Domain: umich.edu
Stories and comments across the archive that link to umich.edu.
Comments · 1,427
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Re:Just because you can't see it...How confident are the makers of stegdetect that no steganographic images would slip past their program? Does their program simply work for all known steg. algorithms, or would it detect some or all kinds of new algorithms?
Stegdetect checks for the signatures of three steg programs (JSteg, JPHide, and OutGuess
.13b)(Research Paper), and it does not detect new algorithms. Also, the effectiveness of stegdetect is determined by what steg program was used. It missed from 5% of JSteg stegs to 60% of OutGuess stegs. Finally, they did not try to detect stegs generated with OutGuess 0.2 because it has a better method of randomly selecting bits to change. -
The point of Stego is that you can't see it.For those who prefer clicking to cut-and-pasting, the Steganography update is here.
I suspect there are several reasons why they haven't found any Stegonography in Usenet pictures:
- Very few people find it necessary to hide information in Usenet.
- Of those who might find it necessary, few actually have heard of Steganography and know how to use it.
- Those who know enough about Stego have encypted their messages first; you won't find these with dictionary attacks - the method the article suggests they used on "suspicious" images.
This Article seems to suggest that it isn't possible to hide info in gifs such that it is undetectable and that more research should be done on JPEGs. Anyone know the state of the art on this?
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Re:Uh-oh (was Re:Safety?)
According to this document, think like this was made doubleplus bad in 1996.
Or has everyone forgotten that one already?
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Re:Yes there is
Any decent admin worried about security will disable booting from CD (and floppy) and password-protect the BIOS configuration screen.
Except that you don't always have control of all of the workstations. University personally owned computers, for example. What you're suggesting will only work in a rigidly controlled environment. Better to have a more secure filesharing methodology. NFS4, for example. Or I understand AFS to be more secure. However, this would seem to be a difficult system to use in an evironment that must also cooperate with, say, Windows clients.
I hate to say it, but as things stand today, you'll end up with a much more secure shared filesystem if you use samba + windows clients. Unless you use a system like AFS that doesn't play nice with others. This is definitely a chink in the *nix armor.
Maybe I just don't understand AFS well enough. I've been pinning my hopes on NFSv4, but this certainly looks discouraging. Maybe umich will save us. By June 30th, they say... Here's to William, Jim, Kendrick, and Jake! -
Uplink 2wroot writes: "Well, it looks like the perfect convergence for the average Slashdot reader. What we've got here is a game that is approaching the Slashdot Enthusiast's Valhalla. It's released under Alpha, ARM, Intel x86, Motorola 680x0, PowerPC and SPARC, costs a mere 0 USDs, and has no middleman to jack prices up. Of course, that means it's not available in stores, nor will it be seen on TV, but according to Newsforge, it's got great gameplay. If you install it, you get 25 points. If you also get networking to work, you get another 25 points, sound - another 25. If you correctly configure X, you got yourself another 25 big ones. So, will 0 bucks, a fresh game idea, and a Linux challenge make others in the gaming world stand up and take notice?"
Wroot, the game master (score: 100)
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What about file sharing
I'm a linux bigot, for sure. But one hurdle that has to be overcome before anyone who's not insane sells this idea to their boss is the utter lack of secure filesharing for a multi-user office. Usernames and passwords, in plain text, in an automount config file is not an option. Experimental filesystems are not an option. NFS is not an option (got root on the client (install cd) you've got access to anything.). OpenAFS maybe, but not exactly a widely discussed or supported system.
NFS4 sounds like the ticket, but the two available open implementations (umich and samba team) are in their infancy.
Until this problem is solved, this whole discussion is moot, as far as I'm concerned. -
University of Michigan Smartcard Software, Info
The University of Michigan's CITI group does indeed have a bundle 'o info and programs available for applications of a Smartcard environment if you're interested.
Though I have to say I enjoy being able to login without one here at the moment, but maybe that's just me. -
The differences are minor...Hi,
The reality is that the differences are really minor, and, now that RSA is legal, openssh can be setup to act almost exactly the same as closedssh.
