Really? I've had a 1st Gen IPod Touch in daily use for three years now. There is not noticable degradation of battery life. Not saying there isn't any (I'm sure there must be), but nothing that you would notice. And if the battery does die, it's easy enough to get it replaced.
The beauty of a swiss army knife is that it can be always to hand (or in pocket). I could carry around a set of screwdrivers, knives, scissors, tweezers, toothpick, biro, bottle opener, allen keys and torx wrench. I could wear a pair of trousers with pockets large enough to accomodate all of these tools.
Then normal people would no doubt cross the road to avoid me!
Why bother with a Gearbox? It should not be needed with an electric motor.
I recall that Tesla started off with a 2-speed gearbox. They abandoned it when they found that it was unnecessary and just added complexity and weight.
Let's see - assume a tank of gas last 200 miles (low, but lets aim at the US - gas guzzler market here, not a super-efficient euro-diesel that does 1K miles per tank)
200 miles x 6000 tank-fulls = 1.2 million miles. That's a pretty high mileage vehicle. I think more than the fuel tank might need replacement.
Also the batteries don't drop dead at 6000 cycles. They might only take 80% of their original capacity.
Assume a charge only lasts 100 miles (pessimistic) you are still looking at 600k miles of driving. If you do 10k miles a year then that is 60 years, so the batteries are likely to outlast the driver!
I can just imagine the conversation inside Jobfinger's secret lair in the hollow volcano just outside Cupertino........we never thought you idea of planting a dummy iPhone prototype in a coffee bar would work, but what do you know - they fell for it!
Try Contacting www.digimap.gg. They have a lot of experience with scanning old maps and warping them to fit current mapping. They also have a (very) large format high quality scanner which should cope with any map that you have.
Talk to them nicely and they maybe able to help you at a very reasonable price. However they are located in Guernsey, which may not be convenient for you.
Do microsoft still have the section in the Visual Studio License agreement that says you aren't allowed to develop anything (with VS) that competes with Microsoft Office?
I think it's interesting that the whole electric vehicle debate has shifted in the last year away from the issue of how to store a reasonable amount of power in a vehicle.
What I hear now is "but it takes 8/12/x hours to recharge!".
This issue does not seem to be down to the battery technology available today, rather it is due the fact that you simply cannot pull enough power out of a standard domestic circuit to recharge these vehicles in a reasonable time.
This isn't hard to see: If you have a 50KWh power pack in your vehicle and you want to charge it in 6 minutes then you need a 1/2 Megawatt supply. A standard 50Amp/240 V supply will deliver about 12KW (or 0.012MW). Go figure.
Megawatt rated power supplies are not rocket science (most electric trains operate at this level) However the cost of installing such a supply at home is likely to be prohibitive for most users (especially if you only need it for a few minutes a week).
I predict that we will shortly see the rise of the "electric filling station" equipped with the kind of power infrastructure that can be optimised to deliver Megawatt-level loads into electric cars.
We just need to deal with the minor issue of designing a domestic power supply that can deliver the 50-100KWh needed to charge such a vehicle within 5 minutes. How do you deliver power at half megawatt rates over domestic wiring? (That's 5000A at 110V for you guys over in the States)....
If you actually read the article, this seems to be exactly what they did do. The "driving round for a few few months" only happened after they had both tested it on an engine in a test rig and then on a car similarly rigged up on a test rig.
I think the biggest reason for higher fuel efficiency in Europe is that fuel there has been more highly taxed for many years.
What do you pay in the US for petrol today - $4 a gallon? That translates into about GBP0.58p per litre at current exchange rates. The UK hasn't seen petrol prices that low for ten years. Current prices are nearer GBP1.11(petrol) - GBP1.25 (diesel) per litre. In US terms that is petrol at £7.50 a US gallon.
If you paid that much or fuel, you would care a lot more about fuel efficiency.
Ultimately Europeans are no greener than Americans - we are just being given more encouragement to be green by Adam Smith's "invisible hand".
Why do you want to have a computer that you have to boot from cold?
My MacBook wakes from sleep in a couple of seconds. A couple more to log in. It will stay in sleep for days on a fully charged battery.
When I do reboot, I'm pretty sure that MaxOS X comes up to usable in less than 60s (not that I have timed it) Of course I probably reboot less than once a week anyway.
