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Comment: Re:It won't change. (Score 1) 233

by wierd_w (#49333575) Attached to: Hundreds Expelled, Many Arrested, For Cheating In India's School Exams

It's a little late to reply here, but I worked for a fortune 500 doing remote technical support for high end storage controllers.

A very alarming number of the people maintaining these controllers that were from India were quite simply not competent, and it did not matter if they were physically IN india at the time, or were working outside of india.

We are talking "You take control and do it for me now?" kind of incompetent. You know, the kind that dont know what the ls command does level of incompetency.

In stark contrast, the support personel from pretty much every other country knew what they were doing, and just needed a little assist with oddball quirks of their controllers, and did not expect our support staff to do their jobs, in addition to our own.

So you can take your "Oh, you must be a priviledged american!" attitude, and shove it. No-- this is very specific to Indian tech workers. An alarming number of the ones I interacted with should never have been hired.

Comment: Re:It won't change. (Score 5, Interesting) 233

No, CHEATING is a cultural thing there. Many feel they have the RIGHT to cheat.

Cheating on university exams produces inferior quality graduates, that only make the system cumbersome and unpleasant.

However, there are whole industries that capitalize on this phenomenon. H1B visa mills are just one such industry.

Crackdowns on Indian cheating will directly affect their financial bottom lines. Expect hard pushback.

Comment: Re:Unfortunately (Score 5, Insightful) 143

by wierd_w (#49307671) Attached to: Excess Time Indoors May Explain Rising Myopia Rates

But NOT going outside increases your risks of bone deformity from vitamin D deficiency, and now also increased incidence of myopia.

However, the REAL problem is that helicopter mummsy and daddsy are TERRIFIED that pedobear will rape little timmy and throw him away in an old icechest, because Fox News said so.

Comment: Re:Waste of time (Score 2) 252

Just to add to the above--

In addition to the 2-gang (Or 3-gang, if you want more room) conduit above holding the RPi or BBBlack, You can put another 1-gang box right next to/below/above it, and put a 6 port keystone cover on.

www.trianglecables.com/15-460-106-iv.html

You can get keystone inserts for a variety of cable types, including USB, RCA, HDMI, COAX, and pals. This lets you cleanly and aesthetically terminate cable connectors to the wall behind the TV.

www.trianglecables.com/cat5ecat6jacks.html

The rPi is powered by USB power, and needs a 2A power source for full draw (assuming you have lots of things hanging off the USB port). There's generic devices that can service this need quite robustly that can be embedded inside the housing receptical. A 3-gang enclosure gives another 2 inches on the long side, allowing for a powered USB hub in there. This hub can power the rPi, and provide some additional ports.

If you dont mind lots of junction boxes in the wall, Here's a perfectly workable arrangement.

Box 1: 3-Gang conduit with metal top. Houses the rPi, and has some room for any extras you want.

Box 2: 2-gang conduit with ivory keystone plate top. Houses a compact USB hub and a USB video capture device. (video for linux compliant) Cables are routed into this box from the rPi in the 3-gang box, and has keystones installed for HDMI out, RCA out, Stereo RCA audio out, RCA video in (capture device), stereo RCA audio in (capture device), ethernet, 3 USB, and one blank keystone modified with a momentary push button.

Box 3: Deep style 2-gang, metal top. Houses an AC power outlet turned sideways so the plug faces toward studs in the wall. USB power source installed in this box in the remainder of space, routed to the rPi conduit.

Inside box 1, we have a simple interrupter circuit fed from the USB power source (say, a 4 port USB charger, with 2 ports being tapped. The first one supplies the VCC and GND for the rPi, fed through a magnetic relay switch. The second supplies VCC and GND for the coil on the relay, with the pushbutton between. When the pushbutton is pressed, the coil kicks on, and opens the circuit power going to the pi. when the switch is released, the coil goes dark, and the relay slaps back into place, and the pi comes back on again.) along with the rPi itself, and a little room to ziptie extra cable length.

