# Research on Safety Prediction of Sector Traffic Operation Based on a Long Short Term Memory Model

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## Abstract

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## 1. Introduction

^{−9}collisions per flight hour [13]. A combination of LSTM model and DNN model is used to predict the en-route flight safety, in which probabilistic separation distance is used as a quantitative safety metric [16]. However, the uncertainty in air traffic (such as weather uncertainty) increases the difficulty in recognizing conflicts issues, and the nonlinear characteristic of flight conflict has been verified, which means that the changes in flight conflict are complex and hard to understand and predict [17].

## 2. Air Traffic Parameters in Sectors

#### 2.1. Definition of Traffic Parameters

#### 2.2. Definition of Safety Parameters

## 3. Time Series Forecasting Model

#### 3.1. Time Series Forecasting

#### 3.2. LSTM Model

#### 3.3. Performance Indicators

## 4. Case Study

#### 4.1. Time Series Forecasting without Traffic Parameters

#### 4.2. Time Series Forecasting with Traffic Parameters

#### 4.3. Correlation Analysis

#### 4.3.1. Coefficient Calculation

#### 4.3.2. Coefficient Calculation under Time Delay

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 13.**Traffic parameter time series. (

**a**) The statistical distribution of paprameters on September 1st (

**b**) The statistical distribution of parameters between 400 min and 650 min on Spetember 1st.

CallSign | Longitude | Latitude | Height | Speed | ... | Time |
---|---|---|---|---|---|---|

SKW4310 | −104.685 | 38.826 | 2324.10 | 333.35 | ... | 22:25:09 |

SKW4310 | −104.516 | 38.862 | 3581.39 | 629.67 | ... | 22:27:39 |

SKW4310 | −104.474 | 38.592 | 5577.83 | 685.23 | ... | 22:30:21 |

SKW4310 | −104.500 | 38.323 | 7132.31 | 740.79 | ... | 22:32:57 |

Batch Size | Neurons = 10 | Neurons = 20 | Neurons = 30 | ||||||
---|---|---|---|---|---|---|---|---|---|

Learning Rate | MAE | RMSE | Learning Rate | MAE | RMSE | Learning Rate | MAE | RMSE | |

120 | 0.1 | 0.6698 | 1.4344 | 0.1 | 0.7808 | 1.6602 | 0.1 | 1.1558 | 2.2456 |

0.01 | 0.6122 | 1.4699 | 0.01 | 0.5919 | 1.3938 | 0.01 | 0.5756 | 1.3461 | |

0.001 | 0.5561 | 1.4566 | 0.001 | 0.6583 | 1.5871 | 0.001 | 0.5559 | 1.4510 | |

180 | 0.1 | 0.7416 | 1.6152 | 0.1 | 1.2039 | 2.3464 | 0.1 | 1.8482 | 3.3518 |

0.01 | 0.5524 | 1.3160 | 0.01 | 0.5756 | 1.3461 | 0.01 | 0.5756 | 1.3461 | |

0.001 | 0.4520 | 1.0235 | 0.001 | 0.6903 | 1.7057 | 0.001 | 0.4783 | 1.0996 | |

240 | 0.1 | 0.6405 | 1.5370 | 0.1 | 1.7343 | 3.1770 | 0.1 | 1.8482 | 3.3518 |

0.01 | 0.6475 | 1.5399 | 0.01 | 0.5929 | 1.3945 | 0.01 | 0.5756 | 1.3461 | |

0.001 | 0.4380 | 0.9157 | 0.001 | 0.6572 | 1.5843 | 0.001 | 0.4147 | 0.9183 | |

300 | 0.1 | 0.6393 | 1.5341 | 0.1 | 1.8482 | 3.3518 | 0.1 | 1.8482 | 3.3518 |

0.01 | 0.6666 | 1.5906 | 0.01 | 0.6655 | 1.5899 | 0.01 | 0.6655 | 1.5899 | |

0.001 | 0.4130 | 0.8311 | 0.001 | 0.5005 | 1.2870 | 0.001 | 0.3901 | 0.8037 | |

360 | 0.1 | 0.6851 | 1.6164 | 0.1 | 1.8482 | 3.3518 | 0.1 | 1.8482 | 3.3518 |

0.01 | 0.6460 | 1.5276 | 0.01 | 0.6564 | 1.5527 | 0.01 | 0.6655 | 1.5899 | |

0.001 | 0.4492 | 0.8721 | 0.001 | 0.4521 | 1.0801 | 0.001 | 0.4102 | 0.8308 |

Model | Case 1 | Case 2 | Case 3 | |||
---|---|---|---|---|---|---|

MAE | RMSE | MAE | RMSE | MAE | RMSE | |

SVR | 1.7500 | 2.5814 | 0.7050 | 1.7709 | 0.0500 | 0.2328 |

LSTM | 1.9062 | 3.0783 | 0.3901 | 0.8037 | 0.0493 | 0.2252 |

RR | 1.7877 | 3.0092 | 0.6259 | 1.5346 | 0.0500 | 0.2328 |

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**MDPI and ACS Style**

Lyu, W.; Zhang, H.; Wan, J.; Yang, L.
Research on Safety Prediction of Sector Traffic Operation Based on a Long Short Term Memory Model. *Appl. Sci.* **2021**, *11*, 5141.
https://doi.org/10.3390/app11115141

**AMA Style**

Lyu W, Zhang H, Wan J, Yang L.
Research on Safety Prediction of Sector Traffic Operation Based on a Long Short Term Memory Model. *Applied Sciences*. 2021; 11(11):5141.
https://doi.org/10.3390/app11115141

**Chicago/Turabian Style**

Lyu, Wenying, Honghai Zhang, Junqiang Wan, and Lei Yang.
2021. "Research on Safety Prediction of Sector Traffic Operation Based on a Long Short Term Memory Model" *Applied Sciences* 11, no. 11: 5141.
https://doi.org/10.3390/app11115141