This series, including 2 pictures and a video file, was made for representing my <a href="//commons.wikimedia.org/wiki/User:Jason_M._C.,_Han" title="User:Jason M. C., Han">Jason M. C., Han</a> (<a href="//commons.wikimedia.org/wiki/User_talk:Jason_M._C.,_Han" title="User talk:Jason M. C., Han"><span class="signature-talk">talk</span></a>) 07:36, 9 January 2019 (UTC) winter-swimming in 2018-2019 winter for Wikiversity's portal-building usage. For educational purposes, people can freely use, too. I selected a sample on Christmas Eve (December 24th) from many others (unrecorded) and explored to use more visualizing technologies (Video) to store and express this procedure. Because of the limitation of physics (I can't make if myself) and technologies (only my father took a smart-phone), I pleased my mother to record it, besides. But, she forgot to record the first-half stage; and at one interval, her attention was attracted by a naughtily crying seagull (several seconds, Wikipedia introduction: <a class="external free" href="https://en.wikipedia.org/wiki/Gull">https://en.wikipedia.org/wiki/Gull</a>) and distracted for a while... then, searched out my head and got back. Therefore, she has only recorded only 1 minutes and 23 seconds video file. 
<p>But Jason, how could we know how long your 'Christmas-Eve Winter-Swimming' has lasted, though we knew you were an honest boy, but evidence, please? 
Dear friends, don't worry. We can make some calculations of the time through indications given by those photos and video:
(1) My preparing-posture photo was made by my father at 12.15.11 a.m., and just after 26 seconds, a formal &amp; beautiful swimming photo got out at 12.15.37 a.m..  If in a very severe calculation way that preparation time cannot be added into the formal swimming time, there was merely 6-10 seconds before I got into the real swimming situation (I did a fast preparation on the beach based on the fact - in getting to Xinghai Square's bay-outskirt I had been doing the preparation) like the later formal swimming photo which my father took. But, in the end of my mother's video, she didn't record around 6-10 seconds, in which I got out from the water and prepared to cloth myself. Then, two times can be balanced out, and we can use the time 12.15.11 a.m. as the beginning time. 
After we got one side of Winter-Swimming, we can come to the other side - its ending time. Oh, the Forms' Converter from MP4 to WebM has only recorded its transforming time - today. Then, refering to file's property-time and my father phone's machine-time, it should be at 12.27.04 a.m., which was the beginning time my mother was recording. 1.23 minutes was its length, which should be added to. And, forgetting its balanced time mentioned before, we can get to 12.28.27 a.m., as the calculated ending time. By subtraction, we can know my Winter-Swimming time on Christmas Eve was approximately 13 minutes and 16 seconds. 
(2) Then, Jason, Why did you title it as 'for New Year'? To be honest, On New Year's Day, I did it in another time. However, very sorry to say, I cannot give any power ful evidence at all... Therefore, I use this series to represent the information of that period. 
</p>
(3) Finally, honest boy, where did you take your Winter-Swimming? Oh, I did it in a regular place I has been swimming throughout seasons - Xinghai Square's 'Outdoor Bar-bathing' beach (Wikipedia introduction: <a class="external free" href="https://en.wikipedia.org/wiki/Xinghai_Square">https://en.wikipedia.org/wiki/Xinghai_Square</a>). Indeed, as I saw,  there were many other people winter-swimming there and regularly throughout seasons (not only me), which made this sport as a great local winter sport as other famous places around the world. Hopefully, you can join if you give your 'LIKE'.
<a href="//commons.wikimedia.org/wiki/User:Jason_M._C.,_Han" title="User:Jason M. C., Han">Jason M. C., Han</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>