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    Efficient Semi-supervised Medical Image Lesion Segmentation Method Based on MedSAM
    Xi-bin JIA, Xun-jie YIN, Chao FAN, Zheng-han YANG
    Journal of Northeastern University(Natural Science)    2026, 47 (1): 1-10.   DOI: 10.12068/j.issn.1005-3026.2026.20259022
    Abstract1016)   HTML66)    PDF(pc) (1940KB)(1006)       Save

    In semi-supervised lesion segmentation, the performance of the teacher network is poor, making it difficult for it to guide the student network to perform effective segmentation. To address this issue, an efficient semi-supervised medical image lesion segmentation method was proposed, employing the medical segment anything model (MedSAM), which exhibited superior feature extraction capabilities, as the teacher network. A lightweight student network based on Mamba was constructed, and its segmentation performance was enhanced through knowledge distillation. To address the semantic mismatch caused by feature alignment across heterogeneous networks, a perturbation-consistent cross-architecture knowledge distillation method was introduced. This approach mapped teacher features to the student feature space and aligned perturbation responses, thereby improving the student network’s feature representation ability and improving segmentation performance. Additionally, to tackle the challenges of diverse lesion morphologies and low foreground-background contrast, leading to poor segmentation consistency, a distribution-based self-supervised loss was proposed for optimization. Experiments on multiple types of medical image lesion segmentation datasets demonstrate that the proposed method in this paper outperforms existing methods in segmentation performance. Meanwhile, the student network has only 1.34 M parameters, which significantly improves the model efficiency.

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    Charging and Discharging Scheduling for Electric Vehicles Based on Improved Multi-objective Chaotic Particle Swarm Optimization
    Zhi-ao CAO, Chen-shuo MA
    Journal of Northeastern University(Natural Science)    2025, 46 (9): 1-8.   DOI: 10.12068/j.issn.1005-3026.2025.20240014
    Abstract951)   HTML67)    PDF(pc) (1428KB)(428)       Save

    To address the issue of charging and discharging scheduling for EVs(electric vehicles), an orderly charging and discharging algorithm that considered users’ comprehensive satisfaction was proposed. Firstly, a large-scale orderly charging and discharging model for EVs was constructed, and users’ comprehensive satisfaction was quantified. Secondly, an improved multi-objective role partitioning chaotic particle swarm optimization(IMRPC-PSO) algorithm was proposed to solve the problems of insufficient diversity and being trapped in local optimal in traditional methods. According to the performance of particles, the roles of elite particles, general particles, and learning particles were assigned, which respectively implement diversity strategies of maintaining search, developing search, and learning search. Each particle searched the optimization space according to its assigned role. To avoid falling into local optimal, a chaotic sequence perturbation was added after the initialization of each iteration. Finally, the performance of the proposed algorithm was compared with that of the other five multi-objective optimization algorithms through case simulation. The results show that IMRPC-PSO is superior to other algorithms in solving the problem of orderly charging and discharging of EVs, verifying the effectiveness and feasibility of the proposed algorithm.

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    Defect Detection on PCB Based on Improved YOLOv8
    Zhen-zhen LYU, Li-jin FANG, Qian-kun ZHAO, Ying-cai WAN
    Journal of Northeastern University(Natural Science)    2025, 46 (10): 1-9.   DOI: 10.12068/j.issn.1005-3026.2025.20240038
    Abstract946)   HTML38)    PDF(pc) (10197KB)(160)       Save

    Due to the high integration, complex circuits, and increasing parameters of printed circuit boards (PCBs), defects in PCBs directly affect production efficiency, making computer vision-based defect detection crucial for PCB manufacturing. A self-attention-based PCB defect detection algorithm was proposed based on the YOLO object detection algorithm. First, a polarized self-attention (PSA) mechanism was introduced in the feature extraction stage to separately extract spatial and semantic features of PCBs, which were combined with input raw features to enhance the network’s feature representation capability. Then, a small-object detection head was added in the decoding stage, which fully utilized low-resolution features from the YOLO network Backbone module to enable the network to focus on local details of PCBs and improve defect positioning accuracy. Experiments show that the proposed method achieves 95.5% accuracy on the PCB dataset, 4% higher than the original YOLOv8 method, with the mAP0.5∶0.95 metric increased by 2.8%.

