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Comment Re:Class C (Score 1) 110

Based on the article it sounds a lot like envelope tracking:

The new advance is essentially a blazingly fast electronic gearbox. It chooses among different voltages that can be sent across the transistor, and selects the one that minimizes power consumption, and it does this as many as 20 million times per second. The company calls the technology asymmetric multilevel outphasing.

But looking back at one of their papers: http://www-mtl.mit.edu/~jldawson/Dawson_digest2009.pdf it is not exactly envelope tracking. They are starting out with an outphasing amplifier (dividing the signal into two constant amplitude variable phase signals which can then be amplified with an efficient nonlinear amp and recombined into the original signal) and then adding a discretely variable drain bias (much like an envelope tracker) but the purpose of the variable drain voltage is actually to minimize power dissipation in the combiner's isolation resistor. Thus they compare their efficiency and linearity only to outphasing types of amplifiers. I would be curious to see how this stacks up to pure envelope tracking amplifiers.

Comment Re:Consider a pencil (Score 1) 712

I used a Graph Gear 1000 for a while. It has incredible style points, feels solidly built, and the retracting tip is a nice feature for when you keep the pencil in a bag or pocket. However after around 6 months of regular use with storage in a backpack the springiness in the clip was lost, and due to the unusual tip-retracting mechanism this mean that the tip would not stay retracted. Also I found that I was not a big fan of the narrow and hard metal grip, the heavy weight during long use, and the narrow eraser.

Nowadays my preferred pencil is the Pentel "Quicker Clicker" series, specifically the .7mm model, PD347. The wide body with a thin layer of rubber on the grip (enough to soften without being squishy) is very comfortable for me, and the large and easily accessible eraser is very handy. The non-retracting tip means I don't like to carry it around in my pocket, but since I only use it at my desk(s) and it's much cheaper than the Graph Gear I simply bought enough to cover all of the places where I'll need one.

Comment Re:Actually, (Score 3, Informative) 74

Even showing the extension you are vulnerable.
Using the unicode character U+202e one can write from right to left and hide the real extension: for example the executable "SexyL[U+202e]gpj.exe" will be shown as "SexyLexe.jpg" by the filemanager!

On linux you can create such a file with
echo > $'SexyL\342\200\256gpj.exe'

Rather than simply modding you up I decided to try this out, and it works! Which is kind of creepy.

Comment Re:Flawed only if you redefine nutritious (Score 1) 305

Sorry, I did notice that section of the article but forgot to address it. Partly that's a bit of scientific he-said she-said that I don't have the expertise to evaluate, but the other part is I don't really trust the reporter.

The reporter has both shown a strong bias towards organics, and a willingness to bend facts (the tortured definition of nutritious) to unfairly attack the author's integrity. So I don't know if the Kirsten Brandt study was a good one, or if the excluded nutrients were important ones, or if there's any one of a dozen other reasons that those sentences could be misleading. The Standford study could be wrong, but this NY times article won't be the one to convince me, this reporter already lost my trust and I'm not going to take him at his word.

Since you dismiss the Newcastle University study only on the basis of Mark Bittman being a biased columnist (fair enough, he probably is), you may be interested to read the recent NY Times article which also explains some of the methodology differences between the studies which lead to different conclusions. In any case, I'm reserving judgement on both studies for now.

http://www.nytimes.com/2012/10/16/science/stanford-organic-food-study-and-vagaries-of-meta-analyses.html

Comment Re:The basics (Score 1) 208

Only for SMD production. I've done loads of SMD for 30 years now and especially for microwave RF work doing one off I think it would take a lot longer to CAD up a solder paste mask than to just hand solder it.

I think you'll find the cost of a PnP is having to buy everything in reels, and then having reels of unused stuff sit there. Yeah no headache with 0.1 uF decoupling caps, or if you focus all your work on one exact specific model of microcontroller chip, but everything else on the board is either buy a reel and throw most of it out, or do it by hand, and if you're doing 3/4 the board by hand, may as well do the whole thing and skip the PnP...

