Real time systems encounter this ordering problem. They are simple by comparison to most software running today. Priority inversion http://en.wikipedia.org/wiki/Priority_inversion It is not common. Engineers spend a lot of time trying to ensure it does not occur. It is a result of the ordering of access to a shared resource causing a high priority task to be de-scheduled. That is a specific circumstance. pre-emptive schedulers do cause problems so please do not discount them.
By interact I mean access a shared resource. (memory or other) By distribute I mean distribute over multiple processors. Isolated data is not a shared resource. Synchronisation is normally used to provide consistency of the shared resource but not often used to provide overall ordering with regards to accessing it. Hence non determinism. If you can't tell which thread gets to access the shared resource and in which order, the program is no longer deterministic.
non-determinism of this type isn't inherently bad you just have to ensure that it does not matter. or force ordered access when that is possible (not always) Think of a shared linked list as an example. The order of access by the reader and writer is non-deterministic and does not matter except when the list is empty or full when you have to impose and overall order. (writer first, reader first respectively)
No software is simple. Very little software can be analysed effectively. Unless you understand everything from the current machine state, all inputs and exactly what and when they happen, the hardware down to memory refresh, latency cache behaviour, OS behaviour, scheduling policy, other processes and states and their inputs, in addition to your software. It is complex, there is no simple software any more. Even if you claim that that is deterministic then you can still become unstuck if you have multiple physical processors and get non-deterministic behaviour. Note that this has little to do with most issues people have when they claim a computer does such-and-such arbitrarily.
If you have more then one thread running and they interact you no longer necessarily have a deterministic system. If you distribute it it gets even worse. Even in small embedded realtime systems you can get non-deterministic behaviour.
I had not even thought about it. Thinking about it I do use the hand brake quite often. So yes some people with manual gearboxes do use it. Most of the world do not use automatic gearbox's
It is tiny. Know-one knows exactly where it is. Yes NASA did know where it went but not with enough accuracy to tell where it is now. 40 years is a long time to modify and orbit.
I was wondering about that as I had not heard of commercial hardware that could handle anywhere near that bandwidth.If you push it into restricted frequencies it is possible but not anything cheap that I know off. I can get you gigabit wireless links but it is not simple and very much not cheap. Range limited and mostly line of sight. I suppose tech changes so it may be possible.
He plead guilt in court. Perhaps he did do what the prosecution claimed he did? If he had any possible defence he may have taken it. This is not the US so freedom of speech is not quite the same here. You can be prosecuted for writing nasty letters to people. Why is it hard to understand that the same laws will apply to something you do on the internet.
I think the poster did not mean civil offence. There are three kinds of criminal offence in the UK. And the court procedures are different. Summary - magistrate. Inditable - Crown court (jury). Triable either way - you get the choice of magistrates or jury trial.
Not all criminal offences are recorded on your criminal record and not all are declarable. Speeding tickets are (as far as I know) not recorded apart from on you license.
My mother 70 ish now shows allergic reactions to pretty much every test known to man. The only things she is actually allergic to are bee stings and penicillin. And she has ended up in hospital because of bee stings and was already in hospital (different reason) when she had a massive reaction to penicillin (not other antibiotics though) She has to wear a medic aid bracelet warning about penicillin now.
So I don't have much confidence in those tests. If they show positive then your body is overreacting. but not necessarily in a way that is detrimental.
"The whole climate change discussion will go the way of acid rain, ozone layer hole, acid ocean"
So you agree that laws mandating behaviour should be used to limit CO2 emissions to mitigate the effects on the atmosphere. All the other issues you raised had their effects reduced by similar laws an restrictions (sulphur filters on coal fired power station, Banning CFC use in aerosols and cooling systems.
The NHS has quite a wide range of hearing aids that they can prescribe depending on the type of hearing loss you have. You can buy privately as well and still be entitled to free ones from the NHS. They also provide batteries.
In the UK privately purchased hearing aids cost between £500 and £4000.
If it was GPL they would not have touched the code. So you wuld have not just have fragmented versions but entirely written from scratch versions.
