This reminds me of an episode of one of the cartoons I read. Written by a Nuclear Engineering PhD at Berkeley, the strip is quite funny. Here is the one this reminds me of.
(For those of you who don't know, a waveguide is basically a wire or metal box connecting two or more locations allowing EM waves to travel. One common example of a waveguide would be coax cable.)
Re:18, it's a magic number.
on
Making Change
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· Score: 2, Informative
Regarding the ancient, mystic aspect of your post, I think I can explain the history behind this some. In the old hebrew counting system, the leters were used for numbers (but it was decimal, it's just that they used letters instead of the current notation), and the letters for 18 spelled out the word for life. Hence, 18 was (and still is by some people) considered lucky.
Cohen-Tannoudji is by far the best quantum book if you want the full mathematical rigor. Feynman has several good books, both his introductory level explanatory stuff in his lectures on physics and an introduction to the path integral formulation of physics. However, based on your question, I am going to have to go with Cohen-Tannoudji.
Yes, you do in fact get an induced current. However, as demonstrated vividly by a question on my final when I was taking first semester E&M, you need somewhere on the order of 200,000 loops of wire to get enough induced current to be worthwhile from 20,000V power lines. (The exact question was, is it feasible to steal power by placing a coil between two 20,000V power transmission lines.) I'm pretty sure you don't care about the negligible effects (unless you're paranoid, or your bike is composed of 200,000 loops of wire).
Go with a flexible language as a first language. You don't want them stuck using only one programming paradigm. If possible, choose something that can do OOP, functional, logic, etc. It will serve them well down the road if they ever want to use it for anything not to be stuck in just one paradigm.
I have two different suggestions, depending on the type of keyboard you prefer.
If you prefer the laptop style keyboard (as in thin keys and very little noise from the keyboard), go with the TypeMatrix keyboard. It's a dvorak style key layout, although the keys are reprogrammable, with laptop style keys and all sorts of special keys. Additionally, the keys go straight up and down, rather than at angles. A picture is available here. My roommate uses one and loves it.
Alternatively, if you are a big fan of the "kacink" (tactile feedback) style keyboard, go with the old IBM keyboard. If you don't want it making so much noise, put a piece of foam under the keyboard. Aparently, the reason they are so noisy is the table underneath acts as a resonating board, so the foam dampens this effect.
As some have already noted, the actual wording is that the vouchers are good for ANY computer product. I propose that people use these vouchers to fund your favorite linux distribution or open source group. Let's use Microsoft's money to fund their competetion.
Human Growth Hormone is usually used to treat hormone deficiencies in children. My brother needs to take it by injection daily because he has a thyroid binding deficiency, but he's only 5 years old, and will probably stop taking it before he is 18. While it has been well studied on children, it's effects on adults are nowhere near as well studied. While some people believe it is something of a "fountain of youth," this has yet to be found to be true under any studies, and no long term safety tests have been run on adults. So, the conclusion is that you were right to be mighty suspicious of that spam you keep getting.
Re:They're still available
on
Low Tech Toys?
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· Score: 3, Informative
Just some information. There's a chain store called The Nature Store (can be found in many malls) which also has an online presencs that carries kaleidoscopes. I was looking for them when I posted, and didn't initially find them, but they have a website at http://thenaturestore.com.
Of course, they won't show up if you do a search on their site, but they do in fact cary them, because I stumbled across one through google. The one I found was at http://thenaturestore.com/kidkidtoys.htm. Hope this helps.
They're still available
on
Low Tech Toys?
·
· Score: 2, Informative
You just have to know where to look. Most of the stores that cary more educational toys cary at least one model of kaleidoscope. You can even find places that will sell fancy kaleidoscopes with interchangable glass tubes filled with oil and whatever the other stuff is that falls by the window to create the paterns. I'm not sure if you can still find the inexpensive ones that don't use glass, but kaleidoscopes are definetely an excellent toy. Good luck in your search.
