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So show your support for the Hubble Origins Probe, which would cost less than a repair and image 20 times as fast.

It's only a matter of time.

I'd like to take this opportunity to remind everyone about the Hubble Origins Probe, a proposal to replace Hubble with a cheaper and better (and, dare I say, faster) craft:

An international team led by Johns Hopkins University astronomers have proposed an alternative to sending a robotic or manned repair mission to the ailing Hubble Space Telescope. Their proposal is to build a new Hubble Origins Probe, reusing the Hubble design but using lighter and more cost-effective technologies. The probe would include instruments currently waiting to be installed on Hubble, as well as a Japanese-built imager which 'will allow scientists to map the heavens more than 20 times faster than even a refurbished Hubble Space Telescope could.' It would take an estimated 65 months and $1 billion to build and launch, approximately the same cost as a robotic service mission.

Here's the official web site, with slideshows and posters explaining the planned scientific instruments:

http://www.pha.jhu.edu/hop/

In my opinion the original Hubble is mostly valuable for sentimental/historical reasons. From a pure cost/benefit analysis, replacing it seems the best solution in pretty much every possible way.

I'd like to take this opportunity to remind everyone about the Hubble Origins Probe, a proposal to replace Hubble with a cheaper and better (and, dare I say, faster) craft:

An international team led by Johns Hopkins University astronomers have proposed an alternative to sending a robotic or manned repair mission to the ailing Hubble Space Telescope. Their proposal is to build a new Hubble Origins Probe, reusing the Hubble design but using lighter and more cost-effective technologies. The probe would include instruments currently waiting to be installed on Hubble, as well as a Japanese-built imager which 'will allow scientists to map the heavens more than 20 times faster than even a refurbished Hubble Space Telescope could.' It would take an estimated 65 months and $1 billion to build and launch, approximately the same cost as a robotic service mission.

Here's the official web site, with slideshows and posters explaining the planned scientific instruments:

http://www.pha.jhu.edu/hop/

In my opinion the original Hubble is mostly valuable for sentimental/historical reasons. From a pure cost/benefit analysis, replacing it seems the best solution in pretty much every possible way.

NASA's sole purpose isn't science -- if it was, it'd just be rolled into the National Science Foundation. That said, I'm a big fan of spending the money instead on the Hubble Origins Probe -- hopefully we'll see that happen.

Your argument though reminds me a little bit of something I once saw, which said that all/most space advocates were either Saganites, O'Neillians, or Von Braunians (each named after a famous figure in the space field). The descriptions are as follows:

Saganites: "Look, but don't touch." The sole purpose of space endeavours is to increase our scientific knowledge, which will in the long-term lead to the enrichment of mankind.

O'Neillians: The ultimate goal is to turn humanity into a space-faring species. Our focus should be on space settlement

Von Braunians: They want to push the technology to the limit and beyond, and do what's never been done before. Sending huge rockets into orbit and planting flags on extraterrestrial bodies is valuable in and of itself, if only for the glory.

Of course, many are actually some mix of the above. Personally, I'd consider myself a former Saganite, more recently leaning towards O'Neillian.

During the 60s and 70s (the Space Race) the US was predominantly Von Braunian. In the 80s and 90s the US government's space program has been predominantly Saganite, focusing primarily on scientific missions. It's gotten to the point that now many people think that's the only worthwhile thing to do in space. Bush's Vision for Space Exploration is intended to turn the government's space program into a mix of O'Neillian and Von Braunian, doing things like establishing a permanent, self-sustaining moon base.

I'd characterize most private spaceflight folks like Burt Rutan and Elon Musk as a mix of O'Neillian and Von Braunian.

Dude, look here (scroll down past the pictures of my cats). At one point I tracked down their phone number and put it on my website for the convenience of all. I also put Amazon's number there. There's an easy trick to finding any public company's phone number, which is to look at their SEC filings.

