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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.
351

Dynamic Load Generator: Synthesising dynamic hardware load characteristics

Karlsson, Stefan, Hansson, Erik January 2015 (has links)
In this thesis we proposed and tested a new method for creating synthetic workloads. Our method takes the dynamic behaviour into consideration, whereas previous studies only consider the static behaviour. This was done by recording performance monitor counters (PMC) events from a reference application. These events were then used to calculate the hardware load characteristics, in our case cache miss ratios, that were stored for each sample and used as input to a load regulator. A signalling application was then used together with a load regulator and a cache miss generator to tune the hardware characteristics until they were similar to those of the reference application. For each sample, the final parameters from the load regulator were stored in order to be able to simulate it. By simulating all samples with the same sampling period with which they were recorded, the dynamic behaviour of the reference application could be simulated. Measurements show that this was successful for L1 D$ miss ratio, but not for L1 I$ miss ratio and only to a small extent for L2 D$ miss ratio. We were also able to show that the total convergence time for the regulator could be reduced by using case-based reasoning to select the initial parameters from similar samples.
352

Synthèse de règles de sécurité pour des systèmes autonomes critiques / Synthesis of safety rules for critical autonomous systems

Machin, Mathilde 12 November 2015 (has links)
Les systèmes autonomes, notamment ceux opérant à proximité d'êtres humains, soulèvent des problèmes de sécurité-innocuité puisqu'ils peuvent causer des blessures. La complexité de la commande de ces systèmes, ainsi que leurs interactions avec un environnement peu structuré, rendent difficile l'élimination complète des fautes. Nous adoptons donc une démarche de tolérance aux fautes en considérant un moniteur de sécurité séparé de la commande principale et qui dispose de ses propres moyens d'observation et d'intervention. Le comportement de ce moniteur est régi par des règles qui doivent assurer la sécurité du système tout en lui permettant de remplir ses fonctions. Nous proposons une méthode systématique pour obtenir ces règles de sécurité. Les dangers, déterminés par une analyse de risque, sont modélisés formellement puis un algorithme synthétise des règles sûres et permissives, s'il en existe. Nous avons outillé cette méthode pour les étapes de modélisation et de synthèse en nous appuyant sur l'outil de vérification de modèle NuSMV. L'étude d'un cas industriel illustre l'application de la méthode et des outils sur un robot manufacturier dans un environnement humain. / Autonomous systems operating in the vicinity of humans are critical in that they potentially harm humans. In these systems, fault removal is not sufficient given the command complexity and their interactions with an unstructured environment. By a fault tolerance approach, we consider a safety monitor separated from the main command and able to observe and intervene on the system. The monitor behavior is specified by safety rules that must both ensure safety and permit the system to carry out its tasks in absence of hazard. We propose a systematic method to obtain these safety rules. The hazards, determined by a risk analysis, are formally modeled, then an algorithm synthesizes safe and permissive rules, if any exists. The method is tooled both for modeling and synthesis by use of the model-checker NuSMV. Method and tools are applied to the industrial use case of a robotic co-worker.
353

Messagingová infrastruktura a produktová analýza trhu / Message infrastructure and market analysis

Klimeš, Ivo January 2008 (has links)
There are considered modern messaging architectonical concepts SOA and EDA in this diploma thesis. There are presented the elementary principals of functioning of these paradigms and principals are given into the wider context with the business processes and IT Governance. The aim of this thesis is to compare two preselected software solutions of the operational monitoring. There is always one solution per architectonical style and predefined comparative criteria. This thesis is divided into five consequential parts. The first part is focused on the putting the modern architectures into the historical context. The historical context is the way out for the modern architectonical styles. The part afterwards is closely focused on the concepts of SOA and EDA, and also on the comparison of the mentioned architectonical styles. There are put the concepts into the connection with business processes and maturity models In the next chapters. That all together has a influence on the successful implementation and governance. The chapters continuously flow into the last theoretical part of the thesis, IT Governance. There are described all the elements connected with the successful IT systems operating based on the paradigm SOA or EDA. The context in the practical part is link to the all these previous chapters. There are selected and described two software solutions in the practical part of this thesis. These solutions are then compared by the predefined criteria. The conclusion summarizes all the knowledge acquired during the paradigm comparison and there are also summarized knowledge acquired during the comparison of selected monitoring products.
354

