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User: JonathanR

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  1. Re:Original on SHA-1 Collisions for Meaningful Messages · · Score: 1

    How easy is it to incorporate a lot of garbage content into an executable?

  2. Original on SHA-1 Collisions for Meaningful Messages · · Score: 1

    So the original document that is trying to be forged/modified has to convienently have a "long nonsense part" after the tag. How real-world relevant is that?

  3. Quite simple to check file size also on SHA-1 Collisions for Meaningful Messages · · Score: 1

    I would have thought this not such a big issue for software developers who aren't incompetent.

  4. Re:Interview with Iranian Nuclear Chief on Iranian Heavy Water Nuke Plant Goes Online Today · · Score: 1

    I don't think they had the capability of sending an internet to President Truman back then

  5. Re:Interview with Iranian Nuclear Chief on Iranian Heavy Water Nuke Plant Goes Online Today · · Score: 1

    No, the question is not answered. IIRC, nukes were never used against Germany or Russia. Germany surrendered (May 7th) some three months before the bombing of Hiroshima (Aug 6) and Nagasaki (Aug 9). Your inference does not hold water.

  6. Re:Bright Future In Something on 11-year-old Proves Locks Not So Secure · · Score: 1

    Age 23 - Profit!

  7. Re:FYI on Computer Designed Car Sets Speed Record · · Score: 1

    I stand by every thing I said in my previous post.

    Sure, diesel cycle makes use of a detonation type combustion. But what does detonation produce? A rapid pressure rise in the cylinder. Ahhh.

    Unlike the diesel cycle, the Otto cycle requires ignition prior to TDC to achieve maximum BMEP, as a result, has a slower cylinder pressure rise. The Diesel cycle is not fuelled until TDC or very close to it. I'm not talking about the compression pressure rise, the rate of which is similar in magnitude for both cycles. Having said that, this is also faster (as a function of crank angle) with the diesel, as the compression ratio is higher.

    You are also totally incorrect in saying that diesels are "extremely rich-running". Nothing could be further from the truth. Diesel power/speed control is effected by fuelling timing and duration only. This can only be accommodated because they are inherently lean running, which is why they don't require throttling to maintain a near stoichometric fuel/air ratio for low speed/load operation.

    On the subject of energy density of the two fuels, ULP is typically around 32 MJ/litre, whereas diesel is around 39 MJ/litre. I'd hardly call this "exceedingly higher".

  8. Re:FYI on Computer Designed Car Sets Speed Record · · Score: 1

    Your post is almost correct.

    Flame speed is the RPM limiting factor for diesels.

    Volumetric efficiency (gas flow losses) is usually the limiting factor for the Otto cycle. Racing engines produce high power by maintaining a moderate amount of torque through to a high engine speed.

    Power = torque x engine speed.

    The drop off in torque past its peak is more than compensated by the increase in engine speed, up to a point. Hence power continues to incease with increasing engine speed, until gas flow efficiencies or flame speed limitations erode torque (BMEP) at a greater rate than the corresponding rise in engine speed.

  9. Re:FYI on Computer Designed Car Sets Speed Record · · Score: 2, Informative

    The diesel torque advantage (over the otto cycle) is due to the higher brake-mean-effective-pressure of that thermodynamic cycle.

    The volumetric fuel efficiency (mpg) advantage is in part due to the higher LHV (lower heating value) of diesel fuel.

    The energy efficiency advantage is, in part, due to the higher compression ratio typically used and in part due to the lack of induction throttling for power control (less pumping losses). The noise generated by diesels is mostly due to the fast cylinder pressure rise. Diesel noise reduction is partly effected by compromising the ideal diesel cycle (and some of the related efficiencies).

  10. Re:bomb makers can now target americans on E-Passport In the Works · · Score: 1

    The Yanks don't need radio beacons. Normally it's done in with audio frequency.

  11. Re:Hysterical over nothing, data doesn't leave car on Car Owners to be Notified of Blackboxes in Vehicle · · Score: 1

    Does this mean that the ECU becomes non-functional after three events? Or is it that the data from a fourth event is discarded? If the ECU remains functional, it would be relatively easy to simulate the event three times to fill the memory, which would eliminate the recording of the real event.

  12. Grocery Stores? on Pay By Touch Goes Online · · Score: 4, Funny

    What about strip clubs?

