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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

VYUŽITÍ 3D TECHNOLOGIÍ VE VEŘEJNÉM PROSTORU / THE USE OF 3D TECHNOLOGY IN THE PUBLIC SPACE

Šebánek, Jan Unknown Date (has links)
The aim of this thesis is to define the impact of rapid prototyping technology in terms of creative potential to use this technology represents a particularly sculpture and architecture. Rapid Prototyping is a generic term covering a range of technologies: 3D scan converting the already realistic three-dimensional objects in computer memory, parametric modeling, which creates three-dimensional objects based on the formative algorithms, photogrammetry method of compiling three-dimensional object from a photo, technology, 3D printing materializing after each layer objects transferred from the computer's memory. When processing the theoretical work will be explored and discussed possibilities for realization of basic three-dimensional objects using 3D technology. The second step will be to map the different methods of access to artists working with 3D technology. In the end it tried to evaluate the benefits of these technologies in the field of sculpture and architecture in terms of traditional approaches. This paper attempts to describe the possible implications and potential of this progressive field in the classical artistic disciplines such as sculpture and architecture, both in terms of benefits and in terms of the eventual negative impact with respect to increasing the availability of this technology.
572

Návrh a realizace výroby konstrukce zubní náhrady / Proposal and Implementation of Production of Dental Plate Construction

Dusbaba, Michal January 2016 (has links)
This thesis deals with a CAD programmed construction design of dental prosthetics and its subsequent production by means of a five axis machine tool. In the theoretical part of the thesis one can find characteristics and analysis of materials designed for a production of dental prosthetics constructions. Among other things, the practical part of the thesis follows up digitization of a patient´s oral cavity part with the use of Trios intraoral scanner representing the latest scanning technology. The obtained data created a basis for a design of the respective dental prosthetics construction using the shape dental system programme called DentalDesigner 2015. Furthermore, the paper deals with a production of a dental prosthetics construction by means of a five axis machine tool and pursues completion works which resulted in the prosthetics final shape. The paper is concluded with discussion comprising a summary of results acquired in the practical part beginning from dental implant introduction to insertion of the made prosthetics construction into the patient´s oral cavity.
573

prodotti da forno innovativi / INNOVATIVE BAKERY PRODUCTS / innovative bakery products

GRUPPI, ALICE 17 April 2020 (has links)
L'obiettivo principale di questo progetto è quello di trovare diverse soluzioni per migliorare le caratteristiche tecnologiche, sensoriali, di sostenibilità e nutrizionali dei prodotti da forno. Come campione sono stati scelti i biscotti perché ampiamente consumati e rappresentano una buona fonte energetica, nonostante l'elevato contenuto di zuccheri e grassi. Sono state studiate diverse strategie. 1. Produzione di una farina funzionale grazie al condizionamento enzimatico del grano per ottenere una farina intera con una migliore qualità tecnologica e un migliore profilo nutrizionale. 3. Sostituzione dell'olio di palma con un ingrediente grasso più sostenibile e più sano, come l'olio extravergine di oliva, l'olio di vinaccioli, rispetto all'olio di girasole, ampiamente utilizzato. 3. Arricchimento con diversi ingredienti funzionali: a. proteine del siero di latte: l'idrolisi enzimatica è stata studiata come strategia per ottenere ingredienti proteici adatti a produrre biscotti; b. fibre: diverse fibre, principalmente derivate da sottoprodotti, sono state testate per valutare il loro potenziale ruolo come ingredienti funzionali per migliorare la consistenza e la stabilità ossidativa dei biscotti; c. estratto di buccia d'uva di scarto: la tecnologia di stampa 3D è stata utilizzata per ridurre l'effetto termico del processo di cottura sull'attività antiossidante di un estratto incapsulato aggiunto ai biscotti. / The main objective of this Ph.D. project was to find different solutions to improve the technological, sensorial, sustainability and nutritional characteristics of bakery products. Biscuits were used because of their characteristics: they are widely consumed and they are a good energy source, despite the high content in sugars and fats. Different strategies were investigated. 1. Production of a functional flour thanks to enzymatic conditioning of the wheat to obtain a whole flour with both better technological quality and improved nutritional profile for dietetic fibre composition and antioxidant compounds. 2. Substitution of palm oil with a more sustainable and healthier fat ingredient, such as extra virgin oil, grape seeds oil, in comparison with the widely used, sunflower oil. 3. Enrichment with different functional ingredients: a. whey proteins: enzymatic hydrolysis was investigated as a strategy to get protein ingredients suitable to produce acceptable high proteins biscuits; b. fibers: different fibres, mainly derived from by-products, were tested to evaluate their potential role as functional ingredients to improve texture and oxidative stability of biscuits; c. waste grape skins extract: 3D-printing technology was used to minimize the degradation effect of the baking process on antioxidant activity of an encapsulated grape-skin extract added to biscuits.
574

