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ece 515, the week of August 25

No class August 26!

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math 285, the week of August 25

Brash up your calculus. Review Chapter 1.1. Listen to the first lecture.

Homework (due by Monday, 9.1):

  1. For which \(x\) there exists a real solution to
    \[
    y^2-4xy+4=0?
    \]
  2. Simplify
    \[
    \frac{\sin(x+y)-\sin(x-y)}{\sin(y)}.
    \]
  3. Solve differential equations
    \[
    y’=\sin(2x+3)
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hyperbolic geometry of Google maps


\(\def\Real{\mathbb{R}}
\def\views{\mathbb{G}}
\def\earth{\mathbb{E}}
\def\hsp{\mathbb{H}}
\)

Google Maps and the Space of Views

Let’s consider the geometry hidden behind one of the best user interfaces in mobile apps ever, – the smartphone maps, the ones which you can swipe, flick and …

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TDA at HCC

This summer Yura Mileyko and I gave a tutorial on Topological Data Analysis at ISIT 2014. It was intended as a gentle introduction aimed at people who never heard about homologies (outside of, say, biology) – and there were …

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big bad machine

Is installed in the department: it has reasonable processor, but most importantly, hundreds Gigs of RAM. If you have some really big bad computing to do, we might be able to accommodate some requests.

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Voice of Russia puts Urbana on the war map (never mind the grammar or arithmetic)

From voiceofrussia.com:

“A new wave of a massive D-Dos attack hit our site at 1 o’clock pm last night,” the organizers of the Crimean referendum have just reported.
“Our IT safety experts managed to find out where those attacks

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robotic yoga

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unimodal category


We say that a continuous function is unimodal if all the upper excursion sets
\(e_f(c):=\{f≥c\}\) are contractible. For a nonnegative function
\(f:\mathbb{R}^d\to\mathbb{R}_+\) with compact support its unimodal category UCat(f) as the least number \(u\) of summands in a decomposition \(f=\sum_{i=1}^u …

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linear search


triangle_rich
Linear search problems deals with locating an object hidden on a half line (“long road”) by an absent-minded robot which gather everything it sees (see, e.g. here for more details). A program for the robot is a sequence \(0<x_1<x_2<\ldots\) of …

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