Just thought I should point out that this isn't a Jury trial. In Norway, one doesn't have the right to a jury trial. Nonetheless, your point is valid, and even more relevent, since a judge is much more likely to notice this than an untrained jury.
I know, most of the first level tech support people are morons. However, sometimes, if you confuse them enough and give evasive enough answers, they'll let you through to a higher level person if you ask. Some of the higher level people actually know stuff. My roommate managed to get all the way through to one of their sysadmins (we have problems establishing reliable UDP connections to some ISP's, but only if it goes through one link, and they were able to confirm where the problem was). So, the answer is, confuse the hell out of the first level people by talking about networking protocols and you might actually get through to a real sysadmin.
Actually, the heat tube works quite well. Heat tubes are used in many high end servers were cooling is critical. In fact, heat tubes can be better than the traditional heat sink/fan combo. There is a review of the athlon version of this system at http://www.tech-report.com/reviews/2002q3/shuttle- ss40g/index.x?pg=1 complete with benchmarks and comparison tests. So, if it's good enough to keep your athlon cool, it's good enough for just about anything.
Re:this one I never forget..
on
Science Askew
·
· Score: 1
This fails both under quantum physics and general relativity.
Under the quantum physics interpretation, since both the cat's feet and the buttered toast are equally likely to land on the floor, the cat-toast enters a superposition where both cat and toast are simultaneously on the floor until it is observed, at which point a radioactive particle decays, and the cat is skinned in a number of simultaneous, equally likely, yet distinct ways.
Relativity predicts that the intense attraction to the floor will, in fact, bend space-time in such a way that the floor actually is in contact with both the cat and the toast. If the cat is of the black variety, then it will thus cross its own path, generate a singularity, and vanish in a puff of logic.
The debate continues, as attempts at experimental verification have thus far failed. Dr. Kibble at Princeton's IAS said, "Look, have YOU ever tried to hold a cat still and strap some friggin' TOAST to its back?"
I can't say I came up with this (it came from a post to an article several months ago), but I have to admit, it's a great response to the classic cat/buttered toast joke.
I don't think you know how SETI@home works. First of all, it's pretty clear you don't even know how the program works. Every work unit is sent out to at least 3 computers so that results can be verified. However, since we send out so many workunits (as in, we can clog a 100 Mbit pipe, and these workunits aren't exactly huge), the system may send a workunit out more than the minumum amount of times. So a workunit may be sent out more times than necessary, but won't be sent out less times than necessary. If we aren't splitting tapes fast enough to keep up with demand, workunits will be sent to more people. We do this, because otherwise we wouldn't be able to satisfy the demands of the users, and redundancy is good. It's simply not worth our time to be going after every suspected case of cheating (as in, we have better things to do, especially since there's only a few of us).
Now, on to all of the flamebait about open source. The infrastructure for the next generation of SETI@home, BOINC is open source. In fact, we would like your help on it looking for bugs and security holes. So if you want to help, visit http://boinc.ssl.berkeley.edu and help find bugs in our code. Thanks,
Mike Gary
Berkeley SETI project
In the mathematical sense, the dimensionality of an object refers to how many dimensions the object itself has, not the dimensionality of the ambient space. A 2-sphere, denoted S2, lives in R3. However, if you examine the surface itself, it is a 2 dimensional surface (as in, a basis for the points on the 2 sphere has only 2 elements). When doing math, dimensionality is a property of the object, not of the ambient space. When you think about this, it makes sense, since there are plenty of examples of 2 dimensional objects which cannot be found in less than 4 examples, the most common of which is the klein-bottle (think of a torus, except it intersects itself if represented in 3 dimensions, since it's made out of a mobius strip instead of an anulus).
Sometimes, scientists will also use the word "model" as something in-between, but most often it is used by engineers using well-known theories to model complex phenomena.