I prefer BSD or Apache style licences. But I understand the goal of GPL. It just went to far. LGPL is a good level but it is so poorly defined that any company lawyer looks at it and they start pulling their hair out and shout NO.
Oh you had the joy of installing from 70 odd floppy disks too. I'm glad I was not the only one to suffer. Enough to make me buy a 2x CD rom:) for £220. It did come with an interface card though. My sound card did not support it.
Perhaps you did not realise but bits of BART are underground. There is no frequency allocation. Just repeaters that they own. I fear that they are not obliged to offer service.
It is empirical science. They do not have to have a reason for it. They just have to rule out reasons that they could be due to faulty machinery. And that it does not fit current models. After that it becomes a question of "how an this be explained"
Most new advances in science start with someone saying "WTF?"
The economic effects were far and wide. In the UK we had radioactive sheep because of Chernobyl. Not really but farmers had to put up with massive expense because of it.
Perhaps for use at home voice recognition would work. but in an office? Loads of people talking at their computers? A very noisy environment. Are you sure that is a good idea?
It is useful to correct for barrel distortion no matter how far you fire. Do you think that a minor defect would not throw artillery far off target?
No problem. I was just trying to explain some of the technology being used for long range targets.
Did the Russians develop a gun launched missile? Cool idea but it would probably kill the operator. There were enough problems with the development of the star streak missile. It requires small motor to get it out of the tube without hurting the operator. Then a second to get it up to speed. It would burn the poor bugger who fired it if not. It is a line of sight weapon. Short range of about 7 km with the mk2. Designed for hitting aircraft but I think there have been successes against ground targets.
I know that I could not consistently hit a barn door at 2.5 kilometres let alone 2.3. Doing it multiple times... shockingly good! I do not think that killing people is a good idea but they both did the job asked of them and excelled at it.
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Real time systems encounter this ordering problem. They are simple by comparison to most software running today. Priority inversion http://en.wikipedia.org/wiki/Priority_inversion
It is not common. Engineers spend a lot of time trying to ensure it does not occur. It is a result of the ordering of access to a shared resource causing a high priority task to be de-scheduled. That is a specific circumstance. pre-emptive schedulers do cause problems so please do not discount them.
By interact I mean access a shared resource. (memory or other)
By distribute I mean distribute over multiple processors.
Isolated data is not a shared resource.
Synchronisation is normally used to provide consistency of the shared resource but not often used to provide overall ordering with regards to accessing it. Hence non determinism. If you can't tell which thread gets to access the shared resource and in which order, the program is no longer deterministic.
non-determinism of this type isn't inherently bad you just have to ensure that it does not matter. or force ordered access when that is possible (not always)
Think of a shared linked list as an example. The order of access by the reader and writer is non-deterministic and does not matter except when the list is empty or full when you have to impose and overall order. (writer first, reader first respectively)
No software is simple. Very little software can be analysed effectively. Unless you understand everything from the current machine state, all inputs and exactly what and when they happen, the hardware down to memory refresh, latency cache behaviour, OS behaviour, scheduling policy, other processes and states and their inputs, in addition to your software. It is complex, there is no simple software any more. Even if you claim that that is deterministic then you can still become unstuck if you have multiple physical processors and get non-deterministic behaviour. Note that this has little to do with most issues people have when they claim a computer does such-and-such arbitrarily.
If you have more then one thread running and they interact you no longer necessarily have a deterministic system. If you distribute it it gets even worse. Even in small embedded realtime systems you can get non-deterministic behaviour.
I had not even thought about it. Thinking about it I do use the hand brake quite often. So yes some people with manual gearboxes do use it. Most of the world do not use automatic gearbox's
12 cylinder 24 litre pistol engines where more powerful. I love the tech though.
Did you read that? Night vision gear. Yes I suppose they can land with that equipment. It is not normal kit though
It is tiny. Know-one knows exactly where it is. Yes NASA did know where it went but not with enough accuracy to tell where it is now. 40 years is a long time to modify and orbit.
I was wondering about that as I had not heard of commercial hardware that could handle anywhere near that bandwidth.If you push it into restricted frequencies it is possible but not anything cheap that I know off. I can get you gigabit wireless links but it is not simple and very much not cheap. Range limited and mostly line of sight. I suppose tech changes so it may be possible.
