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Comment: Re:It's almost like the Concord verses the 747 aga (Score 1) 150

by nukenerd (#49158171) Attached to: Hyperloop Testing Starts Next Year

High speed railway .... requires massive earthworks because of the very limited turning radius and limited climb angle of high speed trains.

Obviously you don't know much about railways or dynamics. High speed trains can take much steeper gradiants than lower speed ones, partly because they are so powerful (have to be, for the speed) and partly because their momentum takes them up with little effect on speed (kinetic energy relates to the speed squared). The new lines built for the French TVGs have such gradients, following the natural land contours, that some passengers complain of the up-and-down feeling - like you get with hump bridges on the road. Curve radii are also less of an issue as high speed trains generally tilt into the curve.

A Hyperloop train doing 800mph is going to be very restricted in its vertical and lateral curvatures to limit the centrifugal accelerations (despite tilt) given to the passengers, if they are not going to barf up their last meals.

It requires very specialised rails that have to be laid under very high tension and welded so that the result is seamless and can withstand large temperature variations.

You have just described standard track-laying practice these days. It is not special. Keep up.

It's also much more expensive to ballast because normal ballast doesn't cusion things well above certain speeds and turns into nasty pebbles instead of spikey lumps of rock.

Most high speed track is slab track these days. The effect you describe occurs with track movement and does not occur if the track is properly laid, properly drained, and has modern stock running on it. It is actually more likely to occur on secondary lines with clapped-out rolling stock running on it. Believe me, I am an ex-railway engineer and have had to deal with such trouble-spots on the track .

Whether or not the hyperloop claims are valid, I don't know,

The low costs are fantasy.

Comment: Re:It's almost like the Concord verses the 747 aga (Score 1) 150

by nukenerd (#49158115) Attached to: Hyperloop Testing Starts Next Year

'the Hyperloop is a High Speed Railway"

Nope. Rail is heavy and thus mostly must reside on the ground

There are things called viaducts and tunnels. A lot of modern high speed lines are built with one or the other. Japan's in particular are largely elevated, and much of the UK Channel Tunnel link line through south east England is in tunnel. And if the railway (sorry "non-railway Hyperloop" if you picky about semantics) is not "heavy" it will not be carrying many people, an equivalent to Concorde in the airline world; as such it won't be solving many people's transport problems.

and thus cuts everything in half along its path

There are things called bridges.

Look, you Amercans seem to make very heavy weather of railways "cutting things in half". It seems that for historical reasons, when a railway was built in the USA, the upper classes all settled on one side of the tracks and the lower classes and industry on the other. So the town grew up "cut in half", joined by multiple level crossings which are forever a source of frustration and delay. I have a picture in my mind of the train rolling through a city on a dead-straight track at ground level at the end of "Back to the Future Part III" - such a scene is essentially American and I cannot think of a layout like that in the UK. In Europe railways fit in much more comfortably. In the UK you are practically unaware of the existence of railways (many people are) unless you use them. Even farm tracks have their own private bridges or underpasses. In the centre of Birmingham for example you can be totally unaware that there is the biggest station UK outside London beneath and around you, and most of it is not even underground.

and hampers if not stops any traffic along its path.

Along its path ?? I don't get it.

Comment: Re:It's almost like the Concord verses the 747 aga (Score 1) 150

by nukenerd (#49158025) Attached to: Hyperloop Testing Starts Next Year

Sure, because the cost of materials has little to do with the cost of building a highspeed railway. You've got a mighty wide right of way, and you need to buy a huge amount of land for that, plus there's a ton of labour to prepare that right of way, clearing it of all obstacles, leveling the terrain, installing the track, the filler, etc.

Well, I don't know about the USA, but in the UK there is no way that you could put a tube on stilts above some-one's land (let alone buildings) without buying it off them, or paying a significant rental for the wayleave, as it is called. Even the latter would only be acceptable if the land use was not residential.

Again in the UK, when railways were first built, in cities a lot of them were built on arched viaducts (in South London particularly) so that the arches could be rented as workshops and warehouses. Or the railways were built underground. The same thing with motorways 100 years later, but even so houses under motorway viaducts generally have to be bought and demolished (not least because such houses would be unsellable otherwise). These approaches are so expensive however that as soon as railways or motorways get clear of the city they get back to ground level. That is even in the cramped UK; I thought that OTOH, except in cities, the USA was wide open spaces. Why put a tube on stilts above a desert or wilderness, unless over a gully?

Comment: Re:It's almost like the Concord verses the 747 aga (Score 1) 150

by nukenerd (#49154363) Attached to: Hyperloop Testing Starts Next Year

unlike airplanes, high speed rail and traditional tube is that in the concept you'll have... 18-24 passengers/train, which hopefully means you can have many more dedicated routes and/or a mix of long-hop/short-hop routes using the same infrastructure that'll serve the whole 3000 miles and not just the endpoints. ........It's a lot easier to find 20 passengers going somewhere at the same time than 400-800 so that could be a major game changer if the technology works out.

