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2017 Vol. 38, No. 2
Published: 2017-03-22
 
129 Development of H500 Type High Precision Vacuum Blackbody Used as a Calibration Standard for Infrared Remote Sensing
GONG Lü-yu,HAO Xiao-peng,SUN Jian-ping,SONG Jian,YUAN Zun-dong,GU Ming-jian,DING Lei
DOI: 10.3969/j.issn.1000-1158.2017.02.01
A high precision vacuum blackbody（H500 type）with the temperature range between -93 ℃ to 220 ℃ is developed at the National Institute Metrology of China. The performances are tested under the vacuum and low background condition (liquid-nitrogen-cooled shroud). The major technical parameters of the blackbody, such as the emissivity and uniformity are measured at room temperature and atmospheric environment. When the heating rate is 1 ℃/min, the time is shorter than 50 minutes and the temperature stability is better than 0.01 ℃ during 10 minutes. The emissivity of the blackbody at 20 ℃, 30 ℃ and 50 ℃ are 0.996 5, 0.9966 and 0.996 3, respectively. The temperature uniformity at the bottom of the blackbody cavity is better than 0.03 ℃. The expanded uncertainty is better than 0.1 ℃（k=2） over the entire temperature range.
2017 Vol. 38 (2): 129-134 [Abstract] ( 897 ) HTML (1 KB)  PDF (1130 KB)  ( 805 )
135 Multi-wavelength Effective Radiance Temperature Calibration and Characteristics Analysis of Traceable Approaches of the Blackbody Radiation Sources
YUAN Zun-dong, HAO Xiao-peng, WANG Jing-hui, WANG Tie-jun, XING Bo, BAI Cheng-yu, YANG Xue
DOI: 10.3969/j.issn.1000-1158.2017.02.02
The standard variable temperature blackbody radiation sources (VTBBs) and comparison facility of effective radiance temperatures established at the National Institute of Metrology of China are introduced. The approaches of radiance temperature comparison with standard blackbodies and of radiance temperature dissemination using standard radiation thermometers for multi-wavelength(waveband) effective radiance temperature calibration of the customer’s VTBBs are described. Characteristics of the effective emissivity and the probe temperature difference of VTBBs under calibration are evaluated based on calibration results of two typical VTBBs. The characteristics of three traceable methods and the influences on application of VTBBs are analyzed. The temperature controlled reproducibility is a novel concept of the temperature controlled reproducibility presented here and a key parameter but ignored by researches and applications before. The multi-wavelength effective radiance temperature calibration is a new traceable approach which can reduce or eliminate the influences of the effective emissivity and the probe temperature difference, and complementary with the traditional traceable method using standard contact thermometer. This approach is useful for evaluation of the VTBBs’ effective emissivity and probe temperature difference, and can give an optimal result for the VTBBs and very good in temperature controlled reproducibility.
2017 Vol. 38 (2): 135-140 [Abstract] ( 769 ) HTML (1 KB)  PDF (1106 KB)  ( 970 )
141 Research on Micro/nano Step Height Measurement System of Mirau Interference
GUO Xin,SHI Yu-shu,PI Lei,ZHANG Shu,LI Shi,LI Dong-sheng,GAO Si-tian
DOI: 10.3969/j.issn.1000-1158.2017.02.03
In order to realize the rapid measurement of the nanometer scale to the micro 3D step sample height, on the basis of ordinary optical microscope, a micro/nano step height measuring device is reconstructed. The whole hardware structure is designed. The measurement and control software and data processing software are programmed. Combined with Hilbert transform and wavelet transform, a new method of algorithm which is used for the reconstruction of 3D surface topography is proposed. The step samples of different height is used to test. The measurement results indicate that this system has high measurement accuracy and high repeatability, and its measurement range in vertical direction is not less than 50 μm.
