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Comment Re:Peer review doing its job (Score 4, Informative) 73

Communication skills matter in science!

It doesn't matter that you have the invented the greatest algorithm since quicksort if you can't or won't tell other people about it. If you can't convince other people how great your work is, they won't use it, and therefore you won't have contributed to the field. When you die the knowledge disappears, and you might as well never have invented the algorithm in the first place.

Therefore, it is important to convince your audiance that:
- Your algorithm gets the job done. (Proofs)
- Your algorithm is better and/or just different than existing algorithms. (Extensive litterature search so that you can compare your algorithm to existing ones)

Just reporting your algorithm together with a "this is how I do it" doesn't cut it. We researchers don't have the time to examine every claim somebody makes about something in our field.

Comment Re:State of the question (Score 1) 130

Thank you!

I spent two months of my PhD, first trying to find an elusive proof for an obscure bit of math that I needed, that, according to the papers on the topic, was "available in the litterature", and then, after I finally gave it up, I painfully reconstructed the proof.

"Available in the litterature" ticks me off, almost as much as "... from this, it is easily seen that ...".

Comment Re:Simplicity (Score 2) 111

CANbus would be a really bad choice for a control system like this one, since the capacity of the bus [bits/s] is linearly proportional to the inverse of the length of the bus. Because of this CANbus is great for cars, satellites, and other "small" systems, but horrible for large systems that require fast sampling.

Comment Re:Not all companies are the same (Score 2) 285

It's the norm in Scandinavia, so if you just pick a random company there's a good chance they'll be just like that. Also, we usually have a shortage of people with technical degrees (Preferably a masters or equivalent. Just a bachelors won't get you far.), but it's not so pronounced with the current crisis.

Comment Re:Ok. Now what is it in hogsheads per fortnight? (Score 1) 173

If you want the expansion as a volume you could use m^3/(s*m^3), i.e., rate of volumetric expansion per volume of space. m^3/s just gives you a rate of volumetric expansion, it doesn't say anything about the volumetric expansion being faster if you look at a larger volume, or equivalently, things move faster away from you the further away from you they are, i.e., m/(s*m), which is what Hubble's Law is all about.

You can of course calculate the expansion of af known volume of space e.g. the entire universe* or just our galaxy in m^3/s, using the newly reported observation.

*As far as I know, we don't know how big the universe is, or even if the universe is finite, so we couldn't actually calculate this.

Comment Re:The Forever War... (Score 2) 277


I loved Starship Troopers. The whole movie was a brilliant commentary to the political situation in the US, and litteraly dripping with sarcasm. I mean, they even cast the main actors for their horrible acting performance. In that sense it was very true to the book, which, in its own time, was a great commentary on fascism.

Comment Re:Still no reason for putting idiots on the job (Score 1) 96

Sensors that spit out text? Who in their right mind would want that?

SCADA grabs sensor readings from the underlying control system, most likely running on some PLCs, where you have to do calculations on the data in order to feed back control values to the process being controlled.

Now, a PLC is, admittedly, sort of like the general purpose CPU's dumb brother, and the instructions it accepts are rather limited. But, for a number of reasons, they're immensely suited for their task. The single most important one being the ability to safely and easily change a program that is in production. This feature is important because control systems often have to be tuned when they're commisioned, they don't just work out of the box. You have to fiddle with constants in order to get it working, perhaps even change the structure of the control algorithm.

Because we control engineers have to fiddle with the program while it is running, we really don't want to do string to int/float/whatever conversion and the reverse when working on the PLCs. That would just be yet another place where we could scew up horribly, causing a country wide electrical blackout in the proces. It's hard enough as it is, so keep it simple, stupid!

Comment Re:Replication of results? (Score 1) 73

There were two teams at the LHC that independantly came to the conclusion that there was a particle.

And, though you might have been ironic, you caught the exact reason there are two independant sets of sensors, data analysis, etc. (Everything besides the accelerator ring.) Now, a third, completely independant reproduction of the result would be golden, but until we get it we'll have to make do with just a single reproduction of the result.

Comment Re:Quick couple of questions (Score 3, Interesting) 73

Consensus has nothing to do with science. Following the scientific method is science.

And the particle the people at CERN have discovered is consistent with what we believe to be a Higgs boson, and might therefore actually be one. We haven't had time to do enough experiments to tell. The only things we know about the particle is that it's there and that it has a mass of ~126 GeV. We're assuming that it's the Higgs, because the Higgs is the only particle that is missing with a mass in that neighbourhood. (Gravitons ought to be heavier, as do dark matter, etc.)

Comment Re:Doesn't matter in the end (Score 1) 472

A feedback controller is a good example. Sure you can test it against a model, but you just won't know until you've had it running against the hardware. Also, models are expensive, so clients often don't want to pay for their development, but will allow for a bit more debugging and tuning against the hardware instead.

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