With OS X, to do that requires manual keyboard intervention in two different ways (Cmd+Tab to the app, Cmd+` to the appropriate window if necessary). A reasonably workaround to this (IMHO) would be for the app's Dock menu to appear if the cursor was held over the icon for long enough, and from there the object could be dragged to the appropriate window.
I agree that would be a nice addition, maybe make it like spring-loaded folders. If you drag over a dock item then the menu will pop up after a small delay, or you can hit the spacebar to make it open immediately. That would make drag-and-drop easier. Hmm, looks like I've got a suggestion to send to Apple's UI feedback!
The important thing is that Apple does take suggestions very seriously. They have made huge changes to MacOS X and applications simply because a bunch of people asked for them. Take Safari for example, Apple was pretty set on not having tabs in their web browser but it now looks like they are going to be part of the browser because so many people asked for it. The same thing goes for spring-loaded folders, the Apple menu, and a ton of other improvements. If you don't like something that Apple makes, send them a suggestion on how to improve it, they seem to be listening.
I can't see how a window could be "accidentally" moved completely off screen. I can see how it could be done programmatically by the application, or deliberately by the user - but not "accidentally".
Actually, I have seen this a lot. One of the guys that I work with has placed the taskbar at the top of his screen. What happens is that somehow a program manages to get a window's menubar underneath the taskbar and then the window can't be moved or its menus accessed. The cure is to hide the taskbar for a second and move the window down but it is a pain in the butt, especially since this person is pretty clueless on how to fool around with the taskbar.
Dragging and dropping content from one app to another involves... Cumbersome it may be, but it is infinitely better than the complete lack of equivalent functionality in OS X.
It's pretty easy to drag-and-drop from one app to another in MacOS X. Simply start to drag from one application, hit command-tab until the other application comes up, and then drop the material into the document. Works like a charm.
Dock vs Taskbar for preview icons to be useful, they have to be huge
That's what dock magnification is for. Set the magnification for max and you will get a pretty good idea what is going on in that window when you mouse over it in the dock. Not only that but the program itself can change its icon to represent what is going on. Take Mail for example, if there is mail for you then the icon for Mail will have a red badge on it with the number of messages that have not been read yet. This number does not need to be huge since it is a simple graphic and does not have so much clutter obfuscating it.
After switching from a 5-button mouse to a 1-button one recently, the only thing I've been sort of missing is the scroll wheel.
I totally agree. I think that a 1-button, scroll wheel mouse would be absolutely perfect. It actually feels easier for me to use the control-click rather than the second mouse button in order to get a contextual menu. All I really miss is the ease of a scroll wheel.
Honestly, with my left hand on the keyboard and my right hand on the mouse I can use 3 or 4 modifier keys in any combination with a mouse click to do all sorts of things. Want to copy a file? Option-drag the file. Want to make an alias (shortcut) of a file? Option-command drag the file. Select more than one item? Shift-click or option-click them. The possibilities are numerous.
Uranus's non-exponent (is that mantissa?) is 86.8, which should be 8.68, and the exponent be 25
Yeah, of course the mantissa (you were right about that) should be less than 10. The web site had the exponents of the measurements as the same magnitude because that makes comparison of each mantissa easier. That's better for a lay-person to compare the values here on Slashdot, but in a more technical forum I would keep to the rule of a mantissa being less than 10.
Sure, just count the rings in a few selected feet or so and then extrapolate. You may not get an exact number but then again you don't need to be exactly right, just within a acceptable level or uncertainty.
the half-life of radio-active Carbon is approximately 5,700 YEARS. After about 10 half-lives the aggragate properties of radioactive decay no long hold
Yes, I am a chemist and yes, I do know this. This is why I specfically said "Carbon dating and isotopic analysis". Isotopic analysis includes using other isotopes such as potassium-40, rubidium-87, uranium-235, and uranium 238. Using these isotopes you can get dating as far back as about 5 billion years, more than enough to date dinosaur fossils and asteroid fragments that caused the extinction level event.
