Summer Challenge 2019

Gradient descent on map

This was the first time for many students to come across the gradient descent concept, but many were soon pulled in as they learned about its link to machine learning. This challenge was designed so that students could experience advanced content in three simple steps.

First, after grasping the principle using intuition, students traced a route down a mountain which was perpendicular to the contour lines on their map. Next, students learned how to express this route using a mathematical expression and calculation. And finally, students attempted to apply gradient descent to artificial intelligence. By running a simulation and allowing the computer to perform complex calculations, students were able to observe how the "learning error" and "test error" change, and were asked to discuss how they could minimize the latter.

A challenging 90 minutes indeed!

Observing planets being born

After a short excursion outdoors, it was time to jump into the world of space and planets with Challenge 5.

Even within our solar system, planets vary greatly. We have rocky planets like Earth, gassy planets like Jupiter, and massive icy planets like Neptune. Other stellar planetary systems are even more diverse.

Still, each of these unique planets seem to follow a common process before they are born, with dust playing a key role. This cosmic dust, often less than 1 µm in size, wraps around a star and forms a disk. This dust coalesces further to create a larger mass, which in turn creates a planet. When a newly formed planet is in orbit, it opens a gap in the disk. Therefore, if a gap is observed around a star, a newly born planet may very well be orbiting it.

HL Tauri has around it a dusty disk with three prominent gaps. Students were asked to calculate a theoretical value for the thickness of this disk so that these gaps could be seen not only from directly above, but also from a 45-degree angle. A challenge of truly infinite scale that combined observation and theoretical calculation.

Transportation system with emphasis on disaster prevention

Transportations systems have come a long way with human endeavors, but the need to secure energy for these systems and the issue of global warming caused by fossil fuel-generated carbon dioxide emissions have been on a head-on collision course for some time. Additionally, safety is of utmost importance, particularly for aging societies.

After listening to a short lecture, students groups were asked to design their dream transportation system. They were encouraged to set goals for new systems first. What should they focus on? Safety? Efficiency? Energy saving?

Some teams focused on freedom and envision individual vehicles, while others combined units to design highly efficient systems. When it was time to design plans on paper, the female students in many groups took on leadership roles.

Cladonema pacificum jellyfish reproduce in two ways

Being alive...what does it mean? Jellyfish can provides clues to answering this very big question. Cladonema pacificum jellyfish, for example, can reproduce using both asexual and sexual reproductive systems. After some knowledge sharing on these unique organisms, students moved on to discuss bacteria, hibernating mice, ancient lotus seeds, and other seemingly "lifeless" plants and animals, and debated standards and methods to determine whether these species were "dead or alive."

Many suggestions emerged — observation with a microscope, stimulation with electricity or chemicals, or simply waiting to see if species decayed. In this last challenge, students seemed to split into two camps — those who wanted to apply direct stimulus despite the risks involved, and those who preferred a more non-invasive approach.