No, you're confused. All light in a vacuum travels at the same speed. But in many mediums blue light propagates faster than red. That's WHY colors are refracted differently in a prism; the angle of refraction depends on the ratio of the speed of light inside the prism and out (Snell's law).
And for God's sake stop crapping ellipses everywhere, OK?
Re:Did any one else notice...
on
Mac Case Mods
·
· Score: 3, Informative
Not to mention the actual data, which is moving around in circles 5400 cycles/minute with respect to the "stationary" magnet.
Sure, but what Apple should have done was present aliases to the UNIX layer as though they were regular files (or maybe hard links,) rather than making them completely opaque to standard UNIX tools.
This theme is prevalent throughout OS X: Whenever Mac OS has historically done something one way and UNIX another, Mac OS *doesn't* pick a side, and you end up with massive incompatibilities between different parts of the *same* operating system. I occasionally boot into OS X for a few days, but invariably I get bitten by things like the schizoid treatment of aliases, or the fact that cp(1) doesn't actually copy files since it leaves off the resource fork, and I retreat back to running Debian on the iBook.
Alias semantics are kind of fux0red anyway. They contain both a (non-relative) pathname and an HFS file identifier, so that they they act just like hard links, except that when thet fails then they act just like symbolic links--without updating the "hard link" pointer! And when they act like hard links they fail to update the symbolic link pointer. And then at other times they just act screwy. I have bad pre-OS X memories of *every* alias getting broken at once when you did things like change the name of the hard disk drive, or restore a drive from backups. The problem is their behavior is complex enough that you can't predict what actions are going to break them without knwoledge of all the previous things that went on on the filesystem.
Ah, yes, that's the book where Hofsteader devotes 20% of the content to an exposition of Goedel's incompleteness theorem that, even for a layperson's book, manages to be simultaneously belabored and simplistic. 10% of the content muses about Bach's music in an even more simplistic manner. Occasionally, he mentions Escher or includes a picture just for the hell of it. The rest of the book is devoted to sheer intellectural wankery, devoted to just how goddamned clever Hofsteader considered himself to be:
"I know, I'll write a piece about a recording that fails to resolve, and my essay will also fail to resolve!"
"I know, I'll write a vignette that mentions acrostics, and it will itself be an acrostic!"
"I know, I'll write an essay about a mirror fugue, and the essay will itself read the same forwards and backwards!"
"I know, I'll write an chapter about recursion, and that chapter will itself be recursive!"
Gah. That little trick got old after its first use.
He has a point in that the old style of door lever is annoyingly easy to catch your sleeve, or the strap of your bag, or your hip (ouch!) on. But he could have made a better point by noting that the modern style of door lever curves back towards the door at the end, solving all of those problems while remaining equally accessible.
Sure, make it a language requirement, that'll fix everything. Nowadays I usually see XHTML-compliant web sites with alt="" everywhere, or even alt="Enter alternate text here".
I stopped using gnuPod since it didn't support ordering (i.e., if I added all the songs in an album, they'd show up on the iPod in alphabetical order, rather than the proper order determined by the track numers in the id3 tag. gnuPOD also doesn't do synchronization, and the hoops you have to go through to remove files from the iPod are rather cumbersome.
SyncPOD seems to work better for me. It has its own limitations and bugaboos, but it knows how to do correct ordering. I threw together a script which select albums from my collection at random to fill 5GB of space and makes symlinks to the selected mp3 files inside SyncPOD's synchronization directory. It works, after a little debugging (be warned that SyncPOD in its present release doesn't escape spaces or any other characters in filenames which might be interpreted by the shell.)
Alternatively, you could simply wear a head tracker and render it in real time.
Volumetric displays are low-res, uber-expensive and cannot depict absorptivity or occlusion (everything projected by a volumetric display is transparent.) They are nice for some applications where 360-degree walk-around ability is useful (I can see how one would use them for air traffic control) but not for, say, playing Quake. The two technologies definitely occupy different niches.
Re:Does anybody have more info?
on
3D LCD Display
·
· Score: 1
The parallax blocker is not switchable; in 2d mode the same image is sent to both fields.
The winners include a robotics researcher from Dartmouth studying robotics, and a paleoethnobotanist from Penn State studying the ancient plants and foods of prehistoric peoples.
