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jurjenh

434 karma · joined March 20, 2009

Live and work in Waiuku, New Zealand. Husband to a fantastic woman, and father of one beautiful daughter. Currently a cabinet maker (family business) - but previously worked as an engineer - I studied electronic engineering at Canterbury University (NZ).

Interested in programming (javascript, clojure, c, python) CAD, CAM, surfing, surf life saving, learning and making stuff.

gmail me at: jurjen.haitsma

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jurjenh··on Teach yourself programming in ten years (1998)
You are obviously with them in the wrong room....

Once you know them for who/what they are, and you learn to be comfortable enough with not following them closely, or not knowing what the hip thing is right now, then you can learn to let go of that (almost) insatiable need to keep up. Let them have the room - and the mental energy it requires.

jurjenh··on SpaceX Refused to Move Satellite at Risk of Collision with a European Satellite
I'm not entirely convinced this is the argument.

From what I've read so far, it seems that ESA was uncomfortable with the possibility of a collision to a degree that SpaceX could possibly be quite comfortable with - ESA wants > 1km distance, whereas SpaceX might be comfortable with much closer - they are quite different constellations.

Who has the right to dictate who has priority / which criteria is the right one?

I'm going to assume that the cost of ESA's satellite is much greater than SpaceX's StarLink module so obviously they have much more of an interest in preserving full functionality - BUT avoiding collisions is in everybody's best interests. Who is going to use their fuel? Who has right of way, and to what terms?

jurjenh··on The Most Beautiful Piece of Code That Prints 42
Could be "improved"

  #define SIX 1+8
  #define NINE 5+1
jurjenh··on Joint 3D Face Reconstruction
That made me wonder about what would happen if google started grouping concepts (eg words for grandmother in other languages will almost certainly give you differing results) rather than words...

Possibly (probably) the cognitive load on people might lead to bad A/B test results, but it would be a curious thing to explore - cultural bias would get a bit of a beating I'd imagine.

jurjenh··on SpaceX’s Falcon Heavy successfully launches
It always comes in slightly to the side of the barge and as part of the landing burn it does a final sideways correction. I believe it was for this kind of situation - or one where the final burn doesn't even happen.
jurjenh··on Google Maps' Moat
Didn't google earth have exactly this in the early days? I can't remember exact details, but pretty sure it was an easter egg - ctrl + alt + a would launch it.
jurjenh··on ADSL over wet string
Also reminds me of ethernet over barbed wire. Seems like similar things have been done for a long time...

http://www.sigcon.com/Pubs/edn/SoGoodBarbedWire.htm

jurjenh··on Ford Pilots New Exoskeleton to Help Lessen Chance of Worker Fatigue, Injury
"The non-powered vest offers protection and support against fatigue and injury by reducing the stress and strain"

Would love to see how this works and maintains an adequate range of motion so as to not get in the way. Seems like it adds rigidity so that the weight is shared by the exoskeleton.

jurjenh··on WebVR Experiments
Pretty sure Wernher von Braun isn't available any more though [x], in fact I think you're going to have a real hard time with many of the other principals. Principles though seem to be potentially an easier route.

Either way, I'd back that category in a heartbeat, though not sure if it could be completed in the duration of a normal games cycle... In a way it's been started already with the google lunar x prize [o] though that's been running a little longer than your typical games...

[x] https://en.wikipedia.org/wiki/Wernher_von_Braun

[o] http://lunar.xprize.org/

jurjenh··on SpaceX to Send Privately Crewed Dragon Spacecraft Beyond the Moon Next Year
I believe that comment is more or less based on the shuttle landing and/or the soyuz capsules (eg parachutes) - but as far as I can tell, SpaceX is the only one currently capable (and using) propulsive landing on earth - so essentially they've already leapfrogged the grey zone to a large extent.

Makes me wonder whether testing a propulsive landing on an airborne drone barge is feasible? A blimp with a well-insulated large pad on the top - though I'm not sure how you'd effectively anchor it in the air - probably a active propulsion system as well.

jurjenh··on Things You Notice When You Quit the News
Except for things like volcanoes and earthquakes... Though grantedly that is a different kind of excitement.

You're still subject to much the same kind of media merry-go-round, and subjectively is probably not even that far away.

jurjenh··on Quake's Lighting Model: Surface Caching (1996)
I would say on the whole, yes - that is actually true. Now you only need one "smart" person to program up the machinery, whereas in the past you did need multiple skilled craftsmen in a variety of roles - not exactly apples vs apples, but I think that one of the unfortunate side effects of too much specialization is a lack of a broad knowledge base that lets you apply skills from one field in a different area.
jurjenh··on Dunning-Kruger and other memes (2015)
The way I've come to see it is "The less you know about a subject, the less you think you don't know."

In other words, you have no solid grasp on the field and so cannot make an effective guess at your ability in the field - so go for middle of the road and that's possibly your best statistical guess...

jurjenh··on New Bug Found in Widely Used OpenSSL Encryption
I'm pretty sure the implication is that the big corporates don't care a hoot about open source, the ethics or the model - they'll just take it, the cheaper the better.

The principle and supposed ethic is to share and have some reciprocity - the reality is somewhat different. And we all suffer. Tragedy of the commons, I guess...

jurjenh··on Subtly Bad Things Linux May Be Doing To PostgreSQL
Is there a middle ground here somewhere? In that the kernel developers create some sort of DB specific hooks that allow some of the kernel bypass mechanisms to be implemented?

