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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.
571

Nástroj pre užívateľsky prívetivú tvorbu dotazov nad priestorovými dátami

Kučarová, Žaneta January 2019 (has links)
This thesis describes the design, implementation and user testing of a user friendly spatial data query tool. The user interface was developed in cooperation with Clever Analytics. The company is developing a solution for spatial data visualization on an interactive map and data observation using various metrics. It is used by managers as support for their decisions. Designed tool allows simple creation of new indicators for visualizing metrics. It also allows editing and combining of already existing indicators. Users from management do not need to know technical background of entering metrics or creating indicators, therefore they are not dependent on consultants. It supports faster decision making and guides towards natural data exploration.
572

Hantering av kursmjukvaror vid Linköpings universitet / Management of course software at Linköping University

Udd, Gustaf, Axelsson, Isak, Duvaldt, Jakob, Bergman, Oscar, Måhlén, Joar, Lundin, Oskar, Abrahamsen, Tobias, Sköldehag, Sara January 2020 (has links)
Denna kandidatrapport är skriven av åtta studenter i kursen Kandidatprojekt i mjukvaruutveckling, TDDD96, vid Linköpings universitet under våren 2020. Kandidatrapporten inkluderar en sammanfattning av det arbete som utförts i projektet. Till projektet tillhörde ett uppdrag på beställning av Digitala resursenheten vid Linköpings universitet. Uppdraget var att skapa en webbapplikation där examinatorer och handledare för kurser vid Linköpings universitet på ett enkelt och intuitivt sätt kan beställa mjukvara till sina respektive kurser. Projektgruppen jobbade agilt och byggde projektet i Python samt JavaScript. Applikationen nådde alla mål satta tillsammans mellan kunden och projektgruppen och resulterade i en fungerande produkt som kunde utökas och modifieras enligt kundens behov. Till kandidatrapporten inkluderas även individuella bidrag skrivna av vardera gruppmedlem som djupdykt inom ett specifikt ämne eller område.
573

Design and Implementation of Angular Vibration Testing Equipment

Zhou, Zhuohang, Nilsson, Martin January 2018 (has links)
This thesis is done by two students from Blekinge Institute of Technology as an end of the master of engineering program with emphasis on applied mechanics. The thesis is done in cooperation with Axis Communications AB in Lund which develop surveillance cameras. The task was to design and implement an Angular Vibration Testing Equipment. Axis needs this to test their surveillance cameras for angular vibrations. These vibrations occur usually on cameras located on poles placed at roads and at train stations. The thesis has been carried out in three different phases where the first phase handled a deeper understanding of the problem, planning and investigating of related works. Axis has a solution for smaller cameras called Shakespeare MK I and this was used as an inspiration for us. The second phase included concept generation and concept evaluation. This has been done with brainstorming, workshop and concept scoring. At the last phase a prototype was built and tested and a detailed design was made. Two versions of the prototype were made and they showed that the concept works well. The project resulted in a working prototype that can transform linear motion to rotation around two axes. A drawing and a cost calculation were made for the final concept. The final construction is still not completely optimized and has improvement and adjustment possibilities that might be needed.
574

Evaluating JavaScript Frameworks

Salomaa, Josefin January 2020 (has links)
Web application frameworks have become a common part of software development, with each programming language having its own specific frameworks. However, choosing the right framework can be a daunting task when there are so many frameworks on the market and factors to consider. Previous research has attempted to solve this problem by evaluating frameworks based on several different metrics. While the results offer a way to rank the frameworks, they do not tell us much about the actual process of evaluating a framework, or why certain metrics matter and in what situation. This project aimed to answer these questions by conducting a literature review to gather information about the existing evaluation methods and metrics. Based on these results, an evaluation criteria was developed to provide an overview of when to evaluate what. Furthermore, a user survey was done to measure the usability of three popular JavaScript frameworks. Lastly, a controlled experiment was conducted to test the performance of the three frameworks. The results show that different frameworks have different strengths and weaknesses as they received different scores from the methods. Moreover, the results show that when choosing a framework, one has to consider which factors matter most as it may not always be possible to find a framework that has it all.
575

Etudes à haute résolution angulaire de la cinématique des enveloppes proto-stellaires / High angular resolution studies of the kinematics of proto-stellar envelopes

