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Last year i took my laptop & gps & a few perl scripts and mapped out the wireless access at my campus (UCSD). I made some maps too. Pretty fun!

http://www.cs.ucsd.edu/~ghamerly/wireless.html

OK, I actually found some substantive evidence:

• An academic paper segement talking about hypertext, which contains a reference to:
• As We May Think by Vanavar Bush, Atlantic Monthly, 1945. Credited in the academic piece as being the first mention in print of hypertextual documents (and you sort of have to have a hyperlink to have a hypertext).

I myself live in a bandwidth black hole which I just happen to be in the center of. So, I actually started researching and buying gear to hook into work's T1, which is about 4.8 miles away. The gear I decided on was two Orinoco (or WaveLAN as they used to be called) cards with Linux boxes to match to keep costs down (besides, Linux makes for a great wireless router). My antennas are 24dBi gain Hyperlink parabolic grid antennas. I already have the cards working in my Linux installations and am ready to hook up the antennas soon. The only tricky part is that my path to work is slightly obscured so I'm hoping I have enough power and gain to be able to punch though. Hopefully the bandwidth gods will look favorably upon me. I've never had a high speed connect at home (and probably never will if this doesn't work :/)

One of the coolest projects I found while researching this was the HPWREN project at UCSD. Check out their pictures, it's hella cool. In a nutshell they are running a 45Mbps (802.11a) wireless backbone across the Santa Margarita Ecological Reserve using mostly off-the-shelf equipment, for the purpose of hooking together the facilities strewn across it. They even have remote cameras hooked in that can be remotely controlled through the network, and other testing stations that send data back to them in realtime.
I dropped an email to the project lead and I asked him what kind of gear they used. He said they used a Western Multiplex Tsunami for their backend, Hyperlink for their antennas and WaveLAN and Cisco Aironet for their PCMCIA cards (you can now see how I constructed my parts list :)) I also asked how he got around mountains and such.
Well, in certain places they have powered relay stations. Naturally I wondered how they were powered, and he said some of them they could get electricity to, but others they actually have solar panels powering the relays. Damn. For you real hackers he mentioned there was a parts list for the solar power array somewhere on the website, but I never bothered to try and find it.

I've noticed some arguments regarding amplifying 802.11, and thought I'd help clear it up. FCC Part 15.247 governs the unlicensed ISM (Industrial, Scientific, Medical) band, and dictates that you can amplify the signal up to 1 watt (1000mw) This gets tricky when you start using directional antennas >6dBi gain though. You may find more detailed info here..

To do this by computer means that you have to keep the on-line ballots linked to the person's name until the polls close.

It's been, what, a little over a week sice IDEA (the Intelligent Design and Evolution Awareness Club, which is apparently "An Affiliated Chapter of the IDEA Center") brought some guy to UCSD to explain how evolution is wrong. sigh.

It's been, what, a little over a week sice IDEA (the Intelligent Design and Evolution Awareness Club, which is apparently "An Affiliated Chapter of the IDEA Center") brought some guy to UCSD to explain how evolution is wrong. sigh.

For more info about the library head here: http://libraries.ucsd.edu/services/info/struct.htm l

Mr. Spleen

For more info about the library head here: http://libraries.ucsd.edu/services/info/struct.htm l

Mr. Spleen

Basically you are referring to the Turing test.

Inevitably, most of this thread ended up discussing AI and the same arguments for and against machine intelligence I've seen bandied about in universities were used here as well.

Obviously, none of us (including those who actually do work on AI) can predict the state of affairs several years from now. However, my personal opinion is that humanity will be unable to create true 'AI', unless it changes its computing and programming models. Which it will, eventually. So you could say I'm maintaining a level of healthy optimism.

As for a an excellent book on the subject of how the brain works, check out Paul Churchland's 'The Engine of Reason, the Seat of the Soul: A philosophical journey into the brain'. I heartily recommend it as a good read. It's not 'cutting edge', in that it was published a few years ago (my printing was published in 1996), and the systems described are not the SOTA. But it's till a great book.

