We can not really store power at the levels we consume. One of the best ways we have to store power is to pump water uphill to some storage basin and then later generate power from having it flowing downhill again... not very efficient, limited in capacity depending on location and not feasible in all locations.
Routing power is a bit more complex than routing a packet.
For one, a packet is a discrete amount of information, while power is a complex analog phenomenon. You can put a packet on a link and hope it gets there, you can't just put a kilowatt on a power line...
A more conceptual difference is how demand is distributed. A network client talks to a few distributed servers on the Internet. A power client just demands power and does not care where it comes from or if the server cannot deliver it. When a server gets overloaded, the clients just have to wait. If a power plant gets overloaded and the power cannot be gotten elsewhere, the service of the whole network goes down (voltage drops) unless some of the load is cut. If a certain network link is overloaded, packets get dropped. If a power line is overloaded, (hopefully) circuit breakers pop and ALL power transfer is interrupted.
Some practical problems you will run into with power switching:
power conversion - the power grid is not uniform. There are several types of high-voltage lines and power needs to be converted to route power between them. Those conversions introduce losses and have capacity limits.
transport losses - each length of power cable introduces loss.
power plant characteristics - each power source has its own characteristics. For example, the output of a nuclear power plant is more or less constant and cannot adjusted to changing demand.
changing demand - power demand changes drastically over the course of a day, both in level and geographically. During office hours, power is needed in office buildings, during the evening in households,...
load characteristics - inductive load vs capacitive load. In ideal situations, you would combine them to get a resistive load as much as possible as this leads to optimum power efficiency.
politics - which, I have read on the Internet, is one of the major sources of blackouts in the US.
As an aside to the last point, I wonder why blackouts happen so regularly in the US while the are exceedingly rare in Europe. I am in Belgium and I get a "blackout" once every decade or something. I do sometimes experience glitches where you see the lights dim and computers with lousy power supplies reboot... once every few years or so. It suggests to me, whatever the problem is, it isn't technical...
Exactly. And people that do want to play pirated games will just buy a second console...
Which means that the loss on the hardware will be twice as large for Sony, with no increase in software sales...
How about a few thousand solar satellites in orbit around the sun, transmitting energy directly to power stations on earth where the energy gets redistributed?
How about no more batteries?
Driving cars that get their energy straight from the sun?
Cellphones that do not just get their energy through an entangled pair, but also their 'net connection?
Or why not just dump one of those entangled particles into the sun? Or, if we're feeling particularly paranoid, into a neighboring star?
No. It has to do with the impedance of the cables.
Since there is a lot of empty space around the powerlines in the air, there is very little loss from the electromagnetic field that is generated around the conductors by the power flowing through it.
If you bury the cables, there is a lot more electrically conductive material near the power lines creating more loss of power. In effect, the power cables would lose a lot of power heating the ground around it.
At least, if I remember my classes correctly.
If you're cooking YOU'RE IN THE DAMNED KITCHEN! Why in hell would you want to access your kitchen appliances from a telephone or a videogame?
So you can cook WITHOUT being in the damned kitchen? I would love to have a gkrell like app monitoring the temperature and humidity in my pots, maybe include some video.
It would have saved me a shitload of broken nails trying to get the burned black bits out of my cooking pots...
I am running a system based on an Atom 330 motherboard from Intel. It has 2GB of memory and a 320GB harddisk. I payed about 300 euros for the complete system, but you can probably get it cheaper. The motherboard with cpu was 70 euro.
I like it because it is powerful enough to do most of my daily computing. It runs an apache, a mailserver and serves as my desktop machine. I use a 1680x1050 Gnome desktop, fullscreen video, browser and email client. It has, in practise, completely replaced my normal (1300 euro) desktop. After I replaced the crappy fan that came with the motherboard it is now perfectly silent.
If you make an image of your platter with an electron microscope you can measure the actual magnetisation of the bit (which is an analog value) on the harddrive and have a good idea of what previous values were. Add to that the error correction mechanisms on every harddrive and you have a good chance to find the data on it before you put all zeroes over it.
I have no idea of the real code behind those file systems but I find "external calls" a bit of an weird metric. The more "common code" used by the file systems, the more "external calls" would be seen, while this would actually be a Good Thing.
Well, I just installed recent Intel drivers om my new Atom 330 machine (with a builtin 945G) and I am pleasantly surprised about stability and performance (both graphics and cpu). It can't compete with my main machine but it does the browse/chat/video thing smoothly.
