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    Deadlock-Free Routing Algorithm of 2D-Torus Network-on-Chip Based on FPGA
    LI Zhen-ni, LI Jing-jiao, WANG Jiao, YANG Dan
    2021, 42 (1):  1-6.  DOI: 10.12068/j.issn.1005-3026.2021.01.001
    Abstract ( 975 )   HTML ( 42)   PDF (1619KB) ( 624 )  
    The topology and routing algorithm of network on chip (NoC) directly influence the transmission delay and the transmission efficiency of the network-on-chip. A new deadlock-free routing algorithm for NoC was proposed based on 2D-Torus topology. By changing the position of packets that are restricted to turn during NoC routing, the adaptive routing condition of network-on-chip was guaranteed, and the delay of network-on-chip was reduced. The 2D-Torus NoC based on this routing algorithm was designed and implemented on FPGA hardware platform, and then was tested. The experimental results indicated that the NoC based on this routing algorithm can meet the performance requirements of network-on-chip data communication for multi-direction and multi-channel.
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    Information & Control
    Retinal Blood Vessel Segmentation Method Based on Multi-scale Convolution Kernel U-Net Model
    YANG Dan, LIU Guo-ru, REN Meng-cheng, PEI Hong-yang
    2021, 42 (1):  7-14.  DOI: 10.12068/j.issn.1005-3026.2021.01.002
    Abstract ( 1100 )   HTML ( 28)   PDF (1864KB) ( 654 )  
    Aiming at the computer-aided diagnosis of diseased retinal vascular structure, a retinal blood vessel segmentation method of multi-scale convolution kernel U-Net model was proposed. Based on the U-Net model, a multi-scale convolutional neural network structure combining with the Inception module and the maximum index value upsampling method was designed. In the network training stage, operations such as rotation and mirroring were used to expand the data sets, and the CLAHE algorithm was used for image preprocessing. The dual-channel feature map obtained after training was normalized by Softmax. Finally, the normalized result was iteratively optimized by the improved cost loss function, then a complete retinal vessel segmentation model was obtained. Experimental results showed that the proposed method on the DRIVE data set achieved an accuracy of 0.9694, a sensitivity of 0.7762, and a specificity of 0.9835. The proposed method has better segmentation effect and generalization ability than the U-Net model, and shows its competitive results compared with other existing methods.
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    Dynamic Modeling and Simulation of Micro-particles Experienced Dielectrophoretic Effect
    HU Sheng, WANG Ke, CAI Lu
    2021, 42 (1):  15-20.  DOI: 10.12068/j.issn.1005-3026.2021.01.003
    Abstract ( 1022 )   HTML ( 34)   PDF (1080KB) ( 516 )  
    There exists tough convergence, burden computation, and low efficiency for solution to partial difference equations using Velocity-Verlet or ODE algorithms analyzing characteristics of particle motion. The finite element software COMSOL Multiphysics 5.3a, which could be used to solve Laplace equation quickly in AC/DC module when these reasonable boundaries were chosen, provides the precondition for calculating dielectrophoretic force. In terms of particle tracing module in COMSOL software, the particles experienced dielectrophoretic effect were simulated through the selection of both time step and range when dielectrophoretic, Stokes drag, repulsive, and buoyant forces were taken into the table of stress parameter in particle tracking module. The results illustrated that this approach is capable of simulating the motion of such particles exerted by dielectrophoresis effect, reducing the complexity of program and improving man-machine visualization of dynamic simulation, and are consistent with Velocity-Verlet or ODE algorithms.
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    Sentiment Community Detection Algorithm for Sina Weibo
    HAN Dong-hong, ZHANG Hong-liang, ZHU Shuai-wei, QI Xiao-long
    2021, 42 (1):  21-31.  DOI: 10.12068/j.issn.1005-3026.2021.01.004
    Abstract ( 1001 )   HTML ( 23)   PDF (854KB) ( 465 )  
    Sentiment community detection in social networks would be very valuable in many areas, such as public health, public opinion monitoring and so on. A framework of sentiment community detection was established on Sina Weibo. Firstly, the sentiment expression features and lexicon of Weibo were combined, and the classification model SL-SE-NB (naive Bayes algorithm based semi-lexicon and semi-emoji) was proposed to predict the sentiment polarity of texts. And then, the UTK (user-topic-keywords) model based on LDA (latent Dirichlet allocation) was proposed to extract user topics. Based on LPA(label propagation algorithm) and adding topic concepts, SMB-LPA (label propagation algorithm based seeds and min-edge betweenness) was proposed to discovery sentiment community. Finally, the experimental results proved the effectiveness and efficiency of the proposed algorithms.