This reminds me of something my physics professor said in lecture on Tuesday while discussing why the Bohr model of the atom was not only bad, but unphysical. Paraphrasing him, a model is something which somewhat describes some of the data. In other words, we know it's completely wrong, but it works some of the time and is useful for understanding the actual situation.
and a physics student at UC Berkeley, I thought I would just provide a little more information for those of you who are too lazy to read the article. SETI@home has been collecting data at the Arecibo radio telescope for the last several years, and we have observed pretty much everything that is visible from that location. We are building a new data recorder that will be capable of observing broadband data/many independent narrow bands, and we will be using this to observe in Australia. We have also applied to re-observe any interesting locations we have found at Arecibo, using this new equipment.
For the last several years, we have been using the data we have gathered for several purposes, amongst which are mapping the Hydrogen distrobution in the milky way and searching for SETI. We are about to start a new project that will search for broadband pulses (which must be very short in durration), which can be encoded to have a reverse dopler effect, which would be a clear sign of ET. However, a normal pulse would be a sign of an evaporating black hole, which has been predicted but never observed.
This new project will run on a system called BOINC, the Berkeley Open Infrasturcture for Network Computing (yes, it's open source, to be released under the Mozilla Public License). However, BOINC is not limited to running only Astro-Pulse (the previously mentioned project) and the next generation of SETI@home, but will also be running other independent distributed computing projects. More information is available at the BOINC and SETI@home websites.
Seems like a halfway decent idea, until, of course, you ask, does my palm actually touch the mouse. At least for me, my palm doesn't touch the mouse at all. If I wanted my palm to touch the mouse, my fingers would be dragging along in front of the mouse and my arm would have to be in a poor ergonomic position. Maybe they should check how people actually hold a mouse before they start doing things like this with it.
Heh,
They used foolproof in the labs at my high school. Of course, one of the things the labs were used for was programming classes, so they had to allow programs you wrote to be able to run. So, method 1 of killing foolproof was to write a program to take it out (it took us about a week to figure out how to do this, but it didn't always work, and invariably, our instructor would just restore from image, not that we ever did any damage, just unloaded foolproof). Method 2 was, one day, somebody fell asleep on the keyboard, and accidentally disabled foolproof, so we figured out what he did (it was a short keystroke combination). Method 3 was, once somebody temporarily disabled foolproof, somebody else installed a keystroke logger and got the instructors password for foolproof. Of course, there was always the method of just overwriting the kernel, but that killed the computer, so we only did that to computers that were to be destroyed already (that was tons of fun, on the last day it would be around, one of us (me, since I knew how to do it), would overwrite the kernel), computers are all sorts of fun without kernels, and they do all sorts of funky stuff). So don't underestimate your students, they will figure out how to get around the minimal foolproof security.
Yeah, I read the little blurb, and Immediately, I started thinking, this can't be right. I am a regular dalnet user, and about a month or two ago, just before those blasted DOS attacks started, things were slow as mud, and we were trying to figure out why. Turns out, there were 254,000 people connected to JUST ONE SERVER. Of course, the DOS attacks started about a day after this, and then they were down to about 200 real connections. However, dalnet is back up and running smooth as ever these days (it hasn't been netsplitting so much anymore).
If the tasco stuff is anything like the TI calculators + 3rd party hardware + software we used in my high school physics class, it will be incredibly easy to port. Since most of the software required to decode the input was loaded onto the calculator (and was not compiled, so you could read the source), the only thing that required porting was the graph-link software, which somebody had already ported What it sounds like you have is a simple serial interface, so if you could just get the specifications for the output from tasco, i'm sure any decent programmer could port the software to linux in less than a weeks worth of time.
I believe you hit the point right on. Cryptography based on finite calculations (no matter how difficult) can at some point be broken. As long as the cardinality of the solution space is finite, it will eventually be cracked. However, should we switch to using a completely new system, with a solution space of cardinality of at least Aleph Null, many problems would be solved. However, this is far more difficult than it sounds. Most of the work going on in L2 and infinite dimensional hilbert spaces (and any other infinite dimensional spaces) is not being applied to cryptography. This is not to say that it can't be used for cryptographic purposes, it's just that much of the mathematics that goes on in these areas is very different than what the current cryptographers, discreet mathematicians, are doing.