I think it would require listening to changes on every directory on the filesystem with an active daemon. You could keep the database up-to-date like that, but I can assure you lots of overhead when doing file manipulations. (compiling, unzipping...).
I'm unsure what you mean with breaking something of POSIX, but it would mostly likely ruin your "computing experience".
Doesn't the Army provide you with help in this department? I cannot imagine they do not have anyone on Dells side of the ocean that can help you deal with issues like this.
Install a caching proxy server. For example, install an old linux PC with Squid. It may not be as useful for a single user as for a group but should help a bit.
Use Firefox with an ad block extension: blocks banners etc, reducing the amount of images you load.
It would be interesting to know if this would not just train the brain to warn you in those cases too. You are creating what could be considered a correcting feedback loop.
The question is, where do you make your brain draw the line and will it not teach the brain to just turn off all filters...
If you have line of sight between the houses, just connect some good antennas to standard wireless accesspoints (dishes for example) and put the antennas on the roof. You should be able to cross those 500m. Outdoor units would indeed help.
I did 1200m with two homemade can antennas (across a valley though). A few years ago, a suitable dish costs around $75.
Where it is true or not is not proven. That makes it a theory.
Which, I might add, makes God a theory too. His existance is also stated with much unproven authority.
At least evolution makes sense.
It is rare that you can completely separate every context of every step of your processing. There is always some data that needs to be shared between the threads and they become bottlenecks. The faster you serve your requests, the worse the contention (waiting for a resource) and thus the inefficiency.
It depends on the task at hand and on your architecture. A file or web server is less likely to encounter contention than for example an IRC server. The first requires some authentication and resource resolving through configuration data but the actual data can be send without interference from other requests. An IRC server requires constant lookups in the user database for routing information and this is likely to take longer than actually sending the messages (even without multi-threading). In these cases, you really have to think your locking scheme through or you will lose more time waiting for a lock than doing actual work - defeating much of the purpose of going MT.
When it comes to architecture, multi threading is an option in your architecture, not an architecture in itself. There is no problem doing a multi-threaded event-driven architecture or a MT message passing architecture -- these are actually very effective. For some interesting reading about this, I would suggest you check out the SEDA white paper for a pretty in depth list of options and their goals.
Why is it bad for programmers? Because locking is hard to do in itself and if your locking scheme is subobtimal it often requires a lot of work to change it afterwards.
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Interesting, can we store power on that level with compressed air?
The fact that I live within 10km from the nearest nuclear plant probably doesn't hurt either...
We can not really store power at the levels we consume. One of the best ways we have to store power is to pump water uphill to some storage basin and then later generate power from having it flowing downhill again... not very efficient, limited in capacity depending on location and not feasible in all locations.
For one, a packet is a discrete amount of information, while power is a complex analog phenomenon. You can put a packet on a link and hope it gets there, you can't just put a kilowatt on a power line...
A more conceptual difference is how demand is distributed. A network client talks to a few distributed servers on the Internet. A power client just demands power and does not care where it comes from or if the server cannot deliver it. When a server gets overloaded, the clients just have to wait. If a power plant gets overloaded and the power cannot be gotten elsewhere, the service of the whole network goes down (voltage drops) unless some of the load is cut. If a certain network link is overloaded, packets get dropped. If a power line is overloaded, (hopefully) circuit breakers pop and ALL power transfer is interrupted.
Some practical problems you will run into with power switching:
As an aside to the last point, I wonder why blackouts happen so regularly in the US while the are exceedingly rare in Europe. I am in Belgium and I get a "blackout" once every decade or something. I do sometimes experience glitches where you see the lights dim and computers with lousy power supplies reboot... once every few years or so. It suggests to me, whatever the problem is, it isn't technical...
He just has Reason
Am I the only one that thinks 0.002 Watt x 500 does not make 100 Watt?
Exactly. And people that do want to play pirated games will just buy a second console... Which means that the loss on the hardware will be twice as large for Sony, with no increase in software sales...
You can find pictures here... http://www.electrolux.com.br/ikitchen_ra/
http://www.youtube.com/watch?v=Gh_RgvmO3bQ and my favorite: http://www.youtube.com/watch?v=PiYuq6Ac3a0 Aaaaah... good times.
How about a few thousand solar satellites in orbit around the sun, transmitting energy directly to power stations on earth where the energy gets redistributed?
