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quantumstate

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"If you need heat, it's much more fuel efficient to just burn fuel and not bother turning it into electricity in an intermediate step."

This isn't always true. Carnot's Theorem works in reverse as well, so you can use a heat pump (like an air con unit) so get more heat out of your electricity than just dumping it into a coil. This is actually practical and is being done today for heating houses, you can easily beat the other inefficiencies because the temperature difference that you are trying to create for your house is much smaller than the one between the gas furnace and the ambient temperature around the power station.

For heating a pan though I think this is unlikely to be practical any time soon.

It is hard to use clear terminology without getting very technical. The basic idea is that a gas power station has a limited efficiency, I think about 55% of the chemical energy in the gas becomes electrical energy. This is due to a mixture of engineering limitations and fundamental thermodynamic limits of a heat engine (http://en.wikipedia.org/wiki/Heat_engine#Efficiency).

So for gas hobs to beat induction hobs, if we assume 100% efficiency for an induction hob (electrical energy to heat energy in the food), the pan needs to get >55% of the chemical energy from the gas into the food.

I don't have any figures but it isn't infeasible that a gas hob could be more efficient.

I am from the UK and here it is 28 days minimum holiday [1]. I believe it is fairly common to have the 8 days bank holiday as fixed days and then 20 days chosen by the employee initially. After working at a company for a period in increase in the holiday allowance would be expected. After one year at my work I am on 25 + 8 days, there is flexibility to work on some of the bank holidays, taking the holiday at a different time, as long as the office will be open (pretty much every time apart from Christmas).

[1] https://www.gov.uk/holiday-entitlement-rights

I'm not sure I would call the system more sophisticated than AoE, it is very similar. There are three phases; Village, Town and City which work similarly to the AoE series, unlocking units, buildings and technologies. The idea behind only having three is that the first age in AoE tended to be quite limited so in 0 A.D. the aim is to make the village phase more significant with it being more like the second age in AoE2/AoM in terms of available units.

No, the game is set in the period from 500 B.C. to 1 B.C. and during that period firing while moving was not common. It could possibly be added for some types of high quality horse archers but isn't a high priority.

To clarify, there has been support for multiplayer games for a long time. Currently you connect to other players by entering the host player's ip address.

What is currently being worked on is a lobby system so you can create an account and view listings of what games are being hosted. The work is probably going to be added to the game soon, then further improvements like a ranking system can be added in the future.

I work on a large piece of C++ software (millions of lines) and unfortunately this feature does not work well enough to be worth using. The first problem is that it takes far too long, much longer than the rename method and waiting to recompile. The other pretty serious problem is that it sometimes misses references so I just can't trust it.

As an extreme counter example I visited rural South Sudan, this is one of the poorest parts of the world, people are subsistence farming so their monetary income is very low. Some people struggle to pay school fees of 20 South Sudanese Pounds ($6.88) a term (3 terms a year).

Government funding is pretty limited so a lot of schools are supported by the church there, I think the funds are mainly provided by Christian organisations outside of the country.

My theory is that people with a better education are more keen on education. In South Sudan the people in church leadership are highly educated compared with the average person.

Why are you comparing based on size? Surely it is sensible to try and compare economically similar. Western and Northern Europe is probably the best comparison, with a combined population of something like 280 Million, not too far from the US. The murder rates are 1.0 and 1.5 respectively, far lower than the US. The whole of Europe includes Eastern Europe which is much less similar to the US and has a higher murder rate.

Your Wikipedia link shows that the US murder rate is 4.8, the rates for Western, Southern and Northern Europe are 1.0, 1.4 and 1.5 respectively. Eastern Europe has a higher rate of 6.4. If you are looking at economic similarity Western, Northern and some of Southern Europe are comparable to the US. So the murder rates are very different.

I was recently in rural South Sudan, at a place where there are no power lines within 80 miles. So the systems they use must be off the grid by necessity.

There were several PV and battery setups there which worked pretty well. Obviously you need to be careful with the amount of power that you use, but it can run computers, TV and lighting with a reasonable setup.

There was a computer lab at one installation which had one desktop machine acting as a server and about 15 thin clients to keep the power usage low.

Higher pixel counts give less noise assuming the total light collection area is the same. Normally you get a bit less light collection area due to the gaps between pixels with a higher resolution sensor but overall I think higher pixel count generally wins, especially when working at the low iso end. So as long as the cost is reasonable why not stick lots of pixels in.

Trying to look at how software performance has improved in the way you are looking at it doesn't really work. There is no point putting time into optimising things that run fast enough. There are many algorithms that have been improved dramatically. People use this kind of matching for DNA, nobody is busy creating slower algorithms, they are only getting faster (e.g. www-igm.univ-mlv.fr/~lecroq/articles/cpm2009fl.pdf). Prime factorisation, optimisation, etc. are all being actively researched.

In other areas people are doing things which weren't even possible on old hardware, think about 3D graphics. Real time lighting approximations are doing really clever stuff, just look at the latest unreal engine demo. If you put these into old hardware you would get the same quality render in less time. Modern ray tracing engines are using more sophisticated algorithms, giving better results in less time.

