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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.
51

Simulátor signálu částečného výboje v pásmu ultrakrátkých vln / Simulator of partial discharge signal in the UHF band

Škoda, Martin January 2019 (has links)
This master thesis deals with the problem of the origin and expression of partial discharges in dielectric materials. In the thesis the theoretical foundations, types and parameters of partial discharges are described. In particular, it deals with UHF (ultra high freqeuncy) electromagnetic radiation using UHF method of partial discharge detection. It also deals with the partial discharge UHF signal simulation. The development of UHF sensor systems for partial discharges requires a dive that can simulate them as accurately as possible. Furthermore, a workplace was designed for simulation and detection of partial discharges and processing of their time and frequency characteristics.
52

Den multifunktionella byggnadens roll i ett socialt hållbart kvarter / The role of the multifunctional building in a socially sustainable neighbourhood

Olsson, Andreas, Spetz, Kajsa January 2020 (has links)
Denna studie handlar primärt om social hållbarhet som är ett stort och omfattande begrepp. I dagens stadsplanering används begreppet i ett bredare perspektiv. Studien har som syfte att fokusera mer ingripande på social hållbarhet för enskilda multifunktionella byggnader, genom att samla in kunskap om ämnet och belysa innebörden. De valda multifunktionella byggnaderna är Icon i Växjö och Spektrum i Göteborg. Syftet med denna studie är att genom forskning och utvärdering konkretisera människans dagliga behov och hur de kan tillgodoses i en multifunktionell byggnad samt dess bidragande roll för ett socialt hållbart kvarter. Målet är att få en tydligare uppfattning om vilken påverkan den multifunktionella byggnaden har på ett kvarter. Genom utformning och tillämpning av ett verktyg som tagits fram inom ramen för den aktuella studien skall byggnadens sociala hållbarhet kunna utvärderas utifrån människans vardagliga liv, behov och intressen.  Intervjuer med ansvariga projektledare, arkitekter, handledare och sakkunniga har tillsammans med insamling av vetenskapliga rapporter, studiebesök, enkät och observationer varit centrala tillvägagångssätt för studien. Att arbeta mot en mer blandad bebyggelsemiljö och byggnader som har olika verksamheter som samsas är idag alltmer förekommande för att uppnå ett livligare och trevligare stadsrum. Utifrån studiens utformade verktyg har respektive multifunktionell byggnad fått olika sociala poäng som baseras på storlek, verksamheter, tillgänglighet och multifunktionalitet. Studien visar att respektive multifunktionell byggnad har givit mervärde till sitt område. / This study focuses primarily on social sustainability, which is a large and comprehensive concept. In today's urban planning, social sustainability is used on a broader perspective. The study aims to focus more on the concept for individual multifunctional buildings by gathering knowledge about the subject and highlight the meaning. The chosen multifunctional buildings are Icon in Växjö and Spektrum in Gothenburg. The purpose of this study is, through research and evaluation, to concretize people's daily needs and how they can be met in a multifunctional building and its contribution to a socially sustainable neighbourhood. The goal is to get a better understanding of which impact the multifunctional building has on its block. The goal is also designing and application of a tool developed in the context of the current study and to use this tool to evaluate the building's social sustainability based on people's everyday lives, needs and interests. Interviews with responsible project managers, architects, supervisors and other experts, together with the gathering of scientific reports, study visits, questionnaires and observations, has been the studies central approach. Working towards a more mixed urban environment and buildings that have different operation that are combined is nowadays increasingly common for a livelier and more enjoyable urban space. Based on the study´s designed tool, each multifunctional building has received different social points that depends on size, operations, availability and multifunctionality. The study shows that each multifunctional building has added value to its area.
53

Spektrální vlastnosti zdrojového signálu jako údaje o identitě mluvčího / Spectral properties of the source signal as speaker-specific cues

Vaňková, Jitka January 2012 (has links)
Despite a continuous development in computer sciences and related disciplines, speaker identification remains one of the most challenging tasks in forensic phonetics. The reason for this is the fact that our knowledge of how identity is reflected in the acoustic signal is still limited. The present study aims to contribute to the search of speaker-specific cues by examining spectral properties of the source signal. Specifically, it examines to what extent three short-term measures of spectral tilt, namely H1-H2, H1-A1 and H1-A3, can discriminate 16 Czech female speakers. It also addresses the influence of vowel quality, syllable status with respect to stress and position of stress group in the utterance on the values of these measures. The results show that these parameters do have some discriminative power, though the contribution of individual parameters differs. The study indicates that discrimination of speakers is the most successful in stressed syllables and argues that individual vowels could differ in their usefulness for speaker identification. The results of LDA based on these short- term measures of spectral tilt were complemented with long-term measures, namely alpha index, Kitzing index and Hammarberg index which quantify the slope of the LTAS. The present study suggests that...
54

