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2023 Vol. 44, No. 4 Published: 2023-04-28

	495	Development of Picker-type Calorimeter for Specific Heat Capacity Measurement Based on Flow Method
		GUI Ling-yan,MENG Xian-yang,LI Dong-dong,WU Jiang-tao
		DOI: 10.3969/j.issn.1000-1158.2023.04.01
		In order to study the apparent molar heat capacity of the dilute solution, a Picker-type flow calorimeter for specific heat capacity measurement based on the differential method is developed. It has a symmetrical dual-cell structure, with one tube serves as working cell and the other serves as reference cell. Using water as the reference fluid, the ratio of specific heat capacity of the sample and reference fluid is obtained by adjusting the balance of the temperature measurement bridge before and after the injection. The system is designed to operate at temperatures 278K to 343K and atmospheric pressure. The verification experiment is carried out using aqueous sodium chloride (NaCl) and the average relative deviation between the experimental data and the literature values is within 1%, which showed that the system is of good reliability and high accuracy.
		2023 Vol. 44 (4): 495-502 [Abstract] ( 176 ) HTML (1 KB) PDF (33066 KB) ( 65 )

	503	Study on the Measurement of the Emissivity Distribution of Flat PlateRadiation Source Based on the Integrating Sphere Reflection Method
		LIU Guang-yu,HUAN Ke-wei,AN Bao-lin,DONG Wei,ZHAO Yun-long,SONG Xu-yao,YUAN Zun-dong
		DOI: 10.3969/j.issn.1000-1158.2023.04.02
		The measurement of emissivity distribution characteristics is an important basis for evaluating the radiation uniformity of large-aperture radiation sources, but the related research is relatively scarce at present. Therefore, a measurement system for the emissivity distribution characteristics of the infrared radiation source is designed and built based on complete hemispherical laser integrated reflection scheme. The performance of the measurement system is studied, the stability of the laser light source subsystem is evaluated, and the experiment of measuring the emissivity distribution characteristics of surface radiation source is carried out at 3 W laser power. The results show that the measurement system has good stability. Taking the surface of standard gold plate as the research object, the repeatability of multiple measurement results is 0.30%; The experimental measurement of emissivity distribution of carbon based surface radiation source is carried out, and the distribution cloud map of emissivity of surface radiation source is obtained, the uniformity of emissivity is 98.1%.
		2023 Vol. 44 (4): 503-507 [Abstract] ( 201 ) HTML (1 KB) PDF (34376 KB) ( 149 )

	508	Investigation of the Steady State Method for Thermal Conductivity Measurement and its Data Processing Method
		HUANG Si-yu,WEI Chi-xu,ZHENG Lian-hui
		DOI: 10.3969/j.issn.1000-1158.2023.04.03
		The shortcomings and problems of the two current methods for measuring heat dissipation rate are analyzed. A new method, isothermal adiabatic method, for measuring heat dissipation rate is proposed, by which the measurement error can effectively reduced. After the quadratic curve fitting of the heat dissipation rate data by Excel chart and the derivation of the quadratic function, the value of temperature change rate dθ/dt in steady state is obtained. The temperature change rate by the quadratic function is more accurate than that obtained by the traditional method. By using the isothermal adiabatic method, the relative error of the thermal conductivity of the styrene butadiene rubber and PVC are -1.96% and 0.95% respectively, demonstrating the elimination of the error.
		2023 Vol. 44 (4): 508-513 [Abstract] ( 146 ) HTML (1 KB) PDF (20774 KB) ( 92 )