Take a look at this site to understand more about isotopic analysis methods.
a GOOD day for the earth as it got a major influx of material and upped its accretion rate, helping out in the race to be the biggest object orbiting the sun, though it still trails several other bodies
Well, considering that the Earth tips the scales at 5.97x10^24 kg and that the next highest planet is Uranus at 86.8x10^24 kg, I'd say that the Earth doesn't have much of a chance. Oh well, at least we are ahead of Pluto, Mercury, Mars, and Venus.
how do they know that this *particular* asteroid wiped out most of the species on the planet 65 million years ago?
They can't be 100% absolutely positively certain, but they can get pretty close to certain. There are several ways to find out if a particular asteroid was the cause of a certain effect.
We can get fairly accurate dating of both the asteroid event and the extinction event. You can find out when the impact occurred by noting how deep the the impact site and the material ejected from it is buried and comparing it to the sedimentation rates in the area. You can also perform carbon dating or other isotopic analysis on material that was killed in the region of the event at the impact layer.
If the impact was large enough then the material that made up the asteroid should have been deposited around the world. Each asteroid has a "fingerprint" of different isotopes that is fairly unique, so the deposited layer can be identified as to which asteroid caused it. This means that there will be an identifiable layer of material in the arctic ice. Since each yearly layer has seasonal dark and light bands, just count the rings to find out how old the deposited layer is.
Dating the dinosaurs is also done pretty easily. Carbon dating and isotopic analysis can narrow down the date pretty well, as well as buried depth, sedimentation rates, and other geological identifiers. Finally, the layer that the dinosaur fossils are found in will have some of that isotopic "fingerprint" from the asteroid that impacted the Earth.
With this information you can narrow down both the impact date and the extinction dates to a narrow range. If those ranges overlap and the impact was large enough, you probably have the impact that caused the extinction. It turns out that there is probably the major impact in the Yucatan Peninsula and a few much more minor impacts that caused the extinction of the dinosaurs. We've known about this for years, but more evidence never hurts.
I tried and tried to get the floppy out but couldn't. I finally had to call up a mac friend and ask. The answer is so utterly counter-intuitive that I was shocked.
You mean it was counter-intuitive to select the disk and go to the menu marked "File" and use the "Eject" item (key combo: apple-E)? You could also have used the "Put Away" (key combo: apple-Y) item in the "Special" menu . Later on when contextual menus were available you could control-click on the disk and hit the "Eject Disk" item.
Dragging the disk to the trash was just one of several ways to eject a disk. Some may have been more intuitive than others but the quickest way was to drag it to the trash. Think of it as a power user shortcut, not the default action.
With MacOS X the trash icon becomes a disk eject icon when you start to drag a disk anywhere. When you hover over the eject icon it says Eject. So now you do not drag the disk to the trash, you drag it to the eject.
I click on a link that has a JavaScript command to open in a new window. Note that I never wanted it to open in a new window, the web designer decided that. So now I am suck with two open windows, one with five tabs, and one with one tab.
Even better would be to have the ability to kill that JavaScript command entirely and just have it act as a normal link. Nothing is more annoying than clicking on a link and having it open a window when you didn't want to. If I wanted a second window to open I would have command-clicked on the link. Actually the most annoying thing is when I DO command-click on that JavaScript link without realizing what it is and it causes a blank window to open.
Please web designers, do not mess with the UI of the browser. Let the user decide what action to take instead of "helping" them out.
the contents of a couple of D engines ground up and stuck in a steel pipe capped at both ends makes a fairly big bang.
So do the contents of a few boxes of matches, or maybe a bit of fertilizer and some diesel fuel, or even some finely powdered flour floating in air. You can make a bomb out of any number of common ingredients. The answer is not to choke off all possible sources of rapidly exothermic chemical reactions, but rather to find those that are collecting these compounds in large amounts. I have no problems with governments asking me what I'm doing with ton lots of fertilizer, but when they put up barriers for me obtaining a tiny 10 gram solid fuel rocket motor for a hobby, that is just going too far.
