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Other privileges of living in South Campus Commons include monthy inspections by the RAs (yes, you do pay money to a private company to live under Resident Life rules -- even though we are technically "off campus" housing). It's not uncommon for the hot water to go out for days at a time, frequently with no notice.

And the kicker? The lease that I signed forbade running a business from my room. In other words, unless they modified the lease for these Hinman CEOs, they're all in violation.

We *definitely* do not live in spaces that would ever be confused with executive furnishings.

• Very little code financed by the Federal government is ever licensed under either of these two licenses - the choice is basically agency-proprietary (the Federal agency asked for the rights in the contract, and kept them) or company-proprietary (the agency didn't ask for the rights, and the contractor kept them).

NASA uses and produces software under the GPL license.

Any number of of projects funded by NSF, and other Governmental Agency, grants end up licensing software under the GPL.

There is an aspect to this discussion that I don't think gets enough play. The GPL is a great boon to academics who don't have to purchase costly software, and risk throwing obstacles in the way of those who would reproduce their work, or reinvent wheels. This boon comes with the very small cost that the software so produced should be shared with others. I think that this is in harmony with the spirit of Scientific Research, the "standing on the shoulders of Giants" as Newton said.

Note, I wrote that is the limit for electron degeneracy to prop up the star. I didn't mean to imply a star past the Chandrasekhar limit will collapse to a white dwarf.

Science World says ~1.2 solar masses, in agreement with the figure I posted.

It happens that University of California, Davis physics department has a good cosmology group, and I'm a graduate student here. The last seminar I went to about this topic indicated that the Hubble redshift evidence pretty strongly correlated to an exponential inflation due to the cosmological constant, for what that's worth.

As far as singularities go, Roger Penrose proved the Singularity Theorem back in 1965; therefore, all black holes have singularities.

There is a difference between a coordinate singularity and a "physical singularity", although General Relativity (which equates space curvature with gravity) can make it hard to sort out (the proper techniques involve conformal mapping, again pioneered by Penrose) and of course, path integrals and complex analysis. But to simplify the picture, you don't die by going to the North Pole, even though that is a coordinate singularity in a spherical coordinate system. You will die, however, from encountering an object of unknowable physical properties.

Charged and/or spinning black holes have two event horizons; an inner and outer. The outer event horizon is the one dictated by light rays neither spiralling in nor escaping. The inner event horizon is dictated by a worldline unavoidably encountering the singularity.

Physicists actually have no problem with time travel; see the Novikov Conjecture, which basically dictates that closed timelike curves are self-consistent (e.g., you cannot kill your grandfather once you are able to travel back in time; you are now in a closed timelike loop, and past and future are subjective). Any FTL travel == time travel, and there are several interesting possibilities. Robert Forward wrote in his "Dragon's egg" books about using a Kerr black hole to travel back in time, and in "Timemaster" about using negative matter to do likewise (negative matter != antimatter; negative matter has negative mass).

Fascinating stuff. The math is actually extremely interesting; one of the perks of studying physics ;-) (There aren't many). --Adam

Might be a little bit of speculation, but they could do a bit of comparative studies. They could potentially know the size of infants (from nearly hatched egg fossils) and adults. Depending iftyou consider them warm or cold blooded you can roughly estimate their growth rate based on contemporary animals (say gators, birds and mammals) and extrapolate from there.

Also, some bones and teeth exhibit growth rings, like those of trees. Maybe this type of dino had bone growth rings that are clearly visible.

to just do what they do at the University of Maryland and block Netbios and SMB? Seems like it would be more difficult (and costly) for them to just force people to upgrade to XP when a number of security vulnerabilities also exist for that. Sure blocking these services isn't a catch-all solution, but neither is forcing people to use a newer yet still buggy version of Windows.

For those unfamiliar with double checked locking, it's explained here.

The basic claim, is that code like this:
public class Singleton{

private static Singleton instance;

public Singleton getInstance(){
if (instance == null){
synchronized(Singleton.class){
if (instance == null)
instance = new Singleton();
}
}
return instance;
}

}
doesn't work, and the only way to fix it is put the first (instance == null) check into the synchronized block, incurring the synchronization penalty every time the method is called.