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    Risk-Oriented Crowd Navigation Strategy Based on Deep Reinforcement Learning
    Yang JIANG, Tian-xiang ZHAO, Ruo-huai SUN, Lei WANG
    Journal of Northeastern University(Natural Science)    2025, 46 (12): 1-8.   DOI: 10.12068/j.issn.1005-3026.2025.12.20240094
    Abstract822)   HTML25)    PDF(pc) (2715KB)(508)       Save

    To improve robot freezing and suboptimal performance of traditional navigation methods in the presence of dynamic obstacles, a navigation method based on deep reinforcement learning was proposed. The core of this method lies in its risk perception module and path selection module. The risk perception module calculated the collision probability between the robot and nearby dynamic obstacles in real time, allowing the robot to prioritize avoiding more hazardous obstacles. Concurrently, the path selection module evaluated the “passing ability” of the robot in surrounding areas in real time, guiding the robot to choose safer paths. In comparison experiments with a deep reinforcement learning method that lacks these modules, the proposed method achieved the highest navigation success rate in all simulation test environments, with an improvement rate of up to 11%.

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    Learning-Based NSGA-Ⅱ for Multi-objective Portfolio Optimization Problems
    Zhu ZHU, Hang-yu LOU
    Journal of Northeastern University(Natural Science)    2025, 46 (9): 17-24.   DOI: 10.12068/j.issn.1005-3026.2025.20249030
    Abstract806)   HTML10)    PDF(pc) (1542KB)(1386)       Save

    To address the issues of insufficient diversity and poor constraint-handling capability in the non-dominated sorting genetic algorithm Ⅱ (NSGA-Ⅱ) when solving portfolio optimization problems, a learning-based improved NSGA-Ⅱ algorithm (INSGA-Ⅱ) incorporating clustering and an adaptive feasibility repair strategy for multi-objective portfolio optimization was proposed. In the proposed algorithm, clustering learning was employed to enhance population diversity, while adaptive repair ensured that newly generated solutions were feasible, thereby improving the algorithm's diversity and convergence speed. Additionally, the populations after crossover and mutation were preserved separately and merged with the parent population to increase the selection pressure and quality of offspring generation. Experimental results demonstrate that the proposed algorithm exhibits superior search performance and stability, effectively solving multi-objective portfolio optimization problems.

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    An Improved Small Object Detection Model Based on YOLOv8 for UAV Vision
    Ji-hong LIU, Rui-rui SHI
    Journal of Northeastern University(Natural Science)    2025, 46 (12): 29-37.   DOI: 10.12068/j.issn.1005-3026.2025.20240116
    Abstract799)   HTML24)    PDF(pc) (10174KB)(1689)       Save

    In view of easy false detection and missed detection of small objects in unmanned aerial vehicle (UAV) aerial images, as well as the requirements for real-time performance and lightweight design in UAV detection tasks, an improved lightweight and efficient model based on YOLOv8 was proposed. Firstly, the Neck part of YOLOv8 was simplified into a feature pyramid network, enabling the model to effectively utilize the detailed information extracted by shallow networks. Meanwhile, a feature fusion module was added to provide more favorable features for small object detection to the Head layer. Secondly, an efficient local attention (ELA) mechanism was integrated into the Backbone part to achieve accurate localization of target regions. Experimental results show that compared with YOLOv8s, the parameters and model size of the improved model are reduced by 50%, while the mAP0.5 and detection speed are improved by 4%. This improved model provides a new idea for the deployment of UAV detection.

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    Design of Nonlinear Observer for Distributed Drive Electric Vehicle with Actuator Faults
    Hong-wei WANG, Xin-yu JI, Jin-shuo SONG
    Journal of Northeastern University(Natural Science)    2026, 47 (1): 60-66.   DOI: 10.12068/j.issn.1005-3026.2026.20240152
    Abstract787)   HTML12)    PDF(pc) (1352KB)(167)       Save

    A robust fault diagnosis algorithm based on an observer was designed for the nonlinear dynamic system of distributed drive electric vehicles with actuator faults. Firstly, by considering the actuator fault and system disturbance, a mathematical model of 7 degrees of freedom vehicle system was established. Then, a fault diagnosis strategy based on a nonlinear observer was designed by using linear matrix inequality and Lyapunov function to realize multiple estimations of system state, disturbance information, and fault factor, and the relevant theoretical proof was given. Finally, by referring to the actual driving conditions of the vehicle, the co-simulation was carried out by MATLAB/Simulink and CarSim. The results show that the designed observer can accurately diagnose and estimate the actuator faults, rapidly track the actual operating state of the system, and improve the anti-interference ability of the system.