Box 2 has an unpowered 5 port USB mini hub, and a compact USB capture device crammed in it. It gets fed by a single 6in USB cable going through conduit to box 1. The HDMI, RCA out, stereo out, ethernet and reset signal cables are routed from box 1 to this box as well. very short (do they make 3in USB cables?) cables connect the USB capture device's RCA inputs and the remaining USB ports on the hub with the keystones in the cover plate.

Box 3 supplies 2 USB cables from the power source to Box 1.

A loadout with XBMC for raspberry Pi, a low profile wifi dongle, a low profile bluetooth dongle, and a low profile USB stick plugged into the wall, and a bluetooth remote, and you have an in-wall DVR/HTPC.

the arrangement I see on the keystone plate looks like this:

Column 1:
Reset
Ethernet
HDMI out

Column 2.
RCA video out
RCA audio left out
RCA audio right out

Column 3:
RCA video in
RCA audio left in
RCA audio right in

Column 4:
USB 1 (wifi dongle)
USB 2 (bluetooth dongle)
USB 3 (hdd stick)

Alternatively, instead of RCA video and audio out, and if the capture device allows, component video RCA inputs, RCA video input, and RCA audio input on columns 2 and 3.

I dont know of any compact video for linux capable capture devices that can grab raw component that are USB though.

Comment: Re:Waste of time (Score 3, Interesting) 252

by wierd_w (#49288723) Attached to: Ask Slashdot: Building a Home Media Center/Small Server In a Crawlspace?

Personally, I would just stick a beaglebone black, or an rPi inside a conduit junction enclosure, and install it into the wall that way as a utility box.

Image
You can get really fancy, and use a housing intended for circuit breakers instead, and get a fancy door that way. Marking and drilling some mini-ITX ground stud holes, one could install a pretty powerfu home media system into a wall that way, and have it reasonably serviceable/upgradable.

Personally though, I dont see the need for more than the small cube conduit junction linked above. A vanity wall panel can be installed on top of the drywall just below the box in the wall, with a button to reset the box, a USB interface, and an ethernet interface, routed out of the conduit. Hell, you could put the hdmi output on that panel too and have an in-wall home media server that way.

sealing it really good with silicone weather sealant, and installing it with lots of silica desicant packs (really, any good geek should have lots of these by now), coupled with the low power draw of these kinds of devices already-- It's a total slamdunk, IMO.

One could route a heatpipe exchanger through a small slit in the top of the conduit (rubber sheeting with slit, oval hole in conduit box, followed up with sealant.) and put a heatsink on the surface of the wall, if heat is a serious worry. I personally would put the conduit BELOW the insulation in the wall, (insulation is between the top of the box, and the drywall, leaving the back of the box in the uninsulated part of the wall) so that it has good exchange, and use the conduit box itself as a big honking heatsink.

Comment: Re: Know what's worse? Cleartext. (Score 1) 132

by wierd_w (#49279617) Attached to: Researchers Find Same RSA Encryption Key Used 28,000 Times

Sounds like WPAcrack.

You push out some reset packets at the targeted base station to get the connected peers to re-handshake. the toll gathers the handshake data, then uses a dictionary attack against the captured frames. It can take awhile if your dictionary is large.

if the passphrase is strong, it will survive very strong dictionaries. Otherwise, you can get the passphrase in minutes.

Comment: Re:Makes sense (Score 1) 239

by wierd_w (#49255077) Attached to: FAA Says Ad-Bearing YouTube Drone Videos Constitute "Commercial Use"

I have no illusions about this. There is nothing wrong with Youtube getting monetary reimbursment with advertisments on videos that dont have a legal mandate to not be for profit to exist. Kittens? Put all the ads you want.

Drones? Now you are getting into sticky waters.

Youtube can fingerprint if there is a tiny blurp of copyrighted music in the background. Surely they can find a way to fingerprint drone footage, and black list their ad injector appropriately.

Comment: Re:Makes sense (Score 4, Interesting) 239

by wierd_w (#49253965) Attached to: FAA Says Ad-Bearing YouTube Drone Videos Constitute "Commercial Use"

simply posting the video to youtube does not in and of itself, generate income.

Allowing youtube to monetize the video, and their subsequent royalty payment, DOES generate income.