You could also simply avoid lazy initialization and instantiate the singleton when the class is loaded.

err... yes we're wired, but we're also wireLESS in these locations. good thing for me the engineering and cs buildings have full coverage (i'm a CE major)

Since visualization is on prime time on /. today, I generated a couple of visualizations of the kernel using a tool I designed for visualizing large data structures.
Look at it by clicking on the third image here if you want some explanations of the underlying research, or go directly here if you prefer.

Enjoy!

Since visualization is on prime time on /. today, I generated a couple of visualizations of the kernel using a tool I designed for visualizing large data structures.
Look at it by clicking on the third image here if you want some explanations of the underlying research, or go directly here if you prefer.

Enjoy!

Moreover, there is free and open-source implementations of those two visualizations: Treemap Java Library and Hypertree Java Library.

Heh. I read a story about that three days ago (28th) on LinuxSecurity (the article is here). A copy of the site, in all its hacked-up glory, is also available here.

I'm kind of surprised, though. You'd think that three days would be enough time for RIAA's 1337 h4x0r5 to both (a) find the perpetrators and retaliate, and (b) fix their site!

I'm surprised this never made it onto Slashdot. It happened a day or two ago, and whoever did it was even nice enough to post some Linkin Park MP3s (oh, the irony...MP3s on the RIAA's own web site). Mirror here. Fark thread here.

I'm not really interested in an argument over how bad public schools are or aren't. I think it's pretty clear to all that they are at least bad enough that grand claims of `vital social benefits' from being forced into such an environment are rather overblown.

Yes, it's important to make sure that your children interact socially with other children. But public schools are neither the only nor a particularly good forum for such interactions. Plenty of other venues exist for meeting other children, including athletic leagues, clubs, churches or synagogues, and so forth. To pretend that the failed academic environment and low standards of a public school should be tolerated in the name of having your children interact socially with other children strikes me as, at best, misguided.

Of course, the only thing really shown here is that if I am allowed to pick any number, and multiply by any factor I want to, I can get any number I want to get!

Of course, the only thing really shown here is that if I am allowed to pick any number, and multiply by any factor I want to, I can get any number I want to get!

Of course, the fact that a homeschooler beat out kids five years older than him to win the national geography bee is just one example of what study after study has shown -- the fact that on average homeschoolers perform several years above grade average in every area of the curriculum.

Against this, you have what counter-argument to make? That home schoolers are missing out on enforced conformity, clicques, bullying, and all the other `vital social experiences' enjoyed by public school children? Thanks, but I (and my children) will pass...

Neat project :-) My main interest is in the forward processes --- I'm hoping to do something involving gesture recognition for my M.S. and take a crack at recognizing sign language for my Ph.D., assuming that I survive that long. We seem to be a long way away from reliable pose guestimation, largely because it's really hard to reliably find joints (like knuckles) in images. The guys over at University of Maryland have a neat system called GHOST, but I'm not certain how well their technique will extend to detecting finer features (like fore-fingers), particularly when there are important details that are occluded.

I work at a neutral buoyancy facility at the University of Maryland -- neutral buoyancy is how NASA trains astronauts to perform EVAs. It uses water to simulate weightlessness. Instead of training astronauts, we design robots to repair broken satellites and to assist astronauts on orbit. As a consequence, we put quite a few computers in very moist environments, and they actually get doused from time to time. The environment isn't salty, but it is highly chlorinated and really warm (the water is kept at around 90 degrees, for reasons I won't get into).

We tend to use embedded machines - PC/104, CompactPCI, etc. These systems are essentially the same technology as desktop machines, the same processors, memory, etc, but have a smaller footprint and tend to use less power. They are remarkably robust. We've had CPU boards that are actually flooded, with the power on. You turn everything off, douse it with WD-40 to dry it out (WD-40 was originally developed to prevent water-based corrosion in electronics, *not* as a lubricant), let it sit for 24 hours, and more often than not it's just fine.

The lesson from this I think is that unless the machine is going to be actually in the spray from the boat, you're going to be okay with a quality out-of-the-box desktop machine. Put one of those rubber membranes over the keyboard - keyboards do tend to die when they get wet. If the machine gets significantly wet, dry it out and maybe hit it with WD-40 or some other water repellant. Other than that don't worry about it.

