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    Identifying type of feedback by looking at bode plot

    Homework Statement Below is the bode plot of return difference, 1+C(S)P(S) in a feedback system. Identify the frequencies where the feedback is large, negative, positive and negligible. P(S) = \frac{100}{s^2+2s+1} C(S) = \frac{220(s+50)}{s+200} Homework Equations Bode Plot, Feedback The...
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    Finding the state space model of a nonlinear system

    So the evaluation at (-15,5) becomes y'= \begin{pmatrix} 0 & 20 \\ -1 & -3 \end{pmatrix} ?
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    Finding the state space model of a nonlinear system

    Homework Statement The state space model of a nonlinear system is x'_1(t) = 2x^2_2(t) - 50 x'_2(t) = -x_1(t) - 3x_2(t) + u(t) Where x_1(t) and x_2(t) are the states, and u(t) is the input. The output of the system is x_2(t). Find the state space model of this system linearized at the...
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    Feedback Control Systems

    Homework Statement http://img24.imageshack.us/img24/9028/72841137.jpg [Broken] Homework Equations Routh-Hurwitz Stability Criterion The Attempt at a Solution For first question, you just write the Routh Array, make sure that the first row is all positive and you get Kmax = 1. Simple enough...
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    Find the coefficient of static friction help?

    You need the mass of the object at the least to solve the problem. Otherwise, this is an impossible problem.
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    Engineering Finding the impedance of a circuit

    Thevenin Theorem should work here. Find the equivalent impedance seen from the nodes a and g. (Hint : Fold from the right side to the left side)
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    Cmput: 2D parity error detection scheme

    You have to show your work if you want to receive detailed help. Here's something to start you off. Recall the definition of odd parity. The parity bit is set to 0 if you have an odd numbers of ones and it is set to 0 if you have an even number of ones. In your case, the last row (bottom)...
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    Compute the Z-transform of a^{-n} and step function

    Homework Statement Compute the Z-transform of x[n] = (0.5)^{-n} * u[n-1] And find the ROC (Region of Convergence) Homework Equations Z-Transform for discrete time x(z) = \sum_{n=0}^\infty x[n] * z^{-n} The Attempt at a Solution To solve this, I used the definition of...
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    An extremely easy question about NMOS

    Find the region of operation and drain current in an NMOS transistor. When they say region of operation, are they asking for the type of device (enhancement-mode or depletion-mode)? or the modes of operations (Cutoff, Triode or Saturation)?
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    Verilog arithmetic shift implementation.

    Here's my verilog code first of all module arithmetic_shift(input_num, op, shift_num, result); input [7:0] input_num; input [2:0] shift_num; input op; output reg [7:0] result; always @ (*) case(op) 0 : result = input_num <<< shift_num; 1 : result = input_num...
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    PNP Biploar Junction Transistor Energy Band Diagram

    Homework Statement Consider a PNP Biploar Junction Transistor uniformly doped in each region. Sketch the enegy ban ddiagram for the case when the transistor is biased in a)In thermal equilibrium b)biased in the active region c)biased in the cutoff (depletion) region Homework...
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    Signal Processing question

    As for the answer, the system is time invariant since the system does not explicitly depend on one of the inputs. As for your method of approaching this, even if you shift the input and run the samples through the system, you'd get the same output as running the signal through the system...
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    What does this arrow symbol mean?

    For the implification statement, -->, this is the semantic of it: If P is true, then the proposition is whatever Q is. Else, the proposition is true. Here is an example : Suppose P is false, then p-->q turns out to be true regardless of what q is. Suppose P is true and Q is true then...
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    Non ideal Operational Amplifier problem

    Majesticman, You must show some sort of work in order to receive help from us. As you suggested, convert the current source into voltage source, I think that's the best way to go. Then write Node-Voltage equations on the inputs of the opamps (NEVER AT THE OUTPUTS), remembering your ideal...
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    Finding impulse of a CT system

