Convection is only one form of heat transfer. The other two are conduction and radition. Our sun's energy, for example, reaches us primarily via radiation.
I think the most interesting thing about NASA's use of computers is that they don't allow any dynamic memory allocation. That makes certain things easier (e.g., squashing bugs), and other things much, much harder (e.g., writing a useful program).
I agree completely. It is very important as an academic to ensure that this instructor's behavior is not tolerated. Your school most likely has a well-defined policy for behavior, and what many people often fail to realize is that this policy cuts both ways. It lays out expected behavior for both students and teachers.
When I was a college sophomore, I took an introductory geosciences class to fill a gen-ed requirement. Now, most of the people in this class had pinned their hopes on a curve in this class, but I enjoyed the subject material, and in general, I took my studies very seriously.
However, around the time of the midterm exam, I came down with a horrible stomach bug, and was unable to attend class. I contacted the professor ahead of the exam, and had even made the effort to get a doctor's note. But the professor actually had the gall to tell me "tough luck, kid" in writing. I wrote a letter back to the professor, copying both my advisor and the Dean of Students, citing portions of the Undergraduate Code of Conduct (the "arbitrary and capricious" part was the money quote), and pasting this nice , little "tough luck, kid" part into the letter.
Within 24 hours the professor had scheduled a time for me to do a make-up exam.
It may seem like students often get the shit-end of the stick, but keep in mind, these people work for you, even if they don't always act like it.
Wait, you're telling me that I can watch Al Kaprielian in HD now? Awesome! I'll have to go out and get a TV (this is, at the moment, a Netflix-on-computer-only household). High pressha!!!
On Ubuntu you can double-click on the.deb file just like you would with a.msi on Windows. I've occasionally done this for some third-party software that is not in a repo. I believe you can do the same with RPMs on RedHat-type distros; IIRC, this is how I installed StorNext on our CentOS machines.
I suspect that Linux types would be opposed to autorun on principle.
The Kensington Expert Mouse is a trackball. That you couldn't be bothered to look that up, but that you could be bothered to express your dissatisfaction about it is, frankly, beyond comprehension.
Holy shit. Are you running a factory or something?
I know I'm asking this on a website where people's hobbies tend to consume lots of electricity (e.g., people here are talking about running their plasma screen TVs off of generators), but seriously, how hard is it for people to go without power for awhile? I understand the pipes-bursting thing (and not-so-fondly recall waking up with my father in the middle of the night to thaw pipes with a blowtorch), but 20kW? 200A transfer switch? I completely don't mean this as a troll, but how is that necessary?
I am not reading the article, nor clicking through all the stupid pages filled with ads, because I already know the answers.
The best mouse is the one I've had since sometime in 1998 or 1999: Microsoft IntelliMouse Optical USB. It's continued to operate flawlessly for the past 10 years, and was well worth the $75 I paid for it at the time. Five buttons, and a scroll wheel when such things were considered novelties. I regard the yellowing plastic with amusement, since most computer peripherals don't last anywhere near as long (OTOH, it is sitting next to an Apple Extended II keyboard, which is at least 5 years older).
That said, this is not meant to imply that mice are the best pointing devices! Being somewhat of a hardcore computer user (typing all day, and... ok, most nights, too), I've developed a bit of a pain in my mousing elbow. This was all promptly eliminated by the purchase of a Kensington Expert Mouse, which really is the best damn input device I've ever used. The scroll ring is especially cool, because it can zip through long webpages much faster than a scroll wheel can. I should have gotten one years ago.
I have to agree. In the ~8 years that I've been using CFLs, I've only had one go out: the one I dropped and smashed on the floor. And the impact on my power bill is immediately noticable after I swap out the incandescents.
In that time, I've been in 4 different apartments, and I always unscrew and take my CFLs with me. With the exception that the older ones tend to turn on a little more slowly than the newer ones, they still work just fine. I just moved into the fourth apartment a few weeks ago, and repeated this procedure, so it's fresh in my mind.
Well, I currently have an IBM Model M connected to my iMac at work (typing on it right now). It doesn't get less Mac friendly than that, and it works fine. Strangely, I have an old ADB Apple Extended II Keyboard connected to my Linux machine at home, and that works fine, too. I have an old AT keyboard kicking around the office (attached to ancient PBX computer)... maybe someday I'll see if I can connect that to my Mac, too.
Discrete Mathematics with Applications by Suzanna Epp. This book was a godsend in my discrete math class, which was taught by a Chinese prof who had recently acquired English, and who chose what must be the most god-awful textbook I've ever read. It's a favorite casual-reading book of mine.