2017 Vol. 38 (2): 141-144 [Abstract] ( 684 ) HTML (1 KB)  PDF (1131 KB)  ( 884 )
145 The Measurement of Single-layer Thickness of Graphene Materials by High Resolution Transmission Electron Microscopy
WANG Chen-ying,JING Wei-xuan,JIANG Zhuang-de, LIN Qi-jing,HAN Feng,LI Lei
DOI: 10.3969/j.issn.1000-1158.2017.02.04
The cross-sectional sample is made with the film of graphene material and is observed by high-resolution transmission electron microscopy (HRTEM). When the temperature is 20 ℃ , the value of the thickness of single-layer of graphene material measured by the software of HRTEM is 0.411 nm, otherwise, the cross-sectional of each layer of graphene material is not straight. The data of the edge of each layers could be obtained by the method of local shearing and increasing the gap, the value of thickness of the layer is 0.390 nm which is calculated by the histogram method, and the value of the uncertainty of the thickness is 0.042 nm. When the confidence level is 95%, the value of the thickness of single-layer graphene material is (0.390±0.086) nm. Compared with the nominal thickness of graphene,the calculated value of the thickness of single-layer graphene material is bigger. The difference of the thickness values is reasonable because there are gaps between the layers of grapheme material.nm. Compared with the nominal value of the graphene thickness，the single-layer thickness of grapheme-like was bigger. The different of the thickness values was thought to the gaps between the layer and the layer of grapheme-like.
2017 Vol. 38 (2): 145-148 [Abstract] ( 748 ) HTML (1 KB)  PDF (967 KB)  ( 1048 )
149 Research of Two Vision Accurate Measuring Method of Elastomers Conduction Band Groove Width
LIN Di,ZENG Zhi-qiang,WANG Jun-yuan,LI Xu,TANG Heng
DOI: 10.3969/j.issn.1000-1158.2017.02.05
For industrial inspection speed and accuracy requirements of elastomers conduction band width, the use of industrial cameras, lenses, computers and professional image processing software to build a set of machine vision systems and design a elastomer for the conduction band of the shallow groove width measurement device based on the image processing algorithms. Firstly, using the standard part to calibrate measurement system, the calibration values of the imaging system is calculated. Then the two visual measurement method are used to measure the upper and lower groove width of the 16 elastomers conduction band, and the groove width is calculated by corresponding calculation. Finally the actual measured values of the 16 parts and the three coordinate measuring results are compared. The results show that the measurement accuracy of the system can reach to micron level, which can meet the requirements of the measurement accuracy of elastomers conduction band width, and the measurement results are not influenced by the subjective factors.
2017 Vol. 38 (2): 149-152 [Abstract] ( 571 ) HTML (1 KB)  PDF (588 KB)  ( 469 )
153 The Research on Real-time Calibration Technology of Buoy Based on Analysis the Beidou Satellite Signal Fusion
JIA Wei-guang,CHANG Shuang,HU Bo,ZHU Li-ping,YU hui-li,LI dan
DOI: 10.3969/j.issn.1000-1158.2017.02.06
The high-precision technology of real-time kinematic (RTK) is studied, and through the multiple analytical satellite positioning signals (China Beidou, American GPS and Russian GLONASS) ,to achieve all-weather, high precision and full parameters (wave height, wave period and wave direction) real-time calibration technology. By repeated tests, the wave height measurement accuracy, single and binary star can reach 0.05m, multi satellite system can reach 0.02m, and the maximum error of the wave direction is 3.52°. Therefore, the fusion wave measurement by Beidou satellite can greatly enhance the technological level of Chinas wave instrument calibration.
2017 Vol. 38 (2): 153-158 [Abstract] ( 617 ) HTML (1 KB)  PDF (1803 KB)  ( 848 )
159 A drop contact angle estimation method based on balance principle
GUAN Xiao-dong,DI Jiu-sheng
DOI: 10.3969/j.issn.1000-1158.2017.02.07
A novel drop surface curve function is deduced based on the force balance principle, and the parameter of the function is acquired exploiting samples from the real image of the drop. The Newton-Raphson method is adopted to realize the curve fitting. Then a contact angle estimation method is proposed based on the novel function, forming a drop contact angle estimation method based on balance principle. The experiments are carried out by testing the image using JGW-360A contact angle measurement instrument for water drop with different materials. Canny method is adopted to acquire the edge of the drop to obtain the edge samples. Then the method is exploited to calculate the contact angle based on these samples. The method has been compared with the traditional image analysis methods. Results show that the method is the effective with a difference of 0.2°~0.3° from the traditional methods.
