Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 20 for “"rotation curves"”.
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Correcting the rotation curve of spiral galaxies for the non-circular motions induced by a bar
… is usually determined through the use of rotation curves. This determination relies on two key assumptions; that the gas moves on circular orbits and that this motion traces the underlying gravitational potential. In the case of barred spiral galaxies the first assumption is false as the …
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Analysis of SALT Fabry-Pérot medium resolution data
… s⁻¹. So, we computed the kinematic maps and the rotation curves of the three galaxies using DiskFit and ROTCUR. For NGC 7361 and NGC 7424 we compared the rotation curves derived by both methods. For NGC 7793 we were also able to compare our results with previous studies.
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Classification of end plate connections with application to gable frames
… this study. End plate connections whose moment-rotation curves are known arc classified on the basis of moments as FR (fully restrained) and PR (partially restrained) connections. Further, the connections are also classified by entering a plot with coordinates - Ratio of Moment at the connection …
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Distribution of baryonic and dark matter in spiral and irregular nearby galaxies
… mass models. For the kinematical data, we use rotation curves from the GHASP survey. For the photometry data, we use the luminosity profile of the mid-infrared W1 and W2 (3.4 and 4.6 µm) of WISE (Wide-field Infrared Survey Explorer), which probes the emission from the old stellar population. …
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Analysis of vacuum and argon gas fill data from the MiniCLEAN dark matter experiment
… many astronomical observations. The rotation curves of galaxies and galaxyclusters, for example, indicate the majority of mass in these structures is unseen. The existence of weakly-interacting massive particles (WIMPs) was proposed in the early 1980s to account for the anomalous …
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An experimental study on the cyclic behaviour of riveted stiffened seat angle connection with concrete encasement.
… connections were tested and hysteretic moment-rotation curves were obtained. Models previously developed by other researchers were verified and practical recommendations are presented.
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Damping and flexural properties of prestressed concrete members subjected to reversed cyclic loading
… An analytical method of obtaining moment - rotation curves for prestressed members, taking account of curvature concentration at the tension cracks, is presented in part three. The last part is a study of the response of an idealized prestressed concrete structure to a recorded earthquake …
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Point by point gain calibration of the Dark Matter Time Projection Chamber
… clusters, dark matter can now explain galactic rotation curves, the hierarchical structure of the universe, and the gravitational lensing of the bullet cluster. Nonetheless, the exact particulate nature of dark matter remains a mystery. The Dark Matter Time Projection Chamber (DMTPC) is a …
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Galaxy-Scale Signatures of Screened Modified Gravities
… screened modified gravity: 'upturns' in galaxy rotation curves and asymmetries in stellar streams. If a galaxy is partially screened, it will have a 'screening radius', within which the fifth force is suppressed. Outside the screening radius, the fifth force on a test particle will be …
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Hybrid mathematical and informational modeling of beam-to-column connections
… relationship of components. Lastly, the moment-rotation curves of the mathematical models are compared with those of experimental tests. In the case of a top-and-seat angle connection with double web angles, a pinched hysteretic response is predicted quite well by complete mechanical models, …
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Multi-messenger constraints and pressure from dark matter annihilation into electron-positron pairs
… electron-positron pairs may affect the observed rotation curve by a significant amount. The injection rate of this calculation is constrained by INTEGRAL, Fermi, and H.E.S.S. data. The pressure of the relativistic electron-positron gas is computed from the energy spectrum predicted by the …
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Gravitational lensing of quasars by edge-on spiral galaxies
… in analyzing CX2201. Plans to obtain detailed rotation curves for the lensing galaxy are also underway, and it is the hope that future investigators will come to a better understanding of CX2201's unique features.
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THE COVARIANT APPROACH TO SPACE TIMES ANDSOME EXTENDED THEORIES OF GRAVITY
… was proposed to explain the shape of galaxy rotation curves without imposing dark matter. From the geometric point of view it is shown that the field equations can be recast into Einstein's ones augmented by an arbitrary Codazzi tensor. This simplifies the search of solutions. A new …
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The Structure of Dark Matter Haloes in Cosmological Simulations
… Finally, we compare the circular velocity curves of the haloes simulated with galaxies to the rotation curves of observed galaxies, using the Universal Rotation Curve model.
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A Dark Matter line search using 3D-modeling of Cherenkov showers below 10 TeV with VERITAS
… that provide indirect evidence, like galactic rotation curves that show that the galaxies are rotating too fast to keep their constituent parts, and galaxy clusters that bends the light coming from behind-lying galaxies more than expected with respect to the mass that can be calculated from …
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Kinematics and Stellar Populations in Brightest Cluster Galaxies
… peak and the presence of cooling flows). Clear rotation curves were found for a number of BOGs. In particular, NGC6034 and NGC7768 are rapidly rotating (> 100 km s⁻1 as measured from their major axis spectra), indicating that it is unlikely that they formed through dissipationless mergers. …
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Finite Element and Probabilistic Analysis of Soft Tissue Structures of the Human Lumbar Spine
… of these models are typically based on torque rotation data from a single subject or the models use average properties reported in literature. However, experimental testing reports variation up to 40% in ligament stiffness and even greater variability for annulus fibrosis properties. …
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Interstellar turbulence driven by magneto-rotational instability
… and investigate the global action of the magneto-rotational instability (MRI) in galactic disks with the help of 3D global magneto-hydrodynamical (MHD) simulations. The calculations were done with the time-stepping ZEUS 3D code using massive parallelization. The alpha-Omega dynamo is known to be …
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HI survey of local group dwarf galaxies
… than previous interferometric HI studies. Rotation velocities are derived for each galaxy. For NGC 6822, the rotation curve probes the gravitational potential out to 5.8 kpc, ∼ 1 kpc further than existing measurements. The rotation curves of Sextans A and B decline in the outer regions and …
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Experimental assessment of the mechanical behavior of immersion joints and a seismic mitigation method in immersed tunnels
… compression-release curve and the bending moment-rotation curves with different levels of axial forces were obtained. Through the obtained load-deformation curves, both the axial stiffness and the flexural stiffness of the joint were derived for use in practice. During this testing cases, a …