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Linux Needs Resource Management For Complex Workloads

EETech1 Re:From the "is it 2005? department" (160 comments)

IBM has DIMMs with flash memory already.

3 days ago

Industrial Control System Firms In Dragonfly Attack Identified

EETech1 Re:Against man's stupidity... (24 comments)

I use the eWon, and MBConnect devices all the time, one or the other goes in to every machine we build. They are VPN gateways with secure login so we can remotely work on a machine instead of having to immediately travel to it to check the slightest thing.

None of our customers leave the internet side of the device plugged in. Unless we are on the phone with them, and they are by the machine, it is unplugged. As an additional level of security, the device has a keyswitch connected to it that must be turned on to allow it to connect to the internet, just in case it gets plugged in.

Most devices are managed through the respective manufacturers applications via the cloud, so we just have to download their application, and log in, and it handles getting the keys, and establishing the secure VPN tunnel. It is possible to manage your own infrastructure, but I don't know of anyone who is large enough, or chooses to do it.

I put the eWon app on my brand new work PC, now I have to check if I got pwned the first day got my new Lappy:( The remote access apps are one of the few things that does not get installed on the VM. Connecting to the VPN, through the VM can really be a pain!

The MBConnect devices are really cool, they can even verify the entire system, and reload anything that does not match what is stored inside itself. Besides providing a huge obstacle for anyone wanting to Stuxnet the system, they allow a customer to replace a PLC with a spare, reboot, and have everything come back to normal, and they allow for easier updating of a whole system by passing the program to the MBConnect device, and having it apply the update locally.

Nothing more scary than flashing a PLC remotely, and rebooting it. If it doesn't come back online, you might have to take your Lappy, and leave on an immediate road trip!

about two weeks ago

Bug In Fire TV Screensaver Tears Through 250 GB Data Cap

EETech1 Re:It's 2014 (349 comments)

My Bittorrent client can do that:)

about three weeks ago

The Rise and Fall of the Cheat Code

EETech1 Hey! (178 comments)

Dangit... You just made me jump to my bootloader...

about a month ago

$500k "Energy-Harvesting" Kickstarter Scam Unfolding Right Now

EETech1 Upgrade To PRO!!! (448 comments)

You definitely need to get yourself on the waiting list for the upgraded PRO version with the quantum solvers then...

Perfect for exactly these chicken and egg type problems, where both sides are seemingly full of shit simultaneously!

(and the upgraded blue LEDs are friggin' awesome)

about a month ago

Kingston and PNY Caught Bait-and-Switching Cheaper Components After Good Reviews

EETech1 Re:This is fraud. (289 comments)

Many things can happen when going into production. Perhaps they always intended to go into production with the cheaper controller, but they had a problem with the firmware they were struggling with, and so they used a more expensive controller that was a slam dunk to buy themselves more time to perfect the cheaper controller, and not miss their target delivery dates.

about a month ago

EU, South Korea Collaborate On Superfast 5G Standards

EETech1 It won't matter anyway (78 comments)

I have 4G now, and it is still as slow as 3G, which is as slow as 2G, which is as slow as 1Xrtt when everyone is using their phones and the pipe to the tower is full. I often see 10 - 30 Kbps during peak times.

During the middle of the night, 1 bar will get me 1.3 - 1.9Mbps on 3G, and 3 - 5 Mbps on 4G, but during the day, I struggle to get 100Kbps on 3G or 4G, even with 5 bars.

I can watch my download speed increase as everyone goes to bed. It's funny (sad) to graph my download speed and see it jump up on the hour, and jump a little less on the half hour as the pipe opens up.


about a month ago

30-Day Status Update On LibreSSL

EETech1 Re: Throwing out all compatibility hooks makes it (164 comments)

Everyone who can, will jump ship to Theo's version ASAP. Being strong enough to demand the best, and accept nothing less is a good thing when it comes to software security.

Many of these libraries are essential, and mostly taken for granted.

How many people thought that it was already an OpenBSD project, and had Theo's scrutiny already?

There are some true leaders within the OSS world, and we are lucky to enjoy what is made of their efforts. As the TLAs become increasingly invasive in our daily lives, having well written clearly documented textbook code is the only thing you can count on to provide any level of security.