And in the meantime, the public will likely grow more and more annoyed as the results don't come in, fueling a potential backlash against aggressive stem-cell research. While this won't stop research all together, it may lead to a dramatic reduction in funding that could set back the field even further.

I disagree. The same sort of promises were made about artificial intelligence in the 50s and 60s. (We will pass the turing test next year if we work really hard at it.) Of course that never happened, and still may be far away, but I would consider that false excitement a boost for the field, rather than a hinderence, and certainly it led to more realistic promises after it was seen how difficult the problem really was.

Or you can bind them together into a solar collector. Mine is only like 6 CDs across right now but it'll get bigger next time i'm really bored.

Or, i've heard of a science project using an AOL CD as an AM radio tuner. You apparently cut a strip of the aluminum out (across a diameter) leaving 2 slightly less than half circles (well, rainbows) of metal in the more-or-less intact plastic disk. Then you put it in the sleeve with aluminum foil on one face. The foil is in two triangles, seperated by a strip across the diagonal. Connect to the foil on the sleve, and you have a variable capacitor. When the strips are lined up, the capactiance is low, but if you rotate the cd the metal parts overlap and you get capacitance. Neat.

Think about it. Why wouldn't it be a good thing for everyone in the US to get a CD with the AOLinux distro on it every month or so? I just popped in a CD off my spindle of AOL CDs, and it had like 200 megs of blank space on it. They could leave the windoze (and macintosh?) clients intact, and use the other 200 Megs for a compact linux distro. There's no reason they need to use redhat- people like my mom just want to be able to email, surf, write letters, and print. Throw in an MP3/CD burning suite, and you've got just about everything covered. (If AOL wanted to, they could even make DVD playing software that the MPAA, and thus the average consumer, is happy with). I'm sure AOL could fund their own team to put together a little distro which is reliable and secure and targeted to towards people with compaq, dell, hp, or gateway systems that they got off the shelf at frys or compusa (think of it like a PC-to-internet appliance conversion). Ignoring, for now, the implications of having AOL in charge of your operating system (what, like that'd be any worse than M$?), it could be beneficial to the average luser to have a single monolithic system installed on their machine in which all the applications they want are designed to work directly with the OS. From AOL's point of view, it could be nice to have control over the OS that their client is runnig on, and not having to worry about what little component of the system microsoft botched this week. And from the /. perspective, it could be good to expand the linux user base to some signifigant fraction of AOL's. Plus, once you get a bunch of family PCs out there with linux, their 13 year old kids can start using linux to run more than just the AOL client.
Just a question.

If these robots are to be used for monitoring oceans, i do not see why you need them that small in the first place.
Ocean currents are pretty large scale phenomenas, which are often more vertically variable that horisontally. So making a few (a few thousand anyway) fairly large sized buoys which can sink to a pre-determined depth and surface to transmit data on regualr intervals (which would also allow for re-calibration of position). Such buoys are already in progress and limited use for profiling temperature and salinity. I don't see why they can't be equipped with pollutant sensors instead.
There is still the power problem to solve as the floats in use has a limited lifetime though.
In addition the amount of data that would be generated from vast quantities of nano-bots would still require analysis...less of a problems, but enough to create terrabytes of junk data.

"True Names" is one of two of his stories not included in the collection, sadly. I don't know what the other one is.

The second is part of the fix-up novel Tatja Grimm's World, and really makes more sense as part of that novel than as a stand-alone story.

In addition to the two stories (which are both available elsewhere as noted above), there's also a page missing from the collection: see this page containing the missing text.

Silicone, used in breast implants, will NEVER become obsolete, as long there breathes horney men everywhere!

Ah, but who's to say some other material or technology won't come along to supercede silicon as breast implant material?

Then, other than its potential explosive properties, silicon may indeed be made obsolete.

Ok, so I accidentally hit "submit" for the above when I meant to hit preview. Obviously color doesn't work in slashdot. Here's a link to what this looks like: http://www.cs.ucsd.edu/~ghamerly/universe_color.ht ml

History of USENET

Archive for the History of Usenet Mailing List

Usenet Readers and Clients

History of Usenet - Development, people involved

(Yeah sure, anyone could look these up but isn't it easier to just point and click? There is more to USENET history than Google. Also, if you think I'm a karma whore, that's fine. I've got karma to burn.)