I don't quite understand yet how they encode the accuracy. Bit depth? Well, in astronomy there have been for quite some time now two competing efforts to have a scheme of efficiently searching the sky. different outset, two angular coordinates with funny non-cartesian properties. They also come up with a single bit pattern to designate an area on the globe: HTM (hierarchical triangular mesh) and HEALPix. actually the HTM group at Hopkins has close ties to the MS Research group in the Bay area, under guidance of Jim Gray. It's fascinating stuff, as this makes searching large databases a lot more efficient. Something that is useful for the Virtual Observatory efforts.

I think parent is thinking of the Sokal hoax, in which Alan Sokal, a physicist at NYU, wrote a completely non-sensical physics paper and submitted it to Social Text, the leading journal of postmodern pseudo-intellectuals. Social Text accepted the paper and published it, thereby demonstrating their complete ignorance of modern science, which they purport to understand and be in a position to critique. Sokal then exposed their foolishness in a piece in Lingua Franca (sadly defunct). He has links to the hoax article, his Lingua Franca article, the statements by the editors of Social Text, and much other material here

I submitted the story, and because of some sloppy wording on my part a number of people now think that the $1 billion doesn't include the cost of launching the rocket. In actuality, it does include this cost already.

From their poster, here are the figures which go into the cost estimate (written as low/high estimate):

Spacecraft: $135M/$165M
Observatory ATLO: $80M/$100M
Deorbit Module: $5M/$10M
Optical Telescope Assembly: $150M/$210M
SI Mods: $20M/$30M
SI Integration: $5M/$10M
FGS: $30M/$55M
Fee: $64M/$87M
Contingency: $128M/$174M
Launch Vehicle: $130M/$150M

Total: $747M/$991M

Again, my apologies for wording my submission poorly.

Below is a relevant story I submitted a few days ago, which was unfortunately rejected. I might try submitting it (or a related story) again soon, and would appreciate any tips on how I could improve the chances of the submission being accepted (besides, you know, tossing in random comments about Linux/SCO/Doom3):

An international team led by Johns Hopkins University astronomers have proposed an alternative to sending a robotic or manned repair mission to the ailing Hubble Space Telescope. Their proposal is to build a new Hubble Origins Probe, reusing the Hubble design but using lighter and more cost-effective technologies. The probe would include instruments currently waiting to be installed on Hubble, as well as a Japanese-built imager which 'will allow scientists to map the heavens more than 20 times faster than even a refurbished Hubble Space Telescope could.' It would take an estimated 65 months and $1 billion to build, approximately the same cost as a robotic service mission.

On that note, here's another rejected space-related submission which I probably won't be trying to submit again. Someone else is more than welcome to try submitting it, though.

As reported in Space Race News, this Sunday Volvo will be airing a Super Bowl ad comparing one of their new cars to a rocket blasting off into space. The release says, 'At the commercial's end, the astronaut removes his helmet, is none other than Virgin Group chairman Sir Richard Branson, as the ship will be branded Virgin Galactic, with actual takeoffs scheduled for 2007.' Volvo will tout Boldlygo.com in the ad, a web site which will allow visitors to sign up for a chance to be the first passenger on Burt Rutan's SpaceShipTwo.

Allison Okamura's Robot Actuators and Sensors class at Johns Hopkins had to create ArtBots (robots that create art) as their final projects last semester.

Check it out:

http://www.jhu.edu/news_info/news/audio-video/artb ots.html
http://www.jhu.edu/~gazette/2004/13dec04/13artbot. html

Allison Okamura's Robot Actuators and Sensors class at Johns Hopkins had to create ArtBots (robots that create art) as their final projects last semester.

Check it out:

http://www.jhu.edu/news_info/news/audio-video/artb ots.html
http://www.jhu.edu/~gazette/2004/13dec04/13artbot. html

Here's my recently-rejected slashdot submission on this, which has more info:

Hubble Origins Probe: replace instead of repair?

An international team led by Johns Hopkins University astronomers have proposed an alternative to sending a robotic or manned repair mission to the ailing Hubble Space Telescope. Their proposal is to build a new Hubble Origins Probe, reusing the Hubble design but using lighter and more cost-effective technologies. The probe would include instruments currently waiting to be installed on Hubble, as well as a Japanese-built imager which 'will allow scientists to map the heavens more than 20 times faster than even a refurbished Hubble Space Telescope could.' It would take an estimated 65 months and $1 billion to build, approximately the same cost as a robotic service mission.

