prediction and avoid serious fault of the main bearing.
2018 Vol. 39 (1): 89-93 [Abstract] ( 785 ) HTML (1 KB)  PDF (585 KB)  ( 734 )
94 A Novel Digitizing Measurement Method for Large Trigger Delay of Digital Oscilloscopes
LIANG Zhi-guo
DOI: 10.3969/j.issn.1000-1158.2018.01.20
Aiming at the large trigger delay of digital oscilloscope, a novel digitizing measurement method is presented. By using the period of sinusoidal as standard, the large trigger delay is divided into two parts, one part is just consist of many periods of sine wave, another part include the partial period of sine wave. The partial period part can be measured through phase difference method, and to the integer periods part, first, one can divided the large trigger delay into many smaller trigger delay increment, through measuring each smaller trigger delay increment directly, then the cumulative results is gotten. Its the rude result of large trigger delay that can be used to calculate the integer. Finally, through composing of the two parts, the large trigger delay is gotten. The correctness and feasibility are proved by some experiments on digital oscilloscope, the method can be used to the measurement and calibration of large trigger delay of digital oscilloscopes.
2018 Vol. 39 (1): 94-98 [Abstract] ( 448 ) HTML (1 KB)  PDF (490 KB)  ( 608 )
99 Research on Calculating Method about the Standard Value of Noise for Passive Device
WU Ai-hua,LIU Chen,WANG Yi-bang,LIANG Fa-guo
DOI: 10.3969/j.issn.1000-1158.2018.01.21
Noise standard value calculation method is studied,which is in urgent need of vector network with noise option calibration process. The meaning of the noise standard value of the passive components and the characteristics of the existing calculation methods are reported, and through the existing two methods and different temperature conditions of the test data, the relationship between noise standard value and the ambient temperature and the S parameters of passive components is compared and analyzed. Based on the noise model of passive components, a new vector calculation method is proposed, which includes the temperature parameters. At 290 K ambient temperature, the maximum deviation of the calculated results in the 10-4~10-5 order of magnitude, which were calculated by the new method and the commercial software. The accuracy of the standard value of noise figure increased by about 0.08dB at 297 K ambient temperature, at the same time, the experimental results show that the ambient temperature has little influence on the amplitude and phase of the optimal source reflection figure.
2018 Vol. 39 (1): 99-103 [Abstract] ( 495 ) HTML (1 KB)  PDF (1119 KB)  ( 491 )
104 The Impedance Mismatch Correction for Antenna Gain Extrapolation Measurement and Its Uncertainty Evaluation
CHEN Jun,SONG Zhen-fei,WAN Fa-yu,XIE Ming
DOI: 10.3969/j.issn.1000-1158.2018.01.22
A full-port impedance mismatch model based on signal flow analysis and the corresponding mismatch correction formula for antenna gain is developed, and the impedance mismatch correction value can be obtained by using measured scattering parameters at each port. The impedance mismatch correction uncertainty and its probability distribution evaluation using Monte Carlo method is proposed. This work provides an effective method for scientific and systematic evaluation of extrapolation gain measurement uncertainty.
2018 Vol. 39 (1): 104-108 [Abstract] ( 511 ) HTML (1 KB)  PDF (804 KB)  ( 458 )
109 Calibration Methods of Neutron Ambient Dose Equivalent Meters and APMP Comparison
ZHANG Hui,ZHANG Yan-li,XIA Xuan
DOI: 10.3969/j.issn.1000-1158.2018.01.23
Neutron ambient dose equivalent (rate) meters must be calibrated accurately in proper methods as the main instruments for monitoring of neutron radiation level. A comparison for the calibration of ambient dose equivalent meters in ISO neutron reference fields (APMP.RI(III)-S1) was hold in 2012 to support the calibrating capability declared by the member of Asia Pacific Metrology Programme. The neutron radiation field based on the radionuclide neutron sources were recommended to calibrate the instruments provided by the pilot laboratory and shadow cone method and distance variation methods were required for correction of the scatter neutrons. The calibrated factor with uncertainty should be reported by the laboratory took part in the comparison. National Institute of Metrology(NIM) took part in the comparison. The calibration results submitted by the labs took part in the comparison are consistent with each other.
2018 Vol. 39 (1): 109-114 [Abstract] ( 506 ) HTML (1 KB)  PDF (454 KB)  ( 501 )
115 Application of Hydrocarbon Dew Point Analysis in Preparation for Calibration Natural Gas
DENG Fan-feng,ZHOU Xin,DONG Liao-yu,LI Zhi-ang,ZHENG Li-wen,FANG Zheng
DOI: 10.3969/j.issn.1000-1158.2018.01.24
Natural gas phase equilibrium diagram was drawn through analysis and simulated calculation of hydrocarbon dew point based on Peng-Robinson property equation. Compared to the saturated vapor pressure estimation suggested by GB/T 5274—2008, hydrocarbon dew point analysis of the phase could predict the liquefaction possibility accurately at certain pressure and temperature then to ensure the reliability of the standard gas mixture preparation values.
