Domain: mit.edu
Stories and comments across the archive that link to mit.edu.
Comments · 7,673
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Prof. Hal Abelson
Is this the same Hal Abelson of SICP fame?
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Re:Multics
Yep. The last Multics installation closed in 2000, but they released the source under the MIT license in 2007.
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Re:Way cool
1) the recycleables we send them are for various reasons. A) we don't have a facility to reprocess ALL kinds of plastics, b) they have lower standards for what much of that is reused for, and a lot of it actually does not come back to us, c) we have a shrtage of landfill; not because we don;t want to build more, but because we actually do not have enough trash to fill them, they are actually HIGHLY profitable http://msl1.mit.edu/TPP12399/casenotes/recyc.pdf.
My local recycling center processes over 80% of the plastics taken in into reusable products. Most of what is not recycled are type 5 and 7 plastics, which both have low petroleum content, and high chlorine content, and would be virtually useless to this plastic to oil process, and it is the bulk of this plastic that we send overseas, a lot of which is processed into plastic boards, insulation filler, and other substances that are made from shredded plastics. Type 1, 2, and 6 plastics are recylced right here, most of which is sent to our local bottling plants and never leaves the state (unless the newly filled bottle does).Doty has a proven process, they just don't have a facility. This has been proven in lab scale system, and the mathematics and physics are all known variables. There's no guesswork, it;s not vaporware. They're in the works to have a facility operational in less than 3 years. They are working with multiple investors. This will happen.
It IS carbon nuetral. The CO2 input into the gas is from already expelled CO2. They are not using any stored source of CO2 in the process, so they are not introducing CO2 that would not already have been released. That is the scientific definition of carbon nuetral! The energy in the system is entirely from wind. No additional oil or energy is required, nor does it remove from the economy another product that reqwuires more oil.
If you turn plastic into oil, plastic that was previously recycled into other plastic, now you need to drill for MORE OIL, that is clearly not the same, and clearly not carbon nuetral. unl;ess you can also reduce the demand for plastic and close the loop, this is not a green process, in fact, based on the math it will actually increase the pace and demand for oil. Every piece of plastic we throw in a landfill DOES NOT GET BURNED, and thus releases no CO2. Though it;s bad for the oil supply industry, banning plastic recyling and ENFORCING disposal actually puts more oil back in the gound and could be considdered carbon negative, since oil dis a fixed comodity, and that meansd we'd run out sooner and burn less of it, forcing the adoption af an alternative sooner with lower CO2 counts in the air at that time.
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Re:Speaking as a chemist
What does "that's simply because the electrons follow wave trajectories" mean?
Well, in classical motion, trajectories are straight lines. Add in gravity, and the lines become curves. At the quantum level, though, that doesn't apply (or rather, isn't dominant), but neither does the notion that particles *become* waves. Instead, they follow wave trajectories, rather than straight lines. Check out this article in arXiv: Understanding Bohmian mechanics: A dialogue, good for newcomers asking these sorts of questions. This site has some good illustrations of the trajectories, which were copied from an illustration on the site I first linked you to. Here's a paper from Physics Letters A will a better illustration of the trajectories (page 209).
That's precisely what "collapsing the wave function" means mathematically. We don't have a handle on what it means physically.
That arXiv article covers exactly that. Check it out.
I cannot speak to the polarizing label experiments. I'd be interested in Prof. Norsen's take on it. I'll send him a question and see if he answers. He's been quick with responses before, so I'm hopeful. -
Re:20 miles up is NOT space
It seems like MIT has been releasing a lot of 'news' that concentrates on making technology available more cheaply. I don't know if it is a change in technology focus, the fact that so many of their students seem to come from foreign countries, or they have a social conscience, but they have recently discussed a cheap solar concentrator, peanut sheller, a low cost water purification, and they host the International Development Design Summit and IDEAS.
No, this is nothing ground-breaking technology wise, but they are cleverly using inexpensive technology to provide capability to a wider range of people. And that's a good thing. -
Re:20 miles up is NOT space
It seems like MIT has been releasing a lot of 'news' that concentrates on making technology available more cheaply. I don't know if it is a change in technology focus, the fact that so many of their students seem to come from foreign countries, or they have a social conscience, but they have recently discussed a cheap solar concentrator, peanut sheller, a low cost water purification, and they host the International Development Design Summit and IDEAS.
No, this is nothing ground-breaking technology wise, but they are cleverly using inexpensive technology to provide capability to a wider range of people. And that's a good thing. -
Re:20 miles up is NOT space
It seems like MIT has been releasing a lot of 'news' that concentrates on making technology available more cheaply. I don't know if it is a change in technology focus, the fact that so many of their students seem to come from foreign countries, or they have a social conscience, but they have recently discussed a cheap solar concentrator, peanut sheller, a low cost water purification, and they host the International Development Design Summit and IDEAS.