The only signicant difference between them for most peole is the price.
There used to be a fair bit of difference, but at least for unix, this is no longer true. Since 2.5 openssh has supported sftp. Since 3.0 it supports rekeying a session. With external PAM modules you can support smart cards and securid logins.
The one advantage that ssh has over openssh is that this is all integrated into one package. The smartcard support is built in, you don't have to go looking for support.
If you are not planning on using smartcards or tokens, then openssh wins based on price alone. You can get it pre-compiled for most platforms, so the compilation is not so much the issue. Otherwise you have to weigh the choices a little more carefully. Check to see if your required token/card is supported by both. If not, then it is likely to be easier to add support into openssh, having the source and all.
In terms of windows clients...that is one big differentiator. Again, mostly money! We use tera-term and that works quite well, but does not do ssh V2 protocols.
In either case, you are buying a big whack of security, but don't forget, passwords can be extremely weak! Don't let up on the other security policies just because you now have SSH. (And yes, I know that the poster is not responsible for this, this is just a general admonition
:-)Whatever you get, I wish you the best of luck.
Now for the gratuitous links:
:-) -
Sheer chutzpah
I've always been interested in computers (as have most of the
/. readership). I had to leave school for financial reasons, and needed to find a job and FAST. All the UNIX I knew I'd picked up on the job (I worked as a web developer for a time) as well as in my introductory EECS courses. I knew basic commands and plenty of programming (Perl), so I took the 'Linux plunge' in my own time to teach myself some things. Many hard knocks, late nights, huge fuck-ups, and O'Reilly books later, I am a full-time UNIX Systems Administrator, with crazy-mad Linux (Debian, baby!), Solaris (v.2.5 and up), IBM AIX (I don't want to talk about it), and HP-UX )God save us) skills. My web development background dovetailed nicely with my knowledge of Apache and Netscape (yes, they still make 'em) web servers.
That's kind of the abbreviated version. My resume page outlines the journey a lot better.
Luck! -
Sheer chutzpah
I've always been interested in computers (as have most of the
/. readership). I had to leave school for financial reasons, and needed to find a job and FAST. All the UNIX I knew I'd picked up on the job (I worked as a web developer for a time) as well as in my introductory EECS courses. I knew basic commands and plenty of programming (Perl), so I took the 'Linux plunge' in my own time to teach myself some things. Many hard knocks, late nights, huge fuck-ups, and O'Reilly books later, I am a full-time UNIX Systems Administrator, with crazy-mad Linux (Debian, baby!), Solaris (v.2.5 and up), IBM AIX (I don't want to talk about it), and HP-UX )God save us) skills. My web development background dovetailed nicely with my knowledge of Apache and Netscape (yes, they still make 'em) web servers.
That's kind of the abbreviated version. My resume page outlines the journey a lot better.
Luck! -
Sheer chutzpah
I've always been interested in computers (as have most of the
/. readership). I had to leave school for financial reasons, and needed to find a job and FAST. All the UNIX I knew I'd picked up on the job (I worked as a web developer for a time) as well as in my introductory EECS courses. I knew basic commands and plenty of programming (Perl), so I took the 'Linux plunge' in my own time to teach myself some things. Many hard knocks, late nights, huge fuck-ups, and O'Reilly books later, I am a full-time UNIX Systems Administrator, with crazy-mad Linux (Debian, baby!), Solaris (v.2.5 and up), IBM AIX (I don't want to talk about it), and HP-UX )God save us) skills. My web development background dovetailed nicely with my knowledge of Apache and Netscape (yes, they still make 'em) web servers.
That's kind of the abbreviated version. My resume page outlines the journey a lot better.
Luck! -
my Sci-fi recommendations
I like Guy Gavriel Kay very much... his Fionavar Tapestry trilogy is very well done. It's one of the few trilogies that I caught as it was being written so I had to wait impatiently for the next book to come out.