And in the "useful" category, Friedl's Mastering Regular Expressions is my #1 most referred-to book. Totally dog-eared. And I think I've only mastered about a 1/3 of the book.
What do you mean by "weaker access controls"? Do you mean ACLs as opposed to POSIX permissions? IIRC, the argument was: ACLs are confusing, and anything that is confusing is bad for security. As someone who has to admin ACLs on Linux systems, I have to agree-- the extra complexity usually isn't worth it, and most of our filesharing uses traditional POSIX permissions.
If you mean that they haven't paid attention to local exploits, you're mistaken. They take all of these things seriously, and changes to their memory-allocation routines and the inclusion of memory protection in the base compiler shows this. But it doesn't make a lot of sense to spend time putting arbitrary obstacles in front of a user who is already privileged. You're already screwed.
Bob Beck showed a PF feature at BSDCon several years ago that "stuttered" the connection speed for abusive users-- you can define particular behavioral patterns to watch for in your pf.conf, or even have a log-watching program modify PF's tables dynamically based on something it sees in a logfile. OpenBSD's spamd uses such a feature, and the result has been that spammers tend to avoid these "tarpits" because they spend a lot of time stuck in them when they could be blasting spam out elsewhere. You end up seeing many spammers dropping connections after 10 seconds or so. We've been running with this feature on our site for a couple years now, and it works beautifully. Among people running OpenBSD firewalls-- this is a pretty popular feature. That may be the cause of the avoidance of OpenBSD sshds.
Re:My recollection differs from the book
on
Trick or Treatment
·
· Score: 2, Interesting
My own vague recollection matches yours. On the commercial drug front, tailored drugs are currently the subject of intense research. We now have the ability to quickly sequence a person's entire genome within a reasonable timeframe. What is not well understood, however, is how those genes get expressed, and how that expression interacts with various drugs. The discovery of [what is now being called] the epigenome essentially adds at least an order of magnitude more complexity into biochemical processes in your body, and grappling with that complexity will be key to developing tailored drugs.
Re:Chiropractic treatment worked for me
on
Trick or Treatment
·
· Score: 2, Insightful
The reason, I suspect, is that some parts of chiropractic, e.g., massage, have actual therapeutic value. One of the reasons why people are so unhappy with traditional doctors is that a doctor will look at them, maybe touch a spot here and there, take a photograph, and then conclude: "there is nothing wrong with you". But this phrase means something quite different to a doctor than a layperson.
A layperson _knows_ there's something wrong. It hurts! What they do not know, and what the doctor is telling them in a terse and somewhat cryptic way is: there is no permanent damage. A great deal of back pain is caused by strain or damage to skeletal muscle, and it is painful. But it will heal.
A person who visits a chiropractor gets instant satisfaction. Your chiropractor may examine you, proclaim, "Ah, a subluxation!" (which sounds at least, quasi-scientific), and immediately proceed to push and prod-- essential massage-- you, until you feel better. People walk out with the good feeling you get after a massage, plus the fact that their "Doctor" did _something_, and think: my M.D. was full of shit!
Scientific American had a lengthy article examining why chiropractic was so popular, that you may find interesting. (I can't seem to find it-- it was not the SciAm Frontiers show on PBS about the same subject)
Generally speaking, chiropractic is benign and often helpful, if otherwise completely hogwash. But you have to be careful-- the practitioners of alternative medicine have a worldview that is not at all based in any kind of rigorous method-- and as a result, they can cause real harm.
The lack of communication between M.D.s and patients is a real problem, and needs to be rectified. My girlfriend, who is near the end of her medical schooling, speaks about this often with me. Unfortunately, doctors are under such time pressure that this leads to a serious lack of bedside manner. What results is a crisis in faith in their expertise among laypeople.
There's actually a pretty good introduction to the semantic web in this month's Communications of the ACM. You're right when you say that the semantic web is, as yet, mostly unrealized. But it has huge potential.
Relational databases were in the same position in the late 60's/early 70's. We needed ways to combine and extract information automatically with a simple and expressive language. Relational database management systems, combined with SQL were the result of that, and they were a smashing success. They are now a standard business tool. The key to that success is essentially the role that the database's ontology plays in an RDBMS.
