Posts

May 01, 2015

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5:01 AM | Linkage
Some good discussions this time over on G+, especially for the vote-off-the-island post but also on the golden spiral, P=NP counterexample, and election-system posts.3d rendered art by Joey Camacho (G+)Rivers don't actually approximate semicircles (G+)Intimidating researchers from discussing known vulnerabilities in fly-by-wire systems (G+)ICALP accepted papers (G+)Animations of mechanical linkages (G+)If impact factors are so obviously irrelevant, why do we still use them? (G+)California MOOC […]

April 21, 2015

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1:11 AM | Perturbing weighted elements to make set weights distinct
Suppose you have a polynomial-time algorithm that operates on sets of weighted elements, and involves comparisons of the weights of different sets. (This describes many different algorithms for shortest paths, minimum spanning trees, minimum weight matchings, closures, etc.) But suppose also that your algorithm is only guaranteed to work correctly when different sets always have distinct total weights. When comparisons could come out equal, your algorithm could crash or produce incorrect […]

April 17, 2015

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7:16 AM | The red door
I couldn't resist photographing this door to a lecture hall in the science sector of the UCI campus. I'm not sure what the pink paint brushmarks are: vandalism? Rustoleum? But they make a nice pattern.( Another shot of the same door )
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1:08 AM | Parametric closures
My latest arXiv preprint, The Parametric Closure Problem (arXiv:1504.04073, to appear at WADS) concerns an old optimization problem that can be used, among other applications, in the planning process for open-pit mining.Suppose you have the mining rights to a three-dimensional patch of earth and rock, in which the ore is of a type and depth that make it appropriate to remove the ore by digging down to it from above rather than by tunneling. You can make a three-dimensional model of your mining […]

April 16, 2015

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5:41 AM | Linkage for tax day
Fractal flat torus flyover video (G+) The author of the plagiarized article on plagiarism turns out to have himself been a past victim of plagiarism (G+) 2048 NP-hardness (G+) Michael Kukla's organically-shaped stone sculpture (G+) Save water: shower with a bucket (G+) The reach of the all-seeing eye extends to the land of morning calm (G+) CCCG call for papers (G+) Layered cut-glass sculpture by Niyoko Ikuta (G+) Editing Wikipedia as course assignment (G+) WADS accepted papers (G+) The fractal […]
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