164 research outputs found

    PuLSE-I: Deriving instances from a product line infrastructure

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    Reusing assets during application engineering promises to improve the efficiency of systems development. However, in order to benefit from reusable assets, application engineering processes must incorporate when and how to use the reusable assets during single system development. However, when and how to use a reusable asset depends on what types of reusable assets have been created.Product line engineering approaches produce a reusable infrastructure for a set of products. In this paper, we present the application engineering process associated with the PuLSE product line software engineering method - PuLSE-I. PuLSE-I details how single systems can be built efficiently from the reusable product line infrastructure built during the other PuLSE activities

    A study of the United States coal resources

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    Geologically significant coal resources were identified. Statistically controlled tonnage estimates for each resource type were prepared. Particular emphasis was placed on the identification and description of coals in terms of seam thickness, inclination, depth of cover, discontinuities caused by faulting and igneous intrusion, and occurrence as isolated or multiseam deposits. The national resource was organized into six major coal provinces: the Appalachian Plateau, the Interior Basins, the Gulf Coastal Plain, the Rocky Mountain Basins, the High Plains, and North Alaska. Each basin within a province was blocked into subareas of homogeneous coal thickness. Total coal tonnage for a subarea was estimated from an analysis of the cumulative coal thickness derived from borehole or surface section records and subsequently categorized in terms of seam thickness, dip, overburden, multiseam proportions, coal quality, and tonnage impacted by severe faulting and igneous intrusions. Confidence intervals were calculated for both subarea and basin tonnage estimates

    Nahinfrarote und zirkular polarisierte Lumineszenz von Donor-Kupfer(I)-Akzeptorkomplexen

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    Das Design molekularer Emitter, die effiziente nahinfrarote (NIR) und zirkular polarisierte Lumineszenz (CPL) ermöglichen, sind zwei Herausforderungen der aktuellen Forschung, welche im Rahmen dieser Arbeit durch verschiedene AnsĂ€tze untersucht wurden. Als Strukturmotiv wurden Donor-Kupfer(I)-Akzeptorkomplexe gewĂ€hlt, welche sich innerhalb der vergangenen fĂŒnf Jahre zu vielversprechenden Alternativen zu den bis dato fĂŒhrenden Iridium(III)-emittern entwickelt haben. Die vorwiegend linearen Kupfer(I)-komplexe mit Amidodonoren und Carbenakzeptoren weisen hĂ€ufig nicht den fĂŒr Übergangsmetallkomplexe ĂŒblichen Emissionsprozess der Phosphoreszenz auf, sondern thermisch aktivierte verzögerte Fluoreszenz (TADF). Hierdurch lassen sich hohe strahlende Ratenkonstanten kr > 106 s 1 realisieren, welche die der phosphoreszierenden Iridium(III)-emitter bereits ĂŒbertreffen. Allerdings ist der Emissionsbereich, in welchem die bislang bekannten Kupfer(I)-emitter kompetitiv mit Komplexen schwererer Metalle sind, auf den blauen bis orangen Farbbereich beschrĂ€nkt. Ferner wurde diese vielversprechende Kupfer(I)-komplexklasse bisher nicht auf die AusprĂ€gung ihrer CPL, gemessen am Emissionsdissymmetriefaktor glum, hin untersucht. Im Rahmen dieser Arbeit wurde zum einen durch das EinfĂŒhren unterschiedlicher Komplexgeometrien bzw. chiraler Strukturmotive die Emission der Kupfer(I)-emitter bathochrom verschoben und CPL ermöglicht. So weisen die synthetisierten Halbsandwich- bzw. trigonalen Komplexe Phosphoreszenz im orangen bzw. NIR-Spektralbereich auf. Wohingegen mit dem [2.2]Paracyclophanyl- und dem Binaphtylmotiv zwei fĂŒr Kupfer(I)-basierte TADF-Emitter vielversprechende Strukturmotive identifiziert wurden, die glum ≀ 7∙10 3 ermöglichen. Zum anderen wurden Anwendungsmöglichkeiten der hergestellten Kupfer(I)-komplexe wie die Verwendung als Einzelphotonenquellen und als Emittermaterial in OLEDs aufgezeigt.Phase transitions in biological systems are controversially discussed. As the origin of nonlinearities, they have been suggested responsible for cellular functions including nerve pulse propagation. In pure lipid interfaces characteristic functions, such as permeability, are modulated during a transition. These relations could have drastic implications for cells because their membranes are lipid-based. However, evidence for these transitions in cellular membranes of excitable cells - which are involved in the transmission of nerve pulses - has not been provided so far. Within this thesis thermodynamic phase states in lipid-based interfaces are characterized based on the use of a fluorescent dye (Atto488-DPPE) as local state reporter. Optical state diagrams of artificial, lipid interfaces are recorded, and state dependent kinetics investigated. Upon the straightforward application of this method to single, neuronal cells, a nonlinearity in the optical response is detected within the cellular membrane and identified as phase transition. The transition is extraordinary sharp (1°C) and sensitive to pH variations in the extracellular buffer. The existence of distinct physical phase states in cellular membranes and their highly nonlinear characteristic provides strong evidence that the membrane state is indeed crucial for excitability and conduction of nerve pulses. The results further underline that the membrane state has the potential to modify cell functionality in general as it is subject to modulation by physiologically important parameters such as pH