Slashdot Mirror
This reminds me of an episode of one of the cartoons I read. Written by a Nuclear Engineering PhD at Berkeley, the strip is quite funny. Here is the one this reminds me of.
Why with a waveguide of course ;~)
(For those of you who don't know, a waveguide is basically a wire or metal box connecting two or more locations allowing EM waves to travel. One common example of a waveguide would be coax cable.)
Regarding the ancient, mystic aspect of your post, I think I can explain the history behind this some. In the old hebrew counting system, the leters were used for numbers (but it was decimal, it's just that they used letters instead of the current notation), and the letters for 18 spelled out the word for life. Hence, 18 was (and still is by some people) considered lucky.
Cohen-Tannoudji is by far the best quantum book if you want the full mathematical rigor. Feynman has several good books, both his introductory level explanatory stuff in his lectures on physics and an introduction to the path integral formulation of physics. However, based on your question, I am going to have to go with Cohen-Tannoudji.
Yes, you do in fact get an induced current. However, as demonstrated vividly by a question on my final when I was taking first semester E&M, you need somewhere on the order of 200,000 loops of wire to get enough induced current to be worthwhile from 20,000V power lines. (The exact question was, is it feasible to steal power by placing a coil between two 20,000V power transmission lines.) I'm pretty sure you don't care about the negligible effects (unless you're paranoid, or your bike is composed of 200,000 loops of wire).
Go with a flexible language as a first language. You don't want them stuck using only one programming paradigm. If possible, choose something that can do OOP, functional, logic, etc. It will serve them well down the road if they ever want to use it for anything not to be stuck in just one paradigm.
I have two different suggestions, depending on the type of keyboard you prefer.
If you prefer the laptop style keyboard (as in thin keys and very little noise from the keyboard), go with the TypeMatrix keyboard. It's a dvorak style key layout, although the keys are reprogrammable, with laptop style keys and all sorts of special keys. Additionally, the keys go straight up and down, rather than at angles. A picture is available here. My roommate uses one and loves it.
Alternatively, if you are a big fan of the "kacink" (tactile feedback) style keyboard, go with the old IBM keyboard. If you don't want it making so much noise, put a piece of foam under the keyboard. Aparently, the reason they are so noisy is the table underneath acts as a resonating board, so the foam dampens this effect.
As some have already noted, the actual wording is that the vouchers are good for ANY computer product. I propose that people use these vouchers to fund your favorite linux distribution or open source group. Let's use Microsoft's money to fund their competetion.
Human Growth Hormone is usually used to treat hormone deficiencies in children. My brother needs to take it by injection daily because he has a thyroid binding deficiency, but he's only 5 years old, and will probably stop taking it before he is 18. While it has been well studied on children, it's effects on adults are nowhere near as well studied. While some people believe it is something of a "fountain of youth," this has yet to be found to be true under any studies, and no long term safety tests have been run on adults. So, the conclusion is that you were right to be mighty suspicious of that spam you keep getting.
Just some information. There's a chain store called The Nature Store (can be found in many malls) which also has an online presencs that carries kaleidoscopes. I was looking for them when I posted, and didn't initially find them, but they have a website at http://thenaturestore.com. Of course, they won't show up if you do a search on their site, but they do in fact cary them, because I stumbled across one through google. The one I found was at http://thenaturestore.com/kidkidtoys.htm. Hope this helps.
You just have to know where to look. Most of the stores that cary more educational toys cary at least one model of kaleidoscope. You can even find places that will sell fancy kaleidoscopes with interchangable glass tubes filled with oil and whatever the other stuff is that falls by the window to create the paterns. I'm not sure if you can still find the inexpensive ones that don't use glass, but kaleidoscopes are definetely an excellent toy. Good luck in your search.
Just thought I should point out that this isn't a Jury trial. In Norway, one doesn't have the right to a jury trial. Nonetheless, your point is valid, and even more relevent, since a judge is much more likely to notice this than an untrained jury.
