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There was an article in the IEEE Spectrum magazine this month about how a space elevator was inevitable, and they acted like it was mere weeks away and a completely done deal, all wrapped up and ready to go. At least that was how the title came across. So by the end of the article (slashvertisement was more what it felt like) they had disclosed all of the tons of technical hurdles to doing the magical space elevator. Its a "Scooby Do" if I ever saw one. Here's the slashvertisement: http://www.spectrum.ieee.org/WEBONLY/publicfeature /aug05/0805spac.html

This month's IEEE Spectrum features an article by Bradley Edwards who studied the near-term feasibility of a space elevator under a grant from NASA. His conclusion is that it could be accomplished in as little as 10-15 years and for as "little" as $10B (meaning little enough that there are several individuals on Earth who could fund it privately). Of course, the major technological limitation is the nanotubes. He suggests "spun" nanotubes (like yarn) or nanotube composites (and he contends that if one of these broke near the top, it would not be the end of life as we know it -- it's a ribbon that would loft gently down to Earth and burn up in the atmosphere). He even addresses storms, terrorism and space-borne threates. It's a good article and somewhat technical (written for engineers). His conclusions are quite credible, and probably more informed than your average Slashdot debate.

This month's IEEE Spectrum features an article by Bradley Edwards who studied the near-term feasibility of a space elevator under a grant from NASA. His conclusion is that it could be accomplished in as little as 10-15 years and for as "little" as $10B (meaning little enough that there are several individuals on Earth who could fund it privately). Of course, the major technological limitation is the nanotubes. He suggests "spun" nanotubes (like yarn) or nanotube composites (and he contends that if one of these broke near the top, it would not be the end of life as we know it -- it's a ribbon that would loft gently down to Earth and burn up in the atmosphere). He even addresses storms, terrorism and space-borne threates. It's a good article and somewhat technical (written for engineers). His conclusions are quite credible, and probably more informed than your average Slashdot debate.

You really don't know what you are talking about. Cars are one thing, aircraft and spacecraft are totally different. For example I just purchased a 1947 Cessna 140. I would stack that plane against a brand new model Cessna and probably win. Even after almost 60 years that plane stacks up well considering how much it can carry and how much fuel it uses. It is certaintly very air worthy. That is because aircraft are inspected EVERY year for corrosion and problems (they call it an annual). They are repaired if a problem is found and usually they are better than new. I know for a fact I can take my 140 into fields that a brand new 172 wouldn't dream of going into. The 172 is about 15 knots faster, it also burns twice as much gas (at $3.50/gal). Same thing with the shuttle. It is inspected very closely. Considering what is going on to push it up into space and return it, I think it is about as safe as it can be. New doesn't necessarily mean better.

20 years for a car is a very long time, 20 years for an aircraft really isn't. My son for example just flew on a 35 year old 747. B-52 jets used in Iraq were built in the 1950s (much older than the pilots flying them). Still safe. Cars will last indefinately too if you keep corrosion down and replace parts as they go bad. Most people get rid of cars because they are tired of them or want new features. Some cars do suck from the begining, however.

The design of the shuttle makes as much sense today as it did in the 1970s when Nixon signed the bill to start construction. He was badgered into doing it. Throughout the shuttles history it has been criticized. I'd ditch the environmentalist change on the foam for the tank (makes it flake off) and keep the shuttle until a space elevator can be built out of nanotubes HERE

Either that or bring back Saturn V rockets. They can take a heck of a payload at a time.

maybe tens of thousands of individual lifts

Two initial lift and a stitcher/climber
The Plan
All other materials are lifted using the initial 20cm ribbon cable

A more direct link: A Hoist to the Heavens

Of course, speaking of the Boomers, I fear that my generation (I'm 28) might be one of those unlucky historical examples of one which didn't get to do jack shit because they were so busy catering to the needs of their wealthy elders while trying to patch up the disasterous debts they left us. By the time they start to croak en masse it'll be too late to do anything all that interesting -- we'll be too old and too unimaginative, left only with the shadow of the dreams we once entertained.

