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A Laser-Based Powder Bed Fusion Additive Manufacturing company believes that the tensile strength of one artifact in their experiment, a machine tensile bar (MTB), is significantly less than the tensile strength of another artifact they produced, a rough tensile bar (RTB). The tensile strength of four samples of both the MTB and RTB were measured (listed below).  MTB 1246 psi 1351 psi 1294 psi 1317 psi RTB 1365 psi 1283 psi 1322 psi 1378 psi This copywritten question is part of an exam or quiz at Arizona State Univerisity. It may not be posted or reproduced without permission from Dr. D. McCarville, Dr. L. Chattin, and Arizona State University What would be a reasonable analysis approach using this data?  Select the best answer below.

A local plant produces an item used in road construction.   Estimated fixed costs are $73,000 per month.  The estimated revenue is $[x] per item and the estimated variable cost is $[y] per item.   This copywritten question is part of an exam or quiz at Arizona State Univerisity. It may not be posted or reproduced without permission from Dr. D. McCarville, Dr. L. Chattin, and Arizona State University How many items per month must the plant produce in order to make money? Enter your answer to the nearest integer. 

The scores of a random sample of ten students on an IEE 380 exam are 99, 77, 81, 62, 86, 74, 75, 60, 85, 95.    This copywritten question is part of an exam or quiz at Arizona State Univerisity. It may not be posted or reproduced without permission from Dr. D. McCarville, Dr. L. Chattin, and Arizona State University If you wanted to do a hypothesis test to determine if the population variance is less than 7.3, which test statistic would you use? Select the best answer. 

This copywritten question is part of an exam or quiz at Arizona State University. It may not be posted or reproduced without permission from Dr. D. McCarville, Dr. L. Chattin, and Arizona State University.Choose the correct sentence below.    

Problem 2: (25 points) The parameters of a doubly fed induction generator are given below. The stator is connected to a three-phase grid at 600 V RMS (line-line) and 60 Hz.  It is given that the rotor speed (electrical rad/s), .  (a) Draw the per-phase equivalent circuit corresponding to the given operating condition and parameters (b) Using grid voltage as the reference phasor , it is given that the voltage across the magnetizing inductance is .  Calculate the phasors . (c) Calculate the total power injected into the grid.

Problem 4: (a) (13 points) Consider a 2-pole PMSM wind generator system delivering 2 MW with a rotor speed of 3000 RPM. Its parameters are . The d axis is aligned with the rotor position, which is given to be -900 at t = 0. The flux linkage in the d-axis winding due to the rotor magnets, . Assume kE = 1. Draw the per-phase equivalent circuit and calculate the phase ‘a’ current.   (b) (12 points) Briefly explain (a short paragraph or a few bullet points) each of the following. (1) Volt-VAR control and (2) Super-synchronous mode of operation in DFIG

Problem 1: (25 points) (a) Consider a three-phase, two-level converter with dc link voltage of 1000 V.  The CCA value of the line-line voltage generated by the converter is 480 V RMS at 60 Hz.  The switching frequency is 20 kHz. Using space vector PWM, plot the instantaneous for one switching period around t = 8 ms.  Clearly indicate the CCA value of each quantity also at 8 ms. (b) What is the maximum RMS line-line voltage that can be generated from the given 1000V dc link voltage using space vector PWM?

Which of the following is true of symptoms associated with psychiatric disorders? 

List 2 functions of the skin in the human body.

List 2 OT goals associated with burn injuries. Goals can be from the acute, emergent, or rehabilitation phase.