So, the right way to synchronize systems is not to use Unix time but the number of seconds (or fractions thereof) since a defined point in time. Use GPS time.
Which leaves two problems to be solved in a practical implementation:
1. You have to use GPS receivers which actually shows true GPS time, not GPS time corrected to UTC. As someone has stated in another part of the discussion, GPS receivers will receive GPS time from the satellites, but they also receive a UTC correction which is calculated into the time which is reported by the device.
2. You have to chose how you will handle this in your network, across different platforms: 2a: Let your time daemons run GPS time internally (using your own GPS-based NTP servers for synchronization). This means that you will have to implement time correction in all software which needs to know/display correct UTC time. 2b: Let your time daemons run GPS time internally but report UTC time to any software which asks. This means that you probably will have to develop your own time daemon for all platforms in use in your network, unless solutions already exists.
My point is that it is too easy to just say "What I find baffling is that architects/developers working in such a life-critical field managed to conceive application relying on days/minutes which are NOT fixed values."
When the recognized de facto industry standard of timekeeping doesn't have an optimal solution for leap seconds, there is a very hard choice between doing things right and risk adding your own errors in your home-made solution or doing things less right and at least use a proved solution.
Unix time is kept in the only unit that doesn't change: seconds elapsed since a defined point in time (milliseconds actually, but the base unit is the second).
Sorry, but that is exactly the point. Unix time was given as an example of a correct time implemention using a fixed base, but as far as I can see, it does not use a fixed base in this particular case. If it did, ntp deamons on unix systems would not have to slew or jump the kernel clock when a leap second is inserted.
GPS uses its own time scale that isn't affected by leap seconds.
I don't doubt that it does that internally, but GPS receivers usually put a timestamp on the position. How is this timestamp affected?
Will a GPS receiver continue to convert the internal time to UTC following an outdated algorithm which is hardcoded into the receiver, or is the conversion algorithm part of the data received from the satellites?
In other words: Can we trust the time from a GPS receiver, or will two receivers show a difference of N seconds, depending on how many leap seconds we have had since each GPS receiver was new.
the clock of a Un*x system is usually calibrated in milliseconds since the epoch and this has absolutely zero, nada, zilch, nothing to do with leaps seconds. The fact that we decide that 31 dec 2008 with have a 61 seconds minute change *nothing* to the correct calibration of the clock.
Is that true?
I know that this is how timezones, DST and leap years are handled, but are leap seconds handled like this too?
In other words, if I ask a Un*x system about the number of seconds since epoch for 2008-12-31 23:59:58 UTC and 2009-01-01 0:00:01 UTC will there be a difference of three or four seconds?
Well, it is easy to test, so why do I ask? $ date --utc --date "2008-12-31 23:59:58" +%s 1230767998 $ date --utc --date "2009-01-01 00:00:01" +%s 1230768001
Difference is three seconds, not four. It seems you are wrong, or my Debian Stable has an incorrect implementation of unix time.
There are many ideas for storing wind power, but I don't think batteries should be considered an option unless some radical advancements are made. Water electrolysis, pumping water uphill, etc are all much better ideas.
Actually, water electrolysis is really, really bad.
Not so many years ago, I read that the complete efficiency of a "storage cycle" using hydrogen was somewhere around 30-40% when combining the best known methods for each step in the process.
This should be compared to 70-85% for pumped storage, and apparently around 90% for the battery technology used in the article.
Umm.. building a hydroplant is expensive.. if you have the choice between putting on a river and not putting it on a river, why would you choose the later?
There are several obvious (sorry, I could not resist using that word) answers to that question. Two of them:
1. Because hydropower options in the area may already be depleted. As an example, I was once told that the largest Swedish river (in terms of available energy) has a theoretical potential of 15 TWh/year, and 14 TWh/year is already utilized for power production, meaning that only a few really expensive or troublesome parts of the river are left.