Having spent a lot of time professionally and academically working with and studying database technologies, most of the work is in understanding your data. Specifically, building a data model. A well-built data model is essentially an ontology. There are various techniques used to make sure that your can be handled automatically, mainly by normalization. This requires a tremendous amount of work on the part of the database designer, but the end result is that the end-user can query this data in fairly simple terms and get an enormous richness of data, sometimes in ways that even the database designer did not foresee. I think the success of database systems is what is driving a lot of the work in building the semantic web.
So you can see-- the big problem with the web is not just that data is not just unstructured, but that there are no standardized ontologies out there. RDF is an attempt to solve some of these problems simply, because you can embed your ontology, but it may be well off. On the other hand, if new tools make structuring data very easy or natural, people may be motivated to do the extra work because they'll personally benefit from it. For example, many people annotate or organize their photo collections naturally, so that they can share them with others. A smart photo gallery software writer may be able to come along and take advantage of that behavior to further enhance the meaning of that data.
Most of my experience was hiking from Georgia to Maine on at the AT. I was in contact with lots of people, especially southerners, since the majority of people hiking on the trail are from the South. I figure that the amount of time I spent south of the Mason-Dixon line to be about 4 months. But I also have family in the south, and I've had quite a lot of contact with them-- and they love to bring up these kinds of conversation in particular.
But another poster pointed out that it may have been my northern accent that threw people off. This is entirely possible, since I was frequently referred to as a "Yank", even by friends. This didn't bother me in the slightest, but it was clear that there was a lot of historical resentment behind the utterance of that word.
BTW, I didn't mean to denigrate southern people in any way-- I just meant to point out that one's appreciation of humor is firmly seated in one's cultural context. In general, northerners and southerners are not that different, but there are some occasional gotchas. Like, it is completely unacceptable in the north-- or at least in Boston-- to speak to someone in the checkout line like you know them. But people tend to be a bit more friendly in the south.
Slashdot Mirror
Convection is only one form of heat transfer. The other two are conduction and radition. Our sun's energy, for example, reaches us primarily via radiation.
I think the most interesting thing about NASA's use of computers is that they don't allow any dynamic memory allocation. That makes certain things easier (e.g., squashing bugs), and other things much, much harder (e.g., writing a useful program).
seconded
I agree completely. It is very important as an academic to ensure that this instructor's behavior is not tolerated. Your school most likely has a well-defined policy for behavior, and what many people often fail to realize is that this policy cuts both ways. It lays out expected behavior for both students and teachers.
When I was a college sophomore, I took an introductory geosciences class to fill a gen-ed requirement. Now, most of the people in this class had pinned their hopes on a curve in this class, but I enjoyed the subject material, and in general, I took my studies very seriously.
However, around the time of the midterm exam, I came down with a horrible stomach bug, and was unable to attend class. I contacted the professor ahead of the exam, and had even made the effort to get a doctor's note. But the professor actually had the gall to tell me "tough luck, kid" in writing. I wrote a letter back to the professor, copying both my advisor and the Dean of Students, citing portions of the Undergraduate Code of Conduct (the "arbitrary and capricious" part was the money quote), and pasting this nice , little "tough luck, kid" part into the letter.
Within 24 hours the professor had scheduled a time for me to do a make-up exam.
It may seem like students often get the shit-end of the stick, but keep in mind, these people work for you, even if they don't always act like it.
The article just has some annoying CGI.
The whole reason I got a Slashdot account was to filter him out. You can do the same with ScuttleMonkey:
Preferences -> Index -> Authors
Uncheck "ScuttleMonkey" and click "save".
Enjoy.
Wait, you're telling me that I can watch Al Kaprielian in HD now? Awesome! I'll have to go out and get a TV (this is, at the moment, a Netflix-on-computer-only household). High pressha!!!
That's fine, assuming you want a mouthful of sperm.
/me ducks
On Ubuntu you can double-click on the .deb file just like you would with a .msi on Windows. I've occasionally done this for some third-party software that is not in a repo. I believe you can do the same with RPMs on RedHat-type distros; IIRC, this is how I installed StorNext on our CentOS machines.
I suspect that Linux types would be opposed to autorun on principle.
The Kensington Expert Mouse is a trackball. That you couldn't be bothered to look that up, but that you could be bothered to express your dissatisfaction about it is, frankly, beyond comprehension.
Interesting. Thanks for the links.
Holy shit. Are you running a factory or something?
I know I'm asking this on a website where people's hobbies tend to consume lots of electricity (e.g., people here are talking about running their plasma screen TVs off of generators), but seriously, how hard is it for people to go without power for awhile? I understand the pipes-bursting thing (and not-so-fondly recall waking up with my father in the middle of the night to thaw pipes with a blowtorch), but 20kW? 200A transfer switch? I completely don't mean this as a troll, but how is that necessary?
