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Huawei Successfully Tests New 802.11ax WiFi Standard At 10.53Gbps

Erich Re:Shannon (116 comments)

Aw, crap. That should read: Information capacity < frequency bandwidth * log2(1+SNR)

about 2 months ago
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Huawei Successfully Tests New 802.11ax WiFi Standard At 10.53Gbps

Erich Shannon (116 comments)

Information Capacity Frequency Bandwidth * log2(1+signal-to-noise ratio) "In the lab" typically means "BNC cables" which give you very high signal-to-noise ratios. And in MIMO you can potentially treat each pair of antennas a separate channel. You use fancy techniques to increase the SNR for each channel. The nice thing about the 5GHz spectrum is that the frequency band is pretty large up there, and not as much interference with other unlicensed things (phones, microwaves, other wireless communication users... though as it gets more popular that will change) as the lower bands. The not-so-nice thing about the higher frequencies is that they tend to attenuate rapidly when the signal is going through something thicker than air.

about 2 months ago
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SpaceX Wins Injunction Against Russian Rocket Purchases

Erich Calling them on the rhetoric (166 comments)

My understanding is that ULA gets paid lots and lots of money to maintain two independent launch vehicles, the Atlas V and the Delta IV. That way if one of the rockets is grounded for some reason, space access is still available.

ULA prefers Atlas V because it is more profitable for them. But it uses engines from Russia.

The Russian engines are purchased from a company with ties to one of the people targeted by US sanctions against Russia... so the judge has granted the injunction to prevent purchasing those Russian engines.

ULA has a stockpile of some Russian engines already, and they have the (less profitable for them) Delta IV if they can't launch Atlas V for any reason... and running out of engines would be one of those reasons. But ULA would prefer to continue buying engines. But we've been paying them to have both rockets available, so they'd better be able to show up with what they've promised.

Separate from this injunction, SpaceX is asking for a review of the large block by of ULA cores, as it was done just before (a few days before) one of the final milestones of SpaceX being qualified to launch for the air force. I think it's not unreasonable for them to say that it's unacceptable to do a huge purchase when if you wait for a few days you would have multiple vendors competing for the bid.

Even John McCain thinks that contract smells fishy: link

about 2 months ago
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Qualcomm Announces Next-Gen Snapdragon 808 and 810 SoCs

Erich Re:"There's zero benefit a consumer gets from that (47 comments)

So these cores with the arm V8 architecture add:

  • More registers (16->32)
  • DP SIMD
  • New instructions for crypto

and a handfull of other things. But all of the above aren't really benefits of 64 bitness, just the improvements to the architecture. The real benefit of a 64 bit architecture is the larger virtual address space... processes with >2-3 GB of memory. Every other improvement is usually just improvements that could have been added in 32-bit mode but they threw into 64 bit arch. Similar with x86-64.

about 4 months ago
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Ask Slashdot: What Do You Consider Elegant Code?

Erich Typically: terseness (373 comments)

Low-complication implementations of functionality are typically more elegant.

about 4 months ago
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The Myth of the Science and Engineering Shortage

Erich Glad to hear it! (392 comments)

Now come here and show us the stack of qualified, talented people for these open positions we have? Oh, wait, you're not actually trying to hire people? Maybe you mean there's no shortage of people writing crap on the Internet?

My total compensation as a qualified Engineer is similar to the average compensation for a doctor. I think that's reasonable. It's very hard to fill positions right now.

about 4 months ago
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Non-Coders As the Face of the Learn-to-Code Movements

Erich Because it's like Literacy. (158 comments)

Because being able to use logic to write instructions that are correct and unambiguous is a skill that everyone should learn. And basically that's what coding is.

It's like literacy or numeracy or basic understanding of science. You have a problem as a culture if it is culturally acceptable to say "I can't do math" or "I can't understand written language" or "I have no idea about the universe around me or how people go about understanding it" or "I can't read or write logical directions."

Do you expect everyone to be a best-selling novelist (or a writer that is enjoyed for all history?) No.

Do you expect everyone to be the next Ramanujan? No.

Do you expect everyone to be the next Knuth? No.

But it is expected that everyone have basic skills in these kinds of things. It's just necessary to understand the world. If you don't understand these kinds of things -- if you don't have basic skills in language or mathematics or logic -- then you are at a disadvantage in modern society.

