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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Cosmic ray 2H/1H flux ratio measurement with the AMS-02 experiment / Medição da razão 2H/1H de fluxo em raios cósmicos com o experimento AMS-02

Lordello, Vitor Diorio 26 September 2017 (has links)
The Alpha Magnetic Spectrometer (AMS-02) is a cosmic ray detector operating aboard the International Space Station (ISS) since May 2011. The identification of cosmic ray deuterium and hydrogen particles is the main goal of this work. Using the data collected by the AMS-02 experiment between May 2011 and May 2014 we provide the measurement of the 2H to the 1H ratio between 0.7 and 7 GeV/n. Cosmic rays are mainly composed of hydrogen nuclei. No significant amount of deuterium nuclei is expected to be released from galactic sources since they are destroyed rather than formed in thermonuclear reactions inside stars. As a consequence of their production history, they are part of a class of secondary stable nuclei that provide information on the propagation of cosmic rays in the galaxy. Despite their relevance for propagation studies, very few measurements of deuterium exist above 1 GeV/n, due to the poor isotopic separation capacity of previous experiments. For this reason, the deuterium to hydrogen flux ratio is a very important measurement to be carried out using the data collected by the AMS-02 experiment. The mass and the isotopic composition of cosmic-rays nuclei can be measured by the AMS-02 experiment using measurements of the momentum (provided by the tracker) and velocity of the particles (provided by the Time-of-Flight and the RICH). This analysis is one of the first to be focused on hydrogen isotopic composition with AMS-02 data, and our results are in fair agreement with a similar and independent analysis that has been carried out within the Collaboration. / O Espectômetro Magnético Alpha (AMS-02) é um detetor de raios cósmicos operando na Estação Espacial Internacional (ISS) desde maio de 2011. O principal objetivo deste trabalho é a identificação de deutério e hidrogênio nos raios cósmicos. Usando dados coletados pelo experimento AMS-02 entre maio de 2011 e maio de 2014 foi medida a razão entre os fluxos de 2H e 1H entre 0.7 e 7 GeV/n. Raios cósmicos são compostos, principalmente, por núcleos de hidrogênio. Não é esperado que fontes galácticas de raios cósmicos liberem uma quantidade significativa de núcleos de deutério, já que eles são destruidos, em vez de formados, nas reações termonucleares no interior de estrelas. Assim, eles fazem parte de uma classe de partículas secundárias estáveis que fornecem informações acerca da propagação de raios cósmicos na galáxia. Apesar da relevância para o estudo da propagação de raios cósmicos, poucas medidas da sua quantidade acima de 1 GeV/n existem, devido à baixa capacidade de separação de isótopos de prévios experimentos. Por isso a razão entre os fluxos de deutério e hidrogênio é uma importante medida a ser feita com os dados do AMS-02. A massa, e portanto a composição isotópica dos raios cósmicos, pode ser medida pelo AMS-02 a partir das medições de momento (realizada pelo tracker) e velocidade (realizadas pelo ToF e RICH). Essa análise é uma das primeiras a focar na composição isotópica do hidrogênio com dados do AMS-02, e os resultados estão razoavelmente em acordo com análises independendes semelhantes realizadas na colaboração AMS.
132

Nutzung von Prozessparametern automatischer Melksysteme für die Erkennung von Eutererkrankungen unter Verwendung der Fuzzy Logic