Phew, good thing the forests have you around!
I am not reading the article, nor clicking through all the stupid pages filled with ads, because I already know the answers. The best mouse is the one I've had since sometime in 1998 or 1999: Microsoft IntelliMouse Optical USB. It's continued to operate flawlessly for the past 10 years, and was well worth the $75 I paid for it at the time. Five buttons, and a scroll wheel when such things were considered novelties. I regard the yellowing plastic with amusement, since most computer peripherals don't last anywhere near as long (OTOH, it is sitting next to an Apple Extended II keyboard, which is at least 5 years older).
That said, this is not meant to imply that mice are the best pointing devices! Being somewhat of a hardcore computer user (typing all day, and... ok, most nights, too), I've developed a bit of a pain in my mousing elbow. This was all promptly eliminated by the purchase of a Kensington Expert Mouse, which really is the best damn input device I've ever used. The scroll ring is especially cool, because it can zip through long webpages much faster than a scroll wheel can. I should have gotten one years ago.
I have to agree. In the ~8 years that I've been using CFLs, I've only had one go out: the one I dropped and smashed on the floor. And the impact on my power bill is immediately noticable after I swap out the incandescents.
In that time, I've been in 4 different apartments, and I always unscrew and take my CFLs with me. With the exception that the older ones tend to turn on a little more slowly than the newer ones, they still work just fine. I just moved into the fourth apartment a few weeks ago, and repeated this procedure, so it's fresh in my mind.
Well, I currently have an IBM Model M connected to my iMac at work (typing on it right now). It doesn't get less Mac friendly than that, and it works fine. Strangely, I have an old ADB Apple Extended II Keyboard connected to my Linux machine at home, and that works fine, too. I have an old AT keyboard kicking around the office (attached to ancient PBX computer)... maybe someday I'll see if I can connect that to my Mac, too.
Discrete Mathematics with Applications by Suzanna Epp. This book was a godsend in my discrete math class, which was taught by a Chinese prof who had recently acquired English, and who chose what must be the most god-awful textbook I've ever read. It's a favorite casual-reading book of mine.
And in the "useful" category, Friedl's Mastering Regular Expressions is my #1 most referred-to book. Totally dog-eared. And I think I've only mastered about a 1/3 of the book.
Apparently Slashdot mods fail the gullibility test.
I have a better one:
"Please RESTART your computer before you go home. You read that right: restart, NOT shutdown."
I'm all for removing users from the equation somehow. I don't mean in this case. I mean, in general.
OpenBSD computer:
$ telnet openbsdhost.local 22
Trying openbsdhost.local...
Connected to openbsdhost.local.
Escape character is '^]'.
SSH-2.0-OpenSSH_5.1
^]
telnet> quit
Connection closed.
Any other computer running SSH:
$ telnet linuxhost.local 22
Trying linuxhost.local...
Connected to linuxhost.local.
Escape character is '^]'.
SSH-1.99-OpenSSH_3.9p1
^]
telnet> quit
Connection closed.
The "p" in the OpenSSH connection hello message stands for "portable version".
What do you mean by "weaker access controls"? Do you mean ACLs as opposed to POSIX permissions? IIRC, the argument was: ACLs are confusing, and anything that is confusing is bad for security. As someone who has to admin ACLs on Linux systems, I have to agree-- the extra complexity usually isn't worth it, and most of our filesharing uses traditional POSIX permissions.
If you mean that they haven't paid attention to local exploits, you're mistaken. They take all of these things seriously, and changes to their memory-allocation routines and the inclusion of memory protection in the base compiler shows this. But it doesn't make a lot of sense to spend time putting arbitrary obstacles in front of a user who is already privileged. You're already screwed.
Bob Beck showed a PF feature at BSDCon several years ago that "stuttered" the connection speed for abusive users-- you can define particular behavioral patterns to watch for in your pf.conf, or even have a log-watching program modify PF's tables dynamically based on something it sees in a logfile. OpenBSD's spamd uses such a feature, and the result has been that spammers tend to avoid these "tarpits" because they spend a lot of time stuck in them when they could be blasting spam out elsewhere. You end up seeing many spammers dropping connections after 10 seconds or so. We've been running with this feature on our site for a couple years now, and it works beautifully. Among people running OpenBSD firewalls-- this is a pretty popular feature. That may be the cause of the avoidance of OpenBSD sshds.
