Delong Han

Dr. Delong Han


Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 May 2023 in Engineering Applications of Artificial Intelligence
Verified
Journal Article
Closed access
ZZZekai Zhang
Zekai Zhang
MZMingle Zhou
Mingle Zhou
HWHonglin Wan
Honglin Wan
MLMin Li
Min Li
GLGang Li
Gang Li
DHDelong Han
Delong Han

29 February 2024 in Complex & Intelligent Systems
Verified
Journal Article
Open access
PDF file
RSRui Shao
Rui Shao
MZMingle Zhou
Mingle Zhou
MLMin Li
Min Li
DHDelong Han
Delong Han
GLGang Li
Gang Li
The detection of tiny defects in industrial products is important for improving the quality of industrial products and maintaining production safety. Currently, image-based defect detection methods are ineffective in detecting tiny and variously shaped defects. Therefore, this paper proposes a tiny defect detection network (TD-Net) for industrial products to improve the effectiveness of tiny defect detection. TD-Net improves the overall defect detection effect, especially the detection effect of tiny defects, by solving the problems of downsampling of tiny defects, pre-filtering of conflicting deep and shallow semantic information, and cascading fusion of multi-scale information. Specifically, this paper proposes the Defect Downsampling (DD) module to realize the defect information supplementation during the backbone downsampling process and improve the problem that the stepwise convolution easily misses the detection of tiny defects. Meanwhile, the Semantic Information Interaction Module (SIIM) is proposed, which fuses deep and shallow semantic features, and is designed to interact the fused features with shallow features to optimize the detection of tiny defects. Finally, the Scale Information Fusion Module (SIFM) is proposed to improve the Path Aggregation Network (PANet) for cascading fusion and information focus on different scale information, which enables further improvement of defect detection performance of TD-Net. Extensive experimental results on the NEU–DET data set (76.8 $$\%$$ % mAP), the Peking University PCB defect data set (96.2 $$\%$$ % mAP) and the GC10-DET data set (71.5 $$\%$$ % mAP) show that the proposed TD-Net achieves competitive results compared with SOTA methods with the equivalent parameter quantity.

16 December 2022 in Electronics
Verified
Journal Article
Open access
PDF file
GLGang Li
Gang Li
SZshilong zhao
shilong zhao
MZMingle Zhou
Mingle Zhou
MLMin Li
Min Li
RSRui Shao
Rui Shao
DHDelong Han
Delong Han
Aiming at the problems of low efficiency, high false detection rate, and poor real-time performance of current industrial defect detection methods, this paper proposes an industrial defect detection method based on an expanded perceptual field and feature fusion for practical industrial applications. First, to improve the real-time performance of the network, the original network structure is enhanced by using depth-separable convolution to reduce the computation while ensuring the detection accuracy, and the critical information extraction from the feature map is enhanced by using MECA (More Efficient Channel Attention) attention to the detection network. To reduce the loss of small target detail information caused by the pooling operation, the ASPF (Atrous Spatial Pyramid Fast) module is constructed using dilate convolution with different void rates to extract more contextual information. Secondly, a new feature fusion method is proposed to fuse more detailed information by introducing a shallower feature map and using a dense multiscale weighting method to improve detection accuracy. Finally, in the model optimization process, the K-means++ algorithm is used to reconstruct the prediction frame to speed up the model’s convergence and verify the effectiveness of the combination of the Mish activation function and the SIoU loss function. The NEU-DET steel dataset and PCB dataset is used to test the effectiveness of the proposed model, and compared to the original YOLOv5s, our method in terms of mAP metrics by 6.5% and 1.4%, and in F1 by 5.74% and 1.33%, enabling fast detection of industrial surface defects to meet the needs of real industry.

