# FF-YOLO: An Improved YOLO11-Based Fatigue Detection Algorithm for Air Traffic Controllers
## 3 Materials and Methods
### Dataset Construction
#### 3.1.2 Dataset Labeling  
This study labels the fatigue status of ATCOs based on the subjective and objective fusion method. For the subjective dimension of fatigue assessment, the NASA-TLX scale  
\begin{table}
\begin{tabular}{c c c} \hline
**Dimensions** & **Descriptions** & **Weights** \\ \hline \multirow{4}{*}{Physical Demand} & The level of physical effort needed, including activities like pushing, pulling, turning, and controlling. Was the task physically easy or hard, slow or fast, relaxed or strenuous? & 0.07 \\ \hline \multirow{2}{*}{Temporal Demand} & The sense of time pressure due to the task’s pace. Did you feel the task was leisurely or rushed, slow or fast-paced? & 0.07 \\ \hline \multirow{2}{*}{Performance} & Your perceived success in achieving the task objectives. How well did you think you performed in meeting the goals of the task? & 0.07 \\ \hline \multirow{4}{*}{Effort} & The amount of mental and physical effort you had to exert to achieve your performance level. How hard did you have to work to accomplish the task? & 0.07 \\ \hline \multirow{4}{*}{Frustration Level} & The amount of mental and physical effort you had to exert to achieve your performance level. How hard did you have to work to accomplish the task? & 0.33 \\ \hline \multirow{4}{*}{Frustration Level} & The degree of stress, irritation, and annoyance you felt during the task. Did you feel secure, satisfied, content, relaxed, or did you feel insecure, discouraged, irritated, stressed, and annoyed? & \\ \cline{1-1}  & Pairwise comparison: The six dimensions were combined in pairs, resulting in 15 combinations, such as comparing Mental Demand with Physical Demand or Mental Demand with Temporal Demand. & 0.07 \\ \cline{1-1}  & Selection of the more important dimension: For each pair, participants were asked to select which dimension had a greater impact on workload. For example, in the comparison between Mental Demand and Physical Demand, if the participant deemed Mental Demand to be more important, a count of 1 was added to the tally for Mental Demand. & 0.07 \\ \cline{1-1}  & Weight calculation: The number of times each dimension was selected served as its weight. The range of weights was from 0 to 5, as each dimension could be selected a maximum of 5 times. & 0.07 \\ \cline{1-1}  & Each dimension is divided into 10 levels, from easy to difficult, corresponding to the scores of the dimension from small to large. After obtaining the scores of all dimensions by the ATCOs, the score of each dimension is multiplied by its corresponding weight, and then the weighted scores of all six dimensions are added together to obtain the comprehensive evaluation score. The evaluation score calculation formula is as shown in Formula 1, where Evaluation represents the comprehensive evaluation score, and Score and Weight represent the scores of each item and the corresponding weights. \\ \cline{1-1}  & Evaluation = \(\sum_{i=1}^{6}\left(Score_{i}\times Weight_{i}\right)\) & (1) \\ \cline{1-1}  & For instance, the NASA-TLX evaluation case of the controller shown in Figure 3 scored 8, 3, 8, 4, 7, and 5 for the six dimensions, which were multiplied by the corresponding dimension weights in Table 2 to obtain a NASA-TLX evaluation score of 6.83. \\ \cline{1-1}  & Dataset Labeling & \\ \cline{1-1}  & This study labels the fatigue status of ATCOs based on the subjective and objective fusion method. For the subjective dimension of fatigue assessment, the NASA-TLX scale & 0.07 \\ \cline{1-1}  & The fatigue status of ATCOs based on the subjective and objective fusion method. For the subjective dimension of fatigue assessment, the NASA-TLX scale & 0.  
was employed, with weights for each dimension determined based on the characteristics of the control tasks, thereby quantifying the workload perception of ATCOs. According to related research on the cumulative frequency distribution of NASA-TLX scores for ATC tasks [26], evaluation scores from 7 to 10 are considered indicative of subjective fatigue in ATCOs.