OK, '640mm effective' or '640mm equivalent' are bad nomenclature. The problem is that in the past there was only 35mm, so focal lengths were usually used instead of angle of view. And the tradition has gone on of quoting an equivalent focal length for small sensor lenses, because it is easier for people to compare different cameras by using the 'equivalent' focal length - People have a good feel of what to expect from a 200mm lens compared to a 28mm lens.
Its too late to change it. Just get used to it - a 840mm lens no longer means a lens with a focal length of 840mm. It means a lens with the same angle of view that an 840mm lens would have with a 35mm image frame. This makes things especially confusing when the same lens might be used with a full-frame or APS-C size sensor. You can blame the journalists (so tedious to always say 'equivalent') or the camera manufacturers (what would sell better 5-100mm or 25-500mm?), but it isn't going to change things.
It is rather like using equivalent MHz as a CPU speed measurement unit.
But the point is that these smaller cameras can have amazingly small angle of view. Smaller than almost any DSLR lens. You can get a camera which has the same angle of view as an 840mm lens on a 35mm camera, and it will resolve more detail than than many older full-frame DSLRs (in the right conditions). In good lighting conditions these can take excellent pictures. A DSLR will take better pictures in less well lit conditions, may focus more quickly and more accurately, and may take more pictures in quick succession. And a picture taken in good conditions with a long DSLR lens might resolve more detail than a good small camera. But there is not very much in it - and a small camera is certainly easier to carry around and handle. (And in Kuwait in daylight I expect the lighting conditions are quite bright).
With a small sensor you get a greater depth of field (for the same angle of view and aperture). But you get greater problems with diffraction - some cameras reach the diffraction limit at f5.6, so stopping down does not improve the image.
p.s. I am aware of medium and large format in addition to 35mm. But they were (are) always relatively specialised, and people who used them know what they are talking about and dont buy things based on meaningless paper specs, unlike many of the people who talk about 35mm equivalent focal length.
But with the Euro the individual governments have already surrendered those abilities to a central authority. Which is why some countries are finding it difficult to work their way out of current financial difficulties.
The section you are quoting is about heat engines. A light bulb produces no mechanical work (and also take no heat in from a hot bath). The equation simply does not apply. The desired output is Qout - it is not 'waste heat'. In this case efficiency is Qout/Win (Win being the electrical energy input to the system).
The section you should refer to is the 'Energy Conversion' section, which actually says that an electric resistance heater has near 100% thermal efficiciency.(Qin=0, Wout=0, Qout/Win=1). You might say that Wout is not zero if some of the energy escapes (through the windows) as light energy.
You are correct though in saying that a heat pump is more efficient than a resistance heater - in this case Qin>0, Wout=0, Qout=Qin+Win, and Qout/Win>1.
The above post is typical of a lot of errors that various people are making here. GW/h is not the same thing as GWh. 1GW/h is not a measure of energy. It might be a measure of the rate of change of power (it is rather absurb, but that is the point of the previous reply which was intended to be humorous).
The measure of energy could be in kWh, MWh or GWh.
It's true that an electric motor provides more torque than an internal combustion engine at low revs. The shape of the toque curve is very different. An electric motor can provide a lot of torque at 0 rpm, while an internal combustion engine can't even keep itself turning at very low revs.
This means that the power curve has a different shape. An electric motor has a much broader curve, so it is able to run with high power over a large range of speeds. So much so that it wont need a clutch, and may not need different gear ratios. It may still need some kind of gearbox to match the rpm of the motor to that of the wheels, but a single speed box is sufficient in many cases (possibly not if you want to get the max possible performance).
Wide tires dont give you extra contact area. The area of contact between the tyre and the road is determined mostly by the air pressure in the tyre. If you increase the width of the tyre without changing the pressure then you change the shape of the contact patch, but not its area (not much anyway). Wide tyres are useful because they are less affected by irregularities in the road surface and because they spread the load through a large area of rubber (so they dont overheat so quickly). The contact patch is also short and wide, which means that the front and rear edges of the contact patch are longer (and these edges carry a bit more of the load than the centre due to the bending of the rubber). An Ultra-wide (steamroller) tyre would not be useful. It would require some internal structure to transfer weight to the centre of the tyre (otherwise it would bend and just lie on the road surface in the middle with very little pressure). It would also cause cornering problems - how would you provide a differential? Wide tyres already have problems cornering due to the difference in road speed between the inside and outside edges - there is bound to be some slippage. Narrower tyres are usually more efficient. The only practical way to increase traction is to provide extra downforce (e.g. aerodynamic - which only works at speed) or to use all 4 wheels for traction (doing something to the materials of the tyre/road and the tread pattern also have some effect).