What are the key things that a kernel bypass version does different? Can these be separated out in a concise way which would lead to multiple DB implementations being able to use these same interfaces? Essentially for any major DB system, you'd want the kernel tailored anyway - you're not going to be doing much else on your DB server (are you?)

jurjenh··on Suspension of NASA contact with Russian entities
Genuine question - was he Ukranian when he went up there? I guess customs for space flight isn't such a concern, but that would be a weird thing to have go down while you're off the planet...
jurjenh··on Tesla Faces New Jersey Challenge as Rule Change Looms
How often do sysadmins actually make the call on what gets bought? For a purchasing dept, they'd probably stop at step 2, get the over-priced product and everyone's happy.

The re-seller is obviously the under-performing part of your exchange, it should be their business to know what they are selling. Most likely it shows the current state of the market - not very many buyers ask these technical questions, hence the experience is not there for the reseller. If you'd want to feel better about it, at least the reseller you've dealt with now has some more knowledge of one of the products they are selling.

jurjenh··on Tesla Faces New Jersey Challenge as Rule Change Looms
There's a relationship management issue there somewhere - supporting one-off small volume sales has a definite cost at some point - someone needs to process and fill the order. Limiting sales to "big" customers means you can spend less time dealing with all the order processes and focus more on a decent product (or decent profits, wherever the focus may lie)
jurjenh··on 2048 AI
Easy to implement in an AI as well. Could try various permutations and see which works best fairly trivially then too, eg up down left right / up left down right / up left right down etc...
jurjenh··on F.lux updated
I've been enjoying spotting the sunset. Can't actually see the sun setting where I live, but the sudden change in hue (blueish to reddish - I've set it quite red) is quite noticeable (pleasing to my eyes).
jurjenh··on A software engineer's website
Is there a noscript type extension that allows you to see the start of the script contents? Or the parts that would be triggered first?

Seems like a sensible option might be to have some sort of button (address bar / extension button) that opens up a pane with the javascript as read-only so its easier to do a quick visual check for "funny business".

jurjenh··on Scale of the Universe
I wonder if it is an instinctive reaction:

a large new space has a lot of unknowns -> some of these unknowns could be dangerous -> a very large new space has a lot more unknowns -> very large spaces are to be feared.

This is based on nothing more than my imagination, but seems like a sensible evolutionary precaution.

jurjenh··on The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light
Wow, that page led me to the fact that there is such a thing as centrifugal force... And all these years spent trying to correct people. Oh well, you live, you learn.

http://en.wikipedia.org/wiki/Photon_sphere

jurjenh··on Could This Baker Solve the Gluten Mystery?
Just googling it (because I've heard it from several places) that the longer rising of bread does start to break down some of the gluten (hence making it easier to digest)

Fermentation of proteins. Some bacteria of the genus Clostridium (putrescent anaerobes) are able to ferment amino acids as well as carbohydrates. These bacteria are better adapted to utilize proteins, which they break down to amino acids by means of proteolytic enzymes; the amino acids are then fermented. The process of protein fermentation is important in the circulation of matter in nature.

source: http://encyclopedia2.thefreedictionary.com/Fermentation+Proc...

jurjenh··on Stolen Camera Finder: uses serial numbers embedded in photo metadata
What about other options? Dead/underperforming pixels seem to be a good fingerprint as well I believe.

Would be a whole different level of identification, but would lead to multiple ways to detect photos taken by the same camera.

jurjenh··on Fungus threatens top banana
I don't think there's a limit, as its part of the natural growth pattern of bananas. Some other species have similar habits - I believe there's an entire forest that is one plant - http://en.wikipedia.org/wiki/Pando_(tree)
jurjenh··on Fungus threatens top banana
Yes - you caught me out there :) but what I had in mind was a small-scale greenhouse - the kind you have in your garden, not the commercial-scale kind. But this brings back the restricted scale that we'd end up with if mass-produced long-distance transport bananas become non-viable.

What I mean with local IS growing plants suited for the climate. So in most cases, tropical is out, unless you can take advantage of specific areas that may have a generally warmer micro-climate to grow these foods. But this implies small scale, as otherwise you'd have to put in acres of greenhouses, at which point shipping may well be a better option.

The thing about our current system is that it is efficient, making long-distance shipping feasible. However, it is not resilient, as it depends on politics and cheap energy. I'm not sure if I'd class that as sustainable just because that's how we've done it for the last 50 or so years...

jurjenh··on Fungus threatens top banana
This is incorrect. You can't breed fertile bananas from the Cavendish, but if somebody kept records of how they got there (crossing which cultivar with what) we could do the same today starting with the original cultivars, which most likely are still around somewhere...

The problem is finding the cultivars and doing the whole experimental process with specific plants and documenting it... Given that bananas grow fairly quickly it is probably relatively do-able. Just need some land and some volunteers... And flying under the radar of the banana companies :)

jurjenh··on Fungus threatens top banana
Yes, but that's not the only way bananas propagate. The fruit is how genetic variability gets introduced, but they also develop shoots from the root system, which eventually grow into trees themselves.

I believe traditionally bananas are grown as the main trunk, then 2 baby shoots at differing maturity. Once the main stem has fruited, it is removed and the next one takes over, at which point another shoot is allowed to develop.

The extra shoots that are removed can be used to start another "family" elsewhere, but has the risk of spreading disease. These days tissue culturing is used, with a much lower risk of spreading disease.

jurjenh··on Fungus threatens top banana
They look much more like passionfruit, but with more solid fleshy material. I think the seeds are hard and inedible, but haven't ever seen them in real life...

Also the cultivated ones have been developed specifically for their transportability and shelf life, with the taste as a lower priority. Hmmm... wonder what those Gros Michel taste like?

http://en.wikipedia.org/wiki/Banana

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