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2023 Vol. 44, No. 11
Published: 2023-11-28
 
1639 Research on Attitude Adjustment Method of Suspension Coil in Joule Balance
GAN Wei,ZENG Tao,BAI Yang,LI Zheng-kun,WANG Yue
DOI: 10.3969/j.issn.1000-1158.2023.11.01
Alignment error will be introduced if the initial pose of the suspension coil is not ideal. The precision control of the horizontal position of the coil center can be realized with the help of a two-axis high-precision displacement platform. However, due to the coupling effect among the 3-link adjustment mechanisms of coil attitude adjustment, it is difficult to achieve accurate attitude adjustment. Based on the mathematical model between the initial pose and parasitic displacement of the suspension system of Joule balance, the absolute horizontal position of the coil was determined. The attitude control experiment was carried out near the absolute horizontal position of the coil, and the discrete state space model of the attitude control system of the suspension coil was obtained by using the recursive lLeast square method. On this basis, a model predictive control strategy based on state space was established to approximate adjust the attitude of the suspension coil to the absolute horizontal. The 3-link control accuracy was better than 0.25μm, and the attitude control accuracy was better than 1μrad.
2023 Vol. 44 (11): 1639-1645 [Abstract] ( 130 ) HTML (1 KB)  PDF (2031 KB)  ( 330 )
1646 Research on Hysteresis Nonlinearity Improvement of Piezoelectric Actuator Based on Charge Pump
ZHANG Lian-sheng,ZHANG Peng-cheng,HAO Shuang,HUANG Qiang-xian,CHENG Rong-jun,LI Hong-li
DOI: 10.3969/j.issn.1000-1158.2023.11.02
Piezoelectric actuator has been widely used in precision positioning, micro/nano measurement fields. However, hysteresis and nonlinear phenomena seriously affect its positioning accuracy and performance. Although the charge driving method can reduce most of the hysteresis, there is still obvious residual hysteresis, especially when the voltage range is large, and the hysteresis of piezoelectric actuator shows an increasing trend. Based on the analysis and calculation of residual hysteresis, a method to improve the residual hysteresis of charge pump driving method is proposed, and the derivation method of correction parameters are studied, to improves the hysteresis nonlinearity of classical charge pump drive. Through experiments, it is found that in the case of a drive voltage range of 0~100V and a drive frequency of 0.1~2Hz, the improved charge pump drive method can further reduce the hysteresis to less than 0.47%, which is about 83% lower, compared with the classical charge pump drive method of hysteresis of 2.79%. The proposed method has good application value in precision measurement and other fields.
2023 Vol. 44 (11): 1646-1651 [Abstract] ( 93 ) HTML (1 KB)  PDF (1336 KB)  ( 301 )
1652 Wavelength Measurement by Michelson Interferometry Based on Fractional Fourier Transform Signal Processing
JIANG Sheng,WU Jin-min,LU Ming-feng,WEI Hong-tao,FAN Jun-fang,ZHANG Feng,TAO Ran
DOI: 10.3969/j.issn.1000-1158.2023.11.03
The mathematical model of the fringe pattern obtained by Michelson interferometric measurement of wavelength is established, its linear frequency modulation signal (chirp signal) characteristics are revealed, and Michelsonss interferometric fringe processing based on the fractional Fourier transform signal processing method is proposed to realize the laser wavelength measurement. The experimental results show that the proposed wavelength measurement method is feasible. The average relative error of wavelength measurement is about 0.39% for lasers in the wavelength range of 400nm to 635nm. The average relative error in wavelength measurement is still less than 1% when the interferogram is contaminated by Gaussian white noise.