Mimoškolní aktivity dětí a mládeže s poruchami autistického spektra / Extracurricular activities for children and youth with autism spectrum disorders

Novotná, Michaela January 2013 (has links)
Diplomová práce seznamuje s jednotlivými symptomy a typy pervazivních vývojových poruch. Předkládá možnosti využití široké škály různých přístupů či programů při práci s těmito žáky. Věnuje se hře ve spojení s poruchami autistického spektra a s využitím volného času v rámci školy, rodiny či projektu. Práce nastiňuje jednotlivá úskalí mimoškolních aktivit dětí a mládeže s poruchami autistického spektra. Zdůrazňuje, jakou významnou pozici mimoškolní aktivity v životě dětí a mládeže zastupují a jak důležité jsou pro všestranný rozvoj. Dále mapuje volnočasové aktivity, kterým se věnují děti a mládež s poruchami autistického spektra v rámci rodiny, školy a nejrůznějších projektů. Nedílnou součástí mimoškolních činností se stává hra, kterou lze využít jako jednu z možných forem práce s dětmi a mládeží s poruchami autistického spektra. Volný čas a hra se také prolíná návrhem projektu, který je součástí diplomové práce. Projekt nese název: "Společná škola v přírodě".
55

Characterizing cosmic neutrino sources

Mohrmann, Lars 30 November 2015 (has links)
Das IceCube Neutrino Observatorium ist ein km^3-großes Neutrinoteleskop und befindet sich am geographischen Südpol. Das Ziel des Experiments ist es, kosmische Neutrinos nachzuweisen. Es wird erwartet, dass solche Neutrinos in Wechselwirkungen von hochenergetischer kosmischer Strahlung mit Materie oder Photonen in der Nähe ihrer Beschleunigungsumgebung entstehen. Der erste Nachweis für einen Fluss von kosmischen Neutrinos wurde von der IceCube-Kollaboration erbracht. Der Ursprung des Flusses ist noch nicht bekannt, dennoch können die Eigenschaften der Quellen durch eine Messung des Energiespektrums und der Zusammensetzung aus Elektron-, Muon-, und Tau-Neutrinos des Flusses eingeschränkt werden. Die vorliegende Arbeit stellt die erste umfassende Analyse von Daten des IceCube-Experiments im Hinblick auf diese Eigenschaften des Flusses dar. Hierfür wurden mehrere Datensätze kombiniert und gemeinsam analysiert. Es wurden experimentell beobachtete Verteilungen von rekonstruierter Energie, Zenithwinkel und Teilchen-Signatur mit Modellverteilungen angepasst. Unter der Annahme, dass der Fluss isotrop ist und zu gleichen Teilen aus allen Neutrino-Flavors besteht, wird das Spektrum durch ein Potenzgesetz mit Normalisierung (6.7_{-1.2}^{+1.1})x10^{-18}GeV^{-1}s^{-1}sr^{-1}cm^{-2} bei 100 TeV und spektralem Index -2.50+-0.09 zwischen Neutrino-Energien von 25 TeV und 2.8 PeV gut beschrieben. Ein spektraler Index von -2 kann mit einer Signifikanz von 3.8 Standardabweichungen ausgeschlossen werden. Die Flavor-Zusammensetzung ist kompatibel mit Erwartungen für Standard-Prozesse der Neutrino-Produktion. Die ausschließliche Produktion von Elektron-Neutrinos kann hingegen mit einer Signifikanz von 3.6 Standardabweichungen ausgeschlossen werden. Unter der Annahme, dass die Neutrino-Flavor während der Propagation von den Quellen zur Erde durch Standard-Neutrino-Oszillationen transformiert werden, beträgt der gemessene Anteil an Elektron-Neutrinos an der Erde (18+-11)%. / The IceCube Neutrino Observatory is a km^3-sized neutrino telescope located at the geographical South Pole. Its primary purpose is the detection of high-energy cosmic neutrinos. Such neutrinos are expected to be produced in interactions of high-energy cosmic rays with ambient matter or photons close to their acceleration sites. The IceCube Collaboration has reported the first evidence for a flux of high-energy cosmic neutrinos. While the origin of the flux remains unknown so far, the properties of its sources can be constrained by measuring its energy spectrum and its composition of electron, muon, and tau neutrinos. The present work constitutes the first comprehensive analysis of IceCube data with respect to these principal characteristics of the flux. Several data sets were assembled and simultaneously studied in a combined analysis. Experimentally observed distributions of reconstructed energy, zenith angle and particle signature were fitted with model distributions. Assuming the cosmic neutrino flux to be isotropic and to consist of equal flavors at Earth, the all-flavor spectrum is well described by a power law with normalization (6.7_{-1.2}^{+1.1})x10^{-18}GeV^{-1}s^{-1}sr^{-1}cm^{-2} at 100 TeV and spectral index -2.50+-0.09 for neutrino energies between 25 TeV and 2.8 PeV. A spectral index of -2 is disfavored with a significance of 3.8 standard deviations. The flavor composition is compatible with that expected for standard neutrino production processes at the sources. However, a scenario in which only electron neutrinos are produced is disfavored with a significance of 3.6 standard deviations. Assuming that standard neutrino oscillations transform the neutrino flavors during propagation from the sources to the Earth, the measured fraction of electron neutrinos at Earth is (18+-11)%.
56