Évaluation de la technologie photonique sur silicium pour le développement de liens sans fil innovants visant 40 Gb/s au-delà de 200 GHz / Evaluation of silicon photonic technology for the development of innovative 40 Gbps wireless link above 200 GHz

Lacombe, Elsa 05 November 2018 (has links)
Avec l’explosion du trafic de données mobiles, des débits supérieurs au Gb/s deviennent nécessaires pour l’utilisateur. Ainsi, le réseau de communication est en cour d’amélioration afin de promouvoir le déploiement de la 5G, notamment grâce au développement et à l’installation de systèmes sans fil d’onde millimétrique (mmW) à 10 Gb/s. Néanmoins, pour délivrer de tels débits, les liens fronthaul/backhaul sans fil connectés au cœur de réseau devront supporter des flux de données supérieurs à 40 Gb/s. Cet enjeu suscite un intérêt croissant pour les fréquences sub-mmW et THz (0.1 THz – 1 THz) autour desquelles des bandes passantes (BPs) de 100 GHz sont accessibles. Il serait en effet possible d’atteindre un débit de 100 Gb/s, tout en utilisant des formats de modulation simples et ainsi réduire la consommation d’énergie du système. Visant le marché de masse des applications haut-débits, la technologie Photonique sur Silicium est particulièrement attractive pour générer des BPs naturellement larges et pour sa capacité à forts niveaux d’intégration et faible cout de fabrication. Dans cette thèse, une technologie Photonique sur Silicium industrielle a donc été évaluée durant le développement d’un émetteur intégré THz fonctionnant sur la base d’une photodiode et pouvant délivrer 100 Gb/s. Le développement d’une antenne THz faible cout et compacte est également un aspect majeur de cette thèse afin de permettre la transmission point-à-point du signal THz. En effet, une antenne intégrée sur substrat organique faible cout et à faibles pertes et une lentille fabriquée par impression 3D ont été développées afin d’évaluer ces technologies de prototypage industriel au-delà de 200 GHz. / With the booming of mobile data traffic, the need for higher data-rates is clearly felt. To cope with this strong demand and support the 5G roll-out, the capacity of the mobile communication network is being improved every day with many solutions, among which the development and installation of millimeterwave (mmW) wireless systems operating at up to 10 Gb/s. However, in order to deliver such high speeds to the user, the fronthaul/backhaul network sending data back to the core network would require above 40 Gb/s data-rate wireless links. This challenge generates a growing interest for sub-mmW and THz frequencies (0.1 THz – 1 THz) at which up-to 100 GHz bandwidth (BW) is accessible. In such BW, it would be possible to achieve up to 100 Gb/s data-rates while using simple modulation schemes to reduce the wireless system’s power consumption. Targeting mass-market high data-rates applications, Silicon Photonics technology seems very promising as it benefits from wide intrinsic BW and powerefficient components, as well as high integration levels and low manufacturing costs. In this context, a main aspect of this PhD project is the evaluation of an industrial Silicon Photonics technology for the development of a THz system-on-chip transmitter capable of reaching up to 100 Gb/s using a photodiode. Since THz antennas are also a hot topic for THz point-to-point transmission, a second aspect of this PhD study is the design of a low-cost and compact THz antenna-system. Hence, a planar antenna using low-loss organic packaging technology and a 3D-printed plastic lens were developed in order to assess those industrial prototyping techniques above 200 GHz.
575