I group computer science'logic here separate from Mathematics. Perhaps it shouldn't be. But having a population that doesn't understand things like this shuold be considered as problematic as a population that can not read and write.

about 6 months ago
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Who Is Liable When a Self-Driving Car Crashes?

Erich The driver is responsible. (937 comments)

If you are driving, you are responsible.

A car that drives itself is responsible for itself.

Who pays in the event of an accident is the driver. In this case, the car. Probably the manufacturer would be liable.

Manufacturers will probably get insurance for the car when driven autonomously. If self-driving cars are safer, this should be a lower insurance rate than you pay now. Additionally, self-driving cars will probably have sensor input that will prove/disprove fault.

about 7 months ago
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Intel's Haswell Chips Pushing Windows RT Into Oblivion

Erich Re:ARM computers (321 comments)

Woah. Woah. Woah. Woah. Woah.

I will let people crap all over a post that's basically regurgitating Intel Developer Forum drivel, and I'm certainly not going to say that WinRT has a future.

But I will NOT let you trash talk Alpha.

The Alpha was simply a much better processor than anything from Intel at the time. It was pretty much the fastest out there, though you might argue with some high end POWER or MIPS 10K or something.

Maybe you were running Windows and x86 programs on the Alpha? Those weren't blazing. But native Alpha programs were fast fast fast. And the architecture is clean and beautiful. Just beautiful.

So you can say that ARM has not much advantage over x86 today. That's probably true. You can say that ARM sucks, has too much complexity, and the system architecture is an abomination. That's probably true also. But you leave the Alpha out of your talk unless you know what the hell you're talking about.

about a year ago
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The Grasshopper Can Fly Sideways

Erich Re:Watching the video (127 comments)

Your "1ST rule of Rocket Engineering" can also be stated: You always develop sub-optimal rockets.

Seems like a stupid rule to me.

If an engine goes out, or there is some other problem, you need extra fuel to accomplish the mission (increased gravity drag). So you have some extra fuel and extra delta v, and that's a good thing.

But if those events are rare -- and, eventually, they should be -- then you often have extra fuel. If you can use that fuel to return the craft intact to reuse and make more money, then I think that's a damn good idea. If you must burn the extra fuel, then you will lose the stage. It will cost the company more, but "less profit" is maybe an OK choice.

The goal is to optimize cost while maintaining very high reliability. For very high reliability, you need to understand worst case behavior. For optimizing cost, you need to make the common case cost efficient. Having extra delta v for anomalies and using that delta v to lower launch cost (via reuse) when no problems arise seems like smart engineering to me.

about a year ago
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Ask Slashdot: Exploiting 'Engineering And ...' On a Resume?

Erich Do you have a CLEARANCE, Clarence? (207 comments)

You probably have a clearance. This is very valuable to many employers. Make sure you have that at the top of your resume.

Seriously, though, Clearance + EE is quite valuable. If you're worried about seeming "rusty" on the engineering side, get a MSEE from some university... a lot of very good universities have distance programs where you might be able to get started early.

about a year ago
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Will Donglegate Affect Your Decision To Attend PyCon?

Erich Proposal: Sensitivity Hats (759 comments)

There seem to be two groups of people here:

The first group of people is not offended by jokes, including jokes influenced by sexuality.

The second group of people is offended by jokes, especially jokes influenced by sexuality. A subset of this group is offended by such jokes when spoken by members of a certain gender. Of course, this is discriminatory so we will ignore that aspect and categorize them as offended in general.

I think there is a desire to be respectful of the second group while avoiding strict censorship of the [majority] first group.

I suggest a clearly visible sign that someone is offended by jokes influenced by sexuality (or, perhaps broadening this to include all jokes?). Perhaps a yellow hat or something like that. People within earshot of such people should refrain from telling such jokes. People wearing the sensitivity marker who hear things offensive to them can raise the issue to convention staff who will attempt to deal with the issue. People wearing the "sensitivity" marker who make such jokes will permanently lose the right to wear them.

People not wearing the sensitivity marker who hear something offensive to them should either (A) indicate to the offensive person directly that their conduct is perhaps inappropriate, or (B) move away from the offensive person so that they are no longer offended. If (A) is ineffective and (B) is ineffective or impossible the convention staff can be notified and they may or may not choose to act; anyone not wearing a sensitivity marker who is upset is free to go put on a sensitivity marker.

People may wish to have activities which may include things that people find offensive, they are free to ban sensitivity markers. Additionally, "sensitivity-marker free zones" or "automatic sensitivity marker" zones could be created. Or even entire conventions where no sensitivity markers are allowed -- one would expect a crude joke convention to probably not cater to overly sensitive people.

