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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.
21

HIGH-FREQUENCY CHARGE-PUMP BASED PHASE-LOCKED LOOP DESIGN AND IT'S CHARACTERIZATION USING VERILOG-AMS

SINGH, GUNEET 02 October 2006 (has links)
No description available.
22

A STUDY OF VHDL-AMS SIMULATION PERFORMANCE AS A FUNCTION OF MODEL COMPLEXITY

GHALI, KALYAN VENKATA 11 October 2001 (has links)
No description available.
23

AN INTEGRATED PETROFABRIC STUDY OF THE HIGH-PRESSURE ORLICA-SNIEZNIK COMPLEX, CZECH REPUBLIC AND POLAND

Pressler, Rebecca E. 08 September 2006 (has links)
No description available.
24

The Formation of Granite Magma Chambers in the Mourne Mountains, Northern Ireland / Bildandet av granitmagmakammare i Mournebergen, Nordirland

Björkgren, Maria January 2017 (has links)
The Mourne Mountains situated in County Down, Northern Ireland, mainly consists of solidified granite magma chambers that intruded ~ 56 million years ago into the surrounding greywacke. How granite magma chambers are emplaced in the crust has for years been a debate amongst scientist of volcanology, and is referred to as the ‘space problem’ debate. There are two principle theories in how the granite magma chambers in the Mourne Mountains were formed; either the magma chambers were forcefully emplaced by doming the greywacke host-rock or the magma chambers were emplaced by passively by magma filling the space over a subsiding block of host-rock. In this study rock samples from Luke’s Mt. dyke has been investigated with anisotropy of magnetic susceptibility (AMS). AMS measures the orientation of magnetic minerals in a rock sample and thereby shows the magma movement. These measurements indicated that the magma in the studied Luke’s Mt dyke flowed into the connected magma chamber and thus are a feeding ring-dyke. This implies that the granite bodies of the Mourne Mountains were emplaced by a passive process like cauldron subsidence. / Mätningar av magnetiska mineral har visat att den stelnade magman i en granitgång tillhörande Mournebergen i Nordirland en gång flödat in mot granitmagmakammarna. Med den här vetskapen kan tolkningar göras över hur de stora Mournebergen en gång formades. Sedan länge har den så kallade ’space problem’ debatten pågått bland forskare inom vulkanologi. Debatten diskuterar huruvida magma intruderar och placeras i jordskorpan. Mournebergen består huvudsakligen av granitmagmakammare som intruderat in i omkringliggande bergarten gråvacka för cirka 56 miljoner år sedan. Är magmakammarna ett resultat av deformation i omkringliggande gråvacka eller tvärtom? AMS (anisotropy of magnetic susceptibility) är en metod där magnetiska mineral och dess magnetiska susceptibilitet mäts för att ta reda på dess orientering i en stelnad magma. Vid ett pålagt magnetiskt fält kommer de magnetiska mineralen visa på en viss magnetisk susceptibilitet i olika orienteringar. Det här kan representeras som tre axlar på en ellipsoid. Axlarna på ellipsoiden ger information om hur mineralen flödat med magman. AMS-mätningar av stenprover från den studerade granitgången Luke’s Mt Dyke i Mournebergen visar på att graniterna som utgör största delen av bergen troligen är resultat av ett så kallat passivt bildande av magmakammare och därmed har omkringliggande bergarten gråvacka inte deformerats av granitmagmakammarna.
25

Magnetická stavba, tok magmatu a tektonická deformace ve vulkano-plutonických systémech / Magnetic fabric, magma flow and tectonic deformation in volcano-plutonic systems

