Modelling of transient interference phenomena in collinear laser spectroscopy

Collinear laser spectroscopy of fast atomic beams has been established as one of the main tools to perform precision experiments with atoms containing short-lived nuclei. Although highly sensitive, the spectral resolution of these techniques is typically limited to several MHz. Here, we study the use of transient interference phenomena to potentially improve the experimental resolution. Previous attempts to implement Ramsey-type measurements with fast beams were limited by the lack of understanding of the observed line shapes. By using a simple model, we provide a satisfactory description of the previously observed line shapes, and propose alternative experimental schemes to improve the resolution in fast ion-beam experiments.Comment: 7 pages without references, 8 figure

Beam test evaluation of electromagnetic calorimeter modules made from proton-damaged PbWO4 crystals

The performance of electromagnetic calorimeter modules made of proton-irradiated PbWO4 crystals has been studied in beam tests. The modules, similar to those used in the Endcaps of the CMS electromagnetic calorimeter (ECAL), were formed from 5x5 matrices of PbWO4 crystals, which had previously been exposed to 24 GeV protons up to integrated fluences between 2.1 x 10(13) and 1.3 x 10(14) cm(-2). These correspond to the predicted charged-hadron fluences in the ECAL Endcaps at pseudorapidity eta = 2.6 after about 500 fb(-1) and 3000 fb(-1) respectively, corresponding to the end of the LHC and High Luminosity LHC operation periods. The irradiated crystals have a lower light transmission for wavelengths corresponding to the scintillation light, and a correspondingly reduced light output. A comparison with four crystals irradiated in situ in CMS showed no significant rate dependence of hadron-induced damage. A degradation of the energy resolution and a non-linear response to electron showers are observed in damaged crystals. Direct measurements of the light output from the crystals show the amplitude decreasing and pulse becoming faster as the fluence increases. The latter is interpreted, through comparison with simulation, as a side-effect of the degradation in light transmission. The experimental results obtained can be used to estimate the long term performance of the CMS ECAL

Fair Trade aus der Sicht der südosteuropäischen Peripherie : Fallstudie Serbien

Unter den Auswirkungen der Globalisierung ist die Welt zu einem globalen Dorf geworden, aber die Unterschiede zwischen den Regionen sind immer noch groß und oft leidet unser Planet darunter. Der Faire Handel (englisch: FAIR TRADE) wurde aufgebaut, um diese Kluft zu überwinden. Der Ausdruck „Fairtrade" in der zusammengeschriebenen Form bezeichnet das Fairtrade-System und somit die Vergabe des Fairtrade-Siegels. Mit dem Fairtrade-Siegel sind die Produkte gekennzeichnet, die nach den Standards von Fairtrade Labelling Organizations International (kurz: Fairtrade International, FLO) gehandelt werden. Alle hier aufgeführten Siegel aus Fairem Handel ermöglichen den Kleinbauern- und Kleinbäuerinnenkooperativen stabilere Preise sowie langfristige Handelsbeziehungen und eine nachhaltige Entwicklung.Die Hauptregel vom Fairtrade-System ist, dass alle Entwicklungsländer, als die Länder in denen Fairtrade-Produkte in der Primärproduktion hergestellt, gehandelt und konsumiert werden können, willkommen sind. Die Entwicklungsländer der südosteuropäischen Peripherie dürfen den Fairtrade-Handel und den Fairtrade-Konsum praktizieren, aber eine Fairtrade-Primärproduktion für ihre kleinen ProduzentInnen ist unmöglich. Der Grund dafür ist, dass sie aus dem reichen „globalen Norden“ kommen und „ausreichend“ entwickelt sind. Das ist gleichzeitig ein Nachteil für das globale Fairtrade System.Ziel dieser Arbeit ist es, die Gliederung des „globalen Nordens“ und des „globalen Südens“ im Fairtrade-System aufzulösen, indem die Potenziale beider Seiten aufgezeigt werden um das „Global Nord - Global Süd“ Paradigma zu wechseln. Welche Potenziale und Bedürfnisse die Republik Serbien für den vollständigen Zugang zum Fairtrade-System hat, und was „fair“ für die kleinen Bauern und Bäuerinnen im Land bedeutet, wird in der vorliegenden Arbeit diskutiert.Under the effects of globalization, the world became a global village, however, the differences between regions are still vast and often our planet suffers from it. The Fair Trade movement (deutsch: Faire Handel) was established to decrease this gap. The expression “Fairtrade”, written together, means the Fairtrade system that launched the “Fairtrade Mark”. All products produced and traded in relation to the standard of the Fairtrade International are marked (coded) by the Fairtrade Mark. Moreover, each logo from the Fair Trade movement enables stable prices as well as long-term trade relations to the cooperatives of small-scale producers and sustainable development.The main idea of the Fairtrade-system is that all developing countries are welcome to implement the Fairtrade concept in primary production, trade and consumption of goods and natural resources. The developing countries of the Southeast European periphery are allowed to practice Fairtrade trading and consumption, however, small-scale producers are not permitted to produce under Fairtrade terms in primary production. The reason behind this, is the belief that they belong to the wealthy, developed “Global North”, and that they are therefore "sufficiently" developed. This is, at the same time, the disadvantage for the global Fairtrade-system itself.The aim of this work is to bridge the structure of the "Global North" and the "Global South" in the Fairtrade system, by showing potentials on both sides in order to change the "Global North - Global South" paradigm. The potentials and needs that the Republic of Serbia has for the full access to a Fairtrade-system, as well as the importance of “fair” to the small-scale producers in the country, are discussed in this paper.Jovan Jovanović, Dipl. ÖkonomZusammenfassungen in Deutsch und EnglischAbweichender Titel laut Übersetzung des Verfassers/der VerfasserinKarl-Franzens-Universität Graz, Masterarbeit, 2019(VLID)443771