Of course, in an ideal world, everyone would be adult enough to know to watch their language a little bit, and to not overreact a lot. But given that certain people are especially sensitive for various reasons, we should find a way to allow them to coexist with the rest of society.

about a year ago
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Defcad.com Wants To Be the Google of 3D-Printable Guns

Erich Interesting intersection of Patent and Copyright (225 comments)

It's usually hard to copyright a "thing". If you make a thing -- a new type of shelving or gun or glass or pen or chair or whatever -- you can't get a copyright on it, you can maybe get a patent on it.

So for a CAD file of a gun, the CAD file could be copyrighted... but it would be copyrighted by the author, not by the manufacturer of the gun it was a clone of (unless they were the author, of course). Now, printing out the gun might be manufacturing something covered by patents... but copying the file wouldn't be creating the gun.

3D printing will sure be interesting from a legal standpoint, it potentially brings copyright and patent law together for just about everything. I would hope that we could establish that CAD files for 3D printers are equal to recipes for the purposes of copyright: a series of steps to create something. But that's certainly not what happened for source code.

about a year ago
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Form1 3D Printer and Kickstarter Get Sued For Patent Infringment

Erich Re:Submitter can't read? Wrong patent! (211 comments)

And IANAL, but it looks like the independent claims have a part that can be worked around; for example, copying or shifting data from one layer to the next.

about a year and a half ago
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Form1 3D Printer and Kickstarter Get Sued For Patent Infringment

Erich Submitter can't read? Wrong patent! (211 comments)

The complaint clearly states they are filing suit based on the 520 patent.

about a year and a half ago
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Intel CEO Paul Otellini Retiring

Erich Sanjay Jha for a replacement? (108 comments)

Sanjay Jha is out of MOT. He'd be my pick for a replacement. You heard it here first!

about a year and a half ago
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AMD Licenses 64-bit Processor Design From ARM

Erich Probably: they want to do both x86 and ARM? (213 comments)

What other company could make a processor that does both x86 and ARM? Windows 8 that runs both ARM and legacy x86 apps? I could see that as being pretty differentiated. Their GPUs are on par with nVidia, and they have better processor microarchitecture.

about 2 years ago
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FCC Chief: 300MHz More Spectrum By 2015

Erich C=B*log2(1+SNR): It's not just a good idea... (60 comments)

It's the law!

And you're getting very close to the Shannon limit with turbo codes. LTE isn't much more spectral efficient as compared to HSPA+, but it has wider frequency bands and so can get more peak speed to customers.

So you can increase the amount of spectrum you have, with the current infrastructure, to get more capacity. That will buy you a few years of network traffic increase.

But eventually you have to figure out how to get less capacity demand and more SNR. There's really only one way to do that: change the infrastructure topology. And that has lots of problems.

It's kind of like we're near "Peak Bandwidth".

about 2 years ago
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Slashdot Turns 15, What Are You Doing Later?

Erich Makes me feel old. (247 comments)

In a lot of ways, things are more or less the same. The SNR is lower, but that's true for the internet as a whole. :-(

about 2 years ago
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Patent Troll Sues X-Plane

Erich Ask Drew Curtis (214 comments)

Of fark.com. He recently had to defend against one of these patent trolls. His advice on a TED talk was (if I recall): fight the infringement, not the patent. His response with a lawyer was actually pretty cheap, and asked the plaintiff to circle the infringement and to disclose various things about the shell company. The other side doesn't want battle in court, either. Drew settled for nothing.

about 2 years ago

Submissions

Erich hasn't submitted any stories.

Journals

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First journal entry

Erich Erich writes  |  more than 12 years ago Hi, everyone. This is my first journal entry.

What was today like?

  • 6:15 awake
  • 7:15 arrive at work (4th real day on the job)
  • Write new parser
  • 12:30 Company pays for lunch at TGI Fridays for interns that are leaving
  • 14:10 switching parsing to flex causes 40% decrease in speed of the simulator. :-(
  • 16:00 Leave work
  • 16:20 Arrive at home, get steaks (12 london broils, about 40lb) out of fridge
  • 16:30 Leave for WCF for the new student cook out (I'm cooking).
  • 16:45 Commence cooking
  • 18:45 Dinner is served
  • 22:00 Two consecutive episodes of Law & Order
  • 00:12 trying new slashdot stuff before bed

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