1,014 research outputs found
Particle-level pileup subtraction for jets and jet shapes
We present an extension to the jet area-based pileup subtraction for both jet
kinematics and jet shapes. A particle-level approach is explored whereby the
jet constituents are corrected or removed using an extension of the methods
currently being employed by the LHC experiments. Several jet shapes and nominal
jet radii are used to assess the performance in simulated events with pileup
levels equivalent to approximately 30 and 100 interactions per bunch crossing,
which are characteristic of both the LHC Run I and Run II conditions. An
improved performance in removing the pileup contributions is found when using
the new subtraction method. The performance of the new procedure is also
compared to other existing methods
Erarbeitung von Schwellenwerten zur gezielten Bekämpfung von Zwergsteinbrand (Tilletia controversa) und Steinbrand (Tilletia caries) sowie deren praktische Umsetzung im Öko- Landbau
Dwarf bunt of wheat (Tilletia controversa) and common bunt of wheat (Tilletia caries)
are the most important pathogens in organic cereal production. The aim of this
research work is to find out whether a threshold value for seed is sufficient or whether
the infection potential in the soil must be considered additionally.
For dwarf bunt of wheat two-years-lasting field trials are performed at 3 sites with
susceptible and low-susceptible wheat and spelt cultivars, 4 infection levels and 4
replications. The field trials are designed in a randomized split-block design with
additional marginal-plots, so (1) sowing and harvest will be possible without greater
interaction between the field plots, (2) spore contamination of the soil during harvest
will be assured and (3) the determination of spore inoculum density in the soil after
harvest will be enabled. Only fields with natural spore contamination are chosen. The
field trials for common bunt of wheat are carried out in a similar design with 4
replicates at 4 sites with susceptible and low-susceptible wheat cultivars and two
different sowing times.
For an infestation with dwarf bunt of wheat, diffuse light is sufficient. The wheat
cultivar Capo showed a significantly lower infestation than the cultivar Saturnus. The
infestation of the spelt cultivar Franckenkorn was significantly lower than that of the
cultivar Oberkulmer Rotkorn, with the infestation of spelt cultivars being in principle
lower because of morphological features. The greatest significant number of infested
spikes per m² was found in the variant soil infection. With the dwarf bunt of wheat
results from the first year no threshold values can be determined neither for seed nor
for soil.
In the case of infestation with common bunt of wheat, there were no significant
differences between the early and late sowing dates, nor between the cultivars Capo
and Tommi. The highest bunt spore potential in the soil was found at the field trial site
in Saxony; however, the highest number of infested spikes per m² was not found
there
Workload balancing in distributed virtual reality environments
Virtual Reality (VR) has grown to become state-of-theart
technology in many business- and consumer oriented
E-Commerce applications. One of the major design
challenges of VR environments is the placement of the
rendering process. The rendering process converts the
abstract description of a scene as contained in an object
database to an image. This process is usually done at the
client side like in VRML [1] a technology that requires the
client’s computational power for smooth rendering.
The vision of VR is also strongly connected to the
issue of Quality of Service (QoS) as the perceived realism
is subject to an interactive frame rate ranging from 10 to
30 frames-per-second (fps), real-time feedback
mechanisms and realistic image quality. These
requirements overwhelm traditional home computers or
even high sophisticated graphical workstations over their
limits. Our work therefore introduces an approach for a
distributed rendering architecture that gracefully
balances the workload between the client and a clusterbased
server. We believe that a distributed rendering
approach as described in this paper has three major
benefits: It reduces the clients workload, it decreases the
network traffic and it allows to re-use already rendered
scenes
Schwellenwerte und weitere Entscheidungshilfen bei Befall mit Zwergsteinbrand (Tilletia controversa) und Steinbrand (Tilletia caries)
Beim Zwergsteinbrand zeigte sich, dass bei günstigen Infektionsbedingungen bereits ca. 50 Sporen in 10 g Boden zu einem starken Befall am Erntegut führen. Bei den verwendeten Sorten konnten keine nennenswerten Unterschiede im Befall festgestellt werden. Ein Schwellenwert von 20 Sporen/Korn ist nach den derzeitigen Ergebnissen auch für Zwergsteinbrand ausreichend. Da ein Abschätzen der Winterwitterung schwer möglich ist, wäre ein Grenzwert für das Infektionspotenzial im Boden, vor der Weizen- oder Dinkelsaat, durchaus überlegenswert. Dieser lässt sich aber nach einem einjährigem hohen Befall noch nicht festlegen.