For example, consider the tale of the Windows 2000 EAL4 evaluation.

Yes, it's a dupe, but forgot about that, take a look at Avi Rubin's home page. Scroll down to that Peer-to-Peer book cover... It says with multiple authors... Does that look odd in a gay orgy kind of way to you too?

One of the authors in this study(http://www.cs.jhu.edu/~astubble/) gives a lower bound of 24(!) for the number of times his projects have been mentioned on Slashdot.

( Getting the world to switch calendars ...)

... refers to The World Calendar (described here) with substantially the same properties, and says "The World Calendar has won the support of many different groups.". And following a few links from the original article leads here, where it says "... the notion of a leap-week calendar was first introduced in 1926 by M. P. Delaporte.".

So this particular notion:

• is very old (at least 50-75 years),
• has had plenty of time to get sufficient support but hasn't,
• and may be a contender for oldest news.

Also, a good website about calendar reform in general.

I think a lot of the problems we have with systems today are caused by the failure of the original designers [brains.]

He apparantly thinks God is a curse word.

I particularly love the arbitrary list of years that have "newton weeks" in them. Yep, that huge list is definitely going to make coding a lot easier (certainly easier than the length 12 list of days per month). And inserting a "special week" in the middle of a year is going to be easier than inserting a day in february. Let's hear it for this inspired new calendar!

</sarcasm>

for you all who're having trouble getting to the actual info page, here it is.

To give you some inside information, the guy behind this idea is kind of a crackpot -- he's a guy who has lots of weird thoughts, but hasn't exactly done much serious research in a while.

And that's why although this may make a good press release, any professional astronomer (or even amateur) knows why we have the calendar we do -- so that each year, the calendar days you are familiar with correspond to approximately where the stars lie in the sky, and the weather season, etc. Ie. every September, the vernal equinox coincides with the rising parallel, the length of the day, etc. etc. Leap days are the way to distribute the extra 1/4 of a day per year into a reasonable interval (once every 4 years).

This scheme of having one calendar with a leap "week" is just another way of shifting around the leap days, and is exactly what an astronomer would NOT want! And his rationale for not having to print different calendars is obviated by having to remember that leap "weeks" occur in years 2015, 2020, 2026, 2032, 2037, 2043, etc...

The current calendar gives some consistency and familiarity -- you can predict how long the day is, what stars are in the sky (within a day or so b/c leap days), and approximately if you're going to need a heavy jacket to go outside in the cold. Under this crackpot new calendar, you have to recompute all these things based on what year it is. Crackpot.

Only, it doesn't. About every 5-6 years or so he inserts an extra week in the calendar between June and July.

No, it's not every 5 years, and no, it's not every 6 years. It's sometimes 5, and sometimes 6. You'll just have to ask him.

So will someone tell me why this is any less difficult than what we currently use?

Only, it doesn't. About every 5-6 years or so he inserts an extra week in the calendar between June and July.

No, it's not every 5 years, and no, it's not every 6 years. It's sometimes 5, and sometimes 6. You'll just have to ask him.

So will someone tell me why this is any less difficult than what we currently use?

This is what happened to me, too, except substitute 6th grade for 8th, and 3 kids for your 5. Add in a summer course of geometry before 8th grade and I was done with Calc BC by 10th grade, at the tender age of 14. During middle and high school I did do the homework, however, although often in the 5 or 10 minutes before class began. This came to bite me in the butt my own freshman year in college, but I perservered, swallowed my pride, and actually began to work for the first time in my life.

Now, a year out of college, I'm in med school. Here I'm surrounded by people who like what they're studying (I do as well), and studying a LOT is the norm. And, at this stage, it actually matters whether I know my stuff, so I put my nose to the grindstone and join in, no matter how much it hurts.

