In short, it never ceases to amaze me how humanity devolves during disasters and make a bad situation even worse.
Do you mean 'humanity' or 'americans'?
For some reason I don't remember such reports after the indian ocean tsunami. This could be a result of skewed reporting, but I don't see any reason why reporters should have this specific bias.
No need to splice individual wires: just press insulation-displacement connectors onto the ends of the ribbon cable at an offset of one wire and connect them together. Cut the two outermost wires with a sharp knife and attach them to the signal source.
How many other ways are there to do the same thing? Clean, I think not.
Anders Hejlsberg is no Guido Van Rossum and Microsoft doesn't have the luxury of carefully evolving language design over a period of 15 years.
Syntactic sugar naturally means TMTOWDI but it's not always evil. In this case I think it's justified. 1000% more justified than the monstrosity that C++ has become.
Damn it. I find myself defending Microsoft too much lately... It doesn't mean I suddenly started to like their business strategy, but there's less and less to complain about from a quality point of view.
Why, oh why must language inventors continue to add every possible concept to their pet project? Must every language try to be everything to everyone?
This isn't just a random heap of features. They all combine to create the query syntax which can run in-memory as C# code or be translated to external query languages such as SQL or XQuery and sent to a remote server for execution.
No programming language is suited to all applications;
But C# with embedded query syntax is an elegant solution to bridging high level languages and databases. This answers a very real and very pressing need in the industry.
Certainly it has some very good ideas -- but it lacks any sense of cohesion in design or intent, and it's ties to Microsoft make me leary of using it for long-term coding projects.
As an open-source I really hate to say this but...
This is a terrific example of honest-to-god innovation from Microsoft.
Yes, I know, the building blocks have been available in some form or another in many other platforms. But so far nobody has managed to bring all of this together so elegantly.
The features are not just a random heap of syntactic sugar. They combine to create the query syntax (using lambdas) which can be either executed directly in C# (with the help of external methods) or be available as a runtime data structure (shades of lisp) that can be translated dynamically to an SQL or XQuery and sent to a remote server for execution. The type inference ensures that the query syntax is not littered by type declarations yet remains typesafe.
Nice work, Anders. I guess the Comega team deserves much of the credit, but I have the feeling it was Anders who brought it all together into a clean and not too "academically smelling" framework.
"Rockoons" (rockets launched from balloons) have been tried but only for very small rockets. None of them orbital so far.
Balloons are pretty much at the mercy of the wind. You can't choose your launch spot for range safety and precise orbital insertion. For large rockets ground handling and launching of such huge balloons is difficult, dangerous and very sensitive to weather. Landing back after a scrubbed launch is virtually impossible.
These big rockets have been Elon Musk's goal all along. That's why he didn't use air launch.
Air launching has many advantages: lower atmospheric pressure improves the efficiency of engines, reduces air drag losses, greatly reduces dynamic loads, allowing the use of lighter structures. Perhaps most importantly, air launching can be done over the ocean without expensive range fees - and range delays like SpaceX is currently experiencing.
But air launch does not easily scale to large sizes. For really large rockets you have to launch from the ground.
Elon eventually plans to build a Saturn-V class launcher for for manned missions to Mars. It may seem premature when they haven't launched Falcon 1 yet, but so far they seem to be doing the right things.
It will be fun to read their prospectus
on
TrollTech to IPO?
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· Score: 1
Companies going public are required to list all the dangers to their business model and all possible things that could go wrong as part of their full disclosure to potential investors.
Reading these lists can be quite an educational experience.
In other words, NASA did all the research back in 1965, and the private space ventures sat on their asses for 40 years?
When the government as your taxpayer-subsidized competition would you invest in the space business?
I'm sure NASA would be more than happy to put itself out of the launch business. Scientists are happy working on the leading edges of research, not shuttling astronauts into LEO.
History says otherwise. NASA has fought hard to keep its monopoly in space, aided by congressmen representing the districts where most of NASA pork is distributed. The closest thing to "private" space industry was defense contractors who really liked the "cost plus" system where they got payed for development rather than results and could basically charge the government more whenever they had cost overruns. Evidence a string of at least seven(!) failed replacements for the space shuttle over they years, all of them promising "radically reduced launch costs" and ending up costing the taxpayers billions.
Your reaction is understandable, though. Most people don't know history well enough.
Well, without that "waste of money", SS1 would still be nothing but a glimmer in Burt Rutans eye.
Agreed. NASA has blazed the trail that private space entrepreneurs are walking now. None of this would have been possible without the knowledge that NASA had to learn the hard way using lots of taxpayer dollars.