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    Prediction Model of BiGRU-Att Sinter Drum Index Based on Hybrid Feature Selection
    Xiao-tong LI, Xiao-long SONG, Jin-xin FAN, Zhao-xia WU
    Journal of Northeastern University(Natural Science)    2026, 47 (1): 107-114.   DOI: 10.12068/j.issn.1005-3026.2026.20240127
    Abstract753)   HTML6)    PDF(pc) (1515KB)(127)       Save

    Because the sintering process has complex and high-dimensional process variables and many uncertain factors, it is difficult for a single feature selection method to effectively select the best feature set, which affects the prediction accuracy of the model. Therefore, a prediction model of attention mechanism-based bidirectional gated recurrent unit model (BiGRU-Att) sinter drum index based on hybrid feature selection was proposed. Firstly, the maximum information coefficient (MIC) was used to select candidate features from the original feature set. Then, the feature selection method based on simultaneous perturbation stochastic approximation (SPSA-FS) was used to further optimize the candidate feature set. Finally, the best feature set was used as the input of BiGRU-Att to predict the sinter drum index. The results of comparative analysis with multiple models and single feature selection methods show that the hybrid feature selection method proposed in this paper can select the best feature set, and the established model has higher prediction accuracy, providing reliable decision-making support for the sintering process.

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    Two-Stage SiamCAR Tracking Algorithm Combining Motion Information and Dual-attention Mechanism
    Ying WEI, Jia-peng ZHANG, Jia-qi CUI, Tong HUANG
    Journal of Northeastern University(Natural Science)    2025, 46 (9): 9-16.   DOI: 10.12068/j.issn.1005-3026.2025.20240018
    Abstract744)   HTML14)    PDF(pc) (2509KB)(169)       Save

    In single-object tracking, the accuracy of the tracking bounding box is often compromised by factors such as deformation, motion blur, occlusion, and background interference. In particular, background interference frequently leads to tracking hopping and drift. To mitigate these issues, a two-stage tracking algorithm that integrated motion information with a dual-attention mechanism was proposed. In the first stage, a SiamCAR tracker with a dual-attention mechanism was employed to coarsely locate the target in the current frame. In the second stage, a refinement module of the bounding box was constructed using pixel-level similarity computations to learn the subtle features of the target under low-latency conditions, thereby enhancing the tracking accuracy. Finally, the tracking box obtained based on appearance features was fused with the target’s motion trajectory information to mitigate tracking drift and hopping. Experimental results on the OTB100 dataset indicate that the success rate and accuracy of the tracking box have improved by 4.6% and 2.8%, respectively, compared to the original. The success rate in the presence of background interference has reached 69.6%.

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    Application of Mean Teacher Method in Semi-supervised Medical Image Segmentation
    Jin-zhu YANG, Mei WEI, Qi YU, Song SUN
    Journal of Northeastern University(Natural Science)    2026, 47 (1): 20-30.   DOI: 10.12068/j.issn.1005-3026.2026.20250103
    Abstract736)   HTML16)    PDF(pc) (1174KB)(253)       Save

    Medical image segmentation is an important technical basis for clinical diagnosis and treatment. Accurate medical image segmentation contributes to improving the accuracy and efficiency of disease diagnosis. Deep learning methods have made significant progress in this field. However, these methods are heavily dependent on manually labeled data, and the high cost of obtaining high-quality segmentation labels limits their practical application. Semi-supervised learning effectively alleviates the label scarcity problem by combining a small amount of labeled data with a large amount of unlabeled data. Mean teacher (MT) is a mainstream semi-supervised learning method. It leverages an exponential moving average to extract information from unlabeled data, enhancing model accuracy and generalization performance. Currently, MT has been widely adopted in medical image segmentation. In this paper, MT was comprehensively reviewed, focusing on its application and improvement in the medical image segmentation field from aspects such as consistency regularization, uncertainty, attention mechanism, multi-task learning, auxiliary correction, and model variants. Furthermore, trends in the application and enhancement of MT were briefly analyzed, and commonly used comparative experimental methods, datasets, backbone networks of MT, and evaluation metrics in medical image segmentation were summarized. Finally, existing challenges and potential future research directions in applying MT to medical image segmentation were discussed.