It should be easy enough to add a sealed USB socket to the case. So you connect the USB port on the cammera to a lead which runs to the USB socket. This socket can have a waterproof cover which you remove when you want to connect to your PC/charger. It would be easy to seal the USB socket cover, as it can be round and screwed down with O-ring seals. This could be done with todays cameras - if they allowed you to charge the battery via the USB connection.
You could also test the seals on the case before diving.
You would need a chamber large enough to contain the camera in its case. Pressurize the chamber and watch a pressure gauge inside the case - if the gauge does not rise then you have a good seal.
So what you want is a case manufacturer to build a housing with an external power/usb connector. The power could be used to charge batteries in the housing which drive any electronics in the housing, and also provide power to the camera (via its DC connector) and any strobe lights. The housing would also have a built-in pressure gauge for testing. This would probably be cheaper than buying a new camera, and could be applied to any existing camera.
The principles of Public Key Cryptography are still secure (at the moment). But the practice is not. Whatever key size you choose will only be secure for some period of time.
Only a few years ago people were using quite short keys (1K bits). These are no longer secure. Anything using such keys can possibly now be broken (with some effort). If you relied on 512 bit keys then your 'long term' has already expired.
No diesel car I have had has used spark plugs.
They all have plugs, which from the outside look a bit like spark plugs.
But they dont spark - they 'glow'. If you look you will see they are all wired in parallel - and they receive a continuous voltage when the engine is cold. They are used during starting to provide a hot spot which will ignite the fuel in a cold engine.
What if the encryption technique is not one that the USB device understands?
I dont mean the algorithm used (AES etc), but the way the password is converted to the encryption key.
Even if you give him the password, the USB device wont be able to decrypt anything.
But doing the modifications in place is not safe if you might get a system crash (or power failure).
What you could do is to create a backup file and then do the write in place. You would need some kind of procedure to restore the backup if the original write did not complete properly.
I suppose you really want to have a file system primitive which says 'open a temporary file for writing as a new version of this other file'. When you close the temporary file the filesystem would atomically replace the contents of the original file with the temporary file, preserving all attributes such as ACLs (unless you modified them on the temporary version). You could go further and arrange that the temporary file started off with the same contents as the original file - so the entire update sequence became a single transaction.
I would expect the charge to mass ratio to be more important than the mass alone. The He nucleus has twice the charge as an H nucleus. So He4 has the same charge/mass ratio as H2, and a greater ratio than H3.
So if some other state fancies being first why dont they pass their own state law that says that? Surely Iowa and New Hampshire laws dont apply to other states?
If I were some non-american government then I would prefer people to use Linux. Not because of any backdoors that I could put in it, but because I could be reasonably sure that there were no backdoors put in it by the US government.
Sounds like you need a simple proxy server whose only job is to insert the cookie. Then direct all your clients to use the proxy server. Could even be a transparent proxy in your router.
The only thing that's worse is that they might feel secure when they're not.
That is exactly what an ISP would want. You would have the correct URL, the correct IP address and everything would look correct. But your traffic would be monitored by the ISP (in some kind of transparent proxy).
Being able to save a certificate and not having a message pop up every time it is seen would be useful. The first time you came across a certificate you should get a warning message. But if you can manually verify the certificate then you should be able to silently accept it in the future.
But the engine in a truck or bus is not fixed speed. It varies according to driving conditions, and there is a loss in efficiency due to the need to allow for the flexible load. If you use an engine merely for charging the battery then it can be a fixed speed, fixed load engine - I.e. it can run at peak efficiency whenever it is running, and the efficiency can be higher than a more flexible engine.
It would be very easy for an ISP to perform man-in-the-middle attacks on supposedly secure sites which use self-signed certificates. Self-signed certificates provide some security against eavedropping by third parties, but almost none against a malicious network. They can only be useful if you have some independent method of verifying them, and very few people would know how to do that. (Of course, that also applies to certificates signed by many certifying agencies - it is probably quite easy to get a fake certificate that will be silently accepted by browsers)
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I found that 14.04 LTS would not run with the latest kernel under vmware But it has been updated and now does run (3.19.0-51)
OK, '640mm effective' or '640mm equivalent' are bad nomenclature.
The problem is that in the past there was only 35mm, so focal lengths were usually used instead of angle of view.