Gaudel, Mathilde 27 November 2018 (has links)
Les étoiles se forment par effondrement gravitationnel de condensations pré-stellaires. Le jeune embryon stellaire (phase Classe 0) croît en masse par l'accrétion progressive de l'enveloppe de gaz et de poussières dans lequel il est enfoui. Par conservation du moment cinétique, si le moment du coeur pré-stellaire est totalement transféré à l'embryon pendant la phase d'accrétion, la force gravitationnelle ne peut contrer la force centrifuge et l'embryon se fragmente prématurément. Pour former une étoile comme notre Soleil, l'enveloppe en rotation doit nécessairement réduire son moment cinétique de 5 à 10 ordres de grandeur en l'évacuant ou en le redistribuant. L'un des principaux défis de la formation stellaire est de quantifier l'ampleur de ce "problème du moment cinétique" et d'identifier les mécanismes responsables de la redistribution du moment.L'objectif de cette thèse est d'étudier la cinématique des enveloppes proto-stellaires de Classe 0 afin d'établir leurs distributions de moment cinétique. Pour cela, j'ai utilisé des observations de raies moléculaires à haute résolution angulaire de l'Interféromètre du Plateau de Bure et du télescope de 30m de l'IRAM issues du large programme CALYPSO (Continuum and Lines in Young Protostellar Objects, PI : Ph. André) pour un échantillon de 12 proto-étoiles de Classe 0 à une distance d<400 pc. Cette analyse a permis de mesurer des mouvements de rotation différentielle et d'établir, pour la première fois, des distributions radiales du moment cinétique spécifique sur une grande gamme d'échelles (~50-10000 au) dans 11 des 12 enveloppes proto-stellaires de l'échantillon. Deux régimes distincts ont ainsi été mis en exergue: un profil constant à petites échelles (<1600 au) et une augmentation du moment avec le rayon aux grandes échelles (1600-10000 au).Le profil constant montre que la matière participant directement à la formation de l'étoile possède un moment cinétique spécifique (~5 10^-4 km/s pc, <1600 au) similaire à celui observé dans les petits disques entourant les étoiles T-Tauri.Les gradients de vitesse observés aux grandes échelles (>3000 au), historiquement utilisés pour mesurer la rotation des coeurs et quantifier le problème du moment cinétique, ne sont pas dus à la pure rotation des enveloppe proto-stellaires, mais sont dominés par d'autres mécanismes. Plusieurs scénarios sont donc discutés pour interpréter le changement de régime dans les profils de moment cinétique aux échelles >1600 au: une empreinte des conditions initiales de la phase pré-stellaire, un changement de mécanismes dominants (contre-rotation, transition effondrement-rotation) ou l'influence de la dynamique des filaments interstellaires (turbulence, effondrement, chocs) dans lesquels les proto-étoiles sont enfouies. / Stars form via the gravitational collapse of a pre-stellar condensation. The young stellar embryo (Class 0 phase) mass increases via the progressive accretion of the gaseous and dusty envelope within which it is buried. As a direct consequence of the angular momentum conservation, if the angular momentum of the pre-stellar core is totally transferred to the central embryo during the accretion phase, the gravitational force can not counteract the centrifugal force and the embryo fragments prematurely before reaching the main sequence. To form a star such as our Sun, the rotating envelope needs to reduce its angular momentum by 5 to 10 orders of magnitude by ejecting or redistributing it. One of the main challenges of stellar formation is to quantify the amplitude of this "angular momentum problem" and identify the mechanisms responsible for the angular momentum redistribution.The goal of this PhD thesis is to study the kinematics of Class 0 protostellar envelopes in order to probe the distribution of their angular momentum. To do this, I used high-resolution observations of molecular lines with the Plateau de Bure Interferometer and the 30m telescope at IRAM taken as part of the large programme CALYPSO (Continuum and Lines in Young Protostellar Objects, PI : Ph. André). The sample gathers 12 Class 0 protostars with distances d<400 pc. This analysis allows to measure differential rotation motions and provides, for the first time in a large sample, robust constraints on the radial distributions of specific angular momentum in a large range of scales (~50-10000 au) for 11 of the 12 protostellar envelopes targeted in the sample. Two distinct regimes are revealed: a constant profile at small scales (<1600 au) and an increasing of the angular momentum at larger radii (1600-10000 au).The constant profile shows that the specific angular momentum (~5 10-4 km/s pc, <1600 au) of the material directly involved in the star formation is similar to the value observed in the small disks surrounding the T-Tauri stars.Velocity gradients observed on large scales (>3000 au) - that are historically used to measure the rotation of the core and quantify the angular momentum problem - are not due to pure envelope rotation but can be dominated by other mechanisms. I discuss several scenarios in order to interpret this change of regime in the angular momentum profiles at scales >1600 au: the imprints of the initial conditions of the pre-stellar phase, a change of dominant mechanisms (counter-rotation, transition between infall and rotation) or the influence of the interstellar filament dynamics (turbulence, collapse, shocks) within which protostars are buried.
576

