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Comment Re:Shorting Amazon today (Score 1) 205

I think Amazon already has a logistics arm. The last mile will be handled by the local postal service unless the customer paid for better shipping.

To my house, Amazon shipments have been delivered by an Amazon employee in their own car for the past few months, sometimes the same day. For short distance delivery within a dense population when you have a lot of stuff to deliver, it's clearly cheaper to employ someone to deliver it than it is to use a postal service.

Comment Re: "only 2.7 billion years after the big bang" (Score 1) 98

Entropy only applies to closed systems, correct?

I sometimes wonder if our "universe" is actually a closed system.

No. The second law of thermodynamics applies to closed systems. If the system isn't closed, the entropy could go up or down. I don't know how you could consider the entire universe to not be closed. If it was open to more state, then that state by definition is part of the universe.

Comment Re: "only 2.7 billion years after the big bang" (Score 1) 98

That doesn't make sense. The universe is cooling down, hence the entropy of the universe is going down, not up. The moment just after the Big Bang had the highest entropy, and it has been decreasing since

Nope. Entropy in physics is the number of microstates the universe can be in. With all the energy concentrated in one place, there are fewer possible states. With the energy spread around, there are many more possible states.

Comment Re: "only 2.7 billion years after the big bang" (Score 2) 98

Meaningless. Spacetime expanded from it. Time is from it. The only source or cause of the big bang is that which is beyond space and time.
By definition.

Nope. There are plenty of models that take us from a low entropy to high entropy universe and back again within the same set of rules.

Comment Re: Seattle just closed the I-90 express lanes (Score 1) 245

My USA driving test was at around 2000. It involved driving around the block. The examiner said "Yep, you're good", signed the paper and I was done.
My USA motorbike test was about 2 years ago. It involved riding slowly around a series of cones in a school yard while the examiner looked on.

My UK driving test was 24 years ago. It was 30-45 minute of driving around, emergency stops, reversing around corners, 3-point turns and being observed all the time for good observation and signal use.

My UK motorbike was maybe 18 years ago. I rode in front of an examiner who was on his own bike and we shared a radio headset link through which he gave commands. We rode around town, did emergency stops, slow riding, fast riding, filtering (riding between lines of cars at the lights) and a bunch of other stuff.

   

Comment Re: Seattle just closed the I-90 express lanes (Score 1) 245

>Oh please, more fanciful crap.

I've passed the driving and motorbike test in the UK and USA. The USA test is a joke compared to the UK test. The USA motorbike test didn't even take place on the open road. It was just a trip around a school yard. The USA driving test was a drive around the block.

Comment Re:overkill (Score 1) 107

> Every instruction is 32 bits long, clogging one's instruction bandwidth.

ARM Cortex-M processors use 16-bit instructions (Thumb and Thumb-2). They've had a while to optimise the instruction set for embedded and SoC.

Yes. Thumb. A major mode switch to use a smaller instruction. I've integrated a few ARMs into chips (first the ARM7TMDI) and they were pretty much a nightmare to bring into line with normal OS practices. 15 years later, everyone seems to think this cranky instruction set and system model is normal, because it's what they grew up with. Yet the funky interrupt model, the funky mode switching, the lack of standard device discovery (that Linus Torvalds complained about) and bandwidth hungry instructions do not stand together as an example of a great CPU architecture, just a successful one.

The 68000 series didn't keep up, by it was an order of magnitude easier to work with. Especially the microcontroller variants. That stuff matters when you are building products. Atmel do some nice CPUs for the low end that are a pleasure to use.

ARM got their position lodged in our phones by being willing to sell their CPU core at a time in the early 90s when few others would. Back then we were crying out for a PC-on-a-chip, so we could develop a phone radio on a PC card run the software on the PC, then just port directly to the same machine on an ASIC with a PC+phone logic. But the answer was no. GSM back then was heavy lifting. No amount of money would get you access to that core on your ASIC. Meanwhile, ARM was there in Cambridge, ready and willing to take your cheque. If ARC had been a bit quicker, they would have been the incumbent. The ARC CPU certainly was much better (faster, easier, smaller) than the ARM at the time. They sold soft macros too, compared to ARM's hard macros with nightmarish memory bus timing.

Comment Re:80386 (Score 1) 107

They both count. My troubles installing Linux on an old VIA board stalled first at CMOV.
Finding a version of linux that was old enough to work on the CPU and new enough to boot from USB was a challenge.

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