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Comment Re:And three: (Score 1) 203

Health-care and teaching appear much more expensive today because manufactured goods cost much less. If you look at where people are employed and making a good living, from 1960 to today, it quickly becomes obvious that certain sectors, like manufacturing, have became much smaller due to productivity improvements. Other sectors, like teaching and health care have not benefited from the productivity miracle the same extent. Additionally, certain intangible sectors of the economy that have went from non-existent in 1960 to a significant expenditure today. I'm thinking of finance, including credit cards and student loans, the software industry, and cell/internet companies. These companies have much higher worker-productivity levels than manufacturing has ever achieved. As a result, they employ very few people per profit developed.

Assume that all of the good paying jobs in the economy pay roughly the same amount, and the workers are distributed based on productivity and the realistic material needs/wants levels. It quickly becomes obvious that health care and teaching must be a larger portion of the economy in terms of workers, because we want health-care and education and therefore need the workers in these occupations. On the other hand, manufacturing, software and finance must be smaller portion of the economy in terms of workers, because they need fewer workers and there is an upper limit on the output we could want from these sectors. This macro-economic model applies at both large and small scales. If the overall economy has lots of workers in health-care, then the average person must be spending lots of money in that sector. The same applies to education.

To make it to the post-industrial utopia, we need to:
a) automate health-care and teaching in much the same way we have automated manufacturing, and
b) ensure that the people that lack high-income skill-sets remain useful and contributing members of the economy.

I tend to think America will achieve (a). (b) is tougher.

Comment Re:is this an article or quesiont ?! (Score 1) 288

It's a question without a good answer. There doesn't appear to be a "permanently prevent Windows 10 upgrade" switch anywhere.

This could be a business opportunity. Write a piece of software that automatically finds and suppresses any attempts to update to Windows 10.

Comment Re:Inkjets are a scam (Score 1) 268

Have you looked at the cost per page of the new lasers? The same companies that brought us hideously priced ink for inkjets have created even more expensive toner for laser printers.

I don't purchase a new printer until I have computed the cost per page of the toner/ink. Often, the heavier "business" class devices have a much lower cost/page on the toner cartridges, and the savings often pays for itself in very short times (on the order of 3 to 4 sets of cartridge changes.) Also, colour lasers are more expensive to run than black and white laser printers. Beyond that, inkjets might be cheaper, or they might not.

Comment This is to be expected, and affects many printers (Score 4, Interesting) 268

The ink-jet cartridges measure their print out volume based on the number of droplets deposited. A +/- 5% change in ink droplet diameter represents a +/- 15% change in volume. When dealing with really small feature sizes, variable temperatures, and variable viscosities, it is really tough to control droplet diameter exactly. The result is that the ink-cartridge manufacturers need to overfill their cartridges to guarantee that some customer in some corner case doesn't experience a rash of cartridges that run out early.

This tactic is kind of like the hand-soap people that sell a 1 L container of soap with a hand-pump that only works for the first 950 mL. If we can see the soap in the container, we get annoyed because of the 50 mL of waste. However, the ink-cartridge people hide the amount of ink left in the "empty" cartridge, so we don't notice the waste.

Of course, when you are dealing with professional cartridges, and print-outs that can be worth big money, the printer cartridge manufacturers have to guarantee that the ink doesn't run out. The cheapest way to do this is to add a little bit of ink.

In the case of consumer cartridges, HP, Lexmark, and Epson would be deeply upset if a bunch of the customers complained about "empty" cartridges that still said they had 5% capacity left. To prevent complaints, add a little bit of ink ...

Adding a little ink makes everyone happy, until someone actually looks at what is left in the "empty" cartridges, and measures it with sufficiently accurate equipment to realize how much "extra" ink is left.

Comment I'm not surprised (Score 4, Insightful) 62

The SLS exists to give pork to established NASA contractors. SpaceX is trying to get stuff into space cheaply.

SpaceX is centralized in a few districts so it gets relatively little support. On the other hand, the SLS has pork divided up over the whole country. Thus, if you are a politician, and want pork, you want to support the SLS. The fact that the SLS makes no scientific or financial sense whatsoever, does not factor into the decision to vote against SpaceX. To bring pork to your district, SLS is the correct program.

Unfortunately, SLS has went the way of many of the more recent military purchase programs. Yes, the F-35 can be built, but why? Yes the SLS can be built, but is this really the best way? do we really need it? Given SpaceX's development trajectory, will the SLS ever be needed? Really needed?

Comment Re:Programmed behaviour is programmed behaviour. (Score 5, Interesting) 451

If it can't make it's way through a junction where the drivers are following the rules, that's bad programming. If it can't make it's way through a junction where other drivers don't come to a complete halt for it, it's not fit to be on the road with other drivers.

The problem is that people don't follow rules. We follow approximations of the rules. For instance, my driver's handbook described the correct way to deal with yielding at a four-way stop as "yield to the person on the right." For a computer, that's an obvious deadlock situation, or worse - an obvious mistake. If four cars are parked at a four way stop, and each car yields to the car on the right, then (a) a situation could occur where no one goes anywhere, and (b) if the individual cars only pay attention to the person on the right, then they could hit an on-coming car turning left, or the car on the left turning left. People process the "yield to the person on the right" rule into something much more complex.

People use a number of complex behaviours at four-way stops. Firstly, the wave of the hand, or the nod of the head to indicate that you yield to the other driver is an important signal. Secondly, in my jurisdiction, 90% of the four way stops are done on a first-come first-served basis. Lastly, and this is the bit I don't understand, often people yield to the person on the left. The actual system of navigating a four-way stop is much more complex than what an initial computer implementation might be.

