Here's the problem, though (I've faced nearly exactly the same issue as the original poster).
1. You have programming skills, no one else in the lab does (they're all scientists with pure science backgrounds, you're the only one with a mixed engineering/science background), except the staff programmer. He is good, but also thinks there's nothing wrong with VB. Fine. Your code needs to be read, supported, and developed once you're gone.
2. You need a little experimental control program with a GUI that is reasonably easy to debug and modify, and you need it TWO MONTHS AGO.
Deploying something that meets both of these criteria is relatively straightforward if you swallow your pride and write something in VB. Hell, all of the interface card and hardware vendors provide VB example code. Doing it any other way (remember, GUI, easily changed, *yesterday*, etc.) is a heck of a lot harder. Either that, or I'm way behind in the quality of Open Source RAD tools.
Good luck to the original poster. Like many of his predecesors, I gave up and wrote the experimental control in VB. But my data analysis and primary desktop environment is still Linux.
HP didn't invent this idea by a longshot. While at MIT doing an undergrad EECS degree, we bandied about the idea of computrons (a metric of computational power, roughly equivalent to an abstracted number of instructions on a standard machine, but definitely not a direct measure of CPU cycles) and it wasn't new then, back in the early 80s.
Further, one has been able to purchase time on supercomputers at varying rates since there have been supercomputer centers (again, early 80s?) where the rates depended on time of day, requested priority, etc. While I have no direct knowledge, one can readily assume the same was true even with batch processing mainframes: pay more and your job gets put closer to the top of the stack.
So, what's new then? HP wants to factor in more variables in their pricing structure. This is a big deal?
How long would Harvard stay in business if it stopped providing value to its students?
How about an even more extreme suggestion: if Harvard ceased undergraduate education at the end of the current academic year, I'd wager they'd last at least another century or so. First, 17 billion dollars in endowment goes a long way and second, Harvard College takes up a relatively small fraction of Harvard University. Why do they have such a large endowment? Good long-term planning -- which includes tenure. Stability is key.
The primary product of the Random House publishing company is knowledge, and they manage to do it accurately and profitably, despite not guaranteeing lifetime employment to their authors, their editors, or their various and sundry support staff.
Very true, except that Random House, by-and-large, does not generate this knowledge, it merely provides the service of publication to authors. (Authors are not generally in the direct employ of the publishing house.)
Uh, no. A university is not a business. It does not sell a product or service for profit (except those institutions alluded to which sell athletics, to me an abhorrent activity incompatible with academia). Key words: for profit. There are no quarterly reports or annual reports to shareholders (although there are similar statements made to the board of trustees) which will make or break an individual's career.
As discussed in many other posts at this point the primary reason is that academic institutions are held to vastly different standards than businesses, as the primary product of academic institutions is knowledge. Thankfully, in our society, we value the accuracy and truthfullness in this knowledge enough to recognize that sometimes it is difficult to break established views with unpopular theories. Therefore the decidedly non-business idea of academic freedom is held sacrosanct.
Now, there are industrial research labs that come very close (Bell Labs, Yorktown Heights, WRL and CRL, PARC), but they work on a model that's much closer to the academic one of tenure than the standard quarterly-profit-reports driven business. They are the exception.
All of those are true, but are worthelss statements for fixing tenure. If you want to keep it, justify your answer. Employing misdirection only makes me want to classify you in with some of the lesser of your collegues.
The original posting (by El_Nofx) suggested that tenure is fundamentally broken and be abolished. My reply (as ably summarized by other respondents) was that it was on the whole very positive. The immediate parent poster (kikta) is the first in this thread to shift the focus to fixing it, which I applaud. My reply was not intended to address the problems with tenure, but, rather explore why it is a misguided idea to eliminate it.
Here, first, is one observation that will help elucidate the tenure process with which, I suspect, much of the Slashdot readership will not be familiar. Very much unlike in business or industry, a faculty job offer (the initial offer of a tenure track position, not the tenure decision) is a careful and time-consuming task. It can take many months between the initial application and the eventual offer. *Months*. It takes at least one all-day interview, and often two, which entails giving at least one formal presentation, and often at least one informal one. There are many weeks between these interviews. You are judged (at least a the institutions with which I am familiar) not only on the quality of your work, but how well you interact with the rest of the faculty and students. It is a long, careful process because the stakes are so high. The tenure decision, then, takes a similar number of months (my supervisor's candidacy lasted 6 months, and before the fact was well expected to pass) again, because the stakes are so high. It is a carefully made decision which, by and large, is made well.
Therefore, in general, tenure does not need to be fixed. However, there are definitely cases where both the granting faculty and the grantee abuse tenure. These, regrettably, form the basis for so much attention, just as those doctors who botch surgeries, are arrogant, have horrible bedside manners, form the basis of so much attention while the vast majority of doctors do their jobs with remarkable competence.