:)
Another must-read author (if you ask me, that is) is Storm Constantine. I didn't care much for her book Sea Dragon Heir, but her Wraeththu trilogy is wonderful. If I could have only three books in my life, it would be these three. Eventually I'll have to order some more of her stuff... I can never seem to find it in bookstores.
If anyone's interested in some literary analysis of the SF/Fantasy genres, check out the Genre Evolution Project at the University of Michigan. It's still a work in progress (papers are being published as we speak), but interesting nonetheless. -
Noooooooooo!
Since I first got my hands on my 48GX back in '95, I've been a convert. RPN makes an incredibly elegant interface for rapid computation, and HP makes some sturdy, ergonomic hardware to boot. (Gotta love those clicky keys--much more "positive" than the mush that TI puts out.)
Just for the record, this is all your fault. Yes, you. You know who you are. You bought the TI-8x because it was cheap and everybody else had one. (Kinda like Win95, except for the cheap part.) I hope you're happy--next time I have to buy a calc, I will be forced to relearn algebraic entry. Of course, judging by the rate at which my HP48 is deteriorating/becoming obsolete, it may be 10 years before I need another calc.
I am doing my part to keep the culture of HP calcs alive. I wrote and maintain rpc, a curses-based RPN calculator which is very much in the spirit of the HP line. (Yes, this is a plug, but I thought it was appropriate...)
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Re:Please Read the Economist
While the greatest transgression that Nike has allegedly committed is not giving bathroom breaks,
If you think that's the "worst transgression" Nike's been accused of, you have another thing coming. -
The Wrong Problem
From a preservation perspective, the problem is not too little raw material, but too much. We are swimming in massive amounts of information with very little sense of which parts should be preserved over time.
Long-term preservation of digital materials is extremely resource-intensive, largely due to issues of hardware and software obsolescence. The problem is picking out the gems and keeping them accessible into the future, not needing to send more out-takes to the archives.
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AI
First, from Part II:
> Concept: The ability for artificially intelligent devices to feel emotions.
It's not at all obvious -- to me at least -- that we should want AIs to feel emotions. Who wants a warehouse full of smart bombs with hurt feelings?
Emotions can very clearly lead to inappropriate behavior. Granted, there may be times when emotions lead to positive behavior. But do they ever lead to positive behavior that couldn't be programmed into an AI without emotions? Unless that's the case then emotions are something known to be dangerous and not known to be useful, and therefore should be avoided as a life-threatening bug.
Granted, it may be a fact of nature that "intelligence" (whatever that is) is impossible without emotions. But unless/until that has been demonstrated, let's keep emotions off our wish list.
Now back to Part I:
> Concept: The idea of a computer becoming so complex it can understand, reason, listen, speak and interact in the same way as a human, including using deception and self-deception.
> Now we have: Machines that learn, software that breeds/replicates. 'Narrow AI,' i.e. computers that can perform 'narrow' tasks that previously could only be accomplished by human intelligence, such as playing games (e.g. chess) at master levels, diagnosing electrocardiograms and blood cell images, making financial investment decisions, landing jet planes, guiding cruise missiles, solving mathematical problems and so on. Currently exponential progress curve showing no sign of slowing down.
First, as with emotions, I dispute the desirability of AI agents that can knowingly deceive themselves and others.
Second, I'm not convinced that much of the laundry list in the second paragraph qualifies as "intelligence" instead of merely "appropriate algorithms". (Are we going to have to call MATLAB an intelligent agent because it's good at certain kinds of math problems?)
Third, I am amazed that they would say that we're making "exponential progress" in anything that might reasonably be called "AI". My games don't seem to ship with AIs that are "exponentially" smarter than the ones that shipped five years ago. Dish up some facts, please!
That said, here's a link to a paper [160K PDF] that someone turned me on to recently. It's from a talk some AI researchers gave at a conference last year. They start by asking where is all the cool movie-style AI, and answer with the observation that no one is working on it. Their proposal to remedy that situation is that AI researchers should get involved in game AI, because many modern games require agents that are more "intelligent" than the common solve-one-problem stuff that has been coming out of the AI community for the last few... decades.