	514	Research on Structural Displacement Tracking Monitoring Based on Surveillance Camera Videos
		GAO Chao,WANG Liu-qi,NI Tong-yuan,YANG Yang,LIU Jin-tao,GU Chun-ping
		DOI: 10.3969/j.issn.1000-1158.2023.04.04
		Based on the video of surveillance camera and digital image processing, a method to characterize the displacement of structural position feature points was designed. Firstly, the circular target is placed on the structure. The template matching method is used to detect the initial image coordinate region of the circular target, and the region of interest(ROI) is cut out; Then use Otsu method to determine the binarization threshold of the region, extract the coordinates of the target contour points, use the least square method to fit the contour into an ellipse, and obtain the coordinates of the center of the ellipse and the size of the long and short axis. The ratio of the diameter of the circular target to the major and minor axis is the conversion coefficient η; The product of the change of the ellipse center coordinate and the conversion coefficient is the displacement of the structure in the actual corresponding coordinate direction. The experimental results shown that the relative error of this method was less than 3% in the horizontal and vertical displacement loading experiments which compared with the high-precision displacement meter. And it can realize millimeter displacement monitoring and accurately characterize the displacement change of the corresponding characteristic points of the structure.
		2023 Vol. 44 (4): 514-520 [Abstract] ( 140 ) HTML (1 KB) PDF (53543 KB) ( 59 )

	521	Auto-focusing Technology in Perpendicular Length Measurement of Video Measuring Machine
		CHE Yi-feng,YANG Guo-shun,CHEN Li-guo
		DOI: 10.3969/j.issn.1000-1158.2023.04.05
		The higher the auto-focusing accuracy is, the smaller the perpendicular length measurement error of video measuring machine would be. The improved Tenengrad gradient evaluation function is selected by comparing the performance indexes of definition evaluation function.The full window is selected as the focus window. A search strategy combining rough and fine focus is proposed. In rough focus, mountain climbing search algorithm combined with binary search algorithm is used. And Gaussian curve fitting method combined with global search algorithm is used in fine focus. The experimental results show that the auto-focusing algorithm has good robustness and high accuracy which can reach 5μm (1/20 depth of field), and the average focusing time is 10 seconds which can meet the real-time requirements.
		2023 Vol. 44 (4): 521-526 [Abstract] ( 166 ) HTML (1 KB) PDF (15812 KB) ( 80 )

	527	A Method for Obtaining Edge Radius of Aeroengine Blade Based on Incomplete Point Cloud Data
		CAO Guo-qiang,GUO Xu,YE Chang-long,DING Jian
		DOI: 10.3969/j.issn.1000-1158.2023.04.06
		The non-contact measurement technology does not rely on the original design model of the blade and quickly obtains the key geometric parameters of the blade, but the point clouds obtained in the area of high curvature of the edge of the blade are sparse and scattered, so that it is difficult to obtain the radius of the leading edge of the blade. In order to solve this problem, a method to obtain the leading edge radius of blade based on incomplete point cloud data is proposed. In this method, the contours of leaf basin and leaf back are obtained by point cloud segmentation, and the leaf edge arc tangent to leaf basin and leaf back is obtained by dichotomy approximation method. Compared with the results obtained by measuring the blade edge radius by the contact CMM, the deviation is less than 30%, which is in line with the expectation.This method can improve the point cloud distortion of non-contact measurement of high curvature surface to a certain extent, and provides a useful reference from the rapid reconstruction of blades.
		2023 Vol. 44 (4): 527-533 [Abstract] ( 153 ) HTML (1 KB) PDF (68879 KB) ( 80 )

	534	Principle andTechnical Progress of Flux-actuated Superconducting Switches
		WANG Shi-jian,GAO He,LI Jin-jin,WANG Xue-shen
		DOI: 10.3969/j.issn.1000-1158.2023.04.07
		Superconductivity transition edge sensor (TES) has been widely used in photon metrology, optical quantum communication, X-ray radiation, cosmic microwave detection and other detection fields. For the large-scale integration TES application, the time-domain multiplexing (TDM) superconducting quantum interference devices (SQUIDs) are used to realize the signal readout. Flux-actuated superconducting switches based on Josephson junctions are the key factors for multiplexing readout system. Superconducting switches improve the multiplexing factor of the TDM system, and increase the integration level of TES. The principle, characteristic parameters, the design principles, and the application status in the TDM system of flux-actuated superconducting switches are introduced. This will provide technical support for the research of superconducting switches.
		2023 Vol. 44 (4): 534-539 [Abstract] ( 170 ) HTML (1 KB) PDF (62900 KB) ( 78 )