2. Because it is not necessarily a choice between putting on a river and not putting it on a river. You can also pump water backwards in an existing hydropower plant during off-peak time to get more available energy in peak time. Actually, the first time I saw pump storage, they did exactly that. It was in Switzerland where they bought cheap electricity from the French nuclear power plants at night and used it for backwards pumping in existing hydropower plants.
She knew the correct answer. She was deliberately misstating the law in order to improperly inflame the jury against Ms. Thomas, convincing the jurors that even had Ms. Thomas done nothing but copy some CD's onto her hard drive, that in and of itself was a copyright infringement.
Sorry to play the devil's advocate, but was that wrong of her, even if she was deliberately lying?
Given that we have witnesses to establish facts, not legality, does a witness commit perjury when she lies about legality?
If this was not perjury, it seems to me that she was doing her job to her best ability.
But was the defendant's lawyer doing his job to HIS best ability? Shouldn't he have stopped the irrelevant questioning about legality?
...that making a copy from one's CD to one's computer is 'stealing'."
That one baffled me. I am neither a lawyer nor an American. However, I would assume that a witness' opinion of the legality of a given action is completely irrelevant. Establishing the legality of a given action is a task for the court, not a task for the witness.
So why was a witness asked about the legality of copying a CD?
And why was she breaking her oath (as NYCL is somehow implying) when she did not know the correct answer?
Isn't it obvious that pumped storage isn't cost effective?
I think the obviousness sort of missed me. Would you care to elaborate a little?
I am wondering why 90 GW of pumped storage has been built if it is obvious that it isn't cost effective
An excerpt from the report which was linked to in the summary:
There is over 90 GW of pumped storage in operation world wide, which is about 3 % of global generation capacity.
Pumped storage plants are characterized by long construction times and high capital expenditure (>$1,800/kW). Pumped storage is the most widespread energy storage system in use on power networks.
The price for the battery project discussed in this article is $3,000/kW. Leaves some room for the "more than" in the >$1800/kW for pumped storage.
This is an old dream, but is has almost always been defeated by economy. And according to the article, it still is, though it is getting better:
[i]But it is expensive, costing roughly $3 million per megawatt plus millions for start-up and testing. "Right now, they're a little too expensive," Novachek says.[/i]
Looking at the numbers, it seems like a small-scale test setup. 7 MWh is not much in an 1100 MW wind turbine facility.
t looks like most UPSes make systems *less* reliable on balance. How frequent is a power failure compared to a UPS failure?
One of the more ironic examples:
The truck delivering a new UPS unit to a Danish ISP accidentally hit the electric installation on the street outside the server center and cut off the power supply to the server center.
Of course, the old UPS was disconnected at that time to make room for the new unit.
If you're going to interpret rendering a page with less "features" as generating a sister site then Mosaic 1.0 is prior art for this patent.
No, that is not what the GP referred to with the Opera Mini example.
Opera (the company) runs a proxy which simplifies the pages before serving them to the clients. Opera Mini (the browser, typically installed on a cell phone) connects thorugh this proxy.
Works beatifully, by the way - except that the proxy seems to take longer and longer to process the pages.
I am not German either, though I did an A-level in the language, but perhaps
Berufsverlierungsfreudenschade
(Shame at the joy of having lost your job?)
No, Schadenfreude was intentional. That word exists (though I am not sure of the spelling). It means that you are happy about other people's misfortune - in this case happy about the company going belly-up.
The sad part is that it took a bunch of forensic experts and a lot of taxpayer dollars several months to convince the court that pornography can appear in popups when browsing the internet that the user didn't explicitly ask for. This is just another reason why computer crimes need special courts to process cases
So one day we say that courts should not judge people's actions differently just because a computer was involved.
And the next day we say that some cases should be judged in different courts just because a computer was involved.
Do you think that the first goal is realistic if we have parallel court systems for those cases?
As aussie_a said, what you describe is in no way similar to a man-in-the-middle attack. 'MITM' refers to be the ability to eavesdrop on and forge network traffic. Fake login pages is part of 'phishing'.