But virtually all the atmospheric, space and rocket propulsion knowledge which was required for the design and construction of SpaceShip1, the SpaceX Falcon 1, the t/Space launcher and other private space vehicles in the works was acquired before 1965.
It's a cheap and scaleable method to defeat such algorithms. There will always be enough humans willing to do this for very little reward (some free pics).
The environmental impact of the launch itself is utterly insignificant compared to the total environmental footprint of the industry directly and indirectly supporting it.
The most salient fact? About 10,000 people per day were dying per day in the Pacific theatre, mostly civilians in Japanese-occupied countries. Any alternative to the bombs that would have caused a one month delay would have wound up with more dead than the bombs themselves.
Consider what it means: that humans are capable of getting themselves into siturations where dropping a single instrument capable of killing some 100,000 civilians and causing long term radiation damage can actually be the right thing to do.
To make a reliable two-stage reusable launcher, the first stage has to achieve some nasty speeds and some serious height (say Mach-3-6, 30-50km).
Who says?
Len Cormier is working on a very realistic concept where the first stage will climb to around 30 km but will do so at subsonic speeds. It will have a very large wing area compared to its weight to be able to generate lift at such low speed and thin air. The wings will be a fabric-covered frame and the whole thing will look more-or-less like a giant ultralight. Unlike conventional aircraft which are optimized for cruising at maximum fuel efficiency this thing is designed to be simple and climb rapidly. It turns out that the best engine for it is a rocket because of its high thrust to weight ratio and ability to work efficiently at high altitude. Yes, a subsonic rocket-powered giant hang glider. It sounds weird but it makes perfect sense from an engineering point of view and is pretty low tech in comparison to spacecraft and conventional aircraft.
The second stage can use efficient high expansion ratio engines that can't work at sea level. The second stage does not need to suffer a rough and fast ride through the dense atmosphere (max Q). A short and chubby body can be used, which is much better for containing large amounts of fuel in a lightweight envelope than a skinny cylinder. A large empty tub also has a much easier time on reentry - temperatures are much lower when the mass divided by cross section is lower, reducing TPS weight and allowing use of materials less fragile and with far lower maintenance than shuttle tiles.
These things make a big difference. Although the second stage needs almost as much performance as a full SSTO it can be much easier to build when it starts at 30km altitude.
.. space planes? Take off and land just like an airplane. Whatever happened to that idea?
The unforgiving results of the rocket equation when applied to the orbital velocity (as determined by the Earth's mass and radius) and the chemical energy available per lb of propellant. They all combine to make the task just barely possible. You get the impression that that some god wanted us to be able to get to space - but that it should be a serious challenge.
When your spacecraft must be made almost entirely of propellant it wants to be as close as possible to a sphere: lots of internal volume for propellant, minimum weight of the enclosing envelope. Airplanes really don't want to be anything like a sphere. They like un-spherelike protrusions known as wings. These weigh a lot, especially when you need to cover that much surface area with a heavy thermal protection system.
Landing with wings or lifting bodies can make sense in some circumstances but taking off with wings is ridiculous. The weight of the spacecraft at launch is much higher. If you size your wings for take-off weight you will pay the penalty of those big wings all the way to orbit and back (if it can even make it to orbit).
Just because the idea is intuitively appealing doesn't mean that it makes sense from an engineering point of view.
AFAIK, US spacecraft stopped being 5psia 100% oxygen
True, except for the really small class of spacecraft known as a "space suit". They still use low pressure pure oxygen because higher internal pressure would make them too rigid.
Before moving from high pressure oxygen+nitrogen to low pressure oxygen the astronauts need a lengthy pre-breathe to get the nitrogen out of their systems. If they don't do that they'll get the bends, just like divers that go up too quickly.
I'm sorry, but what part of saying "we were wrong" do you find pretentious?
Our experience with Microsoft's Passport is instructive in this regard.... it did not make sense to most non-MSN sites for Microsoft to be involved in their customer relationships... as a result, Passport failed in its mission...
Nope. Not a maser. Technically, it's no different from the transmitter element of a radar. What makes it "special" is the specific combination of frequency and pulse width, optimized to maximize pain with minimum energy.
Great heavens, that's a laser!
Yes Dr. Scott, a laser capable of emitting a beam of pure antimatter.
Slashdot Mirror
In short, it never ceases to amaze me how humanity devolves during disasters and make a bad situation even worse.
Do you mean 'humanity' or 'americans'?
For some reason I don't remember such reports after the indian ocean tsunami. This could be a result of skewed reporting, but I don't see any reason why reporters should have this specific bias.