Among the other nominees I see we have a seismologist studying earthquakes, a historian studying history, and a novelist writing books.
Look, all I know is when I play a DJ mix that weighs in at ~100 MB, there are three repeatable points where it pauses and spins up the HD. What version of the iPod/firmware do you have?
I currently own a 5GB iPod and have a few complaints.
Overall, the machine is quite good and probably the best on the market. However ther are a few things that it doesn't get right.
First, gap removal -- I have many albums that arte contimuous (live recordings, DJ mixes, classical music, etc.) The iPod provides no gap suppression, so that in between every track there is a noticeable gap of about 1/2 second (or up to five seconds if the hard disk decides to spin up at the same time.) Now, I realize that due to the architecture of most portable mp3 players, gap suppression is not feasible because it requires processing on the decoded audio. So I went and re-encoded all those albums as single mp3s. However, that didn't work well because of:
File size limit: The iPod is very poor at handling files that exceed the size of its 32MB memory buffer. It is incapable of playing music while reading from the hard disk. So if you have a file that is longer than 32mb, it will play the first 32mb, then pause for 3-5 seconds while reading the next 32mb chunk into memory. This means that there is no way to properly listen to continuously recorded albums.
Furthermore, the iPod provides no mechanism for bookmarking or labeling points within a track, so it's impossible for me to see what the title of the current section on my continuously encoded album is. I would find this even more annoying if I listened to audio books.
The backlight is not adjustable, and it's too bright. In a dark room it hurts my eyes.
The backlight, unlike most other kinds of backlight, needs to invert the screen when it's on, which you can see if you take the iPod out into the sunlight. But on a cloudy day, the backlight and the ambient light balance out almost exactly, and the display is unreadable. I can hold down the "Menu" key to turn the backlight off, but that isn't helpful because when I move the wheel the backlight turns on agin immediately. So I have to navigate through the menu system (which is tricky when you can't see the display) to turn off the backlight.
Did I mention the menu interface? The menu interface provides no provision for muscle memory; it cannot be operated by touch. You must be constantly looking at the display while you move the wheel. This makes the iPod downright dangerous for use in the car (which is about 50/70% of where I use the thing). Much of the danger could be alleviated if the wheel provided any sort of tactile feedback -- there is a audible "clicker" you can enable, but you cannot hear it in a noisy environment, or while the music is playing. You cannot adjust the volume unless you are in the "Now Playing" section of the menu interface. If you wanted to turn down the volume without looking at the display, the sequence you have to go through is this:
Press Menu a bunch to get you out to the top level
turn the wheel clockwise to get to "Now Playing"
Press the center button (watch out, the center button is part of the wheel too, so that when you move your thumb you might accidentally move the wheel and pick the wrong menu item)
Finally turn the wheel counter-clockwise to reduce the volume.
That's a little much to expect when you're trying to just mute the damn thing while keeping your eyes on the road!
Finally, iTunes seems to have some speed issues in reading files off of CD-ROMs. Off the hard drive is nice and speedy, but from the CD it clocks in at around USB1.0 speeds. I don't know why this is the case.
I would like to know if there are any portable hard-drive based mp3 players which address these issues.
First stop: Many colleges are publishing homework and lecture notes online nowadays. Leech off of those. You will still need some textbooks though.
I'm going to assume you want to learn some physics, as opposed to learning about physics. If this is the case, you can ignore stuff like "Black Holes and Time Warps" and "A Brief History of Time" -- they're good bathroom reading material but won't actually get you anywhere in your understanding.
Next I'm going to assume you have had enough calculus to be able to differentiate any function and integrate some of them. If not, well, you need to learn some calculus first off (You might be able to do this concurrent with reading Serway; it could help solidify the concepts.)
For introductory fare, try Serway's Physics for Scientists and Engineers. Don't let the title put you off--there's an unspoken law of textbook publishing where you have to inflate the titles of easy books and deflate the title of hard books. A book subtitled "For Scientists and Engineers" will usually be easier than one with "Elementary" or "Basic" prepended to its title. Serway has good exercises (for any book you use, do the problems or you won't learn anything! You don't have to do all of them, but enough so that you can look at the ones you haven't done and see what a good approach should be.)