I was quite the academic phenom at a young age (not just in math, I was a SET kid), and this helped me in some ways: I never felt the need to compete in a vicious manner or belittle others' achievements since I'd already had the institutional pat on the back from a young age, so to speak. However, it also made me complacent, and this complacency almost was my failure.

The moral of my rambling, self-congratulatory story? Not everyone who finds the pace and scope of traditional school easy ends up falling by the wayside. We all have to learn how to apply ourselves, and to grasp that being smart is simply not enough on its own. Growing up as a precocious youth one often feels that being gifted means that less effort should be expected of oneself, and that academics is a game in which the goal is to find the least amount of work that will appease the taskmasters. I encourage those who might feel this way to go to a competitive school, and learn from the positive example of their peers that the application of one's talents is as important as their mere existence.

Here is a brief explanation of what EAL levels mean.

We learned a lot about Walmart and Data mining in my database 101 class. And the professor asks "Why do you think Walmart is so successful?"

And everyone says something about leveraging technology and JIT delivery, etc.

Professor Liu says "Nope. Location."
Walmart chose most of their initial locations in cities/regions where there was no other competition. Places where there was no Kmart, no department stores, no malls. And they flourished.

I apologize if this is consider trolling, but I submitted this story a couple minutes ago and since it's relevant to this story I'll post it in here (since it probably won't get approved if this one is already up. If it does make it up just mod it offtopic):

Technical director Dr. Avi Rubin of the John Hopkins University Information Security Institute (ISI) has made a presentation regarding Diebold's voting machine source code (pdf) to the National Institute of Standards and Technology (NIST has been playing a key role in the improvement of voting systems since 2002.) Turns out, amongst other major security problems, Diebold was using NIST's Data Encryption Standard (DES) to encrypt votes and audit logs. DES was developed in 1976 was proven breakable by a "brute force" system in 1998. NIST proposed revoking DES's certification last July and recommends AES or at least 3DES.

Read from page 13. There are some hilarious comments ... or they would be if this weren't a freaking voting machine!

Avi's not the only election judge recording his experiences. So are his minions: http://cs.jhu.edu/~mgreen/election_judge.html

I used Garble because back in Summer 2000, before the grueling years of my physics PhD program began, I took a 15,000 mile roadtrip around the USA. During most of the driving I had my laptop connected to my GPS, pinging it every minute (through a simple bash script) getting a latitude and longitude. After my trip I compiled all the points, and used IDL to make some nice plots from the data. IDL was cool because I could easily set up map projections w/ my latitude/longitude data, overlap satellite images, and even plot country/state borders (IDL costs $$$$$, but Johns Hopkins University physics department has a large client license on the student terminals, which is nice). Check out my final Mercator Plot and Satellite Perspective Plot. My route is in red (chronologically going clockwise around the country), yellow circles are where I spent the night.

You can read my unfinished online journal here. Yeah, it's been a few years since the trip, and I do really need to finish that journal and clean up the ugly page layouts.

I used Garble because back in Summer 2000, before the grueling years of my physics PhD program began, I took a 15,000 mile roadtrip around the USA. During most of the driving I had my laptop connected to my GPS, pinging it every minute (through a simple bash script) getting a latitude and longitude. After my trip I compiled all the points, and used IDL to make some nice plots from the data. IDL was cool because I could easily set up map projections w/ my latitude/longitude data, overlap satellite images, and even plot country/state borders (IDL costs $$$$$, but Johns Hopkins University physics department has a large client license on the student terminals, which is nice). Check out my final Mercator Plot and Satellite Perspective Plot. My route is in red (chronologically going clockwise around the country), yellow circles are where I spent the night.

You can read my unfinished online journal here. Yeah, it's been a few years since the trip, and I do really need to finish that journal and clean up the ugly page layouts.