Köhler, Stefan Daniel 22 October 2002 (has links)
Das Ziel der Arbeit bestand darin zu untersuchen, inwieweit durch Kombination von einfach zu erhebenden Daten des Melkprozesses mittels Fuzzy Logic die Bewertung der Eutergesundheit in Automatischen Melksystemen (AMS) verbessert werden kann. Eigene Forschungen richteten sich auf die Evaluierung unterschiedlicher Milch- bzw. Melkparameter hinsichtlich ihrer Eignung als Inputvariable verfeinerter Erkennungsmodelle für Euterkrankheiten am Melkroboter sowie auf die Entwicklung und Optimierung von Fuzzy Logic Modellen. Im Rahmen eines Vorversuches ist geprüft worden, welche Variablen Eingang in das Erkennungsmodell finden sollten. Zu diesem Zweck wurden neben der Erhebung von Prozessdaten eines AMS Astronaut(r) am 26. und 27. Juli 2001 mit Geräten des Typs LactoCorder(r) low flow insgesamt 754 Einzelmessungen an Eutervierteln durchgeführt und verarbeitet. Die Auswertung dieses Datenmaterials ergab, dass zwischen "unauffälligen", d.h. mehr oder weniger gesunden, und "auffälligen", d.h. mehr oder minder kranken Eutervierteln gewisse Unterschiede hinsichtlich der viertelbezogenen Parameter normierte Milchbildungsrate und normierter Milchfluss sowie der normierten Zwischenmelkzeit bestehen, welche für eine Modellierung nutzbar sind. Auch die elektrische Leitfähigkeit sollte in das weitere Vorgehen einbezogen werden. Die Funktionalität einfacher Fuzzy Logic Modelle ist anhand von 74 erstellten Datensätzen erfolgreich getestet worden. Vom 4. bis 9. März 2002 fand in einem Betrieb mit zwei parallel arbeitenden AMS Astronaut(r) in einer Herde von 103 melkenden Kühen die Hauptuntersuchung statt. 4 282 Messungen mit LactoCorder(r) low flow-Geräten an 359 Eutervierteln sind einzeln analysiert worden. Nach Entfernung eventuell fehlerhafter oder nicht eindeutig zuzuordnender Datensätze verblieb eine nutzbare Datenbasis von 2 826 Datensätzen, welche an 195 "unauffälligen" und an 41 "auffälligen" Eutervierteln gemessen worden waren. Die statistische Aufbereitung der absoluten Parameterwerte ergab hoch signifikante Differenzen zwischen "unauffälligen" und "auffälligen" Vierteln für die untersuchten Eingangsvariablen Milchbildungsrate, Milchfluss, Zwischenmelkzeit und Leitfähigkeit. Zur weiteren Modellierung wurden 527 aus den Rohdaten berechnete, normierte Datensätze verwendet, weil diese weitgehend unbeeinflusst von störenden individuellen und Umwelteinflüssen sind. Es sind drei verschiedene Ansätze zur Modellierung der normierten Parameter verfolgt, eingehend analysiert und untereinander sowie mit den Alarmmeldungen der AMS verglichen worden. Während Ein-Parameter-Modelle die höchsten Spezifitätswerte aufzeigten, konnten für die Verknüpfung der vier Eingangsvariablen durch Indexmodelle die besten Sensitivitätswerte ermittelt werden. Das optimale Ergebnis erzielte jedoch die Modellierung mit Hilfe von Fuzzy Logic. Sie ergab mit 5,9 Prozent die niedrigste statistische Wahrscheinlichkeit von Fehlklassifizierungen (falschen Diagnosen). Die Alarmliste der AMS wies zwar eine ähnlich geringe Fehlerquote auf, war jedoch zugleich durch eine schlechte Sensitivität charakterisiert. In einer abschließenden vergleichenden Diskussion mit aktuellen Forschungsergebnissen bestätigte sich die Richtigkeit beider Grundannahmen der vorgelegten Dissertation: 1. Aus Daten des Melkprozesses zu ermittelnde, viertelbezogene Parameter eignen sich zur Ergänzung von Leitfähigkeitsmessungen für die Erkennung von Euterkrankheiten. 