Version 4.0 of Linux will be the same way. Linus will take his kernel, and go where things are sane again, and there will be no compromises. Take it or leave it. This is how things are done. Correctness is the law of the land.

Or you will be taken of your privacy, and computer security at every possible turn.

about 2 months ago

Free Can Make You Bleed: the Underresourced Open Source

EETech1 Re:Cheap ass gits. (175 comments)

Because of Minix.

about 3 months ago

Why Tesla Really Needs a Gigafactory

EETech1 Re:What size does one take? (193 comments)

I worked on a hybrid demo that used 14,400 of them.

25 of them connected in parallel.
(3.7V @ 75Ah)

12 groups of the 25 in series.
(44.4V @ 75Ah)

16 of the 25 X 12 sets in series.
(710V @ 75Ah)

3 of the 16 X 25 X 12 sets in parallel.
(710V @ 225Ah)

Very scary to work with, especially in the bilge of a boat!

We went way overboard with the charge monitoring, but when we had cells fail while we were testing, they could be easily identified, and swapped out, then the rest of the pack was returned to service. I think the same could be done here.

My guess is there will be rebuilders that spring up to disassemble and test the cells, and replace the few bad ones with other used ones of similar vintage and capacity, and sell the used / repaired packs. A few weak cells can really hurt the pack as a whole.

When I used to race R/C everyone had their secret methods of treating cells to boost Voltage and or Capacity, and I'm sure there is some money to be made if someone can recondition the cells to get some of their lost capacity back. Perhaps take the packs apart, hook them up to a windmill, and cycle them through a few test and re-conditioning charge cycles to bring some of their life back while making a little coin as grid storage.

1. collect old EV batteries
2. disassemble
3. test (PROFIT!!!)
4. sort
5. recondition (PROFIT!!!)
6. reassemble
7. PROFIT!!!

about 3 months ago

.NET Native Compilation Preview Released

EETech1 Re:Open source compiler (217 comments)

I know... I hate having to use those darn line numbers..

And don't even get me started on the three letter variable names!!!

Qbasic FTW!

about 4 months ago

Algorithm Reveals Objects Hidden Behind Other Things In Camera Phone Images

EETech1 Re:Frosted glass, huh? (85 comments)

Better be careful what kind of tape you use!

about 4 months ago

Ford Dumping Windows For QNX In New Vehicles

EETech1 Re:Can't it be like Star Trek (314 comments)

Many fuel injected performance cars already do that. When the ECM detects you are at WOT, it will shut off the A/C compressor to get a few extra horsepower.

My 5.0L Mustang had A/C cut. I used to drag race it (:Yes with the A/C on:) and 12 seconds later, when I got to the "Big End" of the 1/4 mile it would be blowing warm air out of the registers, but as soon as I let off the gas, it would cool down again!

I tried running it with the A/C turned off as well, but it made no difference in my elapsed times. Changing to a shorty belt that bypassed the A/C and power steering was good for a tenth of a second or so, but it was not worth the hassle of changing the belt all the time, and sweating my butt off while I was having fun.


about 5 months ago

Tesla Model S Caught Fire While Parked and Unplugged

EETech1 Re:Tesla not involved [Re:Not from the car?] (329 comments)

You are correct, with a CV joint the rotational angle in = rotational angle out, this is not the case with a traditional U joint. If you've ever been in a 4wd truck, and taken a tight turn, you can feel the lurching as the U joints change the wheel speeds. This is not what is at play in this case.

The issue is due to the geometry of the front wheels, and the fact that they want to "flop" outwards when torque is applied. Normally one wheel would counteract the other, but the uneven angles in the drivetrain cause an additional imbalance that can be felt in the steering wheel.

Wikipedia to the rescue again...
  The main component of torque steer occurs when the torques in the driveshaft and the hub are summed vectorially, giving a resultant torque vector around the steering pivot axis (kingpin). These torques can be substantial, and in the case of shafts making equal angles to the hub shafts, will oppose one another at the steering rack, and so will cancel. These torques are strongly influenced by the position of the driveshaft universal joint (CV joint) in relation to the steering axis, however due to other requirements such as achieving a small or negative scrub radius an optimum solution is not generally possible with simple suspension configurations such as Macpherson strut.



about 5 months ago

Plan 9 From Bell Labs Operating System Now Available Under GPLv2

EETech1 Re:I find it interesting (223 comments)

No she's a spreadsheet.

about 5 months ago

Tesla Model S Caught Fire While Parked and Unplugged

EETech1 Re:Tesla not involved [Re:Not from the car?] (329 comments)

Many front wheel drive vehicles already have a torque imbalance going to the front wheels because the CV axles are different lengths, and therefore are at different angles. This causes torque steer under acceleration. I'd venture to guess that it must not be that big of a deal because cars continue to be built that way.