Yeah,
I know, most of the first level tech support people are morons. However, sometimes, if you confuse them enough and give evasive enough answers, they'll let you through to a higher level person if you ask. Some of the higher level people actually know stuff. My roommate managed to get all the way through to one of their sysadmins (we have problems establishing reliable UDP connections to some ISP's, but only if it goes through one link, and they were able to confirm where the problem was). So, the answer is, confuse the hell out of the first level people by talking about networking protocols and you might actually get through to a real sysadmin.
Actually, the heat tube works quite well. Heat tubes are used in many high end servers were cooling is critical. In fact, heat tubes can be better than the traditional heat sink/fan combo. There is a review of the athlon version of this system at http://www.tech-report.com/reviews/2002q3/shuttle- ss40g/index.x?pg=1 complete with benchmarks and comparison tests. So, if it's good enough to keep your athlon cool, it's good enough for just about anything.
This fails both under quantum physics and general relativity.
Under the quantum physics interpretation, since both the cat's feet and the buttered toast are equally likely to land on the floor, the cat-toast enters a superposition where both cat and toast are simultaneously on the floor until it is observed, at which point a radioactive particle decays, and the cat is skinned in a number of simultaneous, equally likely, yet distinct ways.
Relativity predicts that the intense attraction to the floor will, in fact, bend space-time in such a way that the floor actually is in contact with both the cat and the toast. If the cat is of the black variety, then it will thus cross its own path, generate a singularity, and vanish in a puff of logic.
The debate continues, as attempts at experimental verification have thus far failed. Dr. Kibble at Princeton's IAS said, "Look, have YOU ever tried to hold a cat still and strap some friggin' TOAST to its back?"
I can't say I came up with this (it came from a post to an article several months ago), but I have to admit, it's a great response to the classic cat/buttered toast joke.
I don't think you know how SETI@home works. First of all, it's pretty clear you don't even know how the program works. Every work unit is sent out to at least 3 computers so that results can be verified. However, since we send out so many workunits (as in, we can clog a 100 Mbit pipe, and these workunits aren't exactly huge), the system may send a workunit out more than the minumum amount of times. So a workunit may be sent out more times than necessary, but won't be sent out less times than necessary. If we aren't splitting tapes fast enough to keep up with demand, workunits will be sent to more people. We do this, because otherwise we wouldn't be able to satisfy the demands of the users, and redundancy is good. It's simply not worth our time to be going after every suspected case of cheating (as in, we have better things to do, especially since there's only a few of us). Now, on to all of the flamebait about open source. The infrastructure for the next generation of SETI@home, BOINC is open source. In fact, we would like your help on it looking for bugs and security holes. So if you want to help, visit http://boinc.ssl.berkeley.edu and help find bugs in our code. Thanks, Mike Gary Berkeley SETI project
In the mathematical sense, the dimensionality of an object refers to how many dimensions the object itself has, not the dimensionality of the ambient space. A 2-sphere, denoted S2, lives in R3. However, if you examine the surface itself, it is a 2 dimensional surface (as in, a basis for the points on the 2 sphere has only 2 elements). When doing math, dimensionality is a property of the object, not of the ambient space. When you think about this, it makes sense, since there are plenty of examples of 2 dimensional objects which cannot be found in less than 4 examples, the most common of which is the klein-bottle (think of a torus, except it intersects itself if represented in 3 dimensions, since it's made out of a mobius strip instead of an anulus).
Sometimes, scientists will also use the word "model" as something in-between, but most often it is used by engineers using well-known theories to model complex phenomena.
This reminds me of something my physics professor said in lecture on Tuesday while discussing why the Bohr model of the atom was not only bad, but unphysical. Paraphrasing him, a model is something which somewhat describes some of the data. In other words, we know it's completely wrong, but it works some of the time and is useful for understanding the actual situation.
and a physics student at UC Berkeley, I thought I would just provide a little more information for those of you who are too lazy to read the article. SETI@home has been collecting data at the Arecibo radio telescope for the last several years, and we have observed pretty much everything that is visible from that location. We are building a new data recorder that will be capable of observing broadband data/many independent narrow bands, and we will be using this to observe in Australia. We have also applied to re-observe any interesting locations we have found at Arecibo, using this new equipment.