Analýza souvislostí mezi self-efficacy, kapitálem, plánováním a ambicemi začínajících podnikatelů v České republice / Analysis of the link between self-efficacy, capital, planning and ambition of nascent entrepreneurs in the Czech Republic

Mareš, Jan January 2011 (has links)
The thesis is based on data from the Global Entrepreneurship Monitor project and analyzes the link between self-efficacy of Czech nascent entrepreneurs and the disposable amount of human, social and financial capital. It also examines the link between self-efficacy and planning activities of nascent entrepreneurs. The second part of the paper analyzes the relationship between growth ambitions of nascent entrepreneurs and disposable human, social, financial capital and business planning. It also shows the relationship between entrepreneurial self-efficacy and growth aspirations of Czech nascent entrepreneurs.
355

Uso do espalhamento de luz para o estudo do efeito de uréia sobre agregados supramoleculares e monitoramento do peso molecular em reações de polimerização / Use of light scattering to study the effect of urea about supramolecular aggregates and monitoring of the molecular weight in polymerization reactions

Fábio Herbst Florenzano 18 June 1999 (has links)
Nesta tese, dois projetos distintos que usaram a técnica do Espalhamento de Luz foram desenvolvidos. Estudou-se a influência de soluções concentradas de uréia sobre agregados supramoleculares de anfifilicos (ASA\'s), através de condutimetria, supressão de fluorescência e espalhamento de luz. A uréia causou aumento da concentração micelar crítica (CMC) em todos os sistemas micelares estudados. A uréia diminuiu a seletividade da ligação iônica entre cloreto e brometo em micelas de haleto de cetil-trimetil-amônio, estudada através de supressão de fluorescência. Este aditivo causou também aumento na segunda CMC de brometo de tetradeciltrimetil- amônio (TTAB) e diminuição do peso molecular das micelas em bastão formadas. Concluiu-se, desta primeira parte, que a uréia tende a interferir nas transições de fase apresentadas em sistemas micelares, provavelmente através da combinação dos mecanismos direto e indireto. A uréia apresenta potencial para uso como aditivo para modulação das propriedades estruturais de sistemas micelares. Na segunda parte da tese desenvolveu-se um sistema, baseado em espalhamento de luz, capaz de monitorar o peso molecular de polímeros durante a polimerização. O sistema foi eficiente no monitoramento da polimerização da N-vinil-pirrolidinona, mostrando que o peso molecular do polímero formado é constante durante a maior parte da reação. As teorias atuais de cinética de polimerização não foram capazes de explicar esse comportamento. / Light scattering techniques (static and dynamic) were used to detenninate the effect of urea on supramolecular aggregates and to monitor on-line molar mass ofpolymerization reactions. For the first set of investigation it was already established that urea increases the CMC and the dissociation degree (α) of ionic micelles (CTABr, TTABr, and SDS). From fluorescence suppression studies it was found that urea diminishes the ionic binding in zwitterionic and cationic micelles as well as in cationic vesicles. Bromide and chloride ionic selectivity in cationic micelles was found to nearly disappear in the presence of urea. Light scattering (static) detenninations showed that the weight averaged molecular weight (Mw) ofboth SDS and CTABr are invariant by the presence of the denaturant. A slight increase in the excluded volume tenn (A2) was detected for CTABr in the presence of 3M urea. In parallel both A2 and the radius of gyration (γ) of two polyelectrolytes (PAA and Hyaluronic acid) were not affected by the presence of urea. Sphere-to-rod concentration transitions (2nd CMC) of TIABr micelles increased in the presence of urea and the MW of rod particles were observed to decrease. For the insoluble mixture of CTABr/Polystyrenesulfonate solubilization was achieved in the presence of 3M urea. These set of results were explained as a result of the dual effect of urea, that is, the indirect effect by changing the properties of the solvent and the direct effect by solvating the hydrophilic domain of the aggregates and contributing with a stronger dipole moment. The second set of experiments was directed towards the real-time, on-line monitoring of Mw of polymerization reactions. This new approach could be succeeded by the coupling a light scattering detector, an UV photometer and a differential refractometer on line with a HPLC system. Mw growth formed in the polymerization of N-vynil-pirrolidone was accomplished with a small inherent error. Within the studied conditions Mw reached a plateau at early polymerization stages, after that only an increase in the number of polymer kinetic chains was observed. Current kinetic models were unable to predict the observed Mw growth pattern. This system is of great importance in basic and technological applications by virtue of its on-line capability.
356

