Search results for "GEOM"
showing 10 items of 6506 documents
Growth and aging of proximal femoral bone - a study with women spanning three generations
2015
Abstract. Osteoporotic hip fracture is a serious clinical event associated with high morbidity and mortality. Understanding femoral growth patterns is important for promoting bone health in the young and preventing fractures in later life. In this study, growth patterns of areal bone mineral density (aBMD) and geometric properties of the proximal femur were measured by dual-energy X-ray absorptiometry (GE Lunar Prodigy, USA). They were studied in 251 girls from premenarche (11.2±0.7 yrs) to late adolescence (18.3±1.1 yrs), and compared to their premenopausal mothers (n=128, aged 44.9±4.1 yrs) and postmenopausal grandmothers (n=128, aged 70.0±6.3 yrs). Hip axis length (HAL) was the first to …
Noise Reduction and Gap Filling of fAPAR Time Series Using an Adapted Local Regression Filter
2014
Time series of remotely sensed data are an important source of information for understanding land cover dynamics. In particular, the fraction of absorbed photosynthetic active radiation (fAPAR) is a key variable in the assessment of vegetation primary production over time. However, the fAPAR series derived from polar orbit satellites are not continuous and consistent in space and time. Filtering methods are thus required to fill in gaps and produce high-quality time series. This study proposes an adapted (iteratively reweighted) local regression filter (LOESS) and performs a benchmarking intercomparison with four popular and generally applicable smoothing methods: Double Logistic (DLOG), sm…
Non-adiabatic vacuum induced berry phase
2016
We investigate quantum effects in geometric phases arising when a two-level system is interacting with a quantized electromagnetic field.
Non-linear analysis of plane steel prestressed truss in fire
2002
The concept of analysis of 2-D static loaded prestressed steel trusses till failure during fire using a modified method of forces is presented. Failure of steel trusses in fire is based on the criterion of stresses. Behaviour of steel is described by non-linear constitutive model (based on hypo-elastic Ramberg-Osgood formula and Dorn creep theory) and Plem proposition (for string). Both models are approximated in calculations by hyperbolic Norton-Bailey rule. Fire simulates thermal force as an action of high temperature that increases linearly up to some level. The complete formulation of this method is illustrated by the algorithm of model parameters identification. Analysis of results for…
On the CAT(0) dimension of 2-dimensional Bestvina-Brady groups
2002
Let K be a 2-dimensional finite flag complex. We study the CAT(0) dimension of the `Bestvina-Brady group', or `Artin kernel', Gamma_K. We show that Gamma_K has CAT(0) dimension 3 unless K admits a piecewise Euclidean metric of non-positive curvature. We give an example to show that this implication cannot be reversed. Different choices of K lead to examples where the CAT(0) dimension is 3, and either (i) the geometric dimension is 2, or (ii) the cohomological dimension is 2 and the geometric dimension is not known.
Numerical Magnitude Affects Accuracy but Not Precision of Temporal Judgments
2021
A Theory of Magnitude (ATOM) suggests that space, time, and quantities are processed through a generalized magnitude system. ATOM posits that task-irrelevant magnitudes interfere with the processing of task-relevant magnitudes as all the magnitudes are processed by a common system. Many behavioral and neuroimaging studies have found support in favor of a common magnitude processing system. However, it is largely unknown whether such cross-domain monotonic mapping arises from a change in the accuracy of the magnitude judgments or results from changes in precision of the processing of magnitude. Therefore, in the present study, we examined whether large numerical magnitude affects temporal ac…
Exploring Kaleidocycles with LUX
2019
Participants can experiment with building a series of dynamic linkages, mainly triangular and cubic kaleidocycles with the LUX construction system. In order to make the required movements with LUX, a new LUX module has been developed. The new module will be introduced in the workshop, and participants will be asked to assess the further educational, artistic and creative potentials this module offers to the LUX system. After the introductory activities, participants will experiment on how to study these topics in multidisciplinary settings by using LUX in the mathematics classroom. The workshop combines hands-on geometry learning with other subjects, like arts, engineering and design. peerR…
Pair interactions in online assessments of collaborative problem solving: case-based portraits
2018
This exploratory case study focuses on how pairs of students can build a shared understanding and acquire collaborative problem-solving (CPS) practices during an online assessment of CPS skills, which is seen in the context of the CPS construct, in a symmetrical and asymmetrical task type. Even though CPS is widely recognised as a core twenty-first-century competency, its nature is not yet well understood. Also, until recently, most of studies have focused on the individual’s solution to a problem or on the skills individuals bring into a problem-solving space. This study extends from an individual- to group-level focus in CPS, emphasising the role and quality of the social aspects in CPS p…
Optimal Spectral Wavelengths for Discriminating Orchard Species Using Multivariate Statistical Techniques
2019
Sustainable management of orchard fields requires detailed information about the tree types, which is a main component of precision agriculture programs. To this end, hyperspectral imagery can play a major role in orchard tree species mapping. Efficient use of hyperspectral data in combination with field measurements requires the development of optimized band selection strategies to separate tree species. In this study, field spectroscopy (350 to 2500 nm) was performed through scanning 165 spectral leaf samples of dominant orchard tree species (almond, walnut, and grape) in Chaharmahal va Bakhtiyari province, Iran. Two multivariable methods were employed to identify the optimum wavelengths:…
Surrogate-assisted multicriteria optimization: Complexities, prospective solutions, and business case
2017
Complexity in solving real-world multicriteria optimization problems often stems from the fact that complex, expensive, and/or time-consuming simulation tools or physical experiments are used to evaluate solutions to a problem. In such settings, it is common to use efficient computational models, often known as surrogates or metamodels, to approximate the outcome (objective or constraint function value) of a simulation or physical experiment. The presence of multiple objective functions poses an additional layer of complexity for surrogate-assisted optimization. For example, complexities may relate to the appropriate selection of metamodels for the individual objective functions, extensive …