What do we do about faculties that abuse tenure (either by granting or denying it capriciously)? There is little that can be realistically done without involving the legal system, however, such faculties can be expected, over time, to self-destruct. It is a difficult thing to retain an excellent faculty over many generations; it does not just happen.
What do we do about professors who abuse tenure? There are many means of censorship which exist and vary from institution to institution. In another post, I alluded to a few; to reiterate and expand, these include salary adjustment, space allocation adjustment (if you have not been part of an academic space war, you have not seen how fractuous humans can be!), imposition of an enforced mentor or supervisor, revocation of teaching rights to graduate courses, revocation of rights to new students, revocation of institutional support for grant applications, revocation of support for publications, and so forth. Just because you cannot fire someone does not mean you cannot censure them.
These punishments are meted out with great care, however, because of the fear of attacking academic freedom, an inviolate presupposition of any academic institution of distinction. And this, I assert, is the root cause of the problems the parent post wishes to address and forms a difficult and compelling question: how can a faculty both protect itself and its students against abuses by individual professors without sacrificing academic freedom? There is no magic bullet, there is no simple answer, but I would agree with the perhaps generally held sentiment that faculties often do not apply sufficient internal pressure against the abusers.
In the cases the parent poster is, I assume, familiar with, the faculty surely was asleep at the wheel for every institution with which I am familia
Regrettably, my wit was scared out of me. My far less crafty reply amounted to the same sentiment... but damn, *should* have thought of yours! Next time.
I agree with a lot of what you say, but Harvard's tenure practices are pretty obnoxious. They don't grow their own talent - it's effectively impossible to go from associate to full professor there - but instead skim the best professors from other institutions.
I'm currently employed as a post-doc at Harvard, and inquired specifically about this when I arrived, as my impression was similar to yours. While there undoubtedly is such an effect, it is not pervasive in all departments, and to a certain degree has been the result of the Baby Boomer influx: there were just too many young faculty for a long while so very few got tenured. That's the short version of what I was told. My recent experience (in one specific department) has shown that 100% of the eligible candidates (4 for 4) received tenure in the last three years. In sum, I think the story at Harvard is more complex than the generally-held perception of the historical record.
Good luck, and watch your back. Academics is a full contact sport, sometimes.
Thanks for the luck -- I'll need it!
Re:A warning to experimenters
on
Build Your Own ECG
·
· Score: 5, Informative
PLEASE mod the parent up.
One of the reasons EKG systems (and I've used a fair handful) are expensive is that they go to extreme measures to insure that under no conditions will excessive current flow through the electrodes. (Ever wonder why hospital-grade power plugs are rated explosion-proof?)
I cannot comment on the original posting's circuit because it is slashdotted but I'm racking my brains trying to figure out how less than $10 can create a safe circuit... and it might be possible, maybe, but probably not. Consider that another posting today described an electrified jacket which delivered debilitating shocks using a 9V battery as a power source!
Also, keep in mind that just because a circuit is battery powered does not make it safe once you attach the output to an instrument (computer, oscilloscope, DAC, etc.) which is plugged in to the wall.
The parent posting eloquently raises a number of excellent points.
The general Slashdot reader might be surprized at how much influence the perceived behavior of a professor has on things like the number of committees he is assigned to, the number of students he is allowed to have, how much office and laboratory space he is allocated, and things of this ilk. While it is rare to a professor to have tenure revoked (which, to my mind, is not unlike disbarring a laywer or decertifying a doctor... extreme measures which are rare by design), there are a number of lesser punishments, if you will, which can be meted out. Tenure is not the only means of enforcement, just the most severe within academia.
When a student complains to the faculty about one member in particular, it can have far-reaching consquences. When the student writes a cogent letter to the dean of the school, it can make a big difference. But do you want to revoke tenure for someone who isn't teaching well? No, you want him to teach better. Ignoring his students? Make him pay attention. Violating some student-faculty handbook rue? Make him honor it. Revoking tenure is for eggregious cases such as when a professor sleeps with his students, misappropriates funds, or commits scientific fraud.
Tenure is definitely not a detriment however often abused by both granting institutions and grantees. Just because a mechanism is not perfect does not mean it carries no value, nor that it should be abolished.
What happens with tenure? The non-tenured junior professor works his or her ass off doing what may well be the best work of their career. Once tenured, there is undoubtedly a relaxation, but if the granting faculty have done their job, they selected someone who will continue on at a strong pace. Although my experience is clearly limited, I know of no cases where a tenured professor has relaxed to the point where he has become a burden on the institution. That, dear reader, does not mean it does not happen, just that my experiences at research universities has been otherwise.