There seems to be a lot of misunderstanding about how a fridge based on these materials would work. Compare it with existing refrigeration systems: -
1) Compressor based systems. Here a working fluid (freon, etc) is pumped around a sealed circuit. At one point in this circuit it undergoes a state change (i.e. is compressed) and releases heat to the environment (via the radiator on the back of your fridge). At another point in the circuit it undergoes a different state change (i.e. pressure drop) and it's temperature drops as a result (taking in heat from the environment). Note that this is a working fluid we are talking about here.
2) Thermoelectic devices. These rely on devices with the property that when a voltage is applied to them a temperature gradient is created directly. Quite elegant, but not very efficient with currently available materials (although there have been recent developments in this area which may make them as efficient as compressor based systems in the medium term).
3) Polarpolymer based devices. In this case the working material is a solid with the property that when you apply a voltage it undergoes a state change causing its temperature to rise by 22degrees. The heat released would then have to be removed to the environment (for example by blowing air over it and venting this to the environment). When the voltage is subsequently removed, the material returns to its original state (22 degrees F colder). You would then need to circulate air from the inside of your refrigerator over this material. Some of the heat in the (inside) air would transfer to this material, warming it up. A drop of more than 22 deg could be created by daisy-chaining several devices together in series to create an arbitrarily large drop.
So a polarpolymer based refrigerator would probably require a quite different design to a traditional fridge because the working material is a solid rather than a fluid, and it does not directly create a temperature gradient across the material.
It probably wouldn't be suitable for small scale applications such as gloves, or for cooling clothing - unless your application just wants a one-time temperature rise/drop and the reverse step takes place away from the wearer of the clothing.
Easy solution is to run a standard phone line down the length of the dirt track, attach a suitable ADSL router/bridge at either end and you are on the net.
Seriously, I did this 7 or 8 years ago to an outlying building where we had our office at the time. It worked a charm over existing standard telephone wiring. 8MB with no problems.
At the time the two DSL bridges probably cost $1000. They probably give them away today,
Actually they have offshore windmills all wrong - they should be putting the spinning bits Under the water to take advantage of the tidal currents around the UK, these have a number of advantages: -
1) There's much more energy density in all that dense water that's moving around (even if it doesn't move as quickly as the wind)
2) Most importantly, tidal currents are very, very predictable (unlike the wind). You can easily work out years ahead exactly how much energy you are going to be getting from each tidal turbine.
3) Although any tidal turbine is going to experience times of slack water, the nature of tides is such that given a sufficient geographic spread, this will happen at different times in different places.
4) Tidal turbines are effectively invisible - the business end is entirely underwater. (Although there are, of course, questions about the effect of spinning blades on fish, and the problems of fishing boats.) Compare that to a 1000ft high windmill.
Some estimates put the amount of energy available around the Channel Islands (off the northwest coast of France) at anything up to 25GW - which is hardly surprising given a local tidal range of 10-12m.
Other areas around the UK (such as the Bristol Channel) have an equally high potential.
Why aren't we putting more effort into developing what seems to be the ultimate renewable energy resource - reliable, predictable, and with minimal impact on the environment?
Down time should not be an issue with a well maintained server system. I've had experience with systems on these lines that had uptimes measured in years. (They were running UNIX or VMS in those days of course, not Windows.).
If you are worrying about the time you would loose on the very rare occasion that a server goes down - ask yourself how much time you waste wating for your desktop PC to startup/shutdown?
Personally I can recall the days of the VT220 terminal. Boot time was a couple of seconds. I could come into work, turn it on, log in and start working immediately. Even sharing the same server with 20 other developers, it seemed faster to me.
Today I come into work, turn on the PC and then go and make a cup of tea. If I'm lucky it's ready to log in by the time I've done that. Then it's time to make another cup of tea while Windows churns through whatever it does when I first log in (i.e. running all the anti-virus/spyware that cripples my computer for the first five minutes of the day).
It's probably not an exageration to say that I loose ten minutes every day to this sort of activity.
I could also talk about the problems of trying to shut down Windows. Who hasn't tried to shut it down, turned the monitor off, gone home and come back the next day to find a message saying "Application XXXX didn't want to stop. Do you want to terminate it?" So you then have to wait even longer for W£$%£$$%s to shutdown and start up again.
