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Comment: Re:Then let us sue the government! (Score 1) 82

by Theaetetus (#49801941) Attached to: Supreme Court Rules In Favor of Patent Troll

That survey only looked at patents issued on a single day. There are still a couple hundred thousand unexamined patents from the 80s and 90s .. what will the patent term adjustment look like when they issue?

http://www.bloomberg.com/news/...

Nothing, because those patents don't get patent term adjustment. And while, yes, there are still a few patent applications floating around from that era, that law was changed 20 years ago. It's already been taken care of for everything since then, and since you can't apply it retroactively, there's nothing more that can be done.

Comment: Re:capacitance loss (Score 1) 544

by Mr Z (#49796711) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage

Capacitors store energy, they don't dissipate it. Likewise with inductors.

Transmission lines represent both capacitive and inductive loads simultaneously. The capacitance, inductance, resistance of the transmission line together combine to form the characteristic impedance of the line. (Ok, there's one additional term: the conductance of the dielectric between the conductors. But, for high voltage transmission lines that are widely separated, this term is effectively 0.)

The characteristic impedance of a transmission line is of primary importance for determining the ideal load impedance for the line. In an impedance matched system, the maximum power will be transmitted to the load with no reflections.

Reflections can cause a phase shift between voltage and current, making a transmission line effectively look reactive or inductive. (See surge impedance loading.) This can be corrected for in the same ways as reactive or inductive loads by adding capacitance or inductance elsewhere.

If the load itself is reactive or inductive then you can get reactive power transfer. Reactive vs. inductive is in some sense a matter of sign; in one, current leads voltage, in the other current lags voltage. In both cases, current is out of phase with voltage and that's the problem to be solved.

Reactive power doesn't transmit any actual power to the load, but it still sends current through the system. Current is subject to ohmic losses (thanks to our friend I*I*R). Sending current without delivering real power subjects you to losses without any benefits.

In general, the capacitance of the transmission line itself isn't the culprit on its own. Rather, if you have a reactive load (either capacitive or inductive), or you have imperfect impedance matching between the load and the transmission line, you can get current flowing through your wires that isn't driving a load. That excess current incurs plain ol' resistive losses.

There is one way high capacitance can cause real problems for transmission line management, though. The rate of propagation of waves through a conductor slows in proportion to the square root of the product of the inductance and the capacitance. So, for a highly capacitive line, reflections move slowly through the system, and it becomes more difficult to compensate for transients. That seems to be the real bugbear for buried high-capacitance lines. Again, you're not losing to the capacitance directly, but rather to the knock on effects that lead to poorly compensated reflections and reactive power transfer in the system.

(Dr. Jetton, if you're reading this... EE305 may have been 20 years ago for me, but I haven't completely forgotten it. And Dr. Schertz... I didn't completely forget my T-line theory either. I wouldn't be surprised if either of you would point out flaws in my summary above.)

Comment: Re:Ronnie Phone (Score 4, Insightful) 336

by Tablizer (#49795999) Attached to: FCC Proposes To Extend So-Called "Obamaphone" Program To Broadband

It's odd how it seems to politically matter who does something more than what is being done. Examples:

"GOOD" (or neutral) WHEN BUSH DID IT:

Corporate welfare
NSA
TSA
DHS
deficits
stimulus
bombing
medicare part D
golfing
hugging Saudi oilers
saluting with things in hand
feet on desk
subsidized cell-phones

"BAD" WHEN OBAMA DID IT:

Corporate welfare
NSA
TSA
DHS
deficits
stimulus
bombing
medicare part D
golfing
hugging Saudi oilers
saluting with things in hand
feet on desk
subsidized cell-phones

Comment: Really, Guys? (Score 4, Funny) 66

by Greyfox (#49795017) Attached to: Live Anthrax Shipped Accidentally To S Korea and US Labs
You'd think NOT GETTING ANTHRAX would be an effective incentive for your lab monkeys to follow the lab's safety protocols. Is it really THAT depressing a workplace environment?
"Hey Bob! Looks like we need to ship some anthrax to Korea."
"Ok! Did you make sure it wouldn't kill us before we start handling the samples."
"Does it really matter?"
"... No... I guess not..."

Comment: Re:Premature (Score 1) 544

by Mr Z (#49794997) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage

I used 5v as an example as the linked article spoke specifically of running 5V and 12V everywhere. I agree that you really want a higher voltage for distribution. 48V goes a long way, although it still requires quite a lot more copper than 110V or 240V for the same power carrying capacity. (About 5x if I did my math correctly.)

Now, if those in-wall adaptors could store some charge locally (small capacitor bank), and you didn't have to wire for peak current, only sustained current, maybe you could get away with smaller wiring that way. I'm skeptical.

Comment: Combo tech (Score 1) 221

by Tablizer (#49794909) Attached to: Why Detecting Drones Is a Tough Gig

What about a combination of image detection and echo-location? Image recognition and/or regular sound detection would identify candidate objects, and narrowly-focused echo location would then scrutinize the candidates further.

And so what if you take out a few birds accidentally? Just place a KFC nearby to handle such. They'll enjoy the free raw materials.

Comment: Re:Waste of Time & Money (Score 1) 261

there are also multitude of valuable scientific experiments that are done on ISS

The science-per-dollar in such ISS experiments has been very poor, considering the total cost of ISS and life-support and maintenance. 100 billion US dollars can buy a hell of a lot of R&D otherwise.

all the Moon missions brought back precious information about its geology. If we could make a self-sufficient base on the Moon and even send a single geologist there they will bring more data then all probes that we sent there to date.

I'm skeptical of that claim. One generally does not know what one is looking at until it's taken back to a lab. And robotic sniffers can do more preliminary analysis than an on-site human geologist per dollar. Robots (multi-spectral cameras) can "see more colors" in a sense. Human eyesight is limited. And we'd have more rocks/soil from more sites if we had sent robots under the same costs.

Comment: Technology Race, not Space Race (Score 1) 261

Our current gap is not really in space-specific technology. An "AI race" and/or 3D-printer/replicator-race would probably better serve the goal of living in space than a "space race" that only focuses on space-specific technology. We should focus on the bottlenecks, and those bottlenecks so far appear to NOT be space-specific.

Think of how difficult it would be to do space exploration in general without compact computers. Computer technology is not space-specific, but computer technology miniaturization happened to be a giant enabler of space exploration. Dumping tons of money into ONLY space-related stuff would not have been nearly as beneficial (being we've mostly plateaued on the mechanical and chem rocket side of things since the late 1950's.)

Similarly, AI and/or flexible manufacturing automation appear to be areas that help in other industries AND space exploration/colonization. Let's try to launch two birds with one rocket.

The ideal voice for radio may be defined as showing no substance, no sex, no owner, and a message of importance for every housewife. -- Harry V. Wade

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