There certainly are times when bad decisions have been made, either for or against granting tenure, but to my experience they are by and large carefully made and good ones. Harvard or MIT, for two ready examples, would not be what they are today were it not for tenure.
And what are the alternatives? Periodic contract renewal? Northeastern University has phased out nearly all of its tenured faculty in favor of part-time professors (my mother among them). I fear greatly for the long-term prospects of NU, as they will not be able to attract world-class faculty by offering renewable short-term contracts. Remember, a university is NOT a business, and there is no reason for it to be run under a business model.
Imagine the following difference in job offers: "hey, you're pretty good, stick around for 3 years, and we'll see if we still want you," or "we believe in you, here's a job for life." Which system encourages far-sighted research plans? Which system encourages making good long-term decisions rather optimizing short-term gain? Which system allows development of highly devoted faculty?
Tenure, frankly, one of the major differences between business and academia, is one of the main reasons my career is firmly on the professorial route.
The biggest detriment to the university system, in my opinion, is athletics. There is no defensible justification for big athletic programs except greed, and that has no place in the university system. Get rid of professional athletes masquerading as students, get rid of athletic scholarships, get rid of lower standards for athletes, do all this and the American university system will be driven more towards a meritocracy and *then* you'll have something. Get rid of tenure? Either the person suggesting that is just confused, works at a lower-tier school where the long-term future isn't a real concern, or is a bean counter at heart.
Try and name an AI researcher who is not a self-important jerk...
Oh, say, Rod Brooks, Tomas Lozano-Perez, Hal Abelson, Gerry Sussman, Eric Grimson, Pat Winston, Tom Knight... all at MIT/AI... need I continue?
The difference between Minsky and the rest is precisely as the first poster asserted. Having read Minsky's books, known him professionally and personally, and having taken his course, I must agree that the amount of weight placed on his words are not equal to their value. As others have observed (I forget whom and where), Minksy's original contributions were interesting ramblings at the edge of a new field which happened to pinpoint rich veins of research in some cases, and kill off valuable paths in others (think perceptrons which are, yes, in fact, very useful things, and yes, in fact, do model real neurons reasonably well, and no are not computationally impoverished unless you abide by Minsky and Papert's artifice of only single layers). In otherwords, in some cases, he got lucky, in others he fell flat. This initial success led him to continue pontification (think "Society of Mind", a book of little real contribution), while doing marginally small amounts of actual research. Rod Brooks, in contrast, has made far more, and far deeper, contributions working on his subsumption architecture.
Minsky's course (at the advanced graduate level) consists of students listening to his musings and ramblings which he often repeats through the term, since he has no syllabus, no agenda, and no apparent desire to teach. When he gives talks, they are all extemporaneous; someone like Churchill could pull that off, Minksy's stream-of-consciousness style keeps his acolytes happy, but leaves those with real thirst for knowledge quite parched. Does this not fit the accusation?
So what if Minksy thinks graduate students shouldn't be soldering robots? Does that matter? So what if the current AI field isn't following his pet projects, is he making any contributions himself? We've made tremendous strides in AI over the past decade; they just haven't been where Minksy thinks they should be, despite his questionable over-all track record. Exactly why should anyone care that much?
Re:Ripping from the source a disadvantage? Huh?
on
AAC vs. OGG vs. MP3
·
· Score: 1
I've taken one [signal processing course] (so far) and I do know about the nyquist limit, the sinc function, but I have not heard about the degradations near the limit!
You can easily see what happens if you assume a finite-time signal of, say, 4 cycles of a sinewave. Sampling at the Nyquist limit the exact phase relation between sample points and signal peaks can be adjusted so that the sampled values show anything between zero signal and full amplitude. (This much is also true for infinite length signals.) Adjusting the sinusoid so that the frequency is far below (say 1/10th) the Nyquist limit (or, equivalently, adjusting the sampling frequency upwards), you get many samples per sinusoid cycle, and the exact phase relation between waveform and sampling clock is relatively unimportant (also true for infinite signals).
Between these two extremes, the difference between infinite-time and finite-time signals becomes apparent. Say the signal is only slightly below the Nyquist limit for a given sampling frequency. If the signal is infinite-time, then some sample, somewhere, will hit the peak amplitude of the signal, constraining the reconstruction and making it accurate. If the signal is finite-time, then there is no guarantee that any of the finite number of samples will fall on the signal peak. The exact phase relationship between signal and sampling times is again important, but becomes less so as the sinusoid frequency drops away from the Nyquist limit and the chance of sampling at the cycle peak increases. The worst part about sampling near the Nyquist limit is that the errors introduced have uniform distributions (since without any prior knowledge, there's a uniform chance any given phase relation between signal and sample clock) which make them relatively difficult to model as compared to something with a Gaussian distribution.