Comment Re:Pay more, get more (Score 3, Insightful) 152

The article specifically states that rank in sponsored links correlates to advertising spend, which I would expect.

I would also expect a weaker correlation between page rank and advertising spend in the normal links. Firstly, a site with significant advertising spend will hopefully generate more hits, and this should translate into page-rank. Secondly, I would expect a site with significant advertising spend to spend more on its site, which hopefully results in a more informative and more useful site. In turn, this should result in a weak correlation between advertising spend and page rank. Lastly, some correlation probably exists between advertising spending, and hits from the google search spider. This may translate into improved page rank for trending topics.

In all, I would be surprised if there were not correlations between advertising spend and Google page rank. What I do like from Google is that they clearly label the sponsored versus non-sponsored links. Also, Google also has a number of non-commercial sites at the top of many search suggestions, which indicates that they treat sites without advertising spend reasonably.

Comment Re:From TFA: bit-exact or not? (Score 3, Interesting) 174

The grandparent poster is talking about compressing videos. If something is known about the data being encoded, then it is trivial to show that you can exceed the performance of arithmetic coding, because arithmetic coding makes no assumptions about the underlying message.

For instance, suppose I was encoding short sequences of positions that are random integer multiples of pi. Expressed as decimal or binary numbers, the message will seem highly random, because of the multiplication by an irrational number (pi). However, if I can back out the randomness introduced by pi, then the compression of the resulting algorithm can be huge.

The same applies to video. If it is possible to bring more knowledge of the problem domain to the application, then it is possible to do better on encoding. Especially with real-life video, there are endless cheats to optimize compression. Also, Dropbox may not be limited by real-time encoding. Drop-box might not even need intermediate frames to deal with fast-forward and out-of-order viewing. Dropbox may be solely interested in creating an exact image of the original file. Knowing the application affects compression dramatically.

Lastly, application specific cheats can save real-world companies and individuals money and time. Practical improvements count as advancements too.

Comment Re:Traditional internal facing IT shop .. (Score 2) 198

They could be doing a Citrix-like thing where everyone is logging on to server-housed remote instances. If each instance was one VMWare VM, then 3,000 employees and 1500 VMWare instances makes sense.

They could also be a company where each corporate customer, or groups of individual customers, require their own virtual server. For example: an SaaS accounting firm similar to FreshBooks may have a separate virtual server for every corporate customer, or Blizzard where groups of users have their own dungeon.

Otherwise, even for a IT company, they have the IT infrastructure from hell. I can't imagine 1500 different server applications in a company of 3,000 people.

Comment Re:Use RTGs for ion propulsion then comm. (Score 1, Informative) 77

RTGs are being phased out because (a) the probes need more power than ever with modern computers, and (b) because of environmental concerns. Unfortunately, most of the environmental concerns revolve around the word "Plutonium" and the much more dangerous Plutonium-239.

The best RTGs use a chemically locked Plutonium-238 Oxide that is probably one of the safest fuel sources ever invented. The stuff is non-reactive ceramic that is almost indestructible, and is readily rejected by the human body if ingested. It's not even particularly radioactive, as radio-active isotopes go, because to make the RTG last for a long period of time, it is necessary to use an isotope with a sufficiently long-lived half-life characteristic. Plutonium-238 Oxide is the polar opposite of the more typical dangers from Plutonium-239 that everyone worries about.

See RTG generators and plutonium oxide for more information.

Comment Re:They've only just discovered this? (Score 1) 73

On error, dynamic_cast returns NULL for pointers, and an exception for references. From cppreference:

If the cast is successful, dynamic_cast returns a value of type new_type. If the cast fails and new_type is a pointer type, it returns a null pointer of that type. If the cast fails and new_type is a reference type, it throws an exception that matches a handler of type std::bad_cast.

Comment Self-Checking Code (Score 3, Insightful) 285

I gave up on the concept that I would be able to write and debug programs correctly the first time. Now all the central data structures in any long-lived control system get error-checking code added to them. For example, the sorted-list code is built with a checker to ensure it stays in order. The communications code gets error-checking. The PID controllers get min/max testing, etc.

Every once in a while I come across a bugs that are not in the source code. Often they are compiler errors. Sometimes the bugs involve a rare C/C++ or operating system eccentricity. Sometimes the errors are caused by obscure library changes. Sometimes they are hardware errors.

Especially with the embedded micro-controllers, I leave the consistency checking code in, because you just can't assume the everything always works. The nature of software bugs change with time, and it is not always in the way a programmer would expect. I am frequently surprised by how obscure some of the bugs are.

Comment Re:Core considerations (Score 1) 150

Per core or Per CPU software pricing can dominate the cost calculation. We have a CFD application, and we were considering boosting the hardware. One look at the software costs discouraged us.

A costly complication is that 3-D CFD (or FEA), is an O(n^3) problem. Doubling the mesh density means 2^3=8 times the CPU time. An increase of 10 times in the mesh density requires 10^3=1000 times the CPU time. If you are pushing the extreme, small changes in the mesh density have significant cost impacts.

It makes me wonder how many research groups are paying full-cost for the commercial CFD packages. Many universities, some quasi-government labs, and many small startups will not have the money for the full-price commercial packages.

Comment Re: How much you got? (Score 1) 184

MariaDB. Google switched from MySQL to Oracle to MySQL to Google F1 for it's AdWords technology. See the wiki page on Adwords. Since then, many companies, including Google have switched their smaller MySQL databases to MariaDB.

There is an interesting account of the Google Oracle migration at the wayback machine.

Dinosaurs aren't extinct. They've just learned to hide in the trees.