	540	Research on Uncertainty Evaluation Methods of Straightness of Straight Edge Based on Monte Carlo Method
		LI Yuan-feng,MENG Ling-chuan,HUANG Yao,YANG Hao-tian
		DOI: 10.3969/j.issn.1000-1158.2023.04.08
		The straightness uncertainty of straight edge in least-square rule and in minimum-zone rule have been evaluated by Monte Carlo method (MCM). Comparing with the straightness uncertainty evaluated by guide to the expression of uncertainty in measurement (GUM), it's been found that the straightness uncertainty in least-square rule evaluated by MCM is 0.028 μm less than that by GUM and the straightness uncertainty in minimum-zone rule evaluated by MCM is 0.026 μm less than that by GUM. It has been confirmed that both the methods are valid for evaluating the straightness uncertainty of straight edge at a certain numerical tolerance of 0.05 μm. Kolmogorov-smirnov test, jarque-bera test, normal probability plot, skewness and kurtosis test were employed as the statistic testing methods. By employing specific statistic testing method on measurand, it's been found that the kurtosis deviation of measurand distribution from normal distribution is responsible for the uncertainty difference.
		2023 Vol. 44 (4): 540-548 [Abstract] ( 146 ) HTML (1 KB) PDF (67558 KB) ( 115 )

	549	Research on the Properties of Ti Superconducting Thin Films in SiO2-SiNx System Optical Resonator
		LIU Hai-yan,SUN Xiao-ying,LI Jing-jing,WANG Xue-shen,CHEN Jian,GAO He,ZHOU Zhe-hai,XU Xiao-long
		DOI: 10.3969/j.issn.1000-1158.2023.04.09
		Well-designed optical cavity is an effective method to improve the optical efficiency of superconducting transition edge sensor (TES). Changes in the multi-layer films' thickness of the optical cavity affect not only the optical efficiency but also the superconducting performance of TES due to the changes in film's stress. The Ti film is selected as the superconducting material of the TES functional layer due to its excellent characteristics at low temperature. Also, the SiO2-SiNx system is selected as the optical cavity film. Through the numerical simulation of the film thickness, the influence of the thickness of the SiO2-SiNx system optical resonator film on the optical absorption efficiency of Ti-TES is determined. Analyzed the tendency of the stress of the SiO2-SiNx system optical resonator with different film thicknesses, and finally prepared TES with different thicknesses of the SiO2-SiNx optical resonator, and tested the optical absorption efficiency to verify the SiO2-SiNx The influence of the film thickness of the system optical resonator on the Ti-TES optical absorption efficiency.
		2023 Vol. 44 (4): 549-554 [Abstract] ( 134 ) HTML (1 KB) PDF (73900 KB) ( 64 )

	555	Sensitivity Optimization Method of Vibrating Tube Densitometer
		WANG Si-xian,ZHANG Jing-yue,WANG Jin-tao
		DOI: 10.3969/j.issn.1000-1158.2023.04.10
		Based on Euler-Bernoulli beam theory, an inhomogeneous partial differential equation describing the resonator of vibrating tube densitometer is constructed and solved. An analytical equation for computing the sensitivity of the resonator is given. Based on the analytical equation and combined with the wet modal analysis of ANSYS Workbench, the variation rule of resonator sensitivity under different structural sizes and working modes is analyzed. According to the analysis results, 13 straight tube samples with different structure sizes were selected and fabricated. The validity of the analytical formula was verified by experiments on these samples using force hammer modal analysis method. It is found that the sensitivity of the straight tube resonator can be significantly improved by a series of measures including reducing the effective length, increasing the inner radius and taking the wall thickness to the critical value, up to -1.904Hz·kg^-1·m³
		2023 Vol. 44 (4): 555-561 [Abstract] ( 135 ) HTML (1 KB) PDF (58823 KB) ( 65 )

