Bulletin of the American Physical Society
2009 Joint Spring Meeting of the Ohio Sections of the APS and AAPT
Volume 54, Number 3
Friday–Saturday, April 24–25, 2009; Ada, Ohio
Session P1: Poster Session (4:30-6:00 pm) |
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Room: McIntosh Center Activities Room |
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P1.00001: Buck Creek River Flow Analysis Yasas Dhanapala, Elizabeth George, John Ritter Buck Creek flowing through Springfield Ohio has a number of low-head dams currently in place that cause safety issues and sometimes make it impossible for recreational boaters to pass through. The safety issues include the back eddies created by the dams that are known as drowning machines and the hydraulic jumps. In this study we are modeling the flow of Buck Creek using topographical and flow data provided by the Geology Department of Wittenberg University. The flow is analyzed using Hydraulic Engineering Center - River Analysis System software (HEC-RAS). As the first step a model of the river near Snyder Park has been created with the current structure in place for validation purposes. Afterwards the low-head dam is replaced with four drop structures with V-notch overflow gates. The river bed is altered to reflect plunge pools after each drop structure. This analysis will provide insight to how the flow is going to behave after the changes are made. In addition a sediment transport analysis is also being conducted to provide information about the stability of these structures. [Preview Abstract] |
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P1.00002: Behavior of Particles in Circular Vortical Flow with Magnus Effect Eric Gossett In this presentation a phenomenological model of the behavior of hailstones in cyclonic storms is discussed. The equations of motion for the linearized case are solved using rotating frames of reference. [Preview Abstract] |
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P1.00003: Light Pipe Energy Savings Calculator Erin Owens, Ernest R. Behringer Dependence on fossil fuels is unsustainable and therefore a shift to renewable energy sources such as sunlight is required. Light pipes provide a way to utilize sunlight for interior lighting, and can reduce the need for fossil fuel-generated electrical energy. Because consumers considering light pipe installation may be more strongly motivated by cost considerations than by sustainability arguments, an easy means to examine the corresponding costs and benefits is needed to facilitate informed decision-making. The purpose of this American Physical Society Physics and Society Fellowship project is to create a Web-based calculator to allow users to quantify the possible cost savings for their specific light pipe application. Initial calculations show that the illumination provided by light pipes can replace electric light use during the day, and in many cases can supply greater illumination levels than those typically given by electric lighting. While the installation cost of a light pipe is significantly greater than the avoided cost of electricity over the lifetime of the light pipe at current prices, savings may be realized if electricity prices increase. [Preview Abstract] |
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P1.00004: A few remarks on The Length of Day: A Cosmological Perspective Vic Christianto, Matti Pitkaneny, Florentin Smarandache An interesting hypothesis concerning the varying length of day has been formulated in this edition, proposed by A. I. Arbab, based on a proposition of varying gravitational constant G. The main ideas are pointed out, and alternative frameworks are also discussed in particular with respect to the present common beliefs in astrophysics. Further observation is of course recommended in order to refute or verify this proposition. [Preview Abstract] |
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P1.00005: Arc Lamp Dose Development Using Mixture Designs Tom Coffey The US Department of energy estimates that 25\% of the commercial energy consumption and 12\% of residential energy consumption is used for lighting in the US. The under-lying science of ceramic metal halide lamps continues to elude complete understanding. Because modeling efforts give an incomplete picture, ceramic metal halide lamp design is largely an experimental science. Mixture designs are a special family of designed experiments used to determine the correct proportions of the components in a multi-component blend. The use of a mixture design to determine the dose composition for a ceramic metal halide arc lamp will be presented. [Preview Abstract] |
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P1.00006: Gas and Stellar Kinematics in the Giant Spiral Galaxy NGC 1961 Brian Sacash, Jason Pinkney Long-slit spectroscopy and CCD imaging from the Hubble Space Telescope and the MDM Observatory is presented for the massive spiral galaxy NGC 1961. We aimed to measure the mass of the central supermassive black hole (SMBH). We have developed our own software for spectral extraction and for the fitting of absorption and emission lines. The program subtracts the absorption-line (stellar) component from the emission-line spectra to improve the fidelity of our emission line measurements. We present our line centroids (velocities), widths (velocity dispersions), and strengths for the most prominent emission lines (H$\alpha $, [NII], and [SII]). The rotation curve from the ground-based data is in good agreement with previous work by Rubin (1979); its asymmetric appearance suggests a tidal interaction or merger. We use the rotation curve and surface photometry to estimate the enclosed mass profile of the galaxy. The emission lines near the nucleus broaden indicating more intrinsic dispersion than expected for a cold, gas disk. We estimate the BH mass using simple gas disk models. However, the high dispersion and the asymmetry in its inner rotation curve suggest that this approach is unreliable. [Preview Abstract] |
