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Showing 1 to 20 of 243 for “"Modal Analysis"”.
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Stereovision Correction Using Modal Analysis
… on a flying wing aircraft by the using a modal survey to understand its behavior. Finally, the flying wing aircraft is subjected to random excitation and a least square fit of the random excitation signal is used to determine points of maximum deflection suitable for stereo image …
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Modal analysis of laser vibrated structures
This thesis describes the laser irradiation of metallic structures to excite mechanical vibrations within those structures. As found by other authors, single high-power laser pulses ablate the irradiated surface material and may impulsively excite structural vibration; however, the use of laser …
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Parametric spatial modal analysis of beams
Modal analysis is the experimental characterization of the dynanlical behavior of a structure. Recent advances in laser velocimetery have made available to the experimentalist a rich, new source of vibration data. Data can now be obtained from many different spatial locations on a structure. A …
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System modeling and modification via modal analysis
… stiffness, and damping are convertible to global modal mass, stiffness, and damping through normal mode corrections. Then a physical space mathematical model may be assembled from the modal properties for complete and truncated modal vector system descriptions. Therefore, this method will deal …
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DMD and POD Modal Analysis for Store Separation
… data-set was then used to identify which modal method, POD or DMD, better resolves the known dominate structures of the flow field. The results of this analysis showed the superiority of POD in identifying both free-stream and surface pressure structures. A final representative case of …
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Modal analysis and control of flexible manipulator arms.
Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Mechanical Engineering.
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Modal analysis of a cylindrical dielectric-loaded cavity
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1987.
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Quantitative multi-modal analysis of pediatric focal epilepsy
… project is to provide an end-to-end quantitative analysis pipeline that fuses an array of imaging modalities including magnetic resonance imaging (MRI), diffusion tensor MRI, positron emission tomography (PET), single-photon emission computerized tomography (SPECT) as well as EEG data to build …
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Damage Detection in Aluminum Cylinders Using Modal Analysis
… variation include the error introduced by modal parameter extraction, measurement noise, and the mass loading of the accelerometer. Structure variability is due to slight differences in the supposedly identical structures. Dimensional tolerancing is one example. This study began with six …
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Modal Analysis of the Ice-Structure Interaction Problem
… contact at a specific vertical pier location. Modal analysis is used in which the response of each mode is superposed to find the full modal response of the entire length of a pier subject to incremental ice loading. This incremental ice loading includes ice fracture points as well as loss of …
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Modal Analysis Techniques in Wide-Area Frequency Monitoring Systems
… disturbances based on power system post-event modal properties. In this work, power system dynamics are examined from an internal system energy viewpoint. Since an electric power system is composed of coupled rotating machines (large generators) which have air gap magnetic fields that are …
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Modal Analysis of Millimetre-wave and Terahertz Imaging Systems
… modes have been frequently reported in the analysis of paraxial millimetre-wave propagation in astronomical optical systems. Here the method of Gaussian beam mode analysis (GBMA) is extended to fields of optical research that have until recently been associated with wavelengths in the …
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Selective modal analysis with applications to electric power systems
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1981.
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High-Resolution, High-Frequency Modal Analysis for Instrumented Buildings
… Often, the baseline is defined in terms of modal parameters: natural frequencies, damping ratios, and mode shapes. Although changes in modal parameters are indicative of structural damage, they are also indicative of a slew of non-damage factors, such as signal-to-noise ratio, environmental …
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Modal analysis of the PHALANX M61A1 close-in weapons system
A Modal analysis of a PHALANX gun assembly was conducted in the laboratory at Naval Postgraduate School. The goal of this analysis is to provide a dynamical description of the gun for studies of the effects of gun modifications on bullet dispersion. Accelerometer data were collected from five …
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Operational modal analysis and model updating with a cyclostationary input
… thesis addresses the problem of identifying the modal properties of a system based only on measurements of the system responses. This situation is frequently encountered in structural dynamics and is particularly relevant for systems where the in-service excitation is not artificially …
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Modal Analysis of Multistory Framed Structures Subjected to Earthquake Effects
Made available in DSpace on 2014-12-08T23:56:32Z (GMT). No. of bitstreams: 1 6607722.pdf: 4412833 bytes, checksum: d25596956840d371524ac4708e54b09a (MD5) Previous issue date: 1966
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Investigating Various Modal Analysis Extraction Techniques to Estimate Damping Ratio
… have devoted their work to the development of modal analysis extraction techniques in order to obtain more reliable identification of the modal parameters. Also, as a consequence of all this work, there are some other works devoted to the evaluation and comparison of these methods in order to …
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Computational Modal Analysis of Prestressed Half Scale Generic Business Jet Substructures
Computational modal analysis via finite element analysis is a well-established method for modal parameter estimation. The resultant modal parameters are crucial inputs for vibro-acoustic finite element analyses and require accurate modal models. The work presented here aims to provide insight into …
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Acoustic emission source location in composite aircraft structures using modal analysis
… AE wave by a combination of time of arrival and modal analysis. The small footprint of the array allows for a fast and easy installation in hard-to-reach areas. The possibility to locate damage outside and at a relatively far distance from the array could potentially reduce the overall number of …
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