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  1. Re:Doesn't add up on Liquid Metal Capsules Used To Make Self-Healing Electronics · · Score: 2

    On integrated circuits it doesn't seem feasible. Basically you make the transistors and wires on ICs already as small as you can. To repair the wires on the IC you now need to insert capsules into the wires to do the automatic repair - so they would be way smaller than the wires. If you could manufacture these structures you'd make the wires smaller though and then you'd lose your ability to insert the microcapsules ... there is no way to win that race.

    Along the same lines, if you need twice the room to have the capsule next to the trace/wire, you might as well just make the wire twice as thick and figure that this makes it tougher. To determine if this technology is worthwhile, they would have to compare time to failure between their system and one with traces that occupied the same volume as their wire+capsule combination.

  2. Re:Why replace? on Ohio Supreme Court Drawn Into Magnetic Homes Case · · Score: 5, Informative

    The whole thing is BS. I work (mostly used to work) with MRI equipment, both supercon and smaller permanent magnet based instruments. I have some permanent magnets for building MRI machines that have a surface field strength of about 0.5T (5000 Gauss) which would crush your finger to a pulp if it ever got stuck between them, and are all but impossible to separate if they ever get near each other. I have routinely used a PC within a few feet of these without any ill effects. If I had to guess, the 5 Gauss line, normally considered the safe distance for magnetic storage media, is maybe a foot. If the steel beams in this house are magnetized, I would be amazed if the remanent magnetization was even 5 G. No chance of there being such a large field (this is 10x earth's field) more than a few inches away from the beams, regardless of their magnetization. Furthermore, a permanent magnet would have no effect on cordless phones of any kind. A static magnetic field has nothing to do with a 900 MHZ or whatever radio signal coming from the phone.

  3. This is not new on MRI Magnets Cause Nystagmus · · Score: 1

    Anyone who works around MRI magnets has known this for years. When I was a graduate student, you would always hear stories about people moving their hear around the end of the magnet (where the field gradient is highest) and making themselves dizzy.

  4. Re:Original paper? on Study Suggests Magnets Can Force You to Tell the Truth · · Score: 1

    Its not a static magnetic field, like with a permanent magnet at home, or with an MRI either. It is a TMS coil, which means repeated short burts of high magnetic field. The field does not stimulate the brain directly, but induces eddy currents which can modify brain function. TMS is effectively a friendly name for low (or sometimes not so low) level electric shock therepy.

  5. Re:Wait until after you start on Ask Slashdot: Best Second Major For a Mechanical Engineer? · · Score: 0

    I should add: don't discount specializations within the degree. For example, many schools will have a nuclear engineering option, automotive option, etc, for ME. If you are trying to do a double major in a hurry, you will probably end up using your upper year technical elective courses for your second degree, and end up with two degrees with little specialization in either. You may be better off focusing on the one degree, with a specialty.

  6. Wait until after you start on Ask Slashdot: Best Second Major For a Mechanical Engineer? · · Score: 1

    I was a bit confused by the summary, but my reply assumes that you have not yet started your ME degree and you want to concurrently take ME with something else, maybe CS, so that when you finish your undergrad education, you will have and ME degree and another degree (possibly CS).

    Part of my job is advising first year engineering students on their course selection. Your position is very common: people start with some idea about a minor / second degree they would like to take, and want to start taking courses to get them down that path right away. I try to encourage students to focus on their first degree, at least for the first two years. The reasons for this are mainly (1) engineering school is hard for many people, and before you start, you cannot be sure how good you are at it. You may find that a normal ME course load takes all your time and attention, and it would be a shame to immediately spread yourself thin, before you know what kind of a course load and subject range you can reasonably handle. (2) When you start engineering school, you may not have a good sense of what your interests are, even if you think you do. One of the best things about university is the range of degree programs you get exposed to, in a meaningful way that lets you explore your interests. In your first two years of ME, you will end up taking programming courses, physics, math, electrical engineering, chemical eng. / material science, etc. that will let you get a better sense of your interests and strengths. After a year or two, you will be in a much better position to decide what second major / minor you would like to pursue, if any.

    In your first year especially, the best thing you can do is use your electives, if available, to try out other subjects that interest you. One bit of advice if you have CS in mind though. Depending on the school, there are usually a number of different intro to programming courses, often one for CS, one for EE, one for the rest of engineering. If you need to take a first year CS course, see if the CS intro course will count for credit against your ME degree, and take that one instead (because the ME course will probably not count for CS) so you are not behind.

    Whatever you choose, do it out of interest and not based on your current perception of the job market. Five years from now (at least if you are doing two majors) there is no way to predict what will be popular.

  7. Re:Already dated. on Amir Taaki Answers Your Questions About Bitcoin · · Score: 0

    This post was interesting when I read it yesterday. I guess in fairness you changed the content arounf a bit,

  8. Re:subtle issues on Researcher Claims Magnets Can Affect Blood Viscosity · · Score: 1

    The magnetic field goes from 3/7.1 T in the magnet to a few gauss a short distance away. Moving through the field gradient induces eddy currents in your brain and causes the feeling. The effect would be worse around the ends of the magnet where the fringe field is larger.