No, this is nothing ground-breaking technology wise, but they are cleverly using inexpensive technology to provide capability to a wider range of people. And that's a good thing. -
Re:iLinkIt
Remember the Sokal Affair, where a physicist submitted a nonsense article to a humanities journal to see whether there was any substance to the field? His paper was accepted, and there wasn't. I wonder how susceptible Slashdot would be to the same kind of made-up nonsense.
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Use Cilk
Just looked at libdispatch source code. It is apparently very Mac OS X specific, and will take a lot of work to be ported cross platform. The queue implementation also looks like it imposes a lot of overhead, so it is not very useful for parallelizing short-running "blocks" of code.
Why not use something like Cilk which has proven its salt? The only caveat of Cilk is that it requires any parallel code to be compiled with the Cilk compiler (which will generate C code), and unless you're willing to kickstart the Cilk runtime manually, any caller of the parallel code needs to be compiled with Cilk too, which includes main(). The technical reason is Cilk does a continuation passing style transformation (requiring a different calling convention) which allows a function caller to be stolen by the work-stealing scheduler while the function waits for the callee to finish, allowing the critical path to focus on work instead of manipulating the task queue. The result is a highly efficient and scalable parallel execution runtime, the best I've seen.
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MIT does
In fact, our public clusters run a customized version of Ubuntu called Debathena: http://debathena.mit.edu/
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MIT does it for free
How could you possibly evaluate the accreditation of a scheme like this? Who grades the work? Computers can't grade essay questions, and multiple choice isn't sufficient to evaluate college level work. Where's the exposure to other students you normally wouldn't interact with? College is a process of intellectual ripening and social coming of age; a computer can't substitute for a brick building, unless you are already past your formative years. Will there be enough revenue to compensate the person who puts the lesson plans together (you know, the one with the earned Ph.D).
Or just skip all this crap and get a free MIT education http://ocw.mit.edu/OcwWeb/web/home/home/index.htm .
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Re:Does it really matter?
Some of the maths behind `coded apertures` seems a little advanced, for me at least. It's cool though. The wikipedia article on it is rubbish - instead check out these:
http://groups.csail.mit.edu/graphics/CodedAperture/
http://astrophysics.gsfc.nasa.gov/cai/ -
Is His Hubris Humerous? Hardly.
All together, the evidence for magnetic monopoles "is now overwhelming", says Steve Bramwell, a materials scientist at University College London and author on one of the Science papers and one of the arXiv papers.
...Even without directly seeing one, Bramwell says that he is certain that the monopoles are there. "I don't think anybody could question it after this flurry of papers," he says.
This mentality is a good example of what Joel Spolsky calls fire and motion. You just keep moving, keep publishing, keep innovating, and your opponent is so busy trying to catch up or deal with your earlier work that you gain huge momentum. Sometimes unstoppable momentum. People just can't deal with the information overload.
When the crystals are chilled to near absolute zero, they seem to fill with tiny single points of north and south. The points are less than a nanometre apart, and cannot be measured directly. Nevertheless, Morris and other physicists believe they are there.
For 30 years, physicists have believed that the universe is made up of tiny vibrating dimensional strings which only they are clever enough to understand. A fine idea, except it turns out not even they are clever enough after all. Nevertheless, they persist in this belief because the mathematics is beautiful. Likewise, many physicists persist in their belief in magnetic monopoles because the concept is beautiful, or some other such rubbish. Look! It even makes Maxwell's equations symmetric. So what? What's so important about having symmetric equations. Unsymmetrical ones are so much more interesting!
There's only one arbiter in physics, and science in general. It isn't a "flurry of papers". It isn't "beauty" or "symmetry" or "elegance" or "coolness". It isn't how many people agree with your viewpoint. It isn't how many journalists you can get to print words like "overwhealming evidence" in headlines. It isn't how much "supporting (online) material" you can find to back you.
The one, only, and final arbiter is the experiment. An honest to gods experiment. It finds things. It separates truth from fiction. You can try to twist the meaning of the result this way and that, throw back the grenade and carry on with your fire and motion, but in the end the results of all those experiments will finally weigh down your dishonesty and halt your advance.
There are no magnetic monopoles. You can try to separate north and south pole. You can even construct models of "magnetic charge" and dipoles if you like. But in the end, you can't get a north pole without having a corresponding south pole, very, very close by.