When the polar ice caps melt, the ocean level does not rise. Why? because as ice they displace the same amount of space as they would if they were water. It is achimedes' principle. It is what keeps ships afloat, what makes submarines work. Consequently, melt ALL the polar ice caps and our friends in The Netherlands wont notice a thing.

This came from a piece of mistaken research earlier last century by the EPA, where they forgot this. It was an honest mistake, since owned up to, but that has not stopped it entering the public mind, and assorted do-gooders still using it for shock value.

One thing that can get us is if the ice on the Antarctic continent melts. This is possible, but highly unlikely. Ever opened your freezer on a hot day? Do you get more or less ice? That is probably not a concern.

So what are the possible problems? is the ocean level rising? Yes, it is. It rises naturally over time due to sedimentation processes, about 20cm/century, IIRC. The thermal expansion of water due to global warming (supposedly, see the ATOC project for more info) is likely to add a similar amount.

One hopes to disillusion one more person every day....

The press release and a movie of the test setup are here

-Dan

Here is a link to the lab's home page. The project is described briefly here. It would be nice if web-based included those links. It would also be nice if people in the biological sciences followed CS and put their publications on-line.

Here is a link to the lab's home page. The project is described briefly here. It would be nice if web-based included those links. It would also be nice if people in the biological sciences followed CS and put their publications on-line.

Actually, a theoretical computer scientist (Russell Impagliazzo) has already sort of answered the "What if..." question in this paper. It's an interesting paper and the "what if" portions shouldn't be too hard to read, even for those without complexity theory backgrounds.

Yes, we have the gall.

Ask NAVO (the Naval Oceanographic Office) just how much gall they have, mapping gravity over the surface of the seas! In the Old Days, before nifty toys like Satellite Gravity, we used to grid the earth's field by taking in situ measurements all over; *much* of which was done by oceanographic research vessels

Now, a good portion of that gravity grid was done for nice oceanographic or geologic reasons; if you know the density of the stuff below you, you can get a pretty good guess at the shape and contents of the seafloor below, but curiously, the more sensitive and more accurate gravity meters were owned and operated by the USN.

Why is that? Because a good map of the gravity patterns of the sea floor can help with navigating around it, when you *haven't* the luxuries of GPS or loran or other positioning systems.

Submarines!

Gravity maps done by NAVO ships in the Indian Ocean (which have greater detail and precision than the NASA maps, even if they are much narrower and smaller region of coverage) are quite possibly as we speak, helping guide USN subs in the vicinity, as they prepare for any lurking regional threats.

For a quick glimpse of grav fluctuations in the south pacific, as recorded on a Navy Gravimeter (aboard a civilian research ship) try at the bottom

Anyway, most everyone in the Oceanographic community is really excited about satellite gravity, since its coverage is just about universal (except for the poles) but we still lug out the Bell Aerospace meters (ugly black things) from port to port.

If anyone were interested, I could post descriptions of how some or any of these things work, except this is slashdot and this post will probably end up as (Score:-1, TrollFood)

Yes, we have the gall.

Ask NAVO (the Naval Oceanographic Office) just how much gall they have, mapping gravity over the surface of the seas! In the Old Days, before nifty toys like Satellite Gravity, we used to grid the earth's field by taking in situ measurements all over; *much* of which was done by oceanographic research vessels

Now, a good portion of that gravity grid was done for nice oceanographic or geologic reasons; if you know the density of the stuff below you, you can get a pretty good guess at the shape and contents of the seafloor below, but curiously, the more sensitive and more accurate gravity meters were owned and operated by the USN.

Why is that? Because a good map of the gravity patterns of the sea floor can help with navigating around it, when you *haven't* the luxuries of GPS or loran or other positioning systems.

Submarines!