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P1.00007: Galaxy Properties and Substructure in the Cluster Abell 160 Craig Koontz, Jason Pinkney We have developed a procedure for building a large catalog of cluster galaxies and their photometric properties as measured with CCDs. Our first case, Abell 160, is relatively nearby and redshifts exist for its brightest galaxies. We have mosaiced this cluster in R and V filters using a CCD imager on the 1.3-meter McGraw-Hill telescope. We fitted a world coordinate system to the images using the software ``WCStools,'' then used ``Source Extractor'' to extract sources from the images. We have created software for merging catalogs in such a way as to avoid double counting, to reject cosmic rays, and to combine redundant measurements. The software also corrects magnitude differences by comparing the mean difference and adding this to each individual catalog before merging it to a master catalog. The measured properties included in this study were magnitude, ellipticity, position angle, size, and color (V-R). We investigate the efficacy of our separation of galaxies and stars and find that it begins breaking down around R=19.0. We divide our master catalog into several subsamples for substructure analysis. For one subsample, we attempt to separate cluster members from foreground and background galaxies using the color-magnitude relation. We compare the results of substructure diagnostics for the subsamples. In future work, we will examine correlation of substructure with galaxy properties (especially color, size and morphology). [Preview Abstract] |
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P1.00008: Gas and Stellar kinematics of late type spiral NGC 2976 James Gallagher, Jason Pinkney We present imaging and spectroscopy from ground and space-based observations of NGC 2976. This Sc galaxy has a small bulge and close proximity (only 3.6 Mpc) making it ideal for our search for small nuclear black holes (BH). Pre-existing information do not show it to have an AGN: {\it ROSAT} X-ray data do not show a nuclear point source, and it emits no radio jets. We confirm that N2976 has an HII type nuclear spectrum, consistent with intense star formation. {\it Keck} spectra reveal a stellar velocity dispersion of only $\sigma = 18-20$ km s$^{-1}$. The gas velocity dispersion is also about 20 km s$^{-1}$. {\it HST} imaging reveals an unusual nuclear double peak whose dominance flips going from the medium band (F547M) image to the narrow band (H$\alpha$) image. The emission line spectra do not show a regular rotation curve, despite an almost disk-like appearance of the extended H$\alpha$ emission. The M$_{BH} - \sigma$ relation predicts a BH mass of only 5$\times 10^4 M_{\odot}$. The virial theorem applied to the central gas blob gives a considerably larger upper limit ($\sim 10^6 M_{\odot}$). This appears to be another ``nucleus in formation", and may not have a supermassive BH at all, like M33. [Preview Abstract] |
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P1.00009: Hubble Redshift, Explained in both a Static Universe and an Expanding/Compressing Universe Dmitri Rabounski In my recent study (2009 APS April Meeting; Progress in Phys., 1/2009), I showed that a photon loses energy with distance due to the work done against the non-holonomity/rotation field of the isotropic space (photon home space, rotating with the velocity of light). This is due to the solution E=E$_{0}$exp(-H$^{2}$AT/c) for the scalar geodesic equation of a photon (the equation of energy), where deformation of space is neglected (a static universe). Here H is the angular velocity of the isotropic space (equal to the Hubble constant H$_{0}$=c/A), A is the radius of the Universe, T=L/c is the time of the photon's travel. The resulting redshift z=exp(H$_{0}$L/c)- (z$\approx $H$_{0}$/c at small distances) matches the observed Hubble law. Now I obtain the respective solutions in a deforming universe. The solutions reveal: 1) in an expanding unverse the redshift increases faster with distance than in a static case; 2) in a compressing universe the blueshift increases with distance slower than the redshift due to the space non-holonomity, so the blueshift changes to the redshift at a large distance compared to the radius of the Universe. The results have been presented in detail in Zelmanov Journal, v.2, 2009. [Preview Abstract] |
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P1.00010: Study of Pulsation Properties of LPVs in NGC 6553 Elisabeth Kager, Andrew Layden Long period variable stars (LPVs) are red giants or supergiants that vary in brightness as they pulsate radially. Their periods range from months to several years, and amplitudes can be many magnitudes. Studying these pulsation properties of LPVs as a function of position on the giant branch helps to constrain models of stellar structure, evolution, and pulsation. Studying LPVs in environments with known metallicity, age, and distance allows us to control these variables; globular clusters are an excellent environment. This study targets the metal-rich ([Fe/H] = -0.2), globular NGC 6553. We have acquired a time sequence of images using the CTIO 0.9-m telescope, and are gathering more data with the 0.4-m PROMPT telescope. We herein present our experimental methods and goals for the project. [Preview Abstract] |
