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    Question on Discrete Parameter Markov Chains

    It is no longer necessary for you to answer this question as I have just discovered the answer elsewhere.
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    Question on Discrete Parameter Markov Chains

    I am required to find a formula expressing the probability of return to some state in a Markov chain at time n in terms of the probability of return to that state at time n - k and the probability of first return at time k. I cannot find this in my notes, and I have tried looking at several...
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    Satellites: Radiation Pressure

    Radiation pressure is often liable to induce roations in spacecraft as well as translations. The rotations can be compensated for with the spacecraft's attitude control system (e.g. reaction wheels). If the translations induce a significant deviation from the intended path, these can be...
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    Notebook Battery

    I have an Acer TravelMate C110, which is a small table PC, and I bought it just over a year ago. I like most things about it, but the one thing I hate is that the battery has only a paltry 1800mAh charge. My brother has a small non-tablet notebook of a similar size whose battery has a charge of...
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    Compensation using thermistor

    I suppose if some property of a circuit changes with temperature, and that change can be compensated for by a change in resistance, then that is the compensation they might be alluding to.
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    Alternative power source for garage.

    Did you not read the damned opening post? I already said that I cannot do that, it is illegal. Otherwise I would have done it. :rolleyes:
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    Alternative power source for garage.

    It would be far cheaper to open the door manually each time I want to use the garage. That's not the point. Why does anyone want to install an electric garage door opener? Because they want the door to open easliy and conveniently. If I have to manually charge the battery periodically, that is...
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    Alternative power source for garage.

    I live at about 51.5 degrees North latitude. As it is England, it is usually cloudy too. I don't have proper data, nor do I know where to get it for my area. I would like to mount the panels flat on the roof so that they are not visible from the ground--it's a flat roof garage, about 8 feet...
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    Alternative power source for garage.

    Guys, Thanks for the input. You've all given me a lot to think about here, so I'll try and compose a more detailed response later when I've digested this information.
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    Alternative power source for garage.

    I have recently moved house, the problem is the garage is situated about 100 feet from the house along with the garages of my neighbors. There are several houses between ours and the garage, and there is no mains electricity over there. The previous owners actually had mains power in the garage...
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    What engineering is most in demand

    I think the question is one to do with the demand for aerospace engineers in the job market. I suppose it depends where you are.
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    Artificial Neural Networks

    What's the trend in the current state of the art? Are neural networks common in hardware form?
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    News The Killing of the Superconducting Supercollider

    It's strange that they do not include an option to summarise the vote by party affiliation amongst the other summaries. But anyway, a quick tally and I determined this: It appears at the time there were 56 Democrat senators and 44 Republican. 26 Democrats voted Yea and 29 Nay with one not...
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    Artificial Neural Networks

    Are artificial neural networks emulated on a traditional computer, or do they have a processor of artificial neurons? That is, is a neural network a piece of software or hardware?
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    Help for solving for C and F please

    By the way, it is considered bad netiquette to post this in several sub-fora on the same forum. I understand that you could be in a hurry to get this solved, but if you post it in the appropriate sub-forum (homework help), people will get to it and assist you just as quickly.
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    Help for solving for C and F please

    Multiply both sides of the equation by C: CX_c = 1/(2πF) Then divide both sides by X_c: C = 1/(2πFX_c)
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    Speed light travels on earth and in our solar system

    The second one is closer to the truth. All observers measure the same velocity of light, irrespective of the velocity of the source. Light is doppler shifted depending upon the velocity of the source. It is 'redshifted' (wavelength increases) if the source is receeding and is 'blueshifted'...
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    Venus transit question

    Then it came from TRACE.
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    Venus transit question

    Over on another forum, someone posted this image of the transit from TRACE: http://vestige.lmsal.com/TRACE/transits/venus_2004/images/VenusTransit2004_1600small.gif [Broken] The apparent 'bobbing' motion of venus is the effect of parallax due to the satellite's orbit about the earth...
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    Venus transit question

    I don't think the field rotation is significant in this clip.
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    Looking for a good book

    Shouldn't there be a distinction made between celestial mechanics and astrodynamics? I thought that astrodynamics was the name given to the more practical engineering aspects of spacecraft dynamics, control and navigation. Whereas celestial mechanics is looking only a planets and their...
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    Equasions (help )

    A little late, but there are some books you might want to check out to assist with this sort of stuff: Practical Astronomy with your Calculator, Peter Duffett-Smith (Cambridge University Press). Practical Astronomy with your Personal Computer, Peter Duffett-Smith (Cambridge University...
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    Millikan's Experiment

    Millikan did two famous experiments. One measured the charge on the electron. The other verified Einstein's theoretical work on the photoelectric effect, and in doing so, measured Planck's constant.
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    Momentum in explosions

    The angles are given with the directions. East and South East are 45º apart. You can also find a compass bearing of the thrid piece.
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    Gcse PHysics coursework practical help

    I don't know what good Ohm's law will do as that is to do with resistance in electrical circuits. Perhaps you meant Hooke's law? That would be a good start. We can discuss a little of the theory. What you can do is think of the average force acting on the rubber bands. When no force is...
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    Gcse PHysics coursework practical help

    Its mass and its shape are also factors.
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    Calculus problem.

    How? Using the quotient rule for the second term? Is that what you did?
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    Tension force

    ? Haven't you already posted that?
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