Tomek, Filip January 2015 (has links)
Magnetic fabric, magma flow and tectonic deformation in volcano-plutonic systems ABSTRACT This Ph.D. thesis aims to investigate dynamics of emplacement and tectonic history of selected volcano-plutonic complexes in a continental magmatic arc and back arc setting. The thesis presents new data sets from five field areas, presented in separate chapters, which could be viewed as representing a vertical sections through upper part of an intermediate to felsic magmatic system. From top to bottom in this ‛imaginary' vertical system, the examined units are: (1) andesitic lava domes and (2) sub-volcanic magma chambers (<3 km deep) of the Miocene Štiavnica volcano- plutonic complex, Western Carpathians (Slovakia), (3) Shellenbarger pluton (<3 km depth) within the mid-Cretaceous Minarets caldera, Sierra Nevada batholith in California (USA), and ~7-10 km deep granitoids of (4) Lower-Cretaceous Wallowa batholith, Blue Mountains province in Oregon (USA) and (5) Late Devonian Staré Sedlo complex, central Bohemian Massif (Czech Republic). The research incorporates extensive field and structural data, supported by analysis of igneous textures and anisotropy of magnetic susceptibility (AMS). The latter is further accompanied by detailed examination of magnetic mineralogy using thermomagnetic measurements and optical and back...
26

Mixed-Level-Simulation heterogener Systeme mit VHDL-AMS durch Multi-Architecture-Modellierung

Schlegel, Michael 16 December 2005 (has links) (PDF)
Die Simulation heterogener Systeme auf hoher Abstraktionsebene gewinnt auf Grund der zunehmenden Komplexität technischer Systeme stetig an Bedeutung. Unter heterogenen Systemen versteht man technische Systeme, die aus analoger und digitaler Elektronik, aus Komponenten verschiedener physikalischer Domänen wie mechanischen Strukturen, thermischen und optischen Komponenten sowie aus Software bestehen können. Genügte es bisher, die einzelnen Komponenten für sich in ihrer eigenen Domäne mit einem speziellen Simulator zu simulieren, so ist es heute unerläßlich, auch die Interaktionen zwischen den Komponenten zu erfassen. Um solche Systeme mit einer einheitlichen Beschreibungsform erfassen zu können, entstand aus der digitalen Hardwarebeschreibungssprache VHDL die Systembeschreibungssprache VHDL-AMS. Bei der Modellierung eines Systems muß das tatsächliche Verhalten der Komponenten abstrahiert werden, um mathematisch erfaßbar und in begrenzter Zeit simulierbar zu sein. Der Grad der Abstraktion beeinflußt jedoch die Genauigkeit der Simulationsergebnisse wesentlich. Dabei muß bzw. kann das Verhalten in unterschiedlichen Komponenten unterschiedlich stark abstrahiert werden, um noch akzeptable Simulationsgenauigkeiten erzielen zu können. VHDL-AMS erlaubt die Beschreibung von Komponenten auf unterschiedlichen Abstraktionsniveaus. Man kann die unterschiedlich abstrakten Modelle der Komponenten aber nur schwer in einer Systemsimulation gemeinsam simulieren, da unterschiedlich abstrakte Modelle auch unterschiedlich abstrakte Schnittstellen aufweisen, so daß die Modelle nur mühsam miteinander verbunden werden können. Ein Austausch eines abstrakten Modells einer Komponente gegen ein weniger abstraktes Modell oder umgekehrt ist mit vielen fehleranfälligen und zeitaufwendigen Anpassungsschritten verbunden. Im Rahmen dieser Arbeit wird ein methodischer Ansatz vorgestellt, der es auf der Basis einer Vereinheitlichung der Modellschnittstellen ermöglicht, unterschiedlich abstrakte Modelle gemeinsam zu simulieren und einzelne Modelle gegen abstraktere oder weniger abstrakte Modelle ohne nennenswerten Zeit- und Modellierungsaufwand auszutauschen. Es werden die zu verwendenden Interfaceobjekte und Datentypen für digitale, analoge elektrische und nichtelektrische Schnittstellen unter VHDL-AMS und SystemC-AMS vorgestellt. Ebenso werden Methoden vorgestellt, die digitales, ereignisdiskretes Verhalten auf konservative elektrische Schnittstellen bzw. nichtkonservatives analoges Verhalten auf digitale Schnittstellen abbilden. Weiterhin wird erläutert, wie sich digitale Protokolle über Abstraktionsebenen hinweg übertragen lassen und ein modifizierter Top-Down Design-Flow vorgestellt. Die Demonstration der Anwendbarkeit der Methode erfolgt anhand eines Beispiels.
27

Samvetsgrannhet: Nyckeln till akademisk motivation? : En studie om förhållandet mellan personlighet och akademisk motivation hos studenter på en högskola i Mellansverige.