Gravity maps done by NAVO ships in the Indian Ocean (which have greater detail and precision than the NASA maps, even if they are much narrower and smaller region of coverage) are quite possibly as we speak, helping guide USN subs in the vicinity, as they prepare for any lurking regional threats.

For a quick glimpse of grav fluctuations in the south pacific, as recorded on a Navy Gravimeter (aboard a civilian research ship) try at the bottom

Anyway, most everyone in the Oceanographic community is really excited about satellite gravity, since its coverage is just about universal (except for the poles) but we still lug out the Bell Aerospace meters (ugly black things) from port to port.

If anyone were interested, I could post descriptions of how some or any of these things work, except this is slashdot and this post will probably end up as (Score:-1, TrollFood)

Phenomenon, n.; pl. phenomena

This is the program I mentioned in another post. Mserv does exactly what the original poster requested. I used the command line client and Penguin Power, a Linux X10 program, so that I could control playback and rate songs using an X10 wireless remote control. Much better than a web interface, IMHO, because the music can be controlled from a chair in the living room, or from the kitchen, or anywhere else.

CFS and PAST are P2P readonly file systems a la Napster/Gnutella/Freenet. Both had papers in this year's SOSP. Both are based on log(N) P2P overlay routing/lookup substrates.

OceanStore seeks to be a more general (writable) global storage system.

And several P2P conferences have formed and will continue to form.

Some of these projects have been going on for years. So you shouldn't buy the "Academic networking/CS researchers are a bunch of P2P haters" line without a few grains of your favorite seasoning.

Got to hear a talk from Henri Casanova, one of the top dogs working on distributed application scheduleing and simulation software for The Grid. Neat stuff, but, as he addressed in his talk, we're really looking at a network of computers that only people needing massively intensive computations done on highly parallizable problems would find useful. Translation: only researchers in certain fields need this.

Here are some URLs you might find interesting: HPWREN (featured here recently) have a 45mb backbone using western multiplex tsunami kit, and 802.11b access points. They use solar power and batteries to power some backbone nodes.

Some other people using mostly 802.11b kit who will have some information you can use: BAWUG PersonalTelco.net NoCat.net Freenetworks.org

Using 802.11b or similar tech, you should expect each wireless hop to add about 5ms of latency, maybe a little more depending on distance. You can quite easily build a repeater by connecting two bridges together by a X-over cable. You could probably do this with Linksys WAP11 or similar, but over this type of distance you will find it much easier to use something like the high-spec version of Cisco Aironet 350 bridges (the 100mW versions will push the signal a lot further - 25 miles with 24dBi antennas - you can use Cisco's own, alternatives include Superpass (based in Waterloo), HyperLinkTech and others.

Aironet bridges let you set the distance of the link which modifies timing parameters (a slight problem with standard 802.11b over long distances), and their security is better than WEP.

There's plenty of homebrew opportunities for antennas and other related kit, although I guess they're probably of more use to people who don't have a budget to play with (: There's a collection of links on this page with a particular focus on homebrew kit.

Bullshit pal. Poles built a replica of Enigma even before one of the German devices got captured. Learn your history moron.

Let's get it straight that Poland cracked Enigma and built working devices from scratch, long before Turing automated the the decryption process at Bletchley, or Matthew McConaughey recovered the secret Death Star plans from R2-D571.

• I know it's not the same as the entire recovered machine that was captured and used to defeat the natzi germany forces

Lest we rewrite history even more, Poland cracked Enigma and gave a working machine (built from scratch) to the UK well before an actual German machine was recovered. The recovered machine just confirmed how amazingly accurate the Polish device was.

This is a really interesting opportunity for some high-tech to be applied to a real non-military situation. Robin Murphy came here to UCSD and talked a few months ago, and she actually brought (and we got to drive) the tracked one with the flippers in front.

Those things are not easy to drive. One of the most difficult things is getting a perspective on where the robot is in relation to it's surroundings (very rough rubble). This is an ongoing research area for many robotics teams, and one we have been working on also.

