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Comment: Re:First 64bit (Score 1) 208

by wchin (#47897015) Attached to: Early iPhone 6 Benchmark Results Show Only Modest Gains For A8

Many make the wrong assumption that 64 bit processor means only increasing the memory pointers to 64 bit. This is not the case with the transition from the A6 to the A7. The instruction set changed from ARMv7s to ARMv8 (or ARM64). There are performance gains to be made moving to a new, revised ISA for which 64 bit is but one of the characteristics. Further, Apple has been working on their toolchain and they can leverage certain software compiler improvements especially within the Objective C runtime, like tagged pointers and inline reference counting that are made possible with 64 bit pointers.

See: https://www.mikeash.com/pyblog...

Comment: Coding vs. Degree is not Theory vs. Practice (Score 1) 546

by wchin (#47819497) Attached to: Does Learning To Code Outweigh a Degree In Computer Science?

Absolutely, to be a top notch software developer, learning to code trumps a CS degree. After all, you can get a degree but who knows how much attention you really paid in class. Further, learning to code goes beyond what is taught in a CS degree.

However, this isn't an issue of theory vs. practice. It's like saying, would you rather have a surgeon that learned surgery the traditional route with 4 year degree heavy in science, specifically biology classes and then went to med school, etc, or a self taught surgeon that learned at a field hospital during a war? Obviously, both would have to learn the basics of surgery itself, that is the actual cutting, the sewing, etc. The former is likely to have a far better grounding in a wider range of subjects to treat the patient, even if the a particular of the latter might be better at the actual cutting and sewing.

When one graduates with a CS degree, they might not have yet learned how to code, especially in a professional setting in a group. A coder can learn everything that a person with a CS degree learned, but that is basically going to each of the CS classes. Sometimes the hinderance to getting the degree isn't the CS classes, it's the other classes required for an undergraduate degree. In either case, to be a very good coder, you basically have to master both the theory and the practice.

Comment: Re:Nevada is the only candidate (Score 1) 172

by wchin (#47500319) Attached to: California In the Running For Tesla Gigafactory

Lithium is probably under 4% of the total mass of the battery. Tesla's battery is primarily composed of lithium, nickel, aluminum, cobalt, and graphite. Nickel and aluminum are the big constituents by mass of the battery. Total lithium mass per battery is probably around 20kg. For 1,000,000 cars, that's about 22,000 tons. That might be enough to start production in the U.S., but more likely, Canada will supply most of the initial amounts of raw materials including the nickel and lithium.

Comment: Poor password selection (Score 1) 59

by wchin (#47488571) Attached to: Tesla Model S Hacking Prize Claimed

This "hack" sounds like they brute forced a weak password on the service that that provides access to the Model S mobile apps. That password is shared with the "My Tesla" owner's website. It is possible to set that password to a far longer and complex password, certainly far longer than 6 characters. I suspect this contest was rigged and someone set the password to "111111" or something like that.

The car itself talks to Tesla using an OpenVPN session over 3G or Wifi.

Comment: Re:I've always thought that the best way for Israe (Score 2) 379

by wchin (#47442319) Attached to: A Skeptical View of Israel's Iron Dome Rocket Defense System

This reasoning, on the face of it, is absolutely ridiculous.

Because one side is very advanced militarily and the other side is not, then the side that is very advanced needs to let the other side have a fairer fight? No. Not at all.

A mugger comes at you with a knife. If you have a gun, that's not fair, you need to let the mugger with the knife stab you a few times before you pull the trigger?

Or let's say the other side has a stone, and is perfectly happy to hit you over the head repeatedly with it until you are dead. You have a M240 light machine gun. Very asymmetrical. You can take out the guy with the stone and a few of his buddies with a burst. But no! Unfair! They should be given machine guns too to make this fair. You should wait until they are given machine guns. Matter of fact, you can watch them get machine guns. So you wait to make sure they get all set up with their new donated machine guns, make sure they get the right training so that they know how to kill you with it, since it is only fair, right? No. If this were you, you would kill them if they are trying to kill you, no matter what weapons they possess, no matter how asymmetrical the military technology.

We are in very twisted times, as Hamas knows it can't really hurt Israel militarily with these tactics, but is very willing to provoke the situation such that they get pummeled. Each time Hamas provokes a pummeling, they get more funding and better weaponry from outside sources and more sympathy from both within and around the world. In the short term, Hamas has no hope of winning militarily. However, they hope that in the long term, they can grow strong enough to take on Israel militarily and wipe them out.

Comment: Re:Panasonic (Score 3, Interesting) 151

by wchin (#46688677) Attached to: Tesla: A Carmaker Or Grid-Storage Company?

At the cell level, Tesla is probably already paying under $250/kWh. Maybe even just under $200/kWh. That's below most lithium iron phosphate battery costs which are already competitive with lead acid batteries for total life cycle costs in an off-grid solar battery setup. So this "too expensive" comment is probably not right. Further, if they recycle battery cells from transportation use to grid storage use, then the costs could be far lower.