2023 Vol. 44 (11): 1652-1658 [Abstract] ( 103 ) HTML (1 KB)  PDF (11573 KB)  ( 56 )
1659 Underwater Target Detection Algorithm Based on Improved FCOS
CHEN Wei-dong,XIE Xiao-dong,CEN Qiang,CHEN Na-lan,ZHU Qi-guang
DOI: 10.3969/j.issn.1000-1158.2023.11.04
Propose an underwater target detection algorithm based on an improved fully convolutional one-stage object detection (FCOS). In response to problems such as high color cast, low contrast, dark color bias, and blurry distortion in underwater optical images that result in poor performance of existing target detection algorithms in underwater environments, the ordinary convolutions in the backbone network are replaced with deformable convolutions (DCN) for optimization, enhancing the algorithm's feature extraction capability in blurry underwater images. The feature fusion network and detection network of the improved network are enhanced through neural architecture search (NAS) to improve the utilization of features extracted by the backbone network. The CIoU Loss is adopted as the new loss function to improve the accuracy of coordinate regression. Experimental results show that the algorithm improves the detection accuracy by 1.8% and recall rate by 2.2% on the DUO dataset, with a detection speed of 53.4 frames /s, which is a 5.0% reduction compared to the previous version. The algorithm achieves high accuracy and meets the requirements of real-time detection.
2023 Vol. 44 (11): 1659-1666 [Abstract] ( 128 ) HTML (1 KB)  PDF (8677 KB)  ( 67 )
1667 Research on Image Super-Resolution Reconstruction Algorithm Based on FSRCNN Supplementary Module
CHEN Wei-rui,HOU Pei-guo
DOI: 10.3969/j.issn.1000-1158.2023.11.05
The activation function can increase the nonlinearity of the algorithm and improve the complexity of the algorithm in the super-resolution reconstruction algorithm. Using the ReLU activation function, the algorithm has the advantage of short training time, and in view of the problem that the negative value is zeroed through the ReLU activation function, resulting in the inactivation of some neurons, the inactivated part is re-added to the model through the rReLU function, and the method is named FSRCNN supplementary module. The results show that the peak signal-to-noise ratio of the supplementary module algorithm is 0.1dB higher than that of the original FSRCNN algorithm under the condition of magnification of 4, so the supplementary module can improve the performance of the model and enhance the extraction of information by the model.
2023 Vol. 44 (11): 1667-1672 [Abstract] ( 121 ) HTML (1 KB)  PDF (2396 KB)  ( 248 )
1673 Evaluation of Uncertainty in Measurement of Etallographic Microscope Distortion
YU Ze-li,FANG Yong-qiang,YANG Jun-hong,ZHANG Bing,ZHANG Yi-xin,ZHENG Yi,BI Ge-ping
DOI: 10.3969/j.issn.1000-1158.2023.11.06
Distortion can reflect the deviation between the actual image and the ideal image of a metallographic microscope, and is an important technical indicator for accurate and reliable performance of metallographic microscopes. According to the calibration standard "Evaluation and Representation of Measurement Uncertainty", the distortion measurement process of the metallographic microscope was studied, the mathematical model for the uncertainty evaluation of the distortion measurement results was established, the sources of uncertainty were comprehensively analyzed, and the uncertainty of the distortion measurement results of the metallographic microscope was evaluated.The results show that when the coverage factor k=2, the confidence level is 95%, under the condition of the total magnifications is 50×, 100×, 200×, 500× and 1000×, the relative distortion measurement results of the metallographic microscope is (0.5±0.4)%, (0.3±0.6)%, (1.3±0.4)%, (0.4±0.4)%, (0.9±0.1)%, respectively. The uncertainty of the measurement results mainly comes from the distortion measurement system and repeatability test.
2023 Vol. 44 (11): 1673-1679 [Abstract] ( 122 ) HTML (1 KB)  PDF (1589 KB)  ( 296 )
1680 Study on Interpolation Method of NTC Thermistor Thermometer in Body Temperature Range
CHEN Ze-chuan,PAN Jiang,CHEN Wei-xin,LI Ting,SUN Jian-ping,WANG Guang-yao,HU Jing,LI Jia-hao,WU Xiao-yang
DOI: 10.3969/j.issn.1000-1158.2023.11.07
In response to the urgent need to replace standard mercury thermometers under the Minamata Convention, a high-precision interpolation method for body temperature range and a feasibility study on its replacement were carried out using a negative temperature coefficient (NTC) thermistor thermomete with high stability and significant nonlinear characteristics. The study was conducted using national primary temperature standard instruments. The results show that the domestic NTC thermistor thermometers, which are used to replace the mercury thermometer, can obtain annual stability better than 4 mK at the gallium melting point. The optimal combinations of calibration points for the Steinhart-Hart and Hoge-1 equations (3-point interpolation) are 35℃, 41℃, 45℃. The Hoge-1 equation shows better interpolation characteristics with a maximum fitting residual of 1.2mK, which shows feasibility of alternative. The results will provide technical support for the development of NTC thermistor-based standard thermometers and promote the replacement of standard mercury thermometers.
