578 research outputs found
Proving our point: the need for valid and reliable measures of diabetes education
No Abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77516/1/1489_ftp.pd
Assessment of Pile Group Response under Lateral Load
Assessment of the response of a laterally loaded pile group based on soil-pile interaction is presented in this paper. The behavior of a pile group in uniform and layered soil (sand and/or clay) is predicted based on the strain wedge (SW) model approach that has been developed to predict the response of a flexible pile under lateral loading. The pile group is characterized in terms of three-dimensional soil-pile interaction and then transformed into its one-dimensional beam on elastic foundation equivalent with associated parameters (modulus of sugrade reaction). Therefore, the interference among the piles in a group is determined based on the geometry of the mobilized passive wedge of soil in front of the pile in addition to the pile spacing. The overlap of shear zones among the piles in the group varies along the length of the pile and changes from one soil to another in the soil profile. Also, the interference among the piles grows with the increase in lateral loading. The modulus of subgrade reaction determined will account for the additional strains (i.e. stresses) in the adjacent soil due to pile interference within the group
Effect of the Non-Linear Behavior of Pile Material on the Response of Laterally Loaded Piles
The main purpose of this study is to assess the lateral response of piles/shafts and the p-y curves for different soil-pile combinations while introducing the effect of the moment-curvature (M - Φ) relationship of the pile into the soil-pile interaction. Therefore, the equilibrium among soil reaction, pile deflection pattern, pile-head load, and flexural stiffness distribution should be satisfied at any level of loading. The influence of the nonlinear behavior of the pile/drilled shaft material on the nature of the associated p-y curve is presented through strain wedge (SW) model analysis. The SW model allows the assessment of the (soil-pile) modulus of subgrade reaction (i.e. the p-y curve) based on soil and pile properties which includes the pile bending stiffness. Therefore, the assessed modulus of subgrade reaction will be affected by changes in the bending stiffness of the pile or drilled shaft at any pile cross section (via the M-Q relationship). The reduction in pile bending stiffness will affect the pile-head stiffness under varying static or dynamic loading
Confirming the intrinsic abundance spread in the globular cluster NGC 6273 (M19) with calcium triplet spectroscopy
We present metallicities for red giant stars in the globular cluster NGC 6273 based on intermediate resolution GMOS-S spectra of the calcium triplet region. For the 42 radial velocity members with reliable calcium triplet line strength measurements, we obtain metallicities, [Fe/H], using calibrations established from standard globular clusters. We confirm the presence of an intrinsic abundance dispersion identified by Johnson et al. (2015). The total range in [Fe/H] is ∼1.0 dex and after taking into account the measurement errors, the intrinsic abundance dispersion is σint[Fe/H] = 0.17 dex. Among the Galactic globular clusters, the abundance dispersion in NGC 6273 is only exceeded by ω Cen, which is regarded as the remnant of a disrupted dwarf galaxy, and M 54, which is the nuclear star cluster of the Sagittarius dwarf galaxy. If these three globular clusters share the same formation mechanism, then NGC 6273 may also be the remnant nucleus of a disrupted dwarf galaxy
Displacement Based Design of Retaining Walls
A relatively simple rigid plastic model to study deformation behavior of rigid retaining wall is outlined. Both sliding and tilting modes of deformation are included. The study clearly reveals that wall movement caused by tilting can be substantial. But for high values of foundation soil friction angle, the tilting component of deformation can be omitted. Since the wall movement is affected by the characteristics (strength and frequency) of the excitation history, a number of excitation histories should be considered in retaining wall designs
Dynamic Modeling of Layered Systems to Moving Surface Loads: Applications
Two important application of a recently developed moving load model are described. The model uses an efficient semi analytical finite layer formulation of the porous medium. One application is a response of a layered sandy nonlinear porous medium, while the other is a viscoelastic pavement layer system. The study reveals that the properties of the layers and porefluid and the moving velocity of the load are important factors that affect the response of the layered system
Combining continuous near–road monitoring and inverse modeling to isolate the effect of highway expansion on a school in Las Vegas
AbstractThe impact of a highway expansion on a school adjacent to the highway is investigated with a novel method called the Sustained Wind Incidence Method (SWIM). SWIM falls under the broad group of environmental forensics methods where measured concentration data are used to identify possible contributors such as a point, line or a sectional source. SWIM helps to identify potential sources by highlighting spatial domains associated with the markers unique to potential contributors. In this study, SWIM is used to identify sources of traffic related emissions. The marker used to measure the impact of the traffic due to expansion is black carbon (BC), a key traffic related emission mostly associated with large vehicles (>12m in length), collected both before and after the expanded lanes were open for use. Using this method, multiple source domains may be simultaneously identified. For this study, the data collection site was situated at the school about 20 meters from the sound wall (7 meters high) separating the school and the highway. SWIM results show that the road expansions may have impacted the traffic patterns of the nearby non–highway feeder road and on–ramp (adjacent to the sound wall) traffic to the highway. This sector showed a surprisingly larger change than the highway in the observed increase in their relative contribution to the receptor site. Some domains (apportioned sector) show a dramatic increase ranging roughly from 10% to 50% in relative contributions. Using the output from SWIM and knowledge of local contributors, a local source landscape is painted
Identifying complex sources in large astronomical data using a coarse-grained complexity measure
The volume of data that will be produced by the next generation of
astrophysical instruments represents a significant opportunity for making
unplanned and unexpected discoveries. Conversely, finding unexpected objects or
phenomena within such large volumes of data presents a challenge that may best
be solved using computational and statistical approaches. We present the
application of a coarse-grained complexity measure for identifying interesting
observations in large astronomical data sets. This measure, which has been
termed apparent complexity, has been shown to model human intuition and
perceptions of complexity. Apparent complexity is computationally efficient to
derive and can be used to segment and identify interesting observations in very
large data sets based on their morphological complexity. We show, using data
from the Australia Telescope Large Area Survey, that apparent complexity can be
combined with clustering methods to provide an automated process for
distinguishing between images of galaxies which have been classified as having
simple and complex morphologies. The approach generalizes well when applied to
new data after being calibrated on a smaller data set, where it performs better
than tested classification methods using pixel data. This generalizability
positions apparent complexity as a suitable machine-learning feature for
identifying complex observations with unanticipated features.Comment: 15 pages, 8 figures. New version to match that appearing in the
journal. Appearing in PASP Focus on Machine Intelligence in Astronomy and
Astrophysic
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