Sandberg, Emil, Ternström, Simon January 2015 (has links)
The purpose of this study was to investigate the relationship between students’ academic motivation and personality in different classes at a university in central Sweden. The study was conducted on students of economics and nursing, who were asked to answer a paper questionnaire. The questionnaire of consisted two parts, the first part was a TIPI test which measured personality traits using the Big Five theory and the second part was an AMS test that measured academic motivation. A total of 106 students participated in the study, including 50 from economics and 56 from nursing. The main result showed that the strongest significant correlation was between the personality trait conscientiousness and internal motivation. This relationship was found to completely rely on the nursing students replies, giving an indication that the nursing students who were self-disciplined and targeted were motivated by internal factors. This relationship was not found in the replies from the economics students. There was some difference between the two study specializations. / Syftet med studien var att undersöka förhållandet mellan akademisk motivation och personlighet hos studenter med olika studieinriktningar på en högskola i Mellansverige. Studien genomfördes på studenter från ekonom- och sjuksköterskeprogrammet som fick besvara en pappersenkät. Enkäten bestod av två delar, varav den första var ett TIPI-test som mätte personlighetsdimensioner med hjälp Big Five-teorin och den andra var ett AMS-test som mätte akademisk motivation. Totalt deltog 106 studenter i undersökningen, varav 50 från Ekonomprogrammet och 56 från Sjuksköterskeprogrammet. Huvudresultatet visade att det starkaste signifikant sambandet var mellan personlighetsdimensionen samvetsgrannhet och intern motivation. Detta samband visade sig helt bäras av sjuksköterskestudenternas svar, vilket gav en indikation på att de sjuksköterskestudenter som var självdisciplinerade och målinriktade motiverades av interna faktorer. Detta samband återfanns över huvudtaget inte hos ekonomstudenterna. Det förelåg en viss skillnad mellan de två olika studieinriktningarna.
28

Propuesta de reducción de los tiempos de viaje vehicular en el óvalo ubicado en la intersección de la Av. Alfredo Mendiola – Av. Eduardo de Habich, a través del sistema de semaforización inteligente RAMP meter / Proposal for reduction of vehicle travel times in the roundabout located on the intersection Alfredo Mendiola Av. – Eduardo de Habich Av. through RAMP meter singal control smart system

Mariluz Cuadros, Luis Eduardo 26 February 2020 (has links)
La congestión vehicular en Lima es caótica dada la escaza infraestructura vial y el acelerado aumento del parque automotor. En contraste, esta investigación propone implementar el sistema de semaforización inteligente, Ramp Meter, basado en el algoritmo AMS-AG, para reducir los tiempos de viaje vehicular en el óvalo Habich, ubicado en el distrito de San Martín de Porres. La metodología propuesta consta en la recolección de datos estáticos y registro de una lista de verificaciones. Luego se procede con la toma de datos de entrada para construir el modelo, tales como; flujos, velocidades y tiempos de viaje. El primer paquete de datos es utilizado para la construcción y calibración del modelo en el software de microsimulación PTV Vissim 9.0, y el segundo para la validación del modelo. De acuerdo con los resultados de los parámetros de performance vehicular (demora, tiempo de viaje y velocidad) y peatonal (tiempo de viaje, velocidad) de la situación actual y lista de verificaciones, se realiza la propuesta de solución. Del mismo modo, a una proyección a 15 años se estima su funcionalidad en el mediano plazo. Se concluye que la propuesta de mejora a través de la implementación del Ramp Meter, basado en el algoritmo AMS-AG, ofrece mejoras en relación con el performance vehicular, sin embargo, pierde rendimiento a medida que incrementa el flujo vehicular. Cumple con el objetivo principal de la investigación de reducirse los tiempos de viaje vehicular. Por último, se afirma que la inversión económica que demanda es una alternativa viable y rentable. / Vehicle congestion in Lima is chaotic given the lack of road infrastructure and the rapid increase in the number of vehicles. In contrast, this research proposes to implement the intelligent traffic light system, Ramp Meter, based on the AMS-AG algorithm, to reduce vehicle travel times at the Habich roundabout, in San Martin de Porres district. The proposed methodology consists of the collection of static data and registering a checklist. Then, we proceed with taking input data to build the model, such as flows, speed and travels times. The first data packet is used for the construction and calibration of the model in the PTV Vissim 9.0 microsimulation software, and the second one is used for model validation. According to the results of the parameters of vehicular performance (delay, travel time and speed) and pedestrian (travel time and speed) of the current situation and checklist, the proposed solution for roundabout is made. Similarly, at a projection to 15 years its functionality is estimated in the medium term. It is concluded that the improvement proposal through the implementation of the Ramp Meter, based on the AMS-AG algorithm, offers improvements in relation to vehicle performance, however, it loses performance as vehicle flow increases. It fulfills the main objective of the research to reduce vehicle travel times. Finally, it is stated that economic investment that it demands is viable and profitable alternative. / Tesis
29

