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Comment Re:Screw other people (Score 1) 800

Your first duty is always to the other road users.

Therefore, in a crash the first thing that you avoid are unprotected trafficants, first pedestians and then motorcyclists and by analogy it is reasonably to then avoid such cars as have the least protection. To drive into a pedestrian to reduce harm to oneself in a crash is not acceptable.

Comment Programming is unlikely to be a primary profession (Score 1) 581

It's clear that not every job lost can be replaced with a programming job. To imagine a single rather small profession as the profession into which coal miners, plant engineers that become redundant due to equipment that breaks less often and so on isn't sensible.

I don't feel that the matter is that coal miners aren't intellectual enough, but that the need for software isn't infinite. Finding productive work for people is going to require finding completely new ways for humans to contribute and to do so is going to be very difficult. Trying to let people who have been laid off study and learn something new is a good path for a society, but I don't believe that there is enough programming to be done for programming to be sufficient.

Comment Re:The world is changing. (Score 1) 224

I remember reading Rudin's little analysis book and reading it on the principle that it was appropriate to stay on each page for about 30 minutes, or until all proofs were remembered and could be reproduced at will, following a recommendation of some famous mathematician whose name I can't recall (but for some reason I think that it was Hardy or Littlewood).

There's also apparently such a recommendation in Axler's linear algebra book, but there the recommendation is that one should take no less than an hour per page. I think that this recommendation may be excessive though and I don't think that either of these should be followed strictly for all pages, but they're a good warning for seeing that one is trying to read too fast.

Comment Re: Truly (Score 1) 99

No, it's fairly good. A smith needs substantial infrastructure to do what he does, his whole smithy with numerous tools which represent a high capital cost. A carpenter does not have quite the same capital cost although an analogy with a carpenter instead of a smith does have definite appeal. Especially now that I come to think of Hogarth print in which there is an image of a carpenter pawning his saw.

Comment Re: Truly (Score 1) 99

A captain rarely owns the ship the ship he captains though.

I think that what one ought to imagine here is something like a smith who doesn't own his tools, but has access to tools which he does not control, with his tool access and the tool access of many other smiths entirely at the mercy of some large tool-owner.

Comment Re:Wake up SAE. Standardize TREs now. (Score 1) 191

I feel that adopting a design in order to bypass a legitimate regulation is rather bad.

There's also a whole lot of inherent problems with towed generators: A car towing something is not maneuverable and unlikely to pass the elk test, there will be unnecessary drag and towed generator will be heavy, since it will need to have wheels and some sort of shell. Series hybrids are already a fairly established thing and I do not believe and are the reasonable solution. The BMW i3 already has an optional built in generator (a two-cylinder petrol engine), Jaguar made a concept with two turbines some years ago and the Chevrolet Volt is also a series hybrid.

Consequently, good systems solving the range problems of electric cars have been in production for years so there's no reason to go for a bad system like a towed range extender.

Comment Re:It's a status thing (Score 3, Interesting) 717

There's an Swedish radical socialist song about this from 1972, by a band called Blå Tåget: "Each hand knows what the other does" (which of course, is a clever title in Swedish). Below is a somewhat crappy translation (the original fits a rhyme scheme, and a metre).

"The capital raises the rents, and the state the rent benefits
In this way one fiddle with the Iron Law of Wages
and even pay less wages than the price of food and rent,
for the state merrily pitches in should the living expenses grow to great".

They then go on to give further examples of how a welfare society merely masks fundamental injustices in capitalism and how it is something which alleviates symptoms instead of going for democratic control of the means of production. I've long wanted to translate this song into English properly, because it's insightful and the ideas in it are somewhat foreign to most English speakers.

Comment Re:Your Boss (Score 1) 717

You can't stop though, because if others continue there is no reason for other employers to offer better conditions.

A corporation is certainly in some part dependent on its employees, but if they hold any real resource, like say, a mine, oil wells or an expensive factory then they are likely to be able to find other people to exploit. Your proposal of a combination of boycotts and quitting is likely to lead to a small improvement, but it won't be all that substantial, especially in an economy with a labour surplus.