I used Garble because back in Summer 2000, before the grueling years of my physics PhD program began, I took a 15,000 mile roadtrip around the USA. During most of the driving I had my laptop connected to my GPS, pinging it every minute (through a simple bash script) getting a latitude and longitude. After my trip I compiled all the points, and used IDL to make some nice plots from the data. IDL was cool because I could easily set up map projections w/ my latitude/longitude data, overlap satellite images, and even plot country/state borders (IDL costs $$$$$, but Johns Hopkins University physics department has a large client license on the student terminals, which is nice). Check out my final Mercator Plot and Satellite Perspective Plot. My route is in red (chronologically going clockwise around the country), yellow circles are where I spent the night.

You can read my unfinished online journal here. Yeah, it's been a few years since the trip, and I do really need to finish that journal and clean up the ugly page layouts.

Funny, we were talking about the 1.5 APIs last week here at work, while talking about migrating our apps over from 1.4.x. This site Official Java Programming Documentation gives you a ton to think about. I rem when we were on 1.2...

CB*($#@

Here, all you freeloaders ;-). I'll take it down later today.

I just spoke with him on the phone, too; cool guy. I don't think he was expecting anyone to actually call him :-).

I mostly write technical documents. troff takes less effort to write, I'll continue using that instead of AbiWord/OpenOffice/MS Word. WYSIWYG is generally not that useful if you do mainly structured documents or if you need fine control of typesetting. Typesetting languages with the right scripts are generally the easiest. If you need purely structured documents then DocBook-SGML is not a bad route to go. (SGML is fancier and more human-friendly than XML, which is what you really want if you are manually editing tags)

Also when doing resumes you really have to make sure that the resume looks correct in Wordpad, Word97 and Office2k/XP. Seems that these are what recruiters use (wordpad appearing to be the most common). Hint: save as word97 RTF and rename .rtf to .doc. This will make it load correctly in wordpad, without getting too fancy/bizarre on the formatting that Office2K likes to put in.

Recruiters seem to hate PDFs (I guess they prefer file formats with macro viruses). Although I've had a great deal of luck with HTML. Mostly I just do my resume in troff and provide it as PDF to the manager/engineers and HTML to the recruiters and everyone is happy.

Guide to doing your resume in troff (and taking advantage of macros to painlessly customize your resume).
Your Resume: Part 1 Your Resume: Part 2

If you do a lot of technical documents these tools work well with troff (or LaTeX):
Graphviz for doing automated diagrams
Gnuplot for doing scientific graphing (it can output postscript and ascii)
TGIF a 2-d drawing tool with a light-weigh intuitive UI.
gEDA for schematics and pcb layout
xcircuit extremely powerful 2-d drawing tool. originally designed for schematics, but is useful for any sort of diagram.

Also if you were wondering: Résumé == Curriculum vitae (CV)

Just a minor point but don't forget about Johns Hopkins or Duke to name a few universities founded by rich men.

One of the reasons that cities pay so much to help build stadiums is because the stadium brings so many people to the area it creates a somewhat massive economic boom in the area, which over time can be worth more money than the cost to build the stadium.

5. Setting a Low Bar

An important part of the CC is the Protection Profile, a standardized statement of requirements for what a given kind of product should do. In many cases, these standardized documents set a low bar for security. Windows 2000, for example, was certified against the Common Access Protection Profile[3], which

... provides for a level of protection, which is appropriate for an assumed non-hostile, and well-managed user community requiring protection against threats of inadvertent or casual attempts to breach the system security. The profile is not intended to be applicable to circumstances in which protection is required against determined attempts by hostile and well-funded attackers to breach system security. The CAPP does not fully address the threats posed by malicious system development or administrative personnel.

Jonathan Shapiro at Johns Hopkins has done a great job of translating that into colloquial English[4]:

Don't hook this to the Internet, don't run email, don't install software unless you can 100% trust the developer, and if anybody who works for you turns out to be out to get you, you are toast.

In the real world, Windows 2000 systems require protections beyond the low bar set by the CAPP. Nonetheless, defense buyers are free to purchase and deploy off-the-shelf Windows boxes: They simply check the box marked "EAL4". Checkbox security is fraught with risk.

