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Comment Re:Not that many connections (Score 1) 92

I wrote up a little section on why wearable organic transistors are not well suited for any real digital computation to add on to your post (longer physical propagation delays, extremely slow FETs, high resistance interconnect, uneven/changing surrounding dielectric environment), but then I read the paper and realized that it's just the poor journalism at ExtremeTech that was talking up that angle. The actual researchers don't mention high power digital circuits like ExtremeTech, in fact the only application I saw that the paper directly mentioned was chemical and biological sensors.

The actual computing horsepower for wearable computers with any real complexity will obviously need to be provided by conventional CMOS chips for years to come. They are tiny and can be integrated in clothing with little impact and easily ruggedized for washing machines, they use far less battery power, they are reliable, and can actually provide real computing power. The place for integrated organic semiconductors in wearable computing is for things like displays and sensors which don't need high speed transistors but need large areas, flexibility, or interesting chemical properties. There is undoubtedly going be a place for very simple circuits directly implemented in organic textile based transistors, but it's not going to power a GPS receiver or anything fancy like that.

Comment Re:Queue the screams of hysteria (Score 1) 195

This is a well-known consideration when using bodies of water for cooling, and I'd be surprised if the environmental impact review for this project failed to do the calculations and address this issue. It's part of the discussion here. Some power plants even need to decrease their output power when outdoor temperatures rise in order to comply with regulations on how much heat they can dump into their sources of cooling water.

Comment Re:Simtec "Entropy Key" also does quantum RNG (Score 1) 326

It's actually not particularly difficult these days to create a compact and cheap boost converter, chips are available with everything included but the external inductor and coupling capacitors. Inductors can be large, but nowadays it's easy to find very compact SMT inductors. The efficiency may not be great due to higher resistance and core loss but it can be made quite cheaply and compactly.

Comment Re:Run it by a RF EE next time (Score 1) 177

Although the article claims to be talking about a silicon *transceiver* running at *300+GHz*, the graphics included in the article just have a planar horn antenna and a diode on an InP substrate all connected up to a SMA connector. A bit disappointing to be honest. No mention of whether they're using the diode as a detector or mixer (or both), but the pieces they are talking about appear to be a long ways away from an actual communication system.

One of the big problems faced in reality will be getting enough power to overcome the high losses at THz frequencies, particularly if they are eschewing LNA's and PA's at the front end and using the diodes for up-/down-conversion. Given the simplicity of the front-end it will require a lot more complexity and high-power in the back-end circuitry which they make no mention of solving. And if they are using some high-harmonic mixing with that diode then they're probably not going to meet regulatory emission requirements using just the antenna structure to filter out radiation of the spurious mixing products.

Comment Re:As a former TA I'm not surprised (Score 2) 333

I've never suspected students of cheating during exams, but I do notice it when grading homeworks and two students who turn in their homework assignment one after another have identical wrong answers, or answers identical to the solutions manual which any determined student can usually get.

Most of the time I did not take action when I suspected it, due the lack of complete certainty, the hassle you describe, and the fact that many professors did not encourage taking it seriously since the test scores were weighted more heavily anyway.

I did take action a couple of times. One time I was certain that a pair of students had copied from the solutions manual (it was a handwritten manual easily available as PDF online, both students had incorrectly transcribed a smudged section in a nonsensical way that made perfect sense if you had the solutions manual in front of you), so I gave them both zeros on the full assignment with a note not to copy from the solutions manual. Didn't hear a peep from either one when they collected their homework. The other time was a take home final where two students had liberally used each others' work (shoddy work I might add). When I let the prof know he just asked me to send a warning email (way to take action Prof. ______!) and so I did that and cut the two students' points in half.

Comment Re:Summary is moronic (Score 1) 593

This is anecdotal, but I have worked in defense contracting companies and there I was an "exempt" employee, meaning that I wouldn't get paid overtime if I go over 8 hours in a day, or 40 in a week though I was paid straight time if I worked late. I would take my lunch whenever I felt like it as nobody was checking on when or if I did. As I would set my own schedule within reason based on current projects and deadlines, I would sometimes end up working very long or short hours as necessary.

Then again I was working in R&D, it wouldn't surprise me if there are more specific rules for skilled manual labor as they probably don't want a welder working 12 hour days or skipping meals until he's tired and makes an expensive or dangerous mistake. Sometimes things like this can also a result of specific union rules.

My guess for a situation like welding on a nuclear submarine is that management and the military want to dot the i's and cross the t's as precisely as they can in terms of following laws and procedures so that if something does get screwed up on the sub or an employee gets injured they don't want anybody to be able to point a finger at the labor practices of management.

Comment Re:Why not work the other way... (Score 1) 38

This will never get funded, of course -- it isn't "big science" in any visible way

DARPA does love crazy game changing ideas like this... but you'll have a tough time getting this one past a technical review since you appear to be unaware of some serious technical issues.

Every cell phone tower is basically a big antenna.