Serway will cover mechanics pretty well. Passing out of Newtonian mechanics and getting into real physics now, there are several areas of physics which the typical undergraduate science education touches on. These are, approximately, Electricity and Magnetism, Special Relativity, Wave Mechanics, Quantum Mechanics, and Statistical Mechanics/Thermodynamics. In order:
E&M -- Purcell's book "Electricity & Magnetism" is easily the bast text I had out of my entire college career (and this comes from a non-physics major). It is heavy on visual thinking and introduces you to new mathamatical tools (e.g. vector calculus) when you need them. It also has bits on special relativity (the unification of SR and E&M is the most beautiful piece of physics that most people will ever be able to understand.)
Special Relativity -- I like Einstein's "Relativity: The Special and General Theories." No exercises though--when I was in school, we used Wheeler's "Spacetime Physics" which is just plain incoherent.
Wave Mechanics -- This is what you need to know to be able to parse the occasional/. stories about physicists stopping light and/or making materials with negative refractivity. Crawford's "Waves" is probably my second favorite text of all time. Unfortunately, I hear it's out of print. Try to find a used copy. It (along with Purcell's E&M) is part of the "Berkeley physics course" series, and shares some strong points with Purcell--timely introduction to mathmatical techniques (you need a bit of differential equations and Fourier transforms this time) and a relatively relaxed exposition.
Quantum Mechanics and Statistical Mechanics/Thermodynamics -- Unfortunately I can't really recommend the books I've used for these subjects. You may want to look at the other volumes in the Berkeley series, since I've had good luck with Purcell and Crawford's books. Christoph Adami's "Introduction to Artificial Life" solidified the concepts of entropy and heat for me much better than any of the pure stat. mech. texts I had, so I recommend it as a supplement (and a fascinating subject in itself.)
Anyway, that should keep you busy for a while;)
Re:The optimal state of any linear game is a draw
on
Awari Solved
·
· Score: 1
If you claim that the RISC PPC is a cleaner nicer
architecture because its RISC, then in fact to emulate it will be even easier to do than the 68K (a CISC) emulation.
What you're failing to consider is that the PPC has way more registers than the x86 chip. Specifically, 32 general-purpose integer registers, 32 FP registers, 32 AltiVec registers, 16 segment registers, and five miscellaneous others.
Compare with the P4-- 8 integer registers, 8 FP registers, 8 MMX registers, 8 SSE2 registers, and miscellaneous others.
This means that a PPC emulating x86 instructions has registers to spare for decoding operations, while the P4 trying to emulate the PC will necessarily waste a lot of time sawpping register values between chip and cache. Dynamic recompilation can address some of this, but it is not magic.
"Stills camera" refers to a camera that takes still pictures, which are the cameras on the ground being used by onlookers -- not the camera being used by the the movie crew. That would be a "motion picture camera."
The Gnut client will drop any connections that it sees too many duplicate packets on. However, it doesn't help with the badwidth problem that I can see, since the bandwidth consumption is due to the rebroadcasting nature of the network and not necessarily the fact that you're recieving duplicate packets.
Slashdot Mirror
I'm sure you could just scrape all of the fallen pieces into a big bin and pour them into an optical counting machine.
Dear Hazzzard:
No.
Sincerely,
Record Company CEOs.
at the same speed. But in many mediums blue light propagates faster than red. That's WHY colors are refracted differently in a prism; the angle of refraction depends on the ratio
of the speed of light inside the prism and out (Snell's law).
And for God's sake stop crapping ellipses everywhere, OK?
Not to mention the actual data, which is moving around in circles 5400 cycles/minute with respect to the "stationary" magnet.
Try this:
1) Rename your hard disk
2) Replace a file that was pointed to by your alias.
Congratulations, you've now broken your alias. Enjoy.
Sure, but what Apple should have done was present aliases to the UNIX layer as though they were regular files (or maybe hard links,) rather than making them completely opaque to standard UNIX tools.
This theme is prevalent throughout OS X: Whenever Mac OS has historically done something one way and UNIX another, Mac OS *doesn't* pick a side, and you end up with massive incompatibilities between different parts of the *same* operating system. I occasionally boot into OS X for a few days, but invariably I get bitten by things like the schizoid treatment of aliases, or the fact that cp(1) doesn't actually copy files since it leaves off the resource fork, and I retreat back to running Debian on the iBook.