Modern science, and worst of all physics, is in a deplorable state. Cargo cult scientists,frauds, charlatans, fakes, and deluded true believers(Yes I'm serious about that last link) have saturated certainly the media circuit, but I fear many physics departments as well. Sensationalism and media attention are now as never before, deciding what the "consensus"* in science should be. It's disheartening to see the world lose its faith in the method of observation, hypothesis, experiment and above all skepticism that has served it so well for so many centuries.
P.S.
*Before the cranks jump in; No, I do not in fact, doubt the reality of anthropogenic climate change. -
Re:Two reasons
You've clearly never been to a DIY fantasy-land like Maker Faire. In many ways, electronics are becoming easier to hack together, because higher-level components and circuits are available for integration into something more powerful than one could do from the old electronics magazines (look at what FPGAs did). Instead of Legos, now kids can build their own robots. Instead of the simple Logo programming language (which I grew up on), kids now have: Scratch. It allows them to create whole games with just about the same learning curve as Logo. I will concede that patents are becoming a bit absurd.
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Re:a few different things going on
Well, descriptively speaking, there's a lot of argument, as papers participating in the argument continue to be published. =] The hottest topic at the moment, afaict, is a dispute being a statistical view of boosting and opponents of the statistical view. There's a good back-and-forth on that in "Evidence contrary to the statistical view of boosting" (JMLR, 2008) and the 6 replies (and rejoinder to the replies) that were published alongside it.
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Re:Some PerspectiveThat is a pretty accurate description, especially
Our educational system itself is a joke.
If you were painting or washing cars (the euphemism I use for outsourced IT work) and some guy in a poor country across the world offers to do the same for half or even quarter the rate, capitalism cannot afford to employ you. Americans have two options - either whine yourself into irrelevance or pull yourself by your bootstraps, retrain and do things higher up on the value scale like designing new cars or even inventing new automobile technology. American universities like MIT are already working towards this and moving to newer paradigms in engineering education. Take a look at Geeks and Chiefs: Engineering Education at MIT.
And yes, not everyone in India wants to paint cars forever. They are very eager to design and invent new stuff too. Americans have had a head start and now a good opportunity. History will record whether they were smart enough to capitalise it. -
Re:Seeing Sound?
An iPhone or PDA easily has enough computing power to do a real-time spectrogram, but to be nitpicky, it's a time-frequency plot, not just a frequency plot. In my experience it's pretty hard to pick up the ability to read spectrograms of speech accurately and quickly, then again it's not my only access to speech. At the very least it would increase a deaf user's awareness of sound in his or her environment, and there would be at least a minimum level of discrimination between various types of sounds.
As for alternate modes of sensation (assuming something like a cochlear implant is a no-go), look into some of the work being done in vibro-tactile devices - http://techtv.mit.edu/genres/18-education/videos/3557-speakers-and-signers-ted-moallem-sensible-technologies----sensory-communication-aids-for-the-developing-world -
Re:Theora
With any luck, the findings pointed to by http://web.mit.edu/xiphmont/Public/theora/demo8.html may lead to better quality/bit-rate ratios in the future.
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Theora 1.1
Monty from Xiph has provided an update on the state of the upcoming 1.1 release. It makes for interesting reading.
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Two good examples (and classic)
Have you looked at Wikipedia?
You can try some ideas from books already available in print as well as in electronic versions.
SICP
Stony Brook Algorithm Repository -
Re:Gutless?
So it's diesel - is it as gutless as I've been led to believe diesel cars are? I've never driven one, but I am genuinely curious....
No, its a hybrid. take a look at the very simplified electric motor torque curve at
http://lancet.mit.edu/motors/motors3.html#tscurve
Not exactly gutless when accelerating.
As an anecdotal data point, my wife's prius is easily the fastest 0-20 car I've ever been in. Performance drops off above that point, and it requires new tires on clean fresh dry pavement.
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Heh
For those who don't get the parent's joke Logo is often considered to be derived from LISP.
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Re:Programming practice
As a former participant at such contests, here are some sites that helped me along the way:
- Study Introduction to Algorithms, now at third edition: http://mitpress.mit.edu/catalog/item/default.asp?ttype=2&tid=11866 (This is one of the best books in the field and one I personally read, that's why I'm recommending it. There are of course other books that I don't know of.)
- Check out courses for computer science from different universities: http://academicearth.org/
- USACO has a training path witch gives you problems to solve and increase in difficulty as you go along
- Competition sites like topcoder.com also have educational content beside the weekly algorithmic contests: http://www.topcoder.com/tc?module=Static&d1=tutorials&d2=alg_indexAnd most importantly, solve lots and lots of problems. Beside USACO and topcoder, here are some ACM like online judges:
- http://uva.onlinejudge.org/ (some are easy, others are easy if you get the idea and some of the last ones are hard)
- http://www.spoj.pl/ (most are hard!)Bonus: If you're romanian, you should really check http://infoarena.ro/ It's the biggest online community in computer science with articles, problems, helpful guys.
