I had an account with them when it was near unlimited downloads. I still have an account with them because they have good stuff and are still a lot cheaper.
You guys can bicker about the encoding rates, but they're pretty much as good as all of the other popular online music stores minus the DRM.
As for the price/subscription model. All you have to do is download 10 songs and you've broken even with the iTunes store. Hell, subscriptions can be good, it'll force you to listen to something new instead of that same Journey/Rush/Britney crap that everyone else has on their DAPs. Think about it, you're paying less, you can copy the tracks (remember how you could make mix tapes with music you bought?), and they carry A LOT of independent music.
I know I sound like I work for them, but it seems like they're not getting a fair shake. Try buying the almost every Pixies song recorded in one place for so cheap. I dare you.
They've got almost the whole 4AD catalog, most of what Mordam ever distributed (PUNK ROCK!) and a lot of jazz.
Maybe emusic isn't for everybody, but if you ever listen to new stuff on your own or buy more than one indie rock/punk rock/jazz record a month, then you'll be completely satisfied.
josephson junctions are incorporated into ring geometries as SQUIDs (superconducting quantum interference devices) which are finding many uses in medical imagery, sensitive magnetometry, ultrasensitive voltage metering, etc. in addition, arrays of these junctions are used in defining the volt since it is based on a physical effect and not an artifact.
oh yeah, brian josephson predicted the effect in '62 and it was observed in '65 so you're off by a decade.
also, since these devices are superconducting they don't generate heat the way conventional (normal state) wiring does. unless the junctions are driven into the normal state, they won't generate any resistive heating at all.
you know this mirkin business has been posted here two or three times already. let's just say it's not new anymore.
so let's ask, what are the direct applications? has anything been done so far which is electronically interesting? feel free to answer. i personally want to see a device made with this technology very soon.
while the latimes.com article is plugging the economical viability, let's get a handle on how much a scanning probe microscope costs (i think they're using a Park Scientific setup (now Thermomicroscopes)). i've seen they're machine and believe it's on the order of 100K. this is similar to what a used SEM and deposition equipment (metal evaporators, etc.) would cost. now look at the resolution. as far as i am aware, the minimum linewidth achieved has been on the order of 5 nm, while the consistent linewidths are something like 15- 30 nm. this is comparable to consistent linewidths in good SEM lithography.
while the technology is interesting, it's still a ways off from being useful and they are definitely making bank from the hype surrounding the technique. but we should still remember that other techniques have achieved comparable or far greater resolution such as STM electrodeposition and STM nanomanipulation (of ATOMS dammit!).
to the person that said quantum effects will limit the applications of molecular scale electronics, please be a bit more specific. all of solid-state electronics is quantum in origin, yet some of the 'quantum effects' you allude to may include weak-localization, universal conductance fluctuations, conductance quantization, etc. are these an issue at room temperature? depends on the mean free path and the electron-phonon scattering length. thermal fluctuations tend to smear out quantum interference effects at higher temperatures and coulomb blockade effects (ie, as in single electron transistors) also suffer from similar smearing.
okay, i'm figuring that i'm the only one posting that actually has experience in fabricating and measuring magnetic nanostructures so here goes:
the BBC article is typically crap. what happens is someone from cambridge or oxford needs PR so they call up the press and tell them how many transistors they can squeeze onto the head of a pin. in the end, there's really no science in the article and, for those astute readers out there, in this particular article they don't make much mention of how these things work, what material they are using, what temperature they've demonstrated these things at, etc.
Typically, these estimates on transistor density are made when the lab produces a prototype with the active elements within a certain area. by no means does this mean that they've constructed a 5.5 billion density device that works.
they don't tell you what the mechanism is-- tunneling magnetoresistance (TMR) or spin-diffusion/accumulation ('Johnson spin transistors'), however the switching speeds are estimated to be much faster than conventional semiconductor devices (there's some argument for this in IEEE spectrum from about 5 yrs back that i can't remember).
reliability? they have omitted mention of the gate mechanism here. how do they plan on switching these things individually? telepathy? if they are using EM fields generated by wires, then there is the inevitable heating to deal with. what material are they using? what's the curie temperature? how hot do they expect these things to get? hey wait! there's no size bar on that pretty picture of the magnets!?
blah blah blah. BAD JOURNALISM from the BBC.
i may be a jerk about this, but i think everyone's getting a bit caught up in the hype without enough data and it's irritating as a scientist.
palm=not really, uni-remote=not really, either
on
The Do-It-All Remote?