I used to think the same thing (I'm 42). I remember double digit infation, and things looked pretty bleak. Only recently have I begun to look back at how life has changed since then, and how change is (usually) a gradual process. Most of the big changes that have occurred were unexpected, so the place to look for the future is not the present.

(BTW) The August issue of IEEE Spectrum has a interesting article on space elevators, which could really sidestep the shuttle debate and render it mute.

Funny this topic came up, I just read an article talking about it in Spectrum - A Hoist to the Heavens.

We know of no method to make the multi-kilometer long nanotubes necessary for the space elevator. We are not even close--we need a multi-order of magnitude breakthrough to make this happen.

According to the article they can manufacture very long cables of insufficent strength, or very short sections of sufficient strength. Its only a matter of time before the two come together. I'm sure this kind of daunting task was similar to that when the idea of a trans-oceanic communication cable was first proposed. Now they have very long fiberoptic cables crossing the oceans all over (I saw a documentary on this, its not a trivial task either).

How the hell do we know that industrial prodution of mega-nanotubes will be environmentally friendly?

I doubt production of trans-oceanic fiberoptic cables is particularly green, but we do it anyway because in use they are certainly a better way of communicating than many alternatives. Instead of emailing someone across the ocean, we could always go the paper-only way, packaging all the handwritten mail and ship/flying it over, which I think is very easy to argue is a much less "green" way to do it (need trees for the paper to write on, need fuel for the transport, etc).

The elevator as argued in the above article is ground powered so it doesn't need to carry or burn its own fuel on the way to orbit. This has got to be more green than the conventional rocket way of doing it.

You can't build the space elevator from the Earth up. You have to start at geosynchronous orbit. This means that we will need conventional rockets to move the entire mass of the elevator into orbit.

Not exactly, again according to the article, they send up a "minimalist" version of the elevator first (one only sufficent to lift a very small crawler). After that crawlers start from the ground and head up, adding mass/strength to the elevator ribbon as they go.

In other words, we need a conventional green launch platform before we can build an envionmentally green elevator.

I don't think one depends on the other. I doubt if conventional launch platforms can ever be "green", as their very conventional nature requires burning a big pile of not green fuel. I would think they are more concerned with energy to weight ratios and such rather than how clean it all is.

I agree with some other threads in this topic that the launching of rockets is merely roundoff error, if that, in the amount of pollution generated via more ordinary means. Just think of how much jet fuel is burned each day, or how much coal ash is created each day.

Personally I'm astonished that trans-atlantic and trans-pacific fiberoptic cables exist, but in fact they do exist and are all over. If someone can build and make a working space elevator, I say all the more power to them.

This was already discussed in the March issue of IEEE Spectrum. I'm tickled pink to see that engineers aren't the only ones paying attention.

No more. The latest 3-D volumetric displays overcome this issue. These devices gives a visual clues to your brain to recontruct the 3-D image. Couple of months back there was feature story in IEEE spectrum on the recent 3-D technology advances. Here is the link

http://www.spectrum.ieee.org/WEBONLY/publicfeature /apr05/04053d.html

The real difference between software engineers and other types of engineers is that software engineering is not a profession. There is no general certification to enter software engineering, and there is no required professional organization with a fixed code of ethics.

Of course, does anybody here really think government regulation would make software engineering better?

The real difference between software engineers and other types of engineers is that software engineering is not a profession. There is no general certification to enter software engineering, and there is no required professional organization with a fixed code of ethics.

Of course, does anybody here really think government regulation would make software engineering better?

If you're looking for the short answer without having to do excessive research and wade through the crackpot stuff:

-Ionizing radiation: far ultraviolet, x-rays, gamma rays (wavelength 280nm or less )
Wavelength is small enough to cause cellular damage from free radicals. Definitely proven to cause cancer.

