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Comment: No end-user would do this fiscally (Score 1) 226

by gavron (#49347035) Attached to: Russian Official Proposes Road That Could Connect London To NYC

Pretend you wanted to drive 8000 miles. The IRS expects that the cost per mile allowance is $0.50 based on gas, oil, tires, vehicle depreciation.

To drive those 8000 miles the apportioned cost would be $4,000. You can get 10 round-trip tickets London-NY off-season and 5 on-season for that.

During your trip if you follow your manufacturer's recommendations you'd need to change your oil three times. So would everyone else. At equal intervals. What a pile up at the mechanic at 3000m, 6000m, and just past it. Yuck!

If you have average street tires then the trip there and back would kill half your tires (so they only have half left on them you need to replace them on this trip).

If the speed limit was set at 100MPH and there were no stops you'd actually maintain that, but given that you will stop to stretch your legs, etc. that average goes down to about 80. That's 100 hours of driving, which with two drivers and sleeping in the car is 5 solid days. What's the value of 10-man-days lost?

Finally even if all those things were true, the largest cargo that could be transported is a triple-tractor trailer -- 3 containers. This ship can do 18,400 http://en.wikipedia.org/wiki/M.... You'd need 6,133 trucks to equal that and it would take them 5 days. The cargo ship can make it in 3-4.

This is a nonstarter from every possible fiscal angle for the end-users, even if the road magically arrived today.*

E
* note that I didn't address at all that by the time your European car reached the US, it would not be homologated for street use by the DOT so you'd need to rent a car here anyway, and vice versa.

Comment: Article is wrong. Transceivers do this already. (Score 4, Interesting) 47

The article is misleading. Transmission and reception on the same "frequency" is done today. However, there's some other "discriminator" in the signal. Either modulation method, phase, shift, orientation, or "something" is different so that the receive and transmit don't collide.

This article -- despite its misleading introduction -- talks about a limited application whereby RX and TX can occur using the same frequency *BAND* (they say "spread spectrum") and allow full-duplex communication. The advance is that this is all on one chip.

What would be truly revolutionary, like the example of two people talking to each other at the same time, is the ability to transmit and receive using the *same* exact method by both transceivers. THAT would be the holy grail.

Not there yet.

E

Comment: Re:Transfer the heat to.... where? (Score 1) 51

by gavron (#49265759) Attached to: Fujitsu Could Help Smartphone Chips Run Cooler

It depends what you mean by "by design" is :)

Air is a great insulator, but poor conductor of heat.

My familiarity is with generatios of Dell laptops that exchange more heat through the bottom of the case they do they through venting to the air. Their support system even ensures you tell them if you're using your laptop "on a solid hard surface".

FYI 100C is higher than most hardware's failure point.

I know you want links. I'm off to bed. Google is that way --> Lazy is that way ---, and links are found in delis.

E

Comment: Transfer the heat to.... where? (Score 1) 51

by gavron (#49265525) Attached to: Fujitsu Could Help Smartphone Chips Run Cooler

In a laptop, the use of similar devices makes sense, as the heat can be transferred
somewhere where it can be dissipated into the air. Unfortunately it's more efficient
to transfer it to the table you have it on, so the bottom gets the heatsink which
makes it horrible to actually put your laptop on your lap-top.

In a smartphone, it's being held in your hand (on the back) and up to your face (on
the front) with fingers on the sides. Where to exactly are they going to move the
heat??? Heat exchanging is nothing new, but the ability to remove heat requires
the device interact with a cooler medium to transfer that heat. Normally that's
your palm, or the air, or both.

So... I ask again... transfer the heat to where?

E

Comment: Re:No more downtime (Score 5, Informative) 117

by gavron (#49043493) Attached to: Live Patching Now Available For Linux

Ok, so here's the simple answer. Note: I'm generalizing a lot to make this simple.

All functions have a known entry point which you can think of a name that you can call like
print("hello world"); -- calls "print" so it knows where "print" is.

Somewhere in the memory was loaded the function print(). There's also a symbol which allows everyone who wants to call print() to know where it is.

The livepatch loads a new function into memory. Let's call it print2(). It then goes over and makes the symbol that used to let everyone know where print() is point to print2(). Anyone that comes after this patch will still think they are calling print() but in fact will be calling print().

The stop_machine() is part of how ksplice (the proprietary-vendor method does it). That is not part of kernel live patch (klp).

What klp does is ensure that a process is in a "good point" to be messed with, and then changes its pointer to e.g. print().

That allows no changes to affect the process until that pointer to print() is changed at which point any subsequent call to print() will run print() instead.

Ehud
P.S. I have some code from the early 1990s where we used to do this on VMS/OpenVMS. We literally patched the running kernel (much as is done here) and allowed a system to run for years with newer kernel code.

Comment: Seiki +2 (Score 4, Informative) 330

by gavron (#49039965) Attached to: Ask Slashdot: Affordable Large HD/UHD/4K "Stupid" Screens?

I also second the Seiki 39". Got mine from Amazon.com when it was $400. Now it's 2/3 of that.

On my NUC it actually uses the 4K resolution but I rarely use it as a monitor because of the low refresh rate (15Hz) at that resolution.

It is an AWESOME TV!!! I have it hooked up to
- Roku3
- Google Chromecast
- Amazon Fire Stick

If I had to find downsides it would be
- no "discrete code" to switch to a particular input. One selects "source" then scrolls up or down from the current source to the eventual source input. This makes things tougher for scene-remotes.

Ehud

Comment: 68th to 22nd and there are many to go (Score 5, Insightful) 192

by gavron (#48985495) Attached to: JavaScript, PHP Top Most Popular Languages, With Apple's Swift Rising Fast

All new languages start out at the bottom, as Swift did.
In time, the ones that don't get used fall down.

Swift has gotten up to 22nd, but the rest of the climb past the stragglers won't ever happen.

However, to be "the most popular language" is clearly no contest worth winning.
Paris Hilton and Kim Kardashian are most popular compared to Steven Hawking and Isaac Asimov.
Being popular doesn't mean better, useful, or even of any value whatsoever. It just means
someone has a better marketing-of-crap department.

There's a time to have popularity contests. It's called high school.

E

Comment: Nobody should trust these scammers (Score 5, Insightful) 80

by gavron (#48893611) Attached to: Winklevoss Twins Plan Regulated Bitcoin Exchange

Who would trust them?

First this: http://www.sec.gov/Archives/ed...
(bitcoin trust)

Then this: http://www.investopedia.com/ar...
(bitcoin payment system)

Now this thing... ("regulated" exchange that can't leave the US for an international virtual decentralized currency...)

Perhaps they just didn't get that memo about their relevance having tanked somewhere after they wanted to
renege on their FB settlement and go for a do-over uh-gain:
http://www.bloomberg.com/news/...

Their fifteen minutes of fame is up. The harder they try and bring themselves
into relevance the funnier it gets. The bell has rung. Time to get off the stage little boys.

E

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