2023 Vol. 44 (11): 1680-1686 [Abstract] ( 124 ) HTML (1 KB)  PDF (2035 KB)  ( 355 )
1687 Development of the Gold-Platinum Thermocouple Calibration Installation
ZHENG Wei,TANG Lei,XIANG Ming-dong
DOI: 10.3969/j.issn.1000-1158.2023.11.08
The gold-platinum thermocouple is one of the most accurate thermocouples available. The development of calibration installation for the high-precision gold versus platinum (Au/Pt) thermocouple and process and method of calibrating thermocouple are described. The calibration installation constructed with the temperature fixed point facilities, a specified annealing furnace and a low electric motive force (EMF) measurement is fully capable to calibrate thermocouple and a new method is proposed for evaluating the uncertainty components caused by thermoelectric inhomogeneity. The measurement reproducibility of calibration installation is up to 7mK and the calibration uncertainty is 0.03℃(k=2), which is sufficient for calibrating Au/Pt thermocouples.
2023 Vol. 44 (11): 1687-1691 [Abstract] ( 115 ) HTML (1 KB)  PDF (1293 KB)  ( 244 )
1692 An Image Reconstruction Method of ECT Based on Improved Coot Optimization Algorithm
ZHANG Li-feng,CHEN Da
DOI: 10.3969/j.issn.1000-1158.2023.11.09
Electrical capacitance tomography (ECT) technology has serious pathologies in solving the problem of image reconstruction. In order to improve the accuracy of image reconstruction, an ECT image reconstruction algorithm based on improved coot optimization algorithm is proposed. Aiming at the problems of poor stability and easy to fall into local optimization caused by the random generation of initial population in the standard coot optimization algorithm (COA), the good point set method and sine and cosine optimization method are introduced, and the ART reconstruction algorithm is combined to improve the target function according to the characteristics of ECT imaging. Finally, simulation and static experiments are carried out, and compared with linear back projection (LBP) algorithm, Landweber algorithm and ART algorithm, the results show that this method can effectively improve the accuracy of image reconstruction.
2023 Vol. 44 (11): 1692-1698 [Abstract] ( 100 ) HTML (1 KB)  PDF (7451 KB)  ( 58 )
1699 Analysis of Effect of Acceleration Sensor on Vibration Compensation of Gravimeter
MA De-kai,LI Chun-jian,FENG Jin-yang,FAN feng,YAO Jia-min,WANG Qi-yu,HU Ruo
DOI: 10.3969/j.issn.1000-1158.2023.11.10
In order to analyze the compensation effect of accelerometer on gravimeter, based on the NIM-3C absolute gravimeter, a platform gravimetric experiment platform was built, the laser vibrometer output signal was used as the standard signal, and the vibration collection performance of three different types of acceleration sensors, MSA1000A-02, 991B, and INV9832-50, in the platform based gravity measurement environment was calibrated through experiments. The experimental results show, in order to ensure that the gravity measurement uncertainty under this condition is smaller than several milligal, the measurement error of the acceleration sensor should be limited to within several hundred μGal. The extreme difference between the quadratic term fit coefficient of the vibration (standard signal) measured by the MSA1000A-02 sensor and the laser vibrometer is 2.94 μGal (1 μGal=1×10-8m/s2) under the platform gravity measurement condition, which meets the uncertainty and bandwidth requirements of this condition.
2023 Vol. 44 (11): 1699-1705 [Abstract] ( 87 ) HTML (1 KB)  PDF (2721 KB)  ( 298 )
1706 Testing Technology of Swing Vehicle Instrument Based on 6 Degree of Freedom Trajectory
HAN Zhi,CHEN Chun-Lei,CHENG Zhao-Yang,ZHAO Zi-Shen,LIU Kai
DOI: 10.3969/j.issn.1000-1158.2023.11.11
The test method of the existing swing vehicle was single, which was difficult to meet the requirements of actual working conditions. Based on the 6 degree of freedom platform, the trajectory of its composite motion is used to measure the amplitude of the composite vibration angle through data fusion with the gyroscope sensor. In order to improve the solution accuracy of the wobble vehicle, the linear angular compound vibration was quantified and the amplitude of vibration angle was measured by gyroscope, and the inclination effect of the single acceleration sensor was corrected under the compound vibration, and the expanded uncertainty evaluation was conducted on the reference frequency points after the fusion solution. The results showed that the relative expanded uncertainties of the linear and angular vibrations of the entire testing system after the fusion of the data of the gyroscope and the wobble instrument were 0.36% and 0.08%, respectively, expanding the standard testing conditions of the wobble instrument.
