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Stealth Aircraft Penetration Trajectory Planning in 3D Complex Dynamic Based on Radar Valley Radius and Turning Maneuver 基于雷达波谷半径和转弯操纵的隐形飞机三维复杂动态穿透轨迹规划
IF 2.6 3区 工程技术 Q2 Engineering Pub Date : 2024-05-16 DOI: 10.3390/aerospace11050402
Xiaoqiang Lu, Jun Huang, Jingxin Guan, Lei Song
Based on the quasi-six-degree-of-freedom flight dynamic equations, considering the changes in the elevation angle caused by an increase in the rolling angle during maneuvering turns, which leads to a rise in the radar cross-section. A computational model for the radar detection probability of aircraft in complex environments was constructed. By comprehensively considering flight parameters such as turning angle, rolling angle, Mach number, and radar power factor, this study quantitatively analyzed the influence of these factors on the radar detection probability. It revealed the variation patterns of radar detection probability under different flight conditions. The results provide theoretical support for the Radar Valley Radius and Turning Maneuver Method (RVR-TM) based on decision trees, and lay the foundation for the development of subsequent intelligent decision-making models. To further optimize the trajectory selection of aircraft in complex environments, this study combines theoretical analysis with reinforcement learning algorithms to establish an intelligent decision-making model. This model is trained using the Proximal Policy Optimization (PPO) algorithm, and through precisely defining the state space and reward functions, it accomplishes intelligent trajectory planning for stealth aircraft under radar threat scenarios.
基于准六自由度飞行动态方程,考虑到机动转弯时滚动角增加引起的仰角变化,从而导致雷达截面上升。构建了复杂环境下飞机雷达探测概率的计算模型。通过综合考虑转弯角、滚转角、马赫数、雷达功率因数等飞行参数,定量分析了这些因素对雷达探测概率的影响。研究揭示了不同飞行条件下雷达探测概率的变化规律。研究结果为基于决策树的雷达波谷半径和转弯机动法(RVR-TM)提供了理论支持,为后续智能决策模型的开发奠定了基础。为了进一步优化飞机在复杂环境中的轨迹选择,本研究将理论分析与强化学习算法相结合,建立了一个智能决策模型。该模型采用近端策略优化(PPO)算法进行训练,通过精确定义状态空间和奖励函数,完成雷达威胁场景下隐身飞机的智能轨迹规划。
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引用次数: 0
Accurate Satellite Operation Predictions Using Attention-BiLSTM Model with Telemetry Correlation 利用具有遥测相关性的注意力-BiLSTM 模型准确预测卫星运行情况
IF 2.6 3区 工程技术 Q2 Engineering Pub Date : 2024-05-15 DOI: 10.3390/aerospace11050398
Yi Peng, ShuZe Jia, Lizi Xie, Jian Shang
In satellite health management, anomalies are mostly resolved after an event and are rarely predicted in advance. Thus, trend prediction is critical for avoiding satellite faults, which may affect the accuracy and quality of satellite data and even greatly impact safety. However, it is difficult to predict satellite operation using a simple model because satellite systems are complex and telemetry data are copious, coupled, and intermittent. Therefore, this study proposes a model that combines an attention mechanism and bidirectional long short-term memory (attention-BiLSTM) with telemetry correlation to predict satellite behaviour. First, a high-dimensional K-nearest neighbour mutual information method is used to select the related telemetry variables from multiple variables of satellite telemetry data. Next, we propose a new BiLSTM model with an attention mechanism for telemetry prediction. The dataset used in this study was generated and transmitted from the FY3E meteorological satellite power system. The proposed method was compared with other methods using the same dataset used in the experiment to verify its superiority. The results confirmed that the proposed method outperformed the other methods owing to its prediction precision and superior accuracy, indicating its potential for application in intelligent satellite health management systems.
