Slashdot Mirror


User: Smidge204

Smidge204's activity in the archive.

Stories
0
Comments
2,715
First seen
Last seen
Profile
(view on slashdot.org)

Comments · 2,715

  1. Re:As big as a business card eh? on Web Server On a Business Card · · Score: 3, Interesting

    My car was exactly 0 processors in it. It has an AM-only radio which doesn't work, making the fuel gauge the most advanced piece of functional electronic equipment in the entire vehicle.

    For minimal impact, I would want it as small as possible with no moving parts. Using very little power is also a plus, since it would have to endure some pretty extreme environments (High humidity, High/Low temperatures) so it would go into a weatherproof enclosure - and heat becomes a concern.

    Something like this project would cost me under $50 to build, be small enough to mount inside the engine compartment (shortens and simplifies sensor wiring, no modification to the interior) and use very little power (no dead battery).

    I don't need a full PC to do the job, and such a thing would cost me at least $250 or so.
    =Smidge=

  2. Re:As big as a business card eh? on Web Server On a Business Card · · Score: 2, Insightful

    How about embedded or remote applications? HTTP is a very simple and widely implemented data exchange protocol that would be useful for a variety of tasks.

    For example, the microcontroller could do other things such as data logging, save them to the SD card, and cough up the data on HTTP request. Many network attached devices (especially routers, printers and plotters) contain embedded web servers... why not something of your own creation?

    I've considered installing a microcontroller in my car (which predates real onboard computers) to monitor things like speeds, pressures and temperatures. An HTTP interface would be a handy way to display the data on nearly any device and/or download raw data files without putting my own data protocol together.
    =Smidge=

  3. Re:how you're going to power the climber on Japanese Begin Working On Space Elevator · · Score: 1

    I think there were some reasons that powering it via the (carbon nanotube) cables was rejected previously:

    What does the electrical current/field do to the molecular strength of the material?

    What kind of electrical resistance are we talking about after 10,000 miles of cable? Nanotubes are not superconducting, and IIRC the kind that have really low electrical resistance are not the same as the kind that are really, really strong.

    What about interactions between a conductive cable and the Earth's magnetic field? What kind of forces might be generated running a current through them?

    DC or AC? I wold think the capacitance of such long cables would make AC totally impractical. DC is more efficient at those distances but also more dangerous as it requires much higher voltages.

    What about creating a path for upper-atmosphere ions to ground?

    =Smidge=

  4. Re:steps on Germany Fired Up Over Clean Coal · · Score: 4, Insightful

    There's certainly that, PLUS:

    It does not reduce our dependence on a limited resource. We're gonna run out eventually and the sooner we find an alternative the better.

    It just so happens that most, if not all of the truly "renewable" energy cycles we've found are also very eco-friendly. Kind of like a double-win.
    =Smidge=

  5. Re:hmm on To Purge Or Not To Purge Your Data · · Score: 1

    "Innocent until proven guilty" only applies in criminal cases. In civil cases - the kind a business is most likely to encounter - the exact opposite is typically true.

    =Smidge=

  6. Like hell on New York Issues RFID-Encoded Drivers Licenses · · Score: 1

    Thanks but no thanks. A simple ID number is enough to be tracked or have my identity stolen, and having one that can be read remotely is not an option. Knowing the DHS is involved it won't actually work and will be a joke on security issues, too.

    If I ever get a new ID card I think I'll toss it in the microwave the day I get it.
    =Smidge=

  7. Re:If "auto-steering" becomes popular... on Researchers Test Drive Bus With Automated Steering · · Score: 1

    I was thinking the same thing. A handful of powerful magnets is not exactly expensive or hard to come by.

    RFID chips might be a better choice. That could also provide more accurate navigation data, depending on how much info you can put in there to be reliably scanned as the vehicle whizzes by.

    =Smidge=

  8. Still a single vendor on Online Storage With a Twist · · Score: 1, Redundant

    Even though you don't want to tie yourself to a single vendor, that's still exactly what you're doing.

    Just ask yourself: If Wuala goes under, how will you get your data back?

