Bioinstrumentation

User Generated

Zxzhgnve

Engineering

Description

this is the exam of Bioinstrumentation and i need you to solve them carefully.


.........................

Unformatted Attachment Preview

Problem 1 (10 pts): You measure the following signal (in Figure 1) and each data point is shown as a green dot, with the measured signal being the blue trace. This signal is not what you had expected, instead the signal you were expecting is the one as depicted by the red curve. Describe what is happening and how might one compensate; be specific and use appropriate terminology 1.0 0.5 Signal Amplitude 0.0 -0.5 -1.0 0 2 3 4 5 Time Figure 1. Measured (green dots with blue line) and expected signal (red line) Problem 2 (10 pts): a) You are measuring surface EMG response and obtain an output of 2 mV, however, the true value is 2.25 mV. Comment about this in regards to accuracy. b) You take 5 measurements and obtain 2 mV each time - What does this mean in terms of accuracy and/or precision? Problem 3 (20 pts): You are given the following sensor calibration curves for sensor A and sensor B (Figure 2). a) What are the approximate sensitivities of each sensor and which sensor is more sensitive? b) What are the approximate offsets for each sensor? How does the offset affect the sensitivity of each sensor? Midterm Exam Bioinstrumentation Fall 2018 Pro c) What is the dynamic range for each sensor A? appropriate and why? d) You would like to measure displacements between +/- 4.5 mm. Which sensor would be most f) Related to part d, what might happen to your signal if you use the other sensor? 3.5 3 2.5 2 1.5 1 0.5 Output Voltage (mv) 0 -0.5 -1 -1.5 Sensor A -2 Sensor B -2.5 -3 -3.5 -5 -4.5 -4 -3.5 -3 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 Displacement (mm) Figure 2. Output voltage as a function of input displacement Problem 4 (12 pts): a) What is the difference between analog and digital representations of a signal? b) You need to resolve a measured signal to at least 3 mV accuracy. You have three analog-to- digital converters (ADC): i) 8-bit ADC, ii) 12-bit ADC, and iii) 16-bit ADC; assume that the voltage range is O V to 10 V minus one LSB. Which ADC(s) would be appropriate to use? c) Which ADC is the most accurate? Midterm Exam Bioinstrumentation Fall 2018 3 method over another? Explain. Problem 5 (10 pts): You are measuring arterial blood pressure (Table 1 & figures below). a) For the method tied to each mode (i.e., direct and indirect), why might you choose when Table 1. Information for Problem 5 Flushing solution Mode Measurand/Physiologic Parameter Range of Parameter (mm Hg) Stopcock Signal Frequency (Hz) Method Catheter Diaphragm Direct 10 to 400 0 (or dc) to 50 Needle- Catheter Method Strain gauge wires Blood Pressure, Arterial Blood Pressure transducer Indirect 25 to 400 0 (or dc) to 60 Cuff (non- invasive) b) You decide to do an indirect measurement and are now trying to select a sensor (Table 2 below). Which sensor would you choose and why? Table 2. Sensor Information for Problem 5 Pressure Range (mm Hg) Dynamic Characteristics Sensor C 10 to 200 O to 30Hz 10 to 600 Sensor D O to 120Hz Problem 6 (5 pts): The electrocardiogram (ECG or EKG) is a diagnostic tool that is routinely used to assess the electrical and muscular functions of the heart. Figure 3 (bottom) shows a corrupted signal and Figure 3 (top) shows the signal you were expecting to measure. How might you obtain the top, uncorrupted signal? 2 ECG (noise-free) Q 1 1.5 000 1 0.5 0 -0.5 -1 50 100 150 200 250 300 350 400 450 500 ECG + noise 2 1.5 1 0.5 -0.5 50 100 150 200 250 300 350 400 450 500 Figure 3. Uncorrupted signal tomb atude ist untede sigmail (bottom); time is on x-axis and Problem 7 (13 pts): Below is a list of factors that set the design criteria for bioinstrumentation. Properly identify each as a signal, medical, environmental, or an economic factor. a. Radiation/Heat Dissipation b. Extreme humidity c. Offset d. Cost e. Durability f. Equipment Interference g. Ergonomics h. Range i. Resolution j. Vibration k. Operating point I. Saturation m. Toxicity n. Biocompatibility 0. Lifetime Midterm Exam Bioinstrumentation Fall 2018 00 3), calculate the following: 5 Problem 8 (9 pts): Given the following you take 5 samples and obtain Output 1 (below in Table Table 3. Data Sample No. 1 Output 1 10 ĐWNA 15 16 12 5 12 a) Output 1 Mean b) Output 1 Standard deviation Problem 9 (9 pts): For the devices listed below, label each as Class 1, Class II, or Class III. a. contact lenses b. pacemaker c. wheelchair classil d. electronic defibrillator (which delivers electronic current to the heart) e. cochlear implant f. external hearing aid g. artificial heart Problem 10 (6 pts). A 1.35x104 M solution of [Ru(NH )(pyridine)]2+ has a transmittance of 13.2% at 406 nm in a 1.00 cm optical length. Using Beer's Law (below), what is the molar absorptivity of the complex? Beer's Law: = lo-e-6(d).doc 1: Intensity of energy with the sample lo: Intensity of energy with the sample c: Concentration of substance d: optical path length €(): Molar absorptivity coefficient as a function of wavelength (1) Transmittance: T= 101 Absorbance: A= In(1/0)= e().doc Problem 11 (5 pts). At 580 nm, the complex [Fe(SCN)]2+ has a molar absorptivity of 7.00x103 Mcm-1. Using Beer's Law, what is the absorbance of 2.50x10-5 M solution of the complex in a 5.00 cm optical length? Also, what is the transmittance? Midterm Exam Bioinstrumentation Fall 2018
Purchase answer to see full attachment
User generated content is uploaded by users for the purposes of learning and should be used following Studypool's honor code & terms of service.

Explanation & Answer

attached is my answer

Problem 1:
What is happening is that the expected signal has a much smaller wavelength than that of the
measured signal. A practical technique to apply a probability based meaning of the importance
is recommended in this note. Flag and foundation commitments are resolved from a likelihood
to fit dependent on shapes just, and the likelihood thickness disseminations of the
noteworthiness along these lines decided are observed to be of a Gaussian shape even with
little measurements.
Problem 2:
a) In terms of accuracy, the percentage difference is calculated by

%error =

2 mV − 2.25 mV

100%
2.25 mV
0.25 mV
 %error =
100%
2.25 mV
 %error = 11.1%
b) If we take 5 measurements and obtain 2 mV each time; in terms of accuracy and precision, it
means that the surface EMG response is measured with the per cent error of 11% most of the
time.
Problem 3:
a) The approximate sensitivities of sensor A are calculated by

slope =

3 − ( −2 )
5 − ( −5 )

5
10
1
 slope =
2
 slope =

The approximate sensitivities of sensor B are calculated by

slope =

3 − ( −2 )
5 − ( −5 )

...


Anonymous
I was stuck on this subject and a friend recommended Studypool. I'm so glad I checked it out!

Studypool
4.7
Trustpilot
4.5
Sitejabber
4.4

Related Tags