Angular Analysis of a Wide-Band Energy Harvester based on Mutually Perpendicular Vibrating Piezoelectric Beams

Mirzaabedini, Sohrab 12 1900 (has links)
The recent advancements in electronics and the advents of small scaled instruments has increased the attachment of life and functionality of devices to electrical power sources but at the same time granted the engineers and companies the ability to use smaller sources of power and batteries. Therefore, many scientists have tried to come up with new solutions for a power alternatives. Piezoelectric is a promising material which can readily produce continuous electric power from mechanical inputs. However, their power output is dependent upon several factors such as, system natural frequency, their position in the system, the direction of vibration and many other internal and external factors. In this research the working bandwidth of the system is increased through utilizing of two different piezoelectric beam in different directions. The dependency of output power with respect to rotation angle and also the frequency shift due to the rotation angle is studied.
577

Spatiotemporal Manipulation of Optical Vortices

Zang, Yimin January 2021 (has links)
No description available.
578

Derivation of the angular momentum of primary fission fragments from isomeric yield ratio by TALYS using Python

Bagher Nori, Mohammad January 2021 (has links)
The general fission process is well known and is applied in nuclear power plants all over the world. However many properties of fission fragments are still not well understood. The angular momentum distribution of fission fragments is an important property to gain a better understanding of the fission process, and that can be derived indirectly from isomeric yield ratios. The goal of this project has been to develop a script in Python that runs the nuclear reaction code TALYS with the Total Monte Carlo method to calculate the isomeric yield ratio. The script generates a matrix consisting of excitation energies and angular momenta that is provided to TALYS. One matrix corresponds to one calculation of the isomeric ratio. Thus, the dependency of the isomeric yield ratio on these matrices can be observed. After looking into the matrices, the dependencies of the isomeric yield ratios on the excitation energies and the angular momentum distribution are observed. In this project, the calculated isomeric yield ratios are compared with the experimental value obtained from an experiment conducted in August of 2019 at the IGISOL-JYFLTRAP facility in Jyväskylä, Finland. It is worth mentioning that, fission system is of Uranium-238 which was induced by a proton beam at an energy of 25 MeV. The dependency of the isomeric yield ratio (IYR) on the angular momentum and the excitation energy has been investigated. However, it has proved more difficult than expected, to deduce an estimation for the angular momentum distribution. Another finding of this project is that the two codes used, GEF and TALYS sometimes produce inconstant results.
579

Development of an event generator for antihyperon-hyperon pair production in antiproton-proton collisions

Shen, Vitor Jose January 2022 (has links)
The goal of this project was to develop a lightweight Monte-Carlo (MC) event generator for hyperon pair production in antiproton-proton collisions, and demonstrate it in one of the hyperon decay reaction channels, which is collisions of proton and antiproton to lambda hyperon and anti-lambda hyperon, and they decay to antiproton-positive pion pair, and proton-negative pion pair. The prototype of this external MC event generator we presented here is based on the software framework of ROOT. Compared to the corresponding framework of embedded MC event generators that is currently used in the PANDA experiment at FAIR, PandaRoot, it allows for easier and quicker testing of new models or formalisms on synthetic data, for example for studying spin observables like polarisation. The event generator was benchmarked by studying angular distributions in final states, which are constructed by kinematic relations of 4-momentum vectors in different reference frames for all mother and daughter particles.
580

Evaluation of GUI technologies for CERN's Beam Interlock System

Skarhed, Tobias January 2023 (has links)
This thesis presents an evaluation of various graphical user interface (GUI) technologies for use in the supervision software of CERN’s Beam Interlock System (BIS). The evaluation is necessary because the current GUItechnology used by the supervision software, JavaFX, is no longer supported by Oracle. It also relies on aninternal library that is no longer maintained. Furthermore, a second version of the BIS is being developed, anda GUI is needed that works with BIS and BIS2 in parallel.Which technology is most suitable for the next version of the BIS supervision GUI?This question was answered by gathering user stories from users and experts. Simple proof of concepts weredeveloped for each technology, in order to identify technical limitations and register the development time. Theuser stories relevant to the choice of technology were listed, and each technology received points depending onwhether they were able to fulfill the requirement or not.Furthermore, in order to evaluate the ease of use, wireframes were created based on some of the user stories.These were qualitatively evaluated with stakeholders, which produced feedback that may be used for furtherdevelopment.Out of the four technologies evaluated, PyQt scored 6, ACW scored 4, WRAP scored 6 and Grafana scored3. WRAP and Grafana were discarded as viable options, since they were not able to fulfill hard requirements.ACW scored lower because it is web based and comes with a bigger maintenance overhead. / <p>This thesis was done as a part of a technical studentship at CERN.</p>

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