My own vague recollection matches yours. On the commercial drug front, tailored drugs are currently the subject of intense research. We now have the ability to quickly sequence a person's entire genome within a reasonable timeframe. What is not well understood, however, is how those genes get expressed, and how that expression interacts with various drugs. The discovery of [what is now being called] the epigenome essentially adds at least an order of magnitude more complexity into biochemical processes in your body, and grappling with that complexity will be key to developing tailored drugs.
The reason, I suspect, is that some parts of chiropractic, e.g., massage, have actual therapeutic value. One of the reasons why people are so unhappy with traditional doctors is that a doctor will look at them, maybe touch a spot here and there, take a photograph, and then conclude: "there is nothing wrong with you". But this phrase means something quite different to a doctor than a layperson.
A layperson _knows_ there's something wrong. It hurts! What they do not know, and what the doctor is telling them in a terse and somewhat cryptic way is: there is no permanent damage. A great deal of back pain is caused by strain or damage to skeletal muscle, and it is painful. But it will heal.
A person who visits a chiropractor gets instant satisfaction. Your chiropractor may examine you, proclaim, "Ah, a subluxation!" (which sounds at least, quasi-scientific), and immediately proceed to push and prod-- essential massage-- you, until you feel better. People walk out with the good feeling you get after a massage, plus the fact that their "Doctor" did _something_, and think: my M.D. was full of shit!
Scientific American had a lengthy article examining why chiropractic was so popular, that you may find interesting. (I can't seem to find it-- it was not the SciAm Frontiers show on PBS about the same subject)
Generally speaking, chiropractic is benign and often helpful, if otherwise completely hogwash. But you have to be careful-- the practitioners of alternative medicine have a worldview that is not at all based in any kind of rigorous method-- and as a result, they can cause real harm.
The lack of communication between M.D.s and patients is a real problem, and needs to be rectified. My girlfriend, who is near the end of her medical schooling, speaks about this often with me. Unfortunately, doctors are under such time pressure that this leads to a serious lack of bedside manner. What results is a crisis in faith in their expertise among laypeople.
There's actually a pretty good introduction to the semantic web in this month's Communications of the ACM. You're right when you say that the semantic web is, as yet, mostly unrealized. But it has huge potential.
Relational databases were in the same position in the late 60's/early 70's. We needed ways to combine and extract information automatically with a simple and expressive language. Relational database management systems, combined with SQL were the result of that, and they were a smashing success. They are now a standard business tool. The key to that success is essentially the role that the database's ontology plays in an RDBMS.
Having spent a lot of time professionally and academically working with and studying database technologies, most of the work is in understanding your data. Specifically, building a data model. A well-built data model is essentially an ontology. There are various techniques used to make sure that your can be handled automatically, mainly by normalization. This requires a tremendous amount of work on the part of the database designer, but the end result is that the end-user can query this data in fairly simple terms and get an enormous richness of data, sometimes in ways that even the database designer did not foresee. I think the success of database systems is what is driving a lot of the work in building the semantic web.
So you can see-- the big problem with the web is not just that data is not just unstructured, but that there are no standardized ontologies out there. RDF is an attempt to solve some of these problems simply, because you can embed your ontology, but it may be well off. On the other hand, if new tools make structuring data very easy or natural, people may be motivated to do the extra work because they'll personally benefit from it. For example, many people annotate or organize their photo collections naturally, so that they can share them with others. A smart photo gallery software writer may be able to come along and take advantage of that behavior to further enhance the meaning of that data.
Most of my experience was hiking from Georgia to Maine on at the AT. I was in contact with lots of people, especially southerners, since the majority of people hiking on the trail are from the South. I figure that the amount of time I spent south of the Mason-Dixon line to be about 4 months. But I also have family in the south, and I've had quite a lot of contact with them-- and they love to bring up these kinds of conversation in particular.
But another poster pointed out that it may have been my northern accent that threw people off. This is entirely possible, since I was frequently referred to as a "Yank", even by friends. This didn't bother me in the slightest, but it was clear that there was a lot of historical resentment behind the utterance of that word.
BTW, I didn't mean to denigrate southern people in any way-- I just meant to point out that one's appreciation of humor is firmly seated in one's cultural context. In general, northerners and southerners are not that different, but there are some occasional gotchas. Like, it is completely unacceptable in the north-- or at least in Boston-- to speak to someone in the checkout line like you know them. But people tend to be a bit more friendly in the south.