Relevant bibliographies by topics / High frequency gravity waves

Academic literature on the topic 'High frequency gravity waves'

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Published: 6 September 2023

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Journal articles on the topic "High frequency gravity waves"

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Hogan, P. A., and T. Futamase. "Some high‐frequency spherical gravity waves." Journal of Mathematical Physics 34, no. 1 (January 1993): 154–69. http://dx.doi.org/10.1063/1.530397.

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Hankinson, Mai C. N., M. J. Reeder, and T. P. Lane. "Gravity waves generated by convection during TWP-ICE: 2. High-frequency gravity waves." Journal of Geophysical Research: Atmospheres 119, no. 9 (May 13, 2014): 5257–68. http://dx.doi.org/10.1002/2013jd020726.

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Zhou, Chunyan, Dajun Wang, Song Shen, and Jing Tang Xing. "Nonlinear low-frequency gravity waves in a water-filled cylindrical vessel subjected to high-frequency excitations." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 469, no. 2153 (May 8, 2013): 20120536. http://dx.doi.org/10.1098/rspa.2012.0536.

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In the experiments of a water storage cylindrical shell, excited by a horizontal external force of sufficient large amplitude and high frequency, it has been observed that gravity water waves of low frequencies may be generated. This paper intends to investigate this phenomenon in order to reveal its mechanism. Considering nonlinear fluid–structure interactions, we derive the governing equations and the numerical equations describing the dynamics of the system, using a variational principle. Following the developed generalized equations, a four-mode approximation model is proposed with which an experimental case example is studied. Numerical calculation and spectrum analysis demonstrate that an external excitation with sufficient large amplitude and high frequency can produce gravity water waves with lower frequencies. The excitation magnitude and frequencies required for onset of the gravity waves are found based on the model. Transitions between different gravity waves are also revealed through the numerical analysis. The findings developed by this method are validated by available experimental observations.
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Perez, Iael, and Dragani Walter. "Spectral variability in high frequency in sea level and atmospheric pressure on Buenos Aires Coast, Argentina." Brazilian Journal of Oceanography 65, no. 1 (March 2017): 69–78. http://dx.doi.org/10.1590/s1679-87592017130506501.

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Abstract There are some observational evidences which support that atmospheric gravity waves constitute an efficient forcing for meteorological tsunamis (meteotsunamis) along the coast of Buenos Aires, Argentina. Meteotsunamis and atmospheric gravity waves, which propagate simultaneously on the sea surface and the atmosphere, respectively, are typical examples of non-stationary geophysical signals. The variability of meteotsunamis and atmospheric gravity waves recorded at Mar del Plata was investigated in this paper. Results obtained in this work reinforce the idea of a cause (atmospheric gravity waves) effect (meteotsunami) relationship, because wavelet spectra obtained from both signals resulted quite similar. However, several very short episodes of mod-erate/low activity of atmospheric gravity waves were detected without detecting meteotsunami activity. On the other hand, it was found that atmospheric gravity wave spectral energy can appear in the wavelets as a single or multiple burst as relatively long and irregular events or as regular wave packets. Results obtained in this paper provide original spectral data about atmospheric gravity waves along the coast of Buenos Aires. This information is useful to be included in realistic numerical models in order to investigate the genesis of this complex atmosphere-ocean interaction.
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Leena, P. P., M. Venkat Ratnam, B. V. Krishna Murthy, and S. Vijaya Bhaskara Rao. "Detection of high frequency gravity waves using high resolution radiosonde observations." Journal of Atmospheric and Solar-Terrestrial Physics 77 (March 2012): 254–59. http://dx.doi.org/10.1016/j.jastp.2012.01.003.

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Wang, Xiujuan, Lingkun Ran, Yanbin Qi, Zhongbao Jiang, Tian Yun, and Baofeng Jiao. "Analysis of Gravity Wave Characteristics during a Hailstone Event in the Cold Vortex of Northeast China." Atmosphere 14, no. 2 (February 20, 2023): 412. http://dx.doi.org/10.3390/atmos14020412.

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Based on high-resolution pressure data collected by a microbarograph and Fourier transform (FFT) data processing, a detailed analysis of the frequency spectra characteristics of gravity waves during a hailstone event in the cold vortex of Northeast China (NECV) on 9 September 2021 is presented. The results show that the deep NECV served as the large-scale circulation background for the hailstone event. The development of hailstones was closely related to gravity waves. In different hail stages, the frequency spectra characteristics of gravity waves were obviously different. One and a half hours before hailfall, there were gravity wave precursors with periods of 50–180 min and corresponding amplitudes ranging from 30 to 60 Pa. During hailfall, the center amplitudes of the gravity waves were approximately 50 Pa and 60 Pa, with the corresponding period ranges expanding to 60–70 min and 160–240 min. Simultaneously, hailstones initiated shorter periods (26–34 min) of gravity waves, with the amplitudes increasing to approximately 12–18 Pa. The relationship between hailstones and gravity waves was positive. After hailfall, gravity waves weakened and dissipated rapidly. As shown by the reconstructed gravity waves, key periods of gravity wave precursors ranged from 50–180 min, which preceded hailstones by several hours. When convection developed, there was thunderstorm high pressure and an outflow boundary. The airflow converged and diverged downstream, resulting in the formation of gravity waves and finally triggering hailfall. Gravity wave predecessors are significant for hail warnings and artificial hail suppression.
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McCord, Michael T., and Earl W. Carey. "Acoustic Visualization of Nonlinear Internal Gravity Waves Using an Improved High Frequency Sonar System." Marine Technology Society Journal 40, no. 1 (March 1, 2006): 97–102. http://dx.doi.org/10.4031/002533206787353691.