Der Steinbrandbefall ist stark von den Auflaufbedingungen abhängig. Nach zwei vorliegenden Versuchsjahren hat sich gezeigt, dass neben einer gezielten Sortenwahl und einen späten Saattermin (Ende Oktober) der Befall am Erntegut gering gehalten werden kann. Es konnte auch nachgewiesen werden, dass die Infektion vom Boden erfolgt. Zur Aussaat sollte nur Z-Saatgut verwendet werden, denn je höher das ausgesäte Saatgut bereits mit Brandsporen befallen ist, umso höher ist der Befall im nächsten Jahr beim Erntegut. Ziel des Weizenanbaus muss sein, das Sporenpotenzial im Boden und am Erntegut so gering wie möglich zu halten. Für einen Grenzwert im Boden besteht derzeit keine Notwendigkeit, da einem Befall mit entsprechender Sortenwahl und späten Saattermin entgegengewirkt werden kann
Produktivität verschiedener Sojasorten im ostösterreichischen Anbaugebiet
In Austria organic soybeans are mainly produced in the eastern part of the country
due to its temperature requirements. To examine genotypic differences with respect to
seed quality a three-year field trial with seven soybean cultivars was conducted. The
cultivar `Essor´ showed significantly higher (p<0,05) values for corn yield, thousand
grain weight and seed protein content in all three years compared to to the early
maturing cultivar `Merlin´. During the whole observation period the cultivars
`Essor´and `Lambton´ produced most stable corn yields while ´Essor´ and ´Cardiff´
revealed most stable seed protein contents. Based on our results, soybean cultivars of
maturity group 00 had higher grain yields as well as higher seed protein content in
comparison to early maturing cultivars (maturity group 000) grown under natural
conditions prevalent in eastern Austria
Sobre la ocurrencia del cretáceo superior marino en Coihaique , Provincia de Aisén
Using
the CCSD(T) model, we evaluated the intermolecular potential
energy surfaces of the He–, Ne–, and Ar–phosgene
complexes. We considered a representative number of intermolecular
geometries for which we calculated the corresponding interaction energies
with the augmented (He complex) and double augmented (Ne and Ar complexes)
correlation-consistent polarized valence triple-ζ basis sets
extended with a set of 3s3p2d1f1g midbond functions. These basis sets
were selected after systematic basis set studies carried out at geometries
close to those of the surface minima. The He–, Ne–,
and Ar–phosgene surfaces were found to have absolute minima
of −72.1, −140.4, and −326.6 cm<sup>–1</sup> at distances between the rare-gas atom and the phosgene center of
mass of 3.184, 3.254, and 3.516 Å, respectively. The potentials
were further used in the evaluation of rovibrational states and the
rotational constants of the complexes, providing valuable results
for future experimental investigations. Comparing our results to those
previously available for other phosgene complexes, we suggest that
the results for Cl<sub>2</sub>–phosgene should be revised
Evaluation of a field-test kit for triazine herbicides (SensioScreen® TR500) as a fast assay to detect pesticide contamination in water samples
11 pages, 3 figures, 7 tables.-- Available online Nov 16, 2002.A field-test kit (SensioScreen® TR500) for the determination of triazine herbicides in water samples has been evaluated. The test is based on an ELISA method performed on a membrane that allows the visual estimation of the presence of triazine herbicides in <10 min. The kit contains all necessary reagents and equipment, and operates on a very simple protocol. The detection level of this semiquantitative kit has been set at 0.5 μg/l (for the sum of all triazines), although concentration levels of 0.1 μg/l for atrazine can be detected. This is the first time that a commercial field-test kit to control water contamination by herbicides performs in compliance with the EU and USA legislations regarding the limit of detection reached. Evaluation and validation studies have been performed using spiked, certified (AquaCheck) and real environmental samples comparing the results with chromatographic methods. In spite of the semiquantitative–qualitative character of the kit, the results demonstrate that the test SensioScreen® TR500 provides a very good estimation of the atrazine concentration in the sample. This test format could be adapted to the detection of other contaminants of environmental relevance.This work has been supported by CICYT (BIO2000-0351-P4-05) and by INIA (VIN0053-C3).Peer reviewe
Computational and experimental investigation of intermolecular states and forces in the benzene–helium van der Waals complex
A study of the intermolecular potential-energy surface (IPS) and the intermolecular states of the perprotonated and perdeuterated benzene–He complex is reported. From a fit to ab initio data computed within the coupled cluster singles and doubles including connected triples model for 280 interaction geometries, an analytic IPS including two- to four-body atom–atom terms is obtained. This IPS, and two other Lennard-Jones atom–atom surfaces from the literature, are each employed in dynamically exact (within the rigid-monomer approximation) calculations of J = 0 intermolecular states of the isotopomers. Rotational constants and Raman-scattering coefficients for intermolecular vibrational transitions are also calculated for each of the three surfaces. The calculated results are compared with experimental results reported herein pertaining to intermolecular Raman spectra of benzene–He. The calculated rotational constants are compared with experimental values from the literature. The fitted IPS of this work leads to calculated observables that match the experimental results very well. The IPSs from the literature are not as successful, specifically in regard to the intermolecular Raman [email protected]
Study of the benzene⋅N2 intermolecular potential-energy surface
The intermolecular potential-energy surface pertaining to the interaction between benzene and N2 is investigated theoretically and experimentally. Accurate intermolecular interaction energies are evaluated for the benzene–N2 van der Waals complex using the coupled cluster singles and doubles including connected triples [CCSD(T)] method and the aug-cc-pVDZ basis set extended with a set of 3s3p2d1f1g midbond functions. After fitting the energies to an analytic function, the intermolecular Schrödinger equation is solved to yield energies, rotational constants, and Raman-scattering coefficients for the lowest intermolecular levels of several benzene–N2 isotopomers. Experimentally, intermolecular Raman spectra of jet-cooled h6- and d6-benzene–N2 measured at 0.03 cm−1 resolution by mass-selective, ionization-detected stimulated Raman spectroscopies are reported. Seven intermolecular bands are assigned for each isotopomer, including transitions involving intermolecular bending and stretching vibrations and internal rotation about the benzene C6 axis. These Raman data, together with measured rotational constants and binding energies obtained by other groups on benzene–N2, agree well with the theoretical results. Such agreement points to the promise of the quantum chemical methodology employed herein in future investigations of larger van der Waals [email protected]
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