Some of the native hot-weather Texans at here at JSC are a little hesitant to take frigid assignments on Devon Island. Damn, wish I could get a chance to go....
At least you wouldn't need Fluoinert and liquid nitrogen to overclock your computers on Mars--just leave it outside;)
Step 1: encrypt the files you want to upload to a remote host using your favorite method. Step 2: login anonymously, upload to/pub/incoming or something similar. Step 3: ssh in, mv the files, chown/chgrp/chmod them, and decrypt them.
...users of anonymous ftp should have no illusions of privacy.
That is, unless you use a proxy.
Gah... *attempting to remove foot from moutn* Most people don't bother to use an anonymous proxy just to d/l stuff over ftp. Most ppl don't care, and most anon ftp sites are not the kind of places that would sell marketing data or otherwise do Bad Things.
I don't think anonymous ftp ought to be phased out. Since there's no password required, and since most ftp servers reserve the right to log all transactions, users of anonymous ftp should have no illusions of privacy.
Imagine if Walnut Creek shut down their server and said "Sorry folks! No more unencrypted ftp. We only allow secure logins." For truly anonymous ftp, you have to cater to the lowest common demoninator.
OTOH, telnet, rlogin, et.al. are evil and should have been wiped out long ago. Go ssh!:)
Perhaps skip the traditional blade, and put removable CBN coated cutting units, instead (trouble is, how do you determine chip breaker geometry with a sword held by a dragonslayer ?)
ROFL. That's excellent. For once someone made a good techie-joke that's not computer/internet related.
Have you checked in Machinery's Handbook? First, you'd need to find some material properties for dragon flesh. I checked, but the closest thing were some tables entitled "Optimum Feedrates for Rough Machining of Low Carbon Dragon"
In fact, NASA has a US built backup module ready to go.
Yes, but that module, the Interim Control Module (ICM), does not provide any power. It will provide attitude control and reboost for the station until a more permanent solution is available.
"A more permanent solution" means a successful Service Module or perhaps the US Propulsion Module in a few years.
The US Prop Module is a planned addition to the station that will be coming up on flight 10A.1 sometime in mid 2003. Originally designed to use off-the-shelf space shuttle hardware, the PM turned out to be much more complicated.
The attitude control thrusters on the PM are mounted on the end of arms, but those arms get in the way when the Shuttle is trying to transfer cargo robotically. As a fix, they're designing the arms so they fold out of the way, but get this--the arm joints are only designed for 50 stow/unstow cycles in their operational life.
The PM used to have the ability to keep itself refuelled indefinately by siphoning off a little extra OMS propellant from every visting Shuttle. The prop transfer system "cost too much", so the current PM design "saves money" by not having it. Instead, the only way to refuel the damn thing is to fly a dedicated Shuttle mission to bring the old PM home and replace it with a brand new one full of propellant.
"Whenever possible, the Program shall strive to be penny-wise and pound-foolish" -- the ISS motto.
In order to get approval for the Zvezda/Service Module launch, Russia has had to jump through hoops. Last year their Proton rockets blew up a few times, causing Kazakhstan to ban further launches until they could fix the problem.
NASA also has imposed restriction that Russia successfully launch 2 other Protons before they go ahead with the Service Module.
The 12 June date is not solid. If all goes well that is the earliest window for launch. Note that the listed window runs from July 8-14. If they can't get the SM up by the 14th of July, the next launch opportunity won't be until early August. Here's a breakdown of near term Russian launches:
June 23: Russian Proton K-DM with the Intersputnik Express-3A communications satellite from Baikonur Cosmodrome, Kazakhstan. Launch Time 8:28 PM EDT (0028 GMT June 24).
No earlier than June: Ukranian Zenit-2 with a Russian Kosmos military spacecraft from Complex 45 at Baikonur Cosmodrome, Kazakhstan. Launch time TBA.
June 28: Russian Cosmos-3M with the Russian Nadezhda COSPAS-SARSAT military navigation satellite, the Tsinghua-1 satellite for China and the SNAP-1 nano-satellite for Great Britain from Plesetsk Cosmodrome, Russia. Launch Time TBA.
June 30: International Launch Services Proton (Block DM) with first Sirius communications satellite (formerly known as CD Radio) from Baikonur Cosmodrome, Kazakhstan. Launch time 6:08:47 PM EDT (2208:47 GMT).