I recently read and interesting article in SCIAM proposing an alternative to the mysterious dark mater. He calls his theory MOND (Modification of Newtonian Dynamics) where he states that for extremely weak gravitational fields (a < 10E-5 m/s^2), F approaches ma^2. Apparently, his equation is able to explain the stability of may galaxies well without having to use dark matter. It remains to be seen whether his theroy will hold up to serious scrutiny but already, astronomers are using it to model galaxies (using it as a calculation technique instead of an actual law of nature). He has yet to incorporate it in relativity.

More information is available at http://www.astro.umd.edu/~ssm/mond/litsub.html

According to MOND there is no dark matter. So you wouldn't have to worry about its gravitational effect. You also wouldn't have to worry about bumping into it.

The "black paper" makes this conclusion about shared-secret authentication as part of association:

"By passively listening to the conversation, an attacker can obtain two of the three variables in the authentication equation; the clear text challenge string and what the challenge string looks like after it has been encrypted. By plugging these values into the RC4 equations, the attacker can easily solve for the shared authentication key. "

Actually, this is not what their referenced whitepaper describes at all. By observing the authentication sequence, an attacker can forge an authentication by responding correctly to the challenge without knowing the WEP key. This is made possible by the amateur 802.11b authentication scheme, not because RC4 is easily 'solved'.

So, while the shared secret authentication does not hinder a determined attack, it is incorrect to say that it weakens security at all. In the case of unenthusiastic stumblers, it may hinder casual associations with your AP.

To recommend an "open authentication" scheme for improved security seems like bad advice.

I've also written a patch (not yet included, but probably soon, now that feature-freeze is over) that breaks up some of the map's monotony, You can see a screenshot here. (BTW: if this screenshot seems too busy, remember that there are more specials here than in a default game, and that some the pure eye-candy disappears when tile is built upon.)

• Pozzo and Gray first proposed signed executables for the Locus distributed system in 1986 .
• The IBM 4758 uses a signed package mechanism to load executables into the device, Smith and Weingart, 1990.
• Arbaugh built a mechanism for signed executables for SunOS and then FreeBSD in 1994.

If you fear bin Laden or Al Queda I think you're taking the threat a little too seriously. Since the attack on Tora Bora there simply haven't been any new bin Laden videos with actual new footage of the man himself.

On the other hand, America's enemies are not simply limited to crazy Arabic peoples bitter about America's hegemony. They include a very wary China, a not quite mentally stable North Korea, and a beaten but not cowed Iraq. The thing is, though, that they likely already have our secrets. So basically, it's way too late to worry about the possibility that this game is going to give away military secrets.

Whats a math Ph. D. worth these days average in the US? I'd gamble somewhere around $100,000 a year, but please comment if I'm off by a lot.

A cursory glance at Google shows you're probably off by about a factor of 2:

Google cache of Georgia Tech grads' starting salary offers

University of Maryland professors' salaries (math is under CMPS)

• PhotoFinder allows individuals or groups to annotate, edit, and organize large collections of photos. You can layout thumbnails in the usual grid or plot them in two dimensions (e.g., number of people vs. photo quality). Drag a person's name from a list onto their photo to annotate.
• PhotoMesa displays thumbnails of many directories of photos. You can zoom in on any thumbnail (or group) by mouse manipulation.

• PhotoFinder allows individuals or groups to annotate, edit, and organize large collections of photos. You can layout thumbnails in the usual grid or plot them in two dimensions (e.g., number of people vs. photo quality). Drag a person's name from a list onto their photo to annotate.
• PhotoMesa displays thumbnails of many directories of photos. You can zoom in on any thumbnail (or group) by mouse manipulation.

If this is not a problem, how big of an asteroid would we need (roughly, of course,) to cause a problem?

A problem in terms of destroying the moon? Check out http://janus.astro.umd.edu/astro/impact.html and play around with numbers.

The numbers for this one (~100 meters at 10 km/sec) hitting the moon are a 15 megaton explosion, a quake of magnitude 6.4, and a new crater. This wouldn't have any impact on the earth.

Now, if you're talking destruction of the moon, that could be a problem. According to the site, it would take a rock 400km in diameter, travelling at 55km/s, to destroy the moon. A pretty unlikely occurence, in other words.