How about no more batteries?
Driving cars that get their energy straight from the sun?
Cellphones that do not just get their energy through an entangled pair, but also their 'net connection?
Or why not just dump one of those entangled particles into the sun? Or, if we're feeling particularly paranoid, into a neighboring star?
No. It has to do with the impedance of the cables. Since there is a lot of empty space around the powerlines in the air, there is very little loss from the electromagnetic field that is generated around the conductors by the power flowing through it. If you bury the cables, there is a lot more electrically conductive material near the power lines creating more loss of power. In effect, the power cables would lose a lot of power heating the ground around it. At least, if I remember my classes correctly.
So you can cook WITHOUT being in the damned kitchen? I would love to have a gkrell like app monitoring the temperature and humidity in my pots, maybe include some video.
It would have saved me a shitload of broken nails trying to get the burned black bits out of my cooking pots...
I like it because it is powerful enough to do most of my daily computing. It runs an apache, a mailserver and serves as my desktop machine. I use a 1680x1050 Gnome desktop, fullscreen video, browser and email client. It has, in practise, completely replaced my normal (1300 euro) desktop. After I replaced the crappy fan that came with the motherboard it is now perfectly silent.
The whole system, under load, uses 28Watt.
If you make an image of your platter with an electron microscope you can measure the actual magnetisation of the bit (which is an analog value) on the harddrive and have a good idea of what previous values were. Add to that the error correction mechanisms on every harddrive and you have a good chance to find the data on it before you put all zeroes over it.
I have no idea of the real code behind those file systems but I find "external calls" a bit of an weird metric. The more "common code" used by the file systems, the more "external calls" would be seen, while this would actually be a Good Thing.
Well, I just installed recent Intel drivers om my new Atom 330 machine (with a builtin 945G) and I am pleasantly surprised about stability and performance (both graphics and cpu). It can't compete with my main machine but it does the browse/chat/video thing smoothly.
I think it would require listening to changes on every directory on the filesystem with an active daemon. You could keep the database up-to-date like that, but I can assure you lots of overhead when doing file manipulations. (compiling, unzipping...).
I'm unsure what you mean with breaking something of POSIX, but it would mostly likely ruin your "computing experience".
Doesn't the Army provide you with help in this department? I cannot imagine they do not have anyone on Dells side of the ocean that can help you deal with issues like this.
If you have any important data on your PC, you should make backups. Enclosure or not, your hard drive might fail at any time.
Try this:
Install a caching proxy server. For example, install an old linux PC with Squid. It may not be as useful for a single user as for a group but should help a bit.
Use Firefox with an ad block extension: blocks banners etc, reducing the amount of images you load.
EVE? http://www.eve-online.com/
It would be interesting to know if this would not just train the brain to warn you in those cases too. You are creating what could be considered a correcting feedback loop.
The question is, where do you make your brain draw the line and will it not teach the brain to just turn off all filters...
If you have line of sight between the houses, just connect some good antennas to standard wireless accesspoints (dishes for example) and put the antennas on the roof. You should be able to cross those 500m. Outdoor units would indeed help.
I did 1200m with two homemade can antennas (across a valley though). A few years ago, a suitable dish costs around $75.
Where it is true or not is not proven. That makes it a theory. Which, I might add, makes God a theory too. His existance is also stated with much unproven authority. At least evolution makes sense.
It is rare that you can completely separate every context of every step of your processing. There is always some data that needs to be shared between the threads and they become bottlenecks. The faster you serve your requests, the worse the contention (waiting for a resource) and thus the inefficiency.
It depends on the task at hand and on your architecture. A file or web server is less likely to encounter contention than for example an IRC server. The first requires some authentication and resource resolving through configuration data but the actual data can be send without interference from other requests. An IRC server requires constant lookups in the user database for routing information and this is likely to take longer than actually sending the messages (even without multi-threading). In these cases, you really have to think your locking scheme through or you will lose more time waiting for a lock than doing actual work - defeating much of the purpose of going MT.
When it comes to architecture, multi threading is an option in your architecture, not an architecture in itself. There is no problem doing a multi-threaded event-driven architecture or a MT message passing architecture -- these are actually very effective. For some interesting reading about this, I would suggest you check out the SEDA white paper for a pretty in depth list of options and their goals.
Why is it bad for programmers? Because locking is hard to do in itself and if your locking scheme is subobtimal it often requires a lot of work to change it afterwards.