1. What is the purposes of this slide? This slide is used to confirm the effects of applying the moving average method and showing the difference of choosing the intervals of moving average. It shows for providing the confidence of myself due to I use the self-developed program. For the tidal data sampled at one hour interval, two major intervals of 24 hrs (red line) and 72 hrs (green line) are applied and shown. In addition, a 30 hrs intervals of re-moving average of the 24 hrs is also tried and shown (blue line). Basing on this result, I find that the re-moving average of specific short interval seems to present better than the one of directly applying long period to interpret the essential oscillation trend.

2. Why showing two diagrams for the same station at the same time? The red lines are the same, but the two 15 pts moving average lines are different. The upper diagram, why I show here, is mainly applied to verify the characteristics and relationship of the infragravity waves that possibly generated by the incidence of short wave trains (images described in the pdf file of infragravity waves what I had sent to you for reference a few days ago, or please refer to the succeeding slide). In this panel, the variations of green line (*not the results of 15 pts moving average) show the possible wave grouping or short waves trains which is filtered and obtained by subtracting the trend of 15 pts moving average (blue line in lower panel) from the original measurement series (black line in lower panel). The line plots shown in the lower diagram can be easily read by the related legend. In addition, interested one could find the effects of applying different intervals on moving average. Hereby, the trend of long waves is presented by applying the 30pts moving average. The reason please refer to the first slide.

3. The images presented on the right panel show the possible essential appearances of wave oscillations at near shore region. Basing on above image, This is the cause of why I generate the upper panel on previous and following slides. Referring to the previous slide, #2, it is noted that the long waves – infragravity waves are dominant, however, the appearances of grouping of short waves are not clear. Nevertheless, the ranges of long wave periods obtained from moving average at stations of ST5, w22, w08, and w10 could be analyzed further to clarify that the disasters what had occurred in HL Harbor were dominated by either the incident- reflecting effects or harbor resonance. Prof. Hwang, Lab. Measurement of infragravity waves on a near shore slope. Images of infragravity waves

4. Same question as marked in the previous slide. The same explanations as comments in the previous slide, #2. Referring to the upper panel, it is noted that the appearances of both the long waves – infragravity waves and short wave grouping are clear. Some of the characteristics of waves grouping and long waves shown on slide #2 are exhibited on the up right panel.

5. Same question as marked in the previous slide. The same explanations as comments in the previous slide. The amplitudes of both the long waves – infragravity waves and short wave are almost in the same order.

6. Same question as marked in the previous slide. The same explanations as comments in the previous slide. The amplitudes of both the long waves – infragravity waves and short wave are almost in the same order.

7. Warf # 8 Warf # 22 Warf # 10 Sta. 5 Can you just plot the 30 pts moving averaged and using the same Vertical scale? The above plot is modified as showing on the right panel by using 30pts moving average (based on the one of 15pts moving average) and using the same vertical scale.

8. Discussions and comments