Assuming this was made of rock, hit land, and only moving at 10Km/sec, It would have been accelerated by gravity during the fall to somewhere around 11.2Km/sec and yielded a crater something on the order of 1Km diameter and 0.2Km deep. (a bit smaller than the crater in arizona) It would have also caused a magnitude 6.6 earthquake.

for other possibilities, see: this page

This also sounds like A project that was also a class at the University of Maryland, Project Endurance. A zipped word file of the final report can be found here This project was the capstone design course for aerospace engineers at the university. Our task was to design a series of 6 missions to explore the lunar base for a period of 90 days each as a prelude to a fully manned base. Hope you enjoy.

"Hey, my SOL quit working !"

"Well, I guess you're just S.O.L."

"Another trekkie showed up for OJ trial jury duty in her Starfleet uniform." Actually it was the Whitewater trial, Jackass! "waaaay too seriously to wrap the mantle of Political Correctness around themselves." ...Then again. The origin of the term "Politically Correct" is Chairman Mao's Great Leap Forward. Face it "political correctness" is no sort of mantel that any intellectually competent person who respects the free interchange of ideas and information would ever have an ounce of respect for. How on Earth can you derride enthusiam for a myth system as brainwashing while at the same endorsing that purile form of mind control you malodorous offal!

While they say all sorts of nice things about nice things about "freedom of expression" and abhorence of censorship, the policy does little to protect such things and everything to retain power for the university. After the nice preamble, the policy quickly turns to a cut and paste of nasty older "user responsibilities" such as don't let anyone else abuse your account. Their privacy statement is essentially, we respect your privacy until we feel that we should violate it.

The most disturbing bits relate to software itself. Their policies revert to the most restrictive license applicable as they claim to respect all licenses specifically, "3. Installing, copying, distributing or using software in violation of: copyright and/or software agreements.", which then points to the above linked acceptable use policy. Does this mean that the Unviersity of Maryland will enforce M$ Front Page's ban on saying bad things about M$ with Front Page? Will they enforce M$'s ban on VPN? They just might, as their acceptable use page while mentioning shareware and public domain software makes no mention of free software.

I'm not sure what kind of community they want to build, but I am sure I don't want to be in it, nor would I want my tax dollars spent on such an organization if I lived there. Shame on you UM. You either don't get it or you don't want to.

While they say all sorts of nice things about nice things about "freedom of expression" and abhorence of censorship, the policy does little to protect such things and everything to retain power for the university. After the nice preamble, the policy quickly turns to a cut and paste of nasty older "user responsibilities" such as don't let anyone else abuse your account. Their privacy statement is essentially, we respect your privacy until we feel that we should violate it.

The most disturbing bits relate to software itself. Their policies revert to the most restrictive license applicable as they claim to respect all licenses specifically, "3. Installing, copying, distributing or using software in violation of: copyright and/or software agreements.", which then points to the above linked acceptable use policy. Does this mean that the Unviersity of Maryland will enforce M$ Front Page's ban on saying bad things about M$ with Front Page? Will they enforce M$'s ban on VPN? They just might, as their acceptable use page while mentioning shareware and public domain software makes no mention of free software.

I'm not sure what kind of community they want to build, but I am sure I don't want to be in it, nor would I want my tax dollars spent on such an organization if I lived there. Shame on you UM. You either don't get it or you don't want to.

I used to work in the WAM and GLUE labs when I was an undergrad at UMCP, and the folks that managed the systems were pretty friendly, if you can get contact info for the current WAM sysadmins, they can probably give you better pointers. In the mean time, there is a page giving useage statistics for the WAM/GLUE cluster.

I used to work in the WAM and GLUE labs when I was an undergrad at UMCP, and the folks that managed the systems were pretty friendly, if you can get contact info for the current WAM sysadmins, they can probably give you better pointers. In the mean time, there is a page giving useage statistics for the WAM/GLUE cluster.

I used to work in the WAM and GLUE labs when I was an undergrad at UMCP, and the folks that managed the systems were pretty friendly, if you can get contact info for the current WAM sysadmins, they can probably give you better pointers. In the mean time, there is a page giving useage statistics for the WAM/GLUE cluster.