  13. Re:Like in humid environments on How to Run a Computer in a Sub-Zero Environment? · · Score: 1

    Water will not condense on anything that is warmer than ambient. The most likely cause of condensation would be ambient temperature cycling, whereby components become cooler than the ambient dewpoint. If you can keep the atmosphere at a relatively constant temperature, with an RH margin suitable for the likely temperature range expected, there will be no condensation problems.

    On the other hand, whether there are any reasons from an electronics POV (aside from condensation) that require a higher ambient temperature, I cannot tell . I'm a mechanical engineer, not an electronics engineer (IANAEE).

  14. Re:RIAA Lawyer's office is like 1 mile away... on RIAA Wants to Depose Dead Defendant's Children · · Score: 2, Funny

    Arrange a hearse to deliver an empty casket to reception...

    UNDERTAKER: Our client has an appointment with with Mr Bainwol, sir.

  15. Approval Ratings on BBC Reports UK-U.S. Terror Plot Foiled · · Score: 0, Troll

    Ahhh.... Tony Blair's approval ratings must have hit the low level alarm setpoint.

  16. Re:Prediction on CEO Shawn Hogan Takes on MPAA · · Score: 1

    In a couple of months, we'll be reading about it again on /.

  17. Re:Racism on Western Union Blocking Money Transfers to Arabs · · Score: 1
    ...there are many, many non-Islamic terrorist groups.

    Wot? You mean the US Army, the USAF and the USMC, amongst others?
  18. Re:Human centrifuge - the Gravitron on The Physics of Superman · · Score: 1

    ...and I bet the rides where you succeded with your little ploy were of much longer in duration than usual.

  19. Re:As a buyer it costs money if anything goes wron on Can eBay Make You Rich? · · Score: 1

    I recently purchased from a Hong Kong based vendor, and was suspicious of their credibility, so I contacted several of the recent and not-so-recent buyers to get more detailed feedback. It was only after I received that feedback, that I was willing to put my moolah on the line (about AUD 160.00)

  20. Nearly 100% on Hurricane Simulator to Destroy Full Size Building · · Score: 0, Redundant

    At well above 90% CPU load, there wouldn't be too much more room to move eh?

  21. Re:Wow! Who knew? on Immunizing the Internet · · Score: 1

    You only eat buggers in Germany

  22. Re:The year was 1987 on NASA Holds Competition to Develop Space Vehicles · · Score: 1

    I don't think Nickel is getting rare, so much as energy is getting expensive. Thus the lower grade and Nickel deposits and alternative Nickel mineralisations are becoming more expensive to extract and process.
    I'd say you'd get quite a bit of conventional Nickel for your space program-sized budget

  23. Re:What century are you living in? on The Pentagon's Supersonic, Shape-Shifting Assassin · · Score: 1
    China could crash our economy into a zillion little shards . They have a strong economic incentive not to do that, but they could if they so chose.

    I would contend otherwise. I think such arguments are a further manifestation of the hubris caused by US petro-dollar hegemony.

    The US economy circa WWII was export driven in a similar fashon that China is now, excepting that the US manufacturing was directed to the war effort. So after WWII, the demand destruction of war commodities was replaced by domestic demand for domestic goods. Thus, the manufacturing machine developed during WWII was diverted to benefit the domestic population.

    I'd suggest that if the US economy tanked it, then you'd start to see a growth of domestic Chinese affluence.
  24. Re:Blu-Ray vs HD-DVD, the winner is... on Toshiba Subsidizes $200/Unit on New HD Player · · Score: 1

    I'd counter this by pointing out the ho-hum reception that this high-def stuff is receiving. I mean, we've learned to accept mp3 for audio. DVD is ok for video, mostly, and digital cameras are plateauing at about 8MP, so what other senses do we need all such space for more 0's and 1's?

    Also, given that most processes are IO bound nowdays, simply making storage bigger is only going to make the wait longer.

  25. Re:Observation. on Summer Camps Join Fray Against MySpace · · Score: 3, Interesting

    MySpace already works with parents. Since everything online that is public, is accessible to the parents, should they be the least bit interested in what their children are up to.

    Not that I'm saying that parents should merely engage in covert snooping, but it certainly is a tool for them to get to understand what goes through the minds of their offspring.