It really isn't. A cell phone tower is a just a tower with many directional antennas on it. Typically antennas are installed in a trio each one covering 120 degrees, to separate the three "cells" the tower covers. Each antenna has its gain focused on the ground level where the customers are located. The gain straight up will be terrible. Because of this direction you'll be raising the noise temperature of the antenna dramatically because its picking up thermal noise from the hot ground, which will hurt your sensitivity quite a bit.

Then there are issues like sidelobe mitigation (which you can't do since the towers are fixed), radio interference (these are cell phone towers after all), actually getting the phase between multiple towers synchronized (not as easy as you think), the cost will be far higher than your student's guess (you'll need your own RF hardware, the cell phone receivers won't cut it), and the tower operators and antenna operators aren't going to be nearly as accommodating as you assume.

Of course, if this is true then I guess I'll soon have somebody knocking on my door for publishing this on /., but so be it.

I think you'll be fine :-)

Comment Re: Can't reduce the energy required, period. (Score 1) 156

You are correct, there is a definitive minimum energy required to split up a water molecule and get out hydrogen and oxygen. This energy is the same as the potential energy that would be released if you burned the two gases together in an exothermic reaction, getting the water back. Typically though electrolysis uses much more energy than that, because there is a certain "activation energy" threshold that you have to reach before the reaction can occur. Without a catalyst you have to put in extra energy to get over this barrier, and the extra energy left over at the end turns into heat. If splitting the water molecule is like pulling a weight a certain height up a hill (in terms of potential energy), the activation energy is an extra hump you have to pull the weight over, after which the weight is free to roll back down to the final height. See this illustrate here: activation energy plot.

So a catalyst does not let you get energy for free, but it lets you turn electrical energy into chemical energy of hydrogen and oxygen with less wasted energy.

Comment Re:Too Late (Score 4, Interesting) 235

You are jumping the gun quite a bit with your proclamation I think. Google+ is still a very new product, Google is doing fine as a company and will not dump this attempt because they got scared after less than 6 months of operation. Plenty of people, including myself, use it in addition to Facebook, and some people I know use it instead of Facebook. Maybe your social group doesn't use it, but that's their choice. It makes a lot of sense for Google to have a social media platform at their disposal as people spend so much time on social media sites, and they need eyeballs to sell ads. I have never been pissed off or suspicious about Google's intentions with Google+. So no, Google+ is not a failure and we won't be able to say it is for some time.

Side note: I don't understand why you think a Google+ failure would leak over into other services like Gmail. Gmail is still a very distinct service from Google+.

Comment Re:Again, on what basis an internet tax? (Score 1) 392

in terms of hard infrastructure, everything has already been paid for. There's no 'state-provided' street or sidewalk on which this business is taking place, nor a state-built thoroughfare upon which a consumer has to travel to visit a store. Yes, the US gov't invented the internet, but for at least the last dozen years every iota of bandwith on which our (consumer's) signals travel is paid for commercially, and the costs passed down to either we the consumers (through our ISPs) or the businesses (through their providers)

You are correct sir! The datacenters hosting the websites selling you products online are floating in the sky, not a building on a public road. Similarly, the warehouses from which these products are shipping and the offices housing the people who run and manage the company are floating in the sky. There are no trucks that ship the products to you on public roads because physicists have perfected teleportation, but are currently only licensing it to online retailers.

whatever actual physical location a business has somewhere, the services that they consume (fire, police, etc.) from the government are already paid for in their property taxes.

This appears to be an argument against all sales tax rather than merely against online sales taxes, by saying that everything can be paid for from property tax. One might argue that it would be a more regressive tax, because in a store (online or brick-and-mortar) selling luxury or high-end products the ratio of the value of the annual transactions to the value of the property would be much higher for luxury items. It would also make the progressive exceptions to sales tax on groceries that many (all?) states implement very complicated to lay out in the property tax code.

Self-evidently there's no need for police services for the sorts of store loss-prevention actions (shoplifters, etc) for internet stores.

Yes, no crime or theft ever took place in a shipping warehouse, or on the roads that shipments travel on, but brick-and-mortar stores are wretched hives of scum and villainy (/sarcasm). Maybe there are different levels of crime, but at most that would suggest a sales tax discount for online sales, not elimination.

In short, simply because the government needs money, and can take it, doesn't mean we need to tolerate it blithely like sheep.

In 22 of the 50 states (according to Wikipedia), internet sales are already taxed as a "use tax" but many people do not report it on their state tax return, essentially committing tax fraud. Having online retailers collect the tax is simply a more effective way of collecting an existing tax, at least in those 22 states.

To put the government's argument quite simply: The states and counties had a source of tax revenue with which to provide government services. Parts of this revenue were lost due to online shopping that goes untaxed. The level of services that the taxpayers want from the government is mostly unaffected. The choice is then to collect more taxes in some other way, cut government services, or go into debt. It's so easy to say that government is wasteful and spending should be cut, but it's incredibly hard to run an organization the size of the government efficiently and the government does do a lot of useful things for us that wouldn't happen without taxes.

