GTC DC 2019

Nov 5. Day 1

Keynote: CLARA, GAN (for Bob Ross like paintings), reinforcement learning (backflip), DeepStream, self-driving car, multiple DNN in production, 5G.

GAN demo

Thispersondoesnotexist.com

Healthcare AI

Pathology AI

Multimodal fusion, Graphical CN, GAN

Mahmoodlab.org

Voice classification demo.

Multiple video feeds.

Simulator running on NANO.

Nov 6, Day 2

Autoencoder and anomaly detection from reconstruction error

HigherEd panel

  • Relationship with industry
  • Convergence of multiple industries and disciplines
  • Computing as pervasive tool

  • Digital literacy (foundational skills)
  • Younger kids (middle school)
    Computing Across Curriculum like Writing.
    Masters program for continuing education, industry certification
    Digital ethics

Super resolution with autoencoder

PyTorch (Captum)

Arduino Engineering Kit

Several physics students have been testing the Arduino Engineering Kit, since the beginning of the spring semester.  They have built the rover and the drawing bot, and are now in the programming stage.  We are working through some difficulties with the software setup and sharing some trouble-shooting steps here.  Our environment is Windows 7 and Matlab 2018b.

One of the first problems we encountered was that we were missing MKRMotorCarrier, which was solved by ensuring that all the following add-on’s were installed in Matlab:

  • MATLAB Support Package for Arduino Hardware
  • Simulink Support Package for Arduino Hardware
  • Arduino_Engineering_Kit_Hardware_Support_18b

Another issue was that we were missing some libraries (e.g., WiFi101), despite the fact that we had those libraries, according to the Arduino IDE (version 1.8.8) that we had installed separately.  However, it turns out that Matlab was looking at the Arduino IDE (version 1.8.1).  You can check the Arduino IDE by typing “winopen(arduinoio.IDERoot)” at the command window. Then, open the IDE, and make sure that the following are installed: MKRMotorCarrier (version 1.0.1) and WiFi101 (versions 0.14.3).

Once done, we were able to connect to the Arduino.

Reverse-Engineering a Hand-crank Flashlight

I picked up a $1 hand-crank flashlight at a Dollar Store. I thought it would be a good teaching material for an introductory physics course. In particular, it contains a magnet and a coiled wire for generating electricity.

This is what the internal components look like.  The handcrank turns the large gear.

The ring shaped magnet rotates by the hand-crank and a set of gears on top of a coiled wire.

Note that N and S poles alternate around the ring.

The magnet would sit on top of this spool of coil and rotate. You can see two ends of the wire sticking out. There are two cross-shaped metal posts. As the ring-shaped magnet rotates, these two metal posts will alternate between N and S poles, creating changing magnetic flux through the coil and generating emf, according to Faraday’s law.

Other interesting bits found inside were: a set of gears that makes the magnet rotate in one direction only.

Thermal Physics Teaching Resources

Here are some resources that can be incorporated into a thermal physics course.

Entropy explained, with sheep“: An interactive tutorial by Aatish Bhatia.  Highly recommended.

COBE and COBRA: “The experiment that confirmed – and almost beat – COBE” from Physics Today (2018).  I did not know about COBRA until I read this physics today article.  I found the PRL paper (1990) was easier to read and present to the students.  For example, COBRA paper shows the acceleration of the rocket launch.  The history of COBE vs COBRA is interesting, and it is nice to have an opportunity to acknowledge the importance of confirmation.

from Physics Today article on COBE and COBRA.

“Max the Demon vs Entropy of Doom”: It is a graphic novel with many physics jokes.  It even goes into some discussions about entropy and information, featuring many physicists such as Thompson, Carnot, Boltzmann, and Feynman. 

Computer assignments: (1) Given a formula like the blackbody radiation or speed distribution of ideal gas, make a plot at different temperatures.  Find the maximum (wavelength or speed).  (2) Calculate the first 50 terms of the Boltzmann factor (e.g., for rotational degree of freedom, which does not have analytical solution, unlike vibration).  Find the sum (as an estimate of the partition function) and plot a bar graph as a function of angular momentum quantum number, L.  Find out which state has the largest occupancy.

Teaching Thermal Physics in 2018

2018 was a fun year to teach thermal physics.  At Drew, this course is offered every other year, using a textbook by the late Dr. Ashley Carter.  The Chapter 18 in the textbook is about blackbody radiation, and students (and I) enjoy wrapping up the course with some reviews of Bose-Einstein statistics (i.e., counting the number of microstates for photons), optimization of entropy with Lagrange multiplier, calculation of degeneracy, etc.  

“Classical and Statistical Thermodynamics” by Ashley Carter, who was a member of the Drew Physics Department (as well as the Bell Laboratory).

Using some modern physics (e.g., E = hv = hc/lamda), students then are able to derive the formula for the blackbody radiation in the same form as appears in Planck’s 1901 paper.  In the class, I distribute English-translation of this classic paper, and go over the broad outline.  I point out interesting terminologies like “complexion” that Planck used.  Also, Planck’s N and P correspond to w and N in our textbook’s notation, respectively.  Planck’s paper ends with experimental estimates for h and k.

One of the big science news in 2018 was the re-definition of SI units, by fixing the values of the fundamental constants, including h and k.  After ~100 years since the beginning of quantum mechanics and modern statistical mechanics by Planck and Boltzmann, the constants that are named after them have been deemed so fundamental that the units of mass (kg) and temperature (K) have now been defined in terms of their values.  What a big paradigm shift!  See nist.gov for more details.

from NIST.gov, showing the defining constants of the SI units.
from NIST.gov, showing the defining constants of the SI units.