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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.
701

Digitalizovaný experiment - prostředek k osvojení vybraného učiva obecné chemie / Digitized experiments - The instrument for mastering of selected curriculum of general chemistry

Bartoš, Ivan January 2010 (has links)
By analyzing electronical tools, online applications and tutorials from Czech Republic and abroad I have come to the conclusion that it is necessary to create a flexible educational instrument which includes digitized chemical experiments for general chemistry. Following the analysis of present databases, CD ROMs and VHS containing pictured experiments I found out that a lot of spectacular experiments with pyrotechnical components have not been shooted at all or not in the range of "greater" chemicals quantity. The chosen programming language, in which FMDP was written, proved to be most efficient. This choice emerged from a discussion with programmers and was motivated in particular by larger possibilities of C# than HTML have. In addition to it the modification of the FMDP content is easy. The teachers with minimum of the PC-literacy can make any changes in FMDP, alternate any of its parts and adapt them for various internal and external conditions of education. With regard to the interview having found the needs of learners I filmed and digitized especially such experiments that present the chemical reactions accompanied by the rise of a smoke, light emission, explosion and a surprising turn of colours. On the basis of the statistical evaluation of statistical data containing marks achieved by...
702

Okolnosti vylučující protiprávnost a činnost lékaře / Circumstances of justification and medical practise

Strnad, Jan January 2013 (has links)
Responsibility of the doctor in criminal law and the circumstances under which it is possible to carry out medical procedures without the threat of legal punishment is a topic that has been, is and will be always up to date. It is a complex set of problems, which includes aspects of moral, medical and legal. In my thesis I focused on relationship between doctor's proffession and legal aspects of his work according to criminal law. Its goal is to describe the issue of the practice of medicine and circumstances of justification in terms of legislation in the Czech Republic. The thesis consists of three chapters. The first chapter provides an introduction to the problem and the reasons that led me to choose this topic work. The second chapter is devoted to criminal liability and is divided into two parts. The first contains the general conditions that are necessary for criminal liability of doctors. The second part contains the typical and most common possible crimes that may physician in the exercise of their profession commit. The third and most extensive chapter has focused on description of the circumstances of justification. The chapter is divided into four parts. Firstly it deals with self-defense and legitimate use of weapons that are not too common in the medical environment. Then I focus on...
703

Ochrana člověka za mimořádných událostí jako téma pro žáky středních odborných škol / Human Protection in Emergencies as a Theme for Vocational School Students

Metelková, Iva January 2014 (has links)
TITLE: Human Protection in Emergencies as a part of Health Education AUTHOR: Iva Metelková DEPARTMENT: Department of Education SUPERVISOR: PaedDr. Eva Marádová, CSc. ABSTRACT Human Protection in Emergency (HPE) is the subject of this theoretical research thesis. The theoretical part focuses on a set of human protection in emergency and military training in the broader historical context but also legislative context. Space is devoted to the unambiguous definition of related terms. Furthermore the course curriculum reform with emphasis on the level of secondary vocational education. The practical part is focused on the evaluation of the research that was conducted among the students of first and second years of nonscience oriented secondary vocational schools. Data for the research was obtained by questionnaire survey and analyzed the statistical method. The work also includes a draft concept for the implementation of the teaching of human protection in emergencies. The objective of this proposal is to ensure access to information concerning the HPE for students but also for teachers and that contribute to the formation of desirable patterns of behavior for participation in the incident. KEY WORDS: emergency event, protection of man, military training, vocational education, comparison, chemical experiment
704

Studium precese magnetizace v materiálech a strukturách pro spintroniku / Studium precese magnetizace v materiálech a strukturách pro spintroniku

Kašpar, Zdeněk January 2016 (has links)
In this thesis we studied precession mechanism in ferromagnetic thin film half-metal NiMnSb. We measured magnetization oscillations using optical pump and probe experiment at temperatures between 15 and 200 K and we evaluated the magnetic anisotropy fields, spin stiffness and Gilbert damping. New setup for ferromagnetic resonance measurement was built utilizing vector network analyser. With this setup we measured FMR at temperatures between 300 and 75 K. We evaluated the same parameters from FMR experiments as from the optical one. We found very good agreement in results obtained by the two methods. Powered by TCPDF (www.tcpdf.org)
705

Effect of the Flat Tax Reform on Labour Supply Elasticity at the Intensive and Extensive Margins: Evidence from the Czech Republic / Effect of the Flat Tax Reform on Labour Supply Elasticity at the Intensive and Extensive Margins: Evidence from the Czech Republic