2. Fuzzy Logic ist eine handliche und wirkungsvolle Methodik zur Modellierung der Zusammenhänge zwischen Melk- und Milchparametern einerseits und der Eutergesundheit andererseits. / The goal of the work was to examine to what extent the evaluation of the udder health in Automatic Milking Systems (AMS) can be improved by the combination of simply measurable data of the milking process by means of Fuzzy Logic. Own investigations were centred on the evaluation of different milking and milk parameters regarding their suitability as input variable of recognition models for udder diseases as well as on the development and optimisation of Fuzzy Logic models. In the context of a preliminary study, it was examined which variables should form the input of the recognition model. For this purpose, besides the collection of the process data of an AMS Astronaut(r), 754 measurements of single udder quarters were accomplished with measuring devices LactoCorder(r) low flow and were individually processed. The evaluation of this data resulted in certain differences between "inconspicuous" (healthy) and "conspicuous" (more ore less ill) udder quarters regarding the quarter-related parameters milk production rate, milk flow and milking interval which are usable for model building. Also the electrical conductivity should be included into further procedures. The functionality of simple Fuzzy logic models was tested successfully on the basis of 74 generated data sets. The main investigation took place in a dairy farm with two parallel working AMS Astronaut(r) in a herd of 103 milking cows. 4,282 measurements at 359 udder quarters with devices LactoCorder(r) low flow were individually analysed. After removal of possibly incorrect data records or those which could not clearly be assigned remained a usable database of 2,826 records measured at 195 "inconspicuous" and at 41 "conspicuous" udder quarters. The statistic analysis of the absolute parameter values resulted in highly significant differences between "inconspicuous" and "conspicuous" quarters for the examined input variables milk production rate, milk flow, milking interval and electrical conductivity. For the further modelling, 527 standardised data sets computed from the raw data were used because these are largely uninfluenced by disturbing individual and environmental determinants. Three different approaches of model building for the standardised parameters were pursued, analysed and compared among themselves as well as with the alerts of the AMS. While the One-parameter-models pointed out the highest specificity values, the best sensitivity values were determined for the linkage of the four input variables by index-models. However, the optimal result of modelling was obtained by Fuzzy logic. It resulted in the lowest probability of false classifications (wrong diagnoses) with 5,9 per cent. The alarm list of the AMS featured a margin of error which was similar low, however, at the same time it was characterised by bad sensitivity. A concluding discussion with current investigation results confirmed the correctness of both basic assumptions of the dissertation: 1. Quarter-related parameters which can be calculated from data of the milking process are suitable as a complement to conductivity measurements for the detection of udder diseases. 2. Fuzzy Logic represents a manageable and effective methodology for modelling the interrelations between milking and milk parameters on the one hand and the udder health on the other hand.
133

