## 4 Discussion
Since the application of the text is culture dependent, the use of variable message signs (VMS) technology can be used to display the text in different languages and can be placed at key decision points to facilitate better comprehension of drivers and nondrivers [46]. Within countries, sign improvements have focused on ensuring both the consistency of design and the standardizing of sign design across countries and cultures [47]. To resolve the issue of comprehension between drivers and nondrivers, [PERSON] [16] suggested the conduct of training to enhance the users' comprehension, especially for some symbolic signs that were difficult to comprehend. In the study of [PERSON] et al. [48], they studied the differences in comprehension and matching time on airport safety signs before and after training. The participants' comprehension and matching time for symbolic signs were enhanced after recognition and recall training. [PERSON] and [PERSON] [3] also found that training significantly enhanced sign comprehension from an average comprehension score of 52% before training to 94% immediately after training. In addition, [PERSON] et al. [49] studied comprehension differences of pharmaceutical and industrial-safety signs before and after training and found that the comprehension of difficult signs before the training was 54% for the former and 34% for the latter, but this improved to 87% and 63%, respectively, six months after the training. Although there are cases when the comprehension level drops after a month [49,50], it is still better compared to the comprehension level before training. [PERSON] and [PERSON] [51] explained that combining enforcement with education and training will have long-term effects on driver attitudes towards comprehension. Thus, educating all road users through continuous education or the retraining of drivers is a must. [PERSON] and [PERSON] [52] also recommended that a test of traffic sign meaning should be considered as part of a relicensing process for drivers, to verify that they are familiar with new signs, and to refresh their memory on sign meanings in general. Thus, adapting retraining in license application and renewal in the country may help road users improve or sustain their knowledge regarding traffic signs. Therefore, the matching test developed in this study could be adopted as a mandatory retraining requirement for the renewal of drivers licenses by the Land Transportation Office (LTO), the government agency in the Philippines responsible for the issuance of licenses and permits. Upon the application or renewal of a license, the driver could be asked to take the matching test as a mandatory retraining requirement, and only after obtaining a 67% comprehension score could their drivers license be released. Furthermore, the LTO could use the results of the matching test to regularly analyze the comprehension level of Filipino drivers to find out which signs are difficult to comprehend. Our matching-based comprehension test can also be applied and extended to evaluate existing traffic signs worldwide. Aside from improving traffic sign comprehension, other strategies to improve road safety include the prediction of short-term traffic flow. [PERSON] et. al. [53] evaluated the various smoothing models for cleaning anomalies in traffic flow data, which were further processed to predict short-term traffic flow evolution using artificial neural networks. The findings of the study provided efficient and accurate denoising approaches for short-term