Earth currents

Five hundred and seventeen for one.  That’s more like it.  Looking forward to more of the same in Adelaide. So, physics. Last week I was doing a bit of work in the lab with a  student, trying to track down why his instrumentation wasn’t working. We’re still at it; what he’s trying to do is quite […]

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Analogue Computing

What a dismal and predictable start to the Ashes. Turn your back on the computer screen for five minutes and suddenly England have lost three wickets. Anyway, yesterday I was in Auckland, talking about research progress with a group that we’ve had strong links with in the past. (By ‘we’ I mean the Waikato cortical modelling group). One […]

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Wallpaper lattice confusion

I got home from work last night to discover the decorator still hard at work, putting up the ‘feature’ wallpaper on one fairly small section of wall. He said he’d been struggling for the last hour trying to find the repeat in the pattern. It’s a dark paper, with detailed but low-contrast outlines of flowers in […]

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Learning outcomes

This week I’ve had three fairly lively discussions about learning outcomes in our university papers.  (It’s well blogged already – e.g. here, but I’ll add some things to the mix). The concept is hardly new, but it is only just being given a really wide profile here at Waikato. Although many individual teachers, and many […]

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Negative Resistance

I was having a conversation last week with a student about negative resistances (in an electronics context). These are just as they sound – to send a current from terminal A to terminal B you have to apply a higher potential to terminal B than terminal A.  Sounds backwards?  Yes – it is. That’s why […]

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Mouse-be-gone (-be-gone)

Here’s some interesting stuff courtesy of the mighty google on yesterday’s post.   http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1033&context=nwrcrepellants   It’s an old (1997) report on ‘electronic’ pest control devices. On ‘electromagnetic’ devices, it comments "Laboratory efficacy tests on the control of Norway rats … indicated definitively that such devices have no effect on feeding, drinking, mating or infestation patterns."  Hmmm.  […]

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Electromagnetic Pest Repellent

I saw in the newspaper yesterday an advert for an ‘ultrasonic and electromagnetic’ mouse and rat repeller. That got me interested. The ultrasonic bit seems to be plausible enough – I don’t know much about rodent ear physiology, but I’m willing to believe they can hear sounds at higher frequency to us and to dogs […]

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