2017 Vol. 38 (2): 159-163 [Abstract] ( 633 ) HTML (1 KB)  PDF (868 KB)  ( 753 )
164 Uncertainty Evaluation Combined with Production Information for Product Inspection
WANG Han-bin,CHEN Xiao-huai,CHENG Zhen-ying,ZHONG Wei-hong,LI Hong-li
DOI: 10.3969/j.issn.1000-1158.2017.02.08
To reasonably reduce the influence of measurement uncertainty on the product conformity assessment, uncertainty evaluation combined with production information for product inspection was studied. A Bayes information fusion model combining processing information with measured information was established, with which the measurement result and its uncertainty were reestimated based on the posterior distribution of measured parameter, and the product conformity assessment was conducted according to the results after information fusion. The method to calculate Bayes prior parameters by quality control information was proposed. Simulation experiment and example analysis results show that combining production information into the measurement uncertainty evaluation in product inspection can effectively expand the range of conformance zone and reasonably reduce the workload of conformity assessment.
2017 Vol. 38 (2): 164-167 [Abstract] ( 646 ) HTML (1 KB)  PDF (2036 KB)  ( 596 )
168 Research on Search Area for Flatness Error Based on the Measurement Uncertainty
WANG Ao-sheng
DOI: 10.3969/j.issn.1000-1158.2017.02.09
In order to avoid the problem of excessive or inadequate iterations in flatness error assessement, 0.467 times the ratio of measurement uncertainty to step is used as termination condition. It is worthless of continuing approximate when search area is 0.467 times less than the ratio of measurement uncertainty to step. It is more scientific and reasonable than termination of time or iterations or fitness in the flatness error assessment.
2017 Vol. 38 (2): 168-170 [Abstract] ( 716 ) HTML (1 KB)  PDF (284 KB)  ( 491 )
171 Research on the Calibration Method of Reference Solar Cell
ZHANG Jun-chao,XIONG Li-min,MENG Hai-feng,HE Ying-wei,ZHANG Bi-feng
DOI: 10.3969/j.issn.1000-1158.2017.02.10
Based on differential spectral responsivity method, a calibration equipment for reference solar cell is established. The absolute responsivity of reference cell varied with temperature of cell and irradiance intensity of bias light are analyzed. The relationship between the short circuit current and the bias current of the solar cell is obtained by numerical simulation techniques. The uncertainty of the result is 1.2% (k=2). Based on outdoor method, a reference cell calibration equipment is established. A detailed uncertainty evaluation of the result is carried out, the value is 2.38% (k=2). Through numerical calculation and analysis of the En value (0.95), it is found that the results measured by the two methods are equivalent.
2017 Vol. 38 (2): 171-174 [Abstract] ( 792 ) HTML (1 KB)  PDF (322 KB)  ( 739 )
175 Fish Movement Behavior Characteristic Parameter Extraction Based on Visual Perception
CHENG Shu-hong,LI Lei-hua,LIU Jie,QIAN Lei
DOI: 10.3969/j.issn.1000-1158.2017.02.11
Against how to use biomonitoring technology to improve the recognition rate of abnormal water quality, the evaluation factors of biological water quality is studied and an improved algorithm of fish center is proposed. On the basis of this algorithm, it introduced new behavior characters of fish movement, such as fish dispersion, curvature and vicinity feature, carried out pretreatment for these characteristic parameters, established databases for evaluation factors of abnormal water quality and took the evaluation factors as inputs of support vector machine (SVM) to identify abnormal water quality. The results of experiment show that by introducing characteristic parameters for evaluation of abnormal water quality, its identification effect is better than other methods and the recognition rate is over 92%.
2017 Vol. 38 (2): 175-178 [Abstract] ( 635 ) HTML (1 KB)  PDF (451 KB)  ( 1251 )
179 Development of Aggregate Particle Size On-line Detection System
LUO Man,YANG Jian-hong,CHEN Si-jia,FANG Huai-ying
DOI: 10.3969/j.issn.1000-1158.2017.02.12
Digital image processing is proposed to measure the size of aggregate.Illuminant source commonly has two installation methods,which are front illuminant installation and backlight installation. Aggregate has two motion states,which are lying on the conveyer and falling from conveyer,in production line. A proper illuminant installation is proposed by studying two motion states of aggregate. When shooting the falling aggregate,speed of conveyer,installation angle of conveyer,thickness of aggregate and camera installation height would effect shooting results.Getting optimized parameters by studying the effects of these factors on the aggregate dispersion using EDEM simulation software.By comparing image processing effects and size distribution statistical results of three shooting methods, a practical way to detect aggregate size distribution is proposed.
