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- Geosciences Faculty Publications and Presentations (3)
- Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works (1)
- IGC Proceedings (1997-2023) (1)
- School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations (1)
- School of Natural Resources: Dissertations, Theses, and Student Research (1)
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Articles 1 - 7 of 7
Full-Text Articles in Physical Sciences and Mathematics
Rich Information In The Acoustic Signals From Feeding And Grazing In Ruminants, Montague W. Demment, J. R. Galli, Carlos A. Cangiano, Emilio A. Laca
Rich Information In The Acoustic Signals From Feeding And Grazing In Ruminants, Montague W. Demment, J. R. Galli, Carlos A. Cangiano, Emilio A. Laca
IGC Proceedings (1997-2023)
Because of their impact on productivity and the environment, feeding behaviour, ingestion and rumination are critical to understand intake in grazing ruminants. Many systems, mainly mechanical, have been developed to measure ingestive behaviour. However, these systems have problems, including mechanical failure and the inability to distinguish between the complex jaw movements of prehension and ingestion (Laca et al., 1994). The sounds generated by these behaviours are rich in information that holds potential not only to distinguish and count behaviours, but also identify aspects of the nature of the foods ingested.
Bat Use Of Afforested And Encroached Patches And Their Role In Extending Bat Habitat Into The Nebraska Sandhills, Jacob L. Wagner
Bat Use Of Afforested And Encroached Patches And Their Role In Extending Bat Habitat Into The Nebraska Sandhills, Jacob L. Wagner
School of Natural Resources: Dissertations, Theses, and Student Research
The Nebraska Sandhills are currently undergoing a state shift to a redcedar dominated woodland due to anthropologic planting of eastern redcedar (Juniperus virginiana) and woody encroachment from the periphery of the Sandhills. To better understand this novel ecosystem and how bats are utilizing it I collected data at Barta Brothers Ranch with acoustic sensor grids consisting of 24 100m spaced acoustic sensors placed adjacent to planted windbreaks. Supplemental data from the Nebraska North American Bat Monitoring Program was used for data analysis at larger spatial scales. I used linear regressions and kriging interpolation maps to see how bats used windbreaks …
Volcano Infrasound: Progress And Future Directions, Jacob F. Anderson, Jeffrey B. Johnson
Volcano Infrasound: Progress And Future Directions, Jacob F. Anderson, Jeffrey B. Johnson
Geosciences Faculty Publications and Presentations
Over the past two decades (2000–2020), volcano infrasound (acoustic waves with frequencies less than 20 Hz propagating in the atmosphere) has evolved from an area of academic research to a useful monitoring tool. As a result, infrasound is routinely used by volcano observatories around the world to detect, locate, and characterize volcanic activity. It is particularly useful in confirming subaerial activity and monitoring remote eruptions, and it has shown promise in forecasting paroxysmal activity at open-vent systems. Fundamental research on volcano infrasound is providing substantial new insights on eruption dynamics and volcanic processes and will continue to do so over …
Validating Sidescan Sonar As A Fish Survey Tool Over Artificial Reefs, Michael A. Bollinger, Richard J. Kline
Validating Sidescan Sonar As A Fish Survey Tool Over Artificial Reefs, Michael A. Bollinger, Richard J. Kline
School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations
Visual observation methods via SCUBA are commonly used to survey artificial reef fish, although conditions in the Gulf of Mexico often make surveys difficult or even dangerous for divers. In this study, sidescan sonar was used to quantify water-column fish abundance and was compared to the established visual observation methods on SCUBA over four reef sites. Calibrated intensity values measured from sidescan sonar echo returns were used to estimate fish body length and to calculate scaled biomass (g/m2 reef) from a pooled fish length–weight relationship of commonly observed reef fish in the area. Sidescan sonar methods were equivalent to SCUBA …
Acoustic And Seismic Fields Of Hydraulic Jumps At Varying Froude Numbers, Timothy J. Ronan, Jonathan M. Lees, T. Dylan Mikesell, Jacob F. Anderson, Jeffrey B. Johnson
Acoustic And Seismic Fields Of Hydraulic Jumps At Varying Froude Numbers, Timothy J. Ronan, Jonathan M. Lees, T. Dylan Mikesell, Jacob F. Anderson, Jeffrey B. Johnson
Geosciences Faculty Publications and Presentations
Mechanisms that produce seismic and acoustic wavefields near rivers are poorly understood because of a lack of observations relating temporally dependent river conditions to the near-river seismoacoustic fields. This controlled study at the Harry W. Morrison Dam (HWMD) on the Boise River, Idaho, explores how temporal variation in fluvial systems affects surrounding acoustic and seismic fields. Adjusting the configuration of the HWMD changed the river bathymetry and therefore the form of the standing wave below the dam. The HWMD was adjusted to generate four distinct wave regimes that were parameterized through their dimensionless Froude numbers (Fr) and …
Mapping Thunder Sources By Inverting Acoustic And Electromagnetic Observations, J. F. Anderson, J. B. Johnson, R. O. Arechiga, R. J. Thomas
Mapping Thunder Sources By Inverting Acoustic And Electromagnetic Observations, J. F. Anderson, J. B. Johnson, R. O. Arechiga, R. J. Thomas
Geosciences Faculty Publications and Presentations
We present a new method of locating current flow in lightning strikes by inversion of thunder recordings constrained by Lightning Mapping Array observations. First, radio frequency (RF) pulses are connected to reconstruct conductive channels created by leaders. Then, acoustic signals that would be produced by current flow through each channel are forward modeled. The recorded thunder is considered to consist of a weighted superposition of these acoustic signals. We calculate the posterior distribution of acoustic source energy for each channel with a Markov Chain Monte Carlo inversion that fits power envelopes of modeled and recorded thunder; these results show which …
Microbial-Induced Heterogeneity In The Acoustic Properties Of Porous Media, Caroline A. Davis, Laura J. Pyrak-Nolte, Estella A. Atekwana, D. Dale, Werkema, Marisa E. Haugen
Microbial-Induced Heterogeneity In The Acoustic Properties Of Porous Media, Caroline A. Davis, Laura J. Pyrak-Nolte, Estella A. Atekwana, D. Dale, Werkema, Marisa E. Haugen
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
It is not known how biofilms affect seismic wave propagation in porous media. Such knowledge is critical for assessing the utility of seismic techniques for imaging biofilm development and their effects in field settings. Acoustic wave data were acquired over a two-dimensional region of a microbial-stimulated sand column and an unstimulated sand column. The acoustic signals from the unstimulated column were relatively uniform over the 2D scan region. The data from the microbial-stimulated column exhibited a high degree of spatial heterogeneity in the acoustic wave amplitude, with some regions exhibiting significant increases in attenuation while others exhibited decreases. Environmental scanning …