No earlier than July 1: Russian Proton with a Geyser data relay satellite for the Russian Ministry of Defense from Baikonur Cosmodrome, Kazakhstan. Launch Time TBA.
July 12: Starsem Soyuz-Fregat with two Cluster-2 satellites (FM6 and FM7) from Complex 31 at Baikonur Cosmodrome, Kazakhstan. Launch Time TBD.
July 12: Russian Proton on ISS flight 1R with the Zvezda Service Module for the International Space Station from Baikonur Cosmodrome, Kazakhstan. Launch Time TBD. (Launch is scheduled between July 8 - 14).
That's something that still takes a bit more gut feeling and intuition than most mathematicians are comfortable with, but it's the kind of decisionmaking that engineers make all the time.
Geneticl Algorithms are pretty cool.. sort of what you're doing is defining n independent variables that each have a certain range. Then, you run a really big Monte Carlo simulation by picking random values for the inputs and crunching the numbers for lots and lots of cases.
The coolness of genetic algorithms, iirc, comes handy in when the math takes so long to perform that it doesn't make sense to cover then entire range of combinations. By hitting a few points here and there you can selectively home in on combination(s) of input variables that yeild the desired results.
the.cx TLD is for Christmas Island, a small Island in the Indian Ocean, just south of Java.
.cx domains are freely available and cheap. 20 UKP for the first year and 10 for every year afterwards. International TLD's are sort of fun, because you can make up nifty domain names like yes.no or eat.it;)
Re:Is part of the problem lack of machines?
on
New Mega Alphas
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· Score: 1
Tru-64 looks pretty interestic from what I've seen, too.
Our old crusty office file/web/junk/intranet Sparc-2 was recently replaced with a shiny new Compaq brand Alpha Box. The local Unix admin guru (a Sun dude) was faced with the dilemma of a really cool new box that couldn't run his fave *nix OS. He chose to go with Tru-64. So far things are going pretty well.
Warning! Warning Will Robinson, the Bogosity meter has pegged! "The Air Force wanted a mushroom cloud so large" . . . "if the bomb exploded on the edge of the moon, the mushroom cloud would be illuminated by the sun"
You need two things in order to get a mushroom cloud: an atmosphere and gravity. Mushroom clouds are driven by convection. Hot gas is more bouyant than the surrounding atmosphere and it rises.
Hot gas near the lunar surface would simply expand outwards radially into the surrouding vacuum. Sorry guys, no mushroom cloud.:)
This book ought to be required reading for everyone who comes to Slashdot. "Hot Air Rises and Heat Sinks: Everything You Know about Cooling Electronics is Wrong" is funny as hell. It also explains thermodynamics in understandable language and dispells plenty of awful thermo superstitions.
US GOVERNMENT COMPUTER This is a US Government computer. This system is for the use of authorized users only. By accessing and using ths computer system you are consenting to system monitoring, including the monitoring of keystrokes. Unauthorized use of, or access to, this computer may subject you to disciplinary action and criminal prosecution
That's what everybody gets on our office machines at the Johnson Space Center. Considering the enormous mountains of paperwork that people type up every day, I would hate to be the guy who reads the key logs.;-) Even if all they did was store the keystroke logs somewhere, it would be an enormous amount of useless data.
There are two GPS signals: the regular C/A-signal and the encrypted P-signal.
The C/A signal is easier to aquire and less precise. Standard positioning services data is accurate to within about 100 meters. IIRC, this is the signal that is degraded. They randomly skew the data so that your results are slightly off.
The encrypted P-signal uses more than just the standard GPS frequency. It provides precise positioning services is for military use only. Receiving and decoding the P-signal requires special hardware.
What I suspect this press release means is that the standard positioning services will no longer be intentionally degraded. The press release also mentions that they could begin re-degrading the signal at any time. It's even possible to deny GPS coverage on any arbitrary region of the globe, with minimal effects elsewhere.
I find it amusing that the Web Surfer and I-Opener appeal to us only because they are hackable, yet the manufacturers never intended for anyone to modify them. Perhaps someone will realize that there is a niche market for cheap hackable devices for folks to modify and use as they please.
As a long time BeOS supporter I was dissapointed when Be shifted focus to internet appliances. They keep saying that internet appliances will be the Next Big Thing(tm). I haven't seen any evidence to support that just yet.
