Recent content by s3a

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    Trying to reconcile function composition problems with sets & formulas

    I know how to solve each of those problems. For the set one, I look at the output of the S and try to match it with the input of T and then take the pair (input_of_S, output_of_T), and I do that for each pair. As for the formula one, I just plug in x = g(y). My confusion lies in trying to...
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    I [(Linear) Temporal Logic] Are the given sentences consistent or not?

    All right, thank you. :) (And, sorry for the delay!)
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    I [(Linear) Temporal Logic] Are the given sentences consistent or not?

    Actually, the sub-sequence examples I mentioned are not valid because of the third or fourth sentences (□[p → O q] or □[q → O p]), depending on whether it's p or q that's the last element of the sub-sequence, and not because it is generally the case that all moments in time need to be "occupied"...
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    I [(Linear) Temporal Logic] Are the given sentences consistent or not?

    Also, is my (latest, corrected) diagram correct? It seems correct to me (since it seems to graphically represent both structures 1 and 2), but I'm asking just in case. And, is it correct to say that each of the subsequences I mentioned are each not sufficient to show that the set of sentences...
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    I [(Linear) Temporal Logic] Are the given sentences consistent or not?

    So, there are an infinite number of sequences but only two structures (where if even an infinite amount of sequences can be expressed as part of one formula, it's one structure)? And, I see, thanks. :)
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    I [(Linear) Temporal Logic] Are the given sentences consistent or not?

    "The second formula in your diagram is not consistent with the problem statement, containing a rogue additional 'not' sign." Oops! For what it's worth, here is the corrected version.: "Not necessarily true. For instance if both t1 and t2 are always active then statement 1 fails. You need to...
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    I [(Linear) Temporal Logic] Are the given sentences consistent or not?

    Consider the following set of sentences that represent the requirements of a multi-threaded system for two threads t1 and t2: □¬[(t1 active) ∧ (t2 active)]. □[(t1 active) ⊕ (t2 active)]. □[(t1 active) → O(t2 active)]. □[(t2 active) → O(t1 active)]. (Pretend the O letters are the circles...
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    Engineering Finding the natural frequency of transfer function (2s) / (3s^2+5s+2)

    Thanks for your input, Babadag, but I still don't fully understand how to compute the connection of the two "sub-circuits". I also don't understand why multiplying the two transfer functions isn't good enough. Could you please elaborate on those? Having said that, I figured out how to do the...
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    Engineering Finding the natural frequency of transfer function (2s) / (3s^2+5s+2)

    In the context of control systems, if I have a vibratory second-order system, (ω_n)^2 / [s^2 + 2ζ(ω_n) + (ω_n)^2], I know how to get the natural frequency ω_n. So, if I have something like 2 / (3s^2+5s+2), I know how to get the natural frequency ω_n. However, if I instead have something like...
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    Engineering Write the differential equation that's equivalent to this transfer function

    Basically, take a look at the "expanded form" of this (...
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    Engineering Write the differential equation that's equivalent to this transfer function

    Actually, is the going from (s^5 + 3s^4 + 2s^3 + 4s^2 + 5s + 2) C(s) = (s^4 + 2s^3 + 5s^2 + s + 1) R(s) to ##c^(5) + 3c^(4) + 2c^(3) + 4c^(2) + 5 c^(1) + 2c^(0) = r^(4) + 2r^(3) + 5r^(2) + r^(1) + r^(0)## from the L{f^(n) (t)} = ##s^n F(s) – s^{n-1} f(0) – s^{n-2} f'(0) - . . . – s f^(n-2)(0)...
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    Engineering Write the differential equation that's equivalent to this transfer function

    Maybe the solution is wrong? Since no one else answered, @Ssnow, could you please explain to me what you've done just in case you are in fact correct?
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    Engineering Write the differential equation that's equivalent to this transfer function

    I'm not sure of anything ( ;P ), but that ( ##r(t) = t^3 · u(t)## ) is technically what the solution says.
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    Engineering Write the differential equation that's equivalent to this transfer function

    I have the solution to the problem, and I mechanically, but not theoretically (basically, why do the C(s) and R(s) disappear?), understand how we go from ##(s^5 + 3s^4 + 2s^3 + 4s^2 + 5s + 2) C(s) = (s^4 + 2s^3 + 5s^2 + s + 1) R(s)## to ##c^{(5)}(t) + 3c^{(4)}(t) + 2c^{(3)}(t) + 4c^{(2)}(t) +...
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    Comp Sci RSA system with p=17, q=11 and e=3. Find m corresponding to c=156

    OFFICIAL SOLUTION: d=e^(-1) mod 160=107 mp= c^(d) mod p=7 mq:=c^(d) mod q=7 MY THOUGHTS: I understand how d = 107, but I got that by using m = (17-1)(11-1) = 160. What I don't understand is the next two lines (from the official solution). I am aware of the P = C^d mod n (decryption) formula...
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