Etude de faisabilité d'un détecteur dédié à la discrimination bêta/gamma / Study of the feasibility of a detector dedicated to the beta/gamma discrimination

Luo, Yiyan 04 December 2018 (has links)
A des fins de propreté radiologique, les exploitants nucléaires doivent évaluer l'activité surfacique résiduelle, telle que la contamination bêta. Pour cela, les contaminamètres sont essentiels. Dans ce cadre, EDF R&D a proposé un projet de recherche visant à étudier la faisabilité d’un contaminamètre innovant permettant de détecter l’activité surfacique bêta in situ, alors qu’elle est actuellement mesurée ex-situ.L'objectif principal de ce travail est de détecter une contamination bêta surfacique de 0,4 Bq/cm^2 dans un environnement gamma élevé, jusqu'à 100 µSv/h. Cela exige un détecteur ayant une performance de discrimination bêta/gamma élevée. Plusieurs technologies basées sur un scintillateur et/ou un détecteur à gaz ont été étudiées. Des simulations Geant4 ont été effectuées pour optimiser la configuration des technologies retenues (géométrie, matériaux, etc.). Suite à ces simulations, deux prototypes, de type Phoswich, optimisés ont été fabriqués et testés à l’aide de sources bêta et gamma au laboratoire ( LPC Caen). En outre, deux campagnes d’essai ont été menées dans une centrale nucléaire (CNPE de Chinon) afin d'évaluer les performances des prototypes développés dans un bruit de fond gamma réaliste. Les simulations Geant4 et les tests sont discutés dans cette thèse. / For radiological cleanliness purpose, nuclear operators have to assess surface residual activity such as beta contamination. To this aim, contamination monitors are essential. In this context, EDF R&D proposed a research project in order to study the feasibility of an innovative contamination monitor to detect beta surface activity in situ which is until now performed ex situ. The main objective is to detect a 0.4 Bq/cm^2 beta surface contamination in a high gamma background up to 100 μSv/h. This demands the detector to have a high beta/gamma discrimination performance. Several technologies based on scintillator and/or gas filled detector have been investigated. Geant4 simulations have been carried out to optimise the configuration of the chosen detector such as geometry, materials, etc. Two simulation-optimised prototypes based on Phoswich detectors have been developed and tested with beta and gamma sources in a laboratory framework (LPC Caen). Furthermore, two experimental campaigns have been conducted in a nuclear power plant (NPP of Chinon) in order to evaluate the performance of the developed prototypes in a realistic gamma background environment. The Geant4 simulations and the experimental work are discussed in this thesis.
357

Vnímání textu z tištěné předlohy a obrazovky / Reader's perception of printed and displayed text

Piskáčková, Klára January 2016 (has links)
(in English): This thesis is conceived as a metareview of research on differences in perception, understanding and retention of text on various display media. It summarizes the results of the most interesting and most relevant research on this topic conducted since the 80s to the present. Even though it is difficult to summarize the results of individual studies, mainly because of differences in research methodology and differently chosen tested samples, we can say that the main finding of this metareview is that display technologies that are available these days have no negative effect on eye fatigue, reading speed, perception, understanding or retention of text. Theoretical part of this thesis is followed by practical part that consists of three short experiments performed on a small sample of participants. First of those experiments studies differences in reading comprehension and retention among high school students, second experiment focuses on differences in reading speed on different media and subjective evaluation of eye fatigue, and the third experiment is an online form about subjective preferences of study materials among learners.
358