    It doesn't sound like their client application does all the distribution itself, but rather everything is funneled to and from a central server that tracks the scattered data and makes sure enough mirrors are maintained for reliability.
    =Smidge=

  9. Re:IT Wins? on IT Vs. the Permanent Energy Crisis · · Score: 1

    Clearly you're not in the industry. I especially like your bait and switch tactics: Make a ridiculous and unrelated claim, then attack me for refuting it. My fault for falling for your strawman I guess.

    How many data center HVAC systems have you designed?
    =Smidge=

  10. Re:IT Wins? on IT Vs. the Permanent Energy Crisis · · Score: 2, Informative

    Mythbusters covered this. The startup current spike lasts for milliseconds, and is still quite small. So unless you plan to keep the light off for only a fraction of a second, you're saving energy.

    There might have been some modicum of truth behind this back when fluorescent lamps had thermal delay starters (even then we're talking seconds of operating energy, not even minutes), but anything newer than the 1970's will be efficient enough to not make a difference. Turn the light off.
    =Smidge=

  11. Re:IT Wins? on IT Vs. the Permanent Energy Crisis · · Score: 3, Informative

    No, I *don't* know what a heat pump is. I just size and specify them for commercial projects. Maybe you need to be a little less pedantic and understand that, outside of college, there is a practical difference between a "heat pump" and a "straight cool" DX* system.

    Specifically, a "Heat Pump" is a device that is designed to be reversible through control settings, as opposed to a "straight cool" unit which, while it might be PHYSICALLY reversed, is not designed to be.

    Heat pumps are also designed and rated to operate under different conditions. For example, your window AC unit is not likely designed to operate with an indoor ("evaporator") temp below about 50F and the outdoor ("condenser") temp below about 80F. A heat pump will be designed to operate comfortably at LEAST to an evaporator temp of 10F (most modern units are good enough to handle 0F).

    So yeah, thermodynamically they're the same but mechanically... not so much.

    Also, you're an idiot if you think that:

    1) It hasn't been done before. Daikin's 3-pipe "Heat Recovery" system is one example I have a lot of experience with. One outdoor condenser can operate multiple indoor fancoil units in a mix of heating and cooling modes simultaneously, using the reject heat from the cooling units as a source for the heating units with the balance of the heat/cool load handled by the outdoor coil. (I'm not a rep or otherwise affiliated with Daikin, BTW)

    2) All building heat is water, which you seem to imply by jumping directly into water temps. Hot air heating is very popular and very economical. Though hydronic heating certainly has its advantages you are unlikely to encounter any in low-rise, finely divided spaces like office buildings or large open-plan spaces like cube farms or warehouses. It's all forced air.**

    3) That a heat pump system can't or won't produce water at over 130F. Obviously we try to avoid that in cooling applications because it reduces efficiency (and with cooling towers promotes bacteria growth) but it'll happen if you set it up that way.

    I'd also like to know where you live that boilers run 140F to 120F. Around here where it actually gets cold we run 180F to 160F standard. Modern cast iron boilers can handle 30F dT (180 to 150) for better efficiency, and condensing steel boilers can easily handle return temps as low as 100F.

    =Smidge=
    * That's "DX" as in "Direct eXpansion" - another industry term you're likely to encounter. Opposed to "water-source heat pump" or "water-cooled condenser."

    ** Radiant heat flooring is, of course, a notable exception... And very nice if you're willing to pay for it. Only practical in new construction for obvious reasons.

  12. Re:IT Wins? on IT Vs. the Permanent Energy Crisis · · Score: 3, Interesting

    Nono, Dry ice is CO2. You have any idea how bad your carbon footprint will look if you use that?

    Here's one idea: Upgrade the server room AC to use heat pumps that can put the heat back into the building where it's needed.

    Another idea: Upgrade lighting and switching. Do all of the lights need to be on all of the time? Probably not. Add more switches to light only the parts of the room that need it, and occupancy sensors to make sure they're turned off when everyone leaves.
    =Smidge=

  13. Re:I disagree with what's written on the main page on DIY Hybrid Car Kit · · Score: 1

    No, the POWER/Weight ratio of an electric system is amazing compared to all but the most high-end gasoline engines (read: high-strung racing engines that get completely rebuilt after every use).