Évaluation des technologies d'impression 3D pour le développement d'antennes directives à large bande passante pour les liaisons backhaul en bandes millimétriques V et E / Evaluation of 3D printing technologies for the development of wide-band directive antennas for millimeter wave backhaul links in E and V frequency bands

Nachabe, Nour 06 December 2018 (has links)
Face à la demande croissante de débits de données de plus en plus élevées, l’une des principales solutions proposées par la 5G est de densifier le réseau en y intégrant notamment de nouvelles « Small cells ». La réorganisation de l’architecture du réseau mobile pour s’adapter à l’intégration poussée de ces Small cells, fait naître la problématique de la connexion backhaul entre les stations de bases desservant les Small cells et le cœur de réseau. Ainsi, des liaisons backhaul de plusieurs Gb/s de données sont nécessaires pour pouvoir assurer un débit de données d’au moins 100Mb/s à l’utilisateur qui est l’un des objectifs fixés pour la 5G. Les solutions de connexion backhaul sans fils ont un avantage indiscutable face aux coûts de déploiements de fibres optiques qui sont très élevés. Pour augmenter la capacité spectrale des liaisons sans fils, l’utilisation des fréquences millimétriques au-delà de 6 GHz caractérisées par des larges bandes passantes sera prochainement discutée pour la 5G durant le World Radiocommunication Conference 2019. Parmi ces fréquences, les bandes V (57-66GHz) et E (71-76 GHz et 81-86 GHz) ont un intérêt indéniable grâce aux larges bandes passantes disponibles ainsi qu’aux conditions de licenciement peu exigeantes. Les travaux développés dans cette thèse consistent à concevoir des antennes directives à large bande passante permettant d’établir les liens backhaul point-à-point sans fils (LoS). En exploitant les technologies de fabrications à faibles coût telles que l’impression 3D et Printed Circuit Board (PCB) sur des substrats FR4, la conception de deux types d’antenne directives a été étudiée à savoir des antennes lentilles et des antennes réseaux. / In order to address the ever-increasing demand of higher data rates, adding small cells to the existing macrocells infrastructure is one of the most important milestones of the 5G roadmap. With the integration of small cells and the re-organization of the network topology, backhaul bottleneck is the main challenge to address in the near future. Facing the costs of deployments of fiber optic connections, point-to-point wireless backhaul links using millimeter wave (mmW) frequencies are gaining prominence. 5G future frequencies, to be discussed under the World Radiocommunication Conference 2019 (WRC-19) open-up the way towards mmW frequency band where large bandwidths are naturally available. The high bandwidths available at these frequencies enable several Gbps data rate backhaul links, which is un utmost necessity to respect the 100 Mbps user-experienced data rate promised by the 5G standard. Millimeter-wave frequencies in V and E-bands unlicensed/light licensed spectrum are considered as primary candidates for backhaul links. In addition to the light license regime, the high free space path loss experienced at these frequencies is rather beneficial to limit the interference between small cells links. Moreover, the high available bandwidths at V and E-bands enable to achieve multi Gb/s links without using complex modulation schemes. In this thesis, we focused our research study on developing high gain wide-band antennas usable in point-to-point backhaul links in a Line of Sight (LoS) context. Leveraging cost-efficient technologies like 3D printing and Printed Circuit Board (PCB) on FR4 substrates, we studied two high-gain antenna types: lens antennas and flat array antennas.
576

Aufbereitung von 3D-Scandaten zur additiven Fertigung von orthopädischen Helmschalen mit Fusion 360 und Geomagic FreeForm