Phishing does not exclude MITM attacks.
If the phishing site acts as a proxy to the real site - as described by the GP - it IS a MITM attack.
I took it one step further, when I installed Ubuntu on her computer I told her that if she ever gets asked for the root password she should call me first. I don't think I've ever been called.
Perhaps because administrative tasks on Ubuntu does not require the root password!
Ubuntu asks for the user's password when requiring root permissions.
Numbers are courtesy of MY ASS. And serve only to demonstrate that it is entirely possible to get usable electricity out of garbage without breaking any laws of physics.
Your message was that ANY net electricity output is a win.
My answer was that it has to be better than existing technology to be considered a win. So ANY is not enough. You have to get 30% electrical output or better to consider it a win.
Slashdot Mirror
Which leaves two problems to be solved in a practical implementation:
1. You have to use GPS receivers which actually shows true GPS time, not GPS time corrected to UTC.
As someone has stated in another part of the discussion, GPS receivers will receive GPS time from the satellites, but they also receive a UTC correction which is calculated into the time which is reported by the device.
2. You have to chose how you will handle this in your network, across different platforms:
2a: Let your time daemons run GPS time internally (using your own GPS-based NTP servers for synchronization). This means that you will have to implement time correction in all software which needs to know/display correct UTC time.
2b: Let your time daemons run GPS time internally but report UTC time to any software which asks. This means that you probably will have to develop your own time daemon for all platforms in use in your network, unless solutions already exists.
My point is that it is too easy to just say "What I find baffling is that architects/developers working in such a life-critical field managed to conceive application relying on days/minutes which are NOT fixed values."
When the recognized de facto industry standard of timekeeping doesn't have an optimal solution for leap seconds, there is a very hard choice between doing things right and risk adding your own errors in your home-made solution or doing things less right and at least use a proved solution.
Sorry, but that is exactly the point. Unix time was given as an example of a correct time implemention using a fixed base, but as far as I can see, it does not use a fixed base in this particular case. If it did, ntp deamons on unix systems would not have to slew or jump the kernel clock when a leap second is inserted.
I don't doubt that it does that internally, but GPS receivers usually put a timestamp on the position. How is this timestamp affected?
Will a GPS receiver continue to convert the internal time to UTC following an outdated algorithm which is hardcoded into the receiver, or is the conversion algorithm part of the data received from the satellites?
In other words: Can we trust the time from a GPS receiver, or will two receivers show a difference of N seconds, depending on how many leap seconds we have had since each GPS receiver was new.
Pun intended?
Is that true?
I know that this is how timezones, DST and leap years are handled, but are leap seconds handled like this too?
In other words, if I ask a Un*x system about the number of seconds since epoch for 2008-12-31 23:59:58 UTC and 2009-01-01 0:00:01 UTC will there be a difference of three or four seconds?
Well, it is easy to test, so why do I ask?
$ date --utc --date "2008-12-31 23:59:58" +%s
1230767998
$ date --utc --date "2009-01-01 00:00:01" +%s
1230768001
Difference is three seconds, not four. It seems you are wrong, or my Debian Stable has an incorrect implementation of unix time.
Actually, water electrolysis is really, really bad.
Not so many years ago, I read that the complete efficiency of a "storage cycle" using hydrogen was somewhere around 30-40% when combining the best known methods for each step in the process.
This should be compared to 70-85% for pumped storage, and apparently around 90% for the battery technology used in the article.
There are several obvious (sorry, I could not resist using that word) answers to that question. Two of them:
1. Because hydropower options in the area may already be depleted.
As an example, I was once told that the largest Swedish river (in terms of available energy) has a theoretical potential of 15 TWh/year, and 14 TWh/year is already utilized for power production, meaning that only a few really expensive or troublesome parts of the river are left.
2. Because it is not necessarily a choice between putting on a river and not putting it on a river. You can also pump water backwards in an existing hydropower plant during off-peak time to get more available energy in peak time.