	562	Motion Attitude Measurement Method of Bogie Based on Six Degrees of Freedom Vibration Table
		HAN Zhi,CHEN Chun-Lei,FU Qiang,HAPO Jin-Fei,CHENG Zhao-Yang
		DOI: 10.3969/j.issn.1000-1158.2023.04.11
		Track geometry dynamic detection is an important means to ensure the safe operation of trains.The reliability of track geometry dynamic detection is affected by the veracity of motion attitude measurement results of vehicle bogie.In order to improve the accuracy of motion attitude detection results of vehicle bogie,a method of frame motion attitude measurement based on six degree of freadom shaking table was proposed.Different excitation signals are applied to the bogie.Four triaxial accelerometers are used to collect acceleration signals.The acceleration signal is converted to simulate the displacement and rotation of bogie's geometric center through the frequency domain integration method of fast Fourier transform and attitude calculation algorithm based on displacement data.The verification test of bogie attitude measurement method was carried out with the input signal of six degree of freadom shaking table as the standard.The results show that the lateral displacement,vertical displacement,roll and swing root mean square difference of bogie attitude measurement algorithm are less than 0.04mm,0.03mm,0.05° and 0.03° respectively.
		2023 Vol. 44 (4): 562-567 [Abstract] ( 148 ) HTML (1 KB) PDF (79249 KB) ( 73 )

	568	Effects of Pressure Medium on Dynamic Characteristics of Pressure Measuring System with Transmission Pipe
		WANG Hong-bo,YANG Yang-zhongfu,WANG Xiao-wen,WANG Chen-chen
		DOI: 10.3969/j.issn.1000-1158.2023.04.12
		When using shock tube for dynamic calibration of pressure measuring system with transmission pipe, the medium in the pipe may change the dynamic characteristics of pressure measuring system, which in turn affects the evaluation of the performance of the pressure measuring system. By establishing the pressure propagation model in the pipe, the principle and factors affecting the dynamic characteristics of the pressure measuring system with transmission pipe were analyzed, and the dynamic pressure calibration experiment using shock tube for pressure measuring system with damping hole and without damping hole under the conditions of air, decanedioic acid and silicone grease was carried out. The experimental results showed that the medium had a significant effects on the dynamic characteristics of the pressure measuring system, such as rise time and resonance frequency. The resonance frequency varies by more than 10 times.
		2023 Vol. 44 (4): 568-574 [Abstract] ( 144 ) HTML (1 KB) PDF (128800 KB) ( 78 )

	575	Research on the Bias Combination Algorithm for Programmable Josephson Junction Array
		LIANG Pan,QIAN Lu-shuai,REN Wei,SUN Ying-li,CUI Chao-yi,ZHAO Jian-ting,ZHANG Dan-dan
		DOI: 10.3969/j.issn.1000-1158.2023.04.13
		In the programmable Josephson quantum voltage standard system, fast and accurate calculation of the bias combinations of Josephson junction sub-arrays is the premise to achieve the accurate output of quantum voltage. The traditional enumeration-index algorithm searches for the optimal solution by traversing all possible bias combinations, resulting in low computational efficiency and difficulty in adapting to special application scenarios such as quantum voltage aperiodic continuous transformation outputs. Based on the above,a bias combination algorithm is proposed for the ternary programmable Josephson junction array. Firstly, the sub-arrays are grouped adaptively according to the number of Josephson junctions in each one,and then the preliminary bias combinations are quickly calculated. Furthermore, the approximate calculation method and quantization error compensation method are combined to overcome some specific problems in the preliminary bias combinations, such as sub-arrays failure, sub-resolution design, and so on. Experimental results show that the mentioned algorithm can find the optimal bias combination under various conditions, and the computational efficiency is much better than the traditional enumeration-index algorithm.
		2023 Vol. 44 (4): 575-581 [Abstract] ( 137 ) HTML (1 KB) PDF (7419 KB) ( 103 )

