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Comment The sewing needle (Score 1) 397

Including the 'needles' made of plant spines other sharp objects. Without this we wouldn't have been able to stitch pelts together to make clothing and clothing allowed us to live in nearly every environment.

My list also includes the knife. Early ones were made from stone, such as flint, by striking the flint with another stone shaping it into a hand held gadget with a cutting edge. It's the direct ancestor of my pocket knife. It provided a simple tool that was used to shape things such as pelts, branches, etc. Must be older than the needle.

Last, but definitely least, I'd say the fire kit which would consist of a stick of hardwood that could be made to rotate fast using the hands or a small bow onto a softer wood. Friction would create hot wood power that was used to start fires. Fire gave access to food which needed to be cooked such as roots and tubers and food which was better cooked such as meat. Our ancestors also used fire to manipulate their environment to their benefit.

Most of the gadgets in the article are not available to many or most of the earth's population but a cutting gadget, sewing gadget, and control of fire shaped provided for our species survival.

Comment How is the energy it absorbs dissipated? (Score 2) 176

The particles absorb photons over a wide band, violet through 'thermal'. Presumably the energy is dissipated as though from a black body unless it is removed by conduction. For example when illuminated by visible light they would radiate mostly in the infrared (unless the absorbed energy is removed by conduction) and would be seen to glow in infrared.

If they could be tweaked to absorb better at a wavelength that is best transmitted by human tissue and attached to an antibody that attaches to cancer cells they might be used as antennae to heat and destroy the cells.

Comment Was predicted in SF 20 years ago or so... (Score 1) 99

I remember that an SF story a couple of decades ago predicted that cruise missiles and the computer technology to direct their swarming would make them inexpensive weapons of choice for some nations. Looks as if that time is upon us.

"...officials note, having this capability will force adversaries to focus on UAV swarm response." I hope that we also have some focus onUAV swarm response; the 'swarm' of Kamikaze attacks on our fleet off Okinawa in WWII inflicted great damage even though we had AA shells with proximity fuzes, early warning radar, and fighter aircraft for interception.

Comment Re:Line Count is Misleading (Score 1) 23

I don't see that Mr | Ms | Mrs Coward's comment is pertinent. I sure don't want to need to code "y = z++" in assembly, much less binary, each time I need it. Computer languages are made up of symbols that translate to several to many lines of code and come with libraries of still more abstract code and the trend of higher abstraction appears to be continuing. It's good have routines coded once that that are used many times. Productivity increases.

Comment Re:A smart phone is rarely convenient (Score 1) 248

I agree with fff.

I suspect that the savings and utility will come with new construction where, for instance, the load carrying copper wires only go to the outlets or lights and the controls, which could control the light, socket, etc. could be wireless but their power would come a separate low voltage, low amperage, circuit this saving quite a bit of copper. The smartphone could control selected or all circuits but would not be the only control.

As an example thermostats control furnaces and air conditioners via low voltage, low amp, wires. New ones may also be controlled by a smartphone or computer.

It's probably not very cost efficient to convert existing homes in most cases.

BTW I get points when I mention that I can't go out as I need to update the firmware in my front door lock.

Comment Re:GPS on Mars (Score 1) 104

GPS is just a stand-in for the system they would use on Mars, which would be a much simplified version using existing satellites and the transport vehicle for the lander itself.

The atmosphere in Mars is fine for a quadcopter if designed correctly. How do you think the parachutes on NASA landers work?

I'm not sure what you mean by "simpler" system, what would it be? AFAIK it takes signals from 4 GPS satellites to get a fix, I think that it could be done with 3 having knowledge of the approximate position. That's with 3 or 4 satellites with GPS electronics in view at once. This implies that there need to be several more than 3 satellites in the constellation to be certain of having 3 or 4 in the correct position at any time. I don't think that the orbits of multi purpose satellites would be the ones needed for GPS.

Parachutes are used to slow the descent rate of the landers and are then cut away as the descent rate is still pretty high. Other methods need to be used to bring the lander to touchdown. I guess some engineers experienced in origami might be able to design a multiple rotor copter that would be compact in transit yet unfold properly once the parachute slows the descent rate etc, etc, etc.

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