No need to splice individual wires: just press insulation-displacement connectors onto the ends of the ribbon cable at an offset of one wire and connect them together. Cut the two outermost wires with a sharp knife and attach them to the signal source.
How many other ways are there to do the same thing? Clean, I think not.
Anders Hejlsberg is no Guido Van Rossum and Microsoft doesn't have the luxury of carefully evolving language design over a period of 15 years.
Syntactic sugar naturally means TMTOWDI but it's not always evil. In this case I think it's justified. 1000% more justified than the monstrosity that C++ has become.
Damn it. I find myself defending Microsoft too much lately... It doesn't mean I suddenly started to like their business strategy, but there's less and less to complain about from a quality point of view.
Why, oh why must language inventors continue to add every possible concept to their pet project? Must every language try to be everything to everyone?
This isn't just a random heap of features. They all combine to create the query syntax which can run in-memory as C# code or be translated to external query languages such as SQL or XQuery and sent to a remote server for execution.
No programming language is suited to all applications;
But C# with embedded query syntax is an elegant solution to bridging high level languages and databases. This answers a very real and very pressing need in the industry.
Certainly it has some very good ideas -- but it lacks any sense of cohesion in design or intent, and it's ties to Microsoft make me leary of using it for long-term coding projects.
It only looks that way if you don't RTFA...
As an open-source I really hate to say this but...
This is a terrific example of honest-to-god innovation from Microsoft.
Yes, I know, the building blocks have been available in some form or another in many other platforms. But so far nobody has managed to bring all of this together so elegantly.
The features are not just a random heap of syntactic sugar. They combine to create the query syntax (using lambdas) which can be either executed directly in C# (with the help of external methods) or be available as a runtime data structure (shades of lisp) that can be translated dynamically to an SQL or XQuery and sent to a remote server for execution. The type inference ensures that the query syntax is not littered by type declarations yet remains typesafe.
Nice work, Anders. I guess the Comega team deserves much of the credit, but I have the feeling it was Anders who brought it all together into a clean and not too "academically smelling" framework.
"Rockoons" (rockets launched from balloons) have been tried but only for very small rockets. None of them orbital so far.
Balloons are pretty much at the mercy of the wind. You can't choose your launch spot for range safety and precise orbital insertion. For large rockets ground handling and launching of such huge balloons is difficult, dangerous and very sensitive to weather. Landing back after a scrubbed launch is virtually impossible.
* Electric power - 60 MW
* Heat output - 50 Gcal/h
I find it suspicous that the electric power is 3% higher than heat output.
Google calculator calculation
These big rockets have been Elon Musk's goal all along. That's why he didn't use air launch.
Air launching has many advantages: lower atmospheric pressure improves the efficiency of engines, reduces air drag losses, greatly reduces dynamic loads, allowing the use of lighter structures. Perhaps most importantly, air launching can be done over the ocean without expensive range fees - and range delays like SpaceX is currently experiencing.
But air launch does not easily scale to large sizes. For really large rockets you have to launch from the ground.
Elon eventually plans to build a Saturn-V class launcher for for manned missions to Mars. It may seem premature when they haven't launched Falcon 1 yet, but so far they seem to be doing the right things.
We just wonder when private industry will put Nasa out of the game.
Did anyone else here first read that phrase as "put NASA out of its misery"?
Oddly, when I googled the phrase "put * out of its misery" the first result was about... NASA.
Companies going public are required to list all the dangers to their business model and all possible things that could go wrong as part of their full disclosure to potential investors.
Reading these lists can be quite an educational experience.
In other words, NASA did all the research back in 1965, and the private space ventures sat on their asses for 40 years?
When the government as your taxpayer-subsidized competition would you invest in the space business?
I'm sure NASA would be more than happy to put itself out of the launch business. Scientists are happy working on the leading edges of research, not shuttling astronauts into LEO.
History says otherwise. NASA has fought hard to keep its monopoly in space, aided by congressmen representing the districts where most of NASA pork is distributed. The closest thing to "private" space industry was defense contractors who really liked the "cost plus" system where they got payed for development rather than results and could basically charge the government more whenever they had cost overruns. Evidence a string of at least seven(!) failed replacements for the space shuttle over they years, all of them promising "radically reduced launch costs" and ending up costing the taxpayers billions.
Your reaction is understandable, though. Most people don't know history well enough.
Well, without that "waste of money", SS1 would still be nothing but a glimmer in Burt Rutans eye.
Agreed. NASA has blazed the trail that private space entrepreneurs are walking now. None of this would have been possible without the knowledge that NASA had to learn the hard way using lots of taxpayer dollars.