在卫星健康管理中,异常情况大多在事件发生后才得到解决,很少能提前预测。因此,趋势预测对于避免卫星故障至关重要,因为卫星故障可能会影响卫星数据的准确性和质量,甚至对安全造成重大影响。然而,由于卫星系统复杂,遥测数据量大、耦合性强、时断时续,因此很难用一个简单的模型来预测卫星的运行情况。因此,本研究提出了一种将注意力机制和双向长短期记忆(attention-BiLSTM)与遥测相关性相结合的模型来预测卫星行为。首先,使用高维 K 近邻互信息方法从卫星遥测数据的多个变量中选择相关的遥测变量。接着,我们提出了一种具有注意力机制的新型 BiLSTM 模型,用于遥测预测。本研究使用的数据集由 FY3E 气象卫星电源系统生成并传输。为了验证所提方法的优越性,我们使用实验中使用的相同数据集将所提方法与其他方法进行了比较。结果证实,所提方法的预测精度和准确性优于其他方法,表明其在智能卫星健康管理系统中的应用潜力。
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引用次数: 0
Beyond Static Obstacles: Integrating Kalman Filter with Reinforcement Learning for Drone Navigation 超越静态障碍:将卡尔曼滤波器与强化学习整合用于无人机导航
IF 2.6 3区 工程技术 Q2 Engineering Pub Date : 2024-05-15 DOI: 10.3390/aerospace11050395
Francesco Marino, Giorgio Guglieri
Autonomous drones offer immense potential in dynamic environments, but their navigation systems often struggle with moving obstacles. This paper presents a novel approach for drone trajectory planning in such scenarios, combining the Interactive Multiple Model (IMM) Kalman filter with Proximal Policy Optimization (PPO) reinforcement learning (RL). The IMM Kalman filter addresses state estimation challenges by modeling the potential motion patterns of moving objects. This enables accurate prediction of future object positions, even in uncertain environments. The PPO reinforcement learning algorithm then leverages these predictions to optimize the drone’s real-time trajectory. Additionally, the capability of PPO to work with continuous action spaces makes it ideal for the smooth control adjustments required for safe navigation. Our simulation results demonstrate the effectiveness of this combined approach. The drone successfully navigates complex dynamic environments, achieving collision avoidance and goal-oriented behavior. This work highlights the potential of integrating advanced state estimation and reinforcement learning techniques to enhance autonomous drone capabilities in unpredictable settings.
自主无人机在动态环境中具有巨大的潜力,但它们的导航系统往往在移动障碍物面前举步维艰。本文结合交互式多重模型(IMM)卡尔曼滤波器和近端策略优化(PPO)强化学习(RL),提出了在这种情况下进行无人机轨迹规划的新方法。IMM 卡尔曼滤波器通过对运动物体的潜在运动模式进行建模,解决了状态估计难题。这样,即使在不确定的环境中,也能准确预测未来物体的位置。然后,PPO 强化学习算法利用这些预测来优化无人机的实时轨迹。此外,PPO 能够处理连续的动作空间,因此非常适合安全导航所需的平滑控制调整。我们的模拟结果证明了这种组合方法的有效性。无人机成功地在复杂的动态环境中导航,实现了避免碰撞和以目标为导向的行为。这项工作凸显了整合先进状态估计和强化学习技术的潜力,以增强无人机在不可预测环境中的自主能力。
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引用次数: 0
Investigation of High-Speed Rubbing Behavior of GH4169 Superalloy with SiC/SiC Composites 用碳化硅/碳化硅复合材料研究 GH4169 超合金的高速摩擦行为
IF 2.6 3区 工程技术 Q2 Engineering Pub Date : 2024-05-15 DOI: 10.3390/aerospace11050397
Zhaoguo Mi, Kanghe Jiang, Yicheng Yang, Zhenhua Cheng, Weihua Yang, Zhigang Sun
The silicon carbide fiber-reinforced silicon carbide matrix (SiC/SiC), ceramic matrix composite (CMC) and nickel-based superalloy GH4169 can be utilized in high-temperature applications due to their high-temperature performance. The SiC/SiC composites are commonly used in turbine outer rings, where they encounter friction and wear against the turbine blades. This high-speed rubbing occurs frequently in aircraft engines and steam turbines. To investigate the tribological behavior of these materials, rubbing experiments were conducted between the SiC/SiC and the GH4169 superalloy. The experiments involved varying the blade tip speeds ranging from 100 m/s to 350 m/s and incursion rates from 5 μm/s to 50 μm/s at room temperature. Additionally, experiments were conducted at high temperatures to compare the tribological behavior under ambient conditions. The results indicated that the GH4169 superalloy exhibited abrasive furrow wear during rubbing at both room temperature and high temperature. Furthermore, at elevated temperatures, some of the GH4169 superalloy adhered to the surface of the SiC/SiC. The analysis of the experiments conducted at ambient temperatures revealed that the friction coefficient increased with higher blade tip velocities (100~350 m/s). However, the coefficient was lower at high temperatures compared to room temperature. Furthermore, significant temperature increases were observed during rubbing at room temperature, whereas minimal temperature changes were detected on the rubbing surface at high temperatures.