I think the authors of that paper overstate their case by calling game AI agents "human level" AI, but at least it's a step in the right direction. It's a bit of a light-weight article, but it's an easy read. And it would be way nice if 2/3 of the world's academic AI researchers started working on gaming applications! -
Linux is not a contender...
Linux will not be deployed on corporate desktops until several things happen\.
Two commonly mentioned deficiencies are (1) overall functional immaturity (e\.g. - the spellchecking deficiencies the article mentions) and (2) incompatibil\ity with existing file formats. I.E. - the filter problem. These deficiences \are well known, and are being addressed, albeit not always as quickly as we wou\ld like.
However, there's another serious deterrant to corporate deployment of Linux \desktops that I never see mentioned: the complete lack of a sensible way of sha\ring centrally stored files. NFS (v2 or v3) is far too insecure to warrent ser\ious consideration for corporate desktops. Automounting SMB shares might work,\ if not for the necessity of storing authentication credentials in plain text c\onfiguration files. Again, unacceptable, both from a security and a management\ point of view.
Perhaps automounting could be improved. The other alternative is NFSv4, the\ specification of which mandates strong security. There are two free NFSv4 imp\lementations under development: a kernel level version at citi umich, and a user-level client/server b\eing developed by no less than the samba team. Both\ implementations are still quite immature, however.
Until Linux desktop users are able to easily and securely share files on a c\entral file server, it's difficult to envision widespread deployment in corpora\te environments.
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Re:Not a very good algorithm / implementation
Instead of me rehashing _why_ that implementation is such an infantile attempt at stego check out Outguess by Neils Provos a PhD student at the Univeristy of Michigan.
He also links to his own and other academic papers on the subject -
On a more serious note
Reminds me of all those fun hours wasted drawing cool pictures with LOGO.
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Let us read from the Koran
The Koran
"....Kill those who join other gods with Allah wherever you find them; besiege them, seize them, lay in wait for them with every kind of ambush...." (Sura 9:5)
"When you encounter the unbelievers, strike off their heads, until ye have made a great slaughter among them...." (Sura 47:4)
"....Make war upon such of those to whom the Scriptures have been given as believe not in Allah, or in the Last Day, and who forbid not what Allah and His Apostle have forbidden....until they pay tribute..." (Sura 9:29)
"Say to the infidels: If they desist, what is now past shall be forgiven them; but if they return, they have already before them the doom of the ancients! Fight then against them till strife be at an end, and the religion be all of it Allah's." (Sura 8:39)
"Proclaim a grievious penalty to those who reject faith." (Sura 9:3).
"I will instill terror into the hearts of the unbelievers: Smite ye above their necks and smite all their finger-tips off them." (Sura 8.12)
"Let not the unbelievers think they will ever get away... strike terror into the enemy of God and your enemy... rouse the faithful to arms!" (Sura 8:59)
Like Oprah said, what a beautiful religion. -
Let us read from the Koran
Koran
"....Kill those who join other gods with Allah wherever you find them; besiege them, seize them, lay in wait for them with every kind of ambush...." (Sura 9:5)
"When you encounter the unbelievers, strike off their heads, until ye have made a great slaughter among them...." (Sura 47:4)
"....Make war upon such of those to whom the Scriptures have been given as believe not in Allah, or in the Last Day, and who forbid not what Allah and His Apostle have forbidden....until they pay tribute..." (Sura 9:29)
"Say to the infidels: If they desist, what is now past shall be forgiven them; but if they return, they have already before them the doom of the ancients! Fight then against them till strife be at an end, and the religion be all of it Allah's." (Sura 8:39)
"Proclaim a grievious penalty to those who reject faith." (Sura 9:3).
"I will instill terror into the hearts of the unbelievers: Smite ye above their necks and smite all their finger-tips off them." (Sura 8.12)
"Let not the unbelievers think they will ever get away... strike terror into the enemy of God and your enemy... rouse the faithful to arms!" (Sura 8:59)
Oprah Winfrey was right. It's a beautiful non-violent religion. -
Re:Doesnt look that big right nowYes, there are camels in Afghanistan. The buggers are all over Asia minor.