On the evolution of laminar to turbulent transition and breakdown to turbulence

Starting from the basic conservation laws of fluid flow, we investigated transition and breakdown to turbulence of a laminar flat plate boundary layer exposed to small, statistically stationary, two-component, three-dimensional disturbances. The derived equations for the statistical properties of the disturbances are closed using the two-point correlation technique and invariant theory. By considering the equilibrium solutions of the modeled equations, the transition criterion is formulated in terms of a Reynolds number based on the intensity and the length scale of the disturbances. The deduced transition criterion determines conditions that guarantee maintenance of the local equilibrium between the production and the viscous dissipation of the disturbances and therefore the laminar flow regime in the flat plate boundary layer. The experimental and numerical databases for fully developed turbulent channel and pipe flows at different Reynolds numbers were utilized to demonstrate the validity of the derived transition criterion for the estimation of the onset of turbulence in wall-bounded flows

ANAMNESTIC AND POPULATION CHARACTERISTICS OF THE BREECH DELIVERIES IN SUMADIJA REGION

Breech presentation implies vertical position of the fetus, accounting for 3-4% of all monofetal deliveries. Perinatal morbidity and mortality are significantly higher in breech deliveries than in head presentation deliveries.The aim of the investigation was to examine the association between the anamnestic and population characteristics of the breech deliveries and the same characteristics in the head deliveries.Study group included 282 mothers who had breech deliveries and 282 mothers in control group who had head presentation deliveries. All the babies were delivered at the Clinic of Obstetrics and Gyneclogy Kragujevac.The population sample - the subject of the study encompassed mothers from Sumadija region with the center in Kragujevac as the capital and biggest city in the region.Distribution of probabilities according to profession or education of mothers was similar in both groups. The mean age of the mothers in both groups was 26.8 years. Significantly, the largest number of mothers from both groups was between 20 and 29 years of age, e.g. 70 %.With significantly high probability, the pregnancy progression in both groups was positive (85%), without maintaining pregnancy. The presence of associated disease was significantly higher, especially hypertension and diabetes in mothers who had breech deliveries compared to mothers who had head presentation deliveries

Quality assurance of the Serbian national E-PRTR register reported data for large combustion plants

