Goal is to design a 4th - order iir butterworth bpf with center frequency 100 hz and bandwidth 40 hz. 1.choose an appropriate sampling rate (e. g., 300 hz) and determine the sample period.2.pre-warp the center, lower, and upper cutoff frequencies using, 휔휔푝푝=2푇푇tan(푇푇2휔휔)3.create a normalized analog 4th-order butterworth lpf (normalized filter will have cutoff of 1 rad/sec), and apply lp to bp transform, using the prewrapped frequencies in step 3. 4.apply bilinear transform to create a digital filter, 퐻퐻(푧푧). 5.plot frequency response of both bpfs,퐻퐻(푠푠) and 퐻퐻(푧푧).

A3-mm-thick panel of aluminum alloy (k 177 w/m-k, c 875 j/kg-k and ? = 2770 kg/m) is finished on both sides with an epoxy coating that must be cured at or above t,-150°c for at least 5 min. the production line for the curing operation involves two steps: (1) heating in a large oven with air at ts,0-175°c and a convection coefficient of h, 40 w/m2. k, and (2) cooling in a large chamber with air at 25°c and a con- vection coefficient of he 10 w/m2.k. the heating portion of the process is conducted over a time interval te which exceeds the ime required to reach 150°c by 5 min (h = r + 300 s). the coating has an emissivity of ? = 0.8, and the temperatures of the oven and chamber walls are 175 and 25°c, respectively. if the panel is placed in the oven at an initial temperature of 25°c and removed from the chamber at a safe-to-touch tempera ture of 37°c, what is the total elapsed time for the two-step curing operation?

Apressure vessel with an r/t 20 cannot be treated as thin walled vessel. a)-trune b)- false

The proportional limit is always greater than the yield strength for a material. a)-trune b)- false