Untersuchungen zur Einsatzmöglichkeit der Dreikantmuschel Dreissena polymorpha als biologischer Filter und Wasserhygienemonitor

Schröter-Bobsin, Ute 25 April 2005 (has links)
Dreikantmuscheln (Dreissena polymorpha) sind aufgrund ihrer speziellen Ernährungsweise in der Lage, erhebliche Wassermengen unterschiedlichster Qualität sehr effektiv zu filtrieren und dabei zu reinigen (Biofilter). Ziel der Arbeit waren Einschätzungen zum Leistungsumfang, der Nutzung und von Grenzen des Muschelfilters. Die Exposition der Muscheln erfolgte in der Elbe am Neustädter Hafen in Dresden (Oberflächengewässer), in dem ersten und zweiten Schönungsteich der Kläranlage Reichenau (Sachsen) und in einem Waldbad in Langebrück (Badegewässer). Eine wirksame Elutionsmethode war die Grundlage um Mikroorganismen (Bakterien, Viren und Parasiten) aus dem Muschelgewebe effizient nachweisen zu können. Die bakterielle Wiederfindungsrate von 86% und eine Wiederfindung von 97% für Bakteriophagen bestätigen die Elutionseffizienz des Verfahrens. Die Befähigung von Dreissena polymorpha zu einer saisonal beeinflussten Bioakkumulation gegenüber dem Umgebungswasser konnte durch ein Monitoring mit einem Anreicherungsfaktor für Bakterien von 87 (gemittelt) und für Bakteriophagen von 261 (gemittelt) eindrucksvoll bestätigt werden. Batchversuche im Labormaßstab bestätigten die im in situ - Monitoring ermittelte Bakterienakkumulation und demonstrieren darüber hinaus eine temperaturabhängige Inaktivierung (Elimination) der Bakterien (Intestinale Enterokokken) durch die Muscheln mit Reduktionsraten von -77% bei 20°C bzw. -61% bei 6°C. Nicht alle aufgenommenen Organismen werden durch die Muscheln inaktiviert. Das ergaben die in situ Sedimentuntersuchungen unter dem Muschelfilter. Die Verdopplung der Enterokokken sowie die erhöhten Werte der somatischen Coliphagen im Sediment unter Muschelbesatz charakterisieren dieses Kompartiment als Keimreservoir. Die bakterielle Besiedlung des Verdauungstraktes von Dreissena polymorpha wird stark durch die Bakterienzönose des umgebenden Wassers beeinflusst. Sowohl im Wasser als auch im Muschelgewebe dominierten fünf Bakterienstämme (Actinobacteria, Proteobacteria, Bacteroidetes, Firmicutes,"environmental group"). Eine auffallend hohe Dominanz zeigten die Mycoplasmen (Firmicutes), was auf eine mögliche ökologische Nische für Vertreter dieser Gattung in der Muschel hindeutet. In allen Muscheleluaten des Monitorings wurden Legionellen nachgewiesen. Die Muscheln des Teiches 2 der KA Reichenau zeigten mit 86% die höchste Kontamination aller Expositionsorte. Legionellenamplifikate im Muscheleluat 2 gingen kontinuierlich mit ebenfalls positiven Befunden im Wasser einher, so dass der Einsatz von Dreissena polymorpha auch im Biomonitoring von Legionellaceae möglich ist. Erstmalig wurden in der Elbe und im Abwasser der KA Reichenau E. coli O157:H7 infizierenden Phagen und deren Anteile nachgewiesen. Die Elbe lag mit einem E. coli O157:H7 infizierenden Phagenanteil von 7,5% deutlich über dem Rohabwasser (1,0%) und dem Zulauf zum ersten Schönungsteich der Kläranlage (0,5%). Der Stx Gennachweis im Muscheleluat war dagegen nur in einer von 24 Proben erfolgreich. Enterale Viren (AdV, EV) wurden in den Dreikantmuscheln und ihrem Umgebungswasser diskontinuierlich nachgewiesen. Enteroviren wurden im Wasser (57% gemittelt) häufiger als in der parallelen Muschelproben (10%) nachgewiesen. Parasiten (Giardia lamblia und Cryptosporidium parvum) werden durch die exponierten Muscheln aufgenommen, dies bestätigten die qualitativen Testergebnisse. In den Dreikantmuscheln wurde sowohl für G. lamblia (78%), als auch für Cryptosporidien (77%) eine durchschnittlich höhere Nachweisrate im Vergleich zu den korrespondierenden Wasserproben (42% und 36%) ermittelt. Die effiziente Akkumulation und die Umweltresistenz der Dreikantmuscheln sind hervorragende Eigenschaften, die sich zu einem zuverlässigen Biomonitor mit "Hygienegedächtnis" und hoher Sensibilität vereinen lassen.
359