-microwave radiation: wavelength 30cm(1GHZ) to 1mm(300GHZ)
Not small enough to cause direct cellular damage (i.e. not ionizing). Exposure at high levels can cause burns. Microwaves pose a particular danger to the eyes, parts of which are much more sensitive to "cooking effects" than the skin and have no surface nerves to warn of overexposure. Cell phones and WAPs do not put out enough power to qualify as dangerous in this regard.

No conclusive link has been demonstrated between non-ionizing radiation and cancer.

We should seriously downsize NASA to free up as many engineers (especially young ones) as possible to do PRODUCTIVE work in the commercial and academic sectors.

Great idea. With unemployment for engineers still near all-time highs, let's dump some more on the market.

Maybe, just maybe, Consumers Union, the Electronic Frontier Foundation, the Institute of Electrical and Electronics Engineers, or at least somebody who represents the needs of the user?

Check this one out.

New directions in cryptography.
http://ieeexplore.ieee.org/Xplore/login.jsp?url=/i el5/18/22693/01055638.pdf

Is there a list round of the famous pieces yet?

I was going to mention it if you didn't.

And everything else he wrote. One of the only authors whose material I reread often. The most recent of his short stories
"fast times at fairmont high" and the following free online story cover alot of his more recent consensual reality ideas, absolutely brilliant.

http://www.spectrum.ieee.org/WEBONLY/publicfeature /jul04/0704far.html

Your book is a style guide: a reference of background information and pointers how best to code

Did you even skim the pdf before posting? While it does include a coding guidelines section with each section, it also has a commentary section, language and standard comparision, etc... For example, when was the last time you read a style guide went into a lengthy discussion on the probability of floating point errors based on implementation. Given your current position, Knuth and Strang produce texts that are useless as they are not a cookbook for produce {latest widget} in {latest language}.

Your post does raise the more interesting question of finding the the soul of computer science.

I don't want my computer to clique me into a particular "community".

I want it to be a toolbox that allows me to be a part of many communities I choose to join.

And if you don't like the software available, it is, you know, possible to write your own, to your - or the world's[1][2][3][4][5][6] - standards of function, style, consistency, robustness, and hipness.

So is it Windows's fault that it's too broad and not restrictive enough on new tools, or is it Mac's fault that it's provincial and overweaning?

Ever transfer files from one computer to another with a crossover cable? It's really nice to do it wirelessly- hence ad hoc mode.

For the layman's overview of ad hoc mode check out this overview if you want the nitty gritty read the standard itself

It is a real mode. And would be quite usefull if chipset manufacturers bothered to implement it correctly and test interoperability.

Here's a good writeup about it.

Abit were total dicks about giving me any help to diagnose and fix the problem, though. Don't know if any other company would have been better.

IEEE Spectrum in May (05) ran a great article on fusion inside a jar:

http://www.spectrum.ieee.org/WEBONLY/publicfeature /may05/0505sono.html

Something to read for those interested in current fusion ideas.

in true...this is just an initial step in biological modelling. We yet need more experimental data to develop reliable models, and build oriented models. Real biological systems are much more complex than our modelling capacity today. References?? http://www.nature.com/msb/index.html http://www.fosbe.org/ http://ieeexplore.ieee.org/xpl/RecentIssue.jsp?puN umber=9270

from here, which is the 802.11p spec (TFA says they're using 11p), it's got a range of 1000 meters, or 1km. No idea where the 30 stuff came from.

if everyone were to agree on a tag set and apply it consistently, and tag everything of possible business interest, then yes, WebFountain would not be so relevant...and people would also need to tag for things that they don't even know will be businesses in 50 years [...] We'll see if that pans out!

...in IEEE's magazine Spectrum..

Bill Woodcock of Packet House travelling the world and setting up Internet connections in remote locations.

Fortunately, most standards bodies got reality: charging outrageous fees for copies of their publications was horribly cost-ineffective for the industries that they supposedly served; there are other ways to raise those relatively small sums.

Today most standards documents are available online for free. The standards bodies seem to have survived the change. Maybe it's time for academic publishing to do the same.