Hope this helps!
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Cool
This is very cool stuff. But in terms of adapting 'remarkably quickly' to visual stimuli after congenital blindness, I'm slightly dubious. There's been quite a bit of recent research done on this recently through Project Prakash (which is also a very cool humanitarian mission at the same time), which finds that adults who regain vision see things very differently than we do... For example that have major problems with depth, object segmentation (think two overlapping squares -- normal observers will typically say there are two squares, overlapping, while newly seeing adults will report 1 square, where the overlap occurs), full field motion etc.
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If you make it to Nebraska
While I very much enjoyed the MIT museum http://web.mit.edu/museum/ while hunnymooning in Boston, we live in Nebraska, and I can recommend a few places here... Pioneer Village in Minden http://www.pioneervillage.org/ Stuhr Museum in Grand Island http://www.stuhrmuseum.org/ Of course there is the S.A.C. museum near Omaha http://www.strategicairandspace.com/ Elephant hall in Lincoln http://www-museum.unl.edu/ And the Omaha Zoo http://www.omahazoo.com/ There is also a local history Museum in Gohner, http://www.sewardcountymuseum.org/home.html which has a miniture live steam train that you can ride on weekends http://www.the-chippewa.org/index_content.html
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Re:Please tell me...
That's a pretty absolute assertion you're making. Do you really believe that software patents are the only way knowledge of software inventions gets transferred/created in our society?
That's not what I asserted. I asserted that if an algorithm is kept a trade secret and the source code closed then the public will never find out about it (barring, of course, illegal disclosure of the trade secret or independent discovery by another party that then discloses it).
And of course software patents are not the only way knowledge of software inventions gets transferred. Open source and academic publications are two other routes. The problem with the former is that open source is not particularly innovative. A study of 500 mature, actively developed open source projects that only 1% of them contained a new technology and addressed a new market or new user need. Open source is good at providing good, cheap software, but it is not particularly good at innovating.
Academic publication is all well and good, but ultimately someone has to pay for labs and salaries. Software patents step in as a way for academic discoveries to be commercialized. For example, some of the fundamental patents underlying Google are owned by Stanford, which is where Page and Brin invented PageRank and other related technologies. Google pays Stanford a non-trivial royalty for the exclusive license to those patents. Thus, the patents on successfully commercialized technology fund more academic research.
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Re:Please tell me...
This presumes that the crass entrepeneur is the driver of innovation in software.
The PageRank algorithm on which the Google empire rests was invented by Larry Page and Sergei Brin. They published the algorithm, patented it, and went on to become incredibly successful 'crass entrepreneurs.' Google owns dozens of software patents on key technologies such as its Map-Reduce implementation and AdWords. Few would say that Google is not a driver of innovation in software.
Usually it's the exact opposite sort of person that drives software or scientific innovation.
That's a fairly strong claim. Would you care to provide evidence that innovators are not motivated by financial reward, which is typically either received directly through their own crass entrepreneurship or indirectly through the commercialization of their innovations by others?
Who, in your view, is driving innovation in software? It's not open source: A study of 500 mature, actively-developed open source projects found that only 1% of them included a new technology and addressed a new market or user need.
Necessity is the mother of invention, not greed.
Then why have a patent system at all?
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Re:Voting needs to be transparent
This article by Chaum is the one I always point to when people ask for a less technical explanation:
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Rivest to the rescue?
The article is interesting, but Schneier is not the first person to consider such questions. Last year (I think?), Ron Rivest gave a couple talks at my school on the subject of voting. One of them was about auditing, and the other was about using crypto to achieve safer e-voting. You can see something similar to what he said here: http://people.csail.mit.edu/rivest/RivestSmith-ThreeVotingProtocolsThreeBallotVAVAndTwin.pdf Some of the comments here have been arguing over the relative merits of verifiability and secrecy (as in having voting receipts or whatever). Cryptographic methods can be used to partly reconcile those ostensibly contradictory goals. Anyhows, have fun reading.
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Re:Voting needs to be transparent
If you can confirm your vote, you can prove how you voter to others. This makes room for buying and extorting votes! I can imagine some employers requiring you to prove you voted correctly to keep your job.
Or union bosses. Or the local political-organizing group slipping you some money in exchange for voting a certain way. Or even an unorganized gang of thugs trying to intimidate you (think a group of rednecks who suspect you might have voted Democratic, or a group of Berkeley hippies who suspect you might have voted for Prop 8).