    It's the ENERGY/Weight ratio of batteries that pales compared to gasoline:

    Gasoline: 47 MJ/kg
    Pb-Acid Batt: 0.10 MJ/kg
    NiCd Batt: 0.20 MJ/kg
    Li-Ion Batt: 0.65 Mj/kg

    All values are approximate, of course.

    I other words, you can release stored energy from a battery at a much faster rate than you can from gasoline, but you can't store as much. There exists electric drag racers than can and do get under 12 seconds for the 1/4 - very much on par for gas engines.
    =Smidge=

  14. Re:I disagree with what's written on the main page on DIY Hybrid Car Kit · · Score: 1

    Drag racing generally isn't done on hills...

    =Smidge=

  15. Re:We need to stop manufacturing uneccessary cars. on DIY Hybrid Car Kit · · Score: 1

    An adapter kit as you describe would involve a clutch of some sort (to decouple the ICE) and essentially an oversize starer motor. not really THAT difficult but space might be an issue on some vehicles. The spur tooth of the flywheel is not intended for serious power transmission and would have to be swapped out for something that is. Don't forget lubrication either! Power transmission in constant-contact gears will need a recycling oiling system separate from the engine's.

    I have seen some kits that essentially mount an electric motor in place of the alternator (with appropriate electronics to charge the battery). The idea behind them is that, during periods of high load such as accelerating of hill climbing, these motors kick in to provide a little extra umph from a dedicated (but standard) battery. Not really a hybrid in the common sense of the word but not a bad option either depending on your driving habits... advantage here is you only need a pulley upgrade and an extra belt or two. They wear out but don't need lube.

    One thing I've thought about is a kit that replaces a portion of the drive shaft (rear wheel drive only, obviously). Electric motors do just fine at high RPMs and mounting one AFTER the transmission would improve efficiency, especially if it's an automatic. You also have more room to play with compared to the gap between engine and transmission.
    =Smidge=

  16. Building anything harms the environment on DIY Hybrid Car Kit · · Score: 2, Funny

    Building hybrids uses machinery that pollutes the environment. The solution? Don't build anything!

    That said, though, I looked up what would be required to build an all-electric vehicle and it was about $10k not including a vehicle to convert. Not a cheap hobby, unfortunately :/
    =Smidge=

  17. Re:Yeah! on Why Is the Internet So Infuriatingly Slow? · · Score: 2, Interesting

    ...or telecommuting (which I do a lot of)

    ...or videoconferencing

    ...or video/media streaming (YouTube et al)

    ...or using a third party VoIP application (Lots of this too)

    ...or doing any of a thousand other perfectly legal and legitimate reasons for a private individual to be sending or receiving lots of data. (Collaborative video projects as a personal anecdote)

    That said, I've been quite happy with FiOS in that I've never seen slowdown that I could attribute to the network itself. Part of the problem with cable is everyone on the block shares the same coax, and therefore the same bandwidth. FiOS has dedicated fiber runs from each house on the block to a head-end with very high bandwidth so there's no congestion there.
    =Smidge=

  18. Re:Pioneer Anomaly on Nuclear Decay May Vary With Earth-Sun Distance · · Score: 1

    Conservation of momentum?

    Radioisotope ejects a particle of non-zero mass at some velocity, and the remainder "recoils" from the ejection.

    Farther from sun -> Faster decay -> More mass ejected -> More momentum transferred... provided there is some kind of shield action to make the ejection of radiation directional... like a communication dish facing backwards towards earth.

    Is this enough to actually account for the Pioneer effect? No idea. I'll leave that up to the astrophysicists.
    =Smidge=

  19. Re:Carbon Dating on Nuclear Decay May Vary With Earth-Sun Distance · · Score: 1

    Probably not that much, really. The earth is only 6,000 years old, right? :)

    Joking aside:

    The cycle is relatively fast according to the graph in TFA - roughly annual. For things measured on a geological timescale this will average out pretty quickly. The important thing is to calibrate the reference accordingly.

    Of course, one the cause of the variation is pinned down we'll need to find out if there were any events in the past that might have caused substantial variances - that just might effect things.
    =Smidge=

  20. Re:Discussed this with an A/C tech friend. on Cost-Effective Server Room Air Conditioning? · · Score: 2, Informative

    That's a good way to go and I'm happy someone had enough sense to actually bring it up.