	582	Microgrid Fault Diagnosis Based on Deep Transfer Learning and LSTM Network
		WU Zhong-qiang,LU Xue-qin
		DOI: 10.3969/j.issn.1000-1158.2023.04.14
		A microgrid fault diagnosis method based on the combination of deep transfer learning and long-short-term memory network is proposed, which can be used to diagnose microgrids fault with different structures. First, wavelet packet transform is used to extract the feature vectors of fault as the input of the network; second, source domain data samples is used to pre-train the fault diagnosis model built by long short-term memory network, and relevant parameters is saved; Then transfer learning is used to migrate the parameters in the pre-training model to the domain adaptive network to obtain the combination model of deep transfer learning and long-short-term memory network; finally, the model is fine-tuned and migrated according to the labeled data (source domain data) and target domain data, and the single microgrid fault diagnosis model is transferred to other microgrids of different structures. The test results show that the proposed method can detect and identify any type of faults in microgrids of different structures. The mean square error of the identification result is 8.5905×10^-5, smaller two orders of magnitude compared with the long-short-term memory network model before adaptive adjustment, the recognition effect is better and the diagnosis accuracy is obviously improved.
		2023 Vol. 44 (4): 582-590 [Abstract] ( 157 ) HTML (1 KB) PDF (178922 KB) ( 92 )

	591	Analysis and Evaluation on the Uncertainty of Doppler Frequency Measurement Based on LDV Velocity Measurement Algorithm
		ZHANG Yu-wen,CUI Li-shui,XIE Dai-liang,YANG Zhao-xin
		DOI: 10.3969/j.issn.1000-1158.2023.04.15
		In order to clarify the applicability of the low-speed results of the laser Doppler velocimeter (LDV) calibrated by the spinning-disc facility, it is analyzed that the uncertainty of velocity depends on the uncertainty of both the interference fringe spacing in the measuring volume and Doppler frequency. As the Interference fringe spacing is independent of the fluid velocity the possible difference of uncertainty in between the high velocity and the low velocity is only related with the Doppler frequency algorithm at different velocity. The uncertainty of Doppler frequency caused by the algorithm at different velocity is analyzed with Monte Carlo method (MCM) for evaluation of measurement uncertainty. The result shows that the relative uncertainty of the Doppler frequency caused by the algorithm is less than 0.03% in the range of 0.1~340m/s.The obvious difference of uncertainty has not been found in the different points of velocity investigated. The budget resulting from Doppler frequency accuracy to the uncertainty of velocity measured is less than 0.013%. It is concluded that the calibration result at low velocity is also reasonable to be used at high velocity measurement.
		2023 Vol. 44 (4): 591-597 [Abstract] ( 167 ) HTML (1 KB) PDF (21092 KB) ( 58 )

	598	Optimal Flow Characteristics and Timing Error of a Rotary Flow Diverter
		YANG Wan-li,WANG Xin-gen,CHEN Yu-jie,SHEN Yu-ming
		DOI: 10.3969/j.issn.1000-1158.2023.04.16
		The function expression of the flow characteristics of the rotary flow diverter was deduced. It can be seen from the expression that when the splitter plate of the diverter moves at a constant speed through the nozzle slot, the optimal flow characteristic curve with an approximately linear relationship is obtained. A flaw of the Biryukov curves was pointed out. It was also proposed that the essence of the flow diverter timing error Δt is the error caused by the installation asymmetry and the flow characteristic asymmetry, not the travel difference. The tow computational equations of the timing error were deduced, the equation in JJG 164—2000(flowmeter method) and the one in ISO4185 standard (static weighing method). A stepper motor drive system was designed, and experiments on the installation asymmetry of the diverter were carried out. The experimental results show that when the diverter splitter plate is triggered in advance, the timing error produces a negative deviation while lag trigger produces a positive deviation; and the greater the distance from the center point, the greater the absolute value of the timing error.
		2023 Vol. 44 (4): 598-603 [Abstract] ( 148 ) HTML (1 KB) PDF (49160 KB) ( 63 )

	604	Atomic Vapor Cell’s Relaxation Rate Measurement Based on Atomic Rabi Resonance
		MIN Ji-chi,JIN Shuang-hao,JIANG Wen-song,RU Ning,LUO Zai
		DOI: 10.3969/j.issn.1000-1158.2023.04.17
		The atomic vapor cell is a core component in quantum precision measurement instruments, and the atomic relaxation rate is one of the important parameters of the cell.For the measurement of atomic relaxation rate, a microwave cavity was designed by Comsol Multiphysics software, and the microwave propagation process in the atomic gas chamber was simulated, which verified the rationality of the microwave cavity design.A system for measuring the relaxation rate of the atomic vapor cell was built, and the line shape of the Rabi resonance was measured with a fast Fourier transform analyzer(FFT).The cell relaxation rate was obtained by processing the experimental data, and this method is more convenient and accurate than the theoretical calculation of atomic relaxation rates and does not require excessive experimental conditions.
		2023 Vol. 44 (4): 604-608 [Abstract] ( 154 ) HTML (1 KB) PDF (59434 KB) ( 65 )