But I disagree with your first sentence. It's certainly true about the scheme proposed by GP, but contrary to intuition, there are ways to confirm your vote without being able to prove how you voted to others.
Such voting systems typically use a "cut-and-choose" method in which your vote is split into two or more pieces, any one of which is useless for determining how someone voted, yet together create the full vote. The voter takes a copy of one of the pieces as a receipt and can verify that the piece was counted correctly. So if there are two pieces overall, someone trying to tamper with the votes would have a 50% chance of being caught for each vote tampered with, which quickly becomes negligible for any significant number of votes. Yet the voter can show the piece to others, and it doesn't give any information about how they voted.
Here (PDF) is one method for doing this, by David Chaum.
Here (PDF) is another (without cryptography!), by Ron Rivest.The issues with these new systems seem to be usability, inertia, and public trust. Usability: Voting should be extremely simple for the voter. If Great-Grandma can't do it, it's not going to be our voting system.
Inertia: Current election systems seem to be "good enough" for most people; despite some agitated geeks and the occasional news story about voting machines being laughably insecure, there isn't a huge popular movement to change. (Cost of switching systems can also be included here.)
Public trust: Even if cryptographers agree that a system is secure, if the system involves a user experience any different from the familiar "check off from a list of names" protocol, they'll have to work to convince the lay public that it's ok. -
Quick answer and research links
Quick answer:
Introduction to Information & Communication Technology - Using Free Software and Open Technologies
Edited By: Will Brady
http://openbookproject.net/courses/intro2ict/index.xhtmlThe Non-nerds Guide to Computers
http://en.wikibooks.org/wiki/Non-nerds_Guide_to_ComputersBut seriously spend half an hour going through results of Google search on these terms: open textbooks computing
You will have to go through the texts yourself but there are many out there at many different levels.
Here are the main resources.
Wikibooks
http://en.wikibooks.org/wiki/Subject:Computing
http://en.wikibooks.org/wiki/Non-nerds_Guide_to_Computers
http://en.wikibooks.org/wiki/Computers_for_BeginnersFlat World Knowledge
http://www.flatworldknowledge.com/MIT Open Courseware
http://en.wikipedia.org/wiki/MIT_OpenCourseWare
http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/index.htmMake Textbooks Affordable open textbooks
http://www.maketextbooksaffordable.org/statement.asp?id2=37833Student PIRGs
http://www.studentpirgs.org/open-textbooks-catalog#computersciList at Walla Walla Community College
http://www.wwcc.edu/CMS/index.php?id=2835The Assayer free books list
http://theassayer.org/
http://www.theassayer.org/cgi-bin/asbrowsesubject.cgi?class=Q#freeclassQAcCalifornia Learning Resource Network (only math and science)
http://clrn.org/FDTI/index.cfmOER Consortium
http://oerconsortium.org/discipline-specific/#ComputerOpen Book Project
http://openbookproject.net/
http://www.openbookproject.net/courses/Introduction to Information & Communication Technology - Using Free Software and Open Technologies
Edited By: Will Brady
http://openbookproject.net/courses/intro2ict/index.xhtmlO'Reilly Open Books
http://oreilly.com/openbook/Textbook Revolution
http://www.textbookrevolution.org/index.php/Book:Lists/Subjects/Computer_Sciencehttp://www.opentextbook.org/
http://freelearning.bccampus.ca/openTextbook.php?page_id=221&bookmark=Computing -
Re:You could always write one...
Here's your whole job done already:
MIT OpenCourseWare - Intro to Computer ScienceWow. That's the first OCW link I've seen where click Syllabus doesn't take you to an expensive-as-hell textbook you need to follow the material. I'm impressed.
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Re:MIT OpenCourseWare
+1.
I actually used these at the same time as taking the lower level equivalent courses locally, 2000 miles away. I was out of school for 10 years prior and worked full time while in school full time. When study time finally came around, I couldn't always make sense of the notes I took in class. When I fired up the lectures on the same topics from http://ocw.mit.edu/OcwWeb/web/home/home/index.htm , I could effectively pause, and repeat segments of lectures until I fully grasped the concepts and ideas, then proceed at my own pace.
When I saw this topic, I knew I had to post about it.
TLDR: E;FB
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MIT OpenCourseWare
Take a browse though http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/index.htm There doesn't seem to be an 'overview' class like the one you're describing, but perhaps you could combine some of the introductions of the various courses.
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Re:You could always write one...
Here's your whole job done already:
MIT OpenCourseWare - Intro to Computer Science
If you need some more advanced concepts:
Full Course listNow how can I get a cake college teaching job where someone who is supposed to know all about information systems can't find stuff like this in the two seconds with google it took me? I suppose they just don't pay enough for employees...