    Homework Statement A continuous-time system has the input/output relationship y(t) = \int_{-\infty}^{t} (t - \lambda + 2)x(\lambda) d\lambda Determine the impulse response h(t) of the system Homework Equations Convolution theorems y(t) = x(t) * h(t) Where y(t) is the output...
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    Truss,zero force member

    OOPS, I didn't see the load there. forget about CE and CF. If the roller is placed below the joint G, then in the Y direction, you know the summation of force turns out to be F_AG + F_Roller = 0 So we can't say AG is a zero force member. But, in the X direction, there's only one force you...
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    Truss,zero force member

    Zero force member CAN exist even if there is reaction. This is an example of it. If you sum the forces on G, you know there's a force acting on the X direction by the roller, but not the Y direction. therefore, Sum of force X = F_GF + F_Roller = 0 And if you try to sum the forces in the...
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    Truss,zero force member

    No, there are two more.
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    High Impedance in Verilog?

    High Impedance in Verilog???? Homework Statement Provide the correct Verilog text for encoding the following numerical values: A) A 16 bit hexadecimal with all positions in the high impedance state: B) An unsized hex number BEEF Homework Equations Verilog Problem. There is no...
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    Unit step

    If I understood your question correctly, you can do y = (t>=0) *Note : You have to predefine the vector t. for the unit step function y = u(t) Or use heaviside function.
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    Signals and Systems - Convolution

    Homework Statement http://img166.imageshack.us/img166/1162/untitledte2.jpg [Broken] Homework Equations Convolution y[n] = x[n] * h[n] The Attempt at a Solution I've never done convolutions going backwards.. right off the bat, I know I'll noly have 2 terms in the convolution...
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    Mesh-current method

    When you do mesh-currents on a circuit, you assume the directions of the current. Meaning you can ignore the polarity of the resistors. Don't worry, the algebra will take care of itself and show if the direction of the current is inversed (You will see a negative sign in front of it, if that is...
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    Engineering Digital circuit help

    Do you know how to do a Karnaugh map? If you can write the truth table for this, that is the easiest way to go about this problem.
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    Equation with a voltage divider

    Ugh.. this problem would be difficult with voltage divider, did you learn how to do Nodal Analysis? Because this problem would be surprisingly easy if you did. But I'm assuming you haven't. Is the value given for that voltage supply? Well at any rate, I think the way to tackle this problem...
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    Networking -Message Segmentation

    In modern packet-switched networks, the source host segments long, application-layer messages (for example, an image or a music file) into smaller packets and sends the packets into the network. The receiver then reassembles the packets back into the original message. This process is known as...
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    Networking -Message Segmentation

    Networking -Message Segmentation" Homework Statement Discuss the drawbacks of message segmentation. Homework Equations The Attempt at a Solution None. period. I cannot think of a single drawback on this system. It is the best method to send packets over any other methods...
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    Resistivity of a silicon

    Sorry, Amazon still hasn't sent me the textbook yet, so I had a hard time doing the homework, searching through internet, which led me to this website at end :( Thanks for your help
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    Resistivity of a silicon

    Homework Statement A silicon sample is doped with 5.0 X 10^19 donor atoms/cm^3 and 5.0 X 10^19 acceptor atmos/cm^3 a)What is its resistivity? b)Is this an insulator, conductor or semiconductor? c)Is this intrinsic material? Homework Equations No clue.. this is where I need help The...
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    Finding Free Electrons and Hole Concentration

    Homework Statement Silicon is doped with an Aluminum Concentration of 2 X 10^16 cm^-3 What are the free electron and hole concentrations at room temperature? What are the electron and hole mobilities at 300K? What is the majority carrier? What is the minority carrier? Homework...
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    [Thermodynamics (More like fluid actually)], Calculating absolute pressure

    Homework Statement http://img409.imageshack.us/img409/771/fluidcm5.jpg [Broken] Homework Equations F1/A1 = F2/A2 Pressure = Density * Height * Gravity The Attempt at a Solution I do not have a clue of how to solve this problem. Can anyone start me off and provide me couple of...
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