碳化硅纤维增强碳化硅基复合材料(SiC/SiC)、陶瓷基复合材料(CMC)和镍基超合金 GH4169 具有高温性能,可用于高温应用领域。SiC/SiC 复合材料通常用于涡轮外环,因为它们会与涡轮叶片发生摩擦和磨损。这种高速摩擦经常发生在航空发动机和蒸汽轮机中。为了研究这些材料的摩擦学行为,我们在 SiC/SiC 和 GH4169 超级合金之间进行了摩擦实验。实验包括在室温下改变叶片尖端速度,从 100 米/秒到 350 米/秒不等,侵入率从 5 微米/秒到 50 微米/秒不等。此外,还在高温条件下进行了实验,以比较在环境条件下的摩擦学行为。结果表明,在室温和高温条件下,GH4169 超耐热合金在摩擦过程中都会出现磨沟磨损。此外,在高温条件下,部分 GH4169 超耐热合金附着在 SiC/SiC 表面。在常温下进行的实验分析表明,摩擦系数随着叶尖速度(100 至 350 米/秒)的提高而增大。然而,与室温相比,高温下的摩擦系数较低。此外,在室温下摩擦过程中观察到温度明显升高,而在高温下摩擦表面的温度变化极小。
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引用次数: 0
A High Step-Down SiC-Based T-Type LLC Resonant Converter for Spacecraft Power Processing Unit 用于航天器动力处理单元的基于碳化硅的高降压 T 型 LLC 谐振转换器
IF 2.6 3区 工程技术 Q2 Engineering Pub Date : 2024-05-15 DOI: 10.3390/aerospace11050396
Wenjie Ma, Hui Li
A spacecraft power processing unit (PPU) is utilized to convert power from solar arrays or electric batteries to the payload, including electric propulsion, communication equipment, and scientific instruments. Currently, a high-voltage converter is widely applied to the spacecraft PPU to improve power density and save launch weight. However, the high voltage level poses challenges such as high step-down ratios and high power losses. To achieve less conduction loss, a SiC-based T-type three-level (TL) LLC resonant converter is proposed. To further broaden the gain range and achieve high step-down ratios, a variable frequency and adjustable phase-shift (VFAPS) modulation scheme is proposed. Meanwhile, the steady-state time-domain model is established to elaborate the operation principles and boundary conditions for soft switching. Furthermore, the optimal resonant element design considerations have been elaborated to achieve wider gain range and facilitate easier soft switching. Furthermore, the numerical solutions for switching frequency and phase shift (PS) angle under each specific input could be figured out. Finally, the effectiveness of this theoretical analysis is demonstrated via a 500-W experimental prototype with 650∼950-V input and constant output of 48-V/11-A.
航天器电源处理单元(PPU)用于将太阳能电池阵列或蓄电池的电能转换为有效载荷,包括电力推进、通信设备和科学仪器。目前,高电压转换器被广泛应用于航天器功率处理单元,以提高功率密度并减轻发射重量。然而,高电压水平带来了高降压比和高功率损耗等挑战。为了减少传导损耗,我们提出了一种基于 SiC 的 T 型三电平(TL)LLC 谐振转换器。为了进一步拓宽增益范围并实现高降压比,提出了一种可变频率和可调相移(VFAPS)调制方案。同时,建立了稳态时域模型,阐述了软开关的工作原理和边界条件。此外,还阐述了最佳谐振元件设计考虑因素,以实现更宽的增益范围和更简便的软开关。此外,还可以计算出每种特定输入下的开关频率和相移(PS)角的数值解。最后,通过一个 500 瓦的实验原型(输入电压为 650∼950V,恒定输出电压为 48V/11-A)证明了这一理论分析的有效性。
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引用次数: 0
Improved A* Algorithm for Path Planning Based on CubeSats In-Orbit Electromagnetic Transfer System 基于立方体卫星在轨电磁传输系统的改进型 A* 路径规划算法
IF 2.6 3区 工程技术 Q2 Engineering Pub Date : 2024-05-15 DOI: 10.3390/aerospace11050394
Duo Xu, Honghao Yue, Yong Zhao, Fei Yang, Jun Wu, Xueting Pan, Tao Tang, Yuhao Zhang
For future large-scale CubeSat applications in orbit, the deployer must accommodate a greater number of CubeSats and facilitate cluster releases. This paper introduces an improved A* algorithm tailored for CubeSat in-orbit transfer path planning. Unlike the traditional A* algorithm, this enhanced version incorporates a path coordination strategy to manage congestion caused by the simultaneous transfer of many CubeSats, ensuring they reach their designated release positions smoothly and thus significantly boosting the efficiency of CubeSat transfers. Additionally, the algorithm develops a cost model for attitude disturbances on the electromagnetic conveying platform and crafts an improved cost function. It strategically balances the reduction in attitude disturbances caused by CubeSat transfers with the efficiency of these transfers. The primary goal is to minimize platform disturbances while optimizing the number of steps CubeSats need to reach their intended positions. The effectiveness of this algorithm is demonstrated through detailed case studies, which confirm that during the CubeSat transfer process, the platform’s attitude remains stable, and the transfer efficiency is well-managed, achieving efficient path planning for the in-orbit transfer of numerous CubeSats.