I could of course leave my computer on overnight, but that only works till the oil runs out or rising sea levels drown my office!
I don't think the recharge issue is at all insurmountable.
Look at electic trains - the TGV in Europe has a continuous rating of 3-8MW. They have been running quite happily for well over 20 years.
In that light drawing 1-2MW at a filling station for 5 minutes doesn't seem particularly challenging.
There are a number of ways aoround the problems that have been raised here: -
Use a higher voltage. Railways typically use overhead wires at 25KV. At that voltage 1MW is a very reasonable 40 Amps.
Filling stations have their own local banks of Ultracapacitors which are used to store energy before it is used to fill vehicles. This evens out the demand on the grid. If they fill 1000 cars at 100KWhr per day, that is 100MWH, or an average draw of about 4MW. That seems very much in line with the sort of power an electric train might draw.
While 25KV and 1000's of Amps might seem scary for anyone used to a domestic supply, I doubt that anyone accustomed to using these in industrial applications would bat an eyelid. I doubt there is any new technology that needs to be developed in this area to make it a reality - possibly some production engineering to make it more cost effective, but no show-stoppers.
We use Leica DGPS equipment with our own DGPS base station. Accuracy depends on how far you are from the base station, but on our fairly small island we reckon on 1-2 cm accuracy, horizontally and vertically. This does depend on having sufficient satellites in view - this is a problem under trees and close to buildings and steep slopes.
I don't think that cable length is the main problem. A geostationary (lunostationary?) orbit around the moon is only about twice the radius of a similar orbit around.
By my calculations it should be quite possible to build a space elevator to the lunar surface with a tether made of Kevlar. Such a cable would only require a taper of around 1.7, which seems quite reasonable.
Of course there's the problem of getting a few thousand tons of kevlar up there in the first place...
It seems to me that the problems of building a Space Elevator would be significantly reduced if be built one from the lunar surface. With one-sixth of the gravity of the earth, would it be practical to build a space elevator to the lunar surface with currently available materials?
Might this not be a useful exercise to demonstrate the feasibility of the "Space Elevator" concept, while also giving us relatively easy access to the lunar surface?
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Really?
I've had a 1st Gen IPod Touch in daily use for three years now. There is not noticable degradation of battery life.
Not saying there isn't any (I'm sure there must be), but nothing that you would notice.
And if the battery does die, it's easy enough to get it replaced.
The beauty of a swiss army knife is that it can be always to hand (or in pocket). I could carry around a set of screwdrivers, knives, scissors, tweezers, toothpick, biro, bottle opener, allen keys and torx wrench. I could wear a pair of trousers with pockets large enough to accomodate all of these tools.
Then normal people would no doubt cross the road to avoid me!
Why bother with a Gearbox? It should not be needed with an electric motor.
I recall that Tesla started off with a 2-speed gearbox. They abandoned it when they found that it was unnecessary and just added complexity and weight.
Let's see - assume a tank of gas last 200 miles (low, but lets aim at the US - gas guzzler market here, not a super-efficient euro-diesel that does 1K miles per tank)
200 miles x 6000 tank-fulls = 1.2 million miles. That's a pretty high mileage vehicle. I think more than the fuel tank might need replacement.
Also the batteries don't drop dead at 6000 cycles. They might only take 80% of their original capacity.
Assume a charge only lasts 100 miles (pessimistic) you are still looking at 600k miles of driving. If you do 10k miles a year then that is 60 years, so the batteries are likely to outlast the driver!
- Car fuel that only needs to be refilled monthly?
I already have one of these (and probably nearer every two months). Of course it helps that I don't drive much and cycle to work ;-o
I can just imagine the conversation inside Jobfinger's secret lair in the hollow volcano just outside Cupertino.... ....we never thought you idea of planting a dummy iPhone prototype in a coffee bar would work, but what do you know - they fell for it!
Try Contacting www.digimap.gg. They have a lot of experience with scanning old maps and warping them to fit current mapping. They also have a (very) large format high quality scanner which should cope with any map that you have.
Talk to them nicely and they maybe able to help you at a very reasonable price. However they are located in Guernsey, which may not be convenient for you.
I knew it - those headaches are being caused by all the damn Mozart on my iPod.
I'll get rid of it right away (not to mention the Chopin, Beethoven, Debussy and Schubert...)