畑作害虫からみる中世の集落景観とAMS^<14>C年代測定

Nakamura, Toshio, Mori, Yuichi, Okuno, Emi, 中村, 俊夫, 森, 勇一, 奥野, 絵美 03 1900 (has links)
第22回名古屋大学年代測定総合研究センターシンポジウム平成21(2009)年度報告
134

Génération de modèles de haut niveau enrichis pour les systèmes hétérogènes et multiphysiques / Generating high level enriched models for heterogeneous and muliphysics systems

Bousquet, Laurent 29 January 2014 (has links)
Les systèmes sur puce sont de plus en plus complexes : ils intègrent des parties numériques, desparties analogiques et des capteurs ou actionneurs. SystemC et son extension SystemC AMSpermettent aujourd’hui de modéliser à haut niveau d’abstraction de tels systèmes. Ces outilsconstituent de véritables atouts dans une optique d’étude de faisabilité, d’exploration architecturale etde vérification du fonctionnement global des systèmes complexes hétérogènes et multiphysiques. Eneffet, les durées de simulation deviennent trop importantes pour envisager les simulations globales àbas niveau d’abstraction. De plus, les simulations basées sur l’utilisation conjointe de différents outilsprovoquent des problèmes de synchronisation. Les modèles de bas niveau, une fois crées par lesspécialistes des différents domaines peuvent toutefois être abstraits afin de générer des modèles dehaut niveau simulables sous SystemC/SystemC AMS en des temps de simulation réduits. Une analysedes modèles de calcul et des styles de modélisation possibles est d’abord présentée afin d’établir unlien avec les durées de simulation, ceci pour proposer un style de modélisation en fonction du niveaud’abstraction souhaité et de l’ampleur de la simulation à effectuer. Dans le cas des circuits analogiqueslinéaires, une méthode permettant de générer automatiquement des modèles de haut niveaud’abstraction à partir de modèles de bas niveau a été proposée. Afin d’évaluer très tôt dans le flot deconception la consommation d’un système, un moyen d’enrichir les modèles de haut niveaupréalablement générés est présenté. L’attention a ensuite été portée sur la modélisation à haut niveaudes systèmes multiphysiques. Deux méthodes y sont discutées : la méthode consistant à utiliser lecircuit équivalent électrique puis la méthode basée sur les bond graphs. En particulier, nous proposonsune méthode permettant de générer un modèle équivalent au bond graph à partir d’un modèle de basniveau. Enfin, la modélisation d’un système éolien est étudiée afin d’illustrer les différents conceptsprésentés dans cette thèse. / Systems on chip are more and more complex as they now embed not only digital and analog parts, butalso sensors and actuators. SystemC and its extension SystemC AMS allow the high level modeling ofsuch systems. These tools are efficient for feasibility study, architectural exploration and globalverification of heterogeneous and multiphysics systems. At low level of abstraction, the simulationdurations are too important. Moreover, synchronization problems appear when cosimulations areperformed. It is possible to abstract the low level models that are developed by the specialists of thedifferent domains to create high level models that can be simulated faster using SystemC/SystemCAMS. The models of computation and the modeling styles have been studied. A relation is shownbetween the modeling style, the model size and the simulation speed. A method that generatesautomatically the high level model of an analog linear circuit from its low level representation isproposed. Then, it is shown how to include in the high level model some information allowing thepower consumption estimation. After that, the multiphysics systems modeling is studied. Twomethods are discussed: firstly, the one that uses the electrical equivalent circuit, then the one based onthe bond graph approach. It is shown how to generate a bond graph equivalent model from a low levelrepresentation. Finally, the modeling of a wind turbine system is discussed in order to illustrate thedifferent concepts presented in this thesis.
135

Metodologia de Verifica??o Funcional para Circuitos Anal?gicos

Fonseca, Adauto Luis Tadeo Bernardes da 04 September 2009 (has links)
Made available in DSpace on 2014-12-17T14:55:40Z (GMT). No. of bitstreams: 1 AdautoLT.pdf: 2061017 bytes, checksum: 12a139ba25174e3b22d08cf31c934500 (MD5) Previous issue date: 2009-09-04 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work proposes a new methodology to verify those analog circuits, providing an automated tools to help the verifiers to have a more truthful result. This work presents the development of new methodology for analog circuits verification. The main goal is to provide a more automated verification process to certify analog circuits functional behavior. The proposed methodology is based on the golden model technique. A verification environment based on this methodology was built and results of a study case based on the validation of an operational amplifier design are offered as a confirmation of its effectiveness. The results had shown that the verification process was more truthful because of the automation provided by the tool developed / O presente trabalho tem como objetivo desenvolver uma ferramenta de verifica??o para circuitos anal?gicos. O principal objetivo desta ? aumentar a automa??o dos processos de verifica??o. Al?m disso, proporcionar a constru??o de um ambiente de verifica??o capaz de gerar relat?rios ao longo deste processo. Esta metodologia ? baseada na t?cnica do Modelo de Ouro, no entanto, ela tamb?m prop?e uma segunda t?cnica para verificar o modelo de refer?ncia, para se obter resultados mais confi?veis. A metodologia foi utilizada, como estudo de caso, na verifica??o de um amplificador operacional
136

Cosmic ray 2H/1H flux ratio measurement with the AMS-02 experiment / Medição da razão 2H/1H de fluxo em raios cósmicos com o experimento AMS-02