I've been wondering about this for a while now, so I think I'll post here.. maybe someone can help me out.

I live in a sea-side town. One of the popular arguements for environment efficiency around here is that an increase in global tempratures will result in the melting of polar ice caps. The melting will cause an increase in the water level such that towns like mine will become submerged.

My problem is this: Water in a frozen state (especially that with salt content) is of greater volume than in a liquid state. While some of the volume can be discounted as the ice floats, the ice within the water will melt and reduce the total volume of the water in total.

Am I crazy or would that mean the global water level would be lowered?

Peter

And Raskin proposed GUI's long before that.

On top of that, Apple had mockups of the Lisa interface long before the PARC visit. see Inventing the Lisa Interface

That apple got the idea from xerox is simply folklore.

hawk

• WEP (Wired Equivalent Protocol)
• Open Systems Authentication
• Shared Key Authentication
• Access Control Lists (MAC Address Lists)
• Closed Network Access Control (LUCENTS Proprietary Access Control)

• WEP has known vulnerabilities allowing someone to decrypt information in real-time after capturing about a days worth of traffic.
• Open Systems Authenticationhas "shown that the authentication management frames are sent in the clear even when WEP is enabled."
• Shared Key Authenitication has shown that it is rudimentary to capture the Initialization Vector since it is sent in the clear as part of a WEP frame.
• Standard Access Control Lists are easily circumvented by an attacker sniffing the network for a valid MAC and thus reprogramming their network card to an appropriate value to gain access to the network.
• The proprietary Closed Network Access Control list that LUCENT (and others)touts as "a system that will not send the network identification (SSID) as a broadcast, thereby mandating that someone KNOW the SSID before they can associate to the network," is inherently flawed since:

1. The most effective strategy would be to put your wireless access points into aIPSEC enabled DMZ, and have your wireless users tunnel into your network using a VPN. If your corporation doesn't already have a VPN infrastructure in place, it's going to cost you some money to implement. Even if you do have a VPN in place, and all of your clients already have the VPN software, there's going to be an extra effort associated with setting up a VLAN for your DMZ. But this solution adds a layer of encryption and authentication that could make a wireless network suitable for sensitive data.
2. Consider using an additional level of authentication, such as RADIUS, before you permit an association with your access points. While it's not part of the 802.11b standard, a number of companies are optionally including some provision for RADIUS authentication. Orinoco access points, for example, can enforce RADIUS authentication of MAC addresses to an external RADIUS server. Intermec access points include a built-in RADIUS server for up to 128 MAC addresses.( EAP (Extensible Authentication Protocol) is used to allow wireless clients to authenticate to RADIUS servers using a single sign-on. )
3. At an absolute minimum, even with it's vulnerabilities, you should enable WEP. Whether you implement 64-bit or 128-bit doesn't really matter too much, as it's not the encryption scheme that's determining how long it takes to crack it, but the number of possible Initialization Vectors. WEP is only a low barrier to entry, but it will keep out many of the casual hackers because there are so many other wireless networks that are wide open and easier targets.

University of Maryland Study: http://www.cs.umd.edu/~waa/wireless.pdf

Fluhrer, Mantin and Shamir Study: http://www.eyetap.org/~rguerra/toronto2001/rc4_ksa proc.pdf

AT&T Labs and Rice University Study: http://www.cs.rice.edu/~astubble/wep/wep_attack.ht ml

I did - (Actually I do have a 7" spark (small, yes) Tesla coil). From all I've read tho,I still have to give Marconi 1st prize for developing and marketing, installing and operating functional, useful shipboard wireless stations for emergency communications. And Hertz was the one who proved the electromagnetic waves predicted in theory by Maxwell before Tesla. See this page.

While Tesla can be credited with inventing the rotating magnetic field, and an unacknowledged genius in his own right, the last 10 or so years of "yada yada Tesla invented this, Tesla invented That yada yada yada" has gone a little to far in the other direction ;)

The "How to write Unmaintainable Code" article on the web is an excellent resource for documentation - much as "Web Pages that Suck is an excellent guide for web designers.

Your organisation - even if it's just 1 man and a dog - should already have a style guide in place. Don't have one? Well then it's easy, there are plenty of good ones on the Net, for Java, C++,Lisp,MATLAB, Ada and many others.