对于未来在轨的大规模立方体卫星应用,部署器必须能够容纳更多的立方体卫星,并为集群释放提供便利。本文介绍了一种为立方体卫星在轨转移路径规划量身定制的改进型 A* 算法。与传统的A*算法不同,该增强版算法纳入了路径协调策略,以管理多颗立方体卫星同时转移所造成的拥堵,确保它们顺利到达指定的释放位置,从而显著提高立方体卫星转移的效率。此外,该算法还开发了电磁传送平台姿态干扰成本模型,并制作了改进的成本函数。该算法在减少立方体卫星转移造成的姿态干扰和提高转移效率之间实现了战略性平衡。其主要目标是最大限度地减少平台干扰,同时优化立方体卫星到达预定位置所需的步数。详细的案例研究证明了该算法的有效性,证实在立方体卫星转移过程中,平台姿态保持稳定,转移效率得到良好管理,实现了众多立方体卫星在轨转移的高效路径规划。
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引用次数: 0
Enhancing Small Object Detection in Aerial Images: A Novel Approach with PCSG Model 增强航空图像中的小物体检测:利用 PCSG 模型的新方法
IF 2.6 3区 工程技术 Q2 Engineering Pub Date : 2024-05-14 DOI: 10.3390/aerospace11050392
Kang An, Huiping Duanmu, Zhiyang Wu, Yuqiang Liu, Jingzhen Qiao, Qianqian Shangguan, Yaqing Song, Xiaonong Xu
Generalized target detection algorithms perform well for large- and medium-sized targets but struggle with small ones. However, with the growing importance of aerial images in urban transportation and environmental monitoring, detecting small targets in such imagery has been a promising research hotspot. The challenge in small object detection lies in the limited pixel proportion and the complexity of feature extraction. Moreover, current mainstream detection algorithms tend to be overly complex, leading to structural redundancy for small objects. To cope with these challenges, this paper recommends the PCSG model based on yolov5, which optimizes both the detection head and backbone networks. (1) An enhanced detection header is introduced, featuring a new structure that enhances the feature pyramid network and the path aggregation network. This enhancement bolsters the model’s shallow feature reuse capability and introduces a dedicated detection layer for smaller objects. Additionally, redundant structures in the network are pruned, and the lightweight and versatile upsampling operator CARAFE is used to optimize the upsampling algorithm. (2) The paper proposes the module named SPD-Conv to replace the strided convolution operation and pooling structures in yolov5, thereby enhancing the backbone’s feature extraction capability. Furthermore, Ghost convolution is utilized to optimize the parameter count, ensuring that the backbone meets the real-time needs of aerial image detection. The experimental results from the RSOD dataset show that the PCSG model exhibits superior detection performance. The value of mAP increases from 97.1% to 97.8%, while the number of model parameters decreases by 22.3%, from 1,761,871 to 1,368,823. These findings unequivocally highlight the effectiveness of this approach.