The submitter mentioned something about autonomous robots, I think they don't fully understand the difficulty of the problem which robotics researchers are working on. Navigating uneven building wreckage autonomously is an incredibly difficult problem, in general. Especially under the conditions of the WTC rubble. There may be some small parts of the process which can be automated, but I doubt it would be useful in this situation anyway. They were using the robots as probes to discover what was inside areas where it was dangerous for people to be there, so a human is already "in the loop". The real use of these systems is for remote visualization (i.e. show me what's in there) in hard to reach areas.

They didn't specify what types of cameras are being used, but this is a mostly visual problem from my understanding. Most robots have standard rectilinear camera views that are forward facing, unfortunately operation of these platforms is difficult becuause of the restricted field of view and inability to see on the left, right and behind the robot. Multiple cameras helps, but adds significant complexity and disjoint views. A technology which really makes this easier is an Omni-directional Video sensor (which has a 360 deg. field of view around the sensor). These are ideal for "immersed" applications like this, and they literally give the operator a view of the entire space around the bot (except for directly overhead) and allow you to determine the robot's orientation relative to obstacles easily. The same data can also be unwarped and used to create a perspective or panoramic view of the area in real time. A pair of these and stereo software (which also has been done in our lab, [shameless plug over]) can provide a full depth-map of the area. The ODVS has the difficulty of limited resolution (same CCD, larger fov) but this can be supplemented by a Pan/Tilt/Zoom rectilinear camera.

Really the interesting part of research in this direction is the remote operation and visualizations that help the perator navigate through the area to achieve it's goal. This is what my thesis is on, actually.

More info: UCSD CVRR Lab The Page of Omnidirectional Vision and our source of ODVS. Also check Vstone (in Japanese, may need to run that last one through babelfish or something).

Mobile Robots are cool. We even have one that pulls cables for us in the drop-ceiling of our lab... we're slowly working on a web-page for that new one.. I have a cool video for it already but it's HUGE (100M or so). Anyway, I'll shut up.

If you look at these pages, we are talking about $3000-$5500 worth of relay equipment sitting out in the middle of nowhere. What happens if someone comes along and decide they'd want some of that for themselves?

Of course no one would ever want to steal from the Indians... Oh, wait, nevermind.

Please do not refer to "Rage Against the Machine" as just "Rage."

There is a real (and rather well-known in some circles) band named Rage that plays true heavy metal (not that rapcore shit). And not only is Rage a real metal band, they are also very good. Peavy Wagner has approximately one and a half billion times as much musical talent in his pickin' hand, than everyone in "Rage Against the Machine" combined. Except that Peavy can also write damned good songs, arrange the music, and sing it too.

Mixing Peavy's band's name up with RATM is just plain sick. This kind of defamation-by-name-confusion is exactly the reason that trademark law was invented.

This project has been going on for some time now, it's been well publicized in the robotics community and is certainly an interesting offshoot of robotics. I saw a presentation at ICRA (International Conference for Robotics and Automation) last year. Very cool.

It strikes me as rather similar in approach to some of the nano-bot discussions I've read. I.e. build an "assembler" and use that to build other small pieces that can fit together modularly to do what you want. (that's kind of rough, but you get the idea) Interesting parallel in totally different research worlds, although modularity is hardly novel..

The approach does have it's challenges however, the number of independent modules arguably makes the complexity much higher per resultant functionality. A simpler robot could have achieved some of those configurations, and probably more efficiently (power,weight,computational, etc..). Similarly, most robots are rather specifically designed with some task in mind, making general purpose robots is an astoundingly difficult task because of the widely varying requirements of the physical world between different tasks.

I don't mean to bash, actually - I fully support this avenue of research and it's darn cool! Wish I had one..

When the corporations get their own militaries and have wars, I'll be scared.

Do oil mercenaries count?