I expect Accountants get tired of it too (Wait! You mean the girl who looks after the petty cash isn't interchangeable with the CFO?)
Hmmm... I ran my first VM under Windows NT 4.0 with a Pentium and 32MB of RAM. (About 10 years ago with Version 1 of VMWare.)
Not sure it it would have run Windows 7 though!
Do microsoft still have the section in the Visual Studio License agreement that says you aren't allowed to develop anything (with VS) that competes with Microsoft Office?
I think it's interesting that the whole electric vehicle debate has shifted in the last year away from the issue of how to store a reasonable amount of power in a vehicle.
What I hear now is "but it takes 8/12/x hours to recharge!".
This issue does not seem to be down to the battery technology available today, rather it is due the fact that you simply cannot pull enough power out of a standard domestic circuit to recharge these vehicles in a reasonable time.
This isn't hard to see: If you have a 50KWh power pack in your vehicle and you want to charge it in 6 minutes then you need a 1/2 Megawatt supply. A standard 50Amp/240 V supply will deliver about 12KW (or 0.012MW). Go figure.
Megawatt rated power supplies are not rocket science (most electric trains operate at this level) However the cost of installing such a supply at home is likely to be prohibitive for most users (especially if you only need it for a few minutes a week).
I predict that we will shortly see the rise of the "electric filling station" equipped with the kind of power infrastructure that can be optimised to deliver Megawatt-level loads into electric cars.
We just need to deal with the minor issue of designing a domestic power supply that can deliver the 50-100KWh needed to charge such a vehicle within 5 minutes. How do you deliver power at half megawatt rates over domestic wiring? (That's 5000A at 110V for you guys over in the States)....
If you actually read the article, this seems to be exactly what they did do. The "driving round for a few few months" only happened after they had both tested it on an engine in a test rig and then on a car similarly rigged up on a test rig.
I think the biggest reason for higher fuel efficiency in Europe is that fuel there has been more highly taxed for many years.
What do you pay in the US for petrol today - $4 a gallon? That translates into about GBP0.58p per litre at current exchange rates. The UK hasn't seen petrol prices that low for ten years. Current prices are nearer GBP1.11(petrol) - GBP1.25 (diesel) per litre. In US terms that is petrol at £7.50 a US gallon.
If you paid that much or fuel, you would care a lot more about fuel efficiency.
Ultimately Europeans are no greener than Americans - we are just being given more encouragement to be green by Adam Smith's "invisible hand".
Why do you want to have a computer that you have to boot from cold?
My MacBook wakes from sleep in a couple of seconds. A couple more to log in. It will stay in sleep for days on a fully charged battery.
When I do reboot, I'm pretty sure that MaxOS X comes up to usable in less than 60s (not that I have timed it) Of course I probably reboot less than once a week anyway.
Why is this news? I had a hire car (a VW Golf TDI) for a week this summer. I didn't have to try very hard at all to get over 60mpg.
There seems to be a lot of misunderstanding about how a fridge based on these materials would work. Compare it with existing refrigeration systems: -
1) Compressor based systems. Here a working fluid (freon, etc) is pumped around a sealed circuit. At one point in this circuit it undergoes a state change (i.e. is compressed) and releases heat to the environment (via the radiator on the back of your fridge). At another point in the circuit it undergoes a different state change (i.e. pressure drop) and it's temperature drops as a result (taking in heat from the environment). Note that this is a working fluid we are talking about here.
2) Thermoelectic devices. These rely on devices with the property that when a voltage is applied to them a temperature gradient is created directly. Quite elegant, but not very efficient with currently available materials (although there have been recent developments in this area which may make them as efficient as compressor based systems in the medium term).
3) Polarpolymer based devices. In this case the working material is a solid with the property that when you apply a voltage it undergoes a state change causing its temperature to rise by 22degrees. The heat released would then have to be removed to the environment (for example by blowing air over it and venting this to the environment). When the voltage is subsequently removed, the material returns to its original state (22 degrees F colder). You would then need to circulate air from the inside of your refrigerator over this material. Some of the heat in the (inside) air would transfer to this material, warming it up. A drop of more than 22 deg could be created by daisy-chaining several devices together in series to create an arbitrarily large drop.