Tomo, Ján January 2015 (has links)
The thesis deals with the estimation of labour supply responses to the personal income tax reform in the Czech Republic adopted in 2008 by applying quasi experimental design known as "difference-in-differences". By exploiting the different change in the effective tax rates for various population subgroups as a natural experiment and using microdata from European Labour Force Sur- vey we constructed the treatment and control groups according to the highest attained level of education serving as a proxy for an income range that assigns an individual to the particular tax bracket before and after policy change. Analysing one-person households we found significant negative effect on the labour force participation and significant positive effect on the hours work of the treated by comparing these outcomes for the treatment and control groups in the baseline and follow up periods before and after the reform. JEL Classification C21, D04, H24, H31, I38, J22 Keywords tax reform, labour supply, natural experiment, difference-in-differences Author's e-mail janxtomo@gmail.com Supervisor's e-mail gebicka@fsv.cuni.cz
706

Evoluce antisociálního trestání / The Antisocial Punishment Evolution

Schejbal, Martin January 2011 (has links)
This work statistically analyses hypotheses about the presence of antisocial punishment in study of economic experiments. Analysed data source is author's own ABM simulation of antisocial punishment environment. Tested hypotheses and ABM simulations are evolutionary oriented. This represents natural selection of evolving agents (and their groups) interacting with one another. Work is divided by two independent parts of presumptions. Crucial hypothesis of the first part is evolutional advantage from retaliatory punishment, the second part tests hypotheses of evolutional benefits resulting from group selection. Findings of the analysis allow us to accept these crucial hypothesis, and it may be concluded, that antisocial punishment can be regard as an evolutionary advantage, which directly advantages individuals, as well as whole groups.
707

Trigger and reconstruction farms in the HERA-B experiment and algorithms for a Third Level Trigger