2017 Vol. 38 (2): 179-183 [Abstract] ( 829 ) HTML (1 KB)  PDF (1510 KB)  ( 986 )
184 Dynamic Calibration of Accelerometer Using Short Shock Excitation
HU Hong-bo,SUN Qiao,BAI Jie
DOI: 10.3969/j.issn.1000-1158.2017.02.13
A general description of calibration methods for accelerometers is presented, with characterization made about their strengths and weaknesses. An accelerometer, selected as an example, is dynamically calibrated using shock excitation, with the device and calibration process introduced in detail. A spring-mass system with one-degree-of-freedom is applied to describe the behavior of the accelerometer and system identification is applied to determine the parameters value. The calibration result, which is the dynamic characterization of the accelerometer, is analyzed, and further, a comparison of calibration results is made with primary vibration calibration.
2017 Vol. 38 (2): 184-188 [Abstract] ( 760 ) HTML (1 KB)  PDF (841 KB)  ( 645 )
189 Wear Condition Recognition of Lathe Tool Based on Singular Value Decomposition and Grey Target Decision Methods
ZHU Jian-min,ZHAO Quan-long,HE Dan-dan
DOI: 10.3969/j.issn.1000-1158.2017.02.14
In allusion to the problems that random noise interferes the time domain vibration signal extraction, and limited lathe tool wear condition recognition accuracy. This study proposed a time domain characteristics extraction method of tool wear signals which firstly extracts the time domain characteristics of the lathe tool vibration signal with wavelet packet transform and correlation coefficient methods, then denoises the time domain characteristics with singular value decomposition(SVD) method. The most relevant wear characteristics of lathe tool weariness are selected as reference characteristic sequence to calculate the similarity association degrees with other wear characteristic sequences. Then the weight of each time domain wear characteristics are gain through normalization process of similarity association degrees, and the comprehensive measurement of time domain characteristic of each wear signal are calculated with grey target decision method in order to determine the tool wear condition of the lathe tool. Experiment results indicate that the proposed method can filter the random noise effectively.
2017 Vol. 38 (2): 189-192 [Abstract] ( 737 ) HTML (1 KB)  PDF (360 KB)  ( 808 )
193 APMP Pilot Comparison of Low-g Shock Acceleration Primary Calibration
SUN Qiao,HU Hong-bo,BAI Jie
DOI: 10.3969/j.issn.1000-1158.2017.02.15
As pilot lab, National Institute of Metrology, organized Asia Pacific Metrology Programme pilot comparison of primary low-g shock acceleration calibration from August, 2013 to December, 2014. The comparison covers primary shock calibration systems using laser interferometry with two basic types of low-g shock exciters from 4 participating labs. The peak value of shock acceleration for comparison of monopole shock pulse is from 500m/s2 to 5000m/s2 with pulse duration from 0.5ms to 5ms, and for comparison of dipole shock pulse is 1000m/s2 with pulse duration from 0.03ms to 0.2ms. The comparison results show that the deviations of participants’ measurement results from reference values are within the associated uncertainties.
2017 Vol. 38 (2): 193-196 [Abstract] ( 554 ) HTML (1 KB)  PDF (290 KB)  ( 591 )
197 Study of Glass Hydrometer Calibration by Hydrostatic Weighting
CHEN Chao-yun,WANG Jin-tao,LI Zhi-hao,SUN Bin
DOI: 10.3969/j.issn.1000-1158.2017.02.16
Glass hydrometers calibration uses silicon ring as a reference standard solid density, tri-tretradecane with density stability and low surface tension as the standard working liquid, CCD image measurement system to align the scale of hydrometer and liquid surface, designes a glass hydrometer calibration system. According to twice glass hydrometer weighing in the air and liquid can calculate the correction value of the current scale. To measure the density range of 770~790 kg/m3, a resolution of 0.2 kg/m3 of hydrometer is used. The results of measurement comparing with that of the Physikalisch-Technische Bundesanstalt,verify the validity of the calibration system.