> 1 square km for 20,000 households; 20sq km for a city of Edinburgh

So, 20sq km for 450K folk, or roughly 13,000sq km for the US. US Coastline is 6000 km w/o Alaska, or 13K with Alaska. A double line of these off Alaska's coast would about do it for the US. How far off the coast should these be?

Of course, entire ocean's about 320M sq km, and we've had transoceanic communication cables a hundred years before my birth...

They talked about this sort of thing in the March IEEE Spectrum cover story, Star-Crossed.

Networks are not governed by Moore's Law, instead there is Edolms Law, a theory on the growth of computer networks.

"If we project forward, Edholm's Law says that in about five years 3G (third-generation) wireless will routinely deliver 1 Mb/s, Wi-Fi will bring nomadic access to 10 Mb/s, and office desktops will connect at a standard of 1 gigabit per second."

--Steven Cherry - Edholm's Law of Bandwidth

So while in 6 years Lucas's network may or may not be sufficient for his needs, by outside standards of network speed it will remain sufficient.

Mobile phones will really start to work for us when they can use any of the radio networks available, handing off seamlessly. UMA is the mobile telco's 3G coopt of WiFi. SCCAN is the WiFi coopt of 3G. And the IEEE's 802.11e makes WiFi itself suitable for heating up spots in the mobile convergence mix. There's even Bluetooth routes to global telephony. It'll take a few years to work at all, but we're looking at the ream form of the emerging mobile platform.

I'd like to see better summaries of research published; something available in between reading all the abstracts and interesting papers in the top journals of the field and just reading the occasional flasgship paper in /Science/ or /Nature/.

For the IEEE, I've found the maganizes published by the individual societies give a good high-level overview of what's in the journals. My favorite is the IEEE Signal Prccessing Magazine.

Of course this probably isn't the area your interest in, and it probalby doesn't help :)

Brett

There is another way to make a "nuclear battery", which was discussed in the september 2004 issue of IEEE's Spectrum magazine (could not get a link...): by ionizing a bit of matter, it gets attracted to other matter (think static electricity). So you ionize a flat, piezoelectric part that's attached at one end over an unmovable base plate. The attraction makes the loose end of the part strain down to the base, and the piezoelectric nature of the part makes it generate electricity on the way.

ACM Software Engineering Code of Ethics
IEEE Code of Ethics
Even more codes of ethics!

Link to 802.1Q std (just in case people thing only the RFC's are available free). Oh - if anyone actually intends reading it, take a *LOT* of V or Red Bull or whatever passes for caffiene in your neighbourhood

1. Organise peer review - it's not like it organises itself. You have to find and select peers without conflicting interests, but with adequate subject knowledge. You have to chase them for deadlines and give them help as needed.

I'll grant you this one, possibly.

2. Edit. In real life, scientists and academics are often not very good at writing cogently. Someone needs to help make it readable.

Peer review also reviews readability as weell as accuracy. A poorly-written paper can get knocked back (particularly if the content isn't that exciting) just as easily as a paper with poor content. My boss would have my balls on toast if I submitted a paper that was not clearly written.

3. Copy Edit. And someone needs to fix the grammar and spelling.

Again, in my experience it's the peer reviewers that do this. If something is that badly written, it gets rejected anyway.

4. Technical Edit. Someone needs to check all the mathematical formulae, diagrams, drug names, etc. to make sure nothing's wrong.

Again, it's the peer reviewers, not paid editors, who do that, as much as they can. Most of the time, only researchers active in the same area are capable of doing the checking. Maybe it's different in the world of medical journals, which you seem to be talking about.

5. Statistics. In many fields, the publisher will use a statistician to confirm that there are no statistical errors in the paper.

Not in my field.

6. Original writing. Most academic journals, and all the major ones include a considerable amount of original content as well as research papers. All that needs to be written and edited.

If that content is really useful, it can stand on its own and people will continue to pay for it.