Vitor Diorio Lordello 26 September 2017 (has links)
The Alpha Magnetic Spectrometer (AMS-02) is a cosmic ray detector operating aboard the International Space Station (ISS) since May 2011. The identification of cosmic ray deuterium and hydrogen particles is the main goal of this work. Using the data collected by the AMS-02 experiment between May 2011 and May 2014 we provide the measurement of the 2H to the 1H ratio between 0.7 and 7 GeV/n. Cosmic rays are mainly composed of hydrogen nuclei. No significant amount of deuterium nuclei is expected to be released from galactic sources since they are destroyed rather than formed in thermonuclear reactions inside stars. As a consequence of their production history, they are part of a class of secondary stable nuclei that provide information on the propagation of cosmic rays in the galaxy. Despite their relevance for propagation studies, very few measurements of deuterium exist above 1 GeV/n, due to the poor isotopic separation capacity of previous experiments. For this reason, the deuterium to hydrogen flux ratio is a very important measurement to be carried out using the data collected by the AMS-02 experiment. The mass and the isotopic composition of cosmic-rays nuclei can be measured by the AMS-02 experiment using measurements of the momentum (provided by the tracker) and velocity of the particles (provided by the Time-of-Flight and the RICH). This analysis is one of the first to be focused on hydrogen isotopic composition with AMS-02 data, and our results are in fair agreement with a similar and independent analysis that has been carried out within the Collaboration. / O Espectômetro Magnético Alpha (AMS-02) é um detetor de raios cósmicos operando na Estação Espacial Internacional (ISS) desde maio de 2011. O principal objetivo deste trabalho é a identificação de deutério e hidrogênio nos raios cósmicos. Usando dados coletados pelo experimento AMS-02 entre maio de 2011 e maio de 2014 foi medida a razão entre os fluxos de 2H e 1H entre 0.7 e 7 GeV/n. Raios cósmicos são compostos, principalmente, por núcleos de hidrogênio. Não é esperado que fontes galácticas de raios cósmicos liberem uma quantidade significativa de núcleos de deutério, já que eles são destruidos, em vez de formados, nas reações termonucleares no interior de estrelas. Assim, eles fazem parte de uma classe de partículas secundárias estáveis que fornecem informações acerca da propagação de raios cósmicos na galáxia. Apesar da relevância para o estudo da propagação de raios cósmicos, poucas medidas da sua quantidade acima de 1 GeV/n existem, devido à baixa capacidade de separação de isótopos de prévios experimentos. Por isso a razão entre os fluxos de deutério e hidrogênio é uma importante medida a ser feita com os dados do AMS-02. A massa, e portanto a composição isotópica dos raios cósmicos, pode ser medida pelo AMS-02 a partir das medições de momento (realizada pelo tracker) e velocidade (realizadas pelo ToF e RICH). Essa análise é uma das primeiras a focar na composição isotópica do hidrogênio com dados do AMS-02, e os resultados estão razoavelmente em acordo com análises independendes semelhantes realizadas na colaboração AMS.
137

Simulation multi-moteurs multi-niveaux pour la validation des spécifications système et optimisation de la consommation / Multi-engine multi-level simulation for system specification validation and power consumption optimization