The ties between Egyptians and Afghans of the Islamic Militant bent are quite strong, geographical differences aside.
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Re:Your sig reveals your ignorance
Have you read the Quran? Check Sura 2, versicle 191:
"And kill them wherever you find them. And expel them from the sacred places, because their presence is worse than the slaughter..."
First of all, your quote is wrong. Second of all, it's way out of context. You can read the whole thing here if you're interested.
In context:
[2.190] And fight in the way of Allah with those who fight with you, and do not exceed the limits, surely Allah does not love those who exceed the limits.
[2.191] And kill them wherever you find them, and drive them out from whence they drove you out, and persecution is severer than slaughter, and do not fight with them at the Sacred Mosque until they fight with you in it, but if they do fight you, then slay them; such is the recompense of the unbelievers.
[2.192] But if they desist, then surely Allah is Forgiving, Merciful.
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Re:Criminalization of EncryptionEncrypted messages can be easily hidden inside image and sound files (a process known as steganography). Its not a simple problem since there are an infinite number of encoding schemes which can be used. Such algorithms are only limited by the human mind.
Strangely enough I submitted an "Ask Slashdot" earlier this afternoon, on exactly this question: Just how good are steganography programs ?
A paper by Neils Provos and Peter Honeyman of U. Michigan mentioned in the Register today explains why it is very easy it is to spot steganographic content in JPEGs from two of the most widely used programs, JSteg and JPHide (even though they couldn't find any on EBay).
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Religious Consideration - Ultra-Conservativism
There is another more fundamental reason why a cashless society will not come to the States anytime soon. It has to do with the beliefs of many influential ultra-conservative religious groups.
These christian groups point to Revelation 13:16-18 as indicating that a cashless society is one of the "marks of the beast." These groups oppose a cashless society believing they are staving off the takeover of the Anti-Christ.
Google search with more info -
Another good lego movie:
Another funny lego movie is Legos are not Enough. I saw this at a film festival, and it beat out all the other 'serious' films, even though it was made by a bunch of engineering students whereas its competition was made by people who wore a lot of black clothing.
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Countries that sponsor terrorismIf you want an example of a country that sponsors terrorism, look no further than the USA. Try looking up the Irish Freedom Committee on Google, or read this article. Naive Americans have been funding terrorism in the UK for decades. Does that mean you need to bomb Chicago to rid the world of terrorism?
The CIA has assassinated a number of political leaders, including democratically elected presidents. Those actions would doubtlessly be called "terrorism" if the victims were Americans. Does that mean you need to bomb Washington to rid the world of terrorism?
The IRA has recently been training FARC terrorists in Columbia. The IRA is funded by American organisations like the IFC. Does that mean America is sponsoring terrorism in Columbia too? Wow, it's starting to look like one of those world wide terrorist networks I keep hearing about - and Americans are bankrolling it.
In reality, of course, it's not a global terror network. It's simply a bunch of violent, power-hungry organisations funded by naive individuals who are fooled by stirring words such as "patriotism", "history", "identity" and "freedom". I'm afraid your government is just another one of those organisations, and you are just another one of those fools.
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Not hard to find if you look
This is the first link I got after typing "Koran" into google:
http://www.hti.umich.edu/k/koran/ -
Re:verification please
I did a search in the Koran, and could not find the first sentence (the hour will come...), but I did find the second one (and kill them...).
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To make the world a better placeI maintain a fairly popular open source random number generator, Mersenne Twister. My reasons for producing and supporting open source software include:
- Payback for software I use
The best OS I've found to run simulations for my research is Linux. I'm indebted to the writers of the kernel, the GNU tools, gcc, plotutils, NEdit and much more. These were free to me monetarily, but writing software allows me to repay in kind. - Idealism of free (beer)
Software or information that costs $0.00 is infinitely better than that which costs $0.01. It can be copied, shared, and disbursed without hindrance. This openness leads to more users, which in turn promotes the development of better software. Free software is also far more useful. Consider how the growth of the US would be hampered if our interstates were privately owned toll roads rather than free-to-use public property. - Self expression
My job title is not computer scientist or network administrator, but computer programming is a valuable skill I possess. I write software as an outlet for my imagination and get pleasure from having my work appreciated by others. - Volunteerism
Many of us want to improve our society as a whole. I volunteer for Habitat for Humanity, the Detroit Project, and other charitable activities. Writing open source software is a way to help others escape from bad software and corporate greed.