I can't think of any journal that today asks authors to give up copyright to papers they submit. It's a choice.

You obviously haven't submitted a paper to the IEEE, then. They insist on copyright assignment.

Maybe medical journals (which seems to be what you're familiar with) are somewhat different to other types of scientific journals. For one thing, I gather many of those who submit to them are practising doctors rather than full-time researchers. Anybody who needed the kind of help you're describing as a full-time researcher wouldn't last very long at it.

On similar theme, current issue of IEEE Spectrum has article on How to Hook Worms

Whether or not the display will be better than existing ones is not important.
It's got NANOTUBES in.
If it has nanotubes in the title you can just get any crap published. It's 4 years now that I do research about nanotubes, so I profit a little myself there.

If a product has nanotubes in (remember the infamous Nanotube Tennis racquets?) it creates a ridiculous amount of attention.

And if you write "nanotube" on any absurd research proposal (two words: space elevator), politicians will glut you with more money than you can eat.

In this case it is at least something that actually may work properly some day. Samsung presented a prototype NT-display back in 1999 and here's an more general article about NT-displays:

http://www.spectrum.ieee.org/WEBONLY/publicfeature /sep03/nano.html

There's a bunch of interesting papers out there on content-based image analysis and retrieval. Below is a sampling from my bibtex file. Does anyone else have others they'd like to share?

* Finding Naked People (Fleck et al, 1996)

* Video google: A text retrieval approach to object matching in videos (Sivic & Zisserman, 2003): web page demo here

* Names and Faces in the News (Berg et al, 2004)

* FACERET: An Interactive Face Retrieval System Based on Self-Organizing Maps (Ruiz-del-Solar et al, 2002)

* Costume: A New Feature for Automatic Video Content Indexing (Jaffre 2005)

A number of "quality" capacitor manufacturers have been having problems recently. There wasn't much Apple could do about it.

References:
http://www.geek.com/news/geeknews/2003Feb/bch20030 207018535.htm

http://home.earthlink.net/~doniteli/index27.htm

http://www.spectrum.ieee.org/WEBONLY/resource/feb0 3/ncap.html

http://www.spectrum.ieee.org/WEBONLY/resource/sep0 4/0904nfus.html

http://www.spectrum.ieee.org/techalert/dec04/ta121 504.html

Some people claim to be able to replicate the reaction 100% of the time now, based on carefully controlling the concentrations of deuterium in the water, with a steep dropoff in the energy generation as the concentration changes. Enough evidence of *something* exists to have gotten a DOE review, but the DOE essentially said it was keeping its hands off.

http://www.spectrum.ieee.org/WEBONLY/resource/sep0 4/0904nfus.html

http://www.spectrum.ieee.org/techalert/dec04/ta121 504.html

Some people claim to be able to replicate the reaction 100% of the time now, based on carefully controlling the concentrations of deuterium in the water, with a steep dropoff in the energy generation as the concentration changes. Enough evidence of *something* exists to have gotten a DOE review, but the DOE essentially said it was keeping its hands off.

Well, the last number of IEEE Spectrumcovers some new 3D projection devices. One of them consists of a sphere (much like a plasma ball) in which a translucent screen rotates (you know, revolves?) and several colored lasers project light into it.

Persistance of vision causes the eey to perceive a 3D image, much as you see the time floating in the air on those whacky clocks that have leds mounted on a rapidly moving arm, but in 3D

This is not to say, of course, that such a device would be sold at 250 bucks for a gaming system... but it's interesting anyway

Well, the last number of IEEE Spectrumcovers some new 3D projection devices. One of them consists of a sphere (much like a plasma ball) in which a translucent screen rotates (you know, revolves?) and several colored lasers project light into it.

Persistance of vision causes the eey to perceive a 3D image, much as you see the time floating in the air on those whacky clocks that have leds mounted on a rapidly moving arm, but in 3D

This is not to say, of course, that such a device would be sold at 250 bucks for a gaming system... but it's interesting anyway

You wanted the PC itself to be act as a firewire drive?