	609	Target Tracking Method Based on Cross-channel Attention
		ZHANG Li-guo,GENG Xing-shuo,JIN Mei,ZHANG Yu-peng,ZHANG Sheng
		DOI: 10.3969/j.issn.1000-1158.2023.04.18
		Aiming at the problem that the tracking target is blocked or there are sensitive interferences around the target, which leads to the classification error of foreground background and the prediction error of boundary box, an anchor frame-free target tracking method based on cross-channel attention is proposed. Firstly, cross-channel attention is used to enhance the last three layers of output of feature extraction, and the correlation of all channel features is integrated by using the similarity of target in template features and search features, so as to selectively enhance the channel of target features. After that, feature fusion is carried out by weighted summation, and shallow feature fusion and deep feature fusion are used to improve classification accuracy and location accuracy. Finally, location attention is used to enhance the features of the classification feature map again to improve the accuracy of target location. Experimental results show that the proposed algorithm achieves 85.5% precision rate and 64.1% success rate on OTB100 dataset, and 70.5% precision rate and 56.0% success rate on UAV20L dataset.
		2023 Vol. 44 (4): 609-615 [Abstract] ( 144 ) HTML (1 KB) PDF (76632 KB) ( 60 )

	616	Measurement of the Mass Attenuation Coefficient of Medical Radiation Module by HXCF
		GUO Kai-yue,ZHAO Tian-qi,GUO Si-ming,JIANG Zheng,QIE Xiao-yu,YU Tao,WU Jin-jie
		DOI: 10.3969/j.issn.1000-1158.2023.04.19
		Mass attenuation coefficient is an important physical quantity in X-ray analysis,and it is the most commonly used radiation characterization parameter at present. The hard X-ray ground calibration device can provide “single energy and narrow beam” experimental conditions for the measurement of mass attenuation coefficient,and is an ideal device for the study of mass attenuation coefficient. The mass attenuation coefficients of two medical module materials,Poly tetra fluoroethylene(PTFE) and Polymethyl methacrylate(PMMA),were measured in the energy range of (40~80) keV with a hard X-ray ground calibration device. The measured mass attenuation coefficients were compared with the reference values in NIST database. The relative deviation between experimental value and theoretical value was analyzed. The results show that the variation trend of the mass attenuation coefficient curves of the two materials is consistent with the theoretical value. The maximum relative deviation between the measured values of PTFE and the theoretical values is 5.274%@47keV,and the maximum relative deviation between the measured values of PMMA and the theoretical values is 6.303%@51keV.
		2023 Vol. 44 (4): 616-621 [Abstract] ( 134 ) HTML (1 KB) PDF (58750 KB) ( 54 )

	622	An Adaptive Lorentz Peak Fitting Method Based on GA-NSVM to Identify Overlapping Oeaks of Infrared Spectrum Absorption
		LI Zhong-bing,PANG Wei,LIANG Hai-bo,JIANG Chuan-dong,DUAN Hong-ming,LUO Yi
		DOI: 10.3969/j.issn.1000-1158.2023.04.20
		A genetic algorithm-nonlinear support vector machine (GA-NSVM)-based adaptive Lorentz peak fitting method for infrared spectral overlapping peak identification is proposed. Based on the fundamental difference of the characteristic absorption line patterns of the elemental substance, the mixture spectrum is decomposed into multiple Lorentz single peaks, and the nonlinear support vector machine is used to perform multi-class screening on the multiple fitted single peaks, so as to determine absorption peaks for specific components. The feasibility of this method in the spectral identification and classification of highly similar molecular structures was demonstrated in the collected infrared spectrum data set of 400 alkane mixture samples. The experiment results show that the proposed method can effectively separate the infrared absorption peaks of methane, ethane, and propane in alkanes with good accuracy and robustness, and a stronger parameters interpretation ability. It can accelerate the application of spectral detection technology in the fields of biopharmaceuticals, food chemical industry, oil and gas exploration, etc., especially in analysis and applications containing homologous organic compounds.
		2023 Vol. 44 (4): 622-629 [Abstract] ( 139 ) HTML (1 KB) PDF (84472 KB) ( 60 )