The value in these small devices comes from being able to use the device in a flexible way. Palms are quite limited compared to a desktop PC yet they are immensely popular because they are so versatile.
I see potential with lightweight, portable, and cheap PC-based machines: mp3 servers, x-terminals, low cost notebooks, even wearable computers. Nobody really wants to buy an appliance that only has one use unless it's dirt cheap or insanely faster/better/easier than the PC alternative.
So, The conspiracy is unravelled! The real reason for the missing parts is those sneaky "NINJAS for te abolition of moderation".
Well mister ninja, you may have temporarily set back Boeing's plans, but did you know that those missing tanks were actually MAPLE SYRUP tanks, destined for use in the Maple syrup Pancake Logistics Module (MPLM)?
The MPLM is a sophisticated pressurised pancake container built by the Alenia Company in Italy. It's true! They are building three of them and naming them Leonardo, Raphael, and Donatello. (I dunno what happened to Michaelangelo).
Silly Italians think they're named after famous artists, but we PANCAKE engineers know that they're really NINJA TURTLES! Can you dig it?!
Heh, good one. Boeing happens to be the prime contractor for the *International* Space Station.
The rumour going around here regarding the Mars polar lander is that it got to within 1 foot of the ground just fine. There was supposed to be a cutoff switch built into each of the 3 legs that automatically killed the retro rockets upon contact with the ground, but during the software design phase someone accidentally disabled the cutoff switch. The rockets kept firing . . . the lander kept trying to `fly' while sitting on the ground . . . it kicked up a huge cloud of dirt (thus incapacitating itself with dust), or maybe skidded along the ground until it flipped over.
Nothing on the space station is very new, technologically. Been there, done that, got the t-shirt . . . now let's stop pissing around in low earth orbit and do something useful in space.
Jean-Loup's homepage says: From 1981 to 1989 I participated in the construction of code generators and real-time systems for the Ada language within Alsys (renamed first Thomson Software Products then Aonix). I was a member of the Ada language design team.
Ok, before anybody goes "eeeew, Ada!", let me say that it's impressive to see that Jean-Loup is has a long history of doing Important Things. Designing a language is certainly cool.
However, the infamous jargon has this to say about Ada: A Pascal-descended language that has been made mandatory for Department of Defense software projects by the Pentagon. Hackers are nearly unanimous in observing that, technically, it is precisely what one might expect given that kind of endorsement by fiat; designed by committee, crockish, difficult to use, and overall a disastrous, multi-billion-dollar boondoggle (one common description wss "The PL/I of the 1980s"). Hackers find Ada's exception-handling and inter-process communication features particularly hilarious. Ada Lovelace (the daughter of Lord Byron who became the world's first programmer while cooperating with Charles Babbage on the design of his mechanical computing engines in the mid-1800s) would almost certainly blanch at the use to which her name has latterly been put; the kindest thing that has been said about it is that there is probably a good small language screaming to get out from inside its vast, elephantine bulk.
I'm curious about Ada, yet completely ignorant (and thus neutral) regarding Ada. However there seem to be quite a few people out there who absolutely hate it. Could you enlighten us as to how you feel personally about the Ada programming language, or perhaps say a few words on behalf of Ada?
Yes. The Saturn V's F1 engines used liquid oxygen and plain old jet fuel (kerosene). It's almost the same fuel combination that the Beal rocket will use, except that LOX is cryogenic and hydrogen peroxide is a room-temperature liquid.
One of the big advantages of using cryogenic propellant is that it doubles as a coolant. All of the liquid oxygen flowing into the F1 engines of a Saturn V first passed through pipes that wrapped around the nozzle and combustion chamber . . . to keep it cool.
The F1 engines even went one step further and injected raw liquid oxygen along the boundary layer of the nozzle. That way, a narrow layer of very cold (but soon to be very hot) fluid shielded the nozzle from the hot exhaust gas.
