Increased complexity means increased probability of failure, unless you get things right by removing single points of failure. This takes time and the earliest versions of OpenVMS clustering had a lot of problems. However by VAX/VMS V3.1, the system seemed to go quite nicely.
In the older days, Digital published source listings so I had a chane to see what went on. Clustering is so deeply bound within VMS that they don't ship an exec without that facility. If clustering is off, the code is still there, just disabled in a few key places.
Clustered VMS systems still do useful things, like running financial trading systems. Bits fail and apart from a pause whilst the locks fail over, nothing gets lost and production continues.
It is a shame some of the other cluster vendors didn't think this out. Maybe HP will now they have the source code but with their current anti-Engineer bent, I don't think so.
Not quite, what about IMAX? That is still in a 70mmm flipped format (the thing runs and is projected horizontally). However I don't think too many people would be copying those.
If you don't have your own copy of the software, it is quit easy for the vendor to force an updated EULA on their customers. At this point you may find that your next operation will not proceed without you either explicitly or implicitly (worse) accepting the ammended terms and conditions.
In the case of MS, the ammended EULA is forced upon you when you download updates.
Yes, I started a looonnnggg time ago with VMS clusters so I'm aware of this little problem (called a partitioned cluster). Thius is generally solved by a quorum which is a count on the minumum number of systems allowed to participate in the cluster.The quorum figure and the number of votes per machine can, of course, be tweaked dynamically.
For the flight control systems it is somewhat easier as they machines are not in a cluster. They just effect their output through a checking mechanism (a simple but reliable bit of hard-wired logic) that says if 1 machine doesn't agree with the other two, it is ignored (and I believe reset, just in case).
On the principle that the decryption s/w will have to be at the theatre and that somewhere along the line someone has to have the keys. It doesn't particularly work with sat tv so why would it work for films via sat?
The current ATC system is advisory, the pilot has ultimate control but the pilot submits flight plans in advance.
Let us consider another way, increase the automation on the ground and let the pilot submit only a request to say they want to fly to B from A with a particular departure time slot. Given such things as a planes flying characteristics (speed, range, altitude ceiling) and the weather, it should be possible for ATC to create a route and to plan separations for other aircraft on the same route. Once in the air, ATC should be able to discuss progress with the plane's flight computer automatically and adjust routes accordingly in addition to collision avoidance.
NASA apparently has a project looking at something like this, but I don't see it getting into production for at least another ten years, probably more given the infighting involved with major FAA ATC modernisation schemes.
Seriously, it is already addressed by Airbus Industrie for their flight control systems. Build three computers, use two hardware technologied (Intel and Motorola) and have three teams develop different software from the same functional spec.
Add voting logic and you never get problems unless you go outside the functional spec defined envelope.
Fo real pilots, this can be rather constricting but for a reliable, automagically controlled personal planes, I guess it would be fine.
Re:Affordable personal flight is still just a drea
on
The Coming Air Age
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,blockquote>Oh, yeah: and the turbine is a lot more expensive. But that probably has more to do with General Electric's monopoly (or so I've heard) on the processes used to produce the fan blades than anything else.
Um, last I heard Rolls-Royce do a nice line in turbo-props (and they have a lot of patents themselves) but mostly for slightly larger aircraft (medium range commuter). I guess they would certainly come up with something if they saw a market.
The old discrete analogue avionics (say VOR Navs, etc) were very complicated and a bitch to maintain. Newer digital devices are a lot cheaper to build (even VOR, let alone GPS) and a cinch to maintain. Regrettably the lower costs are not always reflected in prices.
Mass-produced avionics would lead to further price reductions. Avionics pricing should certainly not be an issue. Incidetally, the reliability issue could be solved Airbus style with functionally identical technology produced by different hardware/software teams.
A 35mm print is big, 70mm is enormous (and very heavy). Sheer physical size makes borrowing difficult (but not impossible). A VHS cassette or DVD is small and can even be smuggled out in a pocket. OTOH, a removeable HD is extremely compact. If the theatre can read it then so could a better equipped illegal duplicating facility.
The film companies aren't going to send out an HD to a critic, or a buyer for a theatre/theatre-chain. They didn't send out prints, just VHS, or more recently DVD. Around major competition time (i.e., like the Acadamy Awards), the DVD screeners seem to go to everyone and their dog (as long as they are industry related).
Whilst in far places, I have even seen screeners broadcast with shit dubbing on TV and even shown by the national airline.