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    Study on Gas Production Characteristics and Kinetics of Coal and Biomass Co-gasification Under CO2 Atmosphere
    Xi-wen YAO, Hong-bai ZHANG, Kai-li XU, Lei-lei ZHANG
    Journal of Northeastern University(Natural Science)    2025, 46 (12): 124-131.   DOI: 10.12068/j.issn.1005-3026.2025.20240150
    Abstract727)   HTML12)    PDF(pc) (2199KB)(253)       Save

    A controlled-atmosphere tube furnace was used to study the gas production and reaction kinetics of coal and biomass during gasification under CO2 atmosphere. It is found that the pyrolysis of coal and biomass under N2 atmosphere is divided into three stages: dehydration (30~210 ℃), rapid pyrolysis (210~400 ℃), and slow pyrolysis (400~1 000 ℃). Gasification under CO2 atmosphere is divided into four stages: dehydration (30~210 ℃), volatile release (210~400 ℃), slow weight loss (400~660 ℃), and Boudouard reaction (660~1 000 ℃). The gasification conversion rate under CO2 atmosphere is about 85%, which is higher than that under N2 atmosphere (53%). The gasification reaction under CO2 atmosphere requires higher activation energy than that under N2 atmosphere, but the reaction rate is faster. The gases produced by the gasification of coal and biomass under CO2 atmosphere mainly include CO, CO2, CH4, and H2. At 800 ℃, CO gas is regenerated, indicating that CO2 has a Boudouard reaction with carbon as an oxidant at high temperatures. CO2 inhibits the formation of CH4, H2, and C m H n, which contain hydrogen and gases with high calorific values.

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    3D Gesture Estimation Algorithm Based on Geometric Attention Mechanism
    Hui ZOU, Li-huang SHE, Ye-han CHEN, Yi YUE
    Journal of Northeastern University(Natural Science)    2025, 46 (10): 44-50.   DOI: 10.12068/j.issn.1005-3026.2025.20240079
    Abstract722)   HTML8)    PDF(pc) (2154KB)(77)       Save

    A gesture recognition network based on the coding and decoding infrastructure of Transformer was designed, and an optimized offset attention mechanism was introduced to extract hand features based on the self-attention mechanism. At the same time, in order to extract the local features of the hand structure better, a neighborhood aggregation strategy was designed. The three-dimensional (3D) complexity of the hand structure itself led to different levels of smoothness in different regions. When estimating gestures, ignoring this feature usually leads to the loss of local key information of the hand structure. In order to solve this problem, geometric decomposition of the hand structure was carried out, and sharp and flexible components were used to represent the sharp and flat regions of the hand structure, respectively. Different attention was paid to the characteristics of these two components through the attention mechanism. Experiments on MSRA, ICVL, and NYU datasets demonstrate that the accuracy of this algorithm is comparable to that of SOTA.

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    LIDD-Net: Lightweight Industrial Product Defect Detection Method Based on Deep Learning
    Xiao-peng SHA, De-han XIE, Zhou-peng GUO, Kai SUN
    Journal of Northeastern University(Natural Science)    2025, 46 (10): 18-26.   DOI: 10.12068/j.issn.1005-3026.2025.20240058
    Abstract710)   HTML10)    PDF(pc) (2555KB)(341)       Save

    In industrial products, various types of defects often exhibit high inter-class similarity, large scale variations, and complex backgrounds. To address these challenges, a lightweight industrial defect detection network (LIDD-Net) was proposed. To handle highly similar defect types, in LIDD-Net, a channel interaction separation backbone network was introduced, which enhanced feature extraction while reducing the computational cost of the model. To address multi-scale defect variations, a lightweight feature fusion network was developed, namely RepGhostPAN, to efficiently integrate multi-scale features in the image and accelerate inference. For complex detection backgrounds, a lightweight auxiliary training module was proposed, leveraging an auxiliary training head and a dynamic soft label assignment strategy to better distinguish target defects from complex backgrounds. Experiments on steel, aluminum, and tire defect datasets demonstrate that LIDD-Net achieves mAP@0.5 scores of 98.3%, 98.1%, and 96.1%, respectively, with only 0.62×106 parameters, meeting practical industrial requirements.