So a polarpolymer based refrigerator would probably require a quite different design to a traditional fridge because the working material is a solid rather than a fluid, and it does not directly create a temperature gradient across the material.
It probably wouldn't be suitable for small scale applications such as gloves, or for cooling clothing - unless your application just wants a one-time temperature rise/drop and the reverse step takes place away from the wearer of the clothing.
Easy solution is to run a standard phone line down the length of the dirt track, attach a suitable ADSL router/bridge at either end and you are on the net.
Seriously, I did this 7 or 8 years ago to an outlying building where we had our office at the time. It worked a charm over existing standard telephone wiring. 8MB with no problems.
At the time the two DSL bridges probably cost $1000. They probably give them away today,
Actually they have offshore windmills all wrong - they should be putting the spinning bits Under the water to take advantage of the tidal currents around the UK, these have a number of advantages: -
1) There's much more energy density in all that dense water that's moving around (even if it doesn't move as quickly as the wind)
2) Most importantly, tidal currents are very, very predictable (unlike the wind). You can easily work out years ahead exactly how much energy you are going to be getting from each tidal turbine.
3) Although any tidal turbine is going to experience times of slack water, the nature of tides is such that given a sufficient geographic spread, this will happen at different times in different places.
4) Tidal turbines are effectively invisible - the business end is entirely underwater. (Although there are, of course, questions about the effect of spinning blades on fish, and the problems of fishing boats.) Compare that to a 1000ft high windmill.
Some estimates put the amount of energy available around the Channel Islands (off the northwest coast of France) at anything up to 25GW - which is hardly surprising given a local tidal range of 10-12m.
Other areas around the UK (such as the Bristol Channel) have an equally high potential.
Why aren't we putting more effort into developing what seems to be the ultimate renewable energy resource - reliable, predictable, and with minimal impact on the environment?
Down time should not be an issue with a well maintained server system. I've had experience with systems on these lines that had uptimes measured in years. (They were running UNIX or VMS in those days of course, not Windows.).
If you are worrying about the time you would loose on the very rare occasion that a server goes down - ask yourself how much time you waste wating for your desktop PC to startup/shutdown?
Personally I can recall the days of the VT220 terminal. Boot time was a couple of seconds. I could come into work, turn it on, log in and start working immediately. Even sharing the same server with 20 other developers, it seemed faster to me.
Today I come into work, turn on the PC and then go and make a cup of tea. If I'm lucky it's ready to log in by the time I've done that. Then it's time to make another cup of tea while Windows churns through whatever it does when I first log in (i.e. running all the anti-virus/spyware that cripples my computer for the first five minutes of the day).
It's probably not an exageration to say that I loose ten minutes every day to this sort of activity.
I could also talk about the problems of trying to shut down Windows. Who hasn't tried to shut it down, turned the monitor off, gone home and come back the next day to find a message saying "Application XXXX didn't want to stop. Do you want to terminate it?" So you then have to wait even longer for W£$%£$$%s to shutdown and start up again.
I could of course leave my computer on overnight, but that only works till the oil runs out or rising sea levels drown my office!
Look at electic trains - the TGV in Europe has a continuous rating of 3-8MW. They have been running quite happily for well over 20 years. In that light drawing 1-2MW at a filling station for 5 minutes doesn't seem particularly challenging. There are a number of ways aoround the problems that have been raised here: -
We use Leica DGPS equipment with our own DGPS base station. Accuracy depends on how far you are from the base station, but on our fairly small island we reckon on 1-2 cm accuracy, horizontally and vertically.
This does depend on having sufficient satellites in view - this is a problem under trees and close to buildings and steep slopes.
I don't think that cable length is the main problem. A geostationary (lunostationary?) orbit around the moon is only about twice the radius of a similar orbit around.
By my calculations it should be quite possible to build a space elevator to the lunar surface with a tether made of Kevlar. Such a cable would only require a taper of around 1.7, which seems quite reasonable.
Of course there's the problem of getting a few thousand tons of kevlar up there in the first place...
It seems to me that the problems of building a Space Elevator would be significantly reduced if be built one from the lunar surface. With one-sixth of the gravity of the earth, would it be practical to build a space elevator to the lunar surface with currently available materials?
Might this not be a useful exercise to demonstrate the feasibility of the "Space Elevator" concept, while also giving us relatively easy access to the lunar surface?