Did you ever wonder why in some photos and movies, the exhaust plume from a Saturn V's first stage is _dark_ for a few feet as it exits the nozzle and then suddenly becomes brilliant? That's partially because of the cooling layer of cryogenic oxygen that gets injected into the boundary layer halfway down the exhaust nozzle. If you're ever in Huntsville or Houston, take a look at a real Saturn V. They're really awesome
Here's a listing of some of the propellants used in the first stages of various rockets: V2: LOX / alcohol X-15: LOX / ammonia Redstone: LOX / alcohol Atlas: LOX / kerosene Delta: LOX / kerosene Titan: nitrogen tetroxide / aerozine-50 Saturn: LOX / Kerosene Proton: nitrogen tetroxide / usymmetric dimethyl hydrazine Soyuz: LOX/ Kerosene Ariane 4: nitrogen tetroxide / unsymmetric dimehyl hydrazine Ariane 5: LOX / liquid hydrogen
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At least you wouldn't need Fluoinert and liquid nitrogen to overclock your computers on Mars--just leave it outside ;)
Step 1: encrypt the files you want to upload to a remote host using your favorite method. /pub/incoming or something similar.
Step 2: login anonymously, upload to
Step 3: ssh in, mv the files, chown/chgrp/chmod them, and decrypt them.
Nope. Nitrogen boils at 77 degrees Kelvin, or -196C.
The -190C quoted in the article is 83K.
That is, unless you use a proxy.
Gah... *attempting to remove foot from moutn* Most people don't bother to use an anonymous proxy just to d/l stuff over ftp. Most ppl don't care, and most anon ftp sites are not the kind of places that would sell marketing data or otherwise do Bad Things.
Imagine if Walnut Creek shut down their server and said "Sorry folks! No more unencrypted ftp. We only allow secure logins." For truly anonymous ftp, you have to cater to the lowest common demoninator.
OTOH, telnet, rlogin, et.al. are evil and should have been wiped out long ago. Go ssh! :)
ROFL. That's excellent. For once someone made a good techie-joke that's not computer/internet related.
Have you checked in Machinery's Handbook? First, you'd need to find some material properties for dragon flesh. I checked, but the closest thing were some tables entitled "Optimum Feedrates for Rough Machining of Low Carbon Dragon"
As for the Science Power Platform (SPP), NASA is still bookkeeping it in their plans but no one really expects it to be there in real life.
Yes, but that module, the Interim Control Module (ICM), does not provide any power. It will provide attitude control and reboost for the station until a more permanent solution is available.
"A more permanent solution" means a successful Service Module or perhaps the US Propulsion Module in a few years.
The US Prop Module is a planned addition to the station that will be coming up on flight 10A.1 sometime in mid 2003. Originally designed to use off-the-shelf space shuttle hardware, the PM turned out to be much more complicated.
The attitude control thrusters on the PM are mounted on the end of arms, but those arms get in the way when the Shuttle is trying to transfer cargo robotically. As a fix, they're designing the arms so they fold out of the way, but get this--the arm joints are only designed for 50 stow/unstow cycles in their operational life.
The PM used to have the ability to keep itself refuelled indefinately by siphoning off a little extra OMS propellant from every visting Shuttle. The prop transfer system "cost too much", so the current PM design "saves money" by not having it. Instead, the only way to refuel the damn thing is to fly a dedicated Shuttle mission to bring the old PM home and replace it with a brand new one full of propellant.
"Whenever possible, the Program shall strive to be penny-wise and pound-foolish" -- the ISS motto.
NASA also has imposed restriction that Russia successfully launch 2 other Protons before they go ahead with the Service Module.
The 12 June date is not solid. If all goes well that is the earliest window for launch. Note that the listed window runs from July 8-14. If they can't get the SM up by the 14th of July, the next launch opportunity won't be until early August. Here's a breakdown of near term Russian launches:
June 23: Russian Proton K-DM with the Intersputnik Express-3A communications satellite from Baikonur Cosmodrome, Kazakhstan. Launch Time 8:28 PM EDT (0028 GMT June 24).
No earlier than June: Ukranian Zenit-2 with a Russian Kosmos military spacecraft from Complex 45 at Baikonur Cosmodrome, Kazakhstan. Launch time TBA.
June 28: Russian Cosmos-3M with the Russian Nadezhda COSPAS-SARSAT military navigation satellite, the Tsinghua-1 satellite for China and the SNAP-1 nano-satellite for Great Britain from Plesetsk Cosmodrome, Russia. Launch Time TBA.
June 30: International Launch Services Proton (Block DM) with first Sirius communications satellite (formerly known as CD Radio) from Baikonur Cosmodrome, Kazakhstan. Launch time 6:08:47 PM EDT (2208:47 GMT).