    Zustandsselektive Untersuchung der Elektroneneinfangprozesse in hochgeladene Uranionen durch Nachweis der charakteristischen Projektilstrahlung

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    Die intensiven gekĂŒhlten Schwerionenstrahlen des ESR-Speicherrings in Kombination mit dem dort installierten Überschallgastarget bieten einzigartige Möglichkeiten, Elektroneneinfangprozesse bei unterschiedlichen Projektilenergien zu untersuchen. In der vorliegenden Arbeit wurde die Emission der charakteristischen Balmerstrahlung detailliert nach (n, j)-ZustĂ€nden untersucht; die Lyman-alpha-Strahlung konnte aufgrund der großen Feinstrukturaufspaltung des 2p3/2-Niveaus darĂŒber hinaus auch nach der Besetzung der magnetischen UnterzustĂ€nde untersucht werden. Hierbei wurde gezeigt, dass der Einfangmechanismus einen starken Einfluss auf die Besetzung der magnetischen UnterzustĂ€nde und damit auf die WinkelabhĂ€ngigkeit der Emission der charakteristischen Photonen hat. Erstmals konnte an einem schweren Stoßsystem die Multipolmischung beim Ly-alpha1-Übergang mit großer Genauigkeit nachgewiesen werden; es ergab sich eine sehr gute Übereinstimmung mit der theoretischen Vorhersage. Aus dem Vergleich der Messung der Anisotropie bei höheren Energien mit der Vorhersage einer relativistisch exakten Theorie wurde geschlossen, dass die Messwerte nur dann erklĂ€rt werden können, wenn die Mischung von E1- und M2-ÜbergĂ€ngen berĂŒcksichtigt wird. Durch den Vergleich der als zuverlĂ€ssig anzusehenden Vorhersage fĂŒr den REC-Prozeß mit den Messwerten konnte, erstmals fĂŒr atomare ÜbergĂ€nge in Schwerionen, die Beeinflussung der messbaren Anisotropie durch Mischung der Strahlung unterschiedlicher MultipolaritĂ€ten aufgedeckt werden. Hiermit war es möglich, das ÜbergangsratenverhĂ€ltnis Gamma M2 / Gamma E1 und daraus das ÜbergangsamplitudenverhĂ€ltnis / zu extrahieren. Dieser kleine Beitrag(<1%) ist mit anderen Methoden nicht zu vermessen. Die beiden nichtrelativistischen Theorien, den nichtradiativen Einfang in das Projektil beschreiben, liefern bei den totalen Einfangswirkungsquerschnitten nahezu gleiche Ergebnisse in Übereinstimmung mit dem Experiment. Auch die (n, j)-differentiellen Querschnitte zeigen bei dem Vergleich mit den gemessenen Balmerspektren eine sehr gute Übereinstimmung. Erst wenn die magnetischen UnterzustĂ€nde in die Untersuchung miteinbezogen werden, weichen die beiden Theorien voneinander ab. Unter Einbeziehung der Multipolmischung stimmt die Vorhersage der CDW-Theorie mit den Messwerten ĂŒberein; die andere Theorie unterschĂ€tzt das Alignment des 2p3/2-Zustands und die daraus folgende Anisotropie der Lyman-alpha1-Strahlung. Es muss hervorgehoben werden, dass es durch die Anwendung der Abbremstechnik fĂŒr nacktes Uran gelungen ist, diese Prozesse in einem Bereich extrem starker Störung (Q/v) zu untersuchen. Dieser Bereich ist im Allgemeinen experimentell nicht zugĂ€nglich und ist eine Herausforderung fĂŒr die theoretische Beschreibung. Wie sich aus den AusfĂŒhrungen zu den Zerfallskaskaden ergibt, ist die Messung des Alignments bei niedrigen Stoßenergien stark von Kaskadeneffekten beeinflusst. Das bedeutet, dass das Alignment der Lyman-alpha1-Strahlung sowohl durch den direkten Einfang als auch durch die Zerfallskaskade bestimmt ist. Dieses resultiert in einer von der jeweiligen Theorie abhĂ€ngigen Vorhersage, wodurch sich eine integrale Aussage ĂŒber die GĂŒte einer bestimmten Beschreibung ableiten lĂ€sst