Actually, the first time I saw pump storage, they did exactly that. It was in Switzerland where they bought cheap electricity from the French nuclear power plants at night and used it for backwards pumping in existing hydropower plants.
Sorry to play the devil's advocate, but was that wrong of her, even if she was deliberately lying?
Given that we have witnesses to establish facts, not legality, does a witness commit perjury when she lies about legality?
If this was not perjury, it seems to me that she was doing her job to her best ability.
But was the defendant's lawyer doing his job to HIS best ability? Shouldn't he have stopped the irrelevant questioning about legality?
...that making a copy from one's CD to one's computer is 'stealing'."
That one baffled me. I am neither a lawyer nor an American. However, I would assume that a witness' opinion of the legality of a given action is completely irrelevant. Establishing the legality of a given action is a task for the court, not a task for the witness.
So why was a witness asked about the legality of copying a CD?
And why was she breaking her oath (as NYCL is somehow implying) when she did not know the correct answer?
You have still not explained why it is obvious.
I think the obviousness sort of missed me. Would you care to elaborate a little?
I am wondering why 90 GW of pumped storage has been built if it is obvious that it isn't cost effective
An excerpt from the report which was linked to in the summary:
The price for the battery project discussed in this article is $3,000/kW. Leaves some room for the "more than" in the >$1800/kW for pumped storage.
This is an old dream, but is has almost always been defeated by economy. And according to the article, it still is, though it is getting better:
[i]But it is expensive, costing roughly $3 million per megawatt plus millions for start-up and testing. "Right now, they're a little too expensive," Novachek says.[/i]
Looking at the numbers, it seems like a small-scale test setup. 7 MWh is not much in an 1100 MW wind turbine facility.
Yes.
0, 1, 2, 3, 10, 11, 12, 13, 20, 21, 22, 23, 30, 31, 32, 33, 100, 101 ...
One of the more ironic examples:
The truck delivering a new UPS unit to a Danish ISP accidentally hit the electric installation on the street outside the server center and cut off the power supply to the server center.
Of course, the old UPS was disconnected at that time to make room for the new unit.
No, that is not what the GP referred to with the Opera Mini example.
Opera (the company) runs a proxy which simplifies the pages before serving them to the clients. Opera Mini (the browser, typically installed on a cell phone) connects thorugh this proxy.
Works beatifully, by the way - except that the proxy seems to take longer and longer to process the pages.
No, Schadenfreude was intentional. That word exists (though I am not sure of the spelling). It means that you are happy about other people's misfortune - in this case happy about the company going belly-up.
We need a "+1 Whoosh" moderation option.
No, I do not mean "-1 Whoosh". I want to see those embarrassingly stupid postings. But perhaps this moderation option should subtract karma.
So one day we say that courts should not judge people's actions differently just because a computer was involved.
And the next day we say that some cases should be judged in different courts just because a computer was involved.
Do you think that the first goal is realistic if we have parallel court systems for those cases?
Then I am happy to live in a country where police have an obligation to find the unbiased truth and present to the court if the case goes that long.
Sorry to hear that you are living in a police state.
Berufsverlierungschadenfreude?
(No, I am not a German and I suck at their language. The above probably contains several errors.)
It is sad that you got modded Flamebait. The idea of +0 moderations is interesting.
But to be fair, I don't think that the GP was ranting. He was just short on line breaks.
He may even have had a lot of carefully inserted line breaks disappear due to lack of preview and lack of knowledge about the ./ editing interface.
Phishing does not exclude MITM attacks.
If the phishing site acts as a proxy to the real site - as described by the GP - it IS a MITM attack.
Perhaps because administrative tasks on Ubuntu does not require the root password!
Ubuntu asks for the user's password when requiring root permissions.
Don't you mean:
Because base-1010 is soooo 11101101100 to 11111001111s.
Your message was that ANY net electricity output is a win.
My answer was that it has to be better than existing technology to be considered a win. So ANY is not enough. You have to get 30% electrical output or better to consider it a win.