From a purely signal processing point of view, a decent rule of thumb is that you want at least 5 sample points per cycle of the highest frequency you want to accurately reproduce. More is better.
Ripping from the source a disadvantage? Huh?
on
AAC vs. OGG vs. MP3
·
· Score: 5, Interesting
Let's see. Given the task of creating a codec de novo and the financial and political means to have access to the original source material rather than a version sent through a horribly non-linear sampling mechanism out of your control and beyond your specification, which would you choose?
I'm sure most Slashdot readers will be familiar with the Nyquist limit and understand the complete inability to represent information above the limit, but how many are familiar with the degradations that occur near the Nyquist limit when you have non-infinite signal lengths? This is why oversampling is so important. In general, if you have a signal at frequency f that you want to accurately capture, you should be sampling (by rule of thumb) at 5f or greater. If you sample at lower frequencies, the distortions in phase and amplitude are difficult to predict and statistically analyze as they tend to have uniform rather than Gaussian distributions.
So again, I re-pose the rhetorical question: given the task of creating a new codec rather than rewriting an old one, wouldn't you want to use the least-filtered signal possible as a source, especially when the extant filtering is non-linear, and be able to select by design which parts to encode and which parts to ignore? I sure would.
Thanks -- that makes more sense than the communications issue (which, presumably, could have been solved at design time by putting antennae in the wings). I recall that the shuttle executes a 90 degree roll once clear the launch tower to verify positive control of attitude... but until recently hadn't thought about the upside down issue. Is there some good source for this info (eg, web site, book, etc.)?
I wonder if the current approach will be re-visited as part of the post-Columbia re-engineering.
There's probably a really good reason, but from a naive viewpoint, the proximal cause for any chunks of foam coming off the main fuel tank being able to damage the shuttle is that during primary burn, the shuttle is slung below the tank. If the vehicle were lifted to orbit in shuttle-above-tank configuration (rotated 180 degrees along the longitudinal axis from the standard configuration), the Columbia accident might not have happened.
Anyone know why the current method (shuttle-below-tank) is used?
The MythTV Project is what you want. As often noted on Slashdot, it does nearly everything that TiVo does, and a heapload more. It's open source, and under active development... however, it's not quite at full functionality. The most recent stable release is version 0.8 and while not without some bugs seems to work quite nicely. I've paired it with a AVerTV Studio TV capture card, a Shuttle FV25 mainboard, and a Celeron 1.4 GHz processor. To my understanding, MythTV supports external tuner devices such as satellite systems. Installation/construction is straightforward but not for the faint of heart. Some RPMs exist for certain required components, but much of installation involves the "./configure; make; su; make install" cycle.
IF -- and this is a strong supposition -- you either have spare hardware laying around that's pretty strong (eg, in the GHz range rather than 100s of MHz) or have a weird bent on building your own systems, then by all means roll up your sleeves and dig in! However, if you are looking for the least expensive or easiest alternative, then buy a used or refurbished TiVo.
On the other hand, self-winding watches have been available for, oh, some decades now. They also exploit ambient vibrations, in this case movements of a human arm, as a power source (albeit with a comparitively large-scale mechanism). Furthermore, ambient office lighting levels have proved adequate to run reasonably powerful hand-held calculators for some time, and that has to be in the sub-milliwatt range (anybody know for sure?). So while in principle I agree, much of what we normally consider consumer-grade product is too power-hungry to run at ambient body or building vibration, there are some useful things that can be done quite well.
Technology Review published an article on related vibrationally-driven sensors which are intended to be used to instrument a building, powered by the small-scale vibrations present in nearly every human-built structure. Cool stuff indeed, made possible because our micromachined silicon technology has advanced to the point where under 100 microwatts is enough to do interesting things.
As anyone who is familiar with the MythTV project will attest, the feature list trumpeted by TiVo is precisely what is available for MythTV, an open source, volunteer effort (although MythTV supports more, and more diverse features). Isn't competition grand!
Each pulse is supposed to produce 1.9 kW for 0.35 s. Not a heck of a lot of energy. Imagine, for ballpark estimates, turning on your hairblower (ca 1.2 kW) for half a second. Okay, so you train that energy on a small spot (say 5 mm at the target, accounting for atmospheric dispersion). Sure it will get hot. Might even cook flesh. But drill through metal? Explode a tank? Um...
Yeah, but the "previously on Farscape" montage was FRELLING GREAT!
Want to make a difference? Send email to program@www.scifi.com. Complain. Tell them they made a huge mistake. Tell them you'll no longer be watching SciFi. Tell them.
Slashdot Mirror
Here's the problem, though (I've faced nearly exactly the same issue as the original poster).