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High frequency sonar systems have been used by the Naval Research Laboratory to study nonlinear internal gravity waves and define the fine structure of ocean temperature and salinity layers that are found in coastal waters, usually within 130 meters of the surface. Of particular interest is the fine structure of these waves, which are being investigated using high sensitivity sonar systems that provide 1 m horizontal resolution and less than 8 cm vertical resolution. This article describes the integration of commercial and custom-designed components, including a recently patented transmitter-receiver switch. The significance of this T-R switch is that it improves the sensitivity of short-range sonar systems, enables a more refined measurement of nonlinear internal gravity waves, and could have broad industry applications.
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Deng, Y., and A. J. Ridley. "Simulation of non-hydrostatic gravity wave propagation in the upper atmosphere." Annales Geophysicae 32, no. 4 (April 24, 2014): 443–47. http://dx.doi.org/10.5194/angeo-32-443-2014.

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Abstract. The high-frequency and small horizontal scale gravity waves may be reflected and ducted in non-hydrostatic simulations, but usually propagate vertically in hydrostatic models. To examine gravity wave propagation, a preliminary study has been conducted with a global ionosphere–thermosphere model (GITM), which is a non-hydrostatic general circulation model for the upper atmosphere. GITM has been run regionally with a horizontal resolution of 0.2° long × 0.2° lat to resolve the gravity wave with wavelength of 250 km. A cosine wave oscillation with amplitude of 30 m s−1 has been applied to the zonal wind at the low boundary, and both high-frequency and low-frequency waves have been tested. In the high-frequency case, the gravity wave stays below 200 km, which indicates that the wave is reflected or ducted in propagation. The results are consistent with the theoretical analysis from the dispersion relationship when the wavelength is larger than the cutoff wavelength for the non-hydrostatic situation. However, the low-frequency wave propagates to the high altitudes during the whole simulation period, and the amplitude increases with height. This study shows that the non-hydrostatic model successfully reproduces the high-frequency gravity wave dissipation.
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Samson, J. C., R. A. Greenwald, J. M. Ruohoniemi, and K. B. Baker. "High-frequency radar observations of atmospheric gravity waves in the high-latitude ionosphere." Geophysical Research Letters 16, no. 8 (August 1989): 875–78. http://dx.doi.org/10.1029/gl016i008p00875.

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McKenzie, J. F. "On the unstable mode merging of gravity-inertial waves with Rossby waves." Annales Geophysicae 29, no. 8 (August 19, 2011): 1377–81. http://dx.doi.org/10.5194/angeo-29-1377-2011.

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Abstract. We recapitulate the results of the combined theory of gravity-inertial-Rossby waves in a rotating, stratified atmosphere. The system is shown to exhibit a "local" (JWKB) instability whenever the phase speed of the low-frequency-long wavelength westward propagating Rossby wave exceeds the phase speed ("Kelvin" speed) of the high frequency-short wavelength gravity-inertial wave. This condition ensures that mode merging, leading to instability, takes place in some intermediate band of frequencies and wave numbers. The contention that such an instability is "spurious" is not convincing. The energy source of the instability resides in the background enthalpy which can be released by the action of the gravitational buoyancy force, through the combined wave modes.
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Dissertations / Theses on the topic "High frequency gravity waves"

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Yu, Yonghui. "MODEL STUDIES OF TIME-DEPENDENT DUCTING FOR HIGH-FREQUENCY GRAVITY WAVES AND ASSOCIATED AIRGLOW RESPONSES IN THE UPPER ATMOSPHER." Doctoral diss., University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3623.