	630	Combined Prediction Model of SO2 Concentration at Outlet of Absorber Based on VMD-IASO-ELM
		JIN Xiu-zhang,LI Yang-feng,YAO Ning
		DOI: 10.3969/j.issn.1000-1158.2023.04.21
		In order to improve the emission control level of SO2 pollutants in thermal power plants, a combined prediction model of SO2 concentration at outlet of absorber was proposed based on VMD-IASO-ELM. Firstly, the mechanism and correlation analysis were used to determine the initial correlation variables of SO2 concentration at outlet of absorber, and variational mode decomposition (VMD) algorithm was used to decompose it. The low-frequency components with large mutual information between the decomposition results and the output were retained. Then, the simple structure was established based on fast-learning extreme learning machine (ELM), and the improved atomic search optimization (IASO) based on hybrid strategy was used to optimize network parameters and improve the prediction accuracy. Finally, the error correction term was deduced from fuzzy rules to correct the prediction results of ELM model. Using historical data for simulation modeling, the results show that the model has high prediction accuracy and learning ability and can accurately track the change trend of SO2 concentration at the outlet of absorber.
		2023 Vol. 44 (4): 630-637 [Abstract] ( 151 ) HTML (1 KB) PDF (60040 KB) ( 46 )

	638	The Calibration Method and Uncertainty Evaluation for Cooking Fumes Monitor
		SHEN Shang-yi,ZHANG Guo-cheng,SI Chuan-hai,ZHANG Chun,Lü Chao1,WU Dan
		DOI: 10.3969/j.issn.1000-1158.2023.04.22
		Due to the efficiency and convenience,cooking fumes monitors has been widely used in environmental monitoring. However,it is urgent to establish a method of traceability for the instrument to ensure the accuracy of monitoring. The calibration method of cooking fumes monitors is established by using the self-built calibration device,and the measurement uncertainty is evaluated. The deviation of stability and uniformity of the concentration of cooking fumes monitors in the self-built calibration device is less than 5%,which provides a reliable detection condition for the instrument and its standard method. In addition,two typical operating conditions (flue gas flow rate: 4.6m/s,6.2m/s) of small and medium-sized dining lampblack treatment facilities are selected as test conditions. Two equipments are calibrated and tested using cooking oil fume concentration calibration device. After calibration, the relative error between the instrument measurement value and the standard method measurement value is less than 20%, meeting the requirements for online monitoring of cooking oil fume.
		2023 Vol. 44 (4): 638-644 [Abstract] ( 151 ) HTML (1 KB) PDF (29626 KB) ( 60 )

	645	Feature Extraction and Analysis of Organic Mixture Signal Based on Blind Source Separation
		HUANG Xiu,KANG Jia-cheng,WANG Qi,LI Yan-kun
		DOI: 10.3969/j.issn.1000-1158.2023.04.23
		A systematic study on blind source analysis of complex organic mixture system based on independent component analysis (ICA) was carried out. By establishing a reasonable number of independent components, the selection of the number of independent components was optimized by the root mean square error between the reconstructed signal of the separation signal and the original signal, and variance contribution rate of principal components.The following studies have been completed by integrating three ICA algorithms: (1) The source analysis of the mixed mass spectrum signals of various environmental organic pollutants including nitrobenzene, among which the independent components extracted by Kernel ICA have a high correlation with the actual source signals, and the average value (standard deviation) of the substance R is 0.8697 (0.10), which can meet the requirements of qualitative identification; (2) The extraction of characteristic component information in the ultraviolet spectrum signal of Compound Paracetamol and Amantadine Hydrochloride, Kernel ICA is the most effective algorithm for extracting the main components of drugs. The aboved research work provides theoretical support for the construction of the optimal blind source analysis model of organic matter system, and provides an effective means for the source analysis of organic pollutants in actual environmental samples and the extraction of effective components of drugs.
		2023 Vol. 44 (4): 645-652 [Abstract] ( 182 ) HTML (1 KB) PDF (99024 KB) ( 85 )

