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% Document Info
\author{Alyssabruestle1}
\pdfinfo{
  /Title (spi-board-review.pdf)
  /Creator (Cheatography)
  /Author (Alyssabruestle1)
  /Subject (SPI Board Review Cheat Sheet)
}

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\fancyhead[L]{
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
    \SetRowColor{DarkBackground}
    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
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\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{SPI Board Review Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{Alyssabruestle1} via \textcolor{DarkBackground}{\uline{cheatography.com/170636/cs/37156/}}}
\end{tabulary}
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\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}Alyssabruestle1 \\
  \uline{cheatography.com/alyssabruestle1} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 17th February, 2023.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
  \SetRowColor{white}
  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
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\begin{multicols*}{3}

\begin{tabularx}{5.377cm}{x{1.89126 cm} x{3.08574 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Acoustic Variables}}  \tn
% Row 0
\SetRowColor{LightBackground}
Pressure (Pascals (Pa)): & concentration of force in an area \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Density (km/cm\textasciicircum{}3): & concentration of mass in a volume \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
Distance (cm or mm): & refers to the distance a particle moves. \tn 
% Row Count 6 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{Used to differentiate between the different types of waves (heat, light, sound etc). If one of the 3 variables have rhythmic oscillations then it is a sound waves.}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Basic Review}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{All waves carry what?} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Energy} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Sound must travel in a \_\_\_\_\_\_ line} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Straight} \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{ALL sound waves are \_\_\_\_\_\_ and \_\_\_\_\_\_} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Longitudinal and mechanical} \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Sound (mechanical waves) need a \_\_\_\_\_\_ to travel through} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Medium} \tn 
% Row Count 9 (+ 3)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Molecules in a sound wave are \_\_\_\_\_\_\_\_ and \_\_\_\_\_\_\_.} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Compressed and rarefied} \tn 
% Row Count 12 (+ 3)
% Row 5
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Acoustic Propagation Properties} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}The effect medium has on sound waves.} \tn 
% Row Count 14 (+ 2)
% Row 6
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Bioeffects} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}The effects sound waves have on body tissue.} \tn 
% Row Count 16 (+ 2)
% Row 7
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{What are 2 types of mechanical waves?} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Transverse and longitudinal.} \tn 
% Row Count 18 (+ 2)
% Row 8
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{What is the average speed of sound in soft tissue?} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}1540 m/s OR 1.54 mm} \tn 
% Row Count 20 (+ 2)
% Row 9
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Another word for stiffness is?} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Bulk modulus} \tn 
% Row Count 22 (+ 2)
% Row 10
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Stiffness and speed are \_\_\_\_\_ related.} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Directly; increased speed = increased stiffness.} \tn 
% Row Count 25 (+ 3)
% Row 11
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Speed and density are \_\_\_\_\_ related.} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Inversely; increased speed = decreased density.} \tn 
% Row Count 27 (+ 2)
% Row 12
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Sound travels the same speed no matter what \_\_\_\_\_.} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Frequency; 5Mhz probe and 15 Mhz probe will travel at the same speed.} \tn 
% Row Count 30 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{1.05271 cm} x{1.78503 cm} x{1.73926 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{3}{x{5.377cm}}{\bf\textcolor{white}{Acoustic Parameters}}  \tn
% Row 0
\SetRowColor{LightBackground}
Period \seqsplit{(microseconds):} & Time it take to complete one cycle. & Source, NO \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
\seqsplit{Frequency} (MHz): & \# of cycles per second. & Source, NO \tn 
% Row Count 5 (+ 2)
% Row 2
\SetRowColor{LightBackground}
Power (Watts): & Rate of energy & Source, YES by adjusting output power. \tn 
% Row Count 8 (+ 3)
% Row 3
\SetRowColor{white}
\seqsplit{Intensity} (W/cm\textasciicircum{}2) & Concentration of energy. & Source, YES by adjusting output power. \tn 
% Row Count 11 (+ 3)
% Row 4
\SetRowColor{LightBackground}
\seqsplit{Amplitude} (Pa): & The difference between the baseline and peak of a wave (bigness). & Source, YES by adjusting output power. \tn 
% Row Count 16 (+ 5)
% Row 5
\SetRowColor{white}
\seqsplit{Wavelength} (mm): & Distance to complete one cycle. \seqsplit{(1.54mm/frequency)} & Source AND medium, NO \tn 
% Row Count 20 (+ 4)
% Row 6
\SetRowColor{LightBackground}
\seqsplit{Propagation} speed (m/s) & How fast a sound wave travels through a medium. & Medium, NO \tn 
% Row Count 24 (+ 4)
\hhline{>{\arrayrulecolor{DarkBackground}}---}
\SetRowColor{LightBackground}
\mymulticolumn{3}{x{5.377cm}}{{\bf{Used to define characteristics of a continuous wave (wave that is unable to produce an image).}} \newline - Period and frequency are reciprocals. \newline - Frequency is inversely related to period and wavelength. \newline - Wavelength and period are directly related. \newline - Propagation speed is determined by stiffness and density.}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}---}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Intensity}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Used to evaluate tissue exposure to sound energy} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Determines the effects sound has on tissue.} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Intensity is important when studying what?} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Bioeffects} \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{The strongest intensity is at they \_\_\_\_\_\_ of the beam.} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Center/Focus (smallest area).} \tn 
% Row Count 7 (+ 3)
% Row 3
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{What intensity is the most important when studying bioeffects?} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}SPTA} \tn 
% Row Count 10 (+ 3)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{SPTP is the \_\_\_\_\_\_\_ intensity} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Highest} \tn 
% Row Count 12 (+ 2)
% Row 5
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{SATA is the \_\_\_\_\_\_\_ intensity.} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Lowest} \tn 
% Row Count 14 (+ 2)
% Row 6
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{ALL intensities have units of?} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}W/cm\textasciicircum{}2   (power/area)} \tn 
% Row Count 16 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{1.51041 cm} x{1.51041 cm} x{1.55618 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{3}{x{5.377cm}}{\bf\textcolor{white}{5 Parameters of Pulsed Sound}}  \tn
% Row 0
\SetRowColor{LightBackground}
Pulse duration \seqsplit{(microseconds):} & Time is takes to complete one pulse. & Source, NO \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
Spatial Pulse Length (mm): & Distance it takes to complete one pulse. & Source, NO \tn 
% Row Count 7 (+ 4)
% Row 2
\SetRowColor{LightBackground}
Pulse Repetition Period (PRP): & Time from the start of one pulse to the start of the next (includes transmit and receiving time). & Source, YES by adjusting depth (Directly related). \tn 
% Row Count 15 (+ 8)
% Row 3
\SetRowColor{white}
Pulse Repetition Frequency (PRF) (kHz): & \# of pulses per second. & Source, Yes by adjusting depth (inversely related). \tn 
% Row Count 19 (+ 4)
% Row 4
\SetRowColor{LightBackground}
Duty Factor (\%): & Percentage of time that the pulse is on. & Source, YES by adjusting depth (inversely related). \tn 
% Row Count 23 (+ 4)
\hhline{>{\arrayrulecolor{DarkBackground}}---}
\SetRowColor{LightBackground}
\mymulticolumn{3}{x{5.377cm}}{Characteristics used to define a pulse wave (wave that is able to produce an image). \newline - A pulse is made up of multiple cycles. \newline - 3 out the 5 parameter can be adjusted using depth.}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}---}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{How Sound Travels Through Media}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Attenuation} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Decrease in power, intensity, and amplitude due to sound waves decreasing as they propagate through media.} \tn 
% Row Count 4 (+ 4)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Distance and attenuation are \_\_\_\_\_ related.} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Directly; increased distance = increased attenuation.} \tn 
% Row Count 7 (+ 3)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Frequency and attenuation are \_\_\_\_\_\_ related.} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Directly; increased frequency = increased attenuation.} \tn 
% Row Count 10 (+ 3)
% Row 3
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{3 processes that contribute to attenuation:} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}1. Reflection 2. Scattering 3. Absorption} \tn 
% Row Count 12 (+ 2)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{2 types of reflection (energy reflected back):} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}{\bf{1. Specular:}} smooth boundary, one direction  {\bf{2. Diffuse:}} irregular border, multiple directions.} \tn 
% Row Count 16 (+ 4)
% Row 5
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Scattering} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Waves redirected in many directions due to small tissue interface; when tissue is \textless{} wavelength. Directly related to frequency.} \tn 
% Row Count 20 (+ 4)
% Row 6
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Rayleigh scattering} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}When structures are MUCH smaller than the beams wavelength. EX: RBC. Rayleigh scattering = frequency\textasciicircum{}4. They are directly proportional; increased frequency = increased Rayleigh scattering.} \tn 
% Row Count 25 (+ 5)
% Row 7
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Absorption} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Ultrasonic energy is converted into heat. Directly related to frequency.} \tn 
% Row Count 28 (+ 3)
% Row 8
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Attenuation Coefficient (dB/cm)} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Used to compare the amount of attenuation in certain circumstances. Measured in decibels for when sound travels 1 cm.} \tn 
% Row Count 32 (+ 4)
\end{tabularx}
\par\addvspace{1.3em}