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    Visual Simulation of Bone Cement Injection Process for Vertebroplasty
    Ya-lan ZHANG, Long SHEN, Shao-fu ZHANG, Xue-song ZHANG
    Journal of Northeastern University(Natural Science)    2026, 47 (1): 52-59.   DOI: 10.12068/j.issn.1005-3026.2026.20259021
    Abstract710)   HTML10)    PDF(pc) (7483KB)(287)       Save

    Determining key injection parameters of bone cement, such as volume, pressure and angle, in percutaneous vertebroplasty still largely relies on empirical judgment, and they have a critical role in preventing leakage and related complications. An advanced simulation framework that integrated a multiphase non-Newtonian fluid model was introduced. The framework employed a Voronoi-based biomimetic bone representation to predict cement flow behavior within trabecular structures, enabling high-fidelity visualization and analysis of cement dispersion under varying operating conditions. Experimental results demonstrate the framework’s potential value in preoperative planning optimization, surgical training assistance, and leakage risk assessment. For preoperative use, it can assist clinicians in rehearsing injection procedures and refining operation strategies; in training scenarios, it can simulate cement dispersion patterns under different parameter settings, thereby helping novice surgeons understand procedural logic; furthermore, its capability to predict leakage risks holds promise for providing technical support to improve clinical surgical safety.

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    Joint Optimization Approach for Medical Image Compression and Vision Tasks
    Chao YAO, Zi-xuan GAO, Jun-ru CHEN, Yi-peng LU
    Journal of Northeastern University(Natural Science)    2026, 47 (1): 11-19.   DOI: 10.12068/j.issn.1005-3026.2026.20259020
    Abstract710)   HTML32)    PDF(pc) (2103KB)(412)       Save

    In medical image processing, the reliance on independent encoding components makes it impossible to achieve joint optimization of data compression and machine vision tasks. To address this issue, an end-to-end machine vision task-driven medical image compression network (MVMICNet) was proposed, achieving harmonious unification of data compression and medical image analysis in an end-to-end manner. To maintain the performance of machine vision tasks before and after medical image compression, a task-aware improved code rate-accuracy loss function was designed. By introducing task-related loss terms, it dynamically balanced the relationship among code rate, reconstructed image distortion, and machine vision task accuracy during the optimization process. Furthermore, the MVMICNet model adopted a stage-wise training approach, specifically optimizing for the different characteristics of machine vision tasks to ensure that the model can accurately capture the feature information crucial for diagnosis. This has achieved a simultaneous improvement in compression efficiency and task performance, thus demonstrating superior robustness in complex medical application scenarios. Finally, the effectiveness of the framework was verified in semantic segmentation and object detection tasks.

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    Microstructure and Mechanical Properties of Medium Carbon Steel with Ultrafine-Grained Ferrite-Pearlite Lamellar Structure
    Hao WEI, Yang ZHANG, Xiao-ning XU, Qi-bin YE
    Journal of Northeastern University(Natural Science)    2025, 46 (9): 81-86.   DOI: 10.12068/j.issn.1005-3026.2025.20240048
    Abstract709)   HTML9)    PDF(pc) (12261KB)(69)       Save

    Using the warm rolling process in the two-phase region,ultrafine-grained ferrite-pearlite lamellar microstructures were obtained in a 0.41%C medium carbon steel. The microstructures and mechanical properties of the warm rolled steel sheets were characterized using scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),quasi-static tensile tests,and a series of low-temperature impact tests at three different temperatures(770,800 and 830 ℃)for comparative analysis. The results reveal that in the steel sheets rolled at temperatures of 770,800,and 830 ℃,the average grain size of ferrite is measured to be 0.82,0.89,and 1.14 μm,the proportion of pearlite is 16.4%,36.2%,43.5%,with the size of 0.9,1.3,1.8 μm,respectively. Furthermore, the yield strength is(696±3),(733±7)and(776±5)MPa,the elongation after fracture is 16.5%,16.1% and 13.8%,and the impact energy at -60 °C is 119,114,and 89 J,respectively.The proportion and size of ultrafine-grained ferrite-pearlite in the lamellar structure of medium carbon steel can be changed by warm rolling at different temperatures in the two-phase region.As a result, a remarkable improvement in the low-temperature impact toughness of the medium carbon steel with high pearlite content is achieved. This leads to a synergistic enhancement of strength, ductility, and low-temperature impact toughness.

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    Multi-step Prediction of Sintering Terminal Point Based on PBT-DeepTCN and Digital Twin
    Xiao-long SONG, Xiao-tong LI, Huan YANG, Zhao-xia WU
    Journal of Northeastern University(Natural Science)    2026, 47 (1): 99-106.   DOI: 10.12068/j.issn.1005-3026.2026.20240126
    Abstract700)   HTML2)    PDF(pc) (2605KB)(173)       Save

    The position of the sintering terminal point is a key parameter that affects the quality and production efficiency of sinter. To improve insufficient guidance, poor timeliness, and weak visualization effect in sintering terminal point prediction, a five-dimensional digital twin model was constructed, including physical entity, virtual environment, multi-step prediction, twin data, and virtual and real connection, which provided process parameter monitoring and optimization guidance for the sintering process. In terms of prediction, the data was first preprocessed, and then the feature variables were screened by grey relation analysis (GRA). Finally, the deep temporal convolutional network (DeepTCN)by using population based training(PBT) was constructed for multi-step prediction of the sintering terminal point. The experimental results show that the proposed digital twin model has high prediction accuracy under different prediction steps, and it provides advanced ideas and technical methods for digital and intelligent transformation in the sintering field.

