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Comment: technology resulting in lax behavior (Score 1) 304

by confused one (#48893703) Attached to: Government Recommends Cars With Smarter Brakes

background information: I own and personally drive both ends of the spectrum, a 2014 model car and a 1970 model year truck. The 2014 has all the available electronics features. The 1970... the only electronic device in that vehicle is the ignition module; and, that was an upgrade (I hate setting points). The 1970 truck doesn't even have power brakes. I'm not a luddite. Hell, I make a living as an engineer working for a company that designs and manufactures sensors; I'm not going to argue against technology.

To the point: I read this discussion and I listen to people talking about the active cruise control and collision avoidance systems in their cars and I come to an unfortunate conclusion... These systems can and do lead to people becoming less attentive while they drive. I totally get that these systems save lives. It's just that I see people becoming dependent on these systems and not using them as they are intended.

Comment: laser (Score 1) 151

by confused one (#48844523) Attached to: Being Pestered By Drones? Buy a Drone-Hunting Drone
You guys are going about this all wrong. Combine a targeting system with a decent laser and you can blind the camera and kill the drone at the same time. No need for dueling drones. Just make sure your system can tell the difference in a passenger aircraft or helicopter and a drone... It could go badly if you manage to punch holes in a police helicopter.

Comment: Can't get credit (Score 1) 314

by confused one (#48825243) Attached to: Radio Shack Reported To Be Ready for Bankruptcy Filing
Radio Shack already extended it's credit facilities well beyond what is normal. In addition, one of the major creditors has claimed Radio Shack management violated the terms of their contract. They operated at a severe loss during the Christmas season, which is usually their "good" time of year. There's no way anyone is going to extend Radio Shack more credit. Get ready for the fire sale, with all the creditors lining up to get back whatever they can to minimize the loss from their investment.

Comment: Re:Build your own fab (Score 2) 230

by confused one (#48749073) Attached to: AMD, Nvidia Reportedly Tripped Up On Process Shrinks
AMD had fabs. They had several. The cost of operating them was a heavy burden on their bottom line; so, they spun them off in 2009 (that would be Global Foundries) and decided to go fabless. Now, they're experiencing the consequence of being dependent on 3rd parties to do their manufacturing for them. TSMC is building more fab capacity -- they just can't get it online fast enough (it takes several years to build and qualify one of these fabs)

Comment: Re:Count down abort.. (Score 2) 70

by confused one (#48747573) Attached to: SpaceX Falcon 9 Launch and Historic Landing Aborted
Because that's when the problem occurs. Reasons might be as follows: First, while systems might have been exercised, nothing is fully pressurized, the engines are not running, the controls are all running through the link to ground, and everything is running on shore power. During the final moments, (not necessarily occurring in this order) they switch to internal batteries and disconnect from shore power, spin up the on-board computers with the launch parameters and hand control over to them, switch from ground (hardwire) linkage to radio communications linkage, engage range safety systems and get acknowledgement they're online, top off the fuel tanks, shut the fuelling valves, pressurize the tanks and pneumatics, spin up the hydraulic pumps, confirm the nozzle gimbals function correctly and finally start the engines. During any one of these steps (and I'm certain I've missed a couple) something can (and occasionally does) go wrong.

Comment: Re:Re usability (Score 1) 151

The vehicle is designed with engine out capability; so, if they lose one engine, it's not the end of the world. They put shields and baffles with Kevlar blankets between the engines so it's unlikely (but not entirely impossible) a catastrophic failure will harm an adjacent engine.

Comment: Re:well (Score 1) 272

by confused one (#48724877) Attached to: How Civilizations Can Spread Across a Galaxy
This is understated and under-represented in the discussion. If you wait for a star to pass through the Oort cloud, before you go exploring, you're waiting too long. The star will disturb objects in the Oort cloud, some of which will begin to slowly fall inward. Probability of a new extinction level meteor impact would go up considerably. from the article:

By some estimates, Gliese 710’s passing will cause as many as 2.4 million comets to move into Earth-crossing orbits. As noted in my book “Distant Wanderers,” these comets will only gradually arrive in our vicinity over a period of some two million years.

So, not an immediate threat; but, a threat non-the-less.

Comment: Re:What the hell is this guy smoking (Score 1) 235

by confused one (#48711039) Attached to: The Billionaires' Space Club

Generally I'm agreeing with you.

I think the reason you're not hearing them talk about recovering 2nd stages is their program of incremental improvements. Once they have a system for recovering the 1st stage working, and have successfully launched a couple of F9Heavy boosters, I think you'll see the 2nd stage recovery talks come back.

NASA didn't trust the "re-usability" of the Dragon enough to allow this (at the time) untested vehicle to be re-attached to the ISS. Assuming they get the contract for crew launch, that might change.

Comment: Re:What the hell is this guy smoking (Score 1) 235

by confused one (#48711011) Attached to: The Billionaires' Space Club

Because the booster might cost something like $20 million and the fuel cost is like $200,000 per launch. The fuel cost is 1% of the cost. If you can recover the booster and re-use it 10 times or more (without all the refurbishment required for each turn of the Space Shuttle), you've reduced launch cost considerably. If you can do this, it might make sense to just build a bigger re-usable booster, if you need to launch more mass.

SpaceX is doing this the right way: They want to test re-use; so, they increased the fuel capacity and upgraded the engines. There was no lose of up-mass, in fact it increased. Having done this, they still have the margin to bring the booster back. NASA never tried this for three reasons: (1) Every launch is basically a one-off, unique mission. Standardization was driven by Air Force and commercial interests. (2) Their budget is so tight that, if they could save a couple million on a given mission by using a throw away booster, they would. They put onerous flight rules in place, which guaranteed the cost of recertification of the vehicle for re-use made it uneconomical. (SpaceX is contractually obligated to use a new booster and new cargo/crew module for each ISS mission, even though they are theoretically re-usable -- they plan to re-use some of the components for commercial flights) (3)They convinced themselves it couldn't be done. They assumed the booster couldn't be controlled on re-entry -- it would tumble. They convinced themselves that firing an engine into a supersonic flow (engine pointed in the direction of travel, to slow the vehicle) would not be stable and would not allow for precision control of the vehicle.

We can predict everything, except the future.

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