\vfill
\columnbreak
\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{How Sound Travels Through Media (cont)}}  \tn
% Row 9
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Total attenuation = Attenuation coefficient x Distance (cm)} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}EX: depth = 5cm AC = 2 dB/cm then total attenuation = 10 dB.} \tn 
% Row Count 4 (+ 4)
% Row 10
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Attenuation Coefficient in soft tissue = frequency/2} \tn 
% Row Count 6 (+ 2)
% Row 11
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Half layer thickness (penetration depth or half-boundary layer)} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}The distance sound travels in tissue that reduces intensity in half; Thin half layer = attenuates more} \tn 
% Row Count 11 (+ 5)
% Row 12
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Impedance (rayls)} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Resistance to sound traveling in a medium. Impedance = density x speed.} \tn 
% Row Count 14 (+ 3)
% Row 13
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Normal incidence} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Sound beam strikes boundary at 90 degrees (orthogonal, perpendicular, right). Reflection occurs if the boundaries have different impedances.} \tn 
% Row Count 18 (+ 4)
% Row 14
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Oblique incidence} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Sound beam strikes at any other angle other than 90 degrees; angle of incidence = angle of reflection.} \tn 
% Row Count 22 (+ 4)
% Row 15
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Incident intensity (\%)} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Intensity before striking boundary; incident intensity = reflected intensity + transmitted intensity.} \tn 
% Row Count 26 (+ 4)
% Row 16
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Reflected intensity} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Intensity of sound wave after striking boundary and retuning.} \tn 
% Row Count 29 (+ 3)
% Row 17
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Transmitted intensity} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}intensity of sound wave after striking boundary.} \tn 
% Row Count 32 (+ 3)
\end{tabularx}
\par\addvspace{1.3em}

\vfill
\columnbreak
\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{How Sound Travels Through Media (cont)}}  \tn
% Row 18
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Refraction} \tn 
\mymulticolumn{1}{x{5.377cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}Transmission with a bend. Can only occur IF 1. oblique incidence and 2. different propagation speeds of 2 media.} \tn 
% Row Count 4 (+ 4)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}