2017 Vol. 38 (2): 197-199 [Abstract] ( 699 ) HTML (1 KB)  PDF (311 KB)  ( 505 )
200 A Driving and Digital Signal Processing System of Gas Ultrasonic Flow-meter based on FPGA & DSP
FANG Min,XU Ke-jun,WANG Wei,ZHU Wen-jiao,SHEN Zi-wen
DOI: 10.3969/j.issn.1000-1158.2017.02.17
The driving and digital signal processing system of ultrasonic gas flow-meter based on the FPGA & DSP dual core structure was developed.It is realized by taking advantage of the high operating frequency and abundant resource inside FPGA to control the high-speed ADC & DAC and storage the data. On the other hand, the implementation of real time digital signal processing relies on the use of high-speed computing capacity of DSP. To address the ultrasonic echo signals generated by the use of sinusoidal excitation, a new method called variable threshold tracking the peak of the echo signal is proposed, based on the experimental data statistics. It aims at extracting the characteristic waves and weakens the influence of noise. The effectiveness of the system and method was verified by the results of gas calibration experiments.
2017 Vol. 38 (2): 200-204 [Abstract] ( 684 ) HTML (1 KB)  PDF (1290 KB)  ( 882 )
205 The Ultrasonic Mass Flow Measurement Method of Light FuelBased on the Artificial Neural Network Model
ZHANG Xiao-zhong,MENG Fan-qin,SONG Sheng-kui
DOI: 10.3969/j.issn.1000-1158.2017.02.18
The relationship between the light fuel ultrasonic velocity, its density and temperature is studied on the basis of a large amount of experimental data. The artificial neural network model is established to predict light fuel density of various batches and various manufactures, the predicting error of the density is less than 0.24%. A method of mass flow measurement by a ultrasonic flow meter has been given. With no need for the fuel standard density, the ultrasonic flow meter can measure the light liquid fuel mass measurement, the repeatability error of mass flow of a prototype proved to be less than 0.35%.
2017 Vol. 38 (2): 205-208 [Abstract] ( 575 ) HTML (1 KB)  PDF (1049 KB)  ( 639 )
209 Parameter Identification and Optimization of the MFF Model Based on the Particle Swarm Optimization Algorithm
TENG Feng-cheng,HAO Yu,LIN Xiao-le
DOI: 10.3969/j.issn.1000-1158.2017.02.19
Based on the flux theory and Monte-Carlo method, magnetic fluid transmission characteristics are analyzed and the magnetic fluid film (MFF) models of the transmittance and the sensor are established. Using PSO algorithm, the parameter identification of MFF transmission model is carried out. The influences of number of groups, iterations, inertia weight and acceleration factors on operating results of algorithm are analyzed, and the best combination of parameters is selected. The experiment platform of MFF current sensors is built, the impact of MFF transmission of the MFF thickness and particle concentration is analyzed. The results of experiment and simulation show that the predictive error of the model within 2.3% and the measurement sensitivity of the MFF current sensor reach 12 μW/A.
2017 Vol. 38 (2): 209-214 [Abstract] ( 691 ) HTML (1 KB)  PDF (1701 KB)  ( 536 )
215 In-situ Efficiency Estimate of Induction Motor on BF Algorithm
SUN Guan-qun,ZHANG Li-suo
DOI: 10.3969/j.issn.1000-1158.2017.02.20
Using bacterial foraging algorithm of optimized, a method to estimate efficiency of induction motor is presented. It relies on measuring the stator current, the stator voltage, stator resistance, the power input and the motor speed, without the need for no-load and locked-rotor test. Through a 5.5 kW induction motor test, the results and other industry better algorithms are compared, including the particle swarm optimization algorithm, immune algorithm, as well as the measured torque gauge method. The results show that the method can estimate the motor efficiency accurately, and is simple and low cost.
2017 Vol. 38 (2): 215-219 [Abstract] ( 619 ) HTML (1 KB)  PDF (580 KB)  ( 564 )
220 An Improved Empirical Mode Decomposition Method Based on Shielding Technology
ZHANG Shu-qing,SHI Rong-yan,MA Chun-li,DONG Guo-xin, DONG Yu-lan,LI Sha-sha,JIANG Wan-lu
DOI: 10.3969/j.issn.1000-1158.2017.02.21
Empirical mode decomposition(EMD) has superior adaptability as to localize the non-stationary and non-linear signals at different time scales correctly. But there is modal aliasing phenomenon when the frequencies of signal consisting components are similar to each other. In order to solve the problem above, shielding technology is introduced to optimize traditional EMD. A shielding signal with certain frequency is added to the original signal to exclude low frequency components from in the intrinsic mode function(IMF) where high-frequency component existed, while the shielding signal itself eliminated the influence on the IMF by acquiring average after adding or subtracting decomposition twice. Simulation and practical application have proved that this improved method can overcome aliasing modes phenomenon effectively, providing a new way to improve the EMD.