He plead guilt in court. Perhaps he did do what the prosecution claimed he did? If he had any possible defence he may have taken it. This is not the US so freedom of speech is not quite the same here. You can be prosecuted for writing nasty letters to people. Why is it hard to understand that the same laws will apply to something you do on the internet.
I think the poster did not mean civil offence. There are three kinds of criminal offence in the UK. And the court procedures are different. Summary - magistrate. Inditable - Crown court (jury). Triable either way - you get the choice of magistrates or jury trial.
Not all criminal offences are recorded on your criminal record and not all are declarable. Speeding tickets are (as far as I know) not recorded apart from on you license.
My mother 70 ish now shows allergic reactions to pretty much every test known to man. The only things she is actually allergic to are bee stings and penicillin. And she has ended up in hospital because of bee stings and was already in hospital (different reason) when she had a massive reaction to penicillin (not other antibiotics though) She has to wear a medic aid bracelet warning about penicillin now.
So I don't have much confidence in those tests. If they show positive then your body is overreacting. but not necessarily in a way that is detrimental.
"The whole climate change discussion will go the way of acid rain, ozone layer hole, acid ocean"
So you agree that laws mandating behaviour should be used to limit CO2 emissions to mitigate the effects on the atmosphere. All the other issues you raised had their effects reduced by similar laws an restrictions (sulphur filters on coal fired power station, Banning CFC use in aerosols and cooling systems.
The NHS has quite a wide range of hearing aids that they can prescribe depending on the type of hearing loss you have. You can buy privately as well and still be entitled to free ones from the NHS. They also provide batteries.
In the UK privately purchased hearing aids cost between £500 and £4000.
If it was GPL they would not have touched the code. So you wuld have not just have fragmented versions but entirely written from scratch versions.
I prefer BSD or Apache style licences. But I understand the goal of GPL. It just went to far. LGPL is a good level but it is so poorly defined that any company lawyer looks at it and they start pulling their hair out and shout NO.
Oh you had the joy of installing from 70 odd floppy disks too. I'm glad I was not the only one to suffer. Enough to make me buy a 2x CD rom :) for £220. It did come with an interface card though. My sound card did not support it.
Perhaps you did not realise but bits of BART are underground. There is no frequency allocation. Just repeaters that they own. I fear that they are not obliged to offer service.
It is empirical science. They do not have to have a reason for it. They just have to rule out reasons that they could be due to faulty machinery. And that it does not fit current models. After that it becomes a question of "how an this be explained"
Most new advances in science start with someone saying "WTF?"
And one of the earliest was a nuke that managed to destroy one of the first coms satellites. It made me chuckle when I found that out.
The economic effects were far and wide. In the UK we had radioactive sheep because of Chernobyl. Not really but farmers had to put up with massive expense because of it.
Perhaps for use at home voice recognition would work. but in an office? Loads of people talking at their computers? A very noisy environment. Are you sure that is a good idea?
It is useful to correct for barrel distortion no matter how far you fire. Do you think that a minor defect would not throw artillery far off target?
No problem. I was just trying to explain some of the technology being used for long range targets.
Did the Russians develop a gun launched missile? Cool idea but it would probably kill the operator. There were enough problems with the development of the star streak missile. It requires small motor to get it out of the tube without hurting the operator. Then a second to get it up to speed. It would burn the poor bugger who fired it if not. It is a line of sight weapon. Short range of about 7 km with the mk2. Designed for hitting aircraft but I think there have been successes against ground targets.
A .50 bullet should provide a kill no matter where you hit them. It is a big round and hitting them anywhere will cause them to have a really bad day.
1.5 K but still impressive! A very long distance. Not the longest recorded shot but the longest for a 7.62 calibre rifle.
8120 feet must be a new record. That is almost 2.5 K. an extremely long way. How some one can hit a target at that distance I do not know.
I know that I could not consistently hit a barn door at 2.5 kilometres let alone 2.3. Doing it multiple times... shockingly good! I do not think that killing people is a good idea but they both did the job asked of them and excelled at it.