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P1.00011: Computer Simulation Studies of Gramicidin Channel Hyundeok Song, Thomas Beck Ion channels are large membrane proteins, and their function is to facilitate the passage of ions across biological membranes. Recently, Dr. John Cuppoletti's group at UC showed that the gramicidin channel could function at high temperatures (360 -- 390K) with significant currents. This finding may have large implications for fuel cell technology. In this project, we will examine the experimental system by computer simulation. We will investigate how the temperature affects the current and differences in magnitude of the currents between two forms of Gramicidin, A and D. This research will help to elucidate the underlying molecular mechanism in this promising new technology. [Preview Abstract] |
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P1.00012: Intraglottal Pressure Distributions for Divergent Angles Jun Li This research studies asymmetric vocal fold oscillations. This kind of oscillation is well known in normal and pathological voices, such as unilateral paralysis, arytenoid fixation and webbing. The research is quite relevant to aerodynamics, however, the driving aerodynamics is relatively poorly known, and has been oversimplified in previous studies. Thus, there is a need for empirical work for this research. The current work is based on the intraglottal pressures for divergentl conditions. It also contains static models for intricate pressure measurements. [Preview Abstract] |
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P1.00013: Effect of PbSe nanoparticle inclusion on the lattice thermal conductivity of PbTe Diego Hernandez, Jeffrey Dyck, Yixin Zhao, Clemens Burda Thermoelectric materials are able to convert heat energy into electrical energy and vice versa. One route toward increasing thermoelectric efficiency is by creating nanometer-sized inclusions in traditional thermoelectric materials that would scatter acoustic phonons, which transmit thermal energy, more strongly than free charge carriers. For this study, pellets of bulk, polycrystalline lead telluride with varying concentrations of PbSe nanoparticle additives were prepared by pressing mixed powders. Measurements of electrical resistivity, thermal conductivity, and Seebeck coefficient were performed from 10 K to 300 K. Experimental thermal conductivity data were compared to a model of the lattice thermal conductivity based on Debye theory. The model takes into account grain boundary, phonon-phonon, and point defect scattering. The theoretical analysis reveals that the additional phonon scattering due to PbSe nanoparticles can be reasonably modeled as an increase in point defects. Further improvements to the model that more accurately represent the spatial extent of the nanoparticles will be discussed. The impact of the addition of PbSe nanoparticles on the electrical transport properties will also be presented. [Preview Abstract] |
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P1.00014: Three-layer Hall model analysis of Hall measurements from AlGaN layers Mo Ahoujja, S. Elhamri Temperature dependent Hall Effect measurements were performed on Si doped AlGaN layers before and after irradiation with 1 MeV electrons. Unlike GaN samples, a reliable two-donor fit could not be obtained for any of the investigated AlGaN samples, whether they were irradiated or unirradiated. It may be that for these samples, the two layer analysis is inadequate to yield the precise bulk carrier concentration and mobility. [Preview Abstract] |
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P1.00015: The effect of the electron scattering phase shifts upon the computational outcomes of the Low-Energy Electron Diffraction technique Sonya Adas, Lisa Meyers, Mellita Caragiu In a typical Low-Energy Electron Diffraction (LEED) investigation of a crystal surface, the electrons probing the surface are scattered by the atoms in the sample. The scattering process introduces phase shifts in the waves associated to the incoming electrons. An investigation of how these phase shifts influence the results of a LEED calculation are presented for the fairly complicated Cu(511) stepped surface. The phase shifts have been calculated using the Barbieri/Van Hove Phase Shift Package. The phase shifts considered correspond to copper atoms arranged in various planes of the copper crystal: (100), (111), and a close approximation of the (511) plane. [Preview Abstract] |
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P1.00016: Monte Carlo simulations to study the effect of chain stiffness on static and dynamic properties of polymer melts Kiran Khanal, Jutta Luettmer-Strathmann Static and dynamic properties of polymers are affected by the stiffness of the chains. In this work, we investigate structural and thermodynamic properties of a lattice model for semiflexible polymer chains. The model is an extension of Shaffer's bond- fluctuation model and includes attractive interactions between monomers and an adjustable bending penalty that determines the Kuhn segment length. This allows us to model melts of flexible and semiflexible chains. For this work, we performed Monte Carlo simulations for polymer melts with a range of bending parameters and densities. Results for chain dimensions show that the Kuhn segment length increases monotonously with the bending penalty and has a linear dependence for a range of bending parameters. Results for self diffusion constants show that the translational mobility is strongly reduced by increasing chain stiffness. We also investigate equation-of-state properties of the melts. [Preview Abstract] |