True, a pick and place requires a large scale of operation before it becomes worth the capital and the reels. But it shouldn't take much effort to create a solderpaste mask - whenever you're defining a new pad just add the solderpaste to the pad definition and you're done, all you need to do is export the layer at the end. This is helpful even for relatively small board runs - you stencil on paste, place parts manually, and reflow in a lab toaster oven / hot plate, etc. There's very little capital and once you get above a few boards or so (depending on the board and the assembly guy) it can be faster than hand soldering.

I imagine you could even use the inverse of the soldermask layer as a paste layer, at least for non-RF boards where everything except pads is usually covered in solderpaste. It's not ideal because then a bit of misalignment puts some paste on top of the soldermask which risks bridging for fine pitches, but I know there's CAM software out there which could shrink the solderpaste layer to correct for that.

Comment Re:To quote Triumph... (Score 1) 305

I agree. What if half of the football stadiums burned down from a serial arsonist. Almost the whole, freaking country would loose their minds. And I would be sitting comfortably telling them, "It's just a game. It doesn't matter and is not really important to life in general".

There's a huge difference! What you propose involves the actual loss of billions of dollars in property investment and a major impact on the sport in the US for some years due to loss of venues. What happened on WoW will require some overtime from the admin team to fix, resecure, and restore to pristine state from backups over a fairly short period of time.

So to better respond to the WoW hack: "Who cares, it's just an online game that they can restore from backups before you know it."

Comment Re:Flawed only if you redefine nutritious (Score 4, Insightful) 305

You missed some important points when you draw your conclusion:

That's a feature, not a bug. The role of a research paper isn't to make some broad sweeping conclusion, it's to carefully explore a narrow question, were the organics more nutritious, and on that question the answer was no.

This very important section of the article (emphasis mine) is conspicuously absent from your post:
Yet even within its narrow framework it appears the Stanford study was incorrect. Last year Kirsten Brandt, a researcher from Newcastle University, published a similar analysis of existing studies and wound up with the opposite result, concluding that organic foods are actually more nutritious. In combing through the Stanford study she’s not only noticed a critical error in properly identifying a class of nutrients, a spelling error indicative of biochemical incompetence (or at least an egregious oversight) that skewed one important result, but also that the researchers curiously excluded evaluating many nutrients that she found to be considerably higher in organic foods.

At this point that given that two research institutions have published metastudies with opposite conclusions, and that errors and oversights have been identified in the Stanford study, I'd have to say that the jury is out on this topic.

Comment Re:An even more economical way to store electricit (Score 1) 295

Taco Cowboy's link a few posts above addresses this and acknowledges the decreased energy density but made claims that large-scale supercaps would provide better economy in terms of $/(kWh*(number of cycles)). But of course $/kWh is also important because if they are highly capital intensive then they won't necessarily be attractive.

Comment Re:An even more economical way to store electricit (Score 2) 295

What is the $/kWh of industrial supercaps right now? The article you linked above had some projected numbers from startup companies, one of which seems to have gone under and the other of which is still in startup mode. I just helped put together an experimental off-grid PV system with 3kWh lead acid capacity at somewhere from $200-$250/kWh storage cost.

Is there anywhere a hobbyist or researcher could buy a few kWh of indsutrial supercaps?

Comment Re:Privatization Working? (Score 1) 77

Umm, this is how government funded R&D is supposed to work. The government spends money on projects that are too risky or too long-term for private companies to easily justify funding on internal dollars. Then when a higher level of technical maturity is reached private companies can take the body of knowledge, develop their own products for the government and private users, and start selling products to the government (and other customers) for less money than the government would have spent to build to develop and build it themselves (or pay a contractor to do for them). It's a win win win: the company wins, the government wins, and non-government customers win because they can now buy tech that up until then was controlled by the government.

It has happened in all sorts of fields including space. Government science and R&D funding has helped advance a huge number of fields.