- Payback for software I use
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Re:8290 + visor = net connection
There are alot of PalmOS applications that you will find on the net that will turn your palm/visor into a little workstation.
lftp- Ftp client for the palm.
Torpedo - html editor (use lftp to upload these pages)
mMail - the best pop3 email client for the palm
ptelnet - telnet client
PalmIRC - Palm irc client
TopGun ssh - ssh client
Palm httpd - httpd for palm
There is a large number of palm apps at http://palmgear.com if you are in search of some.
Visorcentral.com has alot of good info regarding handspring visors.
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Re:some smartcard infohttp://www.linuxnet.com/smartcard/software.html and http://www.citi.umich.edu/projects/smartcard/ have tons of free software.
nobody
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Wh
A cookie goes to whomever manages to implement this first!
:-D"
I don't have a cookie to give to him, but I'd like to grant an honorary cookie to Logic Bomb for correctly using who/whom :-). (I thought I'd never see the day when I'd come across "whom" on Slashdot)
PS Through researching the link for who/whom, I came across this surprisingly interesting discussion on teaching non-native English speakers the finer points of how to use the phrase "the hell!". -
Re:"2001"
who would read a story about a man who created a "monster" that was happy, friendly, and harmless, or a computer that worked perfectly and caused no trouble?
Actually, the scariest and likeliest tale about the future of AI, Jack Willamson's The Humanoids, fits your description exactly. The artificially intelligent robots in this novel are so helpful, so solicitous, and so efficient that they quickly reduce humanity to a state of enforced safe docility. This novel gives me chills just because it gets more plausible every day. -
Content Owner's strategy - divide and conquer
As time passes, it becomes more and more difficult to retain focus in addressing the Freedom of Speech and Privacy rights infringement of the DMCA, the WIPO treaties (which are an expansion of the Berne Convention Treaty) and now the potential for indevidual national legislation in each of the countries of the Free Trade Area of the Americas (FTAA). This newest development makes a consolidated stand against such over reaching legislation, substancially more difficult, and all but garentees the passage if DMCA-like legislation in countries other than the United States.
It looks like a strategy of divide and conquer will work for content providers in their quest to get this sort of legislation passed in countries throughout the world. The already fragmented opposition to this legislation stands to be further fragmented by the requirement that their efforts be divided accross (in the case of the FTAA) the countries of the Americas in order that there be no discrepency between countries' approaches to Intellectual Property.
I made this same argument with respect to the Open Source Community response to Craig Mundie and Microsoft with respect to the legitimacy of the GPL. There must be a focused response. The EFF has provided good leadership thus far, but in order to be an effective leader you must have followers. This is antithetical to the OSS mentality of independant developers (who seem to be the only ones focusing in this issue in any depth at the moment). This tendency, as evidenced by the response by some members of the community to the EFF request to discontinue protests in the Skylarov case durring negotiations with Adobe - where some members of the community basically told the EFF to stuff it and "You Can't Control Me". As a community, we need to realize that we need to follow leaders - not any leader, but those who have proven themselves - for our mutual benefit.
Additionally, I think it's worth spending a moment considering why the issues around the DMCA and similar legislation have recieved so little coverage in the popular media. I know it sounds paranoid, but since the deregulation of the communications industry, (we all know) conglomorates have been allowed to emerge which represent both the news media and content owners. I would not presume to make accusations that the popular news media has interests other than informing the public, but it's disappointing that we havnen't seen these issues addressed in the popular media. Their lack of coverage, leaves us with the responsibility of making others aware of Intellectual Property issues. IP is a complex subject, even explaining limited aspects of it in a comprehensive way is difficult, but we must begin focusing our efforts in this area as well.
