A pre-generated SBF scatterer containing all information required for
target strength modeling. The packaged geometry follows the sardine entry
distributed through the NOAA Fisheries KRM reference collection and
archived in the echoSMs resources. The object metadata identifies the
target as Sardinops sagax caerulea following Conti and Demer (2003).
Usage
data(sardine)Format
A named list with the following components:
- metadata
Relevant and identifying metadata (
list).- model_parameters
Specified model parameters (
list).- model
Model outputs and results (
list).- body
A list with:
rpos: Position matrix (x, yw, zU, zL; m).sound_speed: Flesh sound speed (\(c_{body}\), m/s).density: Flesh density (\(\rho_{body}\), kg/m\(^3\)).theta: Orientation relative to transducer (\(\theta_{body}\), radians).
- bladder
A list with:
rpos: Position matrix (x, yw, zU, zL; m).sound_speed: Bladder sound speed (\(c_{bladder}\), m/s).density: Bladder density (\(\rho_{bladder}\), kg/m\(^3\)).theta: Orientation relative to transducer (\(\theta_{bladder}\), radians).
- shape_parameters
A named list with:
body: A list describing the body:length: Body length (m).ncyl: Number of discrete cylinders.theta_units: Units for orientation angle.length_units: Units for length.
bladder: A list describing the swimbladder:length: Bladder length (m).ncyl: Number of discrete cylinders.theta_units: Units for orientation angle.length_units: Units for length.
Source
NOAA Fisheries KRM model reference collection
(https://www.fisheries.noaa.gov/data-tools/krm-model) and the
archived echoSMs resource set
(https://github.com/ices-tools-dev/echoSMs).
References
Conti, S.G., and Demer, D.A. (2003). Wide-bandwidth acoustical characterization of anchovy and sardine from reverberation measurements in an echoic tank. ICES Journal of Marine Science, 60, 617-624. doi:10.1016/S1054-3139(03)00056-0