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    Effect of Vibration of Side Dam on Solidification Inside Melt Pool of Twin-Roll Thin Strip Casting
    Xuan-xuan LI, En JIANG, Gang LIU, Xian-zhong HU
    Journal of Northeastern University(Natural Science)    2026, 47 (1): 123-130.   DOI: 10.12068/j.issn.1005-3026.2026.20240139
    Abstract697)   HTML1)    PDF(pc) (2631KB)(64)       Save

    A numerical simulation was conducted to investigate the solidification characteristics inside the melt pool during twin-roll thin strip casting under side dam vibration. The effects of vibration frequency, amplitude, and casting temperature on molten steel solidification in the melt pool were analyzed. The mechanical vibration experiment was designed to validate the accuracy of the numerical model. Results show that applying vibration accelerates molten metal solidification rate, and higher vibration frequency further enhances the solidification rate. Due to the high heat flux density at the side dam, the solidification rate of the molten steel increases, leading to a decreasing trend in liquid fraction from the side dam to the center of the melt pool along the horizontal direction. Elevated casting temperature reduces the melt pool’s mushy zone size and lowers the Kiss point position. The study finds that the optimal vibration frequency is 13 Hz, the optimal amplitude is 0.5 mm, and the casting temperature should not exceed 1 860 K.

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    Distributed Resilient Control of DC Microgrid Under False Data Injection Attack
    Yuan-zheng TAI, Fan-wei MENG, Yu ZHANG
    Journal of Northeastern University(Natural Science)    2026, 47 (1): 67-74.   DOI: 10.12068/j.issn.1005-3026.2026.20240146
    Abstract676)   HTML4)    PDF(pc) (2243KB)(142)       Save

    In order to solve the problem of voltage deviation and current distribution imbalance in direct current (DC) microgrid under false data injection attack, a distributed resilient cooperative control method was proposed by taking the islanded DC microgrid with multiple distributed generators as the research object. This method could effectively eliminate the impact of false data injection attacks and will not interfere with the operation of the system under normal circumstances. The Lyapunov stability theory was used to prove that the DC microgrid can operate stably when it is attacked by any constant false data injection, achieving the two control objectives of voltage regulation and current distribution. The simulation model was built by MATLAB/Simulink, and the validity of the control method was verified.

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    Study on Multiphase Flow and Homogenization Behavior During Rare Earth Alloying of Molten Steel
    Yun-long HAO, Qing-hua XIE, Pei-yuan NI, Ying LI
    Journal of Northeastern University(Natural Science)    2025, 46 (9): 73-80.   DOI: 10.12068/j.issn.1005-3026.2025.20240046
    Abstract670)   HTML6)    PDF(pc) (2069KB)(93)       Save

    In order to study the behavior during the mass transfer and homogenization in the molten pool by argon blowing at the bottom of the ladle in the refining process, a LES-DPM-VOF coupled numerical model for a 150 t ladle in a steel plant was established to simulate slag-steel-argon three phase flow, and the effects of argon blowing rates on multiphase flow behavior of slag-steel-argon and the homogenization phenomenon of liquid steel were studied. The results show that the shape of the slag hole predicted by the numerical model is in good agreement with experimental observations. When the blowing rate is 50 L/min, the maximum velocity of molten steel in the ladle is about 0.7 m/s, and the slag-steel interface only shows a little fluctuation without the formation of a slag hole. As the blowing rate increases from 50 L/min to 100 L/min, the lifting effect of bubbles on molten steel is enhanced, and the maximum upward velocity of molten steel increases from 0.7 m/s to 1.07 m/s. In addition, the fluctuation of the slag-steel interface increases. Furthermore, the study on homogenization behavior shows that the homogenization time of the alloy is inversely proportional to the argon blowing rate. When the diameter of the simulated alloy is 20 cm and the blowing rate is 50 L/min, the homogenization time is 245 s. When the blowing rate increases to 300 L/min, the homogenization time decreases to 145 s.

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