And the tradition has gone on of quoting an equivalent focal length for small sensor lenses, because it is easier for people to compare different cameras by using the 'equivalent' focal length - People have a good feel of what to expect from a 200mm lens compared to a 28mm lens.
Its too late to change it. Just get used to it - a 840mm lens no longer means a lens with a focal length of 840mm. It means a lens with the same angle of view that an 840mm lens would have with a 35mm image frame. This makes things especially confusing when the same lens might be used with a full-frame or APS-C size sensor. You can blame the journalists (so tedious to always say 'equivalent') or the camera manufacturers (what would sell better 5-100mm or 25-500mm?), but it isn't going to change things.
It is rather like using equivalent MHz as a CPU speed measurement unit.
But the point is that these smaller cameras can have amazingly small angle of view. Smaller than almost any DSLR lens. You can get a camera which has the same angle of view as an 840mm lens on a 35mm camera, and it will resolve more detail than than many older full-frame DSLRs (in the right conditions).
In good lighting conditions these can take excellent pictures. A DSLR will take better pictures in less well lit conditions, may focus more quickly and more accurately, and may take more pictures in quick succession. And a picture taken in good conditions with a long DSLR lens might resolve more detail than a good small camera. But there is not very much in it - and a small camera is certainly easier to carry around and handle. (And in Kuwait in daylight I expect the lighting conditions are quite bright).
With a small sensor you get a greater depth of field (for the same angle of view and aperture). But you get greater problems with diffraction - some cameras reach the diffraction limit at f5.6, so stopping down does not improve the image.
p.s.
I am aware of medium and large format in addition to 35mm. But they were (are) always relatively specialised, and people who used them know what they are talking about and dont buy things based on meaningless paper specs, unlike many of the people who talk about 35mm equivalent focal length.
But with the Euro the individual governments have already surrendered those abilities to a central authority. Which is why some countries are finding it difficult to work their way out of current financial difficulties.
Wrong.
The section you are quoting is about heat engines. A light bulb produces no mechanical work (and also take no heat in from a hot bath). The equation simply does not apply. The desired output is Qout - it is not 'waste heat'. In this case efficiency is Qout/Win (Win being the electrical energy input to the system).
The section you should refer to is the 'Energy Conversion' section, which actually says that an electric resistance heater has near 100% thermal efficiciency.(Qin=0, Wout=0, Qout/Win=1). You might say that Wout is not zero if some of the energy escapes (through the windows) as light energy.
You are correct though in saying that a heat pump is more efficient than a resistance heater - in this case Qin>0, Wout=0, Qout=Qin+Win, and Qout/Win>1.
The above post is typical of a lot of errors that various people are making here. GW/h is not the same thing as GWh.
1GW/h is not a measure of energy. It might be a measure of the rate of change of power (it is rather absurb, but that is the point of the previous reply which was intended to be humorous).
The measure of energy could be in kWh, MWh or GWh.
So 6 equal sides of 9 sq/ft would make it 81 cubic feet.
I think you mean 27 cubic feet (assuming square sides).
... except you and Google.
It's true that an electric motor provides more torque than an internal combustion engine at low revs.
The shape of the toque curve is very different.
An electric motor can provide a lot of torque at 0 rpm, while an internal combustion engine can't even keep itself turning at very low revs.
This means that the power curve has a different shape. An electric motor has a much broader curve, so it is able to run with high power over a large range of speeds. So much so that it wont need a clutch, and may not need different gear ratios. It may still need some kind of gearbox to match the rpm of the motor to that of the wheels, but a single speed box is sufficient in many cases (possibly not if you want to get the max possible performance).
Wide tires dont give you extra contact area. The area of contact between the tyre and the road is determined mostly by the air pressure in the tyre. If you increase the width of the tyre without changing the pressure then you change the shape of the contact patch, but not its area (not much anyway). Wide tyres are useful because they are less affected by irregularities in the road surface and because they spread the load through a large area of rubber (so they dont overheat so quickly). The contact patch is also short and wide, which means that the front and rear edges of the contact patch are longer (and these edges carry a bit more of the load than the centre due to the bending of the rubber). An Ultra-wide (steamroller) tyre would not be useful. It would require some internal structure to transfer weight to the centre of the tyre (otherwise it would bend and just lie on the road surface in the middle with very little pressure). It would also cause cornering problems - how would you provide a differential? Wide tyres already have problems cornering due to the difference in road speed between the inside and outside edges - there is bound to be some slippage. Narrower tyres are usually more efficient. The only practical way to increase traction is to provide extra downforce (e.g. aerodynamic - which only works at speed) or to use all 4 wheels for traction (doing something to the materials of the tyre/road and the tread pattern also have some effect).