For the last several years, we have been using the data we have gathered for several purposes, amongst which are mapping the Hydrogen distrobution in the milky way and searching for SETI. We are about to start a new project that will search for broadband pulses (which must be very short in durration), which can be encoded to have a reverse dopler effect, which would be a clear sign of ET. However, a normal pulse would be a sign of an evaporating black hole, which has been predicted but never observed.
This new project will run on a system called BOINC, the Berkeley Open Infrasturcture for Network Computing (yes, it's open source, to be released under the Mozilla Public License). However, BOINC is not limited to running only Astro-Pulse (the previously mentioned project) and the next generation of SETI@home, but will also be running other independent distributed computing projects. More information is available at the BOINC and SETI@home websites.
Seems like a halfway decent idea, until, of course, you ask, does my palm actually touch the mouse. At least for me, my palm doesn't touch the mouse at all. If I wanted my palm to touch the mouse, my fingers would be dragging along in front of the mouse and my arm would have to be in a poor ergonomic position. Maybe they should check how people actually hold a mouse before they start doing things like this with it.
Heh, They used foolproof in the labs at my high school. Of course, one of the things the labs were used for was programming classes, so they had to allow programs you wrote to be able to run. So, method 1 of killing foolproof was to write a program to take it out (it took us about a week to figure out how to do this, but it didn't always work, and invariably, our instructor would just restore from image, not that we ever did any damage, just unloaded foolproof). Method 2 was, one day, somebody fell asleep on the keyboard, and accidentally disabled foolproof, so we figured out what he did (it was a short keystroke combination). Method 3 was, once somebody temporarily disabled foolproof, somebody else installed a keystroke logger and got the instructors password for foolproof. Of course, there was always the method of just overwriting the kernel, but that killed the computer, so we only did that to computers that were to be destroyed already (that was tons of fun, on the last day it would be around, one of us (me, since I knew how to do it), would overwrite the kernel), computers are all sorts of fun without kernels, and they do all sorts of funky stuff). So don't underestimate your students, they will figure out how to get around the minimal foolproof security.
Yeah, I read the little blurb, and Immediately, I started thinking, this can't be right. I am a regular dalnet user, and about a month or two ago, just before those blasted DOS attacks started, things were slow as mud, and we were trying to figure out why. Turns out, there were 254,000 people connected to JUST ONE SERVER. Of course, the DOS attacks started about a day after this, and then they were down to about 200 real connections. However, dalnet is back up and running smooth as ever these days (it hasn't been netsplitting so much anymore).
> Be grateful it's not BSD.
;-)
Yeah, because we all know *BSD is dying
If the tasco stuff is anything like the TI calculators + 3rd party hardware + software we used in my high school physics class, it will be incredibly easy to port. Since most of the software required to decode the input was loaded onto the calculator (and was not compiled, so you could read the source), the only thing that required porting was the graph-link software, which somebody had already ported What it sounds like you have is a simple serial interface, so if you could just get the specifications for the output from tasco, i'm sure any decent programmer could port the software to linux in less than a weeks worth of time.
I believe you hit the point right on. Cryptography based on finite calculations (no matter how difficult) can at some point be broken. As long as the cardinality of the solution space is finite, it will eventually be cracked. However, should we switch to using a completely new system, with a solution space of cardinality of at least Aleph Null, many problems would be solved. However, this is far more difficult than it sounds. Most of the work going on in L2 and infinite dimensional hilbert spaces (and any other infinite dimensional spaces) is not being applied to cryptography. This is not to say that it can't be used for cryptographic purposes, it's just that much of the mathematics that goes on in these areas is very different than what the current cryptographers, discreet mathematicians, are doing.