Recent content by es

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    Best Calculator for Matrix/Linear Algebra?

    my nose! of course. I have been doing this linear algebra thing all wrong...
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    Improve Network Performance with Delay Control for Send and Receive Circuits

    Oh ya, the relevant google searches are Network traffic management or Network traffic shaping
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    Improve Network Performance with Delay Control for Send and Receive Circuits

    Depends on the implementation of your particular network. But for most consumer networks on the market today, I would say the answer is no. However, this is something that can be controlled in software. For example: http://www.faqs.org/docs/Linux-HOWTO/Bandwidth-Limiting-HOWTO.html
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    Solving Simple Limit Problem Without Substitution

    Yipe. For some reason I though 1-x would be the numerator. Boy do I feel sheepish. :) Thanks for the help!
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    Solving Simple Limit Problem Without Substitution

    I tutor high school students in Calc and the other day I came across this problem. Limit of (1-Sqrt(x-2))/(x-3) as x->3 I tried coaching the student on how to simplify the expression and in the end I just showed him this substitution. Let u=Sqrt(x-2) Then (1-Sqrt(x-2))/(x-3) =...
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    Deriving the 3D Wave Equation: A Comprehensive Explanation

    Not sure what you mean by 3 dimensional case but I think it is just a definition. If you see an equation of the form U_tt = U_xx + U_yy + U_zz we choose to call it the wave equation in three dimensions.
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    Probability problem - Test Cheaters

    I agree with Gokul43201 and think that the chi-squared test would be the best way to go about measuring the similarity of tests to Jane. Then you could see if there is a correlation between closeness to Jane and similarity to Jane's test. However, keep in mind this just says that there is a...
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    Explaining Why (-1)(-1)=1 in College Algebra

    Personally, I think if they don't get DaveC's argument then you're going to have much bigger problems on your hands. But if it were me, I would present Arildno's demonstration and conclude with if a negative multiplied by a negative is not defined to be positive then a multiplication operation...
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    What chip can I use to boost IR signal for my projector?

    If you can get by with the lower switching frequency then another simple solution to boosting the output current is using the opamp to drive a bipolar transistor base current like figure two in this ap note. http://www.supertex.com/pdf/app_notes/AN-D14.pdf
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    What chip can I use to boost IR signal for my projector?

    Oh! I did misunderstand your question. Sorry about that. I think you just want to know how to generate enough current for the LED. For this I would recommend using a LED driver IC such as http://focus.ti.com/lit/ds/symlink/tps61060.pdf. Just have the receiver drive the enable pin. Don't worry...
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    What chip can I use to boost IR signal for my projector?

    Although I am not sure of the specifics of your project (I think you are talking about modifying the remote itself) an alternate solution might be better. How about building a repeater box. Something that receives IR at one end, copies the signal, and shoots out a new IR signal out the back via...
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    MOS capacitor flatband voltage

    I am not exactly sure what you are asking but I think the answer is, because that's how the physicists chose to define flatband voltage. I mean, a voltage is the potential difference between two points, so those are the points they picked. For why bands bend see section 2.3.5 of...
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    Some questions about the capacitor

    That's an interesting idea. I usually thought of this capacitance as a nuisance. Are there any typical applications for caps that use the PCB as the dielectric? I suppose the obivious one is to measure \epsilon_R directly for process control or something. Or since \epsilon_R is typically...
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    Can DC Motors Function Without a Commutator?

    http://en.wikipedia.org/wiki/Brushless_DC_electric_motor
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    Help Solving Non-Linear System

    Unfortunately no. I am trying to fit a set of data points, say {(x1,y1),(x2,y2),...,(xn,yn)}, to the parabola defined by y=a(x+p)^2+b(x+p)+c. Which is non-linear because p is also unknown (unless someone can figure out how to reduce it!) so the method of least squares does not apply. I have...
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