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Re:You could always write one...
Here's your whole job done already:
MIT OpenCourseWare - Intro to Computer Science
If you need some more advanced concepts:
Full Course listNow how can I get a cake college teaching job where someone who is supposed to know all about information systems can't find stuff like this in the two seconds with google it took me? I suppose they just don't pay enough for employees...
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Re:First Post
You fight disease with the spleen you have. Not the spleen you want.
Or if you prefer something more highbrow, All The Bard's Spleens.
For fun, be sure to check out the alt.spleen FAQ.
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Re:40%?
Thanks for the link, it's a great article. It does seem to show however, that the 'move over' camp is in the majority even though a few states rule the other way, as does this compilation of rules linked in the article: http://www.mit.edu/~jfc/right.html. Based on the color code of that list, I'm guessing the guy who made it thinks driving the speed limit in the left lane is a bad idea. I tend to agree, but my OCD side really dislikes the idea of having to move over to allow somebody else to break the law. Therefore, I sort of like the 'you can do the speed limit in the left lane' idea, but only as a way to pressure governments to raise the speed limit. Unfortunately, it really doesn't work that way.
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Re:Californians and their "log jams"
(a) Notwithstanding the prima facie speed limits, any vehicle proceeding upon a highway at a speed less than the normal speed of traffic moving in the same direction at such time shall be driven in the right-hand lane for traffic or as close as practicable to the right-hand edge or curb, except when overtaking and passing another vehicle proceeding in the same direction or when preparing for a left turn at an intersection or into a private road or driveway.
(b) If a vehicle is being driven at a speed less than the normal speed of traffic moving in the same direction at such time, and is not being driven in the right-hand lane for traffic or as close as practicable to the right-hand edge or curb, it shall constitute prima facie evidence that the driver is operating the vehicle in violation of subdivision (a) of this section.
This is a pretty typical law - I know that PA has pretty much the same code. Doing a little quick research, State "keep right" laws - you can see that most states (31/50) have the exact same laws. Six states (IL,KS,KY,ME,MA,NJ) actually forbid use of the left lane, and two states (PA, WA) have a slight ban on the using the left. The rest of the states have no specific law, though all of these states require you not to obstruct the flow of traffic.
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Re:This is a great breakthrough...
He's right; researchers at MIT confirmed that aluminum foil actually amplifies, rather than blocks, the government's mind control rays.
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Re:take a look at alice.orgI'll have to respectfully disagree there. Having TA-ed a programming class that used Alice and Python, my experience is that students find 3D a distraction: they spend too much time tweaking their objects' positioning and not enough on actually writing code.
Plus, Alice's lack of physics modeling makes it rather unintuitive to use at times. I'd rather recommend MIT Scratch -- it's 2D, object-oriented, with a visual drag-and-drop approach that makes it really hard to make syntax errors.
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Re:Pascal
A beginning programmer should stay away from threads. In fact, most programmers, beginning and old, should stay away from threads.
I couldn't disagree more. Multi-threaded and multi-processor programming is only going to be more common in the future, not less. I'll admit that trying to debug multiple threrads in a traditional programming environment is something that is difficult to nearly impossible (in some cases) to do, but you don't have to be living in abject fear of the topic.
IMHO one of the best introductory environments for programming is Scratch, developed by the MIT Media lab. While it is geared more for kids rather than adults, developing software in that programming language uses multiple threads as if it was the very air that you breathe. Except for all but the most simple examples, code written in that language simply must use multiple threads in order to work. And yes, I've seen 8 year olds be successful in writing what would be in most other programming languages a nightmare from hell itself with hardly even a second thought.
That really is the issue: The thread behavior of a language, if it is to be done right, needs to be something inherent in the language itself and not something tacked onto it ad-hoc after the fact. Most software developers working with threads use operating system calls and tend to work at it on too low of a level to make it work properly without some significant headaches.
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scratch
http://scratch.mit.edu designed explicitly for this
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Re:Its the waste stupid.
I think this is what you are referring to: http://techtv.mit.edu/videos/2843-recycling-span-classhighlightnuclearspan-waste-addressing-span-classhighlightnuclearspan-waste-in-the-21st-century
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Re:Poor guy...
Everyone dies. What is so wrong with going out at your own choosing?
Sounds like you've been reading Shakespeare. http://shakespeare.mit.edu/julius_caesar/full.html
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Re:59 Sq Miles for 1500 MW. Nuke Plant Better.
but do you have any figures linked to a real plant that can actually be named so that people know you are not pulling a fast one?