I decided against saying something terribly insightful about the "Microsoft Tax".
I *do* find it F*cking hillarious that you would buy and Apple notebook computer, and load linux onto it, and be just as happy.
OHMYGOD: Apple won't sell a laptop without an OS either. THE BASTARDS!...
You feel better about paying the "Apple Tax"?
I totally agree that either way you are paying for the operating system, whether it is Windows or MacOS. I think the difference is in the moral objection to the companies.
Microsoft is well known for being rabidly anti-Linux and anti-open-source. They have said many times that Linux must be crushed and that the GNU license is a viral license that is a plague upon the software development community. Paying a "tax" to them is akin to donating money to a company that wants to stamp out the Linux operating system you want to install on your notebook.
Apple has made great strides toward supporting open standards and open source. Yes, they are still a company that produces and uses a large amount of proprietary, closed-source software but they don't seem to have anything against using open-source if it fits the situation. They are out to make a profit like everyone else but they at least take a stab at being as non-evil about it as possible.
So, on the whole I'd rather pay the Apple tax verses paying the Microsoft tax. It's not really about the money spent, but rather is about who the money goes to in the end.
I don't know, when I saw the term "quantum chemist" I thought that maybe he was atom-sized and played golf with electrons. Either that or maybe he was stuck leaping through space in time...
I know, I know, quantum chemistry is a genuine branch of science. I'm a chemist myself but I still can't help getting that image of that tiny little chemist taking a nap inside the s1 orbital of a hydrogen atom.
Is anyone else having touble getting the 'Applications' menu to work? I can't get GIMP to start except by starting it from an xterm and I'd really like to be able to use the menu for it (and other applications).
If executing applications from Terminal instead of xterm you have to type "open-x11 program" instead of just the program name. If you are used to Fink and XDarwin this wasn't necessary. To get it back to the way things used to work, add "setenv DISPLAY:0.0" to your.tcshrc file.
So either set up the menu to use the command "open-x11 gimp" (no quotes), or change your.tcshrc file and you can then just put "gimp" as the command (again, no quotes).
...serve a web page to it that has a content margin set to -30 pixels. We've all done it before, right?
Sure we have. Of course we then CHECKED the web page in the browser we were coding to and found the mistake. Or at least we should have, if we were a corporation with the assets and resources of a company like Microsoft.
But then again, I guess Microsoft can't be bothered with checking for bugs before it releases anything, especially when if affects products other than theirs. They must have been more busy eliminating security holes in their own, bug-ridden servers.
i wonder why you didnt had pick up the british dictionaire? Its only 900 years older than the one you had pointed
Dictionary.com that was the first definition that fit? I just tried to visit the Oxford English Dictionary Online but what do you know, it's a subscription service. British English, American English, it doesn't matter to me which one I look it up on, but I will use the free service over the pay one any day.
Football means foot on ball -American Football its played mostly with the hands, -WorldWide Football its played mostly with the foot
If you want to really understand why it is called football, check out this encyclopedia.com article. Basically American Football and Soccer (another name for Worldwide Football) come from the same roots and are both entitled to the name football. This doesn't make either game any better or worse than the other and it is fine if Americans call their game football even if they can use their hands during play. Also, remember that in American Football you can use your feet at any time, using your hands is a personal choice.
Heh, I guess it is according to this definition. Hey, I don't make the definitions I just look them up.
Honestly if I had to define a ball in a sports context I would define it as a spherical or ellipsoidal object which is designed to be thrown, struck, carried, or otherwise propelled in accordance with the rules of the sport.
But that's just the way I see it, I'm sure that there are many people who would change it to just include spheres.
Since they don't use a ball and don't play with their feet
First of all, from the American Heritage Dictionary (by way of Dictionary.com):
Ball
2. Sports.
a. Any of various rounded, movable objects used in various athletic activities and games.