Um one of the biggest problems isn't the poor quality cam movies, it is the screeners. In former days the screeners were on VHS and generally were not particularly high quality to start with. Now the screeners are DVD and the rips (particularly to DIVX) are to be seen to be believed.
Where are those screeners coming from? Well, the film industry of course!!!!!
You have come up with the biggest real reason: the lower calorific value of ethanol/methanol against JP-1 (the normal Jet fuel) and certainly against the high-octane stuff loved by piston engined aircraft.
As regards the politics, well yes, the slash and burn land owners are behind this but it is always a good idea to have locally produced alternatives that don't require oodles of foreign exchange.
I used to work at a chemicals site. Any site is composed of a number of individual plants, usually treated as quasi-independent financial entities and they buy and sell each-other's products.
One of the most important products is steam (reactions are both exothermic (giving out heat) and endothermic (requiring heat). One plant may produce sufficient steam to provide heating for a number of other plants. There may be a net energy requirement for the site, but it is minimal compared with that of the endothermic plants taken individually.
As a final point, remember that ethanol has a lower boiling point than water so you are not going to lose a lot of water there. In fact liquid water is one of the waste products.
Unix, on the other hand, is incredibly well documented and all source is available. Uncertain how inodes are locked and released? No problem, there are many books and references to help you. If worst comes to worst, crack open the damn code.
This has nothing to do with open source,...
Something seems incompatible between these two statements. Not all systemns where you get source code are open source licensed, but the majority are. I love getting source code, and I use to look after Digital systems when they gave out the source listings on VMS. I couldn't easily make changes, but it made things a lot clearer.
I think someone else has mentioned it but one of the largest govt uses outside weapons simulation is weather. You just can't do medium to long range weather without a lot of computer power,
Oil companies like to have serious computer power too for prospecting and resevoir modelling.
In organic chemistry, you can do some serious molecular simulations ranging from pharmaceuticals through to the actions of enzymes and catalysts.
The fluidics side can even extend through to air-flow modeling (aircraft to cars) and combustion.
The best comment was when a pilot cracked a joke on going through security that taking nail clippers of him was kind of pointless if he is sitting at the controls. True, but security got upset and the pilot was fined/suspended.
As regards your soda can, there are still glasses on some flights (and some metal cutlery). Given the quantity of not so dilute Ethanol on board (frequently cited as a major fire risk), a couple of hundred grams in a few laptop batteries is neither near nor there.
I have a 15" screen on my notebook. I can't even open it properly when on coach and if the guy in front leans back w/o telling me properly - that can cause serious problems.
Lufthansa in business on intercontinental flights certainly do have 115vac outlets and the space to use a notebook.
Maybe the flight attendents do give the hand-jobs in first but they definitely do not in business. However the seat spacing is enough that you actually can get some sleep when you don't want to play with your notebook.
The self-destruct on the Black Arrow was just a small capsule of catalyst surrounding a detanator in the H2O2 tank. Blow this and the whole thing would go bang in a shower of steam!!!!
I don't know which catalyst was used, but I seem to remember that with pure H2O2, there was a lot of choice!
This is why I used the phrase "Life as we know it". We survive in an environment of relatively weak UV and very little cosmic rays or X-rays. Given our genetic structure, radiation is very damaging as it can break up genetic material. We already know that some creatures have better repair mechanisms than others, but in the Galatic core?
Perhaps some completely different form of life could evolve there with much better repair mechanisms (RAID-5 Genomes anybody).
It is considered unlikely that theer could be much likelihood of life as we know it anywhere near the Galactic core. The place has a black hole in it and lots of resulting radiation.
Managed to catch up with it on Star Movies out in India. It was good and I liked the representation of Ozzie politicians, particularly the then prime minister.
I would certainly that LOTR wasn't really mainstream Hollywood but unlike Pitch Black, the money came completely from the US (Give or take some tax breaks by the Kiwis, but that certainly used to be the same for Oz).
The other point is that a studio film often has better links into the distribution system. If it is really crap, they won't necessarily pick it up but they won't always look at an independent foreign production.
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In the older days, Digital published source listings so I had a chane to see what went on. Clustering is so deeply bound within VMS that they don't ship an exec without that facility. If clustering is off, the code is still there, just disabled in a few key places.
Clustered VMS systems still do useful things, like running financial trading systems. Bits fail and apart from a pause whilst the locks fail over, nothing gets lost and production continues.
It is a shame some of the other cluster vendors didn't think this out. Maybe HP will now they have the source code but with their current anti-Engineer bent, I don't think so.