9 February 2023 in Applied Sciences
Verified
Journal Article
Open access
PDF file
MLMin Li
Min Li
MSMengjie Sun
Mengjie Sun
GLGang Li
Gang Li
DHDelong Han
Delong Han
MZMingle Zhou
Mingle Zhou
Effective log anomaly detection can help operators locate and solve problems quickly, ensure the rapid recovery of the system, and reduce economic losses. However, recent log anomaly detection studies have shown some drawbacks, such as concept drift, noise problems, and fuzzy feature relation extraction, which cause data instability and abnormal misjudgment, leading to significant performance degradation. This paper proposes a multi-feature deep fusion of an unstable log anomaly detection model (MDFULog) for the above problems. The MDFULog model uses a novel log resolution method to eliminate the dynamic interference caused by noise. This paper proposes a feature enhancement mechanism that fully uses the correlation between semantic information, time information, and sequence features to detect various types of log exceptions. The introduced semantic feature extraction model based on Bert preserves the semantics of log messages and maps them to log vectors, effectively eliminating worker randomness and noise injection caused by log template updates. An Informer anomaly detection classification model is proposed to extract practical information from a global perspective and predict outliers quickly and accurately. Experiments were conducted on HDFS, OpenStack, and unstable datasets, showing that the anomaly detection method in this paper performs significantly better than available algorithms.

21 January 2023 in Applied Sciences
Verified
Journal Article
Open access
PDF file
CZCheng Zhang
Cheng Zhang
GLGang Li
Gang Li
ZZZekai Zhang
Zekai Zhang
RSRui Shao
Rui Shao
MLMin Li
Min Li
MZMingle Zhou
Mingle Zhou
The pothole is a common road defect that seriously affects traffic efficiency and personal safety. Road evaluation and maintenance and automatic driving take pothole detection as their main research part. In the above scenarios, accuracy and real-time pothole detection are the most important. However, the current pothole detection methods can not meet the accuracy and real-time requirements of pothole detection due to their multiple parameters and volume. To solve these problems, we first propose a lightweight one-stage object detection network, the AAL-Net. In the network, we design an LF (lightweight feature extraction) module and use the NAM (Normalization-based Attention Module) attention module to ensure the accuracy and real time of the pothole detection process. Secondly, we make our own pothole dataset for pothole detection. Finally, in order to simulate the real road scene, we design a data augmentation method to further improve the detection accuracy and robustness of the AAL-Net. The metrics F1 and GFLOPs show that our method is better than other deep learning models in the self-made dataset and the pothole600 dataset and can well meet the accuracy and real-time requirements of pothole detection.

13 May 2024 in IEEE Transactions on Intelligent Vehicles
Verified
Journal Article
Closed access
GLGang Li
Gang Li
CZCheng Zhang
Cheng Zhang
MLMin Li
Min Li
DHDelong Han
Delong Han
MZMingle Zhou
Mingle Zhou
Road surface defect detection can effectively reduce maintenance costs, which is a critical component in road structural health monitoring. However, existing methods often face challenges in the heavy computational parameters and high-accuracy detection, limiting their practical applicability in resource-constrained industrial settings. To alleviate this gap, we propose a Lightweight and High-accuracy Network (LHA-Net) for road surface defect detection, consisting of three sub-networks for feature extraction, feature fusion, and detection head. First, the proposed Direction-guided Global Feature-Aware Module (DGFM) and the proposed Heterokernel Local Feature-Aware Module (HLFM) are used in the feature extraction sub-net to extract global and local features while minimizing network parameters. Second, we propose an Asymptotically Weighted Aggregation Mechanism (AWAM) in the feature fusion sub-net, which efficiently merges detailed and semantic features through asymptotic multi-scale fusion and weighted fusion at multiple stages. Third, we propose a Lightweight Decoupling Head (LDH) in the detection head sub-net to extract target location and category information by emphasizing defect details in horizontal and vertical dimensions. Finally, to improve the generalizability, we propose the RDD-CC dataset extension of RDD2022 using road images collected by automobiles in China. Compared with the well-established lightweight YOLOv8n, LHA -Net achieves comparable or superior mAP@.5 scores with gains of +0.8%, +0.5%, and +0.3% on RDD-CC, RDD-SCM, and RDD-SCD datasets, respectively. Remarkably, LHA-Net does so with only 2.5M parameters (reduced by 16%) and 5.6 GFLOPs (reduced the computational load by 30%). The code and datasets are available at https://github.com/ZCZST01/LHA-Net .