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This doctoral dissertation has mainly concentrated on modeling studies of shorter period acoustic-gravity waves propagating in the upper atmosphere. Several cases have been investigated in the literature, which are focusing on the propagation characteristics of high-frequency gravity wave packets. The dissertation consists of five main divisions of which each has its own significance to be addressed, and these five chapters are also bridged in order with each other to present a theme about gravity wave ducting dynamics, energetics, and airglows. The first chapter is served as an introduction of the general topic about atmospheric acoustic-gravity waves. Some of the historical backgrounds are provided as an interesting refreshment and also as a motivation reasoning this scientific research for decades. A new 2-D, time-dependent, and nonlinear model is introduced in the second chapter (the AGE-TIP model, acronymically named atmospheric gravity waves for the Earth plus tides and planetary waves). The model is developed during this entire doctoral study and has carried out almost all research results in this dissertation. The third chapter is a model application for shorter period gravity waves ducted in a thermally stratified atmosphere. In spite of mean winds the thermal ducting occurs because ducted waves are fairly common occurrences in airglow observations. One-dimensional Fourier analysis is applied to identify the ducted wave modes that reside within multiple thermal ducts. Besides, the vertical energy flux and the wave kinetic energy density are derived as wave diagnostic variables to better understand the time-resolved vertical transport of wave energy in the presence of multiple thermal ductings. The fourth chapter is also a model application for shorter period gravity waves, but it instead addresses the propagation of high-frequency gravity waves in the presence of mean background wind shears. The wind structure acts as a significant directional filter to the wave spectra and hence causes noticeable azimuthal variations at higher altitudes. In addition to the spectral analysis applied previously the wave action has been used to interpret the energy coupling between the waves and the mean flow among some atmospheric regions, where the waves are suspected to extract energy from the mean flow at some altitudes and release it to other altitudes. The fifth chapter is a concrete and substantial step connecting theoretical studies and realistic observations through nonlinearly coupling wave dynamic model with airglow chemical reactions. Simulated O (1S) (557.7 nm) airglow images are provided so that they can be compared with observational airglow images. These simulated airglow brightness variations response accordingly with minor species density fluctuations, which are due to propagating and ducting nonlinear gravity waves within related airglow layers. The thermal and wind structures plus the seasonal and geographical variabilities could significantly influence the observed airglow images. By control modeling studies the simulations can be used to collate with concurrent observed data, so that the incoherencies among them could be very useful to discover unknown physical processes behind the observed wave scenes.
Ph.D.
Department of Physics
Sciences
Physics PhD
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Malenova, Gabriela. "Uncertainty quantification for high frequency waves." Licentiate thesis, KTH, Numerisk analys, NA, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-186287.

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We consider high frequency waves satisfying the scalar wave equationwith highly oscillatory initial data. The speed of propagation of the mediumas well as the phase and amplitude of the initial data is assumed to beuncertain, described by a finite number of independent random variables withknown probability distributions. We introduce quantities of interest (QoIs)aslocal averages of the squared modulus of the wave solution, or itsderivatives.The regularity of these QoIs in terms of the input random parameters and thewavelength is important for uncertainty quantification methods based oninterpolation in the stochastic space. In particular, the size of thederivativesshould be bounded and independent of the wavelength. In the contributedpapers, we show that the QoIs indeed have this property, despite the highlyoscillatory character of the waves.

QC 20160510

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De, Deuge Maria. "Optical observations of gravity waves in the high-latitude thermosphere /." Title page, abstract and contents only, 1990. http://web4.library.adelaide.edu.au/theses/09SM/09smd485.pdf.

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Fozard, John Andrew. "Diffraction and scattering of high frequency waves." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433239.

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This thesis examines certain aspects of diffraction and scattering of high frequency waves, utilising and extending upon the Geometrical Theory of Diffraction (GTD). The first problem considered is that of scattering of electromagnetic plane waves by a perfectly conducting thin body, of aspect ratio O(k^1/2), where k is the dimensionless wavenumber. The edges of such a body have a radius of curvature which is comparable to the wavelength of the incident field, which lies inbetween the sharp and blunt cases traditionally treated by the GTD. The local problem of scattering by such an edge is that of a parabolic cylinder with the appropriate radius of curvature at the edge. The far field of the integral solution to this problem is examined using the method of steepest descents, extending the recent work of Tew [44]; in particular the behaviour of the field in the vicinity of the shadow boundaries is determined. These are fatter than those in the sharp or blunt cases, with a novel transition function. The second problem considered is that of scattering by thin shells of dielectric material. Under the assumption that the refractive index of the dielectric is large, approximate transition conditions for a layer of half a wavelength in thickness are formulated which account for the effects of curvature of the layer. Using these transition conditions the directivity of the fields scattered by a tightly curved tip region is determined, provided certain conditions are met by the tip curvature. In addition, creeping ray and whispering gallery modes outside such a curved layer are examined in the context of the GTD, and their initiation at a point of tangential incidence upon the layer is studied. The final problem considered concerns the scattering matrix of a closed convex body. A straightforward and explicit discussion of scattering theory is presented. Then the approximations of the GTD are used to find the first two terms in the asymptotic behaviour of the scattering phase, and the connection between the external scattering problem and the internal eigenvalue problem is discussed.
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Koen, Etienne. "A Simulation Approach to High-Frequency Plasma Waves." Licentiate thesis, KTH, Rymd- och plasmafysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-106822.