2023 Vol. 44 (11): 1706-1712 [Abstract] ( 93 ) HTML (1 KB)  PDF (4331 KB)  ( 118 )
1713 A State-Based Filtered-x Recursive Least Squares Algorithm
CHU Yi-jing,ZHAO Yue-zhe,NIU Feng,Chen Ming-yang
DOI: 10.3969/j.issn.1000-1158.2023.11.12
The filtered-x type algorithms have been widely used in active noise control systems, where an accurate modeling of the secondary path is usually required. However, stability problems are frequently observed when the secondary path is not well estimated. A Fx recursive least squares algorithm has been proposed, where a random walk model for the state equation of the controller has been employed to improve the robustness of the system. The mean difference equation is derived by using the Abelian integral and Price theorem with Gaussian input. A conservative convergence condition of the proposed algorithm in the mean sense is thus derived from the theoretical analysis, which could provide guidance for algorithm design. Simulations are conducted to show that the proposed algorithm considerably outperforms conventional Fx-type algorithms in stability and convergence capability.
2023 Vol. 44 (11): 1713-1718 [Abstract] ( 128 ) HTML (1 KB)  PDF (4952 KB)  ( 196 )
1719 Joint SOC and SOH Estimation for Lithium Batteries Based on Adaptive H2/H∞ Filtering
WU Zhong-qiang,CHEN Hai-jia
DOI: 10.3969/j.issn.1000-1158.2023.11.13
Accurate and real-time estimation of a batterys state of charge (SOC) and state of health (SOH) is a key task of modern battery management systems.The SOC and SOH of lithium batteries can be estimated jointly by an adaptive H2/H∞ filter. This method is based on the second-order RC equivalent circuit model of lithium battery, and AFFRLS method is used to identify the model parameters of lithium battery online.Using H2/H∞ filter to estimate SOC of lithium battery, AFFRLS identification and H2/H∞ filter are alternated to obtain an adaptive H2/H∞ filter.SOH is estimated according to the internal resistance identified by AFFRLS, and the joint estimation of SOC and SOH of lithium battery is realized.The experimental results show that the adaptive H2/H∞ filtering algorithm has high estimation accuracy and strong robustness, and the average estimation error of SOC and SOH of the battery is always within 0.19%, which has higher estimation accuracy and stability than EKF and H∞ filtering algorithm.
2023 Vol. 44 (11): 1719-1727 [Abstract] ( 99 ) HTML (1 KB)  PDF (2199 KB)  ( 113 )
1728 Research on Time Domain Measurement Method of Broadband Grounded Coplanar Waveguides
ZHU Jiang-miao,WAN Zhao-tong,ZHAO Ke-jia,WANG Peng-fei,ZHANG Meng-meng
DOI: 10.3969/j.issn.1000-1158.2023.11.14
The broadband grounded coplanar waveguide (GCPW) is the core component for calibrating oscilloscope broadband probes. To accurately measure the bandwidth of the oscilloscope probe, obtaining the transmission characteristics of the broadband GCPW becomes the key to achieving high-precision calibration. A GCPW time-domain twice measurement system is constructed based on femtosecond laser excitation picosecond electric pulse technology in the measuring principle of time-domain automatic network analyzer(TDANA). This involves taking two measurements in the system to solve the impulse response of the broadband GCPW(twice measurement method), thereby the frequency domain bandwidth can be obtained. The GCPW is designed with a post-wall structure (vias placed along the signal trace), and the processed sample is measured by the twice measurement method. In this way, the 3dB bandwidth of our sample reaches 54.2GHz, which greatly agrees with the simulation result. The calibrated broadband GCPW can be used as a standard device for calibrating broadband probes, and its measured results can be effectively traced to the national benchmark for pulse waveform parameters.
