2,213 research outputs found
Two loop mass effects in the static position space QCD-potential
The perturbatively calculable short distance QCD potential is known to two
loops including the effect of massive quarks. Recently, a simple approximate
solution in momentum space was utilized to obtain the potential in coordinate
space. The latter is important in several respects. A comparison with
non-perturbative lattice results is feasible in the overlap regime using light
masses. This might be even more promising employing the concept of
the force between the heavy color singlet sources, which can be easily derived
from the potential. In addition, the better than two percent accuracy bottom
mass determination from -mesons is sensitive to massive charm loops
at the two loop order. We summarize recent results using exact one loop
functions and explicit decoupling parametrizations.Comment: Version to appear in Proceedings of QCD0
К ПРОБЛЕМЕ НАУЧНОЙ ОРГАНИЗАЦИИ ТРУДА ПЕДАГОГА
У статті розглянуті питання наукової організації праці педагога, особливості НОП в освітній
діяльності, проблеми компетентності вчителі в умовах сучасної школи.The article deals with scientific organization of work of the teacher, especially under examination
in educational activities, problems of competence of teachers in modern schools
Wavelet Radiosity
Radiosity methods have been shown to be an effective means to solve the global illumination problem in Lambertian diffuse environments. These methods approximate the radiosity integral equation by projecting the unknown radiosity function into a set of basis functions with limited support resulting in a set of n linear equations where n is the number of discrete elements in the scene. Classical radiosity methods required the evaluation of n2 interaction coefficients. Efforts to reduce the number of required coefficients without compromising error bounds have focused on raising the order of the basis functions, meshing, accounting for discontinuities, and on developing hierarchical approaches, which have been shown to reduce the required interactions to O(n). In this paper we show that the hierarchical radiosity formulation is an instance of a more general set of methods based on wavelet theory. This general framework offers a unified view of both higher order element approaches to radiosity and the hierarchical radiosity methods. After a discussion of the relevant theory, we discuss a new set of linear time hierarchical algorithms based on wavelets such as the multiwavelet family and a flatlet basis which we introduce. Initial results of experimentation with these basis sets are demonstrated and discussed.Engineering and Applied Science
Möglichkeiten und Maßnahmen zur Wahrung und Steigerung der Wettbewerbsfähigkeit der Baden-Württembergischen Wertpapierbörse zu Stuttgart
Die Börsenstrukturen befinden sich international in einer Phase dynamischer Veränderungen.
Der härter gewordene Wettbewerb hinterläßt bei den großen nationalen Börsen tiefe Spuren und führt zu Anpassungsmaßnahmen, die vor allem in der technischen Neuorganisation des Börsenhandels und in der Erweiterung der Produktpalette ihren Ausdruck finden. Regionalbörsen
wie die Baden-Württembergische Wertpapierbörse zu Stuttgart sind dabei einem noch stärkeren Wettbewerbsdruck ausgesetzt, da neben die internationale Konkurrenz noch die
Konkurrenz der deutschen Börsen untereinander tritt.
Das vorliegende Gutachten, das vom Staatsministerium Baden-Württemberg in Auftrag gegeben wurde, widmet sich speziell der Erarbeitung von Vorschlägen, die der Wahrung und Steigerung
der Wettbewerbsfähigkeit der Stuttgarter Wertpapierbörse dienen
The gene space of European mistletoe (Viscum album)
European mistletoe (Viscum album) is a hemiparasitic flowering plant that is known for its very special life cycle and extraordinary biochemical properties. Particularly, V. album has an unusual mode of cellular respiration that takes place in the absence of mitochondrial complex I. However, insights into the molecular biology of V. album so far are very limited. Since the genome of V. album is extremely large (estimated 600 times larger than the genome of the model plant Arabidopsis thaliana) it has not been sequenced up to now. We here report sequencing of the V. album gene space (defined as the space including and surrounding genic regions, encompassing coding as well as 5′ and 3′ non-coding regions). mRNA fractions were isolated from different V. album organs harvested in summer or winter and were analyzed via single-molecule real-time sequencing. We determined sequences of 39 092 distinct open reading frames encoding 32 064 V. album proteins (designated V. album protein space). Our data give new insights into the metabolism and molecular biology of V. album, including the biosynthesis of lectins and viscotoxins. The benefits of the V. album gene space information are demonstrated by re-evaluating mass spectrometry-based data of the V. album mitochondrial proteome, which previously had been evaluated using the A. thaliana genome sequence. Our re-examination allowed the additional identification of nearly 200 mitochondrial proteins, including four proteins related to complex I, which all have a secondary function not related to respiratory electron transport. The V. album gene space sequences are available at the NCBI
Исследование алгоритмов функционирования СМО с использованием библиотеки SimEvents
Выпускная квалификационная работа 80 с., 18 рис., 6 табл., 21 источник.