Comment Re:Seriously? (Score 1) 160

The video you link appears to be a DIY stereolithography machine. These machines are very nice and create 3D parts with extremely high resolution. I have seen the output from one of these machines at a company I have worked out, the resolution is better than 100um and the parts that it produced needed no additional machining (in fact they were producing parts that could not have been produced in a single piece by machine). However the machine itself cost over $100k, and the resin costs $100's per liter. It makes a lot of sense for high end prototyping which needs extremely high resolution and where price is no object, but there is still a strong market for deposition style printers because the material cost is much lower. Resolution can still be quite high with the deposition style printers, the MakerBot is an entry level printer and professional users with more money to spend can get much better ones.

Comment NOTHING about this appears to be mandatory (Score 1) 241

If you actually read the announcement from Google and watch the short video you will see that this is not even available for the typical non-celebrity/-public figure users. Google is apparently working on making it available to all users, but nothing in the announcement suggests that this is more than a voluntary feature you can use if you want people adding you know that it's the real you and not somebody else. It seems like this would be a very useful feature indeed for public figure types.

There's no point in freaking out about this unless Google does make it mandatory. Even if it is made mandatory I'm not sure I'd freak out over it. I use my real name on Facebook and on Google Plus already, so my anonymity on these sites is not an issue. I prefer Google Plus over Facebook because (so far) I have much better control over my privacy, and this doesn't appear to be a privacy issue.

Comment Re:Omega FTW (Score 1) 505

This is a misconception. Your $5 Casio will be off by a tiny fraction; e.g. 1/2 a second per day. But, it will *always* be off by the same amount, so that the error will accumulate - it will be ~3 minutes off after a year.


So, a quality mechanical watch may vary forward and backward by more in a single day than the cheap Casio - but the errors will very often cancel themselves, so that after a year, the Omega may well keep much better time.

I see no reason why that would be correct, a good mechanical watch may keep better time than a bad quartz watch, but not for the reason you describe.

The basis of both systems is an imperfect oscillator which runs continuously at a certain resonant frequency and is divided or multiplied by the appropriate amount so that seconds/minutes/hours are the outputs. In a digital watch it is a quartz crystal oscillator, in a mechanical watch it is a balance wheel. Both will suffer from short term variations due to finite quality factor (Q factor) of the oscillator, and the digital watch will win due to the inherently enormous Q of a quartz oscillator versus a balance wheel.

The other big drivers of variation are temperature, mechanical perturbation (i.e. vibration and shock) and aging effects. Everything has a temperature dependence, though with enough effort compensation circuits can be built for quartz oscillators, and alloys with exceptionally low temperature coefficients of size and spring constant can be employed for mechanical oscillators. If the effort has been put in to design a very low temperature coefficient wristwatch, it might outperform a low-end digital watch despite the lower Q factor.

Note that pendulum clocks can have Q factors approaching that of a quartz oscillator, and that metrology grade pendulum clocks have been designed by NBS (now NIST) which are solidly in the realm of a quartz oscillator, though they are blown out of the water by a high quality crystal oscillator for much less cost.

Comment Re:Amazon also fiddles with search results (Score 1) 241

If people search for Armagedon do you think they want the directly matching misspelled song title (or whatever) or Armageddon the best selling movie?

There's endless cases like this, direct matching leads to worse user experience than trying to infer intent.

And yet the only case you listed was a ridiculous corner case. Chances are the GP's books' titles are not just single letter misspellings of highly well-known and popular books, and he probably should be the top result. I have definitely seen this with the Amazon results where I type in an exact title in the search box and the book I'm looking for is several results down, below both related and unrelated titles.

Comment Re:Calling BS on PAID post-secondary training (Score 1) 427

You are missing my point, which is that internship is the same as apprenticeship and it should be viewed as an alternative to formal education.

Internships and apprenticeships are not the same, with the former referring more to white collar job and the latter referring more to blue collar and typically having a more formal training aspect to it. Though I admit the two are similar. Nevertheless your example is poorly chosen as apprentices (at least in the US) are typically paid, because again they are working and providing value to an employer.

So if I am getting an intern, I am getting a known quantity: somebody without prior experience, and so I am absolutely not going to pay them anything or I may pay them a token amount, something definitely lower than minimum wage.

News flash: you never get a known quantity when you hire somebody. As an employer you have chosen to take on certain risks in return for the rewards of being in management or ownership of a company. If you aren't willing to take on the risk of paying somebody without credentials then that's fine, but you're wasting their time if you ask them to work for you for free.

At my very first internship where I was paid quite nicely my first two weeks or so consisted largely of handing me some textbooks and papers on the subject I would be working on, telling me to teach myself to program in Matlab, and asking me to ask questions if I got stuck. I was paid for my time to train myself of course, because hiring somebody who already knew how to do what I ended up doing for them would have cost my employer even more.

Now, what is actually funny, is that in USA an intern can work for a company for free, but should he be hired for actual money, then he must be making minimum wage.

I don't find it funny at all that a company can legally get interns to work for free, but certain federal and state exemptions do exist which allow this to happen under specific conditions, such as receiving college course credit. Do you remember your history classes where companies would hire people and pay them such utter crap that they were practically starving in the street while working full time or more? Actually that's current events in some countries... If legal exemptions were created which allowed interns to be paid less than minimum wage then all of a sudden lots of jobs would stop being jobs and would become internships methinks, and that's not good for society.

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