Matthes, Jörg, Petzold, Claudius, Mauersberger, Valentin 05 July 2019 (has links)
Im Rahmen des Forschungsprojektes ,,Entwicklung eines 3D Hochgeschwindigkeits-Rotationsdruckverfahren' an der Hochschule Mittweida, wird sich mit dem Erzeugen eines CAD-Modells eines Patientenschädels und der passgenauen Modellierung einer orthopädischen Helmschale für diesen beschäftigt. Ziel ist es die zeitintensive Modellherstellung mittels Gips einzusparen und die endgültige Helmschale im .stl-Format zu erzeugen. Weiter wird, mittels einer visuellen Programmierumgebung, ein Programm erzeugt um die Helmschale in einem polaren Koordinatensystem für den geplanten Hochgeschwindigkeits-Rotations-3D-Drucker auszurichten, zu slicen und die Koordinaten der einzelnen Punkte der Bahnkurven der Extruder auszugeben.
577

Moderní pomůcky ve výuce chemie / Modern teaching aids in chemistry education

Míka, Luděk January 2017 (has links)
No description available.
578

Learning Multi-step Dual-arm Tasks From Demonstrations

Natalia S Sanchez Tamayo (9156518) 29 July 2020 (has links)
Surgeon expertise can be difficult to capture through direct robot programming. Deep imitation learning (DIL) is a popular method for teaching robots to autonomously execute tasks through learning from demonstrations. DIL approaches have been previously applied to surgical automation. However, previous approaches do not consider the full range of robot dexterous motion required in general surgical task, by leaving out tooltip rotation changes or modeling one robotic arm only. Hence, they are not directly applicable for tasks that require rotation and dual-arm collaboration such as debridement. We propose to address this limitation by formulating a DIL approach for the execution of dual-arm surgical tasks including changes in tooltip orientation, position and gripper actions.<br><br>In this thesis, a framework for multi-step surgical task automation is designed and implemented by leveraging deep imitation learning. The framework optimizes Recurrent Neural Networks (RNNs) for the execution of the whole surgical tasks while considering tooltip translations, rotations as well as gripper actions. The network architecture proposed implicitly optimizes for the interaction between two robotic arms as opposed to modeling each arm independently. The networks were trained directly from the human demonstrations and do not require to create task specific hand-crafted models or to manually segment the demonstrations.<br><br>The proposed framework was implemented and evaluated in simulation for two relevant surgical tasks, the peg transfer task and the surgical debridement. The tasks were tested under random initial conditions to challenge the robustness of the networks to generalize to variable settings. The performance of the framework was assessed using task and subtask success as well as a set of quantitative metrics. Experimental evaluation showed favorable results for automating surgical tasks under variable conditions for the surgical debridement, which obtained a task success rate comparable to the human task success. For the peg transfer task, the framework displayed moderate overall task success. Quantitative metrics indicate that the robot generated trajectories possess similar or better motion economy that the human demonstrations.
579

Gjutning av rostfritt stål med 3D-printade sandformar / Stainless steel casting with 3D printed sand molds

Lindqvist, Olle, Thulin, Gustaf January 2020 (has links)
Sand mold casting is a manufacturing method that has been used for thousands of years. In recent years additive manufacturing has, among other things, enabled production of sand molds with complex geometry resulting in castings with geometry that would have been very hard, if not impossible, to produce with conventional sand mold casting or machining procedures. Since this manufacturing method is relatively new, knowledge gaps exist regarding the benefits and drawbacks of the method as well as when it should be used. The purpose of this study has been to explore casting molds produced by additive manufacturing, how they can be used and what effect they have on the manufactured product. For this purpose, a existing product has been redesigned to be cast in one of these molds instead of traditionally being machined from large aluminium blocks. The design work has been supplemented with calculations on the parts structural integrity, interviews and material sample tests. The redesign was made on behalf of Vattenfall AB and the studied component was a part of a test rig for a hydