水下无人系统学报

Target Tracking Algorithm for Underwater Acoustic Sensor Networks under DoS Attack

YAN Jing, YANG Jin, YANG Xian, LUO Xiaoyuan

2024, 32(6): 971-979. doi: 10.11993/j.issn.2096-3920.2024-0006

[Abstract](89) [FullText HTML] (28) [PDF 1933KB](30)

Abstract:
By considering the effect of underwater denial of service(DoS) attack and sound line stratification, the problem of target tracking based on an underwater acoustic sensor network(UASN) was studied in this paper. Firstly, a UASN architecture consisting of underwater sensors, surface buoys, and underwater targets was developed. Then, the underwater target movement model and the underwater DoS attack model were constructed, and an improved consensus-based unscented Kalman filter(UKF) underwater target tracking algorithm was proposed. Finally, the Cramer-Rao lower bound of the algorithm was derived, and the effectiveness of the algorithm was proved. Simulation and experiments show that the proposed algorithm can track the target effectively in an underwater environment, and the consensus-based UKF algorithm improves tracking accuracy.

Design and Simulation Analysis of Sound Absorption Structure for Acoustic Detection-Based Underwater Gliders

ZENG Donghai, WU Xinyu, YUAN Chang, PENG Yuxuan, ZHANG Jianxing, LI Baoren

2024, 32(6): 980-988. doi: 10.11993/j.issn.2096-3920.2024-0092

[Abstract](51) [FullText HTML] (17) [PDF 1853KB](13)

Abstract:
The radiation noise of mechanical noise has a significant impact on the acoustic detection performance of acoustic detection-based underwater gliders. In order to address this problem, this paper introduced sound absorption structure into the study of radiation noise of underwater gliders. Firstly, the theoretical models of different sound absorption structures were established, and according to the sound absorption theories of microperforated panel and porous materials, the composite sound absorption structure for reducing the radiation noise of underwater gliders was proposed, and the simulation analysis of the composite sound absorption structure was carried out by using Comsol software for guiding the design of the composite sound absorption structure. The simulation results show that the composite sound absorption structure of porous material layer-air cavity-microperforated panel-parallel air cavity has the best performance in the range of 0–2 000 Hz, and its average sound absorption coefficient is 0.663 in the range of 200–1 200 Hz, which can reduce the radiation noise of the underwater gliders under specific working conditions, weaken the interference of self-noise, and improve the detection ability of acoustic detection-based gliders.

Hybrid Energy Storage Control Method for Wave Energy Power Supply System in Comprehensive Observation Buoys

LIU Xu, CHEN Zhen, LIU Zhen, LI Ming

2024, 32(6): 989-999. doi: 10.11993/j.issn.2096-3920.2024-0070

[Abstract](45) [FullText HTML] (22) [PDF 2309KB](16)

Abstract:
Wave energy is a widely distributed green renewable energy source capable of providing continuous electrical power to comprehensive observation buoys. However, its rapid fluctuations and high peak-to-average ratio require hybrid energy storage systems to smooth out its energy fluctuations for a reliable electrical load supply. These hybrid energy storage systems need to balance power and energy density characteristics, and energy management strategies are important for fully utilizing the characteristics of different devices and extending the system’s lifespan. This paper focused on energy distribution and power control methods of energy storage systems in wave energy supply and proposed a power distribution and control strategy for hybrid energy storage system based on deep deterministic policy gradient(DDPG), so as to maintain bus stability and leverage the advantages of two energy storage technologies of batteries and supercapacitors. Simulation and physical experiments demonstrate that this strategy greatly reduces peak battery charge/discharge power, keeps bus voltage ripple below 1.6%, and significantly enhances the stability of the wave energy power supply system.

Parameter Tuning Method of Active Disturbance Rejection Controller for AUVs Based on VRFT

HOU Xiaodong, YANG Rui, LI Ming

2024, 32(6): 1000-1008. doi: 10.11993/j.issn.2096-3920.2024-0071

[Abstract](111) [FullText HTML] (48) [PDF 1401KB](24)

Abstract:
Active disturbance rejection control(ADRC) is model-independent and exhibits strong robustness against disturbances, effectively addressing the uncertainties of autonomous undersea vehicle(AUV) models and complex external environments. However, parameter tuning for active disturbance rejection controllers presents certain difficulties. To tackle this issue, a parameter tuning method based on virtual reference feedback tuning(VRFT) was proposed. Initially, an active disturbance rejection controller was designed for the yaw model of the AUV. Subsequently, a parameter tuning method for VRFT-active disturbance rejection was presented. Finally, to address the issue of angular sensor delay, a design method for an active disturbance rejection controller based on the Smith predictor was proposed. The simulation results demonstrate that this method can tune the parameters of the active disturbance rejection controller for AUVs solely based on the open-loop experimental input and output data under the condition of unknown model information, achieving the desired control effect.

Error Compensation for Dead Reckoning Based on SVM

LI Xin, WANG Xiaoming, WU Jianguo, ZHAO Jiwei, XIN Jiacheng, CHEN Kai, ZHANG Bin

2024, 32(6): 1009-1017. doi: 10.11993/j.issn.2096-3920.2024-0004

[Abstract](81) [FullText HTML] (39) [PDF 18526KB](16)

Abstract:
In the use of machine learning methods for error compensation in dead reckoning of an autonomous undersea vehicle(AUV), the neural network algorithm is commonly used. However, neural networks require a large number of training samples to achieve stable training results. To solve this problem, research was conducted on the application of support vector machine(SVM) for error compensation in dead reckoning. By utilizing SVM, an error compensation model was trained to correct the errors in dead reckoning, thereby improving navigational accuracy. The error compensation model takes seven parameters as input: pitch angle, roll angle, course angle, forward, right, and upward velocity of the Doppler velocity log(DVL) relative to the ground, and dead reckoning time of the AUV. The difference in latitude and longitude provided by the global positioning system(GPS) and inertial navigation system(INS) + DVL combination compared with latitude and longitude obtained from dead reckoning serves as the output of the model. The SVM trained model and the neural network trained model show a relative error of 0.28% and 0.93%, respectively, when the amount of data is limited. Through lake tests, it is concluded that the model trained by SVM can control the relative error of dead reckoning within 0.5%.

Omnidirectional Motion Trajectory Tracking Control Method for AUVs

XU Jiangpeng, WANG Junlei, TANG Yi

2024, 32(6): 1018-1028. doi: 10.11993/j.issn.2096-3920.2024-0084

[Abstract](174) [FullText HTML] (48) [PDF 2703KB](46)

Abstract:
The precise trajectory tracking capability of autonomous undersea vehicles(AUVs) is crucial for completing underwater tasks such as exploration, obstacle avoidance, and pipeline inspection. However, AUVs are typically underactuated systems that satisfy non-holonomic dynamic constraints, and they cannot track some specific trajectories or perform some specific underwater maneuvers, such as station-keeping U-turns and point-circling observations. Most researchers focus on improving the trajectory tracking capability of AUVs based on underactuated system theory. This paper, however, proposed a new omnidirectional motion trajectory tracking control method for AUVs from the perspective of structural improvement, drawing on the configuration design of remotely operated vehicles(ROVs). The method retained the original low-drag streamlined torpedo-like structural design and motion mode of AUVs while endowing them with a new omnidirectional motion mode. Using the Bluefin series AUV as an example, the paper designed and modified the omnidirectional motion structure and developed a trajectory generation algorithm based on the Hermite algorithm, a trajectory guidance algorithm based on the scaling factor, and a sailing-heading hybrid control algorithm. Both simulation and underwater experiments validate the control method. The results show this method can achieve omnidirectional navigation, solve motion constraint problems in AUV trajectory tracking, enable them to track any trajectory, and complete specific underwater maneuvers.

Multi-parameter Identification of Underwater Equipment Joint Motor

SHI Lin, HU Qiao, SHI Xindong, SUN Liangjie, ZHANG jian, LIU Haiyang

2024, 32(6): 1029-1038. doi: 10.11993/j.issn.2096-3920.2024-0062

[Abstract](59) [FullText HTML] (20) [PDF 1352KB](24)

Abstract:
With the rapid development of unmanned undersea systems, joint motors play an important role as the core driving devices of underwater robots, underwater manipulators, and other underwater equipment. In this paper, the on-line multi-parameter identification of an underwater joint motor is studied to solve the problem that the precision and stability of motor control are deteriorated due to the change of motor parameters under the influence of different working environments. Specifically, the method of increasing steady-state operating points is used to realize multi-parameter full rank identification. At the same time, to improve the accuracy and robustness of the identification method, this study investigates the feasibility of extended Kalman filter(EKF) and H_∞ filter(H-infinity filter, HIF) in the identification of motor parameters. Then a new joint estimation method based on adaptive EKF(AEKF) and adaptive HIF(AHIF) is proposed. Through simulation comparison, it is found that in parameter identification, the steady-state standard deviation of the proposed AEKF+AHIF joint estimation method is reduced by 84.7% compared with that of the AEKF method, and the accuracy is increased by 91.7% compared with that of the AHIF method. The joint estimation method can provide theoretical and technical support for the stable and efficient operation of underwater joint motors.

Combined Homing Guidance Law of Torpedo Based on Fuzzy Control

MU Baoming, CHENG Jianqing, PAN Feng

2024, 32(6): 1039-1044. doi: 10.11993/j.issn.2096-3920.2024-0073

[Abstract](65) [FullText HTML] (31) [PDF 930KB](13)

Abstract:
In the process of torpedo homing guidance, it is difficult for a single guidance method to adapt to different guidance phases and ensure the torpedo guidance effect effectively. For this reason, this paper designs a fuzzy combined guidance law based on the principle of fuzzy control by combining three different typical guidance methods, namely, fixed lead angle guidance method, proportional guidance method, and variable structure guidance method. The results of simulation and comparison in different environments show that the comprehensive performance of the fuzzy combined guidance law is better than that of other typical guidance laws, which can provide reference for the practical application of torpedo homing guidance.

Prediction of Deformation Response of Target Plate in Underwater Explosion Based on Deep Learning Neural Network

LI Zhiguo, MA Feng, ZHU Wei, JIA Xiyu, LI Yifan, CHEN Lei

2024, 32(6): 1045-1052, 1062. doi: 10.11993/j.issn.2096-3920.2024-0069

[Abstract](42) [FullText HTML] (20) [PDF 4039KB](14)

Abstract:
The deformation of a target plate in underwater explosion is manifested as a complex nonlinear coupling interaction between the structure and the fluid under the impact of shock waves. In this paper, a deep learning neural network is designed and optimized to predict the dynamic deformation displacement data of the target plate under different conditions of target plate thickness, shock factor, explosive dosage, and explosion distance. The coefficient of determination and accuracy of prediction on the test set reach 0.99 and 0.95, respectively. Compared with 25 simulation conditions, the explosion deformation response analysis graph formed by 9 261 working conditions based on the prediction model can cover a more detailed range of characteristic parameters and the trend of maximum deformation variation, providing important reference for underwater weapon design and underwater protection applications.

Temperature Adaptability Analysis of Closed Cycle Using CO₂-Based Mixed Working Fluid for Underwater Platforms

FENG Jiaqi, WANG Junpeng, CHEN Zhentao, LUO Zhengyuan, BAI Bofeng

2024, 32(6): 1053-1062. doi: 10.11993/j.issn.2096-3920.2024-0051

[Abstract](88) [FullText HTML] (79) [PDF 3174KB](20)

Abstract:
The supercritical CO₂ Brayton cycle system is an important development direction of underwater platform power technology. However, due to the low temperature in the deep sea which is far away from the critical temperature of CO₂, the cycle system has temperature adaptability problems. This paper proposed the plan to use CO₂-based mixed working fluid to improve cycle temperature adaptability and further optimize cycle performance. A simple recuperative closed cycle thermodynamic model was established, and the changes in critical parameters of CO₂-based mixed working fluid with the type and mass fraction of added gas were analyzed. The influence of the compressor inlet state parameters on the thermodynamic properties of the closed cycle of CO₂-based mixed working fluid was clarified. Besides, the influence of the pseudo-critical point position of the mixed working fluid on the pinch point and thermal inertia of the regenerator was discussed. The results show that the mixed working fluid cycle with low critical parameters can further expand the cycle temperature range and pressure ratio to improve the cycle thermodynamic performance. However, only expanding the temperature range and reducing the pressure ratio may have an adverse impact on it. Comprehensive consideration of cycle thermal efficiency, specific power, and pinch point and thermal inertia of regenerator, the maximum thermal efficiency of CO₂ + Xe(CO₂/Xe: 0.5/0.5)- transcritical Rankine cycle, CO₂ + SF₆(CO₂/SF₆: 0.9/0.1)-transcritical liquid Brayton cycle, CO₂ + SF₆(CO₂/SF₆: 0.5/0.5)-transcritical Rankine cycle can be increased by 3.79% than that of the supercritical CO₂ Breton cycle, and the maximum specific power can be increased by 31.6%. The pinch point of the regenerator is located at the cold end, which does not increase its thermal inertia and does not slow down the system response speed.

Research on Screw Propulsion Performance of Amphibious Robot

XU Pengfei, WANG Zipeng, LIN Hailong, KAI Yan, HU Qiao, SU Jianye

2024, 32(6): 1063-1071. doi: 10.11993/j.issn.2096-3920.2023-0167

[Abstract](340) [FullText HTML] (76) [PDF 7063KB](55)

Abstract:
The traditional amphibious locomotion mode mainly features the dual system of wheel or track combined with a propeller. In contrast, single-system amphibious locomotion mode has become a research hotspot in recent years because of its low system complexity and high efficiency. As a single-system amphibious locomotion mode, screw propulsion has good adaptability in semi-fluid environments such as swamp and mud flat. Over the years, there have been many research designs on its driving on land, but few studies on its driving in water. In this paper, the underwater performance of the screw propulsion device was studied, and the design method of the screw cylinder was proposed according to the principle of screw propulsion. The hydrodynamic simulation method was used to calculate the thrust of the screw cylinder at different submerged depths, and it was found that the thrust generated by the screw cylinder was the largest at 0.9 times the submerged depth. Based on the self-designed and developed amphibious robot prototype, the underwater propulsion test was carried out, and the results show that the underwater screw cylinder propulsion state is stable. In addition, the response surface method is used to optimize the design of the screw cylinder from the two aspects of screw blade height and pitch, and the optimization results can increase the propulsion efficiency by 18.2% compared with the original design scheme.

Vibration Reduction Method for Power Cabin of Torpedoes Based on Acoustic Metamaterials

SUN Xuyang, ZHOU Jingjun, WANG Qian, ZHANG Zhimin

2024, 32(6): 1072-1081. doi: 10.11993/j.issn.2096-3920.2024-0063

[Abstract](119) [FullText HTML] (34) [PDF 4455KB](38)

Abstract:
The acoustic stealth performance of torpedoes directly affects the safety of the launching platform, the concealment of the torpedo attack, and the effectiveness of wire-guided guidance. However, the current widely adopted vibration and noise reduction means show unsatisfactory effects in controlling the low and medium frequency vibration of torpedoes. In order to solve this problem, this paper investigated the vibration reduction method based on acoustic metamaterials for the power cabin of torpedoes. Firstly, the vibration response characteristics of the power cabin under axial excitation were analyzed, and a local resonance unit structure of the cantilever beam was designed. The bandgap characteristics and vibration reduction effect of the structure were analyzed. Then, for the supporting structure of the power cabin, a vibration reduction scheme based on acoustic metamaterials was proposed, and the simulation analysis finds that acoustic metamaterials have a significant inhibitory effect on vibration within the corresponding bandgap, and the attenuation of some measurement points can be as high as 11.95 dB. Finally, the validity of the vibration reduction scheme based on acoustic metamaterials is verified through tests, which provides an idea for solving the low and medium frequency vibration problem in the power cabin of the torpedo.

Research on Submarine Magnetic Field Simulation with Energized Coil

GUAN Feng, SHENG Zhaohua

2024, 32(6): 1082-1090. doi: 10.11993/j.issn.2096-3920.2024-0040

[Abstract](146) [FullText HTML] (52) [PDF 2073KB](35)

Abstract:
Due to the obvious advantages of high fidelity, adjustable magnetic field distribution and intensity, good maneuverability, low environmental dependence, and high safety of submarine magnetic field, the method of concentric magnetic field with energized coil has attracted more and more attention. It is necessary to conduct in-depth research on the distribution characteristics of the submarine magnetic field simulator with energized coil, so as to better guide its design. In this paper, the calculation methods of the spatial magnetic field of the submarine and the spatial magnetic field of arbitrary energized wire were given, and the submarine magnetic field simulation engineering scheme of the split-type three-axis orthogonal coil was proposed. The spatial magnetic field distribution characteristics of this scheme and the submarine were compared. The results show that the three-axis orthogonal coil method can simulate the spatial magnetic field distribution characteristics of a submarine well but cannot fully reflect the distribution scale, providing technical reference for submarine magnetic field simulation.

Modeling and Motion Control of Underwater Snake Robot

LI Peijuan, YANG Gang, GUO Tiezheng, LU Yang

2024, 32(6): 1091-1099. doi: 10.11993/j.issn.2096-3920.2024-0009

[Abstract](162) [FullText HTML] (51) [PDF 2074KB](30)

Abstract:
To address the autonomous swimming difficulty of an underwater snake robot in a complex underwater environment, this study designed an underwater snake robot mechanism. A kinematic model was established based on the snake motion mechanism, and a motion control method based on fuzzy control and a central pattern generator(CPG) was proposed. The CPG model was constructed by several Hopf oscillators with double-coupled chain network structure after the stability analysis of the limit cycle in a single Hopf oscillator model, and a fuzzy controller and the CPG model were introduced to form a closed-loop control network. The simulation and experiment of an underwater snake robot were carried out. The prototype can complete the experiments of linear meandering movement, left and right turning movement, and U-shaped movement. The experimental results show that the underwater snake robot not only has good stability but also can maintain superior flexibility and maneuverability in the three motion modes.

Theories and Experiments of Torpedo Shaped Charge Warhead Penetration into Water-partitioned Armor

ZHU Qifeng, LI Qin, WANG Tuanmeng, SHANG Wei, MA Hongbing

2024, 32(6): 1100-1107. doi: 10.11993/j.issn.2096-3920.2023-0148

[Abstract](95) [FullText HTML] (66) [PDF 7431KB](10)

Abstract:
To reasonably predict the penetration power of a torpedo shaped charge warhead into water-partitioned armor, a theoretical model for calculating the generated penetration depth and aperture diameters was proposed based on the A-T model and the two-step mechanism of aperture growth in combination with the penetrator penetration process analysis based on the virtual origin theory. The experiments and simulations for a reduced-scale torpedo shaped charge warhead penetration into water-partitioned armor targets were conducted, in which a single-layer aluminum plate and the spaced aluminum plates with a certain cumulative thickness were used to simulate the torpedo heads. Calculations, simulations, and experimental results were then compared and analyzed, which verified the rationality of the theoretical model. The research can provide support for the penetration power prediction and the optimization design of torpedo shaped charge warheads, as well as the technical research of new powerful torpedo shaped charge warheads to more effectively destroy the submarine protective structure.

Dynamic Characteristics of Explosive Damage to Typical Undersea Vehicles

YAN Kan

2024, 32(6): 1108-1116. doi: 10.11993/j.issn.2096-3920.2024-0139

[Abstract](50) [FullText HTML] (23) [PDF 2583KB](14)

Abstract:
This study examined the explosive damage characteristics of large undersea vehicle structures, which are crucial for improving the survivability of undersea vehicles and have far-reaching influence on tactical application and strategic deployment in naval battle. Initially, the study utilized the structured arbitrary Lagrangian-Eulerian(S-ALE) model to create models for both an undersea vehicle and underwater explosion and analyzed the characteristics of bubble motion near the wall in underwater explosion. It then investigated the structural damage characteristics of the vehicle under the influence of underwater explosion shockwaves and bubble loads. The results reveal that hydrostatic pressure amplifies the damage inflicted by explosion. Furthermore, when the undersea vehicle is exposed to attacks from two explosive charges, a greater distance between the horizontally arranged explosion sources within a certain range results in a more severe damage to the vehicle.

A High-Precision Calculation Method for Internal Trajectory of Underwater Weapon Launch

YANG Chun, LI Kaifu, CHEN Weibin, LI Lutian, LI Yinlong

2024, 32(6): 1117-1122. doi: 10.11993/j.issn.2096-3920.2023-0123

[Abstract](149) [FullText HTML] (47) [PDF 1699KB](9)

Abstract:
A high-precision calculation method for internal trajectory was proposed for the pneumatic launch system of underwater weapons. The method combined high-precision theoretical derivation with computational fluid mechanics slip technique and used the fourth-order Runge-Kutta method to solve the high-pressure gas domain during the launch process. The sliding grid was used to simulate the single degree of freedom weapon launch in the water area, so as to realize the high-precision calculation of internal trajectory, which could make up for the defects of large theoretical calculation error and high cost of fluid simulation. Through comparison with the test data, it can be seen that the average error of the discharge velocity of the weapon and the average error of the cutoff pressure of the posterior cavity obtained by this method are 5.6% and 4.0%, which proves the accuracy of this method.

Effect of Hub-to-tip Ratio on Performance of High Speed Pump-jet Propulsor for Undersea Vehicle

GAN Gongchang

2024, 32(6): 1123-1130. doi: 10.11993/j.issn.2096-3920.2024-0091

[Abstract](20) [FullText HTML] (11) [PDF 2487KB](6)

Abstract:
To investigate the influence of the hub-to-tip ratio on the high-speed pump-jet propulsors of undersea vehicles, this study took an impeller with specific speed of 1 920 as the research object and conducted numerical calculation, performance result analysis and comparison, and experimental verification of three different hub-to-tip ratios of a high-speed pump-jet propulsor for undersea vehicles. Using Fluent software, it adopted a Reynolds-averaged N-S equation and an shear stress transport k-ω model to predict the head, efficiency, and thrust of the impeller. The performance curves, cavitation performance data, and internal flow field conditions of the impeller under different hub-to-tip ratios were obtained through numerical simulation calculations. The results show that the pressure gradient on the blade surface from the blade tip to the rim decreases. With the increase in the hub-to-tip ratio, the maximum static pressure on the blade and the head and efficiency of the pump-jet propulsor all decrease, and the cavitation performance significantly declines. However, the cavitation state is superior to that at the small hub-to-tip ratio. The research findings can provide certain reference for the structure optimization design of high-speed pump-jet propulsors for undersea vehicles.

Current Status of Research on Marine Intelligent Unmanned Equipment Detection Based on Multi-Physics Fields

WANG Yuyang, JI Fang, LU Shaoqing, LI Guonan

2024, 32(6): 1131-1140. doi: 10.11993/j.issn.2096-3920.2024-0048

[Abstract](124) [FullText HTML] (28) [PDF 1355KB](52)

Abstract:
The marine intelligent unmanned equipment represented by unmanned undersea vehicles and unmanned surface vessels have the characteristics of large number, small size, high degree of intelligence, and wide range of tasks. Future naval warfare missions will use lots of marine intelligent unmanned equipment, so the detection technology of marine unmanned intelligent equipment has become one of the key technologies in the armament and scientific research of all countries. This paper provided an overview of the detection methods of marine intelligent unmanned equipment in recent years in various countries, covering the optical, electric, magnetic, and other information sources of new types of physical fields. The feasibility of multi-system collaborative detection and multi-information omnidirectional sensing techniques was analyzed, while the current research status of deep intelligent algorithm-based line-spectrum feature detection was described. In the future, the detection of marine intelligent unmanned equipment will develop towards intelligence, clustering, high precision, robustness, and timeliness, and further improving the level of underwater target recognition will be an important research direction.

Research Progress in Methods to Estimate High-resolution Direction of Arrival

ZHAO Wei, LI Xuan, HAO Chengpeng

2024, 32(6): 1141-1156. doi: 10.11993/j.issn.2096-3920.2023-0158

[Abstract](41) [FullText HTML] (18) [PDF 896KB](16)

Abstract:
With the widespread application of array signal processing, the estimation of direction of arrival(DOA) as the core problem of array signal processing has made significant progress. This paper first summarizes the traditional algorithms based on beamforming for narrowband target direction estimation relying on uniform linear arrays and emerging algorithms in the past decade. Then, it analyzes the reasons for the limited resolution of traditional beamforming-based methods and discusses higher-resolution methods such as adaptive beamforming direction spectrum, subspace methods, and compressed sensing. Furthermore, for the needs of practical applications, the paper summarizes the progress of broadband target DOA estimation methods, sparse array-based DOA estimation methods, and two-dimensional DOA estimation methods. Finally, the new advances of artificial intelligence-based methods in DOA estimation are introduced. The research in this paper can be applied to modern radar/sonar detection, radio communication, and navigation, showing high application value.

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2024, Volume 32, Issue 6

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Current Issue
2024, Volume 32, Issue 6