2017 Vol. 38 (2): 220-224 [Abstract] ( 514 ) HTML (1 KB)  PDF (1827 KB)  ( 518 )
225 An Accurate Determination Method of Characteristic Impedance of Transmission Line Based on Multi-TRL Algorithms
WANG Yi-bang,LUAN Peng,WU Ai-hua,LIANG Fa-guo,SUN Jing
DOI: 10.3969/j.issn.1000-1158.2017.02.22
On wafer S-parameter accuracy mainly depends on the characteristic impedance of transmission line standard. An accurate method of determination of characteristic impedance of coplanar waveguide is researched, which involves the deduction and optimization of Multi-TRL（Multi-Thru Reflect Line）algorithms to obtain the propagation constant, and uses the propagation constant determines characteristic impedance. The extraction software “wyb” of propagation constant and characteristic impedance were developed, and the method was validated against commercial Multi-TRL software Wincal by the same input of the measurements of calibration standards at on-wafer reference material RM8130. The result shows that, between 5~10 GHz, the relative error of the magnitude of characteristic impedance is within ±0.6％, and the phase is within ±0.55°.As frequency goes above to 40 GHz , the relative error of the magnitude of characteristic impedance is within±0.2%, the phase error within ±0.4°.
2017 Vol. 38 (2): 225-229 [Abstract] ( 767 ) HTML (1 KB)  PDF (2706 KB)  ( 784 )
230 The Method of BER Estimation on Digital Communication Baseband Equipment
YU Qing-hua,SHEN Xiao-qing,CHEN Si,XIA Wei,QIU Bin
DOI: 10.3969/j.issn.1000-1158.2017.02.23
A method using EVM and phase noise to evaluate the digital baseband equipment is proposed instead of BER for it is self-tested in close-loop and can’t be traceable. The relationship between EVM and BER in additive white Gaussian noise is analyzed and the empirical formula using EVM to predict BER is given. The effect of phase noise on BER is analyzed providing a way to predict BER when the phase noise come to a sharp change. A digital baseband equipment for testing object, the difference between the predicted results and the measured results is no bigger than 12.5% in 3 months after the predicting formula is established. The results show that the use of EVM and phase to evaluate the performance of the digital baseband equipment instead of BER is available in additive white Gaussian noise environment. What’s more, EVM reflects the effects in process directly and can be traced to the national standard.
2017 Vol. 38 (2): 230-233 [Abstract] ( 575 ) HTML (1 KB)  PDF (558 KB)  ( 1298 )
234 Solution of Building the Standard Laboratory of Radon
ZHANG Yang,XU Ming,SUN Gao-feng,YIN Guo-hui,HU Mao-zhong, ZOU Rong-hu,WANG Yin-dong,CHENG Zhi-wei,FENG Tian-cheng
DOI: 10.3969/j.issn.1000-1158.2017.02.24
The standard laboratory of radon plays an important role in the tracing and transmitting of value of radon concentration. But there are many problems in the process of building the standard laboratory of radon, which are gas leaking of solid radon source, inconformity between theoretical value and experimental value of radon concentration in laboratory, and crystallization of liquid radon source. Measures were taken to solve these problems, such as changing the gas washing canal of radon, optimizing the model of gas washing, multiple sealing and filtering, building empirical curve, and so on. It indicated that the relative deviation between theoretical value and experimental value of radon concentration in laboratory was less than ±3.8%, and the long time stability of liquid radon source less than 0.7%, which meet the requirment of measurment and methods established metrology.