·
· Score: 1
the palm IR is pretty weak intensity-wise. i looked into doing this myself, but if you go to the URL where they sell the software to do this stuff, they also sell an amplifier that attaches to your palm to extend the range. otherwise the bare range of the pilot can be as short as a couple of feet and strongly contingent on your battery level.
anyhow, i think what the guy was asking about was being able to hit 'play cd'(or whatever) without having to manually configure the system state, ie, switching to the cd input, turning on the cd player, etc. on my tv, i've got three different video input channels and i've got to switch to a particular channel to watch dvd, or the vcr, etc. this initial setup, prior to the 'play' event is what needs to be automated and this is what the current crop of universal remotes doesn't do. they're just lookup tables for common buttons on remotes.
in theory, you could take the palm remote prog and program the whole sequence of button-down events that would correspond to a given final state. now if someone wants to figure out how to jack up the IR intensity of the palm, that would be supercool. i figure another hack would be to solder together a teeny transponder box that sits near you, within range, and just echoes your palm IR but at higher intensity.
of course, if you were an uber-geek, you would just program a microcontroller yourself to do all the sequential button events, and swap out the circuitry in a uni-remote with your own.
We should keep in mind what other forms of lithography are available and what constitutes a viable mass-produced fabrication method.
Currently, e-beam lithography can do 30 nm linewidths regularly, but no one is soiling their underwoos about it. Why? Because it's slow and your resolution drops when you try to expand the writing field (i.e., writing at a smaller magnifications). Then there are alignment issues, etc. All of these issues are applicable to 'dip pen lithography' as well and should be mentioned. Also, while this form of lithography is novel, and in it's own way neat, we still have to remember that IBM and a number of other research labs have been writing with single atoms (see http://www.almaden.ibm.com/vis/stm/stm.html).
I'm probably biased in all of this since the 'dip pen' guy is down the hall (literally) and my expertise is e-beam lithography and quantum transport, but when considering this sort of lithography in relation to computing, you have to think about useful electrical transport properties (although i know a lot of you may be touting mesoscopic nonlinear optics as the 'next wave') and it's all still very speculative and people are working very hard on these ideas.
Anyhow, all of this quantum computing talk bugs me, too, because it's really really really hard to implement real honest-to-goodness qubits. As far as I know they can now factor numbers on the order of 15. literally. And this difficulty in extending the range this does not scale linearly.
bad example. either way, hard disk encoding technology has to have a degree of redundancy built in so this sort of thing isn't so much of an issue. btw, typical dust particle diameters are in the range of 5-30 micrometers (ie 5-30 *10^-3 mm)... that's dust from the most common sources, skin cells, smokers, etc., which makes it an issue with current hard drives already.
either way, in that article they never make any statements about how they plan on spinning this theoretical drive, nor how they plan on aligning the disk perpendicular to the disk plane. errors of a few nm in tip to sample distance will crash your cantilever tip.
note also that they make no claims about transfer rates. have you ever actually seen how long it takes to scan a 5x5 micrometer^2 area with an AFM in non-contact mode?? you'll need better than 25 nm resolution (easy), but that area corresponds only to approximately 45000 bits (assuming that the a 'penny' has an area ~ 1 cm^2). are you willing to wait over a 1 s to read 5.5 K of data?? that's a little better than my c64's tape drive.
i haven't even gotten to the non-contact mode AFM measurement restrictions yet. basically, you're going to have some limitations in the reading rate if you're not oscillating your tip fast enough to resolve the bits spinning by. all of this is covered by Nyquist's sampling theory which determines the resolution you can attain for a sampling rate. i recall (i could be wrong) that most 1st and 2nd harmonic non-contact measurements are well under a MHz, and you have to cut that rate to cover your ass and get enough samples to say bit=on/off.
A few people are making devices to attempt to do faster, mass sequencing. Lydia Sohn's group at Princeton has assembled two-probe platinum devices which, at the present, only detect a change in capacitance when the DNA strand spans the gap b/w probes. Obviously this is pretty far from being able to sequence anything. The thing people forget about though is that human DNA is pretty huge (>~30 microns in length) and has been scanned succesfully by atomic force microscopy (AFM) in solution at room temperature (e.g. work by Lindsay's group at ASU >5 yrs ago). The big stumbling block in sequencing using electronic transport is an extremely sketchy knowledge of the electronic states one should expect as well as the inherent thermal (Johnson/Nyquist)noise at the temperature range that would not destroy the molecule.