But the government and many of the external researchers it funds are not in the business of making and selling products, so the plan for "technology transfer" and "transition" (to industry, whether real industry or the "prime" contractor industry) can be an important consideration in receiving govt dollars for a project depending on the work and technical readiness.

Comment Re:An amazingly big deal... (Score 1) 188

The world of manufacturing is faster and more flexible than ever because of cheap human labor in Chinese factory.

Need to have your factory assemble a new phone? You can train human employees in a day.

Maybe your supplier ran out of LCD screens, so you buy an order from another supplier but it comes loaded differently into a differently size box, or maybe it has a different connector. Time to call in your robot consultant to reprogram the purpose-built industrial bot so it can handle this new form factor. Oh wait, you have human labor? Just show him how to do it slightly differently and away you go.

If you had read the articles you would see that this robot is designed to be quickly configured to perform new tasks with a minimum of technical skills required. There will obviously still be a role for purpose-built bots that have better economy of scale, as that will be cheaper for extremely high quantity long production runs. A lot of manufacturing is meant to be fast and flexible with production or assembly lines being set up in days rather than weeks/months, maybe to handle the initial burst of demand as a new product is launched, then set up to produce a new product a month later. This robot is designed to enable US labor to compete with cheap Chinese labor in the world of fast and flexible manufacturing with less of a cost bump for the US product.

Comment Re:It happens again and again in nature (Score 2) 170

Even though oil does seep into the ocean naturally in some locations, human-caused oil spills are still bad news. Life will find a way, eventually, but in the meantime there is significant damage to the local ecosystem which was caused by humans, and resulting damage to human livelihoods. Even if you don't care about the ecological damage for its own sake do you not sympathize with the damage to human livelihoods?

To compare it to another scenario: floods sometimes happen naturally, but are sometimes caused by dams bursting, maybe due to human negligence. Does the fact that it can happen naturally make it okay if a burst dam destroys a town?

Comment Re:Oh good grief (Score 1) 285

Is it actually common for TA's to deliver lectures? At my school professors are not allowed to require their TAs to lecture - any professor who made a habit of it would find themselves in hot water from the labor union. Maybe it's different at other schools.

Sometimes grad students can teach courses as a lecturer but it's difficult to get approval for this, and it is a higher pay grade than TA because it's more work and skill. Introductory language courses are often taught by grad students, usually with one professor creating the lesson plan, teaching one class, and supervising a number of grad student instructors who teach the remaining classes in a given semester.

Comment Re:Teachers (Score 2) 110

Longest hours? Google: http://www.washingtonpost.com/blogs/answer-sheet/post/survey-teachers-work-53-hours-per-week-on-average/2012/03/16/gIQAqGxYGS_blog.html

53?!? And 6-8 weeks of PTO? WOW. Talk to any IT Developer, 50-100 hours per week. Average, easily 60. I was in Accounting & Auditing and averaged 55 hours (60+ for month, quarter, & annual closes). In IT, averaged 55; 100+ for deadlines. As an IT PM, 50-70 hours. 15-20 days PTO + 10 holidays.

And no, that does not count the hours spent on further education, certifications, and air travel for clients. And in the consulting world, not seeing home Monday to Thursday. Yes, our salaries are higher, 50k starting and growing to 80k+ over 5+ years, but considering the hours, I think comparable to teachers.

Just because you personally and possibly your industry are overworked doesn't mean you should belittle how hard teachers work. Why are you putting in so many hours anyway? In a school the (good) teachers put in extra time out of the love of teaching and their desire to see their students succeed and the teachers are overworked because there's not enough money to hire extra teachers.

Is IT really an important enough job to be putting in 100 hours per week? That's 14 hours/day 7 days/week during crunch time!! Are you at least getting OT or ST for those extra hours? You might be doing it out of love for your job but your manager and company are doing it because they love you putting in ~1.5 people's worth of work for 1 person's pay.

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