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    AVS-S Coding Based on Background Model
    SANG Ai-jun, YU Huan, ZHANG Han-yu
    2021, 42 (1):  31-36.  DOI: 10.12068/j.issn.1005-3026.2021.01.005
    Abstract ( 583 )   HTML ( 6)   PDF (1551KB) ( 185 )  
    In order to improve the coding efficiency of surveillance video, a new background frame update method was proposed, namely, iterative update mean value method, under the coding framework of AVS surveillance extension grade. The nature of the pixel in a certain frame was determined according to the principle of different frequencies of occurrence of a certain pixel in the foreground area and in the background area. Through the test comparison of the surveillance video Crossroad, Overbridge and Classover, the pixel values of the background model corresponding to the pixels of different nature were obtained. The results showed that the shortcomings that slow moving objects are difficult to eliminate from the background are improved to a certain extent in this experiment. At the same time, the integrity of the background information is strengthened and the quality of the background frame is improved. Under the conditions of the same bit rate and the same peak signal-to-noise ratio, compared with the AVS benchmark method, the average code saving rate is 43.283% and the peak signal-to-noise ratio is increased by 1.186dB on average. The coding efficiency of its surveillance video is also improved.
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    Materials & Metallurgy
    Austenite Evolution in Low-Carbon Steel Under Endless Strip Production Process
    ZHOU Xiao-guang, WANG Duo, ZHANG Dong-hang, LIU Zhen-yu
    2021, 42 (1):  37-43.  DOI: 10.12068/j.issn.1005-3026.2021.01.006
    Abstract ( 659 )   HTML ( 14)   PDF (1780KB) ( 286 )  
    The effects of the direct rolling of cast billet, large pass deformation and intermediate billet heating on microstructure evolution of austenite in low-carbon steel were studied in direct rolling experiment of wedge-shaped cast billet and hot rolling experiment of large pass deformation with intermediate billet heating, and were also compared with austenite evolution in the conventional hot rolling process. The results show that grain size of the austenite decreases gradually with increasing the reduction rate. Compared with the reheating rolling process, the austenite grains after the direct rolling process are coarser in the reduction rate of 48%, 53.6% and 66.7%, while the deformed microstructure becomes finer and more homogeneous when the reduction rate is 72.3%. In comparison with the conventional hot rolling process, the large pass deformation promotes austenite recrystallization in the rough rolling stage, while the intermediate billet heating process improves the uniformity of grain size in the austenite.
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    Effects of ZrO2 Addition Amount on Microstructure and Mechanical Property of WC-6Co Prepared by Spark Plasma Sintering
    BAO Jun-feng, YU Yue-guang, JIA Cheng-chang
    2021, 42 (1):  43-48.  DOI: 10.12068/j.issn.1005-3026.2021.01.007
    Abstract ( 554 )   HTML ( 7)   PDF (4214KB) ( 110 )  
    A series of WC-6Co cemented carbides with different amount of ZrO2 addition were quickly prepared by spark plasma sintering (SPS) and the effects of ZrO2 addition on the microstructure and mechanical properties of the alloys were investigated. The results show that with the increasing ZrO2 additive amount, the microstructure of the sample becomes more condensed, the relative density is greater and the hardness and fracture toughness also increase. When the mass fraction of ZrO2 addition is 3%, the performance of the tested sample is the best one, in which the relative density is 96.7%, the Vickers hardness is 20.28kN·mm-2 and the fracture toughness is 12.7MPa·mm1/2. It is found that the ZrO2 can enhance the sintering by promoting the ion diffusion and the particle rearrangement, leading to the improvement of the relative density and mechanical property of the cemented carbides.
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    Experimental Study on Particle Mixing Process in Rotating Drum
    RONG Wen-jie, QIN De-yue, LI Bao-kuan, FENG Yu-qing
    2021, 42 (1):  49-54.  DOI: 10.12068/j.issn.1005-3026.2021.01.008
    Abstract ( 706 )   HTML ( 10)   PDF (3383KB) ( 324 )  
    The mixing and separating process of different-sized particles in a self-designed rotating drum were explored, where the glass beads were taken as particles. The power consumption of rotating drum under different operating parameters were measured. The results show that the particle separation is more evident when the drum is operated at high fill level, where the small particles surrounded by large particles are mostly observed. When the filling rate is low, it is unobvious for the particle separation of the similar size particles at different rotating speeds. The larger difference of the particle size, the more particle separation occurs. With the increasing rotational speed and fill level, the power consumption increases, while the power consumption is relatively less sensitive to the particle size ratio.
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    Dissolution and Agglomeration Behavior of Alumina in Aluminum Electrolysis
    YANG You-jian, LI You-cai, WANG Zhao-wen, SHI Zhong-ning
    2021, 42 (1):  55-61.  DOI: 10.12068/j.issn.1005-3026.2021.01.009
    Abstract ( 1249 )   HTML ( 13)   PDF (1705KB) ( 569 )  
    The agglomerating behavior and heat transfer process upon the addition of smelting grade alumina into cryolite electrolyte were studied using the see-through cell platform, especially the formation and dissolution of the agglomerate. The dissolution rate of the alumina agglomerate was measured, and physicochemical properties of the alumina agglomerate was analyzed. The influence factors, such as the electrolyte temperature, alumina feeding amount, alumina preheating temperature and superheat during the dissolution and formation of the agglomerate were investigated through heat balance calculation. The results show that during the re-establishment of a new heat balance after alumina feeding, the absorbed heat for alumina dissolution is firstly supplied by electrolyte cooling. When the temperature drop is above the liquidus temperature of the electrolyte, which cannot provide enough heat for the dissolution, electrolyte condensation would take place and release more heat. In contrast to a relatively high electrolyte temperature and high superheat, a high frequent and small amount of alumina feeding would benefit the electrolysis process.
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    Cathode Permeation Mechanism of Lithium in Aluminum Electrolysis
    WANG Yao-wu, YOU Jing, PENG Jian-ping, DI Yue-zhong
    2021, 42 (1):  62-67.  DOI: 10.12068/j.issn.1005-3026.2021.01.010
    Abstract ( 1116 )   HTML ( 8)   PDF (1459KB) ( 334 )  
    In the process of aluminum electrolysis, the proportion of lithium fluoride in electrolyte increases gradually due to the existence of a small amount of lithium oxide in alumina, and the lithium element permeates the cathode lining. The existent forms of lithium element in electrolyte and cathode carbon blocks were analyzed by X-ray diffraction and scanning electron microscope, and the cathode permeation mechanism of lithium element in aluminum electrolysis was studied. The results show that the lithium element in electrolyte is primarily in the form of LiNa2AlF6. Some lithium ions in molten electrolyte are reduced to lithium metal by aluminum and the Mole fraction of lithium in aluminum liquid is positively related to the Mole fraction of lithium fluoride in electrolyte. The lithium in the electrolyte permeating the cathode carbon blocks through the pores and cracks in the cathode carbon blocks is mainly in the form of fluorides. The lithium in the aluminum liquid cannot diffuse into the cathode carbon blocks.
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    Mechanical Engineering
    Machine Vision Automatic Inspection Technology of Optical Fiber Winding Based on Deep Learning
    LIU Yu, WEI Xi-lai, WANG Shuai, DAI Li
    2021, 42 (1):  68-74.  DOI: 10.12068/j.issn.1005-3026.2021.01.011
    Abstract ( 710 )   HTML ( 23)   PDF (1687KB) ( 794 )  
    Existing optical fiber winding inspection methods have poor generalization ability and environmental adaptability, and cannot be applied to industrial production. A machine vision method based on deep learning was proposed to classify the winding images during the winding process to solve the optical fiber winding problem. By considering the effect of the force between the optical fibers when the optical fiber was winding, the optical fiber winding model was established, and the speed expression of the arranging mechanism was proposed when the optical fiber was winding. The camera was used to collect a large number of optical fiber winding pictures to form a data set, and a neural network model was built and trained to classify the winding situation. Experimental verification showed that the accuracy of this method for gap state recognition is over 94.67%, and the accuracy of overlapped line recognition is 100%. The inspection speed is higher than the actual production winding speed. It is a favorable method that can be combined with the control system to replace manual winding and realize automatic precision winding.