Schwanke, Ullrich 30 October 2000 (has links)
Das HERA-$B$-Experiment am Deutschen Elektronen-Synchrotron (DESY) in Hamburg dient der Untersuchung der Physik von Teilchen, die $b$-Quarks enthalten. Der Schwerpunkt des Ex\-pe\-ri\-mentes liegt auf der Messung der CP-Verletzung im System der neutralen $B$-Mesonen. Es wird erwartet, dass die pr\"azise Bestimmung der CP-Asymmetrie im Zerfallskanal $B^0(\bar{B}^0)\to J/\psi K_S^0$ gro{\ss}en Einfluss auf die Weiterentwicklung des Standardmodells der Elementarteilchenphysik und g\"angiger kosmologischer Theorien haben wird. Das HERA-$B$-Experiment nutzt den Protonenstrahl des HERA-Ringes, um in Kollisionen mit einem feststehenden Target paarweise $B$-Hadronen zu erzeugen. Die Wechselwirkungen werden in einem Vorw\"artsspektrometer mit etwa 600.000 Auslesekan\"alen nachgewiesen. Aufgrund der relativ niedrigen Schwerpunktsenergie von 41.6\,GeV sind Ereignisse mit $b$-Quarks im Vergleich zu Wechselwirkungen mit leichteren Quarks um etwa sechs Gr\"o{\ss}enordnungen unterdr\"uckt. Die Selektion von Signalereignissen stellt daher eine besondere Herausforderung dar. Sie wird von einem vierstufigen Datennahme- und Triggerystem \"ubernommen, das die Ereignisrate von 10\,MHz auf etwa 20\,Hz reduziert. Neben speziell entwickelter Elektronik werden im Triggersystem mehrere hundert handels\"ubliche PCs eingesetzt. Die Computer sind in zwei so genannten PC-Farmen mit jeweils mehr als 200 Prozessoren angeordnet, die die Rechenkapazit\"at f\"ur Triggerentscheidungen und die prompte Analyse der Ereignisdaten zur Verf\"ugung stellen. Auf der einen Farm laufen schnelle Triggerprogramme mit einer Rechenzeit von etwa 1--100\,ms pro Ereignis ab. Die andere Farm rekonstruiert die Ereignisse online, bevor die Daten auf Band dauerhaft archiviert werden. Die pro Ereignis aufgewandte Rechenzeit liegt dabei im Bereich einiger Sekunden. Die vorliegende Arbeit behandelt zwei Themenkreise. Einerseits wird die technische Umsetzung der Trigger- und der Rekonstruktionsfarm beschrieben. Besonderes Augenmerk liegt dabei auf den Software-Systemen, die den Farmen erforderliche Kalibrationsdaten verf\"ugbar machen und die zentrale \"Uberwachung der Ergebnisse der ablaufenden Programme gestatten. Der Hauptteil der Arbeit besch\"aftigt sich mit Algorithmen f\"ur eine dritte Triggerstufe, die zus\"atzlich zu existierenden Programmen auf der Triggerfarm zum Einsatz kommen sollen. Der Zerfall $B^0(\bar{B}^0)\to J/\psi X$ hat eine sehr klare Signatur, wenn das $J/\psi$ in ein $e^+e^-$- oder $\mu^+\mu^-$-Paar zerf\"allt. Im Triggersystem wird nach einem Paar entgegengesetzt geladener Leptonen des gleichen Typs gesucht, deren invariante Masse der des $J/\psi$ entspricht und deren Spuren von einem gemeinsamen Vertex in der N\"ahe des Targets ausgehen. Es wird davon ausgegangen, dass die Ausnutzung aller kinematischen Zwangsbedingungen ausreicht, um diesen Zerfallskanal klar von Untergrundereignissen zu trennen. Die dritte Triggerstufe soll dagegen auf Signalprozesse mit weniger kinematischen Beschr\"ankungen angewandt werden. Solche Ereignisse entstehen zum Beispiel dann, wenn zwei in der Proton-Target-Kollision erzeugte $B$-Mesonen semileptonisch zerfallen. Das Triggersystem selektiert lediglich die beiden Leptonen, die aber hier nicht von einem gemeinsamen Vertex kommen. Die dritte Triggerstufe soll f\"ur derartige Zerfallstopologien innerhalb von 100\,ms pro Ereignis weitere Kriterien zur Unterscheidung von Signal- und Untergrundprozessen aus den Daten extrahieren. In der Arbeit wird anhand von Monte-Carlo-Studien untersucht, inwieweit die Daten des Silizium-Vertexdetektors des Experimentes zur Entscheidungsfindung einer dritten Triggerstufe beitragen k\"onnen. Dabei wird die Rekonstruktion von Spuren aus der Zerfallskaskade der $B$-Hadronen zus\"atzlich zu den von der vorhergehenden Triggerstufe selektierten Lep\-ton\-en an\-ge\-strebt. Mithilfe einer schnellen Mustererkennung f\"ur den Vertexdetektor wird gezeigt, dass das Auffinden aller Spuren und die Anwendung von Triggeralgorithmen innerhalb des vorgegebenen Zeitfensters von 100\,ms m\"oglich sind. Die Bestimmung der Spurparameter nahe der Targetregion macht von der Methode des Kalman-Filters Gebrauch, um der Vielfachstreuung im Detektormaterial Rechnung zu tragen. Dabei tritt das Problem auf, dass weder der Impuls der gefundenen Spuren bekannt ist, noch die Materialverteilung im Vertexdetektor aus Zeitgr\"unden in aller Strenge ber\"ucksichtigt werden kann. Durch geeignete N\"aherungen gelingt es, eine ausreichende Genauigkeit f\"ur die Spurparameter zu erreichen. Die aufgefundenen Teilchen bilden den Ausgangspunkt f\"ur Triggeralgorithmen. Hierbei wird untersucht, welche Methoden am besten geeignet sind, um Signal- und Unter\-grund\-ereignisse voneinander zu trennen. Es erweist sich, dass das Auffinden von Spuren mit gro{\ss}em Impaktparameter aussichtsreichere Ans\"atze als eine Suche nach Sekund\"arvertices bietet. / The HERA-$B$ experiment at Deutsches Elektronen-Synchrotron (DESY) Hamburg aims at investigating the physics of particles containing $b$ quarks. The experiment focusses on measuring CP violation in the system of neutral $B$ mesons. It is expected that the precise determination of the CP asymmetry in the channel $B^0(\bar{B}^0)\to J/\psi K_S^0$ will have an impact on the further development of the Standard Model of Elementary Particle Physics and cosmological theories. The HERA-$B$ experiment uses the proton beam of the HERA storage ring in fixed-target mode. $B$ hadrons are produced in pairs when protons from the beam halo interact with target nuclei. The interactions are recorded by a forward-spectrometer with roughly 600.000 readout channels. At the HERA-$B$ centre-of-mass energy of 42.6\,GeV, the $b\bar{b}$ cross section is only a tiny fraction of the total inelastic cross section. Only one in about 10$^6$ events contains $b$ quarks, which turns the selection of signal events into a particular challenge. The selection is accomplished by a four-stage data acquisition and trigger system reducing the event rate from 10\,MHz to about 20\,Hz. Besides custom-made electronics, several hundreds of PCs are used in the trigger system. The computers are arranged in two so-called PC farms with more than 200 processors each. The PC farms provide the computing capacity for trigger decisions and the prompt analysis of event data. One farm executes fast trigger programs with a computing time of 1--100\,ms per event. The other farm performs online reconstruction of the events before data are archived on tape. The computing time per event is in the range of several seconds. This thesis covers two topics. In the beginning, the technical implementation of the trigger and the reconstruction farm are described. In doing so, emphasis is put on the software systems which make calibration data available to the farms and which provide a centralised view on the results of the executing processes. The principal part of this thesis deals with algorithms for a Third Level Trigger. This trigger is to come into operation on the trigger farm together with existing programs. Processes of the type $B^0(\bar{B}^0)\to J/\psi X$ have a very clean signature when the $J/\psi$ decays to a $e^+e^-$ or $\mu^+\mu^-$ pair. The trigger system attempts to identify two unlike-sign leptons of the same flavour whose invariant mass matches the $J/\psi$. In later steps, the tracks are required to originate from a common vertex close to the target. It is assumed that these kinematic constraints are sufficient to pick out events of this type among the copious background processes. In contrast, the Third Level Trigger is to be applied to signal processes with fewer kinematic constraints. Such events occur for example when two $B$ mesons, which were created in a proton-target collision, decay semileptonically. The trigger system selects merely the two leptons which do not originate from a common vertex in this case. The Third Level Trigger has 100\,ms at its disposal to extract further criteria from the data which can serve to distinguish between signal and background events. This thesis investigates with the aid of Monte-Carlo simulations how the data of the experiment's silicon vertex detector can contribute to the decisions of a Third Level Trigger. The trigger aims at reconstructing tracks from the decay cascade of $B$ mesons in addition to the leptons selected by the preceding trigger levels. A fast pattern recognition for the vertex detector demonstrates that the reconstruction of all tracks and the application of trigger algorithms are possible within the given time slot of 100\,ms. The determination of track parameters in the target region exploits the Kalman-filter method to account for the multiple scattering of particles in the detector material. The application of this method is, however, made difficult by two facts. First, the momentum of the reconstructed tracks is not known. And, second, the material distribution in the detector cannot be taken into consideration in detail due to timing limitations. Adequate approximations for the momentum and the material traversed by a particle help to accomplish a sufficient accuracy of the track parameters. The reconstructed tracks constitute the starting point of several trigger algorithms, whose suitability to select signal events is investigated. Our studies indicate that the reconstruction of tracks with large impact parameters is a more promising approach than a search for secondary vertices.
708

