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WorksheetsCh. 16 & 17 Physics
Total questions: 44
Worksheet time: 4hrs 40mins
A method of reporting the extent to which a signal can vary and be still be accurately measured
(a)
Weak signals are below the systems _?
(a)
Signals that are too strong (a) the system
Units for Dynamic Range
dB
dB/cm
dB/cm^3
no unit
How does the dynamic range of information change the more it is processed?
Increases
Does not change
Decreases
List the components in order of highest to lowest dynamic range:
Display
Archive
Receiver
Scan Converter
Transducer
Reciever
Transducer
Scan Converter
Archive
Display
Archive
Display
Scan Converter
Receiver
Transducer
Transducer
Receiver
Scan Converter
Display
Archive
What is the dynamic range of the Transducer
10-30 dB
120 dB
100-120 dB
40-50 dB
What is the dynamic range of the Reciever
120 dB
100-120 dB
10-30 dB
20-30 dB
What is the dynamic range of the scan converter?
40-50 dB
10-30 dB
100-120 dB
120 dB
What is the dynamic range of the display?
10-30 dB
100-120 dB
40-50 dB
20-30 dB
What is the dynamic range of the archive?
10-30 dB
20-30 dB
120 dB
40-50 dB
What process eliminates potential errors when the component of an ultrasound system is wider/narrower than another component?
(a)
What are the requirements of compression?
The largest signal remains the largest
The smallest signal must be amplified
The smallest signal remains the smallest
The range of signals is reduced
Another description for dynamic range
(a)
Fewer gray shades
Narrow Dynamic Range
Wide Dynamic Range
Many shades of gray
Wide dynamic Range
Narrow Dynamic Range
image that contains only black and white, has the narrowest dynamic range
(a)
Image that contains many shades of gray and has the widest dynamic range, low contrast
(a)
_ is the creation of an image from sound reflections at twice the frequency of the transmitted sound
(a)
The frequency of sound created by the transducer and transmitted into the body
(a)
Twice the fundamental frequency
(a)
Harmonic frequency sound waves arise from ...
(a)
Creates images from sound reflections with the same frequency as the transducer frequency
Harmonic Imaging
Fundamental Imaging
Creates images from sound reflections that are twice the transducer frequency
Harmonic Imaging
Fundamental Imaging
a series of compressions and refractions
(a)
the harmonic frequency generated as sound travels through tissue where the energy is converted from the fundamental to harmonic frequency.
(a)
What happens to the strength of the harmonic sound wave as it travels in tissue?
Weakens
Grows
Stays the same
Where do tissue harmonic signals not exist at
(a)
When are tissue harmonics created?
(a)
Ultrasound technique where 2 pulses (1 positive, 1 negative) are emitted, the fundamental frequency is canceled out via destructive interference to improve overall image quality.
(a)
Ultrasound technique where the harmonics are extracted by sending 1 strong pulse and 1 weak pulse down each scan line
(a)
Agents that have a different acoustic fingerprint than tissue or blood, designed to create strong reflections
(a)
Harmonics created by interactions with contrast agents
(a)
When are contrast harmonics created
(a)
The amount of contrast harmonics produced can be estimated by a number called
(a)
What results in a lower M.I.
small pressure variation
Lower frequency
large pressure variation
higher frequency
What results in a higher M.I.
small pressure variation
large pressure variation
lower frequency
higher frequency
What is the relationship between M.I. and harmonic creation?
Linear
Nonlinear
Unrelated
What M.I. creates the strongest harmonics?
0.1-1.0
< 0.1
> 1.0
What M.I. produces only some harmonics?
0.1-1.0
>1.0
<0.1
What M.I produces no harmonics?
>0.1
<0.1
0..1-1.0
>1.0
Which harmonics produce the stronger harmonic signal?
Contrast Harmonics
Tissue Harmonics
How is M.I related to rarefactional pressure?
(a)
How is M.I. related to Frequency
(a)