    Characterization of fast-growing foams in bottling processes by endoscopic imaging and convolutional neural networks

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    Regardless of whether the occurrence of foams in industrial processes is desirable or not, the knowledge about the characteristics of their formation and morphology is crucial. This study addresses the measuring of characteristics in foam and the trailing bubbly liquid that result from air bubble entrainment by a plunging jet in the environment of industry-like bottling process es of non-carbonated beverages. Typically encountered during the bottling of fruit juices, this process configuration is characterized by very fast filling speeds with high dynamic system parameter changes. Especially in multiphase systems with a sensitive disperse phase like gas bubbles, the task of its measurement turns out to be difficult. The aim of the study is to develop and employ an image processing capability in real geometries under realistic industrial conditions, e.g. as opposed to a narrow measurement chamber. Therefore, a typically sized test bottle was only slightly modified to adapt an endoscopic measurement technique and to acquire image data in a minimally invasive way. Two convolutional neural networks (CNNs) were employed to analyze irregular non-overlapping bubbles and circular overlapping bubbles. CNNs provide a robust object recognition for varying image qualities and therefore can cover a broad range of process conditions at the cost of a time-consuming training process. The obtained single bubble and population measurements allow approximation, correlation and interpretation of the bubble size and shape distributions within the foam and in the bubbly liquid. The classification of the measured foam morphologies and the influence of operating conditions are presented. The applicability to the described test case as an industrial multiphase process reveals high potential for a huge field of operations for particle size and shape measurement by the introduced method

    Towards a method for rigorous development of generic requirements patterns

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    We present work in progress on a method for the engineering, validation and verification of generic requirements using domain engineering and formal methods. The need to develop a generic requirement set for subsequent system instantiation is complicated by the addition of the high levels of verification demanded by safety-critical domains such as avionics. Our chosen application domain is the failure detection and management function for engine control systems: here generic requirements drive a software product line of target systems. A pilot formal specification and design exercise is undertaken on a small (twosensor) system element. This exercise has a number of aims: to support the domain analysis, to gain a view of appropriate design abstractions, for a B novice to gain experience in the B method and tools, and to evaluate the usability and utility of that method.We also present a prototype method for the production and verification of a generic requirement set in our UML-based formal notation, UML-B, and tooling developed in support. The formal verification both of the structural generic requirement set, and of a particular application, is achieved via translation to the formal specification language, B, using our U2B and ProB tools

    α2-adrenoceptor blockade accelerates the neurogenic, neurotrophic, and behavioral effects of chronic antidepressant treatment