1. You have programming skills, no one else in the lab does (they're all scientists with pure science backgrounds, you're the only one with a mixed engineering/science background), except the staff programmer. He is good, but also thinks there's nothing wrong with VB. Fine. Your code needs to be read, supported, and developed once you're gone.
2. You need a little experimental control program with a GUI that is reasonably easy to debug and modify, and you need it TWO MONTHS AGO.
Deploying something that meets both of these criteria is relatively straightforward if you swallow your pride and write something in VB. Hell, all of the interface card and hardware vendors provide VB example code. Doing it any other way (remember, GUI, easily changed, *yesterday*, etc.) is a heck of a lot harder. Either that, or I'm way behind in the quality of Open Source RAD tools.
Good luck to the original poster. Like many of his predecesors, I gave up and wrote the experimental control in VB. But my data analysis and primary desktop environment is still Linux.
Indeed, there was news about Lindows and SCO (Lindows claiming they have immunity from SCO's lawsuits due to a pre-existing agreement with Caldera) this afternoon as well. Didn't make it either.
Bill MS for your time. Send it to Accounts Payable, with all the good flags and whistles.
HP didn't invent this idea by a longshot. While at MIT doing an undergrad EECS degree, we bandied about the idea of computrons (a metric of computational power, roughly equivalent to an abstracted number of instructions on a standard machine, but definitely not a direct measure of CPU cycles) and it wasn't new then, back in the early 80s.
Further, one has been able to purchase time on supercomputers at varying rates since there have been supercomputer centers (again, early 80s?) where the rates depended on time of day, requested priority, etc. While I have no direct knowledge, one can readily assume the same was true even with batch processing mainframes: pay more and your job gets put closer to the top of the stack.
So, what's new then? HP wants to factor in more variables in their pricing structure. This is a big deal?
How long would Harvard stay in business if it stopped providing value to its students?
How about an even more extreme suggestion: if Harvard ceased undergraduate education at the end of the current academic year, I'd wager they'd last at least another century or so. First, 17 billion dollars in endowment goes a long way and second, Harvard College takes up a relatively small fraction of Harvard University. Why do they have such a large endowment? Good long-term planning -- which includes tenure. Stability is key.
The primary product of the Random House publishing company is knowledge, and they manage to do it accurately and profitably, despite not guaranteeing lifetime employment to their authors, their editors, or their various and sundry support staff.
Very true, except that Random House, by-and-large, does not generate this knowledge, it merely provides the service of publication to authors. (Authors are not generally in the direct employ of the publishing house.)
Uh, no. A university is not a business. It does not sell a product or service for profit (except those institutions alluded to which sell athletics, to me an abhorrent activity incompatible with academia). Key words: for profit. There are no quarterly reports or annual reports to shareholders (although there are similar statements made to the board of trustees) which will make or break an individual's career.
As discussed in many other posts at this point the primary reason is that academic institutions are held to vastly different standards than businesses, as the primary product of academic institutions is knowledge. Thankfully, in our society, we value the accuracy and truthfullness in this knowledge enough to recognize that sometimes it is difficult to break established views with unpopular theories. Therefore the decidedly non-business idea of academic freedom is held sacrosanct.
Now, there are industrial research labs that come very close (Bell Labs, Yorktown Heights, WRL and CRL, PARC), but they work on a model that's much closer to the academic one of tenure than the standard quarterly-profit-reports driven business. They are the exception.
All of those are true, but are worthelss statements for fixing tenure. If you want to keep it, justify your answer. Employing misdirection only makes me want to classify you in with some of the lesser of your collegues.
The original posting (by El_Nofx) suggested that tenure is fundamentally broken and be abolished. My reply (as ably summarized by other respondents) was that it was on the whole very positive. The immediate parent poster (kikta) is the first in this thread to shift the focus to fixing it, which I applaud. My reply was not intended to address the problems with tenure, but, rather explore why it is a misguided idea to eliminate it.
Here, first, is one observation that will help elucidate the tenure process with which, I suspect, much of the Slashdot readership will not be familiar. Very much unlike in business or industry, a faculty job offer (the initial offer of a tenure track position, not the tenure decision) is a careful and time-consuming task. It can take many months between the initial application and the eventual offer. *Months*. It takes at least one all-day interview, and often two, which entails giving at least one formal presentation, and often at least one informal one. There are many weeks between these interviews. You are judged (at least a the institutions with which I am familiar) not only on the quality of your work, but how well you interact with the rest of the faculty and students. It is a long, careful process because the stakes are so high. The tenure decision, then, takes a similar number of months (my supervisor's candidacy lasted 6 months, and before the fact was well expected to pass) again, because the stakes are so high. It is a carefully made decision which, by and large, is made well.
