No hand-waving allowed
Finished my MS degree at Wisconsin - Madison, traveling for the summer, and job-hunting

I had updated minimally throughout the semester, but since then I have a number of updates to catch up on. As usual, I am only publishing on this website work that I typesetted. I took two courses during my final semester. And, although I never announce matters like this I am happy, and do not see it too improper, to acknowledge that I ended up my final semester ("ever") on a high note, in that I 4.0'd this semester! Specific updates since last time include:
NEEP 548 -- Engineering Analysis II
- Green's functions solutions to various ordinary differential equations. The problems are an adaption of those from Haberman problem 9.3.12.
Homework 5: Multiple-scale Analysis
- Bender & Orszag 11.11
- Bender & Orszag 11.14
- Method of images solutions to Poisson's equation in semi-infinite domains in two and three dimensions with mixed boundary conditions
- Method of images solutions to the heat equation, finite domain, Neumann boundary conditions
- Method of characteristics solutions to the wave equation, semi-infinite domain
NEEP 741-- Interaction of Radiation with Matter, aka "the second half of Jackson"
- Frame invariance of electric and magnetic fields
- Quadratic Lorentz invariants in electric/magnetic fields
- 4-vector solution to a kinematics problem
- Energy loss of alpha particles in a carbon medium
- Jackson 14.4
- Energy spectrum of a linear antenna with a prescribed current
- Jackson 14.9
- Jackson 15.9
- Classical lifetime of an electron in a Bohr atom.
EMA 201 -- Statics
- My career as a TA has come to a close, I have uploaded many materials I have assembled and/or developed over the years so that it may be of use to any future students or TAs. Materials include a number of problems, detailed solutions, slideshow presentations, a sample design report, design report/technical writing advice, and more. I purposefully did not upload any of the design project solutions. While the solution manual has been leaked, this manual does not contain solutions for these problems. If you are a TA/instructor, and would like a copy of my solutions, please send me an email and I would be happy to provide you with any of them. These solutions are in a number of forms: typesetted documents with accompanying plots, excel spreadsheets, and/or matlab scripts.
Guest contribution: Law of Averages proof
- Kyle Herrity provides a proof to a classic law of large numbers, that is, that for a sufficiently large sample size the sample mean converges to the expected mean. Thank you Kyle!
Those two take-home finals from the top two classes were the very last works I produced as a graduate student at the University of Wisconsin - Madison. Remember what kind of students we used to be? Really, the difference between these two works and my nascent efforts as an undergraduate student speaks so much on the behalf of the effect of education. Especially in that 741 final exam, I remember being at the age and phase when some elementary physics problems that took but a few lines of algebra seemed laborious, and to now knock out a 34 page writeup of nontrivial problems in but a few days is certainly something meaningful. I really am thankful to all my professors, and institutions for so actively steer me on this course. I am learning much more every day and by no means do I mean to insinuate that I have reached a finish line by any means, I just mean to take a pause and juxtapose levels of progress while I veer down a different avenue.
Thanks everyone for reading and visiting. This break from academia will surely not mark a simultaneous hiatus from updates, I will still be around, but the updates may take a more blog-like turn as opposed to the usual academic works I am able to post by way of assignment. Over the years since this site's inception I have received so many kind emails from students around the world, professors, and even researchers who I am thankful to who have taken time out of their day to forward me papers or links regarding clearing up uncertainties I may have expressed throughout miscellaneous documentation posted on here, or questioning how I obtained particular plots, or even challenging interpretations I have put forth. I really find it encouraging and warming to see the candidness in communication, that people would not only benefit from anything they find on this site, but that they could be so friendly as to let me know how it helped and even upload these documents on share sites to spread them around. Others have taken the time to correct me, pose discussion points via email about tenets I have pushed forth in my work, or to provide me with citations that may elucidate something that maybe even I was confused on. I really feel a sense of community from making this site that I never imagined would reach me just by me publishing some of my works somewhere in an odd corner of the internet. How awesome is it to receive emails from researchers around the world, with oftentimes no intent but to help *me* learn more? Thank you to each and every one of your who have contacted me over the years, I appreciated every email, each discussion point, paper, link, etc. that has come my way. I have had tremendous trouble locating research experience throughout my graduate career, and it is part of the reason why I am taking a break and apprehend this issue directly by seeking research experience in a job, but I have felt like this website has contributed towards filling some of that deficit by allowing me interaction with a global community.
I am traveling to Latin America in a couple days for a duration of 15 days. Otherwise I am on the job hunt for principally a plasma physics research position in fusion sciences. I have upgraded my resume from a usual ms word document to a TeX version at long last. Thanks is deserving to Derek Hildreth who was generous enough to provide his source .tex file.
Outside of that, peace out Madison. Thanks for the times, education, friends, relationships, and mentors. I will miss you grad school (kind of), see you again someday (maybe). Take care everyone, and all the best.
- David
Figure lol - "Looking for a more compact answer"? That makes two of us.
(full size answer, problem statement [NEEP 741, Hegna])
Asymptotic and perturbation methods for solving partial and ordinary differential equations (boundary layer theory, WKB approximations, etc.) are discussed in this class. The course follows the text by Bender & Orszag (BO).
- Homework 1 (partial assignment, covers chapter 3 ["Approximate solution of linear differential equations"] of BO)
- Bender & Orszag problem 3.8
- Take-home exam 1 (boundary layer theory and WKB methods)
- The problems in this course are short enough that I will try to typeset most of my assignments (as opposed to the course below), so stay tuned.
Merhaba arkadaşlar~
안녕하세요 again!
I just came back from a fantastic summer interning at Lawrence Livermore National Lab in California, I will publish documentation relating to my work there whenever it gets cleared by security.
As is evident and expected, I was a little bit more than a little busy during the summer, and ended up not fulfilling any of the numerous ambitions I had in mind for this website (as discussed in the previous update). However, I do still intend to produce these materials in the future. I am here in Madison for my second year of graduate school. Anyway, I am not sure how I feel about these updates becoming slightly blog-like, so I am going to stop now and think about it later, where later = winter break or some other time.
To all of my students this year: please refer to section 'For Students' on the menu bar on the left for materials related to discussion sections. This section will be updated with more material as we progress in the semester. You may find my contact information on the left as well.
Also, thanks very much to everyone who has sent me such kind emails about how itcanbeshown.com has been useful for them, or how they enjoyed it, or for whatever other reason. It has been really nice to hear from you all
It has been almost an entire year since I have updated, meaning I have replete material to publish. I am in LOLgrad school now over here at University of Wisconsin - Madison at their Nuke department, studying plasmas and fusion. Accordingly, an indicative new section has been added to the lefthand navigational menu. As far as particular updates, I just went through Jackson E&M, and am considering typesetting some of my solutions to particular problems that were of considerable magnitude. In regards to plasmas topics, I intend to write up a document for the solution to spatial Landau damping (i.e. what is actually observed in experiment), some MHD derivations, and some kinetic theory of plasmas work related to deriving tensor elements of a hot plasma. A lot of work ahead of me, so whenever those come to fruition is subject to question, but I will try to finish all of these planned updates before the summer is over.
Japan was entirely splendid by the way!
In other news, I am moving towards rendering this website into having a mesh of personal/professional content. Of course, as it stands, I "do not have a facebook/myspace/etc." <_<. Additionally, I would like to extend the breadth of content on this site to allow a place for some foreign language instructional documents targetted specifically at polyglot types out there (what what).
That is all for now. Hope you all have been well, take care, peace, and until next time!