Slashdot Mirror
You know, it's almost as if you all have never heard of the Cooper pair transistor:
http://www.google.com/search?q=cooper+pair+transistor
and i've got one.e riesbean.do?series=P7D
http://webshop.fujitsupc.com/fpc/Ecommerce/builds
I had an account with them when it was near unlimited downloads. I still have an account with them because they have good stuff and are still a lot cheaper.
You guys can bicker about the encoding rates, but they're pretty much as good as all of the other popular online music stores minus the DRM.
As for the price/subscription model. All you have to do is download 10 songs and you've broken even with the iTunes store. Hell, subscriptions can be good, it'll force you to listen to something new instead of that same Journey/Rush/Britney crap that everyone else has on their DAPs. Think about it, you're paying less, you can copy the tracks (remember how you could make mix tapes with music you bought?), and they carry A LOT of independent music.
I know I sound like I work for them, but it seems like they're not getting a fair shake. Try buying the almost every Pixies song recorded in one place for so cheap. I dare you.
They've got almost the whole 4AD catalog, most of what Mordam ever distributed (PUNK ROCK!) and a lot of jazz.
Maybe emusic isn't for everybody, but if you ever listen to new stuff on your own or buy more than one indie rock/punk rock/jazz record a month, then you'll be completely satisfied.
josephson junctions are incorporated into ring geometries as SQUIDs (superconducting quantum interference devices) which are finding many uses in medical imagery, sensitive magnetometry, ultrasensitive voltage metering, etc. in addition, arrays of these junctions are used in defining the volt since it is based on a physical effect and not an artifact.
oh yeah, brian josephson predicted the effect in '62 and it was observed in '65 so you're off by a decade.
also, since these devices are superconducting they don't generate heat the way conventional (normal state) wiring does. unless the junctions are driven into the normal state, they won't generate any resistive heating at all.
you know this mirkin business has been posted here two or three times already. let's just say it's not new anymore.
so let's ask, what are the direct applications? has anything been done so far which is electronically interesting? feel free to answer. i personally want to see a device made with this technology very soon.
while the latimes.com article is plugging the economical viability, let's get a handle on how much a scanning probe microscope costs (i think they're using a Park Scientific setup (now Thermomicroscopes)). i've seen they're machine and believe it's on the order of 100K. this is similar to what a used SEM and deposition equipment (metal evaporators, etc.) would cost. now look at the resolution. as far as i am aware, the minimum linewidth achieved has been on the order of 5 nm, while the consistent linewidths are something like 15- 30 nm. this is comparable to consistent linewidths in good SEM lithography.
while the technology is interesting, it's still a ways off from being useful and they are definitely making bank from the hype surrounding the technique. but we should still remember that other techniques have achieved comparable or far greater resolution such as STM electrodeposition and STM nanomanipulation (of ATOMS dammit!).
to the person that said quantum effects will limit the applications of molecular scale electronics, please be a bit more specific. all of solid-state electronics is quantum in origin, yet some of the 'quantum effects' you allude to may include weak-localization, universal conductance fluctuations, conductance quantization, etc. are these an issue at room temperature? depends on the mean free path and the electron-phonon scattering length. thermal fluctuations tend to smear out quantum interference effects at higher temperatures and coulomb blockade effects (ie, as in single electron transistors) also suffer from similar smearing.
they're already doing this at IBM Almaden.
conveniently it's call MRAM.
okay, i'm figuring that i'm the only one posting that actually has experience in fabricating and measuring magnetic nanostructures so here goes:
the BBC article is typically crap. what happens is someone from cambridge or oxford needs PR so they call up the press and tell them how many transistors they can squeeze onto the head of a pin. in the end, there's really no science in the article and, for those astute readers out there, in this particular article they don't make much mention of how these things work, what material they are using, what temperature they've demonstrated these things at, etc.
Typically, these estimates on transistor density are made when the lab produces a prototype with the active elements within a certain area. by no means does this mean that they've constructed a 5.5 billion density device that works.
they don't tell you what the mechanism is-- tunneling magnetoresistance (TMR) or spin-diffusion/accumulation ('Johnson spin transistors'), however the switching speeds are estimated to be much faster than conventional semiconductor devices (there's some argument for this in IEEE spectrum from about 5 yrs back that i can't remember).
reliability?
they have omitted mention of the gate mechanism here. how do they plan on switching these things individually? telepathy? if they are using EM fields generated by wires, then there is the inevitable heating to deal with. what material are they using? what's the curie temperature? how hot do they expect these things to get? hey wait! there's no size bar on that pretty picture of the magnets!?
blah blah blah.
