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2022 Vol. 43, No. 3 Published: 2022-03-28

	293	Development of A New Method for Millimeter-waveintrinsic On-wafer Measurements
		WANG Yi-bang,WU Ai-hua,HUO Ye,LIANG Fa-guo,LUAN Peng,LIU Chen,DU Jing
		DOI: 10.3969/j.issn.1000-1158.2022.03.01
		To proposes accurate method for millimeter-wave devices intrinsicscatter-parameters. For millimeter-wave circuit design, accurate simulation result is required. For this reason, an accurate measurement of de-embedding is a key technique for device characterization, and is also important. In this work, a new model based on conventional open-short de-embedding method and corresponding solutionalgorithm are proposed. By adding transmission line with open and short standards to gain approximate ideal open and short, and at the same time, consummate the model with crosstalk which grows larger with increasing frequency.Considering the complex solution with crosstalk, the new model could eliminate the crosstalk influence on device under test avoiding knowing it. Calibration kits and device under test were also fabricated and measured. 110GHz Passive device was measured subject to both new method here and second tier crosstalk calibrations proposed by NIST. Measurement results demonstrate that new method is capable of eliminating the cross-talk and PAD more accurately with an improvement S;21 magnitude of 1.3dB, and show a promising result with NIST. A serial of active pHEMT test results also showed that, the new method was more accurate at device maxgain.
		2022 Vol. 43 (3): 293-298 [Abstract] ( 247 ) HTML (1 KB) PDF (2325 KB) ( 262 )

	299	Research for Calibration Comparison Method of Passive Deviceson-wafer Scattering Parameters
		HUO Ye,WU Ai-hua,WANG Yi-bang,LUAN Peng,LIU Chen,LIANG Fa-guo,SUN Jing,ZHANG Li-fei,HU Hai-long
		DOI: 10.3969/j.issn.1000-1158.2022.03.02
		In order to solve the problem of deviation in the measurement results of on-wafer scattering parameters of passive devices due to different calibration methods, by taking the multi-line TRL calibration method with high accuracy as the reference benchmark, the differences between SOLT and LRRM calibration methods error terms are compared. The cascading relation of two port error terms is fully considered, the mathematical model of error term difference is derived, and the maximum deviation on-wafer scattering parameters of the passive devices are calculated by parameter conversion. The experimental analysis is carried out in the frequency range of 100MHz～67GHz. Compared with foreign calibration comparison methods, the linear amplitude deviation of the four scattering parameters of the same calibration method is ≤0.01. The research results show that the mentioned method can judge whether the test results of on-chip scattering parameters of passive devices are real and effective, and guide the selection of appropriate calibration methods during the test.
		2022 Vol. 43 (3): 299-305 [Abstract] ( 222 ) HTML (1 KB) PDF (1364 KB) ( 134 )

	306	Bounds on Least-Squares Four-Parameter Sine-Fit Errors due to 8bit Quantization
		LIANG Zhi-guo
		DOI: 10.3969/j.issn.1000-1158.2022.03.03
		Aiming at the influence of the quantization error on the four-parameter sinusoidal fitting error, the fitting error bounds were searched on the five parameters of effective bits, amplitude, frequency, initial phase and DC component.The selected condition variables were amplitude, the number of cycles of the waveform contained in the sequence, the initial phase, the DC component and the number of sequence data points.The error boundary search was carried out in a two-condition combination styles, and the error curves of the above five parameters were gained with each condition, including both the upper and the lower error bounds.The result can be used to estimate the error and uncertainty of the fitting parameters, or to construct the measurement conditions under the hoping fitting error and uncertainty.
		2022 Vol. 43 (3): 306-317 [Abstract] ( 215 ) HTML (1 KB) PDF (9691 KB) ( 91 )