Check out this link: Understanding the Windows EAL4 Evaluation

...EAL levels run from 1 to 7. EAL1 basically means that the vendor showed up for the meeting. EAL7 means that key parts of the system have been rigorously verified in a mathematical way. EAL4 means that the design documents were reviewed using non-challenging criteria. This is sort of like having an accounting audit where the auditor checks that all of your paperwork is there and your business practice standards are appropriate, but never actually checks that any of your numbers are correct. An EAL4 evaluation is not required to examine the software at all.

EAL doesn't really mean much. At least, not until you get up to the higher levels. It's basically so that government departments can have a check-list requirement for any software they buy or comission.

I work in the PCB (Printed Circuit Board) industry, and I've looked at the Pad2pad website before. The problem with them is this - they give you software to create a board in, but it only outputs in their proprietary format. That means your design can only be fabricated by pad2pad, not by anyone else. So, once you've designed in their software, you are locked into ordering boards from them. You cannot order them anywhere else unless you re-design it in another software package.

There are older DOS freeware PCB layout packages called easytrax and autotrax available from Protel , as well as a free 30 day demo of their latest. There is also a Linux PCB layout package available. These packages output gerber data, which is the industry standard data format for circuit boards. It is also an open format (rumor has it /. people like that sort of thing). This means that you can send your design to any PCB shop in the world, and they can read it as easily as you can work with a *.bmp.

You can even send your gerber data to pad2pad, and they can make your board from that, though they would prefer if you used their software. After all, if you don't, you'll be able to get the boards make somewhere else if you don't like their service.

And that would be so unfashionable - doncha know proprietary lock-in is all the rage these days?

You hook the int 2 (?) and int 3 during the run, so your code gets called before the debugger's breakpoint handler, amongst other techniques.

Have a look at this paper and be enlightened :)

CAD link 1

CAD link 2

PCB link 1

PCB link 2

PCB link 3

I couldn't find any COGO links. But then, I searched for COGO in general, and the only suites that came up were DOS and Unix. I can't comment on the quality of the Linux software, as I don't do this stuff. But I wasn't under the impression that Windows was the premier CAD environment (all the CAD and Database guys at work have big Unix workstations).

You're exactly right about getting kick-backs, as well as the fact that they collect royalties for every book they put out. My Biology teacher is friends with the author of my Biology book (this is the reason that we use it, actually) and he has stated that to stay current with the class, you need the new book.

Not every professor is like that though.

I actually had one professor who personally refunded the royalty portion of the price of a new book. It was amazing. Anyone who bought a new book, he handed $5. He didn't like making money off book sales to his students.

He's a very nice guy.

Because I know that's the first thing I clicked on, and it was slow then. Here's the mirror.

And likewise there should be no further possibility he could even be a professor in mathematics from either University of Maryland, College Park , Johns Hopkins University , or many of the other nearby colleges/universities I'm too lazy to link (George Washington University, Towson University, Loyola, University of Maryland, Baltimore County, etc etc).

I mentioned this yesterday as well, but for an idea of what qubits are you can take a look at my currently unfinished Java Quantum Computation applet. As of now one can only do single-qubit operations, but eventually I hope to have a demo of quantum teleportation (teleportation of a single qubit, or spinor, that is).

This applet will give you an idea of what qubits are. Essentially they're a 'spinor' which in quantum-mechanical terms is a 2-element discrete wavefunction. In lay terms, this just means a set of two complex numbers (properly normalized). They are also displayed in a more visible representation, called the 'Bloch Sphere'.

This applet will let you take any input qubit, and operate on it with 6 different single-qubit quantum gates, and see the resulting qubit.

Look at the two qubits represented on the Bloch sphere. The yellow vector represents the qubits. The red dot indicates a classical 'zero' and the blue dot indicates classical 'one'. In classical computing any bit can only point exactly to the red or blue dots. In quantum computation a qubit can point anywhere on that sphere.

[For the mathematically curious, a qubit is 2 complex numbers, which would be 4 independent parameters. However, the sum of the modulus squared of each complex number must be unity, so that constraint leaves only 3 free parameters. Secondly, the entire qubit can be multiplied by any arbitrary phase constant (e^i*gamma) which changes the spinor but not its relative values. Hence, there are only two parameters for each qubit that really matter, so it can be expressed in 2D, mapped nicely to the sphere.]