--CTH -
HohohohHehe, here is the best bit from the above. Heh.
Difficult to find enough machines:- Started client on about 100 machines at University of Michigan without asking for persmission.
- Received a warning about losing my computer privilages the next day.
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stegdetect already does thisI am bit surprised. I released stegdetect in early February this year. It automatically detects steganographic content in images. It can even determine which program was used to embed hidden content.
You might also want to check the techreports that I published about my research.
At HAL 2001, I presented on Detecting Steganographic Content on the Internet. You might like that.
Dartmouth certainly seems to know how to do PR. I would just like to know where their publications are.
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stegdetect already does thisI am bit surprised. I released stegdetect in early February this year. It automatically detects steganographic content in images. It can even determine which program was used to embed hidden content.
You might also want to check the techreports that I published about my research.
At HAL 2001, I presented on Detecting Steganographic Content on the Internet. You might like that.
Dartmouth certainly seems to know how to do PR. I would just like to know where their publications are.
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Use this as an example
A lot of people have already written in with some good advice as far as FAQ's and the such. At the Univ. of Mich I think they do a very good job of handling this sorta thing with about 40,000 students. They have a whole entire division called ITD which may offer some material you may wish to cover.
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Use this as an example
A lot of people have already written in with some good advice as far as FAQ's and the such. At the Univ. of Mich I think they do a very good job of handling this sorta thing with about 40,000 students. They have a whole entire division called ITD which may offer some material you may wish to cover.
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What does E=mc^2 mean to you?
To me, it means:
Energy = mass * (speed of light) squared
This equation tells us how much energy we get from reactions that destroy mass, such as the radioactive decay of elements inside the Earth, or the nuclear fusion inside the Sun.
Now, if you want light in the past to travel, say, 6 billion (current) light years in the space of 6000 years, you need to speed it up one million times. In other words, you increase the amount of energy released by nuclear reactions by one trillion.
I'm not an astrophysicist, and the question "what would happen to the Sun if fusion released a trillion times as much energy" is a complicated one, but even if it didn't go nova I'd be surprised if Earth was still at a comfortable temperature.
I'm not a geophysicist either, but the question "what would happen to the Earth if radioactive elements released a trillion times as much energy" is a relatively (excuse the pun) easy one. Estimating the heat production of the Earth's core in this fashion at 4 * 10^13 watts, we can calculate the heat production of the early creationist Earth to be approximately 4 * 10^25 watts.
For comparison's sake, the Earth currently receives (1353 W/m^2) * pi * (6,360,000 m)^2 = approximately 1.7 * 10^17 watts from the Sun. So really, even if there was no Sun shining on Adam and Eve, they would still be getting about 230 times as much energy as we do today, raising the equilibrium temperature of the planet to a nice toasty 750 degrees Celsius. Maybe that explains Noah's flood, huh? All that water to cover the planet must have been in water vapor form before we cooled to under boiling temperatures.
Of course, if you want to explain just how *much* of those radioactive elements have decayed away in the multi-billion year old rocks we find lying around, you have to increase the rate of reaction (m, in the above equation) by another million fold. That brings our equilibrium temperature to about 5600 degrees Celsius... but wait, at that temperature all the rock is molten and radioactive decay products wouldn't get trapped next to their generating elements anyway.
I love creationist theories. My personal favorite are the wacky explanations of where all the water for Noah's flood came from ("vapor canopy"? anyone want to calculate the air pressure under something like that!?) and where it went.
For future reference, if you really think that Genesis is literal truth and God behaves like a parlor magician, then answers like "He created starlight already on it's way to Earth" and "he made ten million cubic miles of water teleport to deep space", however implausible sounding, are irrefutable. Once you try to explain miracles in terms of science, you're going to have to deal with its conclusions. -
Re:Free Dome? Expensive hair!
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I like the warning
New warnings for C code that may have undefined semantics because of violations of sequence point rules in the C standard (such as a = a++;, a[n] = b[n++]; and a[i++] = i;), included in -Wall.