But then you will need to wait around until 19 other passengers turn up who want to make the same journey as yourself. Also, running trains of such low capacity severely limits the total capacity of the line (and hence the payback) because the trains must be kept a minimum distance from each other (at least the braking distance).

Trouble with mixing long-hop and short-hop on rail (we call them main-and-local or fast-and-slow in the UK) is that the local train stopping holds up the "fast" train behind, so in the end they all might as well stop at all stations. That is what metro lines generally do. Another approach is to have stopping loops at each station so that the fast train can overtake the local, but that can lead to long waits for the local before leaving stations (think about it). British Railways decided to abolish most intermediate stations and local trains on non-suburban lines in the 1960's.

The best solution is to have multiple pairs of tracks for different types of train. There are basically six tracks (ie three pairs) from Euston (the main London terminus for the North-West) for the first 16 miles though the suburbs, and then reducing to four.

Comment: Re:It's almost like the Concord verses the 747 aga (Score 4, Funny) 150

by nukenerd (#49154175) Attached to: Hyperloop Testing Starts Next Year

I the cost of California High-Speed Rail, it's actually $68.4 billion for a the things as of 2011 estimate

As far as I can make out, the Hyperloop is a High Speed Railway inside a tube that structurally can take a vacuum. Plus things like airlocks to get in and out, and some very clever safety measures to allow people to escape in an emergency.

Yes, that has got to be cheaper than just a High Speed Railway, hasn't it?

Comment: Re:file transfer (Score 1) 446

by nukenerd (#49145475) Attached to: Ask Slashdot: Old PC File Transfer Problem

he can't use floppies to transfer the data from the Aero to a computer using a USB floppy drive because they have problems reading each other's disks. This is not uncommon when dealing with the older floppy disk technologies.

I don't understand that. I used floppies for many years, and occasionally still do to retrieve old data, and very rarely had a problem. Also, a USB floppy drive is not "old technology" - the original floppy drives were all IDE.

I recently had a campaign of getting any useful data off my collection of 3.25" floppies. I must have looked through about a hundred of them (I have hundreds more) and only one had failed; they had kept data for about 20 years. I even installed WordPerfect off floppies (new in 1991) in order to read some of the old documents.

I believe that the problem arose with later floppies made, which were crap. Earlier ones made by IBM or 3M (which I had used) were fine until the Chinese undercut their prices. The Chinese ones (usually identified by bright colours and lack of branding) are the trouble.

Comment: Re:file transfer (Score 1) 446

by nukenerd (#49145439) Attached to: Ask Slashdot: Old PC File Transfer Problem

This. Is why I don't throw my old gear just because some PHB says it's "obsolete". It's obsolete when smoke pours out of it and I can't get the fucking fans to spin.

Same here. I have under my desk a Pentium III in a tower, with parallel, serial, USB, Ethernet, floppy, CD, DVD and a multi-boot set up of DOS, Win98, Win XP and Debian. I fired it up last week to run WordPerfect to retrieve some old documents from floppies.

I think it was a couple of weeks ago that there was a warning that, looking back from the future, the present time will appear to be a digital dark age, with photos and documents lost in this way. Of course, some people don't give a toss.

Comment: Battle of Bolimów (Score 1) 224

by nukenerd (#49115993) Attached to: 100 Years of Chemical Weapons
The first significant use of gas was by the Germans against the Russans at the Battle of Bolimów in January 1915. Hardly anybody has heard about it, being on the Eastern Front. The Germans chose this for the first use of gas because it was less "public" than the Westen Front; also the prevailing wind in Europe being from the west. On the Western Front the Germans were always at a disadvantage with the wind.

Comment: Re:simple (Score 1) 286

by nukenerd (#49115865) Attached to: An Evidence-Based Approach To Online Dating

You will get x% of response rate. y% of conversations will turn into first dates. z% of first dates will turn into something more. Sure, you can tune the x, y and z values, and if they're really low you should. But once you're out of the single digits, raising the amount of input will result in more gain in output than tuning those numbers.

I can put some figures to that. I got about a 5% response rate to my first contact; 2.5% (ie half the previous) response to follow-up message (my proposing a meeting); met 2% face-to-face; had second date with 1%; met regularly afterwards with 0.5%; had sex with 0.3%; married 0.1%.

Bear in mind that I only contacted ones in the first place if their profiles seemed well matched to me (eg I didn't contact ones who demanded men over 6ft or had tattoos, because I didn't). So imagine if I had approached girls at random (like at a dance) - you could divide those figures by 5 or 10 again. And I am well off and not bad looking.