	318	Research on Stochastic Resonance Phenomenon of Fractional Bistable System and FPGA Implementation
		ZHU Zuo,ZHENG Yong-jun,LUO Zai
		DOI: 10.3969/j.issn.1000-1158.2022.03.04
		The fractional order is more concise and accurate for the description of complex systems with memory dependence and spatial correlation, compared with the integer order calculus. It is observed that the damping has power-law attenuation characteristics, so a reasonable autocorrelation damping kernel function is selected. Combining the theory of fractional calculus and Langevin equation, the fractional Langevin equation can be derived. Then, a FPGA implementation method of fractional bistable stochastic resonance system is proposed based on this theory. Finally, a simulation experiment is performed to verify whether the system can generate stochastic resonance by changing the order of the fractional order. The results show that the system can generate stochastic with an appropriate fractional order, which can effectively extract the weak signal submerged by noise. And there is an optimal fractional order that maximizes the useful signal output gain.
		2022 Vol. 43 (3): 318-324 [Abstract] ( 237 ) HTML (1 KB) PDF (2569 KB) ( 267 )

	325	Large Scene Segmentation of Outdoor Laser Point Cloud Based on Fusion and Registration
		XU Peng,XU Fang-yong,CHEN Hui
		DOI: 10.3969/j.issn.1000-1158.2022.03.05
		Aiming at the problem caused by the sparseness of outdoor laser point cloud scenes for semantic segmentation, a point cloud segmentation method based on deep learning is proposed. First, the laser point cloud scenes collected from five perspectives are processed, and parts of buildings with higher overlapping areas are selected in turn, and each group is registered by SAC-IA and ICP-based point cloud automatic registration methods. In order to construct a large outdoor scene with relatively uniform point cloud density, the public data set Semantic3D is used to train an outdoor point cloud segmentation model based on PointNet++, and the algorithm effect is verified on the test set. Finally, this model is used to segment the outdoor scene that has been constructed scenes and experimental results prove that point cloud scenes with multi-view registration can solve the problem of non-uniform sampling of point cloud scenes, so that the deep segmentation-based semantic segmentation model has a better recognition effect.
		2022 Vol. 43 (3): 325-330 [Abstract] ( 212 ) HTML (1 KB) PDF (4410 KB) ( 273 )

	331	Research on Correction of Fixation Point of Corneal-reflection-based Eye Tracking System
		HU Kai,MU Ping-an,HUANG Shi-long
		DOI: 10.3969/j.issn.1000-1158.2022.03.06
		In order to improve the accuracy of the system. The screen is divided into 6 rows and 8 columns, a total of 48 areas. Calibration points are set in the center of each area, and the tester looks at each calibration point in turn to calculate the 48 errors. The errors are decomposed into X-axis and Y-axis errors, and then the X-axis and Y-axis errors are used as calibration values and are interpolated to obtain the X-axis and Y-axis calibration values for any position within the entire screen. At last, X-axis and Y-axis calibration values are used to correct the X-axis and Y-axis coordinates of fixation point. Compared with the current better calibration method, the X-axis error is reduced by 35.8%, and the Y-axis error is reduced by 53.3%. The correction effect of this correction method is significantly improved, which can effectively improve the accuracy of eye tracking.
		2022 Vol. 43 (3): 331-337 [Abstract] ( 191 ) HTML (1 KB) PDF (2077 KB) ( 553 )

	338	Standard Dynamic Glare Light Source Design Method Based on Threshold Increment
		QIAO Wei-dong,ZHANG Heng,WANG Jia-ming,LI Yi
		DOI: 10.3969/j.issn.1000-1158.2022.03.07
		Aiming at the problem of inconsistent measurement standards faced by current glare measuring devices, a standard dynamic glare source design method based on threshold increments (TI) is proposed, and a glare measuring instrument calibration system is established. The structure of the standard dynamic glare light source is determined according to the measurement requirements of the threshold increment. In the process of glare measurement, the layout of the glare source is planned and the luminescence of the glare source area is determined under the premise that the position index and solid angle in the laboratory environment and the real street lighting environment are equal respectively. Simulation is performed for the same glare value in different scenes and different glare values in different scenes with a frequency of up to 24Hz to match the glare situation in various environments. The experimental results show that the standard dynamic glare source covers 8.0%~26.7%, and its flicker frequency can be adjusted up to 24 Hz, and the extended uncertainty of simulated glare is 1.3%, which can meet the calibration requirements of various glare measuring instruments.
		2022 Vol. 43 (3): 338-345 [Abstract] ( 223 ) HTML (1 KB) PDF (2960 KB) ( 381 )