Most front wheel drive "performance" cars have equal length CV axles to eliminate the issue.

If you had a failure of a wheel motor, you could just reduce the max power you allowed the other wheels to make so the car was drivable, and not too unwieldy during acceleration.

I agree that wheel motors are too much unsprung weight, and impractical for a number of other reasons though too. I worked on a diesel hybrid project that had large rare earth magnets mounted behind the flywheel, and that thing was downright dangerous to work on. Pulling tools right off the bench, and out of your hands. If you held on to them, you learned very quickly that it was a bad idea! Blood blisters galore! The amount of force in a large ring of rare earth magnets is incredible. We had to be very careful assembling it because if it got away from you, someone was getting hurt! You could stand them on edge, and feel them trying to jump off the wood cart and smash your tool box 4 feet away. Walk by an I beam in the shop, and it would leap right off the cart. It then took a small army with non-metallic pry tools to get it off the beam.

Not something you want to work on in the driveway! You don't just put it back together like installing a brake drum.


about 5 months ago

Tesla Model S Caught Fire While Parked and Unplugged

EETech1 Re:Tesla not involved [Re:Not from the car?] (329 comments)

The cheap brushless motors used in fans are switched by the magnetic field of the commutator, so putting more current to them will cause them to reach a higher peak voltage in the windings, and spin faster. They are very much like a DC brushed motor in that respect.

The larger higher powered motors are synchronous to the field applied to the windings, and putting more current to them will produce more torque, but the RPM is dependent on the frequency being sent by the drive electronics. If the frequency does not change, the RPM will not change either (besides perhaps 1-2% less slip).

If the motor has position feedback, you can use the encoder to tell the drive when to switch the field based on the position of the armature. In this mode, the large motor, will behave much like the small fan, or a DC motor, and vary the frequency, and resulting torque according to the power being sent to the armature, and the load on the output shaft. The RPM is simply the result.

There are also hybrid modes that allow for keeping very tight control on RPM, while allowing you to adjust the torque output for applications such as tension control, where you want one motor to pull something at the same speed as another motor, but want to keep a certain amount of slack or tension between them.

Example: unwinding a roll of paper, cutting it to width, and rewinding it. The drives keep the outer surface speeds of the two rolls matched as they change diameter, and keep perfect tension on the paper through the change in torque due to the changing diameters so the slitting operation works properly.

There are so many ways to make a motor turn, you can get exactly the properties you want from it.

about 5 months ago

Tesla Model S Caught Fire While Parked and Unplugged

EETech1 Re:Tesla not involved [Re:Not from the car?] (329 comments)

My ramblings were only about the synchronization of motors.

I'd agree on the differential being simpler (although not the modern computer controlled torque splitting design) but I'd also expect Tesla to have some top notch motor controls.

It's funny, I've been sent in to fix problems with our control systems to find the only problem to be a multi million dollar machine running for 2+ years without maintenance. I've often asked the plant managers if they'd treat their cars like that:) Production lines are there to make money, and shutting them down for maintenance (for some people) doesn't seem to make sense. They just run them, till they won't run anymore, then blame the electronics because the drive has a fault, but the drive is only faulted because it is trying to turn a gearbox that has gear teeth floating around in (what's left of) the gear lube.

When I was 17 I built a go-kart with a snowmobile engine, and a hydraulic (swash plate) transmission, ooohhh how I wish I could get one in my car... Lots of maintenance, if you consider twisted axles maintenance, which I soon did;)

I've seen lots of people struggle with their hydrostatic lawn mowers though, and we had a forklift with a hydrostatic transmission that has claimed it's fair share of walls too:) although Case should never have put the shifter pedal where the creeper pedal is on every other fork lift in the world...


about 5 months ago


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