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    Fluid-Solid-Thermal Coupling Characteristics of Ejector Valve Adjusting Structure
    LUO Zhong, SUN Yong-hang, GE Chang-chuang, XU Chun-yang
    2021, 42 (1):  75-82.  DOI: 10.12068/j.issn.1005-3026.2021.01.012
    Abstract ( 562 )   HTML ( 4)   PDF (3057KB) ( 245 )  
    Aiming at the structural strength of the valve adjusting structure of the marine gas turbine ejector under fluid-solid-thermal coupling, the three-dimensional flow field of the ejector and the structural model of the valve plate were established. The steady-state and transient simulation analysis of the flow field were carried out by using the computational fluid dynamics (CFD) method. Taking the transient simulation results as the boundary conditions of the finite element model, the sequential unidirectional fluid-solid-thermal coupling analysis including thermal, aerodynamic and centrifugal loads was carried out. The result showed that compared with the steady-state simulation, the trend of transient simulation results is similar, but the pressure difference is larger. The steady-state solution of the time-varying load may lead to underestimation of strength. For the valve adjusting structure, the thermal load plays a major role in the deformation and stress of the valve plate. The bending stress caused by the aerodynamic load can offset part of the bending stress caused by the thermal load, while the centrifugal load has little effect on the structure, which can be ignored. The analysis method can be used for the structural design and optimization of such typical motion adjusting structures as ejector valve adjusting structure.
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    Improved Model Based on A-V Model and Prediction of Uniaxial Ratcheting Effects
    CHEN Xiao-hui, ZHOU Yang, LIU Ming-yue, LIN Yong-cheng
    2021, 42 (1):  83-90.  DOI: 10.12068/j.issn.1005-3026.2021.01.013
    Abstract ( 593 )   HTML ( 4)   PDF (1777KB) ( 298 )  
    In view of the shortcomings of the A-V model which cannot well predict the initial stage of ratcheting effect of materials, the parameter γ2 in the A-V model was modified and Ramberg-Osgood (R-O) model and isotropic hardening were introduced to calculate the stress-strain curve. The material parameters of the A-V model were determined, and an improved A-V model was established to describe the cyclic plastic behavior of materials. The uniaxial ratcheting effects of Z2CND18.12N austenitic stainless steel and SS316L steel were predicted by using the improved A-V model, and the influences of average stress, stress amplitude, stress ratio and loading history on the uniaxial ratcheting effect were studied. The results showed that the ratcheting strain predicted by the improved A-V model is consistent with the experimental value.
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    Failure Simulation Analysis of Carbon Fiber Reinforced Polymer Laminate with a Hole in Axial Tension Process
    ZHANG Hua-wei, WU Jia-lu
    2021, 42 (1):  91-95.  DOI: 10.12068/j.issn.1005-3026.2021.01.014
    Abstract ( 651 )   HTML ( 9)   PDF (1027KB) ( 370 )  
    The progressive failure model of the composite laminate with a hole in the axial tension process was set up based on ABAQUS. The matrix tension failure, the matrix compression failure, the fiber tension failure and the fiber compression failure were considered by selecting two-dimensional Hashin as the damage criterion. The load condition and the failure mode were discussed, and the effects of the ply angle and the size of the center hole on the ultimate load were analyzed. The results showed that the dominant failure modes are matrix tension failure and the fiber tension failure, and the fibers are the strength source of the composite laminate. When the load direction does not agree with the fiber direction, the mechanical performance of the composite laminate degenerates. The mechanical performance of the composite laminate becomes worse as the center hole becomes larger, and is linear with the size of the center hole.
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    Compression Algorithm of Dual X-ray Security Inspection Images with High Dynamic Range
    YUAN Pei-xin, CHEN Ding-fu
    2021, 42 (1):  96-101.  DOI: 10.12068/j.issn.1005-3026.2021.01.015
    Abstract ( 768 )   HTML ( 14)   PDF (941KB) ( 411 )  
    In order to display dual X-ray images with high dynamic range from a security inspection system without losing details, a self-adaptive tone mapping algorithm based on the multiscale local edge-preserving filter was proposed. The input image was decomposed into one base layer and three detail layers by using the LEP filter. An adaptive logarithmic transformation was carried out in the base layer to compress the dynamic range and the three detail layers were enhanced by an adaptive Sigmoid function. Every detail layer image was fused with the base layer image and histogram equalization was taken considering noise and increasing contrast. The proposed algorithm was used to dispose the high and low energy X-ray images at the same time and both of them were combined according to their own merits, which could get a low dynamic range dual X-ray image with rich details. Experimental results showed that the proposed algorithm highly improves images information entropy, contrast improvement index and peak signal to noise ratio, which indicates that the image quality is successfully optimized.