Oh but we have. Picture. We set one of these up with a mini wireless camera and a bunch of LEDs for headlights. Granted it's not the most powerful thing in the world, but the car we had been using was too tall to fit under some of the conduits in the ceiling. With the addition of a skid plate to prevent filpping and some track tensioners to prevent the tracks from falling off, we managed to pull a string across the ceiling tiles, then use the string to pull any coax or other cables we wanted. And after about 5 hours to get this all working right, we probably saved a good 30 minutes of cable pulling hassel ;-)

But why should't we spend some time having fun with other languages? We shouldn't because time is the most precious resource. Ignorance of how the small things add up to big things is how people who used to earn good money can have no savings and how people become obese. Two weeks spent on Ruby is two weeks you didn't spend on something else. If we followed Dalroth's advice, we would repeatedly waste weeks at a time on other fringe languages as well. Sure it MIGHT pay off but this is the same logic people are criticized for when they spend money on lottery tickets.

I think that learning to live in a budget is simply part of growing up. There is not infinite money to spend, most cannot eat an unlimited amount of junk food without getting fat, and one doesn't have unlimited time. One has to make hard choices. Why is it so hard to accept that people need to make time budgets, especially in light of research that it is essential to get proper amounts of sleep in order to learn.

At the heart of any optimal task switching, there's conceptually a simple, adaptive mechanism that weighs the (measurable) cost of switching tasks against the (expected) benefits of sticking on. Several nice comments on this thread describe this idea for CPU scheduling. On similar lines, I just published a paper on anticipatory disk scheduling (to appear in the Symposium on operating systems principles, October 2001). Idea is that synchronous I/O makes processes issue requests one after another, so the operating system deliberately tries to service many requests from each process before context switching. Unnecessary context switching can get very expensive, and the trick is to outweigh expected benefits against costs while scheduling requests.

This principle can be consciously used in meatspace. We all have unique levels of tolerance and overhead for context switching: measure it! For example, while coding two pieces of software, use a metric such as the number of lines modified in the last hour (diff old new | wc -l): very very hazy, but still useful. Then on each context switch, extrapolate to the next hour based on the past hour. Compare that with the number of lines actually coded for the other project in the next hour. Congratulations, this is your context switch overhead ratio.

Modulo coffee consumption, this number gives an acceptable personalized context switch frequency. There are other factors like taking a quick break to another project, but to a first approximation, this works.

// today's my 24th birthday. just felt like telling someone. //

The heart of the storage component of the Active Web infrastructure is a terabyte server which will come online in Fall 2000. Because of the cost of commercial terabyte storage systems and the need for OS-level monitoring and customization, it was decided to build the departmental terabyte server from commodity components. The terabyte server itself is a dual-processor Dell PowerEdge 2400 running BSD/OS 4.2, with a AMI MegaRAID Enterprise 1600 hardware RAID adapter (four channel, Ultra160), and a link to the gigabit switch. The disk subsystem consists of two RAID enclosures of nine, 73GB Ultra160 disks each. Tape backup support for the terabyte server is provided by a generic PC connected via a two channel Ultra160 adapter to a dual drive Hewlett-Packard SureStore 2/40 tape library with a storage capacity of 3.2TB. Terabyte file systems will be exported to departmental UNIX systems using Kerberos authentication, and to Windows machines via Samba."

(I wonder what Dawkins thinks about the movie).

(I wonder what Dawkins thinks about the movie).

This study (sorry, dead link, maybe you can find the right one) discusses the effects of sleep deprivation on short term memory loss. On the other hand, this one claims sleep deprivation increases activity in certain areas of the brain. And here's yet another story talking about the effects of sleep on brain development. And here's another article claiming naps could increase worker productivity. And, also, this article on the correlation between sleep and learning.

(Sorry for all the Yahoo! News links, I was trying to find the first one, and I came across the latter articles)

There was another study done in the U.K. which linked lack of sleep to a drop in I.Q. levels, but I can't seem to find the appropriate link...

If you're curious as to what other people had to say, the slashdot articles on first two links are here and here, respectively.

-------------------------------------------
I like nonsense, it wakes up the brain cells.

Went off in search after asking the question...

This one has articles from 1981 - 1982:

You forgot this one, complete with JPEGs, MPEGs, and phone numbers: http://orpheus.ucsd.edu/cmrr/lhmedia/

Here is site at UCSD which goes into detail about the "Experimental Verification of a Negative Index of Refraction". Also, here is UCSD's press release the Rueters article is probably based on.