So a football is indeed, a ball.
Secondly you can use your feet at pretty much any time during play to move the football. Many times you can also use your hands or really any part of your body to move it. Given the choice between holding the ball and kicking it you will probably rather hold the ball rather than kick it but that doesn't stop you from doing either. In fact there are some times when you have to use your feet, such as kickoffs.
So the sport does have some right to be called football. It could more accurately be called "Foot and Hand Prolate Spheroid", but that's a lot more cumbersome and I don't think it will catch on.:)
The one thing I don't get is, why not just require registration in order to post?
The very act of requiring registration ends up cutting down the number of posts a web site receives. I know that I hardly ever post on a web site that requires registration, Slashdot is pretty much the exception for me. I wouldn't have even registered on Slashdot if it required me to put down easily identifiable personal information.
Even if the website in question did have people register, it would have needed a sure way to identify registrants, such as by credit card number. It said in the article that the troll's username was banned but the guy snuck back under other names. Unless they could find a sure way to identify the guy (such as Microsoft's Passport **shudder**), they couldn't stop the guy from posting.
It comes down to this: require people to totally identify themselves (thus causing them to ignore the site), or take the chance that you won't get trolled and leave the site open to all. Trolls are the ones that are driving stuff like Passport and national ID numbers, if people didn't abuse the privacy that certain forums provide then there wouldn't be a need to pin people down with big brother tactics.
The goal is to eject mass out of the rocket at the highest possible velocity. It doesn't matter whether it is steam or paper clips.
Right, and it would help to use a fuel which has a low specific heat (that is, it takes little energy to heat it up) and also which doesn't take a lot of energy to go through phase changes. For each phase change a substance goes through it soaks up energy which could be better used in propulsion.
Hydrogen is better than water because hydrogen dissociates into a vapor with very little energy, where water takes a lot of energy to turn into steam. Water also will soak up a lot of energy in heating (high specific heat) up to the temperatures generated in the nuclear reaction, whereas hydrogen does not need as much energy to get up to temperature. In other words, you get more thrust out of equal masses of hydrogen and water with the same energy put into them.
However, there are other factors to consider. The main advantage of water is that it is easy to find, easy to store and pump around, can be used as a moderator for the nuclear reaction, can be used as shielding for the astronauts, the astronauts can use as their drinking supply, and they can use it to produce their oxygen supply. Hydrogen is a total mess to handle, its only real advantage is that it is a bit more energy efficient as a reaction mass. Water is generally accepted as a very good reaction mass due to these factors. The usability of water will most likely far outweigh any benefits you would get from using hydrogen.
Most books and music that are published never get a lot of circulation and aren't valuable enough to be worth publishing over the long term. These works slowly degrade over time and become unavailable in the future. Will you be able to play the CD you buy today in 90+ years? No. So unless somebody makes an extroridnary effort to archive this material in the hope that EVENTUALLY it will become legal to copy it, much of it will cease to exist.
The Library of Congress is the nation's oldest federal cultural institution, and it serves as the research arm of Congress. It is also the largest library in the world, with more than 120 million items on approximately 530 miles of bookshelves. The collections include more than 18 million books, 2.5 million recordings, 12 million photographs, 4.5 million maps, and 54 million manuscripts.
The one I HATE in wondows is when they change the save action on you.
Exactly. If the options had been [Don't Save] [Save] then there would be very little confusion about what action is going to be taken.
One other cool idea in human interface design is to make the least destructive action the default action in any "dangerous" dialog box. For example:
Erase entire hard drive?
[[Cancel]] [Erase]
Yeah, it's a little pain to not have the [Erase] button highlighted automatically, but it's worth the safeguard considering you are talking about the potential loss of all of your data.
Slashdot Mirror
I agree that would be a nice addition, maybe make it like spring-loaded folders. If you drag over a dock item then the menu will pop up after a small delay, or you can hit the spacebar to make it open immediately. That would make drag-and-drop easier. Hmm, looks like I've got a suggestion to send to Apple's UI feedback!
