## 3 Results
### Model Verification
Due to its nature, the model is not a musculoskeletal model, making traditional verification processes unsuitable compared to those used for other models. Instead, the model is theoretically verified using empirical data from similar research to assess the validity of the obtained data. [PERSON] conducted a study measuring shoulder and elbow moments during daily tasks. One straightforward and easily comparable task, lifting an object to shoulder height, was selected for model verification. In [PERSON]'s study, the task was repeated 10 times. The highest shoulder moment was recorded when raising the hand to shoulder height with a 5 N object, yielding a maximum moment of 14.3 \(\pm\) 1.4 Nm. Similarly, the maximum elbow moment was 5.8 \(\pm\) 0.5 Nm. These scenarios served as the first verification scenarios for hand movements. Another scenario involved extending the arm to shoulder level while holding a 2 kg object, resulting in a moment of 22.5 \(\pm\) 1.4 Nm. Given the variation in anthropometric data among subjects, identical results were not expected. However, if the values in the computational model fall within \(\pm\)10%, it indicates that the output data are reasonably accurate and valid. [PERSON]'s study involved 10 males aged 34.3 \(\pm\) 11 years [32]. The model verification calculations are also performed with a male subject, repeating the motion of extending the arm to shoulder level seven times under the same load as in the reference study. Verification of comparison data is presented in Figure 10D-F graphs. The verification of the neck moment calculation model was conducted using a similar method. After analyzing the studies, research by [PERSON] [33], conducted with 32 participants aged 21.5 \(\pm\) 1.63, was discovered. This research focused on determining the kinematic and dynamic impacts on the neck across various scenarios related to posture while using a mobile phone. This study identified neck flexion angles of 15\({}^{\circ}\), 30\({}^{\circ}\), and 45\({}^{\circ}\), measured the moments, and provided averages with standard deviation. To validate the model's neck bending moment settings, calculations were performed for 10 subjects under these conditions. Simulated motion amplitudes were input into the model with the body in a vertical position, and only the neck position was modified. The comparison results are presented in Figure 10A-C graphs. Figure 10A-C plot displays time-normalized values, highlighting the segment representing the shoulders in the extended arm position. The curve fluctuations represent limb variability across different measurements and arm instability within the same measurement period, depicting a fluctuation period of approximately 2-3 s due to data normalization. In the initial verification, comparing shoulder moments with a 5 N weight, the average difference between the comparative and model values for the shoulders is 4.28%. The average difference between the comparative and model values for the elbows is 2.81%. In the second verification, the average shoulder difference is 7.17%, with an average shoulder error for both scenarios of 5.73%. It is considered that the main influence on the differences between measurements comes from varying anthropometric data of the subjects. In the neck moment calculation verification, it was observed that in all scenarios, the model consistently estimates a lower neck moment compared to the provided average. The differences between the averages of both studies are not linear. In scenario A, with a 15\({}^{\circ}\) head tilt, the numerical model yields an average value of 3.51 \(\pm\) 0.59 Nm, while the comparative model provides an average of 3.79 \(\pm\) 0.70 Nm, resulting in a 7.28% difference. In scenario B, with a 30\({}^{\circ}\) head flexion, the model's average is 4.75 \(\pm\) 0.81 Nm versus the comparative model's 5.37 \(\pm\) 0.65 Nm, indicating an 11.61% difference.