	653	Modification of Rapid Evaluation Method for PM2.5 Cutter by Internal Calibration Method
		LIU Jia-qi,ZHANG Guo-cheng,TIAN Ying,WU Dan,SHEN Shang-yi,JING Wen-jie,QU Xiao-hu,ZHANG Yan-wei
		DOI: 10.3969/j.issn.1000-1158.2023.04.24
		The rapid detection of PM2.5 cutter by using polydisperse particles can greatly improve the detection efficiency. It was found that the particle size measurement results of aerodynamics particle size spectrometer are occasionally offset (small). In order to overcome the influence of drift, the reference material of monodisperse microspheres was proposed to be added into the polydisperse particles. The drift of the capture efficiency curve can be corrected by the standard value of the particle size. This method was used to evaluate imported and domestic PM2.5 cutters, and the evaluation results were compared with the evaluation results of eight kinds of particle size monodisperse microspheres. This method not only made use of the high efficiency of aerodynamic particle size spectrometer method in PM2.5 cutter evaluation, but also effectively avoided the influence caused by offset, which has the role of improving the measurement reliability in the application of aerodynamic particle size spectrometer.
		2023 Vol. 44 (4): 653-656 [Abstract] ( 170 ) HTML (1 KB) PDF (31170 KB) ( 48 )

	657	Research of Blood Glucose Control State Detection Based on Percussion Entropy
		XIAO Ming-xia,LU Chang-hua,NA Ta,WANG Tao
		DOI: 10.3969/j.issn.1000-1158.2023.04.25
		Aiming at the limitations of existing models of blood glucose control state analysis, an algorithm of blood glucose control state analysis based on percussion entropy (PEn) was proposed.The human pulse wave and ECG signal were collected non-invasively. The amplitude characteristics of the pulse wave signal and the time interval characteristics of the R wave cycle of the ECG signal were extracted to form two time-synchronized numerical sequences. Compared the change trends of the two sequences, calculate the collision entropy of the pulse wave and the ECG signal, and finally detect the blood glucose control status. The results showed that the difference of PEn between healthy and well-controlled diabetic patients was p=0.014, while that between well-controlled and poorly-controlled diabetic patients was p=0.002.From the impact of HbA1c on the two indicators, the PEn index was 30.5% higher than the index of fEmax_RF.PEn can not only been used to reflect the prevalence of diabetes mellitus, but also showed good differences in glycemic control.
		2023 Vol. 44 (4): 657-663 [Abstract] ( 152 ) HTML (1 KB) PDF (119085 KB) ( 56 )

	664	The Measurement Uncertainty Evaluation of Linear Regression Fitting
		XIA Yu-guo,PENG You-zhi,LIU Zheng-hua,SONG Xiao,ZENG Zhuo
		DOI: 10.3969/j.issn.1000-1158.2023.04.26
		The measurement uncertainty of the least squares linear regression fitting results was evaluated by GUM method, and a general formula of standard uncertainty was proposed to estimate the influence of error of independent variable in coefficient matrix and dependent variable simultaneously. Firstly, the linear regression fitting model and least squares estimation results were described.Secondly, considering the influence of coefficient matrix, the general formulas for fitting parameters, fitting values, sensitivity coefficients on independent and dependent variables, and standard uncertainty were derived. At the same time, considering the correlation, a general formula for standard uncertainty after special treatment of variable correlation is given. Finally, the sensitivity of linear displacement sensor (without considering the correlation) and the additive multiplying constant of geodimeter (considering the correlation) were taken as examples to compare with the Monte Carlo method (MCM).The research results showed that the calculation results of the GUM method were basically consistent with the results of the MCM method.
		2023 Vol. 44 (4): 664-670 [Abstract] ( 247 ) HTML (1 KB) PDF (3808 KB) ( 328 )

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