Li, Fangyan 29 March 2016 (has links)
Ce travail vise la modélisation au niveau système, en langage SystemC-AMS, et la simulation d'un émetteur-récepteur au standard Bluetooth Low Energy (BLE). L'objectif est d'analyser la relation entre les performances, en termes de BER et la consommation d'énergie du transceiver. Le temps de simulation d’un tel système, à partir de cas d’étude (use case) réaliste, est un facteur clé pour le développement d’une telle plateforme. De plus, afin d’obtenir des résultats de simulation le plus précis possible, les modèles « haut niveau » doivent être raffinés à partir de modèles plus bas niveau où de mesure. L'approche dite Meet-in-the-Middle, associée à la méthode de modélisation équivalente en Bande Base (BBE, BaseBand Equivalent), a été choisie pour atteindre les deux conditions requises, à savoir temps de simulation « faible » et précision des résultats. Une simulation globale d'un système de BLE est obtenue en intégrant le modèle de l'émetteur-récepteur dans une plateforme existante développée en SystemC-TLM. La simulation est basée sur un système de communication de deux dispositifs BLE, en utilisant différents scénarios (différents cas d'utilisation de BLE). Dans un premier temps nous avons modélisé et validé chaque bloc d’un transceiver BT. Devant le temps de simulation prohibitif, les blocs RF sont réécrits en utilisant la méthodologie BB, puis raffinés afin de prendre en compte les non-linéarités qui vont impacter le couple consommation, BER. Chaque circuit (chaque modèle) est vérifié séparément, puis une première simulation système (point à point entre un émetteur et un récepteur) est effectuée / This work aims at system-level modelling a defined transceiver for Bluetooth Low energy (BLE) system using SystemC-AMS. The goal is to analyze the relationship between the transceiver performance and the accurate energy consumption. This requires the transceiver model contains system-level simulation speed and the low-level design block power consumption and other RF specifications. The Meet-in-the-Middle approach and the Baseband Equivalent method are chosen to achieve the two requirements above. A global simulation of a complete BLE system is achieved by integrating the transceiver model into a SystemC-TLM described BLE system model which contains the higher-than-PHY levels. The simulation is based on a two BLE devices communication system and is run with different BLE use cases. The transceiver Bit-Error-Rate and the energy estimation are obtained at the end of the simulation. First, we modelled and validated each block of a BT transceiver. In front of the prohibitive simulation time, the RF blocks are rewritten by using the BBE methodology, and then refined in order to take into account the non-linearities, which are going to impact the couple consumption, BER. Each circuit (each model) is separately verified, and then a first BLE system simulation (point-to-point between a transmitter and a receiver) has been executed. Finally, the BER is finally estimated. This platform fulfills our expectations, the simulation time is suitable and the results have been validated with the circuit measurement offered by Riviera Waves Company. Finally, two versions of the same transceiver architecture are modelled, simulated and compared
138

Modélisation comportementale d'un réseau sur puce basé sur des interconnexions RF. / Behavioral modeling of a network on chip based on RF interconnections.

Zerioul, Lounis 01 September 2015 (has links)
Le développement des systèmes multiprocesseurs intégrés sur puce (MPSoC) répond au besoin grandissant des architectures de calcul intensif. En revanche, l'évolution de leurs performances est entravée par leurs réseaux de communication sur puce (NoC) à cause de leur consommation d'énergie ainsi que du retard. C'est dans ce contexte que les NoC à base d'interconnexions RF et filaires (RFNoC) ont émergé. Afin de gérer au mieux et d'optimiser la conception d'un RFNoC, il est indispensable de développer une plateforme de simulation intégrant à la fois des circuits analogiques et numériques.Dans un premier temps, la simulation temporelle d'un RFNoC avec des composants dont les modèles sont idéaux est utilisée pour optimiser l'allocation des ressources spectrales disponibles. Le cas échéant, nous proposons des solutions pour améliorer la qualité de signal transmis. Dans un deuxième temps, nous avons développé en VHDL-AMS des modèles comportementaux et précis de chacun des composants du RFNoC. Les modèles de l'amplificateur faible bruit (LNA) et du mélangeur, prennent en compte les paramètres concernant, l'amplification, les non-linéarités, le bruit et la bande passante. Le modèle de l'oscillateur local considère les paramètresconventionnels, notamment le bruit de phase. Quant à la ligne de transmission, un modèle fréquentiel précis, incluant l'effet de peau est adapté pour les simulations temporelles. Ensuite, l'impact des paramètres des composants sur les performances du RFNoC est évalué afin d'anticiper les contraintes qui s'imposeront lors de la conception du RFNoC. / The development of multiprocessor systems integrated on chip (MPSoC) respondsto the growing need for intensive computation systems. However, the evolutionof their performances is hampered by their communication networks on chip(NoC) due to their energy consumption and delay. It is in this context that the wired RF network on chip (RFNoC) was emerged. In order to better manage and optimize the design of an RFNoC, it is necessary to develop a simulation platform adressing both analog and digital circuits.First, a time domaine simulation of an RFNoC with components whose modelsare ideal is used to optimize the allocation of the available spectrum resources. Where appropriate, we provide solutions to improve the quality of transmitted signal. Secondly, we have developed, in VHDL-AMS, behavioral and accurate models of all RFNoC components. The models of the low noise amplifier (LNA) and the mixer take into account the parameters for the amplification, nonlinearities, noise and bandwidth. The model of the local oscillator considers the conventional parameters, including its phase noise. Concerning the transmission line, an accurate frequency model, including the skin effect is adapted for time domaine simulations. Then, the impact of component parameters on RFNoC performances is evaluatedto anticipate constraints of the RFNoC design.
139