	346	Real-world Image Dehazing Method of MAGNet Fusing Guided Filtering
		SANG Yu,SHEN Hong-qian,ZHANG Shi-hui,LU Jia-qi,ZUO Dong-xu,NIU Jing-chun
		DOI: 10.3969/j.issn.1000-1158.2022.03.08
		In order to improve the accuracy and applicable scope of the single image dehazing method, a real-world image dehazing method combining multiple attention grid network(MAGNet) and guided filtering is proposed. Firstly, according to the distribution characteristics and imaging principles of haze in real-world images, the multi-attention residual dense block is designed to effectively extract haze-related features in real-world images and the risk of gradient disappearance is reduced. Secondly, the end-to-end convolutional neural network based on the designed multi-attention residual dense block is constructed to remove haze from hazy images. Finally, the guided filtering is introduced into the dehazing problem to enhance the visual effect of dehazing images. The experimental results show that compared with the existing representative image dehazing methods, the proposed method can not only remove haze from real-world images, but also effectively remove haze from synthetic images, and the visual effect of dehazing image is better.
		2022 Vol. 43 (3): 346-354 [Abstract] ( 214 ) HTML (1 KB) PDF (6964 KB) ( 87 )

	355	Weak Signal Measurement in Thermoreflectance Temperature Testing Based on Stochastic Resonance
		ZHAI Yu-wei,LIU Yan,LI Hao,WU Ai-hua
		DOI: 10.3969/j.issn.1000-1158.2022.03.09
		To eliminate the impact of relative drift between DUT (device under test) and test instruments on thermoreflectance thermography, the image registration algorithm is studied, cooperated with a piezoelectric three axis nano-scale position stage, real time correction of drift is realized. Sub-pixel image registration algorithm is realized by Fourier transform, convolution in frequency domain and sinc function approximation, it can calculate the relative drift in real time; a test setup for thermoreflectance thermography is build, the position of the DUT is adjusted in real time by the three axis nano-scale position stage; the results show that, when the temperature of DUT rises from 20℃ to 50℃, there is an obvious displacement in the horizontal direction of the DUT, and this displacement can be correction by the test setup. A typical GaN HEMTs device is tested, the results are consistent with those measured by foreign testing institutions, and the image registration method is proved to be effective.
		2022 Vol. 43 (3): 355-359 [Abstract] ( 233 ) HTML (1 KB) PDF (4976 KB) ( 206 )

	360	Low-power and Mono Gas Ultrasonic Flowmeter Based on Dynamic Variable Threshold
		JIANG Zhen,XU Ke-jun,MA Jie,ZHANG Lun,XU Hao-ran
		DOI: 10.3969/j.issn.1000-1158.2022.03.10
		To overcome the shortcomings of pressure loss and the need for regular calibration with gas turbine flowmeter, a mono-channel gas ultrasonic flowmeter with high-pressure resistance and low power consumption is developed.In order to solve the poor quality of the echo signal caused by the impedance mismatch of the transducer, the features of the echo signal are analyzed.A digital signal processing method based on dynamic variable threshold and zero-crossing detection is proposed to accurately locate the feature point of the echo signal.A low-power gas ultrasonic flow transmitter with STM32 as the core has been developed, and a new excitation method is designed,which can not only prevent the two-way outputs of the MOSFET circuit from being turned on at the same time, but also save the excitation power consumption.The combination of pulse cumulative upload and optimal pulse frequency division reduces the pulse upload error.The gas flow calibration experiment results show that: the developed low-power mono gas ultrasonic flowmeter meets the requirements of the indicators of level 1 accuracy, and the range ratio is 1:21.
		2022 Vol. 43 (3): 360-369 [Abstract] ( 212 ) HTML (1 KB) PDF (3352 KB) ( 570 )

	370	Effect of Constant Current Source on Measurement Uncertainty of Near Infrared Spectrum Sensor
		FANG Li-de,XU Xiao-xiao,ZHAO Ji-xun,WEI Zi-hui
		DOI: 10.3969/j.issn.1000-1158.2022.03.11
		The stability of near-infrared (NIR) light source influences the reliability of NIR technology. Improving the stability of NIR power supply can improve the application of NIR technology in gas-liquid two-phase flow in laboratory. According to the experiment, the precise constant current source is used to power the NIR probe, which makes the NIR light source more stable and the output voltage more stable and reliable. The experiment shows that the range of output voltage is about 0.12 and the standard deviation is not more than 0.00838 when using high precision constant current source for power supply. While the range of output voltage obtained from ordinary power supply is about 0.16, and the standard deviation is no more than 0.02193.
		2022 Vol. 43 (3): 370-377 [Abstract] ( 206 ) HTML (1 KB) PDF (2207 KB) ( 185 )