2023 Vol. 44 (11): 1728-1734 [Abstract] ( 127 ) HTML (1 KB)  PDF (9186 KB)  ( 185 )
1735 Traceability and Measurement Method for On-wafer Capacitance Test System
DING Chen,QIAO Yu-e,LIU Yan,ZHAI Yu-wei,WU Ai-hua
DOI: 10.3969/j.issn.1000-1158.2023.11.15
A traceability and measurement method was proposed in order to solve the problem that the capacitance parameter of on-wafer traceability and inaccurate measurement. The measurement results were connected with the four-terminal par capacitor standard by the on chip straight line to realize the traceability. Adopting the quantitative research of interference loop, corrected the influence of the probe system and cable, and accurated measurement of on wafer capacitance. The measurement accuracy of the metering levels test system improved 0.08% by this method.
2023 Vol. 44 (11): 1735-1739 [Abstract] ( 102 ) HTML (1 KB)  PDF (3124 KB)  ( 50 )
1740 Classification and Recognition Algorithm of Motion Imagination Based on Improved Transfer Learning
DU Yi-hao,CHANG Chao-qun,DU Zheng,ZHANG Yan-fu,CAO Tian-fu,FAN Qiang,XIE Ping
DOI: 10.3969/j.issn.1000-1158.2023.11.16
The use of transfer learning algorithms to improve the accuracy of classification recognition is a hot research problem in the application of motion imagination brain-computer interface. Traditional model algorithms for sample transfer and feature transfer do not achieve ideal transfer results when the sample size is small or there is a significant difference between the source domain data and the target domain data. The motion imagery classification algorithm based on Euclidean alignment (EA) and improved jointly class centroid matching and local manifold self-learning (CMMS) migration learning organically combines the advantages of sample migration and feature migration to further improve the classification accuracy while considering the sample itself. Firstly, the samples are subjected to EA in the source and target domains to reduce the differences in data distribution between the source and target domains. Secondly, the CMMS method is improved based on minimizing the maximum mean difference (MMD) to filter the data in the source domain and again reduce the differences in distribution between the samples in the source and target domains. Finally, the method is applied to the BCI competition dataset for offline testing and online experiments. The experimental results show that compared with SVM, JDA, BDA, EasyTL, GFK, and CMMS, the recognition accuracy of the migration learning model is improved by 14.38%, 8.5%, 5.8%, 10.4%, 11.8%, and 5.7%, respectively.
2023 Vol. 44 (11): 1740-1748 [Abstract] ( 126 ) HTML (1 KB)  PDF (2566 KB)  ( 502 )
1749 The Measurement Uncertainty Evaluation of AC Common Mode Rejection Ratio of Data Acquisition Aystems by Using Averaging Method
LIANG Zhi-guo,FENG Xiu-juan
DOI: 10.3969/j.issn.1000-1158.2023.11.17
It is described that the uncertainty of evaluation results of AC common mode rejection ratio (CMRR) of data acquisition systems (DAS) by using averaging methods, the interference is calculated by using the means of the absolute sampling data, and the base noise is also calculated as the same method. Then the base noise is cancelled from interference by using direct picking out, and the courses of analysis and evaluation of uncertainty is discussed. Some error sources of CMRR evaluation are discussed, including the signal errors, the gain errors of DAS, the amplitude measuring errors of DAS, the resolution of DAS, the repeatability errors, and the others. The uncertainty model of CMRR of DAS is given out. Combine with an example of experiment, the uncertainty evaluation results of CMRR by using the proposed method is presented.
2023 Vol. 44 (11): 1749-1754 [Abstract] ( 126 ) HTML (1 KB)  PDF (606 KB)  ( 55 )
1755 Traceability Research of Airborne Particle Number Concentration in Micrometer-scale
GUO Li-xu,LIU Jun-jie,LIU Yue,YE Jing,REN Jun
DOI: 10.3969/j.issn.1000-1158.2023.11.18
To study the traceability technology of the number concentration of airborne particles in micrometer range, an inkjet aerosol generator (NIM-IJAG) is developed and its performance is verified. The particle size and number concentration of obtained solid particles by NIM-IJAG are closely related to the nozzle aperture, solute density, solution mass concentration, output parameters of electrical controller, clean air flow volume and other parameters. On the basis of accurately obtaining the droplet size, the effective control of the particle size of solid particles can be achieved by changing the solution concentration, the number concentration of solid particles could be effectively controlled by adjusting the voltage frequency applied on the nozzle. Through experimental verification, NIM-IJAG can produce 1~20μm monodisperse solid particle samples with number concentration in 0~30/cm3, which can trace to the national metrology standard.