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    Sensorless Control Algorithm for Permanent Magnet Synchronous Motors Considering Iron Loss
    ZENG Xiao-hua, CHEN Hong-xu, CUI Chen, SONG Da-feng
    2021, 42 (1):  102-110.  DOI: 10.12068/j.issn.1005-3026.2021.01.016
    Abstract ( 662 )   HTML ( 10)   PDF (1813KB) ( 469 )  
    Aiming at developing an effective and reliable sensorless control algorithm for permanent magnet synchronous motors, for the equivalent circuit model considering iron loss resistance, the differential expression of the torque current state was derived under the d-q rotating axis system and the α-β stationary axis system. On this basis, a sliding mode observer was designed to estimate the speed and rotor position signals. In order to verify the observation effect, the sensorless algorithm was simulated and compared under the two axis systems. A fusion observation algorithm based on the extended Kalman filtering was proposed according to the characteristics of the low accuracy of the rotor position signal under the d-q axis system and the high frequency chattering of the signals under the α-β axis system. Simulation results showed that the fusion observation algorithm has less error and good dynamic characteristics. Besides, the effectiveness of the fusion observation algorithm was verified by experiments.
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    Resources & Civil Engineering
    Depression of Starch on Fine Hematite Enhanced with Magnetic Seeding Aggregation
    WANG Dong-hui, YIN Wan-zhong, YANG Bin, QIN Hong-bin
    2021, 42 (1):  111-116.  DOI: 10.12068/j.issn.1005-3026.2021.01.017
    Abstract ( 593 )   HTML ( 10)   PDF (843KB) ( 180 )  
    The depression effect of starch on fine hematite is poor during the reverse flotation of hematite. Flotation tests, EDLVO calculations, particle size analysis and SEM analysis were used to investigate the depression effect of starch on fine hematite with the assistance of magnetic seeding aggregation. The results showed that the depression effect of starch on hematite decreased with the decrease of hematite particle size. The addition of magnetite enhanced the depression effect, which became more obvious with the increase of magnetite particle size. The attraction between magnetite of different sizes and fine hematite leads to the aggregation of magnetite with hematite particles, and the larger the particle size of magnetite, the stronger the attraction is. The magnetic seeding aggregation increased the apparent particle size of fine hematite, thus strengthened the depression effect of starch on hematite.
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    Rock Mass Structural Plane Classification Method Based on Improved Ideal Point Model
    WANG Shu-hong, ZHU Bao-qiang, ZHANG Ze
    2021, 42 (1):  117-123.  DOI: 10.12068/j.issn.1005-3026.2021.01.018
    Abstract ( 677 )   HTML ( 9)   PDF (568KB) ( 316 )  
    In view of the fact that the previous structural plane classification methods are mostly macro-qualitative analysis, which is not conducive to guiding actual engineering design and construction. A quantitative structural plane classification method based on the improved ideal point model was proposed. Firstly, considering various factors of structural plane classification, seven indicators were used for quantitative characterization, and a multi-index structural plane quantitative classification system was established. Then, based on the principle of minimum entropy, the weights obtained by analytic hierarchy process and entropy weight method were optimized, and the ideal point model was improved to obtain the optimal combination weight. Finally, the improved model was applied to the structural plane classification of Xinglong tunnel in Chongqing and compared with the actual engineering. The results show that the classification results obtained by improved ideal point model are consistent with the actual project, with an accuracy of 93.3%, which has strong reliability and engineering practicability. It can provide a new idea and method for rock mass structural plane classification.