Alltagsintuitionen zur Willensfreiheit

Deutschländer, Robert 27 June 2018 (has links)
Die Willensfreiheit ist ein zentraler Bestandteil des alltäglichen menschlichen Denkens und bildet eine wichtige Grundlage für Mechanismen unserer Gesellschaft. Trotz dieser zentralen Stellung herrscht unter Philosophen und Psychologen Uneinigkeit darüber, was Willensfreiheit eigentlich bedeutet. Dies wird besonders bei Experimenten zur Untersuchung der Willensfreiheit wie das Libet-Experiment deutlich. In dieser Arbeit wird in drei Surveys empirisch untersucht, ob der Freiheitsbegriff, mit dem die Libet-Experimente operieren, von den Freiheitsintuitionen der Laien gestützt wird, oder ob Laien eher den konträren Freiheitsintuitionen der Philosophen zuneigen. Die Ergebnisse der vorgestellten Untersuchungen zeigen, dass Laien eine von den philosophischen Vorstellungen abweichende Vorstellung von Freiheit haben. / Free will is one of the most crucial concepts in our daily life. It represents one of the most important aspects of daily human behaviour and has crucial importance in societal mechanism. However, despite its importance and long tradition philosophers still disagree on a definition. At the heart of the problem lie diverging intuitions about what is important for the concept of freedom. This is particular obvious in neuroscientific experiment, like the famous Libet-Experiment. Here I investigate in three empirical surveys whether the lay intuitions about freedom match freedom intuitions on which the Libet-experiment are based or rather the classical philosophical intuitions about freedom. For this purpose I adopt the empirical approach of experimental philosophy. The results demonstrate that lay people’s intuitions are pretty much in line with assumption that are made by the Libet-Experiment and contradict common philosophical intuitions about free will.
709