通用目标检测算法在检测大中型目标时表现出色,但在检测小型目标时却举步维艰。然而,随着航空图像在城市交通和环境监测中的重要性日益凸显,在此类图像中检测小型目标已成为一个前景广阔的研究热点。小目标检测的难点在于像素比例有限和特征提取的复杂性。此外,目前主流的检测算法往往过于复杂,导致小目标的结构冗余。为了应对这些挑战,本文推荐基于 yolov5 的 PCSG 模型,该模型优化了检测头和主干网络。(1) 引入了增强型检测头,其新结构增强了特征金字塔网络和路径聚合网络。这一改进增强了模型的浅层特征重用能力,并为较小的对象引入了专用检测层。此外,还对网络中的冗余结构进行了修剪,并使用轻量级和通用的上采样算子 CARAFE 来优化上采样算法。(2) 本文提出了名为 SPD-Conv 的模块,以取代 yolov5 中的步进卷积运算和池化结构,从而增强骨干网的特征提取能力。此外,还利用幽灵卷积来优化参数数量,确保骨干网满足航空图像检测的实时需求。RSOD 数据集的实验结果表明,PCSG 模型表现出卓越的检测性能。mAP 值从 97.1% 增加到 97.8%,而模型参数数则减少了 22.3%,从 1,761,871 减少到 1,368,823。这些发现清楚地表明了这种方法的有效性。
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引用次数: 0
ARCnet: A Multi-Feature-Based Auto Radio Check Model ARCnet:基于多种特征的自动无线电检查模型
IF 2.6 3区 工程技术 Q2 Engineering Pub Date : 2024-05-14 DOI: 10.3390/aerospace11050391
Weijun Pan, Yidi Wang, Yumei Zhang, Boyuan Han
Radio checks serve as the foundation for ground-to-air communication. To integrate machine learning for automated and reliable radio checks, this study introduces an Auto Radio Check network (ARCnet), a novel algorithm for non-intrusive speech quality assessment in civil aviation, addressing the crucial need for dependable ground-to-air communication. By employing a multi-scale feature fusion approach, including the consideration of audio’s frequency domain, comprehensibility, and temporal information within the radio check scoring network, ARCnet integrates manually designed features with self-supervised features and utilizes a transformer network to enhance speech segment analysis. Utilizing the NISQA open-source dataset and the proprietary RadioCheckSpeech dataset, ARCnet demonstrates superior performance in predicting speech quality, showing a 12% improvement in both the Pearson correlation coefficient and root mean square error (RMSE) compared to existing models. This research not only highlights the significance of applying multi-scale attributes and deep neural network parameters in speech quality assessment but also emphasizes the crucial role of the temporal network in capturing the nuances of voice data. Through a comprehensive comparison of the ARCnet approach to traditional methods, this study underscores its innovative contribution to enhancing communication efficiency and safety in civil aviation.
无线电检查是地空通信的基础。为了整合机器学习以实现自动、可靠的无线电检查,本研究引入了自动无线电检查网络(ARCnet),这是一种用于民航非侵入式语音质量评估的新型算法,可满足可靠的地空通信的关键需求。通过采用多尺度特征融合方法,包括在无线电检查评分网络中考虑音频的频域、可理解性和时间信息,ARCnet 将人工设计的特征与自监督特征相结合,并利用变压器网络来增强语音片段分析。利用 NISQA 开源数据集和专有 RadioCheckSpeech 数据集,ARCnet 在预测语音质量方面表现出卓越的性能,与现有模型相比,其皮尔逊相关系数和均方根误差 (RMSE) 均提高了 12%。这项研究不仅强调了在语音质量评估中应用多尺度属性和深度神经网络参数的重要性,还强调了时态网络在捕捉语音数据细微差别方面的关键作用。通过将 ARCnet 方法与传统方法进行综合比较,本研究强调了其在提高民航通信效率和安全性方面的创新贡献。
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引用次数: 0
An Anomaly Detection Method for UAV Based on Wavelet Decomposition and Stacked Denoising Autoencoder 基于小波分解和堆叠去噪自动编码器的无人飞行器异常检测方法
IF 2.6 3区 工程技术 Q2 Engineering Pub Date : 2024-05-14 DOI: 10.3390/aerospace11050393
Shenghan Zhou, Zhao He, Xu Chen, Wenbing Chang
The paper proposes an anomaly detection method for UAVs based on wavelet decomposition and stacked denoising autoencoder. This method takes the negative impact of noisy data and the feature extraction capabilities of deep learning models into account. It aims to improve the accuracy of the proposed anomaly detection method with wavelet decomposition and stacked denoising autoencoder methods. Anomaly detection based on UAV flight data is an important method of UAV condition monitoring and potential abnormal state mining, which is an important means to reduce the risk of UAV flight accidents. However, the diversity of UAV mission scenarios leads to a complex and harsh environment, so the acquired data are affected by noise, which brings challenges to accurate anomaly detection based on UAV data. Firstly, we use wavelet decomposition to denoise the original data; then, we used the stacked denoising autoencoder to achieve feature extraction. Finally, the softmax classifier is used to realize the anomaly detection of UAV. The experimental results demonstrate that the proposed method still has good performance in the case of noisy data. Specifically, the Accuracy reaches 97.53%, the Precision is 97.50%, the Recall is 91.81%, and the F1-score is 94.57%. Furthermore, the proposed method outperforms the four comparison models with more outstanding performance. Therefore, it has significant potential in reducing UAV flight accidents and enhancing operational safety.