Объект исследования — модель управления графитовыми стержнями в ядерном реакторе.
Цель работы — разработка модели управления замедляющими стержнями в реакторе с использованием библиотеки SimEvents.
Изучены принципы имитационного моделирования с помощью библиотек SimEvents, Simulink.
Разработана модель управления графитовыми стержнями в реакторе, получены параметры системы, проведен их анализ.
Модель может использоваться как имитатор физического процесса в атомном производстве.
Имитационная модель дает подтверждение расчетов, прогноз работы системы, позволяет исследовать работу в критических режимах.
Планируется изучение новых характеристик системы, разработка более сложной модели, параметров, влияющих на новую модельGraduation qualification project consist of 80 p., 18 fig., 6 tab., 21 sources.
The object of this study is graphite rods’s control model in nuclear reactors.
The purpose of work – graphite rods’s control model development using SimEvents in nuclear reactors.
Is studied the simulation principles using libraries SimEvents, Simulink.
Are obtained the model of the control rods in the reactor graphite, the system parameters , their analysis was carried out.
The model can be used as a simulator of a physical process in nuclear industry.
A simulation model provides evidence calculations, the forecast of the system, allows you to explore the critical operation.
It is planned to study the characteristics of the new system, the development of a more complex model, the parameters affecting a mode
The Influence of Land Use Intensity on the Plant-Associated Microbiome of Dactylis glomerata L.
In this study, we investigated the impact of different land use intensities
(LUI) on the root-associated microbiome of Dactylis glomerata (orchardgrass).
For this purpose, eight sampling sites with different land use intensity
levels but comparable soil properties were selected in the southwest of
Germany. Experimental plots covered land use levels from natural grassland up
to intensively managed meadows. We used 16S rRNA gene based barcoding to
assess the plant-associated community structure in the endosphere, rhizosphere
and bulk soil of D. glomerata. Samples were taken at the reproductive stage of
the plant in early summer. Our data indicated that roots harbor a distinct
bacterial community, which clearly differed from the microbiome of the
rhizosphere and bulk soil. Our results revealed Pseudomonadaceae,
Enterobacteriaceae and Comamonadaceae as the most abundant endophytes
independently of land use intensity. Rhizosphere and bulk soil were dominated
also by Proteobacteria, but the most abundant families differed from those
obtained from root samples. In the soil, the effect of land use intensity was
more pronounced compared to root endophytes leading to a clearly distinct
pattern of bacterial communities under different LUI from rhizosphere and bulk
soil vs. endophytes. Overall, a change of community structure on the
plant–soil interface was observed, as the number of shared OTUs between all
three compartments investigated increased with decreasing land use intensity.
Thus, our findings suggest a stronger interaction of the plant with its
surrounding soil under low land use intensity. Furthermore, the amount and
quality of available nitrogen was identified as a major driver for shifts in
the microbiome structure in all compartments
Quark confinement and the bosonic string
Using a new type of simulation algorithm for the standard SU(3) lattice gauge
theory that yields results with unprecedented precision, we confirm the
presence of a correction to the static quark potential at large
distances , with a coefficient as predicted by the bosonic string
theory. In both three and four dimensions, the transition from perturbative to
string behaviour is evident from the data and takes place at surprisingly small
distances.Comment: TeX source, 21 pages, figures include
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