Sheesh, I already said - there are a bunch of them IN THE MIT STUDY. Here, the document under "update on the cost of nuclear power". Page 45. Table 3A & 3B, "Overnight Costs for Actual Builds". There are 11. This is the BASIS for the MIT estimates. E.g. there is Shika #2, an ABWR completed in 2006 at total project cost of 370 billion Yen = $3.9 billion US at current exchange rates. With PPP adjustment it came out to $2,280/kW.
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Re:59 Sq Miles for 1500 MW. Nuke Plant Better.Sigh.
1. Don't reference Other Countries nuclear programs. This is the United States,
My $4/W figure was the estimate for new United States reactors, according to the interdisciplinary MIT study The Future of Nuclear Power (the 2009 update).
Referring again to the MIT study, they explain in detail what goes into their cost models (the 2003 full report, appendix 5). It encompasses EVERYTHING - the entire plant (steam turbines and all), the operating costs over 40 years of operation, 40 years' worth of fuel, the decomissioning costs after those 40 years, the waste disposal cost under the current 0.1 c/kWh DoE fee, etc. The TOTAL cash flow is estimated at $4.5 billion (nominal) during the construction phase - see the supplemental paper Update on the Cost of Nuclear Power, table 6A (this doesn't include the financing costs - go down to 6C).
Of course, what's really interesting is the levelized lifetime cost, per kWh. The MIT study estimates this at 8.4 c/kWhe; I've surveyed a dozen other such levelized cost studies on my blog. Feel free to follow the links and read up on them.
By the way, the NRC fees a very tiny part of costs - currently $4.6 M/year, out of of the MIT estimate of $56 M/year of fixed O&M costs (for a 1 GW plant).6. Definitely not an engineer. Megawatts are always comparable, they are absolute quantities. A MW produced by a wind farm is the same MW produced by a nuke.
Nameplate capacities are incomparable. They represent peak power generation; but some power plants always operate at full power, and others operate intermittently, hence the energy yields (integral of power * dt) are completely different.
Yes, while wind provides a smaller percentage of it's capacity factor when compared to nuclear, that can be (supposedly) be defeated with large numbers of geographically dispersed wind farms.
No, that's a fallacy. 1 MWe of wind (nameplate capacity), at 30% capacity factor, averages 300 kWe (averaged over long time periods), with an instantaneous range of 0-1000 kWe. Adding together a thousand such (identical, independent) turbines gives you an average of 300 MWe, albeit with lower statistical variance - smaller fluctuations.
You are conflating two separate issues. One, is that the average output of a windfarm is a fraction of its nameplate capacity. Two, is that the output over time has very large variations. See? They are separate problems. -
Re:59 Sq Miles for 1500 MW. Nuke Plant Better.Sigh.
1. Don't reference Other Countries nuclear programs. This is the United States,
My $4/W figure was the estimate for new United States reactors, according to the interdisciplinary MIT study The Future of Nuclear Power (the 2009 update).
Referring again to the MIT study, they explain in detail what goes into their cost models (the 2003 full report, appendix 5). It encompasses EVERYTHING - the entire plant (steam turbines and all), the operating costs over 40 years of operation, 40 years' worth of fuel, the decomissioning costs after those 40 years, the waste disposal cost under the current 0.1 c/kWh DoE fee, etc. The TOTAL cash flow is estimated at $4.5 billion (nominal) during the construction phase - see the supplemental paper Update on the Cost of Nuclear Power, table 6A (this doesn't include the financing costs - go down to 6C).
Of course, what's really interesting is the levelized lifetime cost, per kWh. The MIT study estimates this at 8.4 c/kWhe; I've surveyed a dozen other such levelized cost studies on my blog. Feel free to follow the links and read up on them.
By the way, the NRC fees a very tiny part of costs - currently $4.6 M/year, out of of the MIT estimate of $56 M/year of fixed O&M costs (for a 1 GW plant).6. Definitely not an engineer. Megawatts are always comparable, they are absolute quantities. A MW produced by a wind farm is the same MW produced by a nuke.
Nameplate capacities are incomparable. They represent peak power generation; but some power plants always operate at full power, and others operate intermittently, hence the energy yields (integral of power * dt) are completely different.
Yes, while wind provides a smaller percentage of it's capacity factor when compared to nuclear, that can be (supposedly) be defeated with large numbers of geographically dispersed wind farms.
No, that's a fallacy. 1 MWe of wind (nameplate capacity), at 30% capacity factor, averages 300 kWe (averaged over long time periods), with an instantaneous range of 0-1000 kWe. Adding together a thousand such (identical, independent) turbines gives you an average of 300 MWe, albeit with lower statistical variance - smaller fluctuations.
