1,416 research outputs found
Description and capabilities of a traveling wave sonic boom simulator
Description and capabilities of traveling wave sonic boom simulator
ARGG-HDL: A High Level Python Based Object-Oriented HDL Framework
We present a High-Level Python-based Hardware Description Language
(ARGG-HDL), It uses Python as its source language and converts it to standard
VHDL. Compared to other approaches of building converters from a high-level
programming language into a hardware description language, this new approach
aims to maintain an object-oriented paradigm throughout the entire process.
Instead of removing all the high-level features from Python to make it into an
HDL, this approach goes the opposite way. It tries to show how certain features
from a high-level language can be implemented in an HDL, providing the
corresponding benefits of high-level programming for the user
Magnetic properties of a capped kagome molecule with 60 quantum spins
We compute ground-state properties of the isotropic, antiferromagnetic
Heisenberg model on the sodalite cage geometry. This is a 60-spin spherical
molecule with 24 vertex-sharing tetrahedra which can be regarded as a molecular
analogue of a capped kagome lattice and which has been synthesized with
high-spin rare-earth atoms. Here, we focus on the case where quantum
effects are strongest. We employ the SU(2)-symmetric density-matrix
renormalization group (DMRG).
We find a threefold degenerate ground state that breaks the spatial symmetry
and that splits up the molecule into three large parts which are almost
decoupled from each other. This stands in sharp contrast to the behaviour of
most known spherical molecules. On a methodological level, the disconnection
leads to "glassy dynamics" within the DMRG that cannot be targeted via standard
techniques.
In the presence of finite magnetic fields, we find broad magnetization
plateaus at 4/5, 3/5, and 1/5 of the saturation, which one can understand in
terms of localized magnons, singlets, and doublets which are again nearly
decoupled from each other. At the saturation field, the zero-point entropy is
in units of the Boltzmann constant
Performance of the EUDET-type beam telescopes
Test beam measurements at the test beam facilities of DESY have been
conducted to characterise the performance of the EUDET-type beam telescopes
originally developed within the EUDET project. The beam telescopes are equipped
with six sensor planes using MIMOSA26 monolithic active pixel devices. A
programmable Trigger Logic Unit provides trigger logic and time stamp
information on particle passage. Both data acquisition framework and offline
reconstruction software packages are available. User devices are easily
integrable into the data acquisition framework via predefined interfaces.
The biased residual distribution is studied as a function of the beam energy,
plane spacing and sensor threshold. Its standard deviation at the two centre
pixel planes using all six planes for tracking in a 6\,GeV
electron/positron-beam is measured to be
(2.88\,\pm\,0.08)\,\upmu\meter.Iterative track fits using the formalism of
General Broken Lines are performed to estimate the intrinsic resolution of the
individual pixel planes. The mean intrinsic resolution over the six sensors
used is found to be (3.24\,\pm\,0.09)\,\upmu\meter.With a 5\,GeV
electron/positron beam, the track resolution halfway between the two inner
pixel planes using an equidistant plane spacing of 20\,mm is estimated to
(1.83\,\pm\,0.03)\,\upmu\meter assuming the measured intrinsic resolution.
Towards lower beam energies the track resolution deteriorates due to increasing
multiple scattering. Threshold studies show an optimal working point of the
MIMOSA26 sensors at a sensor threshold of between five and six times their RMS
noise. Measurements at different plane spacings are used to calibrate the
amount of multiple scattering in the material traversed and allow for
corrections to the predicted angular scattering for electron beams
Impact of a Wastewater Treatment Plant Upgrade on Amphipods and Other Macroinvertebrates: Individual and Community Responses
In the present study, we investigated the efficiency of additional wastewater treatment based on powdered activated carbon and its benefit for the ecosystem of a connected river system in the catchment area of Lake Constance, Southern Germany. We focused on the overall health status of gammarids and the integrity of the macrozoobenthic community. Samples were taken up- and down-stream of a wastewater treatment plant (WWTP), as well as before and after its upgrading. The investigations showed that both sex ratio and fecundity of gammarids, as well as the macrozoobenthic community were affected by the effluent prior to the WWTP upgrade. After the upgrade, gammarids from the downstream site did not differ any longer from those collected upstream of the WWTP with respect to the investigated health parameters. Furthermore, the overall number of taxa and, particularly, the number of sensitive taxa within the macrozoobenthic community downstream of the WWTP increased considerably. Therefore, we conclude that the additional treatment with powdered activated carbon was highly efficient to improve invertebrate health and community integrity
SchussenAktivplus: reduction of micropollutants and of potentially pathogenic bacteria for further water quality improvement of the river Schussen, a tributary of Lake Constance, Germany
The project focuses on the efficiency of combined technologies to reduce the release of micropollutants and bacteria into surface waters via sewage treatment plants of different size and via stormwater overflow basins of different types. As a model river in a highly populated catchment area, the river Schussen and, as a control, the river Argen, two tributaries of Lake Constance, Southern Germany, are under investigation in this project. The efficiency of the different cleaning technologies is monitored by a wide range of exposure and effect analyses including chemical and microbiological techniques as well as effect studies ranging from molecules to communities
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