Journal of Shaanxi Normal University(Natural Science Edition)

  • Simulation method of polarization imaging in the scattering medium and its applications

    HU Haofeng;LI Tianci;SHEN Linghao;School of Future Technology, Tianjin University;School of Marine Science and Technology, Tianjin University;School of Precision Instrument and Opto-Electronics Engineering,Tianjin University;

    The visible optical polarization simulation data set in the scattering medium is relatively scarce, which limits the polarization imaging algorithm in the development and verification for the scattering medium. By considering the effects of scattering degeneration and light in the scattered environment on polarizing imaging, a polarizing image simulation method in the scattered medium is proposed. First, the physical render is used to simulate the propagation path of light and obtain the non-degraded polarization images through the polarized filter. After that, the real scattering environment data set(underwater and foggy environment) was used to determine the scattering degradation parameters in different environments. These parameters are then integrated with the scattering degradation model to generate simulated scattering polarization images. The simulation results closely match the image in real scattering environments. The DoLP(degree of linear polarization) images and AoP(angle of polarization) images reflect the phenomenon of depolarization in real scattering environments. Simulating polarization images can be used to analyze the polarization properties of the object and background in the scattered medium, and can provide a solid foundation for improving various polarized scattering algorithms.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 1141K]

  • Research progresses of code-multiplexing multispectral ghost imaging

    WANG Tiancheng;GUO Zhongyi;School of Computer and Information, Hefei University of Technology;

    Multispectral ghost imaging(MGI) based on code-multiplexing is a novel imaging technology that significantly enhances spectral imaging performance through cleverly designed encoding and decoding strategies, characterized by simplification and intelligence. This paper starts from the fundamental principles and key technologies of the MGI and thoroughly explores various coding multiplexing strategies and their reconstruction algorithms, primarily including coding multiplexing strategies based on random patterns, Hadamard patterns, and Fourier patterns, as well as corresponding reconstruction algorithms such as compressed sensing, Fourier inverse transform, and deep learning. These approaches exhibit unique characteristics in extracting the spatial structure and spectral properties of the target scene, showing different imaging advantages and applicable scenarios. However, the technique still faces challenges such as low projection efficiency and high computational complexity. In the future, it is expected to further improve the imaging performance of the MGI system through more efficient image reconstruction algorithms, intelligent technologies and advanced optics to meet the high-quality imaging needs of complex scenes.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 1213K]

  • Polarimetric dehazing method based on low-rank approximation and multiple virtual-exposure fusion

    ZHOU Yifu;WEI Hanyue;MA Feiya;YANG Rui;LIANG Jian;REN Liyong;School of Physics and Information Technology, Shaanxi Normal University;Xi'an Key Laboratory of Optical Information Manipulation and Augmentation (OMA);Robust (Xixian New Area) Opto-Electro Technologies Co., Ltd;

    The polarization parameter images in polarization dehazing algorithms are highly susceptible to noise interference, and the brightness of the dehazed images is unstable. This leads to the algorithm's inability to adapt universally to different lighting conditions. To address this issue, a new polarization dehazing algorithm is proposed, which introduces a novel polarization parameter image based on low-rank approximation to reduce noise interference. Additionally, a multi-exposure fusion method is employed to compress the image's dynamic range. Comparative experiments demonstrate that this method effectively removes haze from images, exhibiting strong robustness and significantly improving the overall quality of haze-affected images captured in various environments. In terms of standard deviation, image information entropy, NIQE and PIQE, the indicaters of the proposed method are improved by 22.99%,4.06%,17.42%,32.89% and 33.33%,2.80%,12.31%,76.14% respectively compared with the method proposed by Schechner and dark channel method.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 1278K]

  • Three dimensional tomographic microscopy based on large-field optical sectioning structured illumination

    WEN Tongqiang;CHEN Xiaofei;WEN Kai;GAO Peng;School of Mechanical and Electronic Engineering, Luoyang Institute of Science and Technology;School of Physics, Xi'dian University;Key Laboratory of Optoelectronic Perception of Complex Environment,Ministry of Education;Engineering Research Center of Information Nanomaterials,Universities of Shaanxi Province;

    This study introduces a technique known as large-field optical sectioning structured illumination microscopy(large-field optical sectioning structured illumination microscopy, LF-OS-SIM) designed for three-dimensional tomographic microscopic imaging of thick specimens. The technique utilizes a one-dimensional grating projection to generate a striped structured light field, in conjunction with a spatial light modulator(spatial light modulator, SLM) for fast phase-shifting of the structured light spectrum. Compared to conventional OS-SIM techniques that are based on SLM/DMD projection, LF-OS-SIM enhances the spatial bandwidth product(spatial bandwidth product, SBP) by 4.7 times. Additionally, digital phase-shifting using the SLM is implemented to achieve a slicing speed of 20 frames per second. The LF-OS-SIM was employed for three-dimensional tomographic microscopic imaging of objects such as coins, three-dimensionally distributed fluorescent beads, and biological specimens. The results indicated that the imaging field of view(FOV) for LS-OS-SIM reached 1 030×780 μm~3, with an axial tomographic imaging accuracy of 4.0±0.39 μm. Given its wide field of view, high resolution, and rapid slicing capabilities, LS-OS-SIM is anticipated to be extensively applied in the three dimensional imaging of both industrial microdevices and biological samples.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 1072K]

  • Applications of fully automatic Mueller matrix microscopic imaging technology in distinguishing tissue microarray

    WEI Hanyue;ZHOU Yifu;MA Feiya;YANG Rui;LIANG Jian;REN Liyong;School of Physics and Information Technology, Shaanxi Normal University;Xi'an Key Laboratory of Optical Information Manipulation and Augmentation (OMA);Robust (Xixian New Area) Opto-Electro Technologies Co., Ltd;

    In order to achieve non-destructive and rapid inspection of tissue microarrays, a fully automatic Mueller matrix microscopic imaging system was constructed by using the polarization imaging principle of the Mueller matrix. By integrating polarization optical components and imaging equipment with automatic control, this system can perform automatic imaging. The collected polarized image data is processed by using the Mueller matrix polar decomposition and Mueller matrix transformation algorithms to extract the key polarization characteristic parameters describing the sample. The results showed that in the experiment of distinguishing cervical cancer tissue samples from normal cervical tissue samples, the equivalent waveplate fast-axis azimuth θ and linear phase retardance δ are effective polarization parameters. By using statistical analysis, gray level co-occurrence matrix analysis and Tamura image processing methods to process the polarization parameter images, clear indications for diagnosing cervical cancer can be obtained. The fully automatic Mueller matrix microscopic imaging system can achieve rapid diagnosis of cancer by integrating multiple samples without frequently changing slices or switching to a high power objective.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 772K]

  • A method for high-resolution multispectral image reconstruction based on a superpixel segmentation operator

    YANG Rui;MA Feiya;WANG Fang;LIANG Jian;WEI Hanyue;REN Liyong;School of Physics and Information Technology, Shaanxi Normal University;Xi'an Key Laboratory of Optical Information Manipulation and Augmentation (OMA);Robust (Xixian New Area) Opto-Electro Technologies Co., Ltd;

    A high-resolution reconstruction method of split-focal plane mosaic images is proposed due to the low spatial resolution of split-focal plane multispectral cameras. The method realizes the acquisition of a demosaicking reflectance image, which shoot a diffuse reflective white plate to calibrate a division-of-focal-plane(DoF) mosaic sensor. The reflectance image and the DoF mosaic image are substituted into the fusion model of multispectral and hyperspectral images for high-resolution reconstruction. The reconstruction results of two reconstruction methods based on superpixel segmentation operators(least squares-multispectral data fusion method and regularized minimum rank-multispectral data fusion method) are analyzed, and the root mean square error of the two methods is about 0.12. The results show that the demosaicking method achieves better results in the migration of the high-resolution fusion model for spectral images, and the DoF mosaic images are highly restored in both the spatial and the spectral information.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 615K]

  • Design and output characteristics of cobalt ferrite magnetostrictive ultrasonic transducer

    JIANG Tao;XUE Changsheng;PI Jun;SHEN Zhihuang;HOU Dapan;HE Jinchun;College of Marine Equipment and Mechanical Engineering,Jimei University;

    Compared with the traditional nickel-based materials and rare earth-based materials, the magnetostrictive coefficient is small, the eddy current loss is large, and the preparation cost is high. Utilizing cobalt ferrite as the driving core of magnetostrictive ultrasonic transducer can achieve stable service and high-power output at elevated frequencies. In this paper, a longitudinal magnetostrictive ultrasonic transducer with resonant frequency of 30 kHz is designed based on the magnetostrictive characteristics of cobalt ferrite and the finite element simulation is used to analyze the dynamics and magnetic field of the transducer. The output characteristics of the cobalt ferrite magnetostrictive ultrasonic transducer are tested by impedance matching. The resonant frequency, output amplitude and working temperature of the prototype are tested. The results show that the magnetic field intensity is 0.1~0.25 T(301~653 Oe), which can meet the driving requirement of cobalt ferrite in the best driving range(250~750 Oe).When the driving voltage is 12 V and the signal gain is 20 dB, the actual resonant frequency of the transducer is 29.8 kHz, the output amplitude is 3.75 μm, and the stable working temperature is 60 ℃. The experimental results verify the reliability and application potential of cobalt ferrite in the field of magnetostrictive transducers.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 638K]

  • Application and performance optimization of ultrasonic vibration-assisted press-fitting technology in interference fits

    WANG Hao;WANG Haochen;DU Yunlong;CHENG Junqiang;YAN Lutao;School of Automation, Beijing University of Posts and Telecommunications;Shaanxi Fast Gear Company Limited;CRRC Nanjing Puzhen Company Limited;

    In the process of interference fit, in order to make the contact surface fit more closely and reduce the wear between the contact surfaces, an ultrasonic vibration-assisted press fit structure is designed. The dimensions of the horn are determined based on the matching of the output end of the horn with the press fit component, and the ultrasonic vibration frequency and power of the device are changed by altering the type and quantity of the vibrator. The results indicate that after the introduction of ultrasonic vibration, the press fit stress on the inner surface of the hub decreases by 20%, and the stress on the outer surface of the bearing decreases by 17%. With the increase of ultrasonic frequency and power, the press-fit force decreases by 10% to 20%. The greater the ultrasonic vibration power and the higher the frequency, the smaller the press fit force required for interference fit. The introduction of ultrasonic vibration in the press fit process effectively improves the connection performance of the interference fit and reduces the interface loss of the connection surface.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 709K]

  • Study on vibration modes of Janus-Helmholtz transducer and Janus-Hammer Bell transducer

    CHEN Baoku;GE Xiaohui;LI Junbao;Institute of Acoustics, Chinese Academy of Sciences;School of Physical Sciences, University of Chinese Academy of Sciences;Beijing Engineering Technology Research Center of Ocean Acoustic Equipment;

    Janus-Helmholtz(JH) transducers and Janus-Hammer Bell(JHB) transducers have similar appearance and structure, but their vibration modes are different. This article firstly analyzes the structural parameters corresponding to different vibration modes in JH transducer and JHB transducer. Under the conditions determined by other parameters, through theoretical calculation, it is concluded that the relationship between the axial length L of the ring shell in the JH transducer and the inner radius a of the ring shell should satisfy 2<L/a<5.7. The value range corresponding JHB transducer is 0.1<L/a<0.3. Then the finite element special boundary condition setting method is used to analyze the vibration modes corresponding to the resonance peaks of the JH transducer and the JHB transducer. It is concluded that the lower-frequency vibration mode in the JH transducer is the Janus longitudinal vibration, and the high-frequency vibration mode is the cavity resonance mode.The lower-frequency vibration mode in the JHB transducer is the Janus longitudinal resonance, and the higher-frequency vibration mode is the ring breathing mode. Finally, the radial and axial transmitting voltage responses of the JH transducer and the JHB transducer are compared to analyze work performance under different working modes, and it is concluded that the JH transducer can achieve a wider operating bandwidth and a higher transmitting voltage response. The working bandwidth of JHB transducer is narrow, but the transmitting voltage response in the radial direction has small fluctuations, and the transmitting voltage response in the axial direction has large fluctuations.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 540K]

  • Characterization method for ultrasonic vibration of micro tools in ultrasonic machining based on radiated acoustic pressure

    SUN Yijia;GONG Hu;ZHAO Chunyang;LIU Xuhui;ZHU Junchao;School of Electrical Engineering and Automation, Tianjin University of Technology, Tianjin Key Laboratory for Control Theory & Applications in Complicated Systems;School of Precision Instrument and Opto-electronics Engineering,State Key Laboratory of Precision Measuring Technology & Instruments,Tianjin University;Beijing Institute of Control Engineering;

    It is a typical application of ultrasonic machining to superimpose ultrasonic vibration on micro tools for precision machining of small structural parts. In ultrasonic-assisted machining, the ultrasonic vibration of the tool is an important parameter that affects the machining quality. However, due to their micro diameter, measuring directly or indirectly the ultrasonic vibration of micro-tools with complex geometry by using the exist method poses a current challenge. To solve the problem, an acoustic characterization method for the micro-tool's ultrasonic vibration is proposed. The relationship between the tool ultrasonic vibration and the radiated sound pressure is studied theoretically. Additionally, the differences between the measured sound pressure under different measuring conditions and the ideal sound pressure radiated by the tool are analyzed, and the sound pressure distribution radiated by different micro-tools is measured. Then a sound pressure measurement strategy is proposed and the corresponding experiment platform is established to characterize the ultrasonic vibration of the micro-tool. By using the acoustical measurement strategy, the working frequency of micro twist drill with different diameters(0.1~0.9 mm) is identified and the relative amplitude of tool vibration is quantified. The method based on radiative sound pressure can be used to in situ characterize the ultrasonic vibration state of micro-tools at low cost and high adaptability, which supplies a fundamental tool for the ultrasonic-assisted micro-machining process study.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 707K]

  • Study on ultrasonic intrinsic tag identification technique

    HE Shengping;ZHANG Yonglong;ZHANG Wei;LIU Yu;HE Xiping;Luzhou High Technology Institute;School of Physics and Information Technology, Shaanxi Normal University;

    To protect valuable items from tampering and replacement, a novel ultrasonic intrinsic tag technology for identifying important item feature information is proposed. The ultrasonic phased array system is established as the echo acquisition and processing platform. An identification algorithm is proposed, and the ratio of the power spectrum of sample signals of two items is calculated as the identification feature. An item identification system is designed based on the confidence determination threshold, and the corresponding identification program is compiled. A prototype is built and tested by use of various types of items such as ceramic items and the metals with the same and different materials. The results show that in 135 times of the identification experiments, 133 times are accurately identified with the accurate rate of identification of 98.52%, the misreport rate of 0.74%, and the underreporting rate of 0.74%. The average time of signal acquisition and identification for an item is respectively about 135 seconds. The proposed ultrasonic intrinsic tag identification technique satisfies the needs of specific occasions and has a broad application prospect.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 362K]

  • The application of rotary ultrasonic compound electrolytic grinding technology in difficult-to-machine material

    RONG Qin;CHEN Yuanyuan;HUANG Dazhong;ZHU Yongwei;College of Mechanical Engineering ,Yangzhou University;

    Rotational ultrasonic effects were integrated with grinding and electrolysis effectively to achieve precision and high-efficiency processing of difficult-to-machine materials and complex shaped parts. A rotary ultrasonic composite electrolytic grinding system was designed and developed. Experimental schemes were designed to conduct mechanical grinding, ultrasonic grinding and rotary ultrasonic combined electrolytic grinding experiments on aluminum and SiCp/Al particle-reinforced ceramic materials. The forming mechanism of rotary ultrasonic combined electrolytic grinding is analyzed, and the influence mechanism of different parameters on machining precision, efficiency and surface quality is studied. Based on its mechanism, the parameters of rotary ultrasonic combined electrochemical grinding system were optimized. The results show that rotary ultrasonic combined electrochemical grinding can effectively reduce the cutting force and heat, ensure the removal of electrode materials and electrolyte circulation renewal in time, and enhance and stabilize the machining effect.When the voltage is 3 V, the precision of machining an aero-engine blade can reach 0.01 mm and the surface roughness can be less than 0.80 μm.The method of rotary ultrasonic combined electrochemical grinding has obvious technical advantages.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 830K]

  • The impact of aerobic exercise on heart rate variability in adolescents with depression and its clinical significance

    YU Jianhua;YOU Li;WANG Qiang;ZHAO Peng;QIAN Haidong;Sports Department, Nanjing University of Aeronautics and Astronautics;Department of Rehabilitation Medicine, The Affiliated Brain Hospital of Nanjing Medical University;Department of Medical Psychology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School;Zhangjiagang Sports School;

    To clarify the dynamic changes and clinical significance of heart rate variability in adolescent depression with aerobic exercise therapy, 60 students of mild to moderate depression enrolled in 2022 were divided into the study group(5 cases dropped, 25 cases completed) and the control group(2 cases dropped, 28 cases completed) equally. The patients in the study group received aerobic exercise therapy for 12 weeks, the patients in the control group did not receive any treatment.The clinical efficacy and heart rate variability index between the two groups were compared.The clinical efficacy and cure rate of the study group were significantly higher than those of the control group at the end of the 12th week(P<0.05).The 17-item Hamilton Depression Scale(HAMD-17) score in the two groups was significantly lower than that at baseline(P<0.01).Compared with the control group, the study group showed a more significant decrease in HAMD-17 at the end of the 12th week(P<0.001). The standard deviation of NN intervals(SDNN),standard deviation average of NN intervals(SDANN), and root mean square of successive RR interval differences(RMSSD) in the study group at the end of the 12th week were significantly increased than those before treatment(P<0.001).Compared with the control group, the scores of SDNN, SDANN, and RMSSD in the study group at the end of the 12th week changed more significantly(P<0.001). Negative correlations were found between baseline HAMD-17 score and SDNN, SDANN, and RMSSD(r=-0.343, P=0.012; r=-0.328, P=0.017; r=-0.401, P=0.003; respectively). The results indicate that 12-week aerobic exercise can significantly improve depression symptoms and autonomic nervous system function in adolescent depression patients. The severity of depression is related to impaired autonomic nervous system function, and heart rate variability can become a biological indicator for evaluating the efficacy of aerobic exercise in treating depression.

    2024 06 v.52;No.216 [Abstract][OnlineView][Download 328K]
  • 2024 06 v.52;No.216 [Abstract][OnlineView][Download 124K]
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