2017 Vol. 38 (2): 234-237 [Abstract] ( 469 ) HTML (1 KB)  PDF (1023 KB)  ( 574 )
238 Determination of Biological Toxicity of Medical Institutions Waste Water by the Method of Luminescent Bacteria
LI Yong-liang,LI Jian,LI Gui-lian,YU Ting-ting
DOI: 10.3969/j.issn.1000-1158.2017.02.25
Vibrio Fischeri as spawn, a comprehensive test of the waste water discharged by medical institutions was carried out, combine with the determination of fecal coliform. Monitoring results of fecal flora of waste water conformed to the requirements of the corresponding standard limit, but medical waste water with biological toxicity generated certain biological inhibition rate to photogenic bacterium. The waste water of infectious diseases and tuberculosis medical institutions possessed biological inhibition rates as high as 44.7%and 49.8%. The inhibition rate of waste water from traditional Chinese medicine medical institutions caused a minmum inhibition rate of 8.1%. The experimental results showed that the luminescent bacteria method could be applied to the determination of waste water of medical institutions.
2017 Vol. 38 (2): 238-241 [Abstract] ( 623 ) HTML (1 KB)  PDF (326 KB)  ( 428 )
242 Study on Recognition Algorithm of P300 Based on Wavelet Transform and Blind Source Separation
HU Chun-hai,XIN Si-xu,LIU Bin,LIU Yong-hong
DOI: 10.3969/j.issn.1000-1158.2017.02.26
A new P300 EEG recognition algorithm is proposed. Complex operation and miscellaneous data of multichannel and multi-featured are avoided. First, aiming at selecting optimum wavelet base, which is lack of theoretical basis in wavelet transform of P300, a method is proposed based on SNR and RMSE, and the noise of original signals coherent averaged is removed combining the result of SPWD time and frequency analysis, and observations are decomposed by the preferred JADE algorithm. Then, aiming at selecting automatically and avoiding excess decomposition after BSS of P300, combining G1, temporal and spatial analysis model is built, P300 component is optimum extracted automatically and mapped to electrodes. Finally, in order to improve BCI system application online, combining EA with SFFS, and the training model of 6-dimension feature vector is built so that classified and recognized by C-SVM. As is shown by the experimental results, compared with traditional data processing technique, the effect of P300 component extraction, accuracy and speed of system recognition are improved visibly.
2017 Vol. 38 (2): 242-246 [Abstract] ( 586 ) HTML (1 KB)  PDF (3971 KB)  ( 802 )
247 Accurate Plasmid DNA Copy Concentration Quantification by Digital PCR
DONG Lian-hua,SUI Zhi-wei,WANG Jing,FU Bo-qiang
DOI: 10.3969/j.issn.1000-1158.2017.02.27
NIM established two digital polymerase chain reaction (dPCR) assays for quantifying the plasmid DNA sample, including designing two pairs of specific primer and probe, optimizing PCR amplifying conditions and excluding the DNA contamination in the PCR mastermix. The measurement results by simplex and duplex dPCR are compared. The DNA sample is successfully quantified by the established dPCR method and the measurement uncertainty is eventually evaluated. The measurement result with its expanded uncertainty (k=2) is (8.06±0.55)×103copies/mg, it agree well with the reference value within the standard uncertainty and very close to the reference value.
2017 Vol. 38 (2): 247-251 [Abstract] ( 681 ) HTML (1 KB)  PDF (964 KB)  ( 1232 )
252 Evaluating and Analyzing Measurement Uncertainty Based on the Theory of Evidence
YU Xue-feng,YU Jie,WANG Ke,ZHANG Kai-wei
DOI: 10.3969/j.issn.1000-1158.2017.02.28
Deal with the limitations of GUM recommendations to express the measurement uncertainty based on a probabilistic and statistical theory, a more general approach which framed within the theory of the evidence was proposed. The method can represent the measurement result and its associated uncertainty in terms of random-fuzzy variables. An exhaustive mathematical framework and RFV membership functions was established according to the available information. The procedure for expressing the measurement uncertainty in terms of RFV was given by simple examples. The experimental results reported show that RFV are capable of both providing all the intervals of confidence and representing the different contributions to uncertainty. By compared with the approach of the GUM, the RFV method allows representing the dispersion of the values that could reasonably be attributed to the measured in a more suitable way than the probability theory, especially when no negligible nonrandom effects are present.
2017 Vol. 38 (2): 252-256 [Abstract] ( 684 ) HTML (1 KB)  PDF (765 KB)  ( 708 )
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