No earlier than July 1: Russian Proton with a Geyser data relay satellite for the Russian Ministry of Defense from Baikonur Cosmodrome, Kazakhstan. Launch Time TBA.
July 12: Starsem Soyuz-Fregat with two Cluster-2 satellites (FM6 and FM7) from Complex 31 at Baikonur Cosmodrome, Kazakhstan. Launch Time TBD.
July 12: Russian Proton on ISS flight 1R with the Zvezda Service Module for the International Space Station from Baikonur Cosmodrome, Kazakhstan. Launch Time TBD. (Launch is scheduled between July 8 - 14).
That's something that still takes a bit more gut feeling and intuition than most mathematicians are comfortable with, but it's the kind of decisionmaking that engineers make all the time.
The coolness of genetic algorithms, iirc, comes handy in when the math takes so long to perform that it doesn't make sense to cover then entire range of combinations. By hitting a few points here and there you can selectively home in on combination(s) of input variables that yeild the desired results.
the .cx TLD is for Christmas Island, a small Island in the Indian Ocean, just south of Java.
.cx domains are freely available and cheap. 20 UKP for the first year and 10 for every year afterwards. International TLD's are sort of fun, because you can make up nifty domain names like yes.no or eat.it ;)
Our old crusty office file/web/junk/intranet Sparc-2 was recently replaced with a shiny new Compaq brand Alpha Box. The local Unix admin guru (a Sun dude) was faced with the dilemma of a really cool new box that couldn't run his fave *nix OS. He chose to go with Tru-64. So far things are going pretty well.
"Me spell chucker work great. Need Grandma chicken."
Sorry, I'm being sarcastic today.
Good point, Mr.P. Fortunately the qid=.... part of the link above is just a generic non-logged-in account.
From now on, I promise to only post links to Amazon.com using Kurt the Pope's id number. That way he'll get lots of nifty new books.
"The Air Force wanted a mushroom cloud so large" . . . "if the bomb exploded on the edge of the moon, the mushroom cloud would be illuminated by the sun"
You need two things in order to get a mushroom cloud: an atmosphere and gravity. Mushroom clouds are driven by convection. Hot gas is more bouyant than the surrounding atmosphere and it rises.
Hot gas near the lunar surface would simply expand outwards radially into the surrouding vacuum. Sorry guys, no mushroom cloud. :)
This book ought to be required reading for everyone who comes to Slashdot. "Hot Air Rises and Heat Sinks: Everything You Know about Cooling Electronics is Wrong" is funny as hell. It also explains thermodynamics in understandable language and dispells plenty of awful thermo superstitions.
This is a US Government computer. This system is for the use of authorized users only. By accessing and using ths computer system you are consenting to system monitoring, including the monitoring of keystrokes. Unauthorized use of, or access to, this computer may subject you to disciplinary action and criminal prosecution
That's what everybody gets on our office machines at the Johnson Space Center. Considering the enormous mountains of paperwork that people type up every day, I would hate to be the guy who reads the key logs. ;-) Even if all they did was store the keystroke logs somewhere, it would be an enormous amount of useless data.
The C/A signal is easier to aquire and less precise. Standard positioning services data is accurate to within about 100 meters. IIRC, this is the signal that is degraded. They randomly skew the data so that your results are slightly off.
The encrypted P-signal uses more than just the standard GPS frequency. It provides precise positioning services is for military use only. Receiving and decoding the P-signal requires special hardware.
What I suspect this press release means is that the standard positioning services will no longer be intentionally degraded. The press release also mentions that they could begin re-degrading the signal at any time. It's even possible to deny GPS coverage on any arbitrary region of the globe, with minimal effects elsewhere.
I find it amusing that the Web Surfer and I-Opener appeal to us only because they are hackable, yet the manufacturers never intended for anyone to modify them. Perhaps someone will realize that there is a niche market for cheap hackable devices for folks to modify and use as they please.
As a long time BeOS supporter I was dissapointed when Be shifted focus to internet appliances. They keep saying that internet appliances will be the Next Big Thing(tm). I haven't seen any evidence to support that just yet.
The value in these small devices comes from being able to use the device in a flexible way. Palms are quite limited compared to a desktop PC yet they are immensely popular because they are so versatile.