The influence of teat wash failure on milk yield in dairy cows

Lilja, Mathias, Keteris Eckerstedt, Ilse January 2016 (has links)
Data for the period 2015-04 to 2015-09 was analyzed in order to examine the possible relationship between teat wash failure and the result on milk yield for dairy cows. Data provided by Sveriges Lantrbruksuniversitet over 49 093 specific milking events were used. Two linear mixed-effects models and one basic OLS-model were estimated. In order to perform the analysis a lot of data manipulation also had to be performed. The data analysis was divided into to two parts. First the variable of interest (teatwash) was examined by constructing two versions of the different models; an unrestricted- and a restricted version were teatwash had been excluded. Because of the large sample and linear mixed-effect models an out-of-sample forecasting method was used as the primary evaluation criteria. The prediction errors were evaluated on the basis of root mean squared error (RMSE) and mean squared error (MSE). The difference between the unrestricted- and restricted models was very small and no indication of a relationship between teat wash failure and milk yield was found. The second part involved the comparison of prediction errors between the two mixed-effect models and the OLS-model. Surprisingly, the basic OLS-model resulted in the lowest prediction error although obvious breach of assumptions.
30

Simulation et détection du rayonnement cosmique : Production d'antimatière dans l'atmosphère et étude de l'imageur Cherenkov annulaire de l'expérience AMS

Baret, Bruny 12 October 2004 (has links) (PDF)
Cette thèse porte sur l'étude du rayonnement cosmique nucléaire chargé d'énergie comprise entre quelques centaines de MeV et 1~TeV. Celle-ci peut apporter des réponses à des questions aussi fondamentales que l'asymétrie entre matière et antimatière primordiales, la nature de la matière sombre ou la propagation du rayonnement cosmique. L'étude de ces phénomènes passe par la détection d'antimatière légère. Or l'interaction du rayonnement cosmique primaire au voisinage de la terre conduit à la production et au piégeage de particules secondaires, dont des noyaux légers d'antimatière. Ce travail vise à caractériser cette dernière composante de bruit physique pour des expériences ballons ou satellites. Ceci a été mené à bien grâce à une simulation Monte-Carlo tridimensionnelle prenant en compte de manière réaliste les interactions nucléaires. Cette étude montre en particulier l'importance du phénomène de piègeage magnétique et de l'interaction inélastique non-annihilante pour les particules présentes à 400~km d'altitude. La deuxième partie porte sur l'étude de l'imageur annulaire Cherenkov de l'expérience AMS qui permettra d'effectuer une séparation isotopique du rayonnement cosmique nucléaire chargé. La résolution en vélocité du détecteur a donc été étudiée lors de tests cosmiques et sous faisceau. Il en ressort que le détecteur est compris et que ses performances sont conformes aux attentes. Enfin, un travail de simulation prenant en compte le trigger et l'efficacité de détection d'AMS a été entrepris sur le rapport isotopique $^(10)$Be/$^(9)$Be qui montre les capacités d'AMS pour la contrainte des paramètres astrophysiques de propagation du rayonnement cosmique.

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