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Electrostatic waves in the form of Broadband Electrostatic Noise (BEN) have been observed in the Earth's auroral region associated with high geomagnetic activity. This broad frequency spectrum consists of three electrostatic modes, namely electron plasma, electron acoustic and beam-driven modes. These modes are excited in a plasma containing three electron components: hot, cool and beam electrons. A 1D Particle-in-Cell (PIC) simulation was developed to investigate the characteristics of the electrostatic waves found in such a plasma. Dispersion, phase space and spatial electric field diagrams were constructed from the output of the PIC simulation which were used to describe the wave dispersion and spatial field structures found in a plasma. The PIC code used a three electron component plasma with Maxwellian distributions to describe the electron velocity distributions. Beam-driven waves were found to dominate the frequency spectrum while electron plasma and electron acoustic waves are damped for a high beam velocity. Furthermore, for a high beam velocity, solitary waves are generated by electron holes (positive potentials), giving rise to a bipolar spatial electric fi eld structure moving in the direction of the beam. Increasing the beam temperature allows the beam electrons to mix more freely with the hot and cool electrons, which leads to electron plasma and electron acoustic waves being enhanced while beam-driven waves are damped. Decreasing the beam density and velocity leads to damping of beam-driven waves, while electron plasma and electron acoustic waves are enhanced. Measurements in Saturn's magnetosphere have found the co-existence of two electron (hot and cool) components. The electron velocities are best described by a kappa-distribution (instead of a Maxwellian) which has a high-energy tail. Using an adapted PIC simulation the study of electron plasma and electron acoustic waves was extended by using a kappa-distribution to describe the electron velocities with low indices. Electron acoustic waves are damped over most wave number ranges. Electron plasma waves are weakly damped at low wave numbers and damped for all other wave numbers.

QC 20121205

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Suedan, Gibreel A. "High frequency beam diffraction by apertures and reflectors." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27545.

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Most solutions for electromagnetic wave diffraction by obstacles and apertures assume plane wave incidence or omnidirectional local sources. Solutions to diffraction problems for local directive sources are needed. The complex source point representation of directive beams together with uniform solutions to high frequency diffraction problems is a powerful combination for this. Here the method is applied to beam diffraction by planar structures with edges, such as the half-plane, slit, strip, wedge and circular aperture. Previously used restrictions to very narrow beams and paraxial regions, are removed here and the range of validity increased. Also it is shown that the complex source point method can give a better approximation to broad antenna beams than the Gaussian function. The solution derived for the half-plane problem is uniform, accurate and valid for all beam orientations. This solution can be used as a reference solution for other uniform or asymptotic solutions and is used to solve for the wide slit and complementary strip problems. Uniform solutions for omidirectional sources are developed and extended analytically to become solutions for directive beams. The uniform theory of diffraction is used to obtain uniform solutions where there are no simple exact solutions, such as for the wedge and circular aperture. Otherwise rigorously correct solutions at high frequencies for singly diffracted far fields are used, such as for the half-plane, slit and strip. The geometrical theory of diffraction and equivalent line currents are used to include interaction between edges. Extensive numerical results including the limiting cases; e.g. plane wave incidence, line and point sources are given. These solutions are compared with previous solutions, wherever possible and good agreement is evident Beam diffraction by a wedge with its edge on the beam axis is analysed. This solution completes a previous asymptotic solution which is infinite on the shadow boundaries and inaccurate in the transition regions. Finally, the diffraction by a circular aperture illuminated by normally incident acoustic beam, is derived and the singularity along the axial caustic is removed using Bessel functions and a closed form expression for multiple diffraction is derived.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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Ford, E. A. K. "Gravity waves and small-scale structure of the high-latitude upper atmosphere." Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1445456/.

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Small-scale structure of the thermosphere is studied at high-latitudes for its important role in ion-neutral coupling. Four Fabry-Perot Interferometers (FPIs) in Scandinavia are primarily used. These are supplemented by a range of other instruments, including the Spectrograph Imaging Facility, radars, magnetometers, all-sky cameras, and satellite data. The FPIs measure the atomic oxygen emission line at 6300 A, from 240 km altitude. Emission intensities, thermospheric line of sight wind speeds, and neutral temperatures are obtained. Comparisons of electron densities from tomography data and EISCAT (European Incoherent SCATter) radar with FPI intensities allow the investigation whether dissociative recombination is the dominant production mechanisms of the nighttime 6300 A oxygen line. Cross correlations indicate that the thermosphere varies on short temporal scales. Altitude variations have less effect due to the broad (-50 km) emission height band. Atmospheric gravity waves in the thermosphere have been detected for the first time in ground-based FPI data using Lomb-Scargle analysis. Joule heating from electrojet currents, and particle precipitation in the auroral oval, have been identified as the primary source mechanisms using two case study nights. High time resolution data shows a limit to the variability of the thermosphere to be approximately 1-minute. Statistical studies of the gravity waves from 567 nights of FPI data show that the length of the night and time resolution are the most important influences on the number and periods of waves detected. Greater numbers of short period waves are detected in the rapidly responding intensities than in the winds and temperatures. Little variation with geomagnetic activity or solar cycle is observed. Periods at particular harmonics of the length of the night are preferred between October and February. Comparisons of mainland and Svalbard data show that the shorter period waves that are formed equatorward in the auroral oval mostly dissipate before reaching Svalbard.
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Al-Balushi, K. R. N. "The use of high frequency stress waves for monitoring gears." Thesis, Cranfield University, 1995. http://dspace.lib.cranfield.ac.uk/handle/1826/10575.