Beyond the algorithmic work optimising for modern hardware is different to old hardware. An optimal program for old hardware isn't optimal for modern hardware and vice versa. Now if a program needs data from RAM you have to wait hundreds to cpu cycles. Even accessing the L3 cache, which is in a modern processor chip, takes about 75 cycles on modern chips. So you can recalculate things and find your program runs faster.

Similar things happen with branches, I was looking at some GPU shaders recently and there was a simple raytracing loop (parallax occlusion mapping), the obvious way to do it is to stop when you intersect the surface. Instead it is actually faster to always run the loop for 10 steps because this removes the branch. So you do twice as many loop iterations on average but your code runs faster.

Of course you can afford to be sloppy as well. People are 'sloppy' so that their code is faster to write, easier to read and less likely to have bugs (3 lines of python is pretty likely to be easy to read and bug free). I would say software is advancing in many different ways, which hardware has enabled to happen.

It someone is feeling faint it is standard practice to lower their head to increase blood flow to the brain. Presumably her husband knew this. I felt faint after donating blood recently (I have low blood pressure) and they have a standard piece of foam to lift your legs up while lying on a bed.

It depends what your company does. Where I work we write CAD/CAM software which gets released roughly twice a year. It is pretty inconceivable that a 3AM fix would be necessary. Even 0 day security flaws in the software (pretty unlikely since there isn't any need for network connectivity) really shouldn't be fixed at 3 am, they can wait 12 hours and be handled under less stress and tiredness.

I think that since a company is deciding on the structure of the interview day they have a responsibility to be transparent about the process beforehand. This is a different situation to the person being interviewed.

For my current company the invitation to the interview says that if they like you then you will be invited to continue to another stage of the interview after lunch (they deliberate/discuss while you have lunch).

I'm surprised that you got that impression. I'm from the UK, I have visited the US once and was in the Philadelphia suburbs. I would say that the UK has smaller homes and gardens. In the UK most people live in dense cities and towns as opposed to suburban sprawl in the US, this limits space available.

I would agree that in England we spend more time gardening (though "most of their 'home' time" would be an exaggeration, possibly true in summer). There is strong separation of gardens in the UK as well, not having a fence would be very unusual, whereas where I was in the US back and front yards weren't clearly delineated.

I Google everything 14 years ago

I'm actually pretty surprised about the curry thing. Here in the UK we get so much US media (films and TV) that I feel like I have a fairly good grasp of what they have in America. Not having curry has shocked me though.

Basically you cam imagine a market with only long term traders, there is a certain amount of money being generated by companies which feeds the profits of the market.

Now add some HFTs, these make a profit (there is empirical evidence for this claim). Now money is leaving the market without going to long term investors. Thus the long term investors are making less profit.

Now the big unsubstantiated assumption I have used above is that HFT adds no value to the market. I do not feel I am in any position to argue about whether this assumption is good or not. The above argument is presented in the hope that it makes things clearer and points towards what I think is the fundamental point which needs to be discussed: "Do HFT traders add value of a market?"

I work for what would probably be classed as a BigCorp. As a developer I get to spend my days programming. There are departments which handle all of the marketing, customer support, ... By the time tickets reach developers most information for debugging has been handled by the intermediate layers (occasionally you find it is inadequate of course).

The structure a large companies provides can, if done well, handle the things that get in the way and let you get on with developing. Of course you generally get a prescribed set of tasks so you don't have much flexibility with what you need to get done.

I have spent the last two years at university cycling to lecture and am now cycling to work. It saves a large amount of money (~£1800 insurance+£1500 running costs). If it rains you just wear waterproof clothing. You can easily get good quality waterproofs (e.g. Gore-Tex) for £200 which will last for years.

You have to be willing to live fairly near to work of course. For me it would probably take about the same amount of time to drive to work. It takes me about 13 minutes to cycle and rush hour traffic will slow a car down.

If I want to go longer distances I can catch a train (and take the bike for the other end) or take a bus. Occasionally hiring a car is also possible for rare occasions.

So for me using a bike is completely feasible for living in a city.

This is exactly the way the courses at my University (Cambridge, UK) worked. The lectures covered all relevant course material and problem sheets were given out (also available online http://www.damtp.cam.ac.uk/user/examples/).

Each course had a short list of recommended books and usually the lecturer would give a few comments about each book at the start of the course. These were for supplementary reference and were widely available in the libraries. I bought one text book during my course for my favourite area, so I could keep it after University. Otherwise the libraries were completely adequate.

I studied maths, I know that computer science and physics were the same. With arts subjects students used so many books that it wouldn't be reasonable to by them. I am not aware of any courses having required textbooks but I don't know for certain.

The specific heat is the energy needed to raise the temperature per mass. So for water it takes 4.184 joules per gram to raise the temperature by 1 kelvin. So if you heated water to 75 degrees you would have put in about 205 joules per gram. You then have to deal with conductive losses and the efficiency of a heat engine.

This is not directly comparable to the energy density of gasoline or a lithium ion battery which use chemical reactions to store the energy. So you can turn almost 100% of the energy in a lithium ion battery into useful work but if you put the equivalent number of joules into heating an object you wouldn't get close unless you have a handy 0 kelvin object.