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    Interaction Mechanism Between Granular Backfill and Rock Pillar Under Lateral Confined Conditions
    LE Zhi-hua, YU Qing-lei, ZHENG Hao-tian, CAO Yong-sheng
    2021, 42 (1):  124-130.  DOI: 10.12068/j.issn.1005-3026.2021.01.019
    Abstract ( 586 )   HTML ( 7)   PDF (1702KB) ( 301 )  
    In the dry filling mining method, in order to study the interactions between the granular backfills and surrounding rock, and analyze the influence of backfills on the mechanical properties of pillars, a self-made device was used to test the axial compressive properties of rock pillar confined by granular backfills and a series of compressive tests of rock pillar were conducted considering the various particle size of the granular backfills. The results show that the granular backfills improve the stress state of the rock pillar, and the peak and residual compressive strengths of rock pillar are enhanced due to the passive lateral support of the granular backfills. Meanwhile, the failure pattern of the rock pillar has changed. With an increase of the particle size of granular backfills, the interaction between the granular backfills and the rock pillar intensifies first and then weakens. On this basis of testing results, the model for bearing capacity of pillar is established considering the interaction between granular backfills and rock pillar, and the relationship between the deformation modulus of granular backfills and rock pillar is given.
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    Strain Measurement Method of Fully-Grouted Rock Bolt in Rock Mass Fractured Zone
    HAN Tao, JIN Chang-yu, LU Yu, LIU Dong
    2021, 42 (1):  131-138.  DOI: 10.12068/j.issn.1005-3026.2021.01.020
    Abstract ( 584 )   HTML ( 6)   PDF (4267KB) ( 216 )  
    Due to the effects of discontinuous deformation in fractured rock masses and complex shearing between the rock bolt and the grout, the strain of rock bolt in fractured zone can hardly be measured accurately. A fully-grouted rock bolt was prepared by using 3D printing, and strain gauges were installed inside and outside the bolt respectively. The evolution law of tensile strain in the fully-grouted rock bolt during the fracture propagation process was obtained by uniaxial compression test. It was found that the outer strain gauges were greatly affected by the shear deformation of the grout, and the measurement results are easy to be distorted when the plastic deformation capacity of the grout is high. However, the internal strain gauges could accurately obtain the complete strain of bolt. Finally, the failure process of rock bolt in fractured zone was numerically simulated by FLAC software, the influence of strain gauge location on the measurement results was verified, which further proved the reliability of measurement by strain gauges inside the rock bolt.
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    Dust Concentration Detection Technology Based on Fusion of Light Scattering Method and Charge Induction Method
    ZHAO Zheng, LI De-wen, WU Fu-xiang, LIU Guo-qing
    2021, 42 (1):  139-147.  DOI: 10.12068/j.issn.1005-3026.2021.01.021
    Abstract ( 710 )   HTML ( 13)   PDF (672KB) ( 516 )  
    In order to reduce on-line detection error of dust concentration, the basic principles of light scattering method and charge induction method were analyzed, and the limitations of the two methods were revealed. The structure and data of the light scattering subunit and charge induction subunit were fused, and a parallel automatic switching fusion subunit was developed. A dust concentration fusion detection algorithm was proposed. The experimental results showed that the detection error of the fusion subunit was ≤11.3%, 3.6% smaller than that of the light scattering subunit, and 3.5% smaller than that of the charge induction subunit. The average calibration resolution of the fusion subunit was 112.8, 1.27 times that of the light scattering subunit and 4.68 times that of the charge induction subunit. The calibration linearity of fusion subunit was the best. It was proved that the fusion technique overcame the limitation of light scattering method and charge induction method, further reduced the detection error and improved the calibration resolution and linearity.
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    Biologic Engineering
    A Method to Correct Stimulated Echo Artifact for Fast Spin Echo
    WANG Yan-fei, TAN Wen-jun, YANG Jin-zhu, KANG Yan
    2021, 42 (1):  147-152.  DOI: 10.12068/j.issn.1005-3026.2021.01.022
    Abstract ( 661 )   HTML ( 4)   PDF (674KB) ( 347 )  
    The principle of fast spin echo (FSE) producing stimulated echo and the relationship between stimulated echo and the phase angle of radio frequency pulse were investigated. For fast spin echo pulse sequence, a stimulated echo artifact correction method was proposed. The spin echo and stimulated echo were separated by two times of excitations, then the area of dispersion gradient was adjusted to make the center of stimulated echo coincide with that of the spin echo, and the phase angle of 180° refocusing pulse was modified to make the phase of stimulated echo and spin echo consistent. The correction method was tested and validated on a 1.5T superconducting MRI scanner. After stimulated echo artifact was corrected, the signal to noise ratio of the FSE image was improved by 57.08%, while the image artifact was reduced by 76.12%. The experimental results showed that the proposed method can effectively suppress stimulated echo artifacts on FSE image and improve the image quality.
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