In classical computing there are only 2 single-bit gates - Not and Buffer (actually, I never formally studied computer science, so someone please correct me if this isn't true). 'not' flips the bit, 'buffer' keeps the bit unchanged. In quantum computing there are infinitely many single-bit gates, some of the common ones are demonstrated in the applet. Basically, these gates can control how relatively 'one' or 'zero' the bit is by the superposition, as well as change the relative phase.

Anyway, I should be adding in two-qubit operations soon (like the infamous controlled-not) and hopefully get to something worthwhile.

So this applet isn't very useful for actual simulation of quantum computation yet, but it will you give an idea of what qubits are and how they can be represented.

Anyone interested can try it out here . You can take any valid input qubit, operate on it with any of six different single-qubit operators, and then see the output qubit. Qubits are represented as both complex spinors and on the Bloch sphere.

Next up is to add two-qubit operations, then work to having a controllable demo of quantum teleportation. I'd appreciate any constructive comments, if anyone would like to add some input.

Anyway, this is an interesting question and problem, and I had to research this topic a few months ago myself, and came up with the Secure Multicast IETF that is dealing with reserach and secure multicast standards. One of the bigger research platform seems to be Secure Spread, a framework derived from the Spread Toolkit for reliable muticast. These are good places to start with the problem of secure multicast I think, although Secure Spread seems not to be under heavy development since 2002.

Since the original poster mostly talked about means to provide secure authentication and/or key distribution (dongle and smart-cards), I would like to point out that the main problem of secure multicast is rather providing

• a secure way of authentication and authorization of clients trying to join a multicast group
• a secure way to distribute shared keys for members of the same multicast group
• a secure way to re-key shared keys for all members of a multicast group
• a way of stopping access to the multicast data for specific members of a multicast group that should be rejected further data access (due to administrative decision) while maintaining the rest of the multicast group members and functionality

Neither IPSec, the number one secure IP protocol, provides for that, nor do IGMP or multicast routing protocols which are used for multicast group management. If you manage to solve this, the actual problem of distributing and managing account data to customers will be a bliss. (Oh, and since you involved the /. community in this problem, I expect you to provide your solution as free software, or at least open source, to the public... .)

Hitler could never have drunk tea at No.10. The Battle of Britain had already finished long before Enigma was cracked. The Bob was more important as a moral booster and proof that the Luftwaffe could be beaten rather than saving the nation, that would have been the job of the Royal Navy.

Both the Luftwaffe and Kriegsmarine stated that there was little they could do to stop the RN breaking into German Invasion lanes once in the lanes it would be easy for the navy to sink the invasion barges with there wake alone so Sealion was called off. Air superiority was of secondary concern to naval superiority. The threat that faced us earley on in the war was not as severe as has been suggested.

Turing never stopped an invasion. Turin's big contribution was to allow Military commanders to decide what resources to commit where and when, invaluable for a country with limited resources especially in the Mediterranean. Turing undoubtedly shortened the war the only debate is by how much and how many lives saved.

A java enigma machine to play withbut I want a bomba simulator.

Well, the software that runs LiveJournal.com (let's call it LiveJournal, because that's its name) rules. It's infinitely configurable, because for one, it is designed that way, and for another, it is open source. It can be deployed on any website. See the Hopkins Weblogs, for example.

See my weblog on LiveJournal.com. What more does a blogger want?

I'm surprised they don't mention LiveJournal in that blog software chart of theirs. I have evaluated Movable Type, and I think LiveJournal is better.

My understanding is that - although smoking is a risk factor for the condition - Barrett's esophagus is most frequently associated with Gastroesophageal Reflux Disease (GERD).

So really, Barrett's is not among the "effects of being [a] longtime smoker," but rather a condition that many people with GERD develop that is associated with a greatly increased risk of developing throat cancer later. So lowering the number of people who smoke really wouldn't decrease the need for this test.