Ensino de isometrias na educação básica: uma aplicação didática em sala de aula / Teaching isometrics in basic education: a didactic application in the classroom

Cona, Debora Costa 18 May 2017 (has links)
Nesta dissertação apresentamos uma sequência de atividades não tradicionais, com foco no ensino e na aprendizagem de Geometria, em particular no que se refere às Isometrias no Plano, elaboradas para alunos de Ensino Fundamental, e o resultado de sua aplicação a oito turmas de 9o ano, como forma de desenvolver habilidades de raciocínio desses alunos. Utilizamos para esse experimento o Design Experiment, experimento de ensino fundamentado no aprimoramento contínuo, e a teoria de Van Hiele baseada na tese de doutorado de Adela Jaime-Pastor (1993), com uma série de atividades elaboradas e aplicadas pela professora/pesquisadora envolvendo as translações e as reflexões, através das fases de aprendizagem e níveis de raciocínio que os alunos desenvolvem com a aplicação dessa teoria. Esse experimento foi dividido em dois momentos, aplicação com quatro turmas de 9o ano em 2015 e aplicação com outras quatro turmas de 9o ano em 2016, subdivididos em outras duas situações, atividades sobre translações e atividades sobre reflexões. Os dados desse experimento foram obtidos através das produções dos alunos, que trabalharam em duplas, em sala de aula, registrados por meio de fotos, vídeos e áudios gravados pela própria pesquisadora. Também utilizamos as bonecas de papel de Brigitte Servatius (1997), com as quais foram trabalhadas translações e reflexões. Os alunos participantes do experimento finalizaram-no com noções sólidas das características das isometrias e um visível progresso em seu nível de conhecimento. A forma como as atividades foram realizadas trouxeram reflexos na rotina desses estudantes em sala de aula, tornando evidente que a busca por situações que despertem o interesse dos alunos de forma inovadora pode gerar melhores resultados e a motivação de uma contínua aprendizagem. / In this dissertation we present a sequence of non-traditional activities, focusing on the teaching and learning of Geometry, in particular regarding the Isometrics in the Plan, elaborated for elementary school students, and the result of its application to eight classes of 9th grade , As a way to develop students\' reasoning skills. We used for this experiment the Design Experiment, a teaching experiment based on continuous improvement, and Van Hiele\'s theory based on Adela Jaime-Pastor\'s (1993) doctoral thesis, with a series of activities elaborated and applied by the teacher/researcher involving the translations and the reflections, through the phases of learning and levels of reasoning that the students develop with the application of this theory. This experiment was divided in two moments, application with four classes of 9th grade in 2015 and application with four other groups of 9th grade in 2016, subdivided into two other situations, activities on translations and activities on reflections. The data of this experiment were obtained through the productions of the students, who worked in doubles, in the classroom, recorded through photos, videos and audios recorded by the researcher herself. We also used the paper dolls of Brigitte Servatius (1997), with which we worked on translations and reflections. The students participating in the experiment finalized it with solid notions of the characteristics of the isometries and a visible progress in their level of knowledge. The way the activities were carried out brought reflexes to the routine of these students in the classroom, making it evident that the search for situations that arouse the students\' interest in an innovative way can generate better results and the motivation of continuous learning.
710

Dynamika spinové polarizace v polovodičích / Dynamics of spin polarization in semiconductors

Janda, Tomáš January 2012 (has links)
In this work we study ultrafast laser-induced magnetization dynamics in samples of ferromagnetic semiconductor Ga1−xMnxAs with a nominal concentration of Mn within the range of x = 0,015-0,14. To get information about magnetization movement we use magneto-optic phenomena PKE and MLD in a time-resolved pump & probe experiment. Thorough analysis of the measured magneto-optical signal allows us to disentangle contributions due to angular movement of magnetization and due to demagnetization and to reconstruct 3D motion of magnetization vector without any numerical modeling. First we explain the basis of this experimental method and we demonstrate its utilization on the measured data. After that we study angular movement of magnetization vector and its dependence on the external magnetic field, excitation intensity and Mn concentration. The pump pulse helicity dependent and independent dynamics were treated separately. In the case of demagnetization we have been able to observe not only its intensity and Mn doping dependence but also the magnetic field dependence, which has not been reported so far in the literature.

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