Comment Re:see also, increasing the # of H1Bs awarded (Score 2) 462

This isn't really true. Any reasonably coherent group has common interests and engineers or workers in general certainly are such groups.

The degree to which ones relationship with ones employer is voluntary is also fairly doubtful. It is voluntary only in that there is a possibility to choose among employers, but even if they were in perfect competition this does not make making the choice voluntary. That is only voluntary as long as one has the resources to become ones own employer.

The engineers at google might have those resources if they banded together and formed themselves into a worker co-operative, or had a union which regularly threatened that they would form themselves into such an entity, and that might give them an equitable share of their production. In more capital intensive industries the workers, even collectively can't do this, and must resort to threatening strikes. These are policies necessary for getting a good share of wages even in competitive markets and when people form cartels against people who don't even have a union there will be a reduction in wages.

A house seller might be a friendly adversary in transaction, but in a world where ordinary people do not own houses, but rent them with no realistic chance of every buying, it ceases to be quite the same situation and that is more akin to the situation that most workers are in with respect to those who own capital-intensive companies and land.

Comment Re:Energy density. (Score 1) 734

While cars are about 30% efficient, this is far from the Carnot limit. Even in Otto cycle engines, like in typical car engines a compression ratio of 10:1 is enough to produce a theoretical cycle efficiency of 60% (http://scienceworld.wolfram.com/physics/OttoCycle.html).

Furthermore, not every car uses the Otto cycle and things like gas turbines (Brayton cycle), Diesel engines (Diesel cycle) do exist. Even existing turbo-compound diesel engines like the 3rd generation Diesel-Ethanol Scania 9-litre engine achieve thermal efficiencies of 43-44%, depending on fuel. There are also all sorts of potential future innovations, such as camless engines which have the potential to make engines smaller and lighter as well as increasing valve control so that more efficient cycles can be implemented. Then there's the possibility of adding additional power strokes, for example, by adding additional cylinders in which exhaust gases are further expanded, or by using water injection followed by two additional strokes to make use of the expanding steam.

Beyond this there are really experimental things like wave rotor engines and other inventions that may well continue to improve car engines to keep them competitive for well into the future, especially for people who like light vehicles with high power-to-weight ratio. Of course, batteries will still make sense, since hybrid configurations may permit engines to run at fixed loads and batteries might become lighter I still.

I especially doubt whether fully electric trucks and busses, a thus whether electric *vehicles* to achieve the goods and people moving capacities of gasoline powered vehicles, are practical at all, although I have little doubt that they will likely become hybrids.

Comment Re:Test scores (Score 1) 715

I have strong doubts whether learning the multiplication table as a table is useful (although showing people a multiplication table to demonstrate that these small multiplications can be tabulated is sort of okay). If done as rote memorization it does however not seem like real mathematics.

It might serve as an excuse to give people experience in applying the commutative and distributive laws of multiplication, but I imagine that it's fairly rare that it's done that way and that it's usually treated as rote memorization. However, if you do things correctly you can perform multiplications about as quickly as someone who knows the multiplication table by only memorizing that 7*7=49, how to double a number, how to halve a number, how to triple and number and how to divide a number by three. Then you can compute 9x as 3(3x), 5x as 10x/2, 8x as 2(2(2x)) and all the others. If you want to go to multiplying all numbers up to 12 you can choose either to compute 11x as 10x+x or by additionally memorizing that 11*11=121.

This is good exercise if it's done right, but I think that the point of it is to understand the commutative and distributive laws of multiplication as preparation for algebra. If one after doing this wants to learn to compute things quickly one will, once one understands the general principles have no difficulties learning to do so.

Comment Re:Tiny little airbags like the polystyrene foam? (Score 3, Interesting) 317

Aluminium honeycomb is used as a single-use shock absorber and deforms very evenly and I imagine that the same thing is true of this paper stuff. It's fairly impressive, but is best seen in an image: http://commons.wikimedia.org/wiki/File:Single-use_crushable_aluminium_honeycomb_shock_absorber.jpg.

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