I'm glad to hear that this warning has been added. I maintain an open source random number generator and the generation routine ran incorrectly when compiled with gcc-2.96. Fortunately a user ran the verification tests and figured out that my routines relied on a certain sequence of a[i++]=i evaluations. All the compilers that I had tested with used the same sequence, but the C standard leaves it implementation-dependent.
If a certain program raises these warnings, then it's best to know so it can be fixed. Otherwise it's likely to compile wrong on certain systems.
AlpineR
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tit-for-tat algorithm
If this is a 2+ player competition and they're the right sorts of games (like the rock-paper-scissors game that it mentioned), whoever wins it might have to figure out a way to consistently beat the tit-for-tat algorithm.
Tit-for-tat is one of the dead simplest game playing algorithms, and collectively it's one of the most successful.
It's based on the rule of "always do what the other player did last move". Under most circumstances it's impossible for it to actually win a game because the other player is always one step ahead. But its strength is in winning tournaments.
While it always loses, it never loses by much. This is different from other algorithms which usually have about as many weaknesses as they have strengths and will usually flunk out in at least some trials.
If someone can beat it consistently in a tournament situation, they really will have accomplished something in AI. Of course, this whole thing depends on exactly how the rules are structured, the scoring system and the information available to the program.
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auto-based peer-to-peer network
Another one bites the dust... Metricom is another ill-concieved, but well-intentioned idea that requires too much capital. I presented an idea for a peer-to-peer based network based on inexpensive networking devices installed in vehicles. (A MANET for those who know.) My thesis describes a compelling potential pathway for implementation of the network and argues that the network is feasible. You can read the abstract/full-text here: http://www-personal.umich.edu/~humbads/thesis/
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Re:Why? There are only 3 digits.
No, it was neither Texas nor Kansas (Kansas did do the 'evolution' thing, though).
There was, a year or so back, a hoax on the Internet about Alabama doing the same thing, but it was a hoax. The only factual evidence that anything of the sort ever happened was in Indiania, 1897, and it never even got close to passing: the Senators considered it to be a complete joke. -
UM Team
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UM Team
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The Nintendo R.O.B. problem and SpeakosFrom the story: Each one of the infrared beams represents one of the four buttons on a conventional Playstation joypad controller. Breaking a beam is the same as pressing a button.
As some of you may remember, the original NES came with two game pads, a light gun and a Robotic Operating Buddy (ROB) (Seen Here with the powerglove).
ROB was an interesting device, it had sensors which recieved signals from the screen, and it could move it's hands left or right and pick up or drop two gyroscopes. The gyroscopes could be dropped into a little motorized thing that spun them or they could be dropped onto two buttons. When playing a game that used ROB you'd put the second controller in a little holder on ROB that would translate those gyros that were dropped on the buttons into controller button presses.
So, during ROB enabled games, you'd hold the first controller, and issue commands to the game that would be translated into light signals that would be sent to ROB, who would pick up, turn, or drop gyros at your command. In the end it was a lot of work to simply push one of two buttons, and the ROB games inevitably sucked. Eventually, players would become so annoyed that they'd simply grab the second controller and push the buttons on their own, completely ignoring cute little ROB.
The moral? Well, making it a hassle to push one or two (or four) buttons doesn't a cool controller make.
Second, this thing is using a decent amount of technology to detect body movements, but it will inevitably make some mistakes. Think about the difference between typing and using speech recognition software... With typing, errors are your own fault, but they are often associated with the motor feedback associated with a miskey. With speech, you can say the word properly but the machine may misinterpret your speech. Unfortunately, this occurs un a probabilistic fashion, and is not easy to detect. Imagine if 1 percent of the time that you pressed a key on your keyboard it would be mapped to another key. It would be infuriating. Relying on a probabilistic detector is bound to lead to frustration.
Check out this PDF file for more on speech recognition errors.
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The closest approximation I can come up with...
and its seems to be _very_ close, is the sound the cicada's,
down south (southern US) make. A very load, very distinctive
buzzing.