Das absolutstetige Spektrum eines Matrixoperators und eines diskreten kanonischen Systems

Fischer, Andreas. Unknown Date (has links) (PDF)
Universiẗat, Diss., 2004--Osnabrück.
57

The endocannabinoid system and autistic behavior in the Fmr1- KO mouse

Lenz, Frederike 22 January 2018 (has links) (PDF)
Background: Background of this work was the investigation of the endocannabinoid system (ECS) in the Fmr1 knock- out (KO) mouse. The Fmr1- KO mouse is a mouse model for fragile X syndrome (FXS). FXS is the leading monogenic cause for autism spectrum disorders (ASD) in humans. The Fmr1- KO mouse displays autistic behavior such as an impaired social interaction, repetitive behavior, cognitive deficits, increased anxiety and aggressiveness. Alterations of the ECS have been suggested to play a key role in the etiopathology of a variety of neuropsychiatric disorders. Until today, little has been described about the involvement of the ECS in ASD. Interrogation: 1. Evaluating the manifestation of typical cannabinoid- induced effects in the Fmr1- KO mouse 2. Investigating the influenceability of autistic symptoms with THC treatment in the Fmr1- KO mouse 3. Analyzing the signaling cascade of the stimulated and unstimulated ECS in different brain regions of the Fmr1- KO mouse Material and Methods: Experiments were carried out on adult (12±1 weeks old) male Fmr1- KO and Fmr1- wild- type (WT) mice from the C57BL/6J- (B6)- background. N= 15 mice received THC (10mg/kg bodyweight) and N= 16 received WIN55,212 (3mg/kg bodyweight). 30min after injection, the body temperature was measured and the distance animals moved in an open field during 15min was recorded (locomotion). Then, animals were placed with their forepaws onto a horizontally fixed bar and the time remaining in this position (catalepsy) was measured. Finally animals were placed on a preheated plate and the temperature at which a pain stimulus occurred was determined (testing analgesia). All 4 experiments are called tetrad experiment. Afterwards changes in body temperature, locomotion, catalepsy and analgesia of the animals was evaluated. To explore long-term effects of THC after the tetrad, N= 15 animals were tested in a social interaction test with a female contact mouse, 10 and 20 days after THC treatment. Therefore, the tested mouse and the contact mouse were placed together into a cage and the time mice spent in social interaction (nose, body and anogential sniffing, allogrooming and body contact) was manually quantified during 6min of recorded testing time. Another group of N= 19 received a premedication of rimonabant (Cannabinoid- receptor 1 (CB1) antagonist, 3mg/kg bodyweight) 30min prior to THC treatment. Rimonabant prevents THC from binding to CB1 and therefore allows the assessment of the involvement of CB1 in mediating social behavior. Furthermore the suggestibility of context-dependent fear conditioning with THC treatment has been tested on N= 13 mice. Animals were placed into a conditioning chamber that delivered 6 short electric shocks with a 30sec pause to their paws (conditioning phase). Immediately afterwards mice received THC or placebo. 24h later contextdependent fear was evaluated by quantification of the time mice spent freezing in the conditioning-chamber (fear) without receiving foot shocks. Intraneuronal signaling of the ECS was analyzed with N= 29 animals using western blots. Quantities of phosphorylated (“activated”) protein kinases (ERK, AKT and S6) from different brain homogenates (hippocampus, striatum, cortex and cerebellum) were therefore measured after THC or placebo injection (30 minutes prior to sacrificing). Results: Cannabinoids induced hypothermia, hypolocomotion, analgesia and catalepsy in WTmice. These effects were significantly less detectable in Fmr1- KO mice. Effects of both cannabinoids, THC and WIN55,212, were comparable with a slightly greater but not significant efficiency of THC. THC treated WT- mice exhibited further reduced social interaction 10 days after treatment, an effect that was partially prevented by premedication with rimonabant. THC increased social interaction in Fmr1- KO mice comparable to the level of untreated WT- mice. THC had no effect on behavior of WT- mice in context-dependent fear conditioning. Fmr1- KO mice showed significant less contextdependent fear conditioning compared to WT- mice. THC facilitated the recognition of an anxiety-correlated context in Fmr1- KO mice comparable to untreated WT- mice. In western blots significant changes in the THC- induced signaling cascade were detectable and depending on genotype, brain-region and analyzed protein-kinase. In the hippocampus there were no changes in untreated Fmr1- KO mice compared to WT- mice. THC had no effect on activation of protein-kinases in WT- and Fmr1- KO mice. In the striatum there were no changes in untreated Fmr1- KO mice compared to WTmice. THC significantly increased activity of ERK, AKT and S6 in WT-mice and not in Fmr1- KO mice. In the cortex of untreated Fmr1- KO mice AKT showed a significantly increased activity compared to WT- mice. THC significantly increased AKT activity in WT- mice without having an effect on KO- mice. In the cerebellum there were no changes in untreated Fmr1- KO mice compared to WT- mice. THC significantly increased ERK- activity in Fmr1- KO mice but had no effect on protein kinase activity in WT- mice. Conclusion: We observed physiological cannabinoid effects in WT- mice after treatment with THC and WIN55,212. These effects are significantly attenuated in Fmr1- KO mice. This may be interpreted as a desensitization of the ECS in the Fmr1- KO mouse. At the same time it was demonstrated that THC has the potential to improve context dependent memory consolidation and to increase social interaction in the Fmr1- KO mouse. In particular the influence of THC on impaired social interaction should be a target of further investigations to find possible therapeutic options for this typical symptom of Autism. Underlying molecular mechanisms remain unclear and the analysis of THC stimulated intraneuronal signaling gave no clear indication of possible molecular alterations in the Fmr1- KO mouse.
58