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    Slow-onset adaptive changes that arise from sustained antidepressant treatment, such as enhanced adult hippocampal neurogenesis and increased trophic factor expression, play a key role in the behavioral effects of antidepressants. alpha(2)-Adrenoceptors contribute to the modulation of mood and are potential targets for the development of faster acting antidepressants. We investigated the influence of alpha(2)-adrenoceptors on adult hippocampal neurogenesis. Our results indicate that alpha(2)-adrenoceptor agonists, clonidine and guanabenz, decrease adult hippocampal neurogenesis through a selective effect on the proliferation, but not the survival or differentiation, of progenitors. These effects persist in dopamine beta-hydroxylase knock-out (Dbh(-/-)) mice lacking norepinephrine, supporting a role for alpha(2)-heteroceptors on progenitor cells, rather than alpha(2)-autoreceptors on noradrenergic neurons that inhibit norepinephrine release. Adult hippocampal progenitors in vitro express all the alpha(2)-adrenoceptor subtypes, and decreased neurosphere frequency and BrdU incorporation indicate direct effects of alpha(2)-adrenoceptor stimulation on progenitors. Furthermore, coadministration of the alpha(2)-adrenoceptor antagonist yohimbine with the antidepressant imipramine significantly accelerates effects on hippocampal progenitor proliferation, the morphological maturation of newborn neurons, and the increase in expression of brain derived neurotrophic factor and vascular endothelial growth factor implicated in the neurogenic and behavioral effects of antidepressants. Finally, short-duration (7 d) yohimbine and imipramine treatment results in robust behavioral responses in the novelty suppressed feeding test, which normally requires 3 weeks of treatment with classical antidepressants. Our results demonstrate that alpha(2)-adrenoceptors, expressed by progenitor cells, decrease adult hippocampal neurogenesis, while their blockade speeds up antidepressant action, highlighting their importance as targets for faster acting antidepressants

    Electron Loss from 1.4-MeV / u U\u3csup\u3e4,6,10+\u3c/sup\u3e Ions Colliding with Ne, N₂, and Ar Targets

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    Absolute, total, single- and multiple-electron-loss cross sections are measured for 1.4-MeV / u U4,6,10+ ions colliding with neon and argon atoms and nitrogen molecules. It is found that the cross sections all have the same dependence on the number of electrons lost and that multiplying the cross sections by the initial number of electrons in the 6s, 6p, and 5f shells yields good agreement between the different projectiles. By combining the present data with previous measurements made at the same velocity, it is shown that the scaled cross sections slowly decrease in magnitude for incoming charge states between 1 and 10, whereas the cross sections for higher-charge-state ions fall off much more rapidly

    Relativistic quantum dynamics in strong fields: Photon emission from heavy, few-electron ions

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    Recent progress in the study of the photon emission from highly-charged heavy ions is reviewed. These investigations show that high-ZZ ions provide a unique tool for improving the understanding of the electron-electron and electron-photon interaction in the presence of strong fields. Apart from the bound-state transitions, which are accurately described in the framework of Quantum Electrodynamics, much information has been obtained also from the radiative capture of (quasi-) free electrons by high-ZZ ions. Many features in the observed spectra hereby confirm the inherently relativistic behavior of even the simplest compound quantum systems in Nature.Comment: Version 18/11/0

    Effect of Antihypertensive Therapy with Alpha Methyldopa on Levels of Angiogenic Factors in Pregnancies with Hypertensive Disorders

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    Antihypertensive drugs are believed to lower blood pressure in pre-eclampsia by direct or central vasodilatory mechanisms. However, they could also act by decreasing production of anti-angiogenic proteins involved in the pathophysiology of hypertension and proteinuria in pre-eclampsia (PE). The aim of our study was to evaluate the impact of antihypertensive therapy with alpha methyldopa on maternal circulating levels and placental production of soluble fms-like tyrosine kinase 1 (sFlt-1), soluble endoglin (sEng), vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) in hypertensive disorders of pregnancy
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