HA! Did you really try it?
137/206 works out as zero. As does 2/3.
So your program would pass the vote.
As would
if (1/206 >= 2/3)
votepass;
you need to do something like this
if (137.0/206.0 >= 2.0/3.0)
votepass;
It should be easy enough to add a sealed USB socket to the case. So you connect the USB port on the cammera to a lead which runs to the USB socket. This socket can have a waterproof cover which you remove when you want to connect to your PC/charger. It would be easy to seal the USB socket cover, as it can be round and screwed down with O-ring seals. This could be done with todays cameras - if they allowed you to charge the battery via the USB connection. You could also test the seals on the case before diving. You would need a chamber large enough to contain the camera in its case. Pressurize the chamber and watch a pressure gauge inside the case - if the gauge does not rise then you have a good seal. So what you want is a case manufacturer to build a housing with an external power/usb connector. The power could be used to charge batteries in the housing which drive any electronics in the housing, and also provide power to the camera (via its DC connector) and any strobe lights. The housing would also have a built-in pressure gauge for testing. This would probably be cheaper than buying a new camera, and could be applied to any existing camera.
Because MS is still selling XP?
The principles of Public Key Cryptography are still secure (at the moment). But the practice is not. Whatever key size you choose will only be secure for some period of time. Only a few years ago people were using quite short keys (1K bits). These are no longer secure. Anything using such keys can possibly now be broken (with some effort). If you relied on 512 bit keys then your 'long term' has already expired.
A foot pound is a unit of energy, not force.
No diesel car I have had has used spark plugs. They all have plugs, which from the outside look a bit like spark plugs. But they dont spark - they 'glow'. If you look you will see they are all wired in parallel - and they receive a continuous voltage when the engine is cold. They are used during starting to provide a hot spot which will ignite the fuel in a cold engine.
What if the encryption technique is not one that the USB device understands? I dont mean the algorithm used (AES etc), but the way the password is converted to the encryption key. Even if you give him the password, the USB device wont be able to decrypt anything.
I suppose you really want to have a file system primitive which says 'open a temporary file for writing as a new version of this other file'. When you close the temporary file the filesystem would atomically replace the contents of the original file with the temporary file, preserving all attributes such as ACLs (unless you modified them on the temporary version). You could go further and arrange that the temporary file started off with the same contents as the original file - so the entire update sequence became a single transaction.
Saving data ought to be automatic, without requiring the user to do anything.
I would expect the charge to mass ratio to be more important than the mass alone. The He nucleus has twice the charge as an H nucleus. So He4 has the same charge/mass ratio as H2, and a greater ratio than H3.
There are 4 apostrophes. All correct. (court's, it's, you're, you're)
So if some other state fancies being first why dont they pass their own state law that says that? Surely Iowa and New Hampshire laws dont apply to other states?
If I were some non-american government then I would prefer people to use Linux. Not because of any backdoors that I could put in it, but because I could be reasonably sure that there were no backdoors put in it by the US government.
Sounds like you need a simple proxy server whose only job is to insert the cookie. Then direct all your clients to use the proxy server. Could even be a transparent proxy in your router.
The only thing that's worse is that they might feel secure when they're not.
That is exactly what an ISP would want. You would have the correct URL, the correct IP address and everything would look correct. But your traffic would be monitored by the ISP (in some kind of transparent proxy).
Being able to save a certificate and not having a message pop up every time it is seen would be useful. The first time you came across a certificate you should get a warning message. But if you can manually verify the certificate then you should be able to silently accept it in the future.
But the engine in a truck or bus is not fixed speed. It varies according to driving conditions, and there is a loss in efficiency due to the need to allow for the flexible load. If you use an engine merely for charging the battery then it can be a fixed speed, fixed load engine - I.e. it can run at peak efficiency whenever it is running, and the efficiency can be higher than a more flexible engine.
It would be very easy for an ISP to perform man-in-the-middle attacks on supposedly secure sites which use self-signed certificates. Self-signed certificates provide some security against eavedropping by third parties, but almost none against a malicious network. They can only be useful if you have some independent method of verifying them, and very few people would know how to do that. (Of course, that also applies to certificates signed by many certifying agencies - it is probably quite easy to get a fake certificate that will be silently accepted by browsers)