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Temporary Classrooms Are Bad For the Environment, and Worse For Kids

impossiblefork Re:Global warming is causing bad grades now (187 comments)

Yes. Performance was also degraded as classroom temperatures reached 30 degrees Celsius. I didn't listen to the full presentation, although there probably wasn't enough in it to ascertain whether they had succeded in separating the effect of CO2 and temperature, but it probably wasn't treated, as the presentation was intended for people who designed ventillation systems.

about 3 months ago
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Temporary Classrooms Are Bad For the Environment, and Worse For Kids

impossiblefork Re:Global warming is causing bad grades now (187 comments)

No, it's actually quite right.

Just yesterday I happened upon a presentation by a company called Swegon, which designs and manufactures ventillation system equipment, in which they showed a material from a British researcher who (I believe on their proposal) had arranged measurements of student performance as a function of class CO2 levels and classroom temperature and the effect on the speed with which students performed diverse simple tasks, like adding numbers, multiplication, etc. and overall it turned out to drop by 30% as CO2 reached the worst levels.

In some schools the CO2 levels reached about 2000 ppm. The idea that this doesn't affect people is ridiculous and properly designed ventillation systems are important.

about 3 months ago
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Gaining On the US: Most Europeans To Be Overweight By 2030

impossiblefork Re:Not the way we have carbs now (329 comments)

But calories in and calories burned aren't independent variables.

You can cause health problems that make eating less impossible by eating less sooner than you would cause healthy weight loss. There's an old story that I found in an old fechtbuch. An english fencing master complained of a spanish argument that you if you always held your point as far towards your opponent as possible would strike him first, and he compared this argument an old story of how a man goes to woman for a cure against seasickness who is to have told him to "Take this rock. As long as you have it in your mouth you will not throw up" and as he went to sea and eventually threw up he realized the precise way in which the woman's statement was true. I feel that your argument involving this accounting inequality has the same character.

about 3 months ago
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Tesla Logged $713 Million In Revenue In Q1 and Built 7,535 Cars

impossiblefork Re: Sponsor? (131 comments)

Computer holography, Path-tracing, the fast-multiple methods for radiosity-- and if it has to be automotive related: alternative thermodynamic cycles for engines, field modulated magnetic couplings (like the ones magnomatics are making as gearboxes/electric drive systems for cars) or mass-production of parts from fibre reinforced plastic.

All of these are nerdier, but perhaps not as easily digested.

about 3 months ago
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Autonomous Car Ethics: If a Crash Is Unavoidable, What Does It Hit?

impossiblefork Re:Screw other people (800 comments)

Then pretty much every human would have no business driving. The way to ensure this is to greatly honor whoever acts correctly and to ensure that there will be more of them. That is of course society's prerogative however and in a bad society where this is not rewarded the cost is paid in lives instead.

about 3 months ago
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Autonomous Car Ethics: If a Crash Is Unavoidable, What Does It Hit?

impossiblefork Re:Screw other people (800 comments)

You don't. You precommit and most respectable people have precommitted to not running over pedestrians and motorcyclists almost from birtth.

about 3 months ago
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Autonomous Car Ethics: If a Crash Is Unavoidable, What Does It Hit?

impossiblefork Re:Screw other people (800 comments)

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.

about 3 months ago
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"Going Up" At 45 Mph: Hitachi To Deliver World's Fastest Elevator

impossiblefork Re:Expensive (109 comments)

Hitachi does have a prototype of just that and it is linked to from the wikipedia page that you linked to. A video showing what seems like a prototype of it is the last linked thing.

It seems like something which would definitely allow higher passenger capacity for a given amount of shaft space.

about 4 months ago
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Michael Bloomberg: You Can't Teach a Coal Miner To Code

impossiblefork Programming is unlikely to be a primary profession (581 comments)

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.

about 4 months ago
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Online Skim Reading Is Taking Over the Human Brain

impossiblefork Re:The world is changing. (224 comments)

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.

about 4 months ago
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Elon Musk Talks Tesla, Apple, Model X

impossiblefork Re: Truly (99 comments)

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.

about 5 months ago
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Elon Musk Talks Tesla, Apple, Model X

impossiblefork Re: Truly (99 comments)

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.

about 6 months ago
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Elon Musk Says Larger Batteries Might Be On the Way

impossiblefork Re:Wake up SAE. Standardize TREs now. (191 comments)

With broken sentence I wanted to express that I believe that 'series hybrids are an established thing that I believe they are the reasonable solution to range problems in electric cars', but as can be seen I failed at this.

about 6 months ago
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Elon Musk Says Larger Batteries Might Be On the Way

impossiblefork Re:Wake up SAE. Standardize TREs now. (191 comments)

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.

about 6 months ago
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Your 60-Hour Work Week Is Not a Badge of Honor

impossiblefork Re:It's a status thing (717 comments)

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.

about 6 months ago
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Your 60-Hour Work Week Is Not a Badge of Honor

impossiblefork Re:Your Boss (717 comments)

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.

about 6 months ago
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Financing College With a Tax On All Graduates

impossiblefork Re:How about no tution at all? (597 comments)

While the Germans have different tracks, we don't here in Sweden and university is free here as well (there are also loans and benefits for living expenses, conditional upon getting a certain number of credits and so on), so it's unlikely that the track system is a necessary part of the German system.

about 6 months ago
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How Silicon Valley CEOs Conspired To Suppress Engineers' Wages

impossiblefork Re:see also, increasing the # of H1Bs awarded (462 comments)

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.

about 7 months ago
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Will Electric Cars and Solar Power Make Gasoline and Utilities Obsolete?

impossiblefork Re:Energy density. (734 comments)

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.

about 7 months ago

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