The important thing is that Apple does take suggestions very seriously. They have made huge changes to MacOS X and applications simply because a bunch of people asked for them. Take Safari for example, Apple was pretty set on not having tabs in their web browser but it now looks like they are going to be part of the browser because so many people asked for it. The same thing goes for spring-loaded folders, the Apple menu, and a ton of other improvements. If you don't like something that Apple makes, send them a suggestion on how to improve it, they seem to be listening.
Actually, I have seen this a lot. One of the guys that I work with has placed the taskbar at the top of his screen. What happens is that somehow a program manages to get a window's menubar underneath the taskbar and then the window can't be moved or its menus accessed. The cure is to hide the taskbar for a second and move the window down but it is a pain in the butt, especially since this person is pretty clueless on how to fool around with the taskbar.
It's pretty easy to drag-and-drop from one app to another in MacOS X. Simply start to drag from one application, hit command-tab until the other application comes up, and then drop the material into the document. Works like a charm.
That's what dock magnification is for. Set the magnification for max and you will get a pretty good idea what is going on in that window when you mouse over it in the dock. Not only that but the program itself can change its icon to represent what is going on. Take Mail for example, if there is mail for you then the icon for Mail will have a red badge on it with the number of messages that have not been read yet. This number does not need to be huge since it is a simple graphic and does not have so much clutter obfuscating it.
I totally agree. I think that a 1-button, scroll wheel mouse would be absolutely perfect. It actually feels easier for me to use the control-click rather than the second mouse button in order to get a contextual menu. All I really miss is the ease of a scroll wheel.
Honestly, with my left hand on the keyboard and my right hand on the mouse I can use 3 or 4 modifier keys in any combination with a mouse click to do all sorts of things. Want to copy a file? Option-drag the file. Want to make an alias (shortcut) of a file? Option-command drag the file. Select more than one item? Shift-click or option-click them. The possibilities are numerous.
Yeah, of course the mantissa (you were right about that) should be less than 10. The web site had the exponents of the measurements as the same magnitude because that makes comparison of each mantissa easier. That's better for a lay-person to compare the values here on Slashdot, but in a more technical forum I would keep to the rule of a mantissa being less than 10.
Sure, just count the rings in a few selected feet or so and then extrapolate. You may not get an exact number but then again you don't need to be exactly right, just within a acceptable level or uncertainty.
Yes, I am a chemist and yes, I do know this. This is why I specfically said "Carbon dating and isotopic analysis ". Isotopic analysis includes using other isotopes such as potassium-40, rubidium-87, uranium-235, and uranium 238. Using these isotopes you can get dating as far back as about 5 billion years, more than enough to date dinosaur fossils and asteroid fragments that caused the extinction level event.
Take a look at this site to understand more about isotopic analysis methods.
Well, considering that the Earth tips the scales at 5.97x10^24 kg and that the next highest planet is Uranus at 86.8x10^24 kg, I'd say that the Earth doesn't have much of a chance. Oh well, at least we are ahead of Pluto, Mercury, Mars, and Venus.
(Information is found at The Planetary Fact Sheet - Metric, you can check out the US measures at The Planetary Fact Sheet - U.S..)
They can't be 100% absolutely positively certain, but they can get pretty close to certain. There are several ways to find out if a particular asteroid was the cause of a certain effect.
We can get fairly accurate dating of both the asteroid event and the extinction event. You can find out when the impact occurred by noting how deep the the impact site and the material ejected from it is buried and comparing it to the sedimentation rates in the area. You can also perform carbon dating or other isotopic analysis on material that was killed in the region of the event at the impact layer.
If the impact was large enough then the material that made up the asteroid should have been deposited around the world. Each asteroid has a "fingerprint" of different isotopes that is fairly unique, so the deposited layer can be identified as to which asteroid caused it. This means that there will be an identifiable layer of material in the arctic ice. Since each yearly layer has seasonal dark and light bands, just count the rings to find out how old the deposited layer is.
