## 2 Recommended Topology and Working Principles
### GUI Interface and Usage  
As depicted in Figure 4, upon opening the program, users are greeted with three interfaces. Upon accessing the 'horn sound generator' tab, users encounter the panel of the sound generation software discussed in the article. The 'EQ Unit' section features a conventional equalizer system, enabling users to adjust the magnitude levels of loaded sounds within specific frequency ranges. The 'AVAS Sound Flash' or Audio Flashing unit converts any audio file into a format compatible with the proposed devices, ensuring adaptability and suitability. As illustrated in Figure 4, upon opening the program, users are presented with three distinct interfaces. Upon accessing the horn sound generator tab, users encounter the panel of the sound generation software discussed in this study. The EQ Unit section features a standard equalizer system, allowing users to adjust the magnitude levels of loaded sounds within specific frequency ranges. Additionally, the Audio Blink Unit transforms any audio file into a system compatible with the proposed devices. Upon entering the horn sound generation unit, users are welcomed with an interface, as depicted in Figure 5. Sound is generated by inputting specific frequency values and harmonic numbers within this interface. Optionally, users can activate the limiter option, which operates on a percentage basis and can be assigned a value ranging from 0 to 100. When the Play Sound button is pressed, the adjusted sound is heard immediately, and its graphic is displayed on the screen, according to Figure 6. Pressing the Save Sound button opens a pop-up screen that allows saving the created sound in _.wav_ format. Figure 4: Sound design interface. Figure 5: Horn sound generator unit. Figure 6: A horn sound that has been created and displayed within the graphical interface of the unit. As depicted in Figure 7, upon pressing the dB Organize Menu button, a new interface opens, featuring scroll boxes that allow for adjustment of the dB settings. Users can modify the settings using the sliders and then apply the changes by pressing the Apply dB Settings button. Subsequently, when the interface is closed, pressing the Play Sound or Save Sound buttons will generate sound with the newly edited dB settings. The GUI interface is not utilized directly within the vehicle. Instead, its output--a sound file (digital horn sound)--is stored in the memory of the AVAS device and used directly on the vehicle. Traditional methods for creating digital horn sounds require signal information, sound processing expertise, and mathematical computations, which can be time-consuming and costly. In contrast, the GUI interface streamlines the sound design and editing process, allowing unique sound outputs to be generated in just seconds. This significantly reduces both time and cost, offering substantial efficiency benefits. Based on Figure 8, upon accessing the EQ Apply Unit, users encounter the displayed interface. After clicking the browse button within this interface and selecting an audio file, the relevant frequency values are entered in the Equalizer Setting sections within the Band sections. A value (either negative or positive) is then inputted in the Gain section to adjust the desired quantity. Pressing the Apply Equalizer button activates the Processed Audio feature. By clicking this button, users can listen to the audio with the equalizer applied. Additionally, pressing the Original Audio button enables users to listen to the original version of the selected audio. Lastly, clicking the Save button opens a pop-up screen, allowing users to save the synchronized audio in _.wav_ format. Figure 8: EQ Apply Unit main interface. Figure 7: dB organization menu. The interface of the AVAS Sound Flash Unit is displayed in Figure 9. As previously mentioned, this interface is encrypted and accessible only to employees. Through this interface, standards can be loaded, and amplitude settings can be adjusted based on the speed levels of the selected sounds.