The legal grey territory, would be with Youtube making money from videos (used to bring in users, who then view youtube only ads) of people's drone use. Youtube would then be generating income from private drine use, making it commercial, but not to the drone operators.

The proper remedy here, is to make youtube and other video sites not be able to collect income from uploaded videos of drone flight.

Not to penalize the drone operators, who simply want to share videos of drone flight with other enthusiasts, without a profit motive.

Comment: Re:This isn't an energy source (Score 1) 91

by wierd_w (#49247747) Attached to: Dry-Ice Heat Engines For Martian Colonists

Uhm-- YES. I know this. The energy comes from sunlight. I never suggested otherwise. That's why I stated that the power plant is at the equator, where insolation is greatest, and thus, harvestable energy is greatest.

Because there is significantly less energy at the poles, the atmosphere freezes into ice. The amount of energy needed to reconstitute this gas from the ice is significantly less than the energy needed to boil water, meaning you dont need the same intense energy sources.

Most of the energy in a steam powered plant goes right out the flu. This is because water has a very high specific heat. CO2 has a substantially lower specific heat. In addition, water has a very strong hydrogen bond that keeps the molecules close toghether that must be overcome to cause evaporation. This is not the case with CO2 ice. Significantly less of the energy would go out the flu in a well designed dry ice powered plant.

The ACTUAL QUESTION I asked, was if one could harvest enough thermal energy at the equator, to supply the power plant with more raw material to react with that thermal energy, to get useful mechanical energy.

Instead, you gave me a lesson in 101 physics that I already knew.

I am more intetested in leveraging the "Free" compression you get from the dry ice snow; Add just a little heat, and it expands voluminously. While still in ice form, significantly large quantities of CO2 can be harvested for very little energy, and then transported without much more than a pressure-friendly cargo container. The killer in gas compression based power systems is that you have to use energy to compress the gas. Not so in this case. The phase change does the compression for you. You just need to expend energy to pick it up and ship it. The energy used to convert it into gas, and thus get useful mechanical energy out of useless thermal energy, comes from sunlight.

The combined costs of harvesting and transporting the reactant are what need to be considered when evaluaiting efficiency curves for energy production.

Here, let me make this more appealing to you:

You can use a solar concentrator to heat up a tube filled with salt, which is attached to the hot side of a stirling engine. Mars' atmosphere is too thin to efficiently radiate heat away, so this alone is not going to be very efficient as a power generator. However, if you put the radiator side of the stirling engine into the dry ice sublimation chamber, and embed it into the dry ice (say, by dumping it on top), then there will be enough medium on the radiator side to have efficient thermal elimination. Suddenly the stirling engine works VERY efficiently.

At the same time, the dry ice is now getting the energy it needs to evaporate, and expand. You pipe it out through a turbine system, and get the resulting mechanical energy from the phase change. That mechanical energy can drive even more electical generators.

At no place in this process is energy magically appearing. It comes from sunlight, which is concentrated with mirrors.

The ACTUAL question-- was can you harvest ENOUGH energy, to overcome the logistical costs of harvesting the dry ice needed for the process to work, with sufficient excess to power a colony.

Comment: Re:Energy (Score 1) 91

by wierd_w (#49231703) Attached to: Dry-Ice Heat Engines For Martian Colonists

Mirrors are made out of aluminum metal, deposited onto glass, usually.

Silver mirror is made of silver metal deposited onto glass.

Both require exotic materials, as far as martian soil mineral is concerned. Polished steel plates have sufficient reflectivity, and could be manufactured cheaply on mars. They are also more resistant to being broken or blown around by martian wind/dust/sand storms.

Comment: Re:Energy (Score 1) 91

by wierd_w (#49231687) Attached to: Dry-Ice Heat Engines For Martian Colonists

Still have the costs of producing the solar panels, VS the costs of building turbines. Turbines are made of metal (Or even plastic, at these temps!), VS solar panels, which are made of refined, heavily processed rare earth metals and silicon.

Solar panels are very expensive, energy wise, to produce. They are also more fragile, and prone to breaking. The mirrors here could just be polished metal plates, and be very durable against sand/dust storms.

Computers can figure out all kinds of problems, except the things in the world that just don't add up.

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