BAD JOURNALISM from the BBC.
i may be a jerk about this, but i think everyone's getting a bit caught up in the hype without enough data and it's irritating as a scientist.
the palm IR is pretty weak intensity-wise. i looked into doing this myself, but if you go to the URL where they sell the software to do this stuff, they also sell an amplifier that attaches to your palm to extend the range. otherwise the bare range of the pilot can be as short as a couple of feet and strongly contingent on your battery level.
anyhow, i think what the guy was asking about was being able to hit 'play cd'(or whatever) without having to manually configure the system state, ie, switching to the cd input, turning on the cd player, etc. on my tv, i've got three different video input channels and i've got to switch to a particular channel to watch dvd, or the vcr, etc. this initial setup, prior to the 'play' event is what needs to be automated and this is what the current crop of universal remotes doesn't do. they're just lookup tables for common buttons on remotes.
in theory, you could take the palm remote prog and program the whole sequence of button-down events that would correspond to a given final state.
now if someone wants to figure out how to jack up the IR intensity of the palm, that would be supercool. i figure another hack would be to solder together a teeny transponder box that sits near you, within range, and just echoes your palm IR but at higher intensity.
of course, if you were an uber-geek, you would just program a microcontroller yourself to do all the sequential button events, and swap out the circuitry in a uni-remote with your own.
We should keep in mind what other forms of lithography are available and what constitutes a viable mass-produced fabrication method.
Currently, e-beam lithography can do 30 nm linewidths regularly, but no one is soiling their underwoos about it. Why? Because it's slow and your resolution drops when you try to expand the writing field (i.e., writing at a smaller magnifications). Then there are alignment issues, etc. All of these issues are applicable to 'dip pen lithography' as well and should be mentioned. Also, while this form of lithography is novel, and in it's own way neat, we still have to remember that IBM and a number of other research labs have been writing with single atoms (see http://www.almaden.ibm.com/vis/stm/stm.html).
I'm probably biased in all of this since the 'dip pen' guy is down the hall (literally) and my expertise is e-beam lithography and quantum transport, but when considering this sort of lithography in relation to computing, you have to think about useful electrical transport properties (although i know a lot of you may be touting mesoscopic nonlinear optics as the 'next wave') and it's all still very speculative and people are working very hard on these ideas.
Anyhow, all of this quantum computing talk bugs me, too, because it's really really really hard to implement real honest-to-goodness qubits. As far as I know they can now factor numbers on the order of 15. literally. And this difficulty in extending the range this does not scale linearly.
my 2x10^-2 [$].
grains of sand that are 100 nm??
bad example. either way, hard disk encoding technology has to have a degree of redundancy built in so this sort of thing isn't so much of an issue. btw, typical dust particle diameters are in the range of 5-30 micrometers (ie 5-30 *10^-3 mm)... that's dust from the most common sources, skin cells, smokers, etc., which makes it an issue with current hard drives already.
either way, in that article they never make any statements about how they plan on spinning this theoretical drive, nor how they plan on aligning the disk perpendicular to the disk plane. errors of a few nm in tip to sample distance will crash your cantilever tip.
note also that they make no claims about transfer rates. have you ever actually seen how long it takes to scan a 5x5 micrometer^2 area with an AFM in non-contact mode?? you'll need better than 25 nm resolution (easy), but that area corresponds only to approximately 45000 bits (assuming that the a 'penny' has an area ~ 1 cm^2). are you willing to wait over a 1 s to read 5.5 K of data?? that's a little better than my c64's tape drive.
i haven't even gotten to the non-contact mode AFM measurement restrictions yet. basically, you're going to have some limitations in the reading rate if you're not oscillating your tip fast enough to resolve the bits spinning by. all of this is covered by Nyquist's sampling theory which determines the resolution you can attain for a sampling rate. i recall (i could be wrong) that most 1st and 2nd harmonic non-contact measurements are well under a MHz, and you have to cut that rate to cover your ass and get enough samples to say bit=on/off.
ah heck. i need to get out more.
A few people are making devices to attempt to do faster, mass sequencing. Lydia Sohn's group at Princeton has assembled two-probe platinum devices which, at the present, only detect a change in capacitance when the DNA strand spans the gap b/w probes. Obviously this is pretty far from being able to sequence anything. The thing people forget about though is that human DNA is pretty huge (>~30 microns in length) and has been scanned succesfully by atomic force microscopy (AFM) in solution at room temperature (e.g. work by Lindsay's group at ASU >5 yrs ago). The big stumbling block in sequencing using electronic transport is an extremely sketchy knowledge of the electronic states one should expect as well as the inherent thermal (Johnson/Nyquist)noise at the temperature range that would not destroy the molecule.