A good list of C and C++ styleguides is here. Just pick one. The important thing is to make sure everyone uses the same one, exactly which one is more a religious issue than anything else. That's an over-simplification, some really are better than others, but at least all the ones on that list have been tried, tested and peer-reviewed.

As for my own opinions, a few issues

• Make variable names meaningful. If you do this, then most of your comments will be metadata, e.g why you did something, and who and when a change was made, rather than what is being done. If you're doing something tricky or unusual, then having a pseudocode preamble can be worthwhile.
• If you can, try to use a relatively high-level language like Ada rather than a low-level one like C. But this is almost never under your control. The Javadoc auto-documentation tool is one of the biggest plusses that Java has over other languages - so if programming in Java, Use It!!

The "How to write Unmaintainable Code" article on the web is an excellent resource for documentation - much as "Web Pages that Suck is an excellent guide for web designers.

Your organisation - even if it's just 1 man and a dog - should already have a style guide in place. Don't have one? Well then it's easy, there are plenty of good ones on the Net, for Java, C++,Lisp,MATLAB, Ada and many others.

A good list of C and C++ styleguides is here. Just pick one. The important thing is to make sure everyone uses the same one, exactly which one is more a religious issue than anything else. That's an over-simplification, some really are better than others, but at least all the ones on that list have been tried, tested and peer-reviewed.

As for my own opinions, a few issues

• Make variable names meaningful. If you do this, then most of your comments will be metadata, e.g why you did something, and who and when a change was made, rather than what is being done. If you're doing something tricky or unusual, then having a pseudocode preamble can be worthwhile.
• If you can, try to use a relatively high-level language like Ada rather than a low-level one like C. But this is almost never under your control. The Javadoc auto-documentation tool is one of the biggest plusses that Java has over other languages - so if programming in Java, Use It!!

I think nobody yet said anything about these things:
1. This might be chinese answer to planned missile shied (Star Wars?)
2. Different research and manufacturing environment than on earth.
3. USA will be blowing comets in the space. And China might have something to say to that.. (remember Star Wars- project and current plans to bring nuclear warheads to space..)
4. If I remember correctly.. There was TV-show for April 1. talking about "third option". Which was to move earth's ruling elite to moon (or mars).

According to researchers at the University of Maryland's Human-Computer Interaction Lab, voice-recognition will never play an important part in our interaction with Information Technology because we construct our spoken communication in the "short-term" part of our memory.

This recent /. thread, discusses a Washington Post article, "A Visual Rather Than a Verbal Future", which details their work.

http://www.wam.umd.edu/~daph/DPR.html
They have some movies in .qt format showing the gators attacking drops of water.

Take a look at Jazz. It has a 2D scenegraph and support for animation and zooming.

Also, you might look at Squeak and Morphic.

My Bio 1001 professor told me that ALL soap is antibacterialogical.

I would also question whether all soaps are antibacterial. Dial, for instance, has the active ingredient triclocarban, which has been used as an antiseptic since the 60s. While that's common in many soaps, not all soaps (particularly "natural" soaps) have it, or something like it.

According to HealthAtoZ.com, over 75% of liquid soaps and almost 30% or bar soaps are indeed antibacterial. While this is a lot, it's far from saying "ALL soaps are antibacterial" (or antibacterialogical, for that matter).

--

Based on the (skimpy) description, couldn't it just as easily have been a Neutron Star fragment or a primordial black hole?

Oh yeah, there is also a cool poster -m

---
http://dubinko.info/blog/

Photomesa is based on the Jazz API (a Java class lib), that implements a ZUI (zoomable user interface), a paradigm sometimes described as 2.5 D interface.

You can use the mouse to move in xy plane und with an extra key press (or possibly via mouse wheel in J2SE 1.4) you change the height of the camera in z direction. This combined with semantic zooming, which means different levels of detail associated with the height, make for very nice user interfaces.

A similiar API has been developed at Xerox France, the VTM library which used by the W3C for the nice IsaViz tool.

Despite IMHO Java still sucks regarding performance, both APIs perform very well with large object scence graphs. Like I wrote, combined with Java's luxury 2D API, it enables us to build attractive user interfaces.

Regards,
Marc