Therefore, in general, tenure does not need to be fixed. However, there are definitely cases where both the granting faculty and the grantee abuse tenure. These, regrettably, form the basis for so much attention, just as those doctors who botch surgeries, are arrogant, have horrible bedside manners, form the basis of so much attention while the vast majority of doctors do their jobs with remarkable competence.
What do we do about faculties that abuse tenure (either by granting or denying it capriciously)? There is little that can be realistically done without involving the legal system, however, such faculties can be expected, over time, to self-destruct. It is a difficult thing to retain an excellent faculty over many generations; it does not just happen.
What do we do about professors who abuse tenure? There are many means of censorship which exist and vary from institution to institution. In another post, I alluded to a few; to reiterate and expand, these include salary adjustment, space allocation adjustment (if you have not been part of an academic space war, you have not seen how fractuous humans can be!), imposition of an enforced mentor or supervisor, revocation of teaching rights to graduate courses, revocation of rights to new students, revocation of institutional support for grant applications, revocation of support for publications, and so forth. Just because you cannot fire someone does not mean you cannot censure them.
These punishments are meted out with great care, however, because of the fear of attacking academic freedom, an inviolate presupposition of any academic institution of distinction. And this, I assert, is the root cause of the problems the parent post wishes to address and forms a difficult and compelling question: how can a faculty both protect itself and its students against abuses by individual professors without sacrificing academic freedom? There is no magic bullet, there is no simple answer, but I would agree with the perhaps generally held sentiment that faculties often do not apply sufficient internal pressure against the abusers.
In the cases the parent poster is, I assume, familiar with, the faculty surely was asleep at the wheel for every institution with which I am familia
Regrettably, my wit was scared out of me. My far less crafty reply amounted to the same sentiment ... but damn, *should* have thought of yours! Next time.
I agree with a lot of what you say, but Harvard's tenure practices are pretty obnoxious. They don't grow their own talent - it's effectively impossible to go from associate to full professor there - but instead skim the best professors from other institutions.
I'm currently employed as a post-doc at Harvard, and inquired specifically about this when I arrived, as my impression was similar to yours. While there undoubtedly is such an effect, it is not pervasive in all departments, and to a certain degree has been the result of the Baby Boomer influx: there were just too many young faculty for a long while so very few got tenured. That's the short version of what I was told. My recent experience (in one specific department) has shown that 100% of the eligible candidates (4 for 4) received tenure in the last three years. In sum, I think the story at Harvard is more complex than the generally-held perception of the historical record.
Good luck, and watch your back. Academics is a full contact sport, sometimes.
Thanks for the luck -- I'll need it!
PLEASE mod the parent up.
... and it might be possible, maybe, but probably not. Consider that another posting today described an electrified jacket which delivered debilitating shocks using a 9V battery as a power source!
One of the reasons EKG systems (and I've used a fair handful) are expensive is that they go to extreme measures to insure that under no conditions will excessive current flow through the electrodes. (Ever wonder why hospital-grade power plugs are rated explosion-proof?)
I cannot comment on the original posting's circuit because it is slashdotted but I'm racking my brains trying to figure out how less than $10 can create a safe circuit
Also, keep in mind that just because a circuit is battery powered does not make it safe once you attach the output to an instrument (computer, oscilloscope, DAC, etc.) which is plugged in to the wall.
The parent posting eloquently raises a number of excellent points.
... extreme measures which are rare by design), there are a number of lesser punishments, if you will, which can be meted out. Tenure is not the only means of enforcement, just the most severe within academia.
The general Slashdot reader might be surprized at how much influence the perceived behavior of a professor has on things like the number of committees he is assigned to, the number of students he is allowed to have, how much office and laboratory space he is allocated, and things of this ilk. While it is rare to a professor to have tenure revoked (which, to my mind, is not unlike disbarring a laywer or decertifying a doctor
When a student complains to the faculty about one member in particular, it can have far-reaching consquences. When the student writes a cogent letter to the dean of the school, it can make a big difference. But do you want to revoke tenure for someone who isn't teaching well? No, you want him to teach better. Ignoring his students? Make him pay attention. Violating some student-faculty handbook rue? Make him honor it. Revoking tenure is for eggregious cases such as when a professor sleeps with his students, misappropriates funds, or commits scientific fraud.
You missed a dreaded one:
The potential career-ending mistake -- the bouncy young co-ed who comes by, closes the door, and suggests, "I'll do anything for an A, *anything*."
(Yes, it happened to me, and no, my career is intact.)
Tenure is definitely not a detriment however often abused by both granting institutions and grantees. Just because a mechanism is not perfect does not mean it carries no value, nor that it should be abolished.