Not quite, what about IMAX? That is still in a 70mmm flipped format (the thing runs and is projected horizontally). However I don't think too many people would be copying those.
In the case of MS, the ammended EULA is forced upon you when you download updates.
For the flight control systems it is somewhat easier as they machines are not in a cluster. They just effect their output through a checking mechanism (a simple but reliable bit of hard-wired logic) that says if 1 machine doesn't agree with the other two, it is ignored (and I believe reset, just in case).
On the principle that the decryption s/w will have to be at the theatre and that somewhere along the line someone has to have the keys. It doesn't particularly work with sat tv so why would it work for films via sat?
Let us consider another way, increase the automation on the ground and let the pilot submit only a request to say they want to fly to B from A with a particular departure time slot. Given such things as a planes flying characteristics (speed, range, altitude ceiling) and the weather, it should be possible for ATC to create a route and to plan separations for other aircraft on the same route. Once in the air, ATC should be able to discuss progress with the plane's flight computer automatically and adjust routes accordingly in addition to collision avoidance.
NASA apparently has a project looking at something like this, but I don't see it getting into production for at least another ten years, probably more given the infighting involved with major FAA ATC modernisation schemes.
Fo real pilots, this can be rather constricting but for a reliable, automagically controlled personal planes, I guess it would be fine.
Um, last I heard Rolls-Royce do a nice line in turbo-props (and they have a lot of patents themselves) but mostly for slightly larger aircraft (medium range commuter). I guess they would certainly come up with something if they saw a market.
Mass-produced avionics would lead to further price reductions. Avionics pricing should certainly not be an issue. Incidetally, the reliability issue could be solved Airbus style with functionally identical technology produced by different hardware/software teams.
The film companies aren't going to send out an HD to a critic, or a buyer for a theatre/theatre-chain. They didn't send out prints, just VHS, or more recently DVD. Around major competition time (i.e., like the Acadamy Awards), the DVD screeners seem to go to everyone and their dog (as long as they are industry related).
Whilst in far places, I have even seen screeners broadcast with shit dubbing on TV and even shown by the national airline.
Where are those screeners coming from? Well, the film industry of course!!!!!
Microsoft certainly do require a CD to install patches. This can be painful if you are on the road and the original CD isn't.
As regards the politics, well yes, the slash and burn land owners are behind this but it is always a good idea to have locally produced alternatives that don't require oodles of foreign exchange.
One of the most important products is steam (reactions are both exothermic (giving out heat) and endothermic (requiring heat). One plant may produce sufficient steam to provide heating for a number of other plants. There may be a net energy requirement for the site, but it is minimal compared with that of the endothermic plants taken individually.
As a final point, remember that ethanol has a lower boiling point than water so you are not going to lose a lot of water there. In fact liquid water is one of the waste products.
This has nothing to do with open source, ...
Something seems incompatible between these two statements. Not all systemns where you get source code are open source licensed, but the majority are. I love getting source code, and I use to look after Digital systems when they gave out the source listings on VMS. I couldn't easily make changes, but it made things a lot clearer.
Oil companies like to have serious computer power too for prospecting and resevoir modelling.
In organic chemistry, you can do some serious molecular simulations ranging from pharmaceuticals through to the actions of enzymes and catalysts.
The fluidics side can even extend through to air-flow modeling (aircraft to cars) and combustion.
Lufthansa provides 115vac for long haul in business.
In Brazil, which doesn't have any oil, they have been producing methanol from cane sugar amongst other things.
As regards your soda can, there are still glasses on some flights (and some metal cutlery). Given the quantity of not so dilute Ethanol on board (frequently cited as a major fire risk), a couple of hundred grams in a few laptop batteries is neither near nor there.
Lufthansa in business on intercontinental flights certainly do have 115vac outlets and the space to use a notebook.
Maybe the flight attendents do give the hand-jobs in first but they definitely do not in business. However the seat spacing is enough that you actually can get some sleep when you don't want to play with your notebook.
I don't know which catalyst was used, but I seem to remember that with pure H2O2, there was a lot of choice!
Perhaps some completely different form of life could evolve there with much better repair mechanisms (RAID-5 Genomes anybody).
It is considered unlikely that theer could be much likelihood of life as we know it anywhere near the Galactic core. The place has a black hole in it and lots of resulting radiation.
Managed to catch up with it on Star Movies out in India. It was good and I liked the representation of Ozzie politicians, particularly the then prime minister.
The other point is that a studio film often has better links into the distribution system. If it is really crap, they won't necessarily pick it up but they won't always look at an independent foreign production.