Comment: Re:Or... (Score 1) 286

by nukenerd (#49115705) Attached to: An Evidence-Based Approach To Online Dating

...you could just ask someone out that you meet in person, thus avoiding all of this investment of time and effort before you even know that there's going to be a basic mutual attraction. You're going to have to interact face-to-face eventually anyway.

Care to offer any advice how to meet this "someone" in person? Because I never found out. Almost the only girls I saw around when I was of potentially courting age were ones that happened to be walking past in the street. The very few social occasions at which any girls were present they were outnumbered by men at least 5:1, and in a room of 25 men and 5 girls there were bound to be at least 5 men more charming than me (usually the married ones in fact as they were used to dealing with women). I did try to start a conversation a few times but was told to fuck off, or words to that effect. Never bothered again, I kept to dating clubs (this was before the Internet).

You could invest a lot of time and effort joining like art or poetry clubs in the hope of meeting girls (they don't join model engineering clubs in my experience) only to find that any you find there are already-married/have-a-boyfriend-already/not-interested/joined-only-because-they-actually-like-art-or-poetry/ugly/lesbian/ten-years-older-than-you/6ft-tall/dont-like-you-anyway. All that shit can be cut out by joining a dating organisation.

Of course you are going to have to interact face-to-face eventually; that's the point. Online-dating critics for some reason seem to think that they are about relationships that are confined to being online. That game exists too, but it is a differnt game; don't confuse them.

Comment: Re:The title is misleading (Score 1) 81

Referring to the article: When a modern city doubles its population, it grows 83% in size (ther than 100%); this seems to hold true for ancient cities.

I don't know what they mean by modern, but that is certainly not true for British cities over the last 200 years - which is modern times as opposed to ancient times. Back in the early 1800's people lived very close together; merchants lived over their shops and the poor lived in slum apartments. The very wealthy lived elsewhere - in country mansions.

Then as the population increased with more people moving in from the countryside (which was getting mechanised) and immigration, the middle class moved out to get away from the increasingly crowded and unsavoury centre into new suburbs, where each house had a garden. Far more land was taken up per person there. This process is continuing today, with ever-expanding urban sprawl.

Comment: Re:Boring (Score 1) 286

by nukenerd (#49110915) Attached to: An Evidence-Based Approach To Online Dating

5). Make some friends in IRL. A friend will know someone else who is single.

Haven't you been reading these comments? How?? FFS. Personally, I have never "met" any girl IRL, by which I mean having a social conversation lasting more than about 20 seconds, the conversation usually being terminated by her walking away or being interrupted by some other guy and her turning her back on me. Yet I an not ugly or fat, if that is what you are thinking. God knows how guys get on who are.

I met around 100 girls through dating clubs (a bit before the Internet) and it is only by girls being in a "captive" situation that some seemd to find they actually liked me. About 1 in 5 led to second dates, and 1 in 20 became longer affairs - but bear in mind we had already been through a selection process of exchanging letters and photos. If we assume that of people chosen at random only 1 in 3 would pass that preliminary selection process, and that must be squared because the selection is both ways, it means that I would have needed to approach ~200 girls IRL to get as far as regular dating; and even that assumes that they had not got a boyfriend already. That would have been impractical; I would have needed to have collared them in the street, and I'd have been arrested for molesting. If it had not been for dating clubs I think I would have settled for seeing escorts; looking back, perhaps that is what I should have done anyway -I could afford it, and some of them are suprisingly nice, much better than many IRL girls.

As for friends knowing someone else who is single, I have always had friends of the same sex, but none has ever introduce me to a girl - why would they? Usually, they haven't been able to find girlfriends themselves, and they weren't poor and ugly either. Something has gone wrong in our society.

Comment: Re:My tips (Score 1) 286

by nukenerd (#49110731) Attached to: An Evidence-Based Approach To Online Dating

Some women do seem very interested, but I'm just not interested in them as they look like the NASCAR fans

I think you should be more charitable; you sound a bit snobbish. They say women like intelligent men, but that's rubbish. What they like is "entertainers". I am bright, but never found it an advantage at all. Women of similar intelligence, or a league or two down, seem to resent it. I deliberately act less intelligent when I am with women.

But in my courting days I got on best of all with really dumb girls. They would not at first even realise that I was particularly intelligent, because to them, everyone else was more intelligent anyway. They just floated through life best they could. The type of girl I am talking about, the type I liked best, were demure, sweet, pretty, submissive (ie. they would let me choose where to go and what to do, and were happy), did not start arguments.

Best of all, they would do girly things like cooking and sewing and leave me to do the things like mending cars. They also tend to be more attractive, because that was their main strength - they were never frumpy. This is all very non-PC of course.

As for their liking NASCAR, the girls I am talking about tended to like what some previous boyfriend had shown them to like. They would soon adapt to anything else though, like standing on the side of a football pitch, or sitting in a classical concert if that's your thing.

Money may buy friendship but money cannot buy love.