Development and Integration of a Low-Cost Occupancy Monitoring System

Mahjoub, Youssif 12 1900 (has links)
The world is getting busier and more crowded each year. Due to this fact resources such as public transport, available energy, and usable space are becoming congested and require vast amounts of logistical support. As of February 2018, nearly 95% of Americans own a mobile cell phone according to the Pew Research Center. These devices are consistently broadcasting their presents to other devices. By leveraging this data to provide occupational awareness of high traffic areas such as public transit stops, buildings, etc logistic efforts can be streamline to best suit the dynamics of the population. With the rise of The Internet of Things, a scalable low-cost occupancy monitoring system can be deployed to collect this broadcasted data and present it to logistics in real time. Simple IoT devices such as the Raspberry Pi, wireless cards capable of passive monitoring, and the utilization of specialized software can provide this capability. Additionally, this combination of hardware and software can be integrated in a way to be as simple as a typical plug and play set up making system deployment quick and easy. This effort details the development and integration work done to deliver a working product acting as a foundation to build upon. Machine learning algorithms such as k-Nearest-Neighbors were also developed to estimate a mobile device's approximate location inside a building.
360

Sensorkaraktärisering kring delaminering

Paul, Sanjib January 2020 (has links)
Dagens industrier håller på att bli allt mer automatiserade, smartare och effektivare, i samband med detta ökas kraven att man tar fram noggrannare och pålitligare sensorsystem som är även kostnadseffektiva. Målet med denna undersökning har varit tillsammans med Iggesund Pappersbruk är att karakterisera noggrannheten för sensorn Ultrasonic Double sheet moniter (DSM) och även ta fram riktlinjer för en ingående inline mätande prototyp. Studien använder sig av väldigt enkla metoder för att karakterisera resolutionen och även undersöka det minimala avståndet för flera seriekopplade sensorer utan att de ingriper och stör varandras inläsningar. De programvaror som används under studien är PACTware och Matlab. Undersökningen visar resultat på en trovärdig noggrannhet utav sensorn och man har även kunnat karakteriserat detektions arean runt om receivern för den framtida prototypen. Avslutningsvis går studien igenom synpunkter på DSM sensorn och en diskussion om att karakterisa olika destruktiva ytor men även om vad som kan förbättras eller förbyggas. / Today's industries are becoming more automated, smarter and more efficient, and it requires high standards to develop more accurate and reliable sensor systems that are low-cost. The aim of this study was together with Iggesund Pappersbruk to characterize the accuracy of the Ultrasonic Double Sheet Monitor (DSM) sensor and to develop guidelines for an in-line measuring prototype. The study uses quite simple methods to characterize the resolution and investigate the minimum distance for several series-connected sensors without interfering with each other's readings. The software used during the study is PACTware and Matlab. The study shows results on a credible accuracy of the sensor and it has also been possible to characterize the detection area around the emitter for the future prototype. Finally, the study concludes with views on the DSM sensor and a discussion on how to characterize different destructive surfaces but also what can be improved or prevented.

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