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P1.00017: Improving Debye Scattering Calculation Time via Parallel Processing Alex Mach, Eric Mandell In today's world of ever increasing program execution intensity there is a need to find faster ways of processing information, often accomplished by switching to a multi-core or multi-CPU computer system. An example of a calculation that can transparently benefit is that of either x-ray or electron diffraction data, using an equation written by Debye. One problematic aspect of this calculation is that as the number of atoms in the atomic model increases, the time it takes to calculate the profile increases significantly. While this is normally not a problem when analyzing single crystals, it may be advantageous to some researchers to calculate data for a model that has nearly the same number of atoms as expected to contribute to x-ray or electron diffraction in experimental data (on the order of say 100,000 atoms). A model on this scale might examine subtle features in diffraction profiles, due to recurring relationships between adjacent crystals in a bulk material (i.e. faceting between graphene sheets). Here, improvements in calculation time are measured and compared for a single processor, a multi-CPU system, and a multi-core system using the Debye equation. We also examine differences between the multi-CPU and multi-core platforms. [Preview Abstract] |
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P1.00018: Student perceptions of WebCT in algebra-based physics Maria Cristina Sheridan Students in a traditional algebra-based physics lecture were exposed over the course of the three quarter sequence to three methods of delivering supplementary class material: paper handouts, access through the campus network, and WebCT. Results of a student survey on their perceptions of the three methods will be presented. [Preview Abstract] |
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P1.00019: Charge fluctuations of particles on surfaces exposed to plasma T.E. Sheridan A stochastic model for charge fluctuations on a microscopic dust particle resting on a surface exposed to plasma is presented. We assume that the ion flux to the particle is independent of its potential, while the electron flux depends on potential through the Boltzmann relation. The standard deviation of the particle charge is found to scale as $\sqrt{CT_{e}}$, where $C$ is the particle-surface capacitance and $T_{e}$ is the plasma electron temperature. The charging time, as found from Monte Carlo calculations, scales linearly with $CT_{e}$. [Preview Abstract] |
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P1.00020: Measurements of Finite Dust Temperature Effects in the Dispersion Relation of the Dust Acoustic Wave Erica Snipes, Jeremiah Williams A dusty plasma is a four-component system composed of ions, electrons, neutral particles and charged microparticles. The presence of these charged microparticles gives rise to new plasma wave modes, including the dust acoustic wave. Recent measurements [1, 2] of the dispersion relationship for the dust acoustic wave in a glow discharge have shown that finite temperature effects are observed at higher values of neutral pressure. Other work [3] has shown that these effects are not observed at lower values of neutral pressure. We present the results of ongoing work examining finite temperature effects in the dispersion relation as a function of neutral pressure. \\[4pt] [1] E. Thomas, Jr., R. Fisher, and R. L. Merlino, Phys. Plasmas 14, 123701 (2007). \\[0pt] [2] J. D. Williams, E. Thomas Jr., and L. Marcus, Phys. Plasmas 15, 043704 (2008). \\[0pt] [3] T. Trottenberg, D. Block, and A. Piel, Phys. Plasmas 13, 042105 (2006). [Preview Abstract] |
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P1.00021: The fusion/plasma physics chart from CPEP Gordon Aubrecht The Contemporary Physics Education Project has created charts and support for teachers for particle physics, cosmology, nuclear physics, and plasma physics. This poster shows and gives some background on our fusion / plasma physics chart. [Preview Abstract] |
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P1.00022: Changing the coupling in a class of two field fluid models Andrew Foster, Cavendish McKay In fluid dynamics problems, including those arising in plasma physics, it is not uncommon to have nonlinearly coupled systems of field equations. We examine a class of these systems for which a change of basis shifts the coupling out of the nonlinearity and into the associated elliptic problem. We will illustrate and interpret this change of basis in two specific examples: a two layer quasigeostrophic ocean model, and a modified form of reduced MHD. The main motivation for this change of basis is to improve computational efficiency, but it can also lead to significant physical insights. [Preview Abstract] |
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P1.00023: Measurement of the Dynamics of Tippe Tops Kelsie McCartney, Craig Howald We examine experimentally the motion of Tippe tops: tops with spherical shape symmetry, but only axial mass symmetry. Tippe tops with sufficient initial spin invert, raising their center of mass because of the action of friction. Video analysis is used to explore the dynamics of this inversion and its dependence on top parameters and initial conditions. [Preview Abstract] |