    The first step is to figure out how much cooling you actually need. If you're running commercial grade hardware the BTU/Hr heat output should be listed on the spec sheets. Add it up.

    If you're running unrated consumer grade hardware, consider looking for another job. Failing that, though, you can guestimate the heat load by adding up the max output of all the power supplies in the room, multiply by 1.25 (account for PSU efficiency, wiggle room) then convert watts to BTU/Hr by multiplying again by 3.41 (Not Pi - read carefully...)

    You'll need an AC unit that meets or exceeds this BTU/Hr rating. I would recommend a split/ductless system for ease of installation: One unit sits outside on a (preferably concrete) pad, the other half hangs on the wall, and you only need a fist-sized hole in the wall to run the pipes and wiring. Such an installation is a pro job, though.

    If you insist on going it alone, then portable AC units (as some have mentioned) are your second best bet - just need an exhaust duct, typically 6-8 inch diameter. Most units will evaporate any condensation into the exhaust air.
    =Smidge=

  21. Re:bzflag? on Examining Portal's Teleportation Code · · Score: 2, Interesting

    Yes no but not really. Vertical velocity is still vertical and horizontal velocity is still horizontal - just pointing in a different direction.

    With Portal (and it's predecessor Narbacular Drop) you can enter a portal on the floor and pop out a portal on a wall - vertical speed seamlessly becomes horizontal speed. And that works at any combination of angles. Add to that collision detection mid-portal and you have something just a little more than what BZFlag offers.

    Regarding the portals in Prey - I don't recall the portals being multi-directional but that game had a lot of funky physics in it so maybe I just don't remember. Also, the portals were all scripted in-place so they might have taken 'shortcuts' in the code to make them work.
    =Smidge=

  22. Re:You need a 500x microscope to read it on Rosetta Disk Designed For 2,000 Years Archive · · Score: 1

    Assuming some post-apoc sceanrio where mankind has been nuked back to the stone age, I think you just MIGHT be hard pressed to find someone with a 500X microscope. Even today, what percentage of the population has ready access to that kind of equipment? A 500X scope will run you at least $150 or so and is not exactly the kind of thing everyone has a need (or knowledge) to use.

    If the idea is to preserve data in a way totally independent of the circumstances surrounding its discovery, then requiring special equipment without even instructions for MAKING that equipment is stupid. Might as well just encode it as single-atom binary code - you'd be hard pressed to find a human in 2000 years from now "who would be digging around Earth in the first place" that wouldn't have ready access to electron microscopes and digital computers, right?

    =Smidge=

  23. Re:No on Let the Games Be Doped · · Score: 5, Interesting

    I say let's create a new set of games specifically for this reason. Let the "all natural" athletes have their own games, and we'll hold separate ones for those who sacrifice their own bodies for their performance.

    And why limit it to drugs? I say let them include anything and everything they want so long as it meets two requirements: First, it must be entirely self-contained (no power cables or wireless control links). Second, it must be operated directly from the user's nervous system (eg no buttons or switches - direct wetware interfaces only).

    Just think of the medical advances a pharmaceutically and cybernetically enhanced olympics could produce once it catches on!
    =Smidge=

  24. Re:Efficiency on Researchers Pave Way For Compressor-Free Refrigeration · · Score: 3, Interesting

    Well, peltier stacks use electric current. This method uses electric fields. In other words, it sounds like they use the polymer as a dialectric in a capacitor that is constantly charged and discharged. I know peltiers eat a lot of current, so depending on the capacitance of this new system the total power should be quite a bit less.

    Actually transporting the heat is another matter...
    =Smidge=

  25. Re:I don't get it on Why COBOL Could Come Back · · Score: 5, Insightful

    To expand on your analogy a little:

    You get your Japanese reference book, study hard, maybe even get your 1-kyuu certification (I think four years of study for that is typical for non-native speakers?)

    So you get a job translating. Your first project is to translate a recently discovered and unpublished early 1900's work written by someone like Touson Shimazaki or Mori Ougai. Good luck!

    =Smidge=