# Intelligent Gangue Sorting System Based on Dual-Energy X-ray and Improved YOLOv5 Algorithm

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## Abstract

**:**

## 1. Introduction

## 2. Coal Gangue Separation System Based on the DX-YOLOv5 Recognition Model

#### 2.1. Principle of Dual-Energy X-ray Recognition

#### 2.2. Data Collection

## 3. Improved Gangue Recognition Model Based on YOLOv5

#### 3.1. YOLOv5 Model

#### 3.2. Improvement of YOLOv5 Algorithm

#### 3.2.1. Lightweighting of the Backbone Network

#### 3.2.2. Enhancement of Feature Fusion Capabilities

- Design of LPAN modules

- 2.
- Introduction of the CBAM block

#### 3.2.3. Optimization of the Detection Head

#### 3.2.4. Modification of the Loss Function

#### 3.3. Enhanced Overall Network Architecture

**Figure 8.**Diagram of the improved overall network architecture. (The * sign in the figure indicates the multiplication sign).

## 4. Experiments and Discussions

#### 4.1. Experimental Configuration Framework

#### 4.2. Performance Evaluation

#### 4.3. Ablation Experiment

#### 4.4. Analysis of the Results

#### 4.5. Comparison with Other SOTA Models

## 5. Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 3.**Experimental environment: (

**a**) 3-D model of dual-energy X-ray coal separation system; (

**b**) experimental equipment diagram.

**Figure 5.**Comparison of MBConvh and Fused-MBConv modules: (

**a**) MBConv module; (

**b**) fused-MBConv module.

**Figure 9.**YOLOv5-S and improved YOLOv5-S average precision and recall rate comparison charts: (

**a**) YOLOv5-S; (

**b**) improved YOLOv5-S.

**Figure 10.**YOLOv5-S and improved YOLOv5-S coal gangue detection effect comparison chart: (

**a**) YOLOv5-S; (

**b**) improved YOLOv5-S.

**Table 1.**Coal gangue intelligent sorting system performance parameters (t/h indicates tonnes per hour).

Parameters | Numerical Value |
---|---|

Belt width | 1400 mm |

Belt speed | 2 m/s |

Sorting grain size | 50–600 mm |

Sorting volume | 120 t/h |

Ratio of coal in gangue | <1% |

Gangue sorting rate | >90% |

Size | 5000 mm × 2600 mm × 2600 mm |

System power | 100 kW (50 kW)@ 380 V |

**Table 2.**Comparison of experimental results between this method and baseline ablation (data in parentheses are the relative rate of change of each parameter relative to the baseline).

EfficientNetV2 | LPAN | CBAM | L2 | EIOU_Loss | [email protected] (%) | [email protected]:.95 (%) | Params (M) | FLOPs (G) |
---|---|---|---|---|---|---|---|---|

73.4 | 37.9 | 7.26 | 16.92 | |||||

√ | 78.9 (+7.5%) | 42.2 (+11.3%) | 5.49 (−24.4%) | 13.83(−18.3%) | ||||

√ | 79.6 (+8.4%) | 43.1 (+13.7%) | 7.26 (0) | 16.93 (+0.06%) | ||||

√ | 80.8 (+10%) | 44.0 (+16%) | 6.28 (−13.5%) | 14.82 (−12.4%) | ||||

√ | 81.4 (+10.9%) | 44.9 (+18.5%) | 7.66 (+5.5%) | 25.41 (+50.2%) | ||||

√ | 76.2 (+3.8%) | 40.7 (+7.3%) | 7.26 (0) | 16.92 (0) | ||||

√ | √ | √ | √ | √ | 87.5(+19.2%) | 50.2(+32.4%) | 3.52 (−51.5%) | 14.43 (−14.7%) |

**Table 3.**Comparing the property of dissimilar excellent algorithms on self-constructed gangue dataset.

Model | Params (M) | FLOPs (G) | [email protected] (%) | [email protected]:.95 (%) | Latency/MS | Model Size (MB) |
---|---|---|---|---|---|---|

NanoDet-Plus | 1.17 | 3.72 | 62.18 | 25.38 | 21.30 | 2.24 |

YOLOv5-N | 1.85 | 4.55 | 66.51 | 29.93 | 22.80 | 3.83 |

YOLOv5-S | 7.26 | 16.92 | 73.40 | 37.90 | 27.40 | 14.20 |

YOLOv5-M | 21.56 | 51.82 | 84.82 | 46.79 | 31.60 | 43.20 |

Improved YOLOv5-S | 3.52 | 14.43 | 87.50 | 50.20 | 25.30 | 7.10 |

YOLOv7 | 37.62 | 106.47 | 84.53 | 46.95 | 48.20 | 76.58 |

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**MDPI and ACS Style**

Qin, Y.; Kou, Z.; Han, C.; Wang, Y.
Intelligent Gangue Sorting System Based on Dual-Energy X-ray and Improved YOLOv5 Algorithm. *Appl. Sci.* **2024**, *14*, 98.
https://doi.org/10.3390/app14010098

**AMA Style**

Qin Y, Kou Z, Han C, Wang Y.
Intelligent Gangue Sorting System Based on Dual-Energy X-ray and Improved YOLOv5 Algorithm. *Applied Sciences*. 2024; 14(1):98.
https://doi.org/10.3390/app14010098

**Chicago/Turabian Style**

Qin, Yuchen, Ziming Kou, Cong Han, and Yutong Wang.
2024. "Intelligent Gangue Sorting System Based on Dual-Energy X-ray and Improved YOLOv5 Algorithm" *Applied Sciences* 14, no. 1: 98.
https://doi.org/10.3390/app14010098