Good luck. Macs have this built into the firmware, not PCs. I don't think it's even on anyone's radar. But I don't imagine it's too difficult to write something that could do the job using libraw1394 and the SBP2 documentation.

Good luck!

So I looked up the relativistic Doppler effect and plugged in some numbers.

For a relative velocity of 400mph you get an observed frequency of 2.39999856GHz.

Now, looking at the 802.11b spec available at the 802 working group site I see that it operates in the 2.4 - 2.4835GHz range.

So the Doppler effect at 400mph introduces a difference in frequency equal to .0017% of the total frequency range. Unfortunately, I don't know what the tolerances for 802.11b are, but I have difficulty believing that .0017% would cause much trouble.

Now, backfiguring for a more common 5% tolerance, we get something like 500,000m/s or 1.1 million mph. So, yes, 802.11b probably won't work between passing spaceships. Aside from that, we're probably safe.

While I'm equally dubious about the parent post, you should know there was a burn before the PC+2 burn on Apollo 13, and it was done relatively soon after the explosion in order to get the spacecraft onto a free-return trajectory prior to pericynthion. Here's part of what I wrote about it in the original Spectrum article:

There was, of course, a fly in the ointment. During earlier Apollo missions, the outgoing trajectory of the spacecraft had been selected so that if the service module's main engine failed for any reason, the slingshot effect would aim the command and service module perfectly at Earth, a so-called free-return trajectory. But this trajectory put very tight constraints on the mission timeline, and for Apollo 13, it had been abandoned.

"We were on a non-free-return trajectory. If we did nothing, we'd whip back towards the Earth but miss it by several thousand miles," the Trench's Bostick explains. ...

"In 2 or 3 hours we were able to come up with a free-return maneuver. I think it made everybody feel a lot better--including the astronauts." Bostick remembers talking to the crew after the mission. "When we executed the free-return burn it made them feel that they might get out of this thing alive," he says.

While I'm sure they prayed, the crew was in fact trained for this: (from the original Spectrum article):

But Swigert and the rest of the crew powered up the Odyssey, seemingly effortlessly. "Therein lies the reason we chose test pilots" to be astronauts, says Kraft. "They were used to putting their lives on the line, used to making decisions, used to putting themselves in critical situations. You wanted people who would not panic under those circumstances. These three guys, having been test pilots, were the personification of that theory," explains Kraft.

Nor are the facts "highly classified". You can read them in excruciating detail here, and the air to ground audio is also available, as is quite a bit of the mission control loop audio.

They did get lucky, but as the saying goes "chance favors the prepared mind." The huge amount of preparation, skill and teamwork, onboard and on the ground, made the difference between success and failure: the gods help those who help themselves, after all.

Disclaimer: I'm the author of the Spectrum article

Unfortunately, as Jerry Bostick, the head of the Flight Dynamics branch notes in the Spectrum article, the bottleneck was that they didn't have the software in the Real Time Computer Complex (big bank of IBM mainframes) to compute the correct burn for the cojoined CSM and LM's trajectory using the LM's descent engine. The limiting issue for the Dynamics branch wasn't the trajectory options, it was executing them with the descent engine, without even the aid of the primary navigation system for later burns.

Disclaimer: I'm the author of the Spectrum article!

I'm not totally sure what you mean by Design document, I've seen many software shops. Some call the requirements document design, while others define the design document as the document that describes the high level description of the internal architecture of the system (system diagram, major modules, client/server decomposition, class diagram).

Either way, I like to start with some templates I created based on IEEE standards, a few come to mind, Here's the list:

IEEE standards pertaining to sofware engineering. In particular take a look at the Software Requirement Specifications and the software design descriptions.

Some of these are very documentation intensive, but I find that at least reading through them when starting a new project helps me direct my thoughts and make sure I don't forget anything that might be relevant to the phase in question (what? I need to think about the maintainability? the stability? the robustness?) pick and choose those things that apply to your project.