What happens with tenure? The non-tenured junior professor works his or her ass off doing what may well be the best work of their career. Once tenured, there is undoubtedly a relaxation, but if the granting faculty have done their job, they selected someone who will continue on at a strong pace. Although my experience is clearly limited, I know of no cases where a tenured professor has relaxed to the point where he has become a burden on the institution. That, dear reader, does not mean it does not happen, just that my experiences at research universities has been otherwise.
There certainly are times when bad decisions have been made, either for or against granting tenure, but to my experience they are by and large carefully made and good ones. Harvard or MIT, for two ready examples, would not be what they are today were it not for tenure.
And what are the alternatives? Periodic contract renewal? Northeastern University has phased out nearly all of its tenured faculty in favor of part-time professors (my mother among them). I fear greatly for the long-term prospects of NU, as they will not be able to attract world-class faculty by offering renewable short-term contracts. Remember, a university is NOT a business, and there is no reason for it to be run under a business model.
Imagine the following difference in job offers: "hey, you're pretty good, stick around for 3 years, and we'll see if we still want you," or "we believe in you, here's a job for life." Which system encourages far-sighted research plans? Which system encourages making good long-term decisions rather optimizing short-term gain? Which system allows development of highly devoted faculty?
Tenure, frankly, one of the major differences between business and academia, is one of the main reasons my career is firmly on the professorial route.
The biggest detriment to the university system, in my opinion, is athletics. There is no defensible justification for big athletic programs except greed, and that has no place in the university system. Get rid of professional athletes masquerading as students, get rid of athletic scholarships, get rid of lower standards for athletes, do all this and the American university system will be driven more towards a meritocracy and *then* you'll have something. Get rid of tenure? Either the person suggesting that is just confused, works at a lower-tier school where the long-term future isn't a real concern, or is a bean counter at heart.
Try and name an AI researcher who is not a self-important jerk...
... all at MIT/AI ... need I continue?
Oh, say, Rod Brooks, Tomas Lozano-Perez, Hal Abelson, Gerry Sussman, Eric Grimson, Pat Winston, Tom Knight
The difference between Minsky and the rest is precisely as the first poster asserted. Having read Minsky's books, known him professionally and personally, and having taken his course, I must agree that the amount of weight placed on his words are not equal to their value. As others have observed (I forget whom and where), Minksy's original contributions were interesting ramblings at the edge of a new field which happened to pinpoint rich veins of research in some cases, and kill off valuable paths in others (think perceptrons which are, yes, in fact, very useful things, and yes, in fact, do model real neurons reasonably well, and no are not computationally impoverished unless you abide by Minsky and Papert's artifice of only single layers). In otherwords, in some cases, he got lucky, in others he fell flat. This initial success led him to continue pontification (think "Society of Mind", a book of little real contribution), while doing marginally small amounts of actual research. Rod Brooks, in contrast, has made far more, and far deeper, contributions working on his subsumption architecture.
Minsky's course (at the advanced graduate level) consists of students listening to his musings and ramblings which he often repeats through the term, since he has no syllabus, no agenda, and no apparent desire to teach. When he gives talks, they are all extemporaneous; someone like Churchill could pull that off, Minksy's stream-of-consciousness style keeps his acolytes happy, but leaves those with real thirst for knowledge quite parched. Does this not fit the accusation?
So what if Minksy thinks graduate students shouldn't be soldering robots? Does that matter? So what if the current AI field isn't following his pet projects, is he making any contributions himself? We've made tremendous strides in AI over the past decade; they just haven't been where Minksy thinks they should be, despite his questionable over-all track record. Exactly why should anyone care that much?
I've taken one [signal processing course] (so far) and I do know about the nyquist limit, the sinc function, but I have not heard about the degradations near the limit!
You can easily see what happens if you assume a finite-time signal of, say, 4 cycles of a sinewave. Sampling at the Nyquist limit the exact phase relation between sample points and signal peaks can be adjusted so that the sampled values show anything between zero signal and full amplitude. (This much is also true for infinite length signals.) Adjusting the sinusoid so that the frequency is far below (say 1/10th) the Nyquist limit (or, equivalently, adjusting the sampling frequency upwards), you get many samples per sinusoid cycle, and the exact phase relation between waveform and sampling clock is relatively unimportant (also true for infinite signals).
Between these two extremes, the difference between infinite-time and finite-time signals becomes apparent. Say the signal is only slightly below the Nyquist limit for a given sampling frequency. If the signal is infinite-time, then some sample, somewhere, will hit the peak amplitude of the signal, constraining the reconstruction and making it accurate. If the signal is finite-time, then there is no guarantee that any of the finite number of samples will fall on the signal peak. The exact phase relationship between signal and sampling times is again important, but becomes less so as the sinusoid frequency drops away from the Nyquist limit and the chance of sampling at the cycle peak increases. The worst part about sampling near the Nyquist limit is that the errors introduced have uniform distributions (since without any prior knowledge, there's a uniform chance any given phase relation between signal and sample clock) which make them relatively difficult to model as compared to something with a Gaussian distribution.