Iodine Isotopes and their Species in Surface Water from the North Sea to the Northeastern Atlantic Ocean

He, Peng January 2013 (has links)
Huge amounts of anthropogenic 129I have been and still are released to the environment through liquid and gaseous discharges from the nuclear fuel reprocessing facilities worldwide and in particular the ones in Europe. Most of this 129I signal has been accumulated in the marine environment which plays a major role in the iodine natural pool.  In this thesis, an overview of available 129I concentrations in waters of the oceans and marginal seas together with new data about 129I and 127I spatial distribution in surface seawater along a transect between the North Sea and the northeastern Atlantic Ocean are presented. After comprehensive chemical separation, the concentrations of iodine isotopes (127I and 129I) and their species (iodide and iodate) were analysed using accelerator mass spectrometry and inductively-coupled plasma mass spectrometry. The results show that, generally, changes in the 127I and 127I-/127IO3- are comparable to data from other marine waters which are related to natural distribution patterns. A considerable variation of 129I along the transect is observed with the highest values occurring in the eastern English Channel and relatively low values obtained in the northeastern Atlantic Ocean. Inventory estimations of 129I in the North Sea and the English Channel are 147 kg and 78 kg, respectively, where more than 90% resides in the Southern Bight and the eastern English Channel. Iodate is the dominant iodine species for both 127I and 129I in most seawater samples from the North Sea to the Atlantic Ocean. 129I species variability suggests a slow process of 129I- oxidation in the open sea. It takes at least 10 years for the 129I-/129IO3- pair to reach their natural equilibrium as the water is transported from the English Channel. The results suggest a main transport of 129I from the western English Channel via the Biscay Bay into the northeastern Atlantic Ocean. Further, high 129I/127I and distinctive 129I-/129IO3- values south of 40°N indicate possible contribution of 129I through Mediterranean Outflow Water. The environmental radioactive impact of 129I and possible applications in ecosystem studies are also discussed.
140

A Kolmogorov-Smirnov Test for r Samples

Böhm, Walter, Hornik, Kurt 12 1900 (has links) (PDF)
We consider the problem of testing whether r (>=2) samples are drawn from the same continuous distribution F(x). The test statistic we will study in some detail is defined as the maximum of the circular differences of the empirical distribution functions, a generalization of the classical 2-sample Kolmogorov-Smirnov test to r (>=2) independent samples. For the case of equal sample sizes we derive the exact null distribution by counting lattice paths confined to stay in the scaled alcove $\mathcal{A}_r$ of the affine Weyl group $A_{r-1}$. This is done using a generalization of the classical reflection principle. By a standard diffusion scaling we derive also the asymptotic distribution of the test statistic in terms of a multivariate Dirichlet series. When the sample sizes are not equal the reflection principle no longer works, but we are able to establish a weak convergence result even in this case showing that by a proper rescaling a test statistic based on a linear transformation of the circular differences of the empirical distribution functions has the same asymptotic distribution as the test statistic in the case of equal sample sizes. / Series: Research Report Series / Department of Statistics and Mathematics

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