Dating the dinosaurs is also done pretty easily. Carbon dating and isotopic analysis can narrow down the date pretty well, as well as buried depth, sedimentation rates, and other geological identifiers. Finally, the layer that the dinosaur fossils are found in will have some of that isotopic "fingerprint" from the asteroid that impacted the Earth.
With this information you can narrow down both the impact date and the extinction dates to a narrow range. If those ranges overlap and the impact was large enough, you probably have the impact that caused the extinction. It turns out that there is probably the major impact in the Yucatan Peninsula and a few much more minor impacts that caused the extinction of the dinosaurs. We've known about this for years, but more evidence never hurts.
You mean it was counter-intuitive to select the disk and go to the menu marked "File" and use the "Eject" item (key combo: apple-E)? You could also have used the "Put Away" (key combo: apple-Y) item in the "Special" menu . Later on when contextual menus were available you could control-click on the disk and hit the "Eject Disk" item.
Dragging the disk to the trash was just one of several ways to eject a disk. Some may have been more intuitive than others but the quickest way was to drag it to the trash. Think of it as a power user shortcut, not the default action.
With MacOS X the trash icon becomes a disk eject icon when you start to drag a disk anywhere. When you hover over the eject icon it says Eject. So now you do not drag the disk to the trash, you drag it to the eject.
Even better would be to have the ability to kill that JavaScript command entirely and just have it act as a normal link. Nothing is more annoying than clicking on a link and having it open a window when you didn't want to. If I wanted a second window to open I would have command-clicked on the link. Actually the most annoying thing is when I DO command-click on that JavaScript link without realizing what it is and it causes a blank window to open.
Please web designers, do not mess with the UI of the browser. Let the user decide what action to take instead of "helping" them out.
So do the contents of a few boxes of matches, or maybe a bit of fertilizer and some diesel fuel, or even some finely powdered flour floating in air. You can make a bomb out of any number of common ingredients. The answer is not to choke off all possible sources of rapidly exothermic chemical reactions, but rather to find those that are collecting these compounds in large amounts. I have no problems with governments asking me what I'm doing with ton lots of fertilizer, but when they put up barriers for me obtaining a tiny 10 gram solid fuel rocket motor for a hobby, that is just going too far.
I totally agree that either way you are paying for the operating system, whether it is Windows or MacOS. I think the difference is in the moral objection to the companies.
Microsoft is well known for being rabidly anti-Linux and anti-open-source. They have said many times that Linux must be crushed and that the GNU license is a viral license that is a plague upon the software development community. Paying a "tax" to them is akin to donating money to a company that wants to stamp out the Linux operating system you want to install on your notebook.
Apple has made great strides toward supporting open standards and open source. Yes, they are still a company that produces and uses a large amount of proprietary, closed-source software but they don't seem to have anything against using open-source if it fits the situation. They are out to make a profit like everyone else but they at least take a stab at being as non-evil about it as possible.
So, on the whole I'd rather pay the Apple tax verses paying the Microsoft tax. It's not really about the money spent, but rather is about who the money goes to in the end.
Damn my too fast fingers, I of course meant the 1s orbital. That's what comes of posting quickly and not previewing what you wrote. Oh well...
I don't know, when I saw the term "quantum chemist" I thought that maybe he was atom-sized and played golf with electrons. Either that or maybe he was stuck leaping through space in time...
I know, I know, quantum chemistry is a genuine branch of science. I'm a chemist myself but I still can't help getting that image of that tiny little chemist taking a nap inside the s1 orbital of a hydrogen atom.
The hint you need can be found on this page at MacOS X Hints. Here's the relevant text:
So either set up the menu to use the command "open-x11 gimp" (no quotes), or change your
Sure we have. Of course we then CHECKED the web page in the browser we were coding to and found the mistake. Or at least we should have, if we were a corporation with the assets and resources of a company like Microsoft.