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The aim of this research is to investigate the feasibility of using stress waves for condition monitoring of gears. The project involved setting up an experimental rig, carrying out experimental work, acquiring stress waves signatures, and processing the signals. It has been shown that stress waves can successfully be employed for early detection of incipient gear failure. A experimental gearbox was employed during the experiments. Miniature ultrasound transducers, both sensitive and sufficiently small, were manufactured and installed on the stationary outer race of the rolling element bearing of the gearbox to detect stress waves from the meshing gears. The stress waves signals from the transducers were digitised and digitally processed to extract relevant information. The signatures were high-pass filtered at a cut-off frequency of 200 kHz, thus representing exclusive ultrasonic frequencies. A new statistical parameter, Energy Index, was developed and performed on the stress wave signatures which were segmented to represent individual gear teeth. Along with this new parameter, the classical statistical parameters, (Peaks, RMS, Standard Deviation, Kurtosis, etc.) were also performed. Conclusive results are presented in graphical form in terms of Cumulative Energy Indices' and Energy Indices in polar form for individual gear teeth. A new algorithrn was also developed and presented for the envelope detection of signal by iterative peak detection. Although no direct comparison was made between condition monitoring of gears using stress waves and methods such as low frequency vibration analysis and wear debris analysis, it is apparent that stress waves monitoring offers a much earlier warning of incipient gear failure because the technique can detect material defonnations which are precursors to changes in the dynamic properties of gears and the occurrence of wear debris. The technique, therefore, can predict incipient failure much earlier, extending the lead-time before failure, and as a result, minimising sudden failures which may have catastrophic consequences.
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Al-Balushi, Khamis Rajab Nasser. "The use of high frequency stress waves for monitoring gears." Thesis, Cranfield University, 1995. http://dspace.lib.cranfield.ac.uk/handle/1826/10575.

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The aim of this research is to investigate the feasibility of using stress waves for condition monitoring of gears. The project involved setting up an experimental rig, carrying out experimental work, acquiring stress waves signatures, and processing the signals. It has been shown that stress waves can successfully be employed for early detection of incipient gear failure. A experimental gearbox was employed during the experiments. Miniature ultrasound transducers, both sensitive and sufficiently small, were manufactured and installed on the stationary outer race of the rolling element bearing of the gearbox to detect stress waves from the meshing gears. The stress waves signals from the transducers were digitised and digitally processed to extract relevant information. The signatures were high-pass filtered at a cut-off frequency of 200 kHz, thus representing exclusive ultrasonic frequencies. A new statistical parameter, Energy Index, was developed and performed on the stress wave signatures which were segmented to represent individual gear teeth. Along with this new parameter, the classical statistical parameters, (Peaks, RMS, Standard Deviation, Kurtosis, etc.) were also performed. Conclusive results are presented in graphical form in terms of Cumulative Energy Indices' and Energy Indices in polar form for individual gear teeth. A new algorithrn was also developed and presented for the envelope detection of signal by iterative peak detection. Although no direct comparison was made between condition monitoring of gears using stress waves and methods such as low frequency vibration analysis and wear debris analysis, it is apparent that stress waves monitoring offers a much earlier warning of incipient gear failure because the technique can detect material defonnations which are precursors to changes in the dynamic properties of gears and the occurrence of wear debris. The technique, therefore, can predict incipient failure much earlier, extending the lead-time before failure, and as a result, minimising sudden failures which may have catastrophic consequences.
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Kipp, Robert. "Mixed potential integral equation solutions for layered media structures : high frequency interconnects and frequency selective surfaces /." Thesis, Connect to this title online; UW restricted, 1993. http://hdl.handle.net/1773/5974.

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Books on the topic "High frequency gravity waves"

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1943-, Varadan V. K., and Varadan V. V. 1948-, eds. Low and high frequency asymptotics. Amsterdam: North-Holland, 1986.

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High Frequency Ocean Acoustics Conference (2004 La Jolla, Calif.). High frequency ocean acoustics: High Frequency Ocean Acoustics Conference : La Jolla, California, 1-5 March, 2004. Edited by Porter Michael B, Siderius Martin, Kuperman William A, United States. Office of Naval Research., and Acoustical Society of America. Melville, N.Y: American Institute of Physics, 2004.

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D, Ivancic William, Zuzek John E, and United States. National Aeronautics and Space Administration., eds. Evaluation of components, subsystems, and networks for high rate, high frequency space communications. [Washington, DC]: National Aeronautics and Space Administration, 1991.

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High-frequency electromagnetic techniques: Recent advances and applications. New York: Wiley, 1995.

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F, Espinosa A., Geological Survey (U.S.), and U.S.-Spain Joint Committee for Scientific and Technological Cooperation., eds. Scattering and attenuation of high-frequency seismic waves: Development of the theory of coda waves. [Reston, Va.?]: Dept. of the Interior, U.S. Geological Survey, 1986.

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F, Espinosa A., Geological Survey (U.S.), and U.S.-Spain Joint Committee for Scientific and Technological Cooperation., eds. Scattering and attenuation of high-frequency seismic waves: Development of the theory of coda waves. [Reston, Va.?]: Dept. of the Interior, U.S. Geological Survey, 1986.

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C, Ferguson Dale, and United States. National Aeronautics and Space Administration., eds. Low frequency waves in the plasma environment around the shuttle. [Washington, DC: National Aeronautics and Space Administration, 1996.

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High Frequency Postgraduate Student Colloquium (4th 1999 Leeds, England). 1999 High Frequency Postgraduate Student Colloquium: The University of Leeds, 17 September, 1999. Piscataway, New Jersey: IEEE Service Center, 1999.