I see potential with lightweight, portable, and cheap PC-based machines: mp3 servers, x-terminals, low cost notebooks, even wearable computers. Nobody really wants to buy an appliance that only has one use unless it's dirt cheap or insanely faster/better/easier than the PC alternative.
I thought about that too, but Poe died in 1849. There were no typewriters in 1849.
The message as we see it now came from a printing press. It's easy to manually flip the type around on a printing press.
Well mister ninja, you may have temporarily set back Boeing's plans, but did you know that those missing tanks were actually MAPLE SYRUP tanks, destined for use in the Maple syrup Pancake Logistics Module (MPLM)?
The MPLM is a sophisticated pressurised pancake container built by the Alenia Company in Italy. It's true! They are building three of them and naming them Leonardo, Raphael, and Donatello. (I dunno what happened to Michaelangelo).
Silly Italians think they're named after famous artists, but we PANCAKE engineers know that they're really NINJA TURTLES! Can you dig it?!
The rumour going around here regarding the Mars polar lander is that it got to within 1 foot of the ground just fine. There was supposed to be a cutoff switch built into each of the 3 legs that automatically killed the retro rockets upon contact with the ground, but during the software design phase someone accidentally disabled the cutoff switch. The rockets kept firing . . . the lander kept trying to `fly' while sitting on the ground . . . it kicked up a huge cloud of dirt (thus incapacitating itself with dust), or maybe skidded along the ground until it flipped over.
Nothing on the space station is very new, technologically. Been there, done that, got the t-shirt . . . now let's stop pissing around in low earth orbit and do something useful in space.
What would be useful? How about
You are right. The fuels I listed are only for the first stages.
Ok, before anybody goes "eeeew, Ada!", let me say that it's impressive to see that Jean-Loup is has a long history of doing Important Things. Designing a language is certainly cool.
However, the infamous jargon has this to say about Ada:
A Pascal-descended language that has been made mandatory for Department of Defense software projects by the Pentagon. Hackers are nearly unanimous in observing that, technically, it is precisely what one might expect given that kind of endorsement by fiat; designed by committee, crockish, difficult to use, and overall a disastrous, multi-billion-dollar boondoggle (one common description wss "The PL/I of the 1980s"). Hackers find Ada's exception-handling and inter-process communication features particularly hilarious. Ada Lovelace (the daughter of Lord Byron who became the world's first programmer while cooperating with Charles Babbage on the design of his mechanical computing engines in the mid-1800s) would almost certainly blanch at the use to which her name has latterly been put; the kindest thing that has been said about it is that there is probably a good small language screaming to get out from inside its vast, elephantine bulk.
I'm curious about Ada, yet completely ignorant (and thus neutral) regarding Ada. However there seem to be quite a few people out there who absolutely hate it. Could you enlighten us as to how you feel personally about the Ada programming language, or perhaps say a few words on behalf of Ada?
One of the big advantages of using cryogenic propellant is that it doubles as a coolant. All of the liquid oxygen flowing into the F1 engines of a Saturn V first passed through pipes that wrapped around the nozzle and combustion chamber . . . to keep it cool.
The F1 engines even went one step further and injected raw liquid oxygen along the boundary layer of the nozzle. That way, a narrow layer of very cold (but soon to be very hot) fluid shielded the nozzle from the hot exhaust gas.
Did you ever wonder why in some photos and movies, the exhaust plume from a Saturn V's first stage is _dark_ for a few feet as it exits the nozzle and then suddenly becomes brilliant? That's partially because of the cooling layer of cryogenic oxygen that gets injected into the boundary layer halfway down the exhaust nozzle. If you're ever in Huntsville or Houston, take a look at a real Saturn V. They're really awesome
Here's a listing of some of the propellants used in the first stages of various rockets:
V2: LOX / alcohol
X-15: LOX / ammonia
Redstone: LOX / alcohol
Atlas: LOX / kerosene
Delta: LOX / kerosene
Titan: nitrogen tetroxide / aerozine-50
Saturn: LOX / Kerosene
Proton: nitrogen tetroxide / usymmetric dimethyl hydrazine
Soyuz: LOX/ Kerosene
Ariane 4: nitrogen tetroxide / unsymmetric dimehyl hydrazine
Ariane 5: LOX / liquid hydrogen