But then again, I guess Microsoft can't be bothered with checking for bugs before it releases anything, especially when if affects products other than theirs. They must have been more busy eliminating security holes in their own, bug-ridden servers.
Shouldn't that be Mac OS X.II.III?
If you want to really understand why it is called football, check out this encyclopedia.com article. Basically American Football and Soccer (another name for Worldwide Football) come from the same roots and are both entitled to the name football. This doesn't make either game any better or worse than the other and it is fine if Americans call their game football even if they can use their hands during play. Also, remember that in American Football you can use your feet at any time, using your hands is a personal choice.
Heh, I guess it is according to this definition. Hey, I don't make the definitions I just look them up.
Honestly if I had to define a ball in a sports context I would define it as a spherical or ellipsoidal object which is designed to be thrown, struck, carried, or otherwise propelled in accordance with the rules of the sport.
But that's just the way I see it, I'm sure that there are many people who would change it to just include spheres.
Yes, she will be in X-Men 2. Take a look at the IMDB information. She will probably also be in the commercial, as she was in the trailer.
First of all, from the American Heritage Dictionary (by way of Dictionary.com):
Ball
So a football is indeed, a ball.
Secondly you can use your feet at pretty much any time during play to move the football. Many times you can also use your hands or really any part of your body to move it. Given the choice between holding the ball and kicking it you will probably rather hold the ball rather than kick it but that doesn't stop you from doing either. In fact there are some times when you have to use your feet, such as kickoffs.
So the sport does have some right to be called football. It could more accurately be called "Foot and Hand Prolate Spheroid", but that's a lot more cumbersome and I don't think it will catch on.
The very act of requiring registration ends up cutting down the number of posts a web site receives. I know that I hardly ever post on a web site that requires registration, Slashdot is pretty much the exception for me. I wouldn't have even registered on Slashdot if it required me to put down easily identifiable personal information.
Even if the website in question did have people register, it would have needed a sure way to identify registrants, such as by credit card number. It said in the article that the troll's username was banned but the guy snuck back under other names. Unless they could find a sure way to identify the guy (such as Microsoft's Passport **shudder**), they couldn't stop the guy from posting.
It comes down to this: require people to totally identify themselves (thus causing them to ignore the site), or take the chance that you won't get trolled and leave the site open to all. Trolls are the ones that are driving stuff like Passport and national ID numbers, if people didn't abuse the privacy that certain forums provide then there wouldn't be a need to pin people down with big brother tactics.
Right, and it would help to use a fuel which has a low specific heat (that is, it takes little energy to heat it up) and also which doesn't take a lot of energy to go through phase changes. For each phase change a substance goes through it soaks up energy which could be better used in propulsion.
Hydrogen is better than water because hydrogen dissociates into a vapor with very little energy, where water takes a lot of energy to turn into steam. Water also will soak up a lot of energy in heating (high specific heat) up to the temperatures generated in the nuclear reaction, whereas hydrogen does not need as much energy to get up to temperature. In other words, you get more thrust out of equal masses of hydrogen and water with the same energy put into them.
However, there are other factors to consider. The main advantage of water is that it is easy to find, easy to store and pump around, can be used as a moderator for the nuclear reaction, can be used as shielding for the astronauts, the astronauts can use as their drinking supply, and they can use it to produce their oxygen supply. Hydrogen is a total mess to handle, its only real advantage is that it is a bit more energy efficient as a reaction mass. Water is generally accepted as a very good reaction mass due to these factors. The usability of water will most likely far outweigh any benefits you would get from using hydrogen.
That is why we have The Library of Congress. Here's a little blurb from their information page:
Exactly. If the options had been [Don't Save] [Save] then there would be very little confusion about what action is going to be taken.
One other cool idea in human interface design is to make the least destructive action the default action in any "dangerous" dialog box. For example:
Yeah, it's a little pain to not have the [Erase] button highlighted automatically, but it's worth the safeguard considering you are talking about the potential loss of all of your data.