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High, Frequency Postgraduate Student Colloquium (5th 2000 Dublin Ireland). 2000 High Frequency Postgraduate Student Colloquium: University College Dublin, Ireland, 7-8 September, 2000. Piscataway, New Jersey: IEEE Computer Society, 2000.

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Alexander, M. J. The gravity wave response above deep convection in a squall line simulation. [Washington, DC: National Aeronautics and Space Administration, 1995.

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Book chapters on the topic "High frequency gravity waves"

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Kaboš, P., and V. S. Stalmachov. "High-Frequency MSW Elements." In Magnetostatic Waves and Their Application, 252–85. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1246-8_9.

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Gil’ denburg, V. B., I. S. Gushin, S. A. Dvinin, and A. V. Kim. "Dynamics of a High-Frequency Streamer." In Nonlinear Waves 3, 91–97. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-75308-4_8.

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Sato, Haruo, and Michael C. Fehler. "Attenuation of High-Frequency Seismic Waves." In Seismic Wave Propagation and Scattering in the Heterogeneous Earth, 109–48. New York, NY: Springer New York, 1998. http://dx.doi.org/10.1007/978-1-4612-2202-6_5.

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Sato, Haruo, and Michael C. Fehler. "Attenuation of High-Frequency Seismic Waves." In Seismic Wave Propagation and Scattering in the Heterogeneous Earth, 109–48. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-89623-4_5.

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Sato, Haruo, Michael C. Fehler, and Takuto Maeda. "Attenuation of High-Frequency Seismic Waves." In Seismic Wave Propagation and Scattering in the Heterogeneous Earth : Second Edition, 153–84. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-23029-5_5.

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Wang, Chi-Yuen, and Michael Manga. "Liquefaction." In Lecture Notes in Earth System Sciences, 301–21. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-64308-9_11.

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AbstractLiquefaction of the ground during earthquakes has long been documented and has drawn much attention from earthquake engineers because of its devastation to engineered structures. In this chapter we review a few of the best studied field cases and summarize insights from extensive experimental data critical for understanding the interaction between earthquakes and liquefaction. Despite the progress made in the last few decades, several outstanding problems remain unanswered. One is the mechanism for liquefaction beyond the near field, which has been abundantly documented in the field. This is not well understood because, according to laboratory data, liquefaction should occur only in the near field where the seismic energy density is great enough to cause undrained consolidation leading up to liquefaction. Another outstanding question is the dependence of liquefaction on the frequency of the seismic waves, where the current results from the field and laboratory studies are in conflict. Finally, while in most cases the liquefied sediments are sand or silty sand, well-graded gravel has increasingly been witnessed to liquefy during earthquakes and is not simply the result of entrainment by liquified sand. It is challenging to explain how pore pressure could build up in gravely soils and be maintained at a level high enough to cause liquefaction.
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Teshima, Koji. "High-Frequency Generation of High-Pressure Pulses Using a Diaphragmless Shock Tube." In Shock Waves @ Marseille I, 221–26. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-642-78829-1_35.

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Crighton, D. G., and P. Sionoid. "High Frequency Nonlinear Waves in Bubbly Liquid." In IUTAM Symposium on Waves in Liquid/Gas and Liquid/Vapour Two-Phase Systems, 127–36. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0057-1_10.

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Bystrov, S. A., E. N. Fomenko, F. V. Shugaev, and G. I. Shved. "Shock Wave Structure in a High-Frequency Discharge Plasma." In Shock Waves @ Marseille II, 391–94. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-642-78832-1_64.

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Remmler, Sebastian, Stefan Hickel, Mark D. Fruman, and Ulrich Achatz. "Direct Numerical Simulation of Breaking Atmospheric Gravity Waves." In High Performance Computing in Science and Engineering ‘14, 593–607. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-10810-0_39.

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Conference papers on the topic "High frequency gravity waves"

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Swenson, Gary, Jing Tang, Farzad Kamalabadi, and Steve Franke. "Methods of deducing intrinsic measurements of high frequency atmospheric gravity waves (AGWs)." In Remote Sensing, edited by Klaus Schäfer, Adolfo Comerón, James R. Slusser, Richard H. Picard, Michel R. Carleer, and Nicolaos I. Sifakis. SPIE, 2005. http://dx.doi.org/10.1117/12.626144.

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Hee, Jee Loong, Kathy Simmons, David Hann, and Michael Walsh. "Characterisation of Waves and Ligaments in Films Close to an Aeroengine Ball Bearing." In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-91698.