Aplikace kombinatorických aukcí na veřejné zakázky / Application of Combinatorial Auctions on Public Procurement

Kohoutová, Adéla January 2014 (has links)
The public procurement draws a lot of attention in terms of treatment with public resources. Unfortunately this attention has mostly negative character. The aim of this Diploma Thesis is to bring an untraditional overview on the processing of public procurement and introduce one of the modern ways of using auction mechanisms. Combinatorial auctions can, as it already happened in other areas, open new possibilities for contracting authorities and bidders who participate in procurement conducted in accordance with Czech legislation. Also this Diploma Thesis can be the inspiration for thought if the current rules for public procurement are in accordance with the best interests of contracting authorities and bidders. In order to present the application of combinatorial auctions on public procurement the mathematical model based on partially real data was compiled in software Lingo. The results of such model were used as the source for the effectiveness analysis of discussed topic.
59

Automatické vyhodnocení signálů s využitím Fourierovy transformace / Automatic signal evaluation using Fourier transform

Rudžík, Matej January 2020 (has links)
This master’s thesis deals with signal evaluation using Fourier transform. In the theoretical section, different methods of signal analysis with an emphasis on a Fast Fourier Transform are described. Theoretical section also contains description of common machinery faults and their diagnosis using frequency spectrum analysis. In the practical section, an algorithm for signal evaluation with an emphasis on coherence condition was designed in the Matlab environment. This algorithm was later used to evaluate submitted signals.
60

Digitální modelovaní zvuku orchestru / Digital modeling of the orchestra sound

Puczok, Daniel January 2008 (has links)
This report is guide along simulation of sound sources and orchestra. Basic physical characteristics necessary to the simulation of sound sources are described here. Description of the creation of directivity files in ODEON and theirs conversion from CATT-Acoustic to ODEON are described here too. Acquired directivity files were used for simulation of orchestra and for testing the directivity characteristics to room acoustics parameters.

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