	378	Mobile Reference Instrument for Online Measurement of Road Vehicle Speed Based on Multi-target 3D Tracking Radar
		DU Lei,SUN Qiao,BAI Jie,XU Tian-qi,HE Guo-quan
		DOI: 10.3969/j.issn.1000-1158.2022.03.12
		To promote the application of the online verification method in the field verification of vehicle speed measuring devices, a mobile reference instrument for online measurement of road vehicle speed based on multi-target 3D tracking radar is developed. The design requirement of the mobile reference instrument is firstly introduced. Then the working principles of speed, distance and angle measurement used in the reference instrument are analyzed, and the traceability method of speed measurement and uncertainty evaluation of speed measurement error of the reference instrument are described. Finally, the full-range simulated calibration tests in the laboratory and the large samples field comparison tests in actual traffic are carried out. The results show that the speed measurement errors of the mobile reference instrument are within ±0.5km/h at the speed value in the range of 10～100km/h and ±0.5% at the speed value in the range of 100～300km/h, and the accuracy rate of lane measurement is 100%.
		2022 Vol. 43 (3): 378-385 [Abstract] ( 207 ) HTML (1 KB) PDF (2115 KB) ( 222 )

	386	Fault Diagnosis of Rolling Bearings Based on Migration of Characteristic Parameters
		TANG Bo,CHEN Shen-shen,GUO Bi-ben,HAO Jia-qi
		DOI: 10.3969/j.issn.1000-1158.2022.03.13
		Aiming at the problem that rolling bearings under variable operating conditions cannot obtain a large number of labeled sample data and the low recognition rate of traditional deep learning diagnostic methods, a convolutional neural network rolling bearing fault diagnosis method based on transfer learning is proposed. First, the short-time Fourier transform is used to process the vibration signal of the rolling bearing to obtain the source domain and target domain sample sets; second, the source domain samples are used to pre-train the convolutional neural network model; finally, the target domain samples are used to fine-tune the convolutional neural network model to implement the rolling bearing troubleshooting.Two different rolling bearing vibration data are used to carry out migration fault diagnosis experiments.The experimental results show that: compared with the fault diagnosis method of convolutional neural network, the fault diagnosis recognition rate of convolutional neural network based on transfer learning is increased by 7%.
		2022 Vol. 43 (3): 386-391 [Abstract] ( 214 ) HTML (1 KB) PDF (2815 KB) ( 291 )

	392	Stability and Stabilization for Uncertain Fuzzy System with State Quantization Based on Sample-data Control
		ZHAO Zhi-wei,YANG Liu,XIE Li-dian,GE Chao
		DOI: 10.3969/j.issn.1000-1158.2022.03.14
		The stability and stabilization problems of the T-S fuzzy system with uncertainty and state quantization were studied. Considering that fuzzy membership functions (FMFs) are the main characteristic of T-S fuzzy model, if the information about FMFs is not added, it will be conservative. So, a novel Lyapunov-Krasovskii functional (LKF) which contained not only the information of state variables but also FMFs was constructed. Besides, the states on both sides of the sampling interval were incorporated into LKF. When deriving LKF, the product terms which consisted of derivative of FMFs and LKF coefficient were involved. And the product terms were discussed to ensure their negative definition. Later, enough stability conditions were expressed in the form of linear matrix inequalities (LMIs). The maximum sampling intervals and controller parameters were solved by MATLAB toolbox with the optimal parameters. Finally, a numerical example was simulated, and the maximum sampling interval for the T-S fuzzy inverted pendulum system was increased to 0.040s.
		2022 Vol. 43 (3): 392-398 [Abstract] ( 204 ) HTML (1 KB) PDF (706 KB) ( 133 )