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P1.00024: Achieving Nanosecond Timing with the Vernier Method Rebecca Cooper, Elizabeth George, Paul Voytas Many subatomic processes occur in a small time frame, on the order of nanoseconds. We report on a project to create a circuit that can measure time intervals accurately on a nanosecond scale. To achieve this we used the vernier method which is based on coincidence between two oscillators of slightly different frequencies. For accurate timing, the oscillators needed to have a stable, clean signal. The frequency needed to be in the MHz range, producing a pulse period of $\sim $100 ns, and the pulse width needed to be as narrow as possible, on the order of a few nanoseconds. Relaxation oscillators based on unbuffered inverters in an RC circuit were used to generate the pulses. To shorten the pulses, we used a high-speed comparator circuit that created two pulses from the input pulse, one of which was inverted and delayed relative to the other, and an AND gate that combined the two, thus creating a shorter pulse. We have achieved a frequency of 4.5 MHz and a width of 8 ns. [Preview Abstract] |
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P1.00025: Positional Dependent Driving Torque in the Damped, Driven Pendulum Todd McAlpine, Alison Huff We investigate the dynamics of a plane pendulum with positional dependent driving torque as would be produced by a horizontally directed force exerted on the pendulum bob. We compare this with the well known dynamics of a standard damped, driven plane pendulum. In particular we compare the bifurcation diagrams of the two systems to compare the effects of the driving amplitude on the dynamics. In the system with positional dependent driving torque, bifurcation begins at higher driving amplitudes and there is a repetitive structure in the bifurcation diagram at high driving amplitude. Additionally, with positional dependent driving torque we see continued chaotic behavior at high driving amplitude whereas the chaotic behavior of the standard pendulum dies out at large driving amplitudes. [Preview Abstract] |
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P1.00026: Upper Limit of Mendeleev's Periodic Table of Elements -- Element No.155 Albert Khazan The most important problem for the scientists, who are working on the theory of Mendeleev's Periodic Table, is how to determine the real number of elements in it. One of the mainstream methods applied to resolving this problem suggests a calculation for the stability limits of the electronic shells of atoms. In this way, one sets up a number of elements for a period of the Table, and then calculates (as a sequence) the respective atomic masses for the elements. A second mainstream way is synthesis of new elements in nuclear reactions, with identification of the obtained products among which a new element may be found (meanwhile the element may unnecessary be the last). 10 new elements were obtained in this way during the last 25 years. In contrast, the basis of my calculation were neither calculations for the stability limits of the atomic shells nor synthesis of new elements, but a study of chemical processes which allowed, through the mathematical apparatus, to formulate a new law of Hyperbolas in the Periodic Table, and led to the last element No.155 whose atomic mass is 411.66 (details in: Khazan A. Progress in Physics, 2007, v.1, 38; v.2, 83, 104; 2008, v.3, 56; 2009, v.2, 19, L12). [Preview Abstract] |
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P1.00027: Haunted Quantum Entanglement Douglas Snyder There are two steps in establishing a quantum entanglement. These two steps often are not considered as independent from one another. Step 1 involves the interaction through which the particles are to be entangled. Step 2 involves making the result of the interaction through which the development of the entanglement begins available to the environment. Step 1 can occur in isolation from the environment. Step 2 then occurs with making the result of the interaction available to the environment through no longer isolating the particles. The entanglement that begins to develop in step 1 can originate in a form where there is which-way information. With step 2, the entanglement is complete and which-way information is established (option 1). Instead of completing the entanglement with step 2, the developing entanglement can be eliminated with the result that which-way information is lost. The result is a distribution for each of the paired particles that exhibits interference (option 2). The elimination of the developing entanglement results in haunted quantum entanglement. Through the use of options 1 and 2, one need not associate measurements on each of two entangled particles after measurements on each of the particles in order to decipher information. Associating measurements can be done automatically as measurements are made through the ability to control whether a developing entanglement is allowed to be fully established or instead eliminated. Options 1 and 2 can be used in a communications device. [Preview Abstract] |
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P1.00028: Locomotion Speeds of Various Dinosaurs M.T. Dougherty, S.A. Lee A methodology for estimating the locomotion speed of an animal based upon their footprint tracks is developed. Using this technique, an analysis of the locomotion speeds of various dinosaurs is performed. The tracks studied include 28 theropods (meat-eating dinosaurs), 23 sauropods (the ``long-necked'' herbivores), 28 non-armored, non-sauropod herbivores and 10 armored, non-sauropod herbivores. The theropods show the fastest locomotion speed as well as the greatest variety of speeds while the armored dinosaurs are the slowest. [Preview Abstract] |
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