U periodu od 2007. do 2009. godine, a radi kontrole i ograničenja emisije iz industrije u skladu sa Pravilnikom o metodologiji za izradu integralnog katastra zagađivača, za potrebe Integralnog katastra zagađivača niz postrojenja su bila dužna da dostave podatke o količinama zagađujućih materija ispuštenih u vazduh i vode, kao i o generisanju otpada. Ovaj registar je sastavni deo informacionog sistema zaštite životne sredine Republike Srbije, koji vodi i čiju kontrolu podataka vrši Agencija za zaštitu životne sredine. Cilj ovog rada je kvalitativna analiza podataka o emisiji zagađujućih materija u vazduh (SOx, NOx i praškaste materije), na osnovu dostavljenih podataka za 2009. godinu. Proračun emisija je izvršen na osnovu metodologije koja je propisana Konvencijom o prekograničnom zagađenju vazduha na velikim udaljenostima. Radom su obuhvaćena velika ložišta sa izlazom toplote većim od 50 MW. Analiza je obuhvatila 37 postrojenja sa ukupno 61 emiterom.The Serbian E-PRTR register (The European Pollutant Release and Transfer Register) was established in 2007 and harmonized with PRTR protocol of Arhus convention and E-PRTR directive. In this paper, the quality of 2009 data reported to the Serbian PRTR register was analyzed. The analysis includes 37 large combustion plants with the capacity equal or greater than 50 MW. The combustion plants include power plants, heating plants and industrial energy units. The calculation is done using EMEP-EEA 2009 methodology and Tier 2 approach. The analysis obtained presents an overview of the quality of the reported data for SOx, NOx and TSP emissions for 61 combustion units, e.g., emitters (stacks). The results show that all 61 emitters reported data with the deviation greater than 25%, with 55% of the emitters reporting data that differed from pollutant to pollutant in comparison to the estimated data. Out of those, 30% of the emitters reported smaller and 8% reported greater emissions than estimated emissions with 7% of the emitters not submitting any emissions data. The analysis also includes calculation of the emissions scope limit within 95% confidence interval. According to these results, it can be concluded that only 15% of the emitters have emission levels that fall within the scope limits, 47% of the emitters reported data of which two data fall within the scope limits, 28% of the emitters reported data of which only one data fall within the scope limits, 3% of the emitters had data that didn't fall within the scope limits, and 7% did not reported any emission data. The results of the analysis can be summarized as: 1) operators in facilities do not know how to calculate emissions from their sources, and 2) the application of global emission factors can lead to considerable errors. The main reasons for significant deviation are different fuel quality, type of technical units and human error, thus national emission factors should be developed

VOC emission from oil refinery and petrochemical wastewater treatment plant estimation

As a consequence of environmental legislation improvement in Serbia for industrial producers, especially future holders of Integrated Pollution Prevention Control (IPPC) license, it is necessary to report annually on emissions of pollutants emitted into the environment and pay certain environmental fees. Wastewater treatment plants can be significant sources of volatile organic compounds (VOCs) diffuse emissions, which are difficult to measure directly. Reporting obligations may also expand to benzene and other VOCs in the near future. This paper deals with gaseous emissions calculations from an API separator, based on emission factors and adequate software applications. The analyses results show that the estimated emission values are significantly different, depending on the applied method. VOC emissions have been estimated using US EPA and CONCAWE emissions factors. Calculated emissions range from 40 to 4500 tons/year for oil refinery WWTP of 2,000,000 m3/year. The calculations of benzene and toluene emissions have been performed using three methods: U.S. EPA emission factors, and WATER9 and Toxchem+ software. The calculated benzene and toluene emissions range from 5.5-60 and 0.7-20 tons/year, respectively. U.S. EPA emission factors give the highest values and Toxchem+ the lowest estimation values. Sensitivity analysis of obtained results included the following parameters: flow, temperature, oil content and the concentration of benzene and toluene in the effluent. The wide range of results indicates the need for their official interpretation for the conditions that are typical for Serbia if, in the future, the "polluter pays" principle should be applied to VOC and benzene emissions. The proposal is that adequate national emission factors should be established.Stupanjem na snagu novih zakonskih akata, industrijski zagađivači u Srbiji - budući nosioci integrisane dozvole, dužni su da na godišnjem nivou izveštavaju o emisijama štetnih gasova koji se ispuštaju u životnu sredinu i da u skladu sa time plaćaju određene ekološke naknade. Obaveza izveštavanja u skorijoj budućnosti može se proširiti na benzen i druge lako isparljive ugljovodonike. Predmet analize ovog rada su primena emisionih faktora i softverske simulacije za proračun gasovitih emisija iz postrojenja za tretman otpadnih voda. Rezultati pokazuju da se izračunate vrednosti emisija značajno razlikuju od metode do metode, a u diskusiji se posebna pažnja obraća na procenu pouzdanosti svake od njih