…ruined by technology. These are pretty funny.
Category Archives: Technology and Society
Comparing Software Installation
Between Linux and Windows. Well, it’s no surprise — we always knew that one was much more difficult than the other.
Reforming ITAR
Will North Korea’s latest shenanigans set back the effort?
Space Solar Powerballs
Trevor Brown proposes spherical solar power satellites.
This isn’t a new idea. I wrote a paper on it back in the early nineties for an SPS conference, and I think that Geoff Landis has done some work on it as well (for instance, here’s a report of a talk that he gave on it at the 1996 ISDC, which was the last one that I attended prior to by going to Dallas two years ago — ctrl-F for “spherical”). It does vastly simplify the design issues, because it is no longer necessary to point the panels at the sun. One of the comments there needs some elaboration:
While the surface area of the sphere facing the Sun matches your calculations, the whole side would not be available for power generation. The so-called Beta angle, or the Sun angle, affects the total amount of power converted. Also, while a sphere would not need rigid station-keeping and attitude control to collect solar energy, the transmitter back to Earth certainly will. Also, a large spherical structure would be more taxing on a station-keeping/attitude control system than a more planar design. These caveats in mind, this is a creative alternative.
With regard to the needed area, the beta-angle effect means that at any orientation, you’re only getting the effective solar panel area of the cross-section of the sphere. That is, while the hemisphere has twice the area of the circular cross section, the non-zero beta angle of all points except that at the center of the illuminated area means that you need twice the solar panel that would be necessary if it were a flat circle. Add to this the fact that you have just as much area on the side in shadow, and it means that you need four times the total solar panel area to get the equivalent collection capacity of a pointed flat plate. So you have to postulate very cheap panels for this to make economic sense. But if you can get them, the simplification of the design is worth a lot.
As for pointing the transmitter, that’s actually not so tough a job. You hang it down below the sphere, and it will remain vertical, due to gravity gradient restoring torques. You could point it with control cables all around its circumference, attached to the sphere. In addition to inflating it, I also considered putting a charge on its surface to keep it spherical, but it would take a lot of ions, particularly for a big one, and inflating is probably a better solution, though subject to leaks, and the need for gas resupply.
One other point. I actually considered a fleet of them in MEO, continuously switching from one rectenna to the next as they orbit, to reduce the size of the transmitter antenna, which gets kind of humungous out at GEO.
Danger: Sand
Some thoughts on the uselessness of MSDSs.
Of course, it’s not as hazardous as this toxic substance.
Fusion News
There’s an interesting question at the end of the post about the progress of ITER versus polywell:
Why hasn’t Polywell Fusion been fully funded by the Obama administration?
I suspect it’s not “green” enough. And by that, I don’t mean that it has too high a carbon footprint — it obviously has none. No, the problem is that it doesn’t force us to tighten up the hair shirts, and force us to live the politically correct lifestyles that our betters demand of us.
Really Great Stem Cell News
I hope that this works out, because it doesn’t look like we’re getting off the planet any time soon, and I’d still like to see that happen while I’m on the upper side of the turf:
Researchers at Harvard and Advanced Cell Technology are reporting that they have been able to turn ordinary skin cells into stem cells by dousing them with the proteins made by four specific genes. The researchers were then able to turn the stem cells into mature cells of various tissues.
Faster, please. And note, no embryos were destroyed in the making of this research.
A Thought From Lileks
“Once again I say: any planet whose ecosystem can be wrecked by burping sheep deserves it. Darwin on a galactic scale. Man up, Mother Earth.”
[Late afternoon update]
Here’s the correct link, for those who were scratching their heads.
Nirvana
I have found a rare confluence at this conference — simultaneous power and connectivity. I hadn’t realized until today just how much my laptop battery sucks (HP Pavilion dv5, less than a year old, if anyone’s wondering). I started using it this morning, and checked the battery after about fifteen minutes, and it told me I had about fifty minutes left…
I don’t know if it’s the design, or if there’s a memory problem because I don’t use it off the grid much, and rarely deplete it, or what. But I might have to start carrying a spare, or get one of those things that plugs in externally as a backup.
And of course, I don’t have the ultimate, unachievable combination — power, connectivity, at a comfortable table, with something interesting to listen to. I’m sitting in a chair in the hotel lobby. Fortunately, there’s nothing I’m really hot to hear going on right now.
Immersive Simulation
Tami Griffith of the Army Simulation Tech and Training Center is describing the use of current technology for training. Shows a video of interfacing a Wii and balance board with Second Life. Apparently a lot of people are hacking the Wii for things like this. She says that whole-body training is much more effective and memorable than joysticks or cockpit simulators.
Cool.