From a purely signal processing point of view, a decent rule of thumb is that you want at least 5 sample points per cycle of the highest frequency you want to accurately reproduce. More is better.
Let's see. Given the task of creating a codec de novo and the financial and political means to have access to the original source material rather than a version sent through a horribly non-linear sampling mechanism out of your control and beyond your specification, which would you choose?
I'm sure most Slashdot readers will be familiar with the Nyquist limit and understand the complete inability to represent information above the limit, but how many are familiar with the degradations that occur near the Nyquist limit when you have non-infinite signal lengths? This is why oversampling is so important. In general, if you have a signal at frequency f that you want to accurately capture, you should be sampling (by rule of thumb) at 5f or greater. If you sample at lower frequencies, the distortions in phase and amplitude are difficult to predict and statistically analyze as they tend to have uniform rather than Gaussian distributions.
So again, I re-pose the rhetorical question: given the task of creating a new codec rather than rewriting an old one, wouldn't you want to use the least-filtered signal possible as a source, especially when the extant filtering is non-linear, and be able to select by design which parts to encode and which parts to ignore? I sure would.
Thanks -- that makes more sense than the communications issue (which, presumably, could have been solved at design time by putting antennae in the wings). I recall that the shuttle executes a 90 degree roll once clear the launch tower to verify positive control of attitude ... but until recently hadn't thought about the upside down issue. Is there some good source for this info (eg, web site, book, etc.)?
I wonder if the current approach will be re-visited as part of the post-Columbia re-engineering.
There's probably a really good reason, but from a naive viewpoint, the proximal cause for any chunks of foam coming off the main fuel tank being able to damage the shuttle is that during primary burn, the shuttle is slung below the tank. If the vehicle were lifted to orbit in shuttle-above-tank configuration (rotated 180 degrees along the longitudinal axis from the standard configuration), the Columbia accident might not have happened.
Anyone know why the current method (shuttle-below-tank) is used?
The guy that did the work (Phoenix AZ) is an artist that specializes in jewelry ...
Name? Address? Would love to give him more business.
The MythTV Project is what you want. As often noted on Slashdot, it does nearly everything that TiVo does, and a heapload more. It's open source, and under active development ... however, it's not quite at full functionality. The most recent stable release is version 0.8 and while not without some bugs seems to work quite nicely. I've paired it with a AVerTV Studio TV capture card, a Shuttle FV25 mainboard, and a Celeron 1.4 GHz processor. To my understanding, MythTV supports external tuner devices such as satellite systems. Installation/construction is straightforward but not for the faint of heart. Some RPMs exist for certain required components, but much of installation involves the "./configure; make; su; make install" cycle.
IF -- and this is a strong supposition -- you either have spare hardware laying around that's pretty strong (eg, in the GHz range rather than 100s of MHz) or have a weird bent on building your own systems, then by all means roll up your sleeves and dig in! However, if you are looking for the least expensive or easiest alternative, then buy a used or refurbished TiVo.
On the other hand, self-winding watches have been available for, oh, some decades now. They also exploit ambient vibrations, in this case movements of a human arm, as a power source (albeit with a comparitively large-scale mechanism). Furthermore, ambient office lighting levels have proved adequate to run reasonably powerful hand-held calculators for some time, and that has to be in the sub-milliwatt range (anybody know for sure?). So while in principle I agree, much of what we normally consider consumer-grade product is too power-hungry to run at ambient body or building vibration, there are some useful things that can be done quite well.
Technology Review published an article on related vibrationally-driven sensors which are intended to be used to instrument a building, powered by the small-scale vibrations present in nearly every human-built structure. Cool stuff indeed, made possible because our micromachined silicon technology has advanced to the point where under 100 microwatts is enough to do interesting things.
As anyone who is familiar with the MythTV project will attest, the feature list trumpeted by TiVo is precisely what is available for MythTV, an open source, volunteer effort (although MythTV supports more, and more diverse features). Isn't competition grand!
Each pulse is supposed to produce 1.9 kW for 0.35 s. Not a heck of a lot of energy. Imagine, for ballpark estimates, turning on your hairblower (ca 1.2 kW) for half a second. Okay, so you train that energy on a small spot (say 5 mm at the target, accounting for atmospheric dispersion). Sure it will get hot. Might even cook flesh. But drill through metal? Explode a tank? Um ...
My vote is: Hoax.
Yeah, but the "previously on Farscape" montage was FRELLING GREAT!
Want to make a difference? Send email to program@www.scifi.com. Complain. Tell them they made a huge mistake. Tell them you'll no longer be watching SciFi. Tell them.