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Abstract Surface waves are observed in many situations including natural and engineering applications. Experiments conducted at the Gas Turbine and Transmissions Research Centre (G2TRC) used high speed imaging to observe multiscale wave structures close to an aeroengine ball bearing in a test rig. The dynamic behavior and scale of the waves indicate that these are shear-driven although highly influenced by gravity at low shaft speed. To understand the interactions between gas and liquid phases including momentum and mass transfers, characterization of the observed waves and ligaments was undertaken. Waves were studied at surfaces close to the ball bearing and ligaments were assessed near the cage. Characterization was in terms of frequency and wavelength as functions of speed, flow-rate, bearing axial load and gravity. The assessments confirmed the existence of gravity-capillary waves and capillary waves. Gravity-capillary waves were measured to have a longer mean wavelength on the co-current side of the bearing (gravity and shear acting together) compared to the counter-current side (gravity and shear opposing). Using a published definition of critical wavelength (λcrit), measured wavelengths at 3,000 rpm were 2.56λcrit on the co-current side compared to 1.86λcrit at the countercurrent location. As shaft speed increases, wavelength reduces with transition to capillary waves occurring at around 0.83λcrit. At shaft speeds beyond 5000 rpm, capillary waves were fully visible and the wavelength was obtained as 0.435λcrit. Flow-rate and load did not significantly influence wavelength. Wave frequency was found to be proportional to shaft speed. The gravity-capillary waves had frequencies within the range 13–25 Hz while capillary waves exhibited a frequency well beyond 100 Hz. The frequencies are highly fluctuating with no effect of load and flow rate observed. Ligaments were characterized using Weber number and Stability number. The number of ligaments increased with shaft speed. A correlation for ligament number based on operating conditions is proposed.
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Kim, Jang, Jaime Hui Choo Tan, Allan Magee, Guangyu Wu, Steve Paulson, and Bill Davies. "Analysis of Ringing Response of a Gravity Based Structure in Extreme Sea States." In ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/omae2013-11466.

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In designing fixed offshore platforms located in regions of severe wave conditions, the potential resonant response of the hull structure due to wave loads must be checked. Since the natural frequency of vibration of the hull structure is typically much higher than the dominant design wave frequency, conventional wave load analysis based on linear wave theory does not show dynamic amplification. However, it is known that steep waves are nonlinear and may contain significant energy at higher harmonics of the fundamental frequency. When the forcing frequency of the higher-harmonic wave load is close to the natural frequency of the structural vibration, a resonance i.e. ringing will occur and the structural dynamic response will be significantly amplified. This paper describes an analysis procedure to estimate high-frequency dynamic load on a Gravity Based Structure (GBS) exposed to severe sea states using Computational Fluid Dynamics (CFD) analysis and modal analysis. To fill the statistical gap between the extreme values from short-duration CFD-modal analysis and that from 3-hour design sea states, an approximation method has been developed to estimate the global dynamic load from the measured quasi-static load in earlier model test and to obtain a calibration factor for the CFD-modal analysis results.
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Beckwith, A. W., and Mohamed S. El-Genk. "Symmetries in Evolving Space-time and Their Connection to High-Frequency Gravity Wave Production." In 008. AIP, 2008. http://dx.doi.org/10.1063/1.2844938.

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Murad, Paul, and Glen A. Robertson. "An Anzatz about Gravity, Cosmology, and the Pioneer Anomaly." In SPACE, PROPULSION & ENERGY SCIENCES INTERNATIONAL FORMUM SPESIF-2010: 14th Conference on Thermophysics Applications in Microgravity 7th Symposium on New Frontiers in Space Propulsion Sciences 2nd Symposium on Astrosociology 1st Symposium on High Frequency Gravitational Waves. AIP, 2010. http://dx.doi.org/10.1063/1.3326256.

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Li, Li, Shixiao Fu, and Runpei Li. "Dynamic Analysis of Aquaculture Fish Cages in Irregular Waves." In ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/omae2013-10052.

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The aquaculture fish cage encounters random waves in the open sea. Understandings of their dynamic behaviors are important for design of the deepwater fish cages. In this paper, the hydrodynamic responses of a gravity-typed fish cage in irregular waves are studied based on FEM and Morison equations. The floating collar and the bottom ring are modeled by beam elements. Net lines are modeled by truss elements. Hydrodynamic forces are calculated by a modified Morison equation taking the relative motion between the fluid and structure members into account. The displacement responses characters (time history and spectrum) of the fish cage floating collar in random waves are investigated. The response results show some similarities between fish cage in regular waves and irregular waves. Both rigid body motions and flexible structural deformations can be seen of the floating collar and the whole fish cage. The net volume changes with time in irregular wave and also high frequency responses caused by the structural deformation are observed.
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Sheikh, Rizwan, and Chris Swan. "The Interaction Between Steep Waves and a Vertical, Surface-Piercing Column." In ASME 2003 22nd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2003. http://dx.doi.org/10.1115/omae2003-37154.