Alias semantics are kind of fux0red anyway. They contain both a (non-relative) pathname and an HFS file identifier, so that they they act just like hard links, except that when thet fails then they act just like symbolic links--without updating the "hard link" pointer! And when they act like hard links they fail to update the symbolic link pointer. And then at other times they just act screwy. I have bad pre-OS X memories of *every* alias getting broken at once when you did things like change the name of the hard disk drive, or restore a drive from backups. The problem is their behavior is complex enough that you can't predict what actions are going to break them without knwoledge of all the previous things that
went on on the filesystem.
"I know, I'll write a piece about a recording that fails to resolve, and my essay will also fail to resolve!"
"I know, I'll write a vignette that mentions acrostics, and it will itself be an acrostic!"
"I know, I'll write an essay about a mirror fugue, and the essay will itself read the same forwards and backwards!"
"I know, I'll write an chapter about recursion, and that chapter will itself be recursive!"
Gah. That little trick got old after its first use.
He has a point in that the old style of door lever is annoyingly easy to catch your sleeve, or the strap of your bag, or your hip (ouch!) on. But he could have made a better point by noting that the modern style of door lever curves back towards the door at the end, solving all of those problems while remaining equally accessible.
Sure, make it a language requirement, that'll fix everything. Nowadays I usually see XHTML-compliant web sites with alt="" everywhere, or even alt="Enter alternate text here".
I stopped using gnuPod since it didn't support ordering (i.e., if I added all the songs in an album, they'd show up on the iPod in alphabetical order, rather than the proper order determined by the track numers in the id3 tag. gnuPOD also doesn't do synchronization, and the hoops you have to go through to remove files from the iPod are rather cumbersome.
SyncPOD seems to work better for me. It has its own limitations and bugaboos, but it knows how to do correct ordering. I threw together a script which select albums from my collection at random to fill 5GB of space and makes symlinks to the selected mp3 files inside SyncPOD's synchronization directory. It works, after a little debugging (be warned that SyncPOD in its present release doesn't escape spaces or any other characters in filenames which might be interpreted by the shell.)
Volumetric displays are low-res, uber-expensive and cannot depict absorptivity or occlusion (everything projected by a volumetric display is transparent.) They are nice for some applications where 360-degree walk-around ability is useful (I can see how one would use them for air traffic control) but not for, say, playing Quake. The two technologies definitely occupy different niches.
The parallax blocker is not switchable; in 2d mode the same image is sent to both fields.
Among the other nominees I see we have a seismologist studying earthquakes, a historian studying history, and a novelist writing books.
If Terminal is closed or has no open windows, clicking on it starts a new terminal.
If Terminal has windows open, clicking on it brings those windows forward.
If Terminal has windows open but they are minimized, clicking on it has no apparent effect other than changing your menubar.
"Document-based," Ha. That's a good one.
Look, all I know is when I play a DJ mix that weighs in at ~100 MB, there are three repeatable points where it pauses and spins up the HD. What version of the iPod/firmware do you have?
Overall, the machine is quite good and probably the best on the market. However ther are a few things that it doesn't get right.
First, gap removal -- I have many albums that arte contimuous (live recordings, DJ mixes, classical music, etc.) The iPod provides no gap suppression, so that in between every track there is a noticeable gap of about 1/2 second (or up to five seconds if the hard disk decides to spin up at the same time.) Now, I realize that due to the architecture of most portable mp3 players, gap suppression is not feasible because it requires processing on the decoded audio. So I went and re-encoded all those albums as single mp3s. However, that didn't work well because of:
File size limit: The iPod is very poor at handling files that exceed the size of its 32MB memory buffer. It is incapable of playing music while reading from the hard disk. So if you have a file that is longer than 32mb, it will play the first 32mb, then pause for 3-5 seconds while reading the next 32mb chunk into memory. This means that there is no way to properly listen to continuously recorded albums.
Furthermore, the iPod provides no mechanism for bookmarking or labeling points within a track, so it's impossible for me to see what the title of the current section on my continuously encoded album is. I would find this even more annoying if I listened to audio books.