You are conflating two separate issues. One, is that the average output of a windfarm is a fraction of its nameplate capacity. Two, is that the output over time has very large variations. See? They are separate problems. -
Re:59 Sq Miles for 1500 MW. Nuke Plant Better.
Nuclear power plants in the 1500 Megawatt range cost 30-40 Billion dollars just to build.
Nonsense. The new French reactor, 1650 MWe, has a pricetag of $4.8 billion. Recent Japanese and Korean reactors were in the same range - $2-3/W (PPP), as surveyed by MIT CEEPR (under "update on the cost of nuclear power"). The accompanying study (2009) predicts costs for new US reactors to be $4/W. In short, the numbers are consistent. You can look up cost figures, levelized cost studies (here's a start) up and down, and you will find this is true.
Wind Farms in the 1500 Megawatt range cost 300-400 million dollars to build.
Also nonsense. Just take one recent UK wind farm, which came in at £111 M for 60 MWe - $2.07/W, or extrapolating, over $3 billion for 1500 MW. You can survey costs all over the web, and this is typical. Whitelee, Europe's largest onshore farm, cost £300M ($496M) for 322 MWe, $1.54/W. Lynn and Inner Dowsing - UK's largest offshore farm - came in at £300 M ($496 M) for 194 MWe, $2.56/MW. The famous London Array is now at £3B ($4.96 billion) for 1,000 MWe: $4.96/W. (To be fair though, this represents a 200% cost overrun over the original estimates.) (Sorry about the angstrom signs: they are supposed to be British "pound" symbols)
Also, besides the fact that your bogus figures for wind are 10 times cheaper than reality (and for nuclear, 10 times more expensive than reality), your comparison is bogus in yet another away. You comparable incomparable quantities: a megawatt of baseload yields far more energy than a megawatt of wind power - because it yields power continuously, whereas the wind turbines are very frequently down, or generating at fractional capacity. This is represented by the "capacity factor", which is the fraction of the nameplate capacity actually achieved by a power plant - ratio of [average power output]/[power capacity]. And while nuclear power plants, as generally reliable baseload plants, run at 90%+ capacity factor - that is, average 0.90 MWe of generation for each 1 MWe of nameplate capacity - wind farms, becuase of the obvious intermittency of wind, average only 20-30% capacity factors, with some exceptional offshore locations yielding 40%. Those megawatts are completely incomparable: 1 MWe of nuclear yields 2-4 times more energy than 1 MWe of wind power. -
Re:59 Sq Miles for 1500 MW. Nuke Plant Better.
Nuclear power plants in the 1500 Megawatt range cost 30-40 Billion dollars just to build.
Nonsense. The new French reactor, 1650 MWe, has a pricetag of $4.8 billion. Recent Japanese and Korean reactors were in the same range - $2-3/W (PPP), as surveyed by MIT CEEPR (under "update on the cost of nuclear power"). The accompanying study (2009) predicts costs for new US reactors to be $4/W. In short, the numbers are consistent. You can look up cost figures, levelized cost studies (here's a start) up and down, and you will find this is true.
Wind Farms in the 1500 Megawatt range cost 300-400 million dollars to build.
Also nonsense. Just take one recent UK wind farm, which came in at £111 M for 60 MWe - $2.07/W, or extrapolating, over $3 billion for 1500 MW. You can survey costs all over the web, and this is typical. Whitelee, Europe's largest onshore farm, cost £300M ($496M) for 322 MWe, $1.54/W. Lynn and Inner Dowsing - UK's largest offshore farm - came in at £300 M ($496 M) for 194 MWe, $2.56/MW. The famous London Array is now at £3B ($4.96 billion) for 1,000 MWe: $4.96/W. (To be fair though, this represents a 200% cost overrun over the original estimates.) (Sorry about the angstrom signs: they are supposed to be British "pound" symbols)
Also, besides the fact that your bogus figures for wind are 10 times cheaper than reality (and for nuclear, 10 times more expensive than reality), your comparison is bogus in yet another away. You comparable incomparable quantities: a megawatt of baseload yields far more energy than a megawatt of wind power - because it yields power continuously, whereas the wind turbines are very frequently down, or generating at fractional capacity. This is represented by the "capacity factor", which is the fraction of the nameplate capacity actually achieved by a power plant - ratio of [average power output]/[power capacity]. And while nuclear power plants, as generally reliable baseload plants, run at 90%+ capacity factor - that is, average 0.90 MWe of generation for each 1 MWe of nameplate capacity - wind farms, becuase of the obvious intermittency of wind, average only 20-30% capacity factors, with some exceptional offshore locations yielding 40%. Those megawatts are completely incomparable: 1 MWe of nuclear yields 2-4 times more energy than 1 MWe of wind power.