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The paper describes new laboratory observations concerning the interaction between a series of steep incident waves and a vertical, surface-piercing, column. The motivation for the study arose as a result of wave impact damage sustained to the undersides of several concrete gravity-based structures in the northern North Sea. Earlier work, Swan et al. [1], demonstrated that in the case of multiple column structures, the individual diameters of which lie outside the typical (linear) diffraction regime, there exists a new and previously unexpected mechanism leading to the scattering of high-frequency waves. Although the implications of this effect was carefully documented, not least because it explained the occurrence of wave impacts in relatively moderate seas, its physical origins remained unclear. In particular, it was uncertain whether this type of scattering would be observed in the case of a single column, or whether it results from the transmission of wave modes trapped between the legs of a multiple column structure. In the case of a single column, if the diameter, D, is such that the flow lies within the drag-inertia regime, D/λ < 0.2, where λ is the corresponding wavelength, linear diffraction theory suggests there will be little or no scattered wave energy. The present laboratory observations demonstrate that this is not, in fact, the case. If the incident waves are steep, a strong and apparently localised interaction is clearly observed at the water surface. This, in turn, leads to the scattering of high-frequency waves. Although these waves are relatively small in amplitude, their subsequent interaction with other steep incident waves takes the form of a classic long-wave short-wave interaction and can produce a significant increase in the maximum crest elevation relative to those recorded in the absence of the structure. The present paper will demonstrate that the scattering of these high-frequency waves, and their subsequent nonlinear interaction with other incident waves, has significant implications for the specification of an effective air-gap and hence for the setting of deck elevations.
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Felber, Franklin, and Glen A. Robertson. "Test of Relativistic Gravity for Propulsion at the Large Hadron Collider." In SPACE, PROPULSION & ENERGY SCIENCES INTERNATIONAL FORMUM SPESIF-2010: 14th Conference on Thermophysics Applications in Microgravity 7th Symposium on New Frontiers in Space Propulsion Sciences 2nd Symposium on Astrosociology 1st Symposium on High Frequency Gravitational Waves. AIP, 2010. http://dx.doi.org/10.1063/1.3326253.

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Holloway, Madonna-Megara, and Glen A. Robertson. "A New Cosmological Model for Matter, Energy, Sound, the Origin of the Universe and Gravity." In SPACE, PROPULSION & ENERGY SCIENCES INTERNATIONAL FORMUM SPESIF-2010: 14th Conference on Thermophysics Applications in Microgravity 7th Symposium on New Frontiers in Space Propulsion Sciences 2nd Symposium on Astrosociology 1st Symposium on High Frequency Gravitational Waves. AIP, 2010. http://dx.doi.org/10.1063/1.3326278.

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Brandenburg, John, and Glen A. Robertson. "Quantum GEM Gravity Theory Based on Path Integrals and the Kursunologu-Brandenburg Hypothesis of Gamma Ray Bursters." In SPACE, PROPULSION & ENERGY SCIENCES INTERNATIONAL FORMUM SPESIF-2010: 14th Conference on Thermophysics Applications in Microgravity 7th Symposium on New Frontiers in Space Propulsion Sciences 2nd Symposium on Astrosociology 1st Symposium on High Frequency Gravitational Waves. AIP, 2010. http://dx.doi.org/10.1063/1.3326257.

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Reports on the topic "High frequency gravity waves"

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Kuo, S. P. Basis of Ionospheric Modification by High-Frequency Waves. Fort Belvoir, VA: Defense Technical Information Center, June 2007. http://dx.doi.org/10.21236/ada470291.

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Bell, T. F., U. S. Inan, M. K. Demirkol, M. W. Chevalier, and R. Moore. Very Low Frequency (VLF) Remote Sensing of Gravity Waves Generated by the Auroral Electrojet. Fort Belvoir, VA: Defense Technical Information Center, January 2002. http://dx.doi.org/10.21236/ada399159.

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Badiey, Mohsen. Fluctuations of Mid-to-High Frequency Acoustic Waves in Shallow Water. Fort Belvoir, VA: Defense Technical Information Center, September 2009. http://dx.doi.org/10.21236/ada531595.

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Badiey, Mohsen. Fluctuations of Mid-to-High Frequency Acoustic Waves in Shallow Water. Fort Belvoir, VA: Defense Technical Information Center, September 2007. http://dx.doi.org/10.21236/ada542659.

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Pepper, Michael. Single-Photon Detection Using High Frequency Acoustic Waves on GaAs/AlGaAs Heterostructures. Fort Belvoir, VA: Defense Technical Information Center, November 2007. http://dx.doi.org/10.21236/ada521514.

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Lavery, Andone C. Analysis of High-Frequency Broadband Acoustic Scattering from Non-Linear Internal Waves During SW06. Fort Belvoir, VA: Defense Technical Information Center, September 2009. http://dx.doi.org/10.21236/ada531378.

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Nicholls, David P. High-Order Numerical Methods for the Simulation of Linear and Nonlinear Waves: High-Frequency Radiation and Dynamic Stability. Office of Scientific and Technical Information (OSTI), April 2014. http://dx.doi.org/10.2172/1129414.

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Lavery, Andone C. Continued Analysis of High-Frequency Broadband Acoustic Scattering from Non-Linear Internal Waves during SW06. Fort Belvoir, VA: Defense Technical Information Center, September 2010. http://dx.doi.org/10.21236/ada542102.

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Vernon, Frank L., Robert J. Mellors, and David J. Thomson. Broadband Signal Enhancement of Seismic Array Data: Application to Long-Period Surface Waves & High Frequency Wavefields. Fort Belvoir, VA: Defense Technical Information Center, April 1998. http://dx.doi.org/10.21236/ada343629.

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Lavery, Andone C. High-Frequency Broadband Acoustic Scattering from Temperature and Salinity Microstructure: From Non-Linear Internal Waves to Estuarine Plumes. Fort Belvoir, VA: Defense Technical Information Center, September 2007. http://dx.doi.org/10.21236/ada541144.

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