2023 Vol. 44 (11): 1755-1762 [Abstract] ( 105 ) HTML (1 KB)  PDF (4073 KB)  ( 335 )
1763 Research on Calibration Method for Aerosol Diluter Based on Quantitative Generator Technology
HUANG Zhi-huang,LIU Jun-jie,XIAO Ji,LUO Xin-zheng,LIU Yue
DOI: 10.3969/j.issn.1000-1158.2023.11.19
For the purpose of decreasing the calibration uncertainty for aerosol diluter in traditional calibration method, and thus increasing results reliability, an aerosol diluter calibration method based on quantitative generator technology was proposed. The theoretical formula of aerosol quantitative generation technology was deducted firstly, an aerosol diluter calibration set-up with accurate and traceable chain was developed subsequently. And finally,the performance of the calibration device was verified and uncertainty analysis was conducted.The experimental results showed that the calibration device and method can achieve calibration of aerosol diluters within the dilution range of 1~300, with an uncertainty of 3.8%(k=2).
2023 Vol. 44 (11): 1763-1769 [Abstract] ( 116 ) HTML (1 KB)  PDF (1507 KB)  ( 152 )
1770 Surface Plasmon Resonance and its Application in Absolute Quantification of Active Protein Concentration
LUO Shi-wen,WU Li-qing,YANG Bin,LIU Ya-hui
DOI: 10.3969/j.issn.1000-1158.2023.11.20
Surface plasmon resonance (SPR) is a physical phenomenon observed when sparse and dense electron oscillations occur on a metal surface upon interaction with an incident electromagnetic wave.The analysis of the resonance angle during SPR provides valuable insights into intermolecular interactions.SPR-based calibration free concentration analysis (CFCA) enables the absolute measurement of protein activity concentration by quantifying the diffusion binding rate between a protein and its receptor or antibody under controlled mass-transfer-restricted conditions, eliminating the requirement for reference material, which is a technique for the absolute measurement of protein activity concentration. By reviewing the principle of SPR technology for the absolute quantification of protein activity concentration and its applications in various fields, the advantages and current issues of this technique are discussed, the future development direction of this technology and its main applications in protein quantification are also prospected.
2023 Vol. 44 (11): 1770-1775 [Abstract] ( 85 ) HTML (1 KB)  PDF (1429 KB)  ( 248 )
1776 Measurement Method of Tritium Concentration in Environmental Water Using a Liquid Scintillation Counter and Its Quality Control
HU Chong-qing,ZHAO Chao,LIU Jia-yu
DOI: 10.3969/j.issn.1000-1158.2023.11.21
Taking an ultra-low background liquid scintillation counter LSC-LB7 as an example, the experimental parameters and measurement methods for measuring tritium activity concentration in environmental water were studied and optimized.The optimized experimental parameters such as dark treatment time and counting window were summarized, which can effectively decrease the detection limit of tritium measurement of water samples by this liquid scintillation counter. The optimized measurements were compared to those with unoptimized parameters, the results showed that biggest relative deviation of 33.87% between the two methods, and that the optimized method was able to reduce the uncertainty of the tritium concentration in water by 50%. With the aim of quenching calibration using the liquid scintillation counter to measure tritium activity concentrations in environmental, a series of self-made standard sources with different degrees of quenching and a consistent tritium activity concentration was counted in a sequence by optimized measuring method, and a quenching calibration curve was created. When the quenching calibration curve was used to measure the environmental water samples and compared with the commercially available standard sources for quenching, it was observed that the actual values were different and the relative deviation is about 11%. Finally, based on the optimized liquid scintillation measurement method and the quenching calibration curve of the self-made standard source, the activity concentration of tritium in the environmental water sample was determined to be (12.21±2.08)Bq/L,k=2.
2023 Vol. 44 (11): 1776-1782 [Abstract] ( 101 ) HTML (1 KB)  PDF (1893 KB)  ( 213 )
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