2,182 research outputs found
Fusing airborne laser scanner data and aerial imagery for the automatic extraction of buildings in densely built-up areas
Automated delineation of roof planes from LIDAR data
In this paper, we describe an algorithm for roof line delineation from LIDAR data which aims at achieving models of a high level of detail. Roof planes are initially extracted by segmentation based on the local homogeneity of surface normal vectors of a digital surface model (DSM). A case analysis then reveals which of these roof planes intersect and which of them are separated by a step edge. The positions of the step edges are determined precisely by a new algorithm taking into account domain specific information. Finally, all step edges and intersection lines are combined to form consistent polyhedral models. In all phases of this workflow, decision making is based upon statistical reasoning about geometrical relations between neighbouring entities in order to reduce the number of control parameters and to increase the robustness of the method
Evaluation of a method for fusing LIDAR data and multispectral images for building detection
In this paper, we describe the evaluation of a method for building detection by the Dempster-Shafer fusion of LIDAR data and multispectral images. For that purpose, ground truth was digitised for two test sites with quite different characteristics. Using these data sets, the heuristic model for the probability mass assignments of the method is validated, and rules for the tuning of the parameters of this model are discussed. Further we evaluate the contributions of the individual cues used in the classification process to the quality of the classification results. Our results show the degree to which the overall correctness of the results can be improved by fusing LIDAR data with multispectral images
Time decay of the remanent magnetization in the spin glass model at T=0
Using the zero-temperature Metropolis dynamics, the time decay of the
remanent magnetization in the Edward-Anderson spin glass model with a
uniform random distribution of ferromagnetic and antiferromagnetic interactions
has been investigated. Starting from the saturation, the magnetization per spin
reveals a slow decrease with time, which can be approximated by a power
law:, . Moreover, its
relaxation does not lead it into one of the ground states, and therefore the
system is trapped in metastable isoenergetic microstates remaining magnetized.
Such behaviour is discussed in terms of a random walk the system performs on
its available configuration space.Comment: 9 pages, 3 figure
A search for anomalously heavy isotopes of low Z nuclei
We present preliminary results of a search for anomalously heavy isotopes of certain light elements using an electrostatic charged particle spectrometer in conjunction with the MP tandem accelerator facility at the Nuclear Structure Research Laboratory of the University of Rochester. New limits for the existence of anomalous, heavy isotopes (100–10,000 amu) in ordinary, terrestrial Li, Be, B and F samples and enriched H2, C13, and O18 samples are reported.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87394/2/1143_1.pd
SPT-3G: A Next-Generation Cosmic Microwave Background Polarization Experiment on the South Pole Telescope
We describe the design of a new polarization sensitive receiver, SPT-3G, for
the 10-meter South Pole Telescope (SPT). The SPT-3G receiver will deliver a
factor of ~20 improvement in mapping speed over the current receiver, SPTpol.
The sensitivity of the SPT-3G receiver will enable the advance from statistical
detection of B-mode polarization anisotropy power to high signal-to-noise
measurements of the individual modes, i.e., maps. This will lead to precise
(~0.06 eV) constraints on the sum of neutrino masses with the potential to
directly address the neutrino mass hierarchy. It will allow a separation of the
lensing and inflationary B-mode power spectra, improving constraints on the
amplitude and shape of the primordial signal, either through SPT-3G data alone
or in combination with BICEP-2/KECK, which is observing the same area of sky.
The measurement of small-scale temperature anisotropy will provide new
constraints on the epoch of reionization. Additional science from the SPT-3G
survey will be significantly enhanced by the synergy with the ongoing optical
Dark Energy Survey (DES), including: a 1% constraint on the bias of optical
tracers of large-scale structure, a measurement of the differential Doppler
signal from pairs of galaxy clusters that will test General Relativity on ~200
Mpc scales, and improved cosmological constraints from the abundance of
clusters of galaxies.Comment: 21 pages, 9 figures. To be published in Proceedings of SPIE Volume
9153. Presented at SPIE Astronomical Telescopes + Instrumentation 2014,
conference 915
Design and Bolometer Characterization of the SPT-3G First-year Focal Plane
During the austral summer of 2016-17, the third-generation camera, SPT-3G,
was installed on the South Pole Telescope, increasing the detector count in the
focal plane by an order of magnitude relative to the previous generation.
Designed to map the polarization of the cosmic microwave background, SPT-3G
contains ten 6-in-hexagonal modules of detectors, each with 269 trichroic and
dual-polarization pixels, read out using 68x frequency-domain multiplexing.
Here we discuss design, assembly, and layout of the modules, as well as early
performance characterization of the first-year array, including yield and
detector properties.Comment: Conference proceeding for Low Temperature Detectors 2017. Accepted
for publication: 27 August 201
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