The backlight is not adjustable, and it's too bright. In a dark room it hurts my eyes.
The backlight, unlike most other kinds of backlight, needs to invert the screen when it's on, which you can see if you take the iPod out into the sunlight. But on a cloudy day, the backlight and the ambient light balance out almost exactly, and the display is unreadable. I can hold down the "Menu" key to turn the backlight off, but that isn't helpful because when I move the wheel the backlight turns on agin immediately. So I have to navigate through the menu system (which is tricky when you can't see the display) to turn off the backlight.
Did I mention the menu interface? The menu interface provides no provision for muscle memory; it cannot be operated by touch. You must be constantly looking at the display while you move the wheel. This makes the iPod downright dangerous for use in the car (which is about 50/70% of where I use the thing). Much of the danger could be alleviated if the wheel provided any sort of tactile feedback -- there is a audible "clicker" you can enable, but you cannot hear it in a noisy environment, or while the music is playing. You cannot adjust the volume unless you are in the "Now Playing" section of the menu interface. If you wanted to turn down the volume without looking at the display, the sequence you have to go through is this:
That's a little much to expect when you're trying to just mute the damn thing while keeping your eyes on the road!
Finally, iTunes seems to have some speed issues in reading files off of CD-ROMs. Off the hard drive is nice and speedy, but from the CD it clocks in at around USB1.0 speeds. I don't know why this is the case.
I would like to know if there are any portable hard-drive based mp3 players which address these issues.
I'm going to assume you want to learn some physics, as opposed to learning about physics. If this is the case, you can ignore stuff like "Black Holes and Time Warps" and "A Brief History of Time" -- they're good bathroom reading material but won't actually get you anywhere in your understanding.
Next I'm going to assume you have had enough calculus to be able to differentiate any function and integrate some of them. If not, well, you need to learn some calculus first off (You might be able to do this concurrent with reading Serway; it could help solidify the concepts.)
For introductory fare, try Serway's Physics for Scientists and Engineers. Don't let the title put you off--there's an unspoken law of textbook publishing where you have to inflate the titles of easy books and deflate the title of hard books. A book subtitled "For Scientists and Engineers" will usually be easier than one with "Elementary" or "Basic" prepended to its title. Serway has good exercises (for any book you use, do the problems or you won't learn anything! You don't have to do all of them, but enough so that you can look at the ones you haven't done and see what a good approach should be.)
Serway will cover mechanics pretty well. Passing out of Newtonian mechanics and getting into real physics now, there are several areas of physics which the typical undergraduate science education touches on. These are, approximately, Electricity and Magnetism, Special Relativity, Wave Mechanics, Quantum Mechanics, and Statistical Mechanics/Thermodynamics. In order:
Anyway, that should keep you busy for a while
So are you saying you can beat me at tic-tac-toe?
architecture because its RISC, then in fact to emulate it will be even easier to do than the 68K (a CISC) emulation.
What you're failing to consider is that the PPC has way more registers than the x86 chip. Specifically, 32 general-purpose integer registers, 32 FP registers, 32 AltiVec registers, 16 segment registers, and five miscellaneous others.
Compare with the P4-- 8 integer registers, 8 FP registers, 8 MMX registers, 8 SSE2 registers, and miscellaneous others.
This means that a PPC emulating x86 instructions has registers to spare for decoding operations, while the P4 trying to emulate the PC will necessarily waste a lot of time sawpping register values between chip and cache. Dynamic recompilation can address some of this, but it is not magic.
dude, don't flame people who take your side in an argument.
Better watch out, or Apple will shut you down with the DMCA since Quartz Extreme was intended only for approved video cards.
Sorry to burst your bubble, but the figure was 10.1% of teens who actively download music.
Generally, all RAMs are asynchronous, except for SDRAM.
"Stills camera" refers to a camera that takes still pictures, which are the cameras on the ground being used by onlookers -- not the camera being used by the the movie crew. That would be a "motion picture camera."
The Gnut client will drop any connections that it sees too many duplicate packets on. However, it doesn't help with the badwidth problem that I can see, since the bandwidth consumption is due to the rebroadcasting nature of the network and not necessarily the fact that you're recieving duplicate packets.