Comment: Re:If this was Apple... (Score 1) 258

by wchin (#45005079) Attached to: Samsung Fudging Benchmarks Again On Galaxy Note 3

I think you are lying. Sources?

Approximately the same way would be deliberately checking for a benchmark and artificially boosting performance to do well on that particular benchmark which is un-producable outside of that benchmark.

That is not the same thing as choosing benchmarks your product is good and and highlighting those benchmarks in your marketing material. That's just highlighting your strengths.

Comment: Re:Link Baiting This? (Score 1) 420

by wchin (#44775677) Attached to: Nokia Insider On Why It Failed and Why Apple Could Be Next

I have a Nokia 770 Internet Tablet. It was an interesting idea. Apple would never have shipped a product in that state of development. This was certainly not a marketing failure. It was a product creation failure. It wasn't usable - instead, it was a glimpse at something that might be interesting if they iterated on the software. At least when Microsoft ships utter crap 1.0, they usually follow up with not so crappy 2.0 and halfway decent 3.0. Nokia's follow ons were not so interesting in the primary area that mattered - the software. Same problem with the Sharp Zaurus.

Comment: Re:Perspective is important (Score 1) 351

by wchin (#44747951) Attached to: At Current Rates, Tesla Could Soon Suck Up Worldwide Supply of Li-Ion Cells

There is an issue for Tesla that a lot of the capacity you are mentioning is not applicable to solving Tesla's requirements. Between different chemistries and form factors, Tesla will require different plants to ramp up. We also don't know the battery specifics for anything beyond the Model S/X. However, Panasonic alone was expecting to make 600 million 18650 cells in the Suminoe Plant through phase 2. So Panasonic will probably be able to supply Telsa through 2017, but it's through 2020 that becomes the issue. Of course, that's a lot of time to ramp.

As for demand, there are almost 6 million households that have an annual income of $150k+ in the U.S. alone. So there is likely roughly 1 million of these households looking to buy a car in any particular year.

Comment: Perspective is important (Score 5, Informative) 351

by wchin (#44746275) Attached to: At Current Rates, Tesla Could Soon Suck Up Worldwide Supply of Li-Ion Cells

The lithium ion 18650 cylindrical cell production has been dropping as laptop demand has dropped and as laptops are moving to lithium polymer flat pack batteries.

Panasonic/Sanyo has had to close factories. Originally, Panasonic's plants that were acquired from Sanyo were supposed to be able to produce 300 million cells in their Suminoe plant in Osaka, Japan in just stage 1.

http://www.eetasia.com/ART_8800603184_765245_NT_5f784554.HTM

That plant alone, running at full stage 1 capacity could produce enough batteries for 40,000 85kWh Model S's. The demand from Tesla is strong enough that they are expanding production again:

http://articles.economictimes.indiatimes.com/2013-08-21/news/41433228_1_lithium-ion-batteries-production-line#

However, it really isn't the Model S or Model X that will have the issue, or even the initial production of whatever Gen 3 car that is coming. The big issue is making enough batteries for millions of EVs, and that will take some planning for the necessary expansion.

Comment: blending (Score 1) 413

by wchin (#43568925) Attached to: My most frequent OS migration path?

For my primary system:
UCSD P System -> DOS -> Windows -> OS/2 -> NeXTstep -> OPENSTEP -> Mac OS 8/9, Mac OS X Server -> Mac OS X

For servers:
OS/2 -> NeXTstep -> OPENSTEP -> Mac OS X Server/Linux/Windows/FreeBSD/Solaris

For virtualization:
VMware -> Parallels Server -> VirtualBox -> XenServer/VMware

For tablets/mobile:
Newton -> Palm -> Sharp Zaurus (Linux) -> Nokia 770 (Linux) -> Windows Mobile -> iOS/Android (mostly iOS)

Never did get BeOS/Haiku running for more than an hour to poke around, never did dabble with Amiga, C64, or Plan9.

Comment: Re:Tesla is nasty! (Score 1) 385

by wchin (#43079037) Attached to: Tesla Motors Loses Appeal Against BBC's Top Gear

That article has been completely debunked because of outlandish starting assumptions. The amount of metal they modeled for a car electric motor was orders of magnitude off. Even a brief scan of that study reveals just complete and utter incompetence that I wonder if it was a high school project.

As for electricity generation, the beauty is that the mix of energy sources for electricity generation can change over time. It can be oil, coal, natural gas, nuclear, geothermal, hydro, solar, biogas, tide, wind, or more. For a gasoline car, it's basically oil + a bit of ethanol for the entire lifespan of the car. Even as it stands, where coal and natural gas are the primary sources of fuel, electric vehicles have lower pollution levels and lower greenhouse gas emissions (mainly due to a shift to natural gas as the predominate producer). It also matter where the pollution occurs, and power plants are typically not downtown. Further, in the U.S., a larger percentage of the energy mix for electricity is domestically produced and not subject to the pricing whims of other governments that are not friendly to the U.S.

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