But virtually all the atmospheric, space and rocket propulsion knowledge which was required for the design and construction of SpaceShip1, the SpaceX Falcon 1, the t/Space launcher and other private space vehicles in the works was acquired before 1965.
It's a cheap and scaleable method to defeat such algorithms. There will always be enough humans willing to do this for very little reward (some free pics).
Spammers are already promoting a product called "The Antidote" supposedly produced from crocodile blood. With these news I think it will get worse.
Here is the FDA's warning.
The worst thing about it is to realize that some desperate people are actually falling for this scam.
The environmental impact of the launch itself is utterly insignificant compared to the total environmental footprint of the industry directly and indirectly supporting it.
There are other alternatives. You can also be:
The most salient fact? About 10,000 people per day were dying per day in the Pacific theatre, mostly civilians in Japanese-occupied countries. Any alternative to the bombs that would have caused a one month delay would have wound up with more dead than the bombs themselves.
Consider what it means: that humans are capable of getting themselves into siturations where dropping a single instrument capable of killing some 100,000 civilians and causing long term radiation damage can actually be the right thing to do.
To make a reliable two-stage reusable launcher, the first stage has to achieve some nasty speeds and some serious height (say Mach-3-6, 30-50km).
Who says?
Len Cormier is working on a very realistic concept where the first stage will climb to around 30 km but will do so at subsonic speeds. It will have a very large wing area compared to its weight to be able to generate lift at such low speed and thin air. The wings will be a fabric-covered frame and the whole thing will look more-or-less like a giant ultralight. Unlike conventional aircraft which are optimized for cruising at maximum fuel efficiency this thing is designed to be simple and climb rapidly. It turns out that the best engine for it is a rocket because of its high thrust to weight ratio and ability to work efficiently at high altitude. Yes, a subsonic rocket-powered giant hang glider. It sounds weird but it makes perfect sense from an engineering point of view and is pretty low tech in comparison to spacecraft and conventional aircraft.
The second stage can use efficient high expansion ratio engines that can't work at sea level. The second stage does not need to suffer a rough and fast ride through the dense atmosphere (max Q). A short and chubby body can be used, which is much better for containing large amounts of fuel in a lightweight envelope than a skinny cylinder. A large empty tub also has a much easier time on reentry - temperatures are much lower when the mass divided by cross section is lower, reducing TPS weight and allowing use of materials less fragile and with far lower maintenance than shuttle tiles.
These things make a big difference. Although the second stage needs almost as much performance as a full SSTO it can be much easier to build when it starts at 30km altitude.
.. space planes? Take off and land just like an airplane. Whatever happened to that idea?
The unforgiving results of the rocket equation when applied to the orbital velocity (as determined by the Earth's mass and radius) and the chemical energy available per lb of propellant. They all combine to make the task just barely possible. You get the impression that that some god wanted us to be able to get to space - but that it should be a serious challenge.
When your spacecraft must be made almost entirely of propellant it wants to be as close as possible to a sphere: lots of internal volume for propellant, minimum weight of the enclosing envelope. Airplanes really don't want to be anything like a sphere. They like un-spherelike protrusions known as wings. These weigh a lot, especially when you need to cover that much surface area with a heavy thermal protection system.
Landing with wings or lifting bodies can make sense in some circumstances but taking off with wings is ridiculous. The weight of the spacecraft at launch is much higher. If you size your wings for take-off weight you will pay the penalty of those big wings all the way to orbit and back (if it can even make it to orbit).
Just because the idea is intuitively appealing doesn't mean that it makes sense from an engineering point of view.
Weight happens.
In a galaxy far, far away...
...did not want to get into a position where the agency had to rely on commercial contracts to carry out the vision
Translation:
Space entrepreneurs! I'd really like to be a customer for your services, but just in case, I'll also be your government-subsidized competition.
P.S. Tell that to your investors. I'm sure they'll get reall excited!
AFAIK, US spacecraft stopped being 5psia 100% oxygen
True, except for the really small class of spacecraft known as a "space suit". They still use low pressure pure oxygen because higher internal pressure would make them too rigid.
Before moving from high pressure oxygen+nitrogen to low pressure oxygen the astronauts need a lengthy pre-breathe to get the nitrogen out of their systems. If they don't do that they'll get the bends, just like divers that go up too quickly.
Many hosting providers use FreeBSD and swear by it. I don't expect Pair networks, for example to change from FreeBSD anytime soon.
I'm sorry, but what part of saying "we were wrong" do you find pretentious?