2018 Vol. 39 (1): 115-118 [Abstract] ( 514 ) HTML (1 KB)  PDF (1038 KB)  ( 451 )
119 Uncertainty Evaluation for the Determination of the Retention Ratio of the Ultrafiltration Membrane by PEG-20000
WANG Xu-liang,LI Zong-yu,ZHANG Yan-ping,HAO Jun,PAN Xian-hui
DOI: 10.3969/j.issn.1000-1158.2018.01.25
Molecular weight cut off and retention are two technical parameters of ultrafiltration membrane performance. Choosing PEG-20000 as a standard substance, establishing evaluation mathematical model of uncertainty of retention test results to analyze the sources of uncertainty, the retention test results were evaluated. The results indicates that the polydispersity coefficient(Mw/Mn)of PEG-20000 is 1.005, which is better than the standard test for molecular weight cut-off standard material distribution coefficient less than the requirements of 1.8 and GPC spectrum showed a single peak form, in line with PEG clear structure, molecular weight distribution narrow features, which fully meet the testing needs. There is a good linear relation between ABS and concentration in the standard curve and the correlation coefficient R2 is over 0.999. The retention ratio of the ultrafiltration membrane by PEG-20000 is 93.04%, through repeated experiment. The results were evaluated type A and type B uncertainty. It showed that expanded uncertainty is 2.90% when coverage factor is k=2 and level of confidence is 95%.
2018 Vol. 39 (1): 119-124 [Abstract] ( 538 ) HTML (1 KB)  PDF (509 KB)  ( 540 )
125 Optimize NOx Emissions Model of Boiler Based on Chaos Group Teaching-learning-based Optimization Algorithm
MA Yun-peng,NIU Pei-feng,CHEN Ke,YAN Shan-shan,LI Guo-qiang
DOI: 10.3969/j.issn.1000-1158.2018.01.26
In order to balance the global and local search ability of the teaching-learning-based optimization, an enhanced teaching-learning-based optimization algorithm is proposed. The proposed algorithm adopts three major adjustment mechanisms. First, the chaos method is applied to initialize population. Second, a self-adaptive inertia weight is adopted to update the individual in teaching phase. Finally, in learning phase, the idea of shuffled leap frog algorithm is applied to group the individuals for updating the worst solution. Ten famous testing functions are applied to test the performance of the proposed algorithm, comparing with ABC, GSA and conventional TLBO. The experiment results show that the improved algorithm own better global and local search ability and high convergence precision. Simultaneously, the proposed algorithm is used to optimize the NOx emissions model of circulating fluidized bed boiler, the experiment result shows that the proposed algorithm possesse better identification ability and generalization, and it also can guide the practical project.
2018 Vol. 39 (1): 125-129 [Abstract] ( 483 ) HTML (1 KB)  PDF (814 KB)  ( 407 )
130 Research on the Variation of Matrix Effect in the Verification of Electrolyte Analyzer
CUI Hong-en,YAO Shao-wei,FENG Zhi-ming,ZHANG Chao
DOI: 10.3969/j.issn.1000-1158.2018.01.27
To observe the variation of matrix effect during the metrological verification of the electrolyte analyzer, the electrolyte analyzer using the calibration solution of the aqueous solution matrix, and the biochemical analyzer using the calibration solution of the human serum matrix was calibrated, and then the standard materials of aqueous solution matrixes and human serum matrixes with different concentrations was respectively determined, the significance of the verification results will be analyzed.The test results of K+, Na+, and Cl- are statistically significant (p<0.01) within certain concentration ranges after the calibration of the biochemical analyzer using human serum matrix and electrolyte analyzer using the aqueous solution matrix.Therefore, the deviation caused by the matrix effect varies with the concentration during the calibration process.
2018 Vol. 39 (1): 130-134 [Abstract] ( 539 ) HTML (1 KB)  PDF (963 KB)  ( 395 )
135 Comparative Analysis of Uncertainty Measurement Evaluation with GUM and MCM
LIU Yuan-yuan,YANG Jian,ZHAO Xi-yong,ZHAO Shi-wei
DOI: 10.3969/j.issn.1000-1158.2018.01.28
Take the evaluation of measurement uncertainty of wind speed in the field of meteorology calibration as an example, in the conditions of the normal distribution and other distributions of input quantities,results of simplified wind speed model with GUM and MCM are comparative analysed,and the uncertainty of water vapor which is neglected in the simplified model is quantified.The results indicate that MCM can be used in a larger scale,especially for complicated models.Due to the omitted derivation process and the uncertainty calculation of all the factors,evaluation results of uncertainty in measurement with MCM are more reasonable and operable.
2018 Vol. 39 (1): 135-139 [Abstract] ( 774 ) HTML (1 KB)  PDF (779 KB)  ( 1250 )
140 Analysis of Measurement Message Fusion and Uncertainty Treatment Based on Possibility Theory
YU Xue-feng,YU Jie,ZHANG Hong-qing
DOI: 10.3969/j.issn.1000-1158.2018.01.29
Deal with the question of measurement message fusion and uncertainty treatment, a method using conditional possibility distribution to derive the posteriori information about the measurement was proposed. An approach to measurement message fusion and uncertainty treatment in terms of random-fuzzy variables (RFVs) possibility distributions instead of probability distributions was presented. A simple measurement example was also considered to prove the usefulness and effectiveness of the proposed method. The results show that, based on possibility theory, it is possible to obtain a more accurate posteriori estimate of the measurement combining with the reliable measurement priori knowledge.
2018 Vol. 39 (1): 140-144 [Abstract] ( 512 ) HTML (1 KB)  PDF (661 KB)  ( 455 )
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