本文提出了一种基于小波分解和堆叠去噪自编码器的无人机异常检测方法。该方法考虑了噪声数据的负面影响和深度学习模型的特征提取能力。它旨在利用小波分解和堆叠去噪自编码器方法提高拟议异常检测方法的准确性。基于无人机飞行数据的异常检测是无人机状态监测和潜在异常状态挖掘的重要方法,是降低无人机飞行事故风险的重要手段。然而,无人机任务场景的多样性导致其所处环境复杂恶劣,获取的数据会受到噪声的影响,这给基于无人机数据的精确异常检测带来了挑战。首先,我们利用小波分解对原始数据进行去噪;然后,利用堆叠去噪自编码器实现特征提取。最后,使用 softmax 分类器实现无人机异常检测。实验结果表明,所提出的方法在噪声数据情况下仍然具有良好的性能。具体来说,准确率达到了 97.53%,精确率为 97.50%,召回率为 91.81%,F1 分数为 94.57%。此外,所提出的方法还优于四种对比模型,表现更为突出。因此,它在减少无人机飞行事故和提高操作安全性方面具有巨大潜力。
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引用次数: 0
Speech Recognition for Air Traffic Control Utilizing a Multi-Head State-Space Model and Transfer Learning 利用多头状态空间模型和迁移学习进行空中交通管制语音识别
IF 2.6 3区 工程技术 Q2 Engineering Pub Date : 2024-05-14 DOI: 10.3390/aerospace11050390
Haijun Liang, Hanwen Chang, Jianguo Kong
In the present study, a novel end-to-end automatic speech recognition (ASR) framework, namely, ResNeXt-Mssm-CTC, has been developed for air traffic control (ATC) systems. This framework is built upon the Multi-Head State-Space Model (Mssm) and incorporates transfer learning techniques. Residual Networks with Cardinality (ResNeXt) employ multi-layered convolutions with residual connections to augment the extraction of intricate feature representations from speech signals. The Mssm is endowed with specialized gating mechanisms, which incorporate parallel heads that acquire knowledge of both local and global temporal dynamics in sequence data. Connectionist temporal classification (CTC) is utilized in the context of sequence labeling, eliminating the requirement for forced alignment and accommodating labels of varying lengths. Moreover, the utilization of transfer learning has been shown to improve performance on the target task by leveraging knowledge acquired from a source task. The experimental results indicate that the model proposed in this study exhibits superior performance compared to other baseline models. Specifically, when pretrained on the Aishell corpus, the model achieves a minimum character error rate (CER) of 7.2% and 8.3%. Furthermore, when applied to the ATC corpus, the CER is reduced to 5.5% and 6.7%.
本研究为空中交通管制(ATC)系统开发了一种新型端到端自动语音识别(ASR)框架,即 ResNeXt-Mssm-CTC。该框架以多头状态空间模型(Mssm)为基础,并结合了迁移学习技术。残差网络(ResNeXt)采用多层卷积与残差连接,以增强从语音信号中提取复杂特征表征的能力。Mssm 具有专门的门控机制,它结合了并行头,可获取序列数据中局部和全局时间动态的知识。在序列标注中使用了连接主义时序分类(CTC),从而消除了强制对齐的要求,并适应不同长度的标注。此外,迁移学习的使用已被证明可以利用从源任务中获得的知识来提高目标任务的性能。实验结果表明,与其他基线模型相比,本研究提出的模型表现出更优越的性能。具体来说,在 Aishell 语料库上进行预训练时,该模型的最小字符错误率 (CER) 为 7.2% 和 8.3%。此外,当应用于 ATC 语料库时,CER 降至 5.5% 和 6.7%。
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引用次数: 0
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Aerospace
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