	399	Technology of Arctangent Demodulation of Laser Heterodyne Interferometer Based on FPGA
		KE Wei,FENG Xiu-juan,YANG Ping,HE Long-biao,XING Guang-zhen,WANG Min
		DOI: 10.3969/j.issn.1000-1158.2022.03.15
		In order to eliminate the limitations of Doppler signal software demodulation in high-frequency acoustic applications,a digital hardware signal demodulation approach based on FPGA is proposed.It contains a high-speed ADC acquisition system based on AD9467 to implement the Nyquist sampling or band-pass sampling of the original Doppler signal.The digital signal processing system based on Xilinx Zynq-7000 SoC is designed to generate the I&Q baseband signal pair,which is obtained by mixing of DDS synthesized reference signal with Doppler signal and the following low-pass filtering.The CORDIC algorithm and phase unwrapping algorithm are used to demodulate the I&Q baseband signal pair and the real-time demodulation of Doppler signals is initially realized.Numerical simulation in the frequency range from 50kHz to 500kHz and the preliminary experimental results in the frequency range from 50kHz to 300kHz demonstrate the validation of the demodulation method and system.
		2022 Vol. 43 (3): 399-404 [Abstract] ( 258 ) HTML (1 KB) PDF (2121 KB) ( 504 )

	405	Research on a Time-frequency Measurement Algorithm for Underwater Acoustic Velocity
		BAO Jing-jing,JIANG Zhi-di,LIU Wei-yue
		DOI: 10.3969/j.issn.1000-1158.2022.03.16
		It's difficult to detect the starting point of signal during measuring time-of-flight of sound propagation, caused by which measurement error should be eliminate. A comprehensive measurement algorithm based on time-frequency analysis is proposed to obtain high-precision ultrasonic velocity. Firstly, cross-correlation method within time domain is used to measure the whole cycle time of sound wave traveled; then, phase difference in the signal frequency domain is used to obtain the ultrasonic propagation group delay information; finally, the high-precision time-of-flight measurement is obtained by combining time and frequency domain information, so as to improve the measurement accuracy of sound velocity. By building the sound velocity measurement platform employed “FPGA + microprocessor” architecture, results show that the algorithm is effective and instructive to practice.
		2022 Vol. 43 (3): 405-411 [Abstract] ( 182 ) HTML (1 KB) PDF (1968 KB) ( 569 )

	412	Exploring the CMP Process for Josephson Junction Arrays Used in Voltage Standard
		ZHAO Xin,CAO Wen-hui,LI Jin-jin
		DOI: 10.3969/j.issn.1000-1158.2022.03.17
		Chemical mechanical planarization (CMP) process on SiO2 layer is useful for the yield of highly integrated superconducting circuits especially for the ones with stacked Josephson Junction Arrays. Firstly, the CMP process is explored for the planarization on thermal oxide SiO2 and Chemical vapor deposition (CVD) deposited SiO2 layers. The test results show that the polishing rates for the two films above are 2nm/s and 3nm/s, respectively. And the differences in global material removal height within the wafer are both below 20nm. Then it is applied to the fabrication process of Josephson Junction Arrays. The Atomic force microscope (AFM) height profile scan on the junction unit indicates that the Step height (SH) is reduced from 240nm to 25nm and the surface roughness, which is acquired from a 2×2μm² area on the capping SiO2 isolating layer, is about 0.535nm, and therefore the CMP process on junction arrays patterned wafer provides sufficient process windows for subsequent fabrication processes.
		2022 Vol. 43 (3): 412-415 [Abstract] ( 288 ) HTML (1 KB) PDF (1287 KB) ( 413 )

	416	Carbon Dioxide Concentration Measurement of Fixed SourceBased on Herriott Absorption Cell
		MA Lu-yao,MA Ruo-meng,ZHU Xiao-yi,LUO Yong-jia,REN Ge,LIN Hong
		DOI: 10.3969/j.issn.1000-1158.2022.03.18
		Accurate carbon emission measurement is an important step to achieve the goal of "carbon peak and carbon neutral". Among all sources of emissions, the emission of carbon dioxide from point sources is a major factor in the greenhouse effect. Therefore, it is important to accurately measure the concentration of carbon dioxide from point sources. Based on the principle of near-infrared molecular absorption spectroscopy combined with multiple reflection direct absorption spectroscopy, an accurate method was established for the measurement of CO2 concentration using 35% CO2/N2mixture.CO2 transitions from (30012)←(00001)R16e of 6359.97cm-1 to (30012)←(00001)R18e of 6361.25cm-1, the spectral line intensity of R18e was calculated.By comparing the absorption areas of 35% CO2/N2mixtures with other CO2/N2 mixtures, concentrations of 15%, 10%, and 5% CO2/N2 mixtures can be obtained. The results show that the theoretical method and experimental results can well characterize the concentration of the gas to be measured, and the uncertainty of measurement is comparable to that of the weighing method based on balance.
		2022 Vol. 43 (3): 416-419 [Abstract] ( 281 ) HTML (1 KB) PDF (1053 KB) ( 445 )

	420	Uncertainty Assessment of Industry Plant Accounting Carbon Emissions
		JIANG Zhong,ZHANG Liang,WANG Hai-feng,ZHAO Jun-shuai,ZHAO Bu-hui,WANG Chi
		DOI: 10.3969/j.issn.1000-1158.2022.03.19
		Industry plants are the main traders in China's carbon trading market.Due to the large amount of default data used in carbon verification, the credibility of emissions data is reduced, and the uncertainty of emissions data has not been evaluated.After measuring the carbon emissions of 6 enterprises in 3 industries, the uncertainty of the carbon emissions data calculated by default value, measured value and their combination are analyzed and studied by using the Monte Carlo (MC) uncertainty evaluation method.The results show that, compared with the default values, only measuring low calorific value (using oxygen bomb calorimetry) can reduce the uncertainty by 9.0%.When the industrial analysis method is used to measure the low calorific value, the emission uncertainty can be reduced by 8.3%.Measuring low calorific value (using oxygen bomb calorimetry), and the carbon content can reduce the uncertainty by 16.6%.Measuring low calorific value (using oxygen bomb calorimetry), the carbon content and carbon oxidation rate can reduce the uncertainty by 16.9%.If all parameters are measured, the uncertainty can be reduced by 17.1%.
		2022 Vol. 43 (3): 420-426 [Abstract] ( 236 ) HTML (1 KB) PDF (913 KB) ( 504 )

	427	Development of Reference Material for White Blood Cell Count in Urine Sediment
		LIU Ying-ying,ZHANG Ling,YANG Qiao-si
		DOI: 10.3969/j.issn.1000-1158.2022.03.20
		After the cell morphology of the fixed human white blood cells was investigated by scanning electron microscopy, the reference material candidate of white blood cell count in urine sediment was prepared. High throughput microscopic imaging technology and flow cytometry were used to jointly determine the value of reference material candidates; the homogeneity and stability were investigated by variance analysis and regression curve; the interoperability of matrix effect was verified with 20 clinical samples, and the uncertainty of reference material was evaluated. The concentration of the standard substance for white blood cell count in urine sediment is (516.0±50.5 )cells/μL(k=2), which has good uniformity and stability. It can be stored for 12 months at 4 ℃, and has good interoperability with clinical samples. The reference material can be used for the periodic calibration and quality control of white blood cell count by the automatic urine sediment analyzer in clinical detection, as well as the confirmation and validation of analytical methods of relevant tests.
		2022 Vol. 43 (3): 427-432 [Abstract] ( 196 ) HTML (1 KB) PDF (1396 KB) ( 259 )

	433	Use of FTIR for Analyzing Hydrogen Fluoride Standard Gas at Low Concentrations
		LI Long,ZHANG Ti-qiang,YAO Qiang,HU Shu-guo,QIU Ni,DENG Bao-jia,ZHANG Ying,ZHANG Shi-ling,GAI Liang-jing
		DOI: 10.3969/j.issn.1000-1158.2022.03.21
		A method was proposed for analyzing hydrogen fluoride (HF) standard gas with low concentrations by using FTIR, of which the characteristic absorption region between 4100～4300cm-1 was used to identify and determine HF. A series of gas mixtures were prepared through the dilution of a mother cylinder standard, and produced 6 lower concentrations: 120, 100, 80.0, 60.0, 40.0, 20.0μmol/mol. Furtherly, the repeatability, linearity, and limit of detection (LOD) were evaluated. The results showed that the response value of the instrument is linear with the concentration of standard gas in the range of 20.0～120μmol/mol, and R2 is 0.9979; the repeatability of each concentration point is between 0.34%～1.1%; the detection limit is about 2.04μmol/mol.
		2022 Vol. 43 (3): 433-436 [Abstract] ( 200 ) HTML (1 KB) PDF (790 KB) ( 281 )

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