*3.2.2 Experimental results and discussion of experiment 2*

Firstly, the mean accuracy rates and response times for each stimulus type and emission-time interval in the second experiment were illustrated in **Figure 6**. It was confirmed that there were the significant differences in accuracy rates for two factors: stimulus type (*p* < 0.01), emission-time interval (*p* < 0.001), and their interaction (*p* < 0.01), as the result of a two-way ANOVA considering the within-subject factors. Furthermore, there were significant differences in the response times for stimulus type (*p* < 0.05) and emission-time interval (*p* < 0.05).

Comparing the identification performance between sound types, the accuracy rate of identification for sound sequence using voice with emission-time interval 0.5 s was less than other cases, but the one for the other conditions was almost 100% because the task was performed completely. The identification of the emitting patterns of voice became difficult when the emitting voice stimulus switched to another speaker in the middle of the phrase. The performance in these emitting conditions became lower than in the other conditions.

#### **Figure 6.**

*Mean accuracy rates and response times regarding two experimental factors. (From Miyoshi [6]). (a) Mean accuracy rates and response times regarding stimulus type. (b) Mean accuracy rates and response times regarding the delay of stimuli.*

Comparing the results for the sequences emitting along the right-angle pattern to the one emitting along the straight-pattern (**Figures 3** and **7**), the mean-accuracy rates were higher for the emitting pattern at the right angle than in the straight line. In the second experiment, the subjects stood nearby the loudspeaker 23 and identified the sound sequences emitting in front of them. This is because identification performance for the sequence emitting in front of subjects was better than the backward ones as evaluated in the first experiment.

Next, the results regarding the sequence patterns are described. The mean accuracy rates and the response times, classed according to the sequence pattern and the spatial proximity to the stimulus from subject standing position were illustrated in **Figure 7**. The 12 sound sequences were classed into two level in the spatial proximity, "near" and "far" that were indicated with yellow and green lines in **Figure 5** respectively.

#### **Figure 7.**

*Mean accuracy rates and response times regarding the spatial proximity to sequence. (From Miyoshi [6]).*

## *Evacuation Guidance Assistance System Using Emitting Sound DOI: http://dx.doi.org/10.5772/intechopen.105223*

A two-way ANOVA was used to estimate how the means of the accuracy rates and the response times changed according to the levels of two factors, the sequence patterns and spatial proximity of stimuli from subjects. It was not confirmed that there was neither significant difference in the main factors nor in their interactions. The accuracy rate was almost 100% in all the cases. These results mean that there was no difference in the accuracy rates and response times depending on the sequence pattern, and that the subjects could perceive the sequences of acoustic stimuli emitted in front of them and identify the sequence pattern almost completely in cases where the emission pattern is a straight or right-angle. Therefore, the subjects might be able to follow the acoustic sequence of the emitting stimulus to the emergency exit more quickly even if the evacuation path is more complicate route including straight and right-angle paths. In discussing the practicality of evacuation guidance systems, the results are preferable for realizing a guidance system that emits acoustic stimuli along a predetermined evacuation path.

However, we observed no difference between the sequence shapes, which could be because there was a consistent distance between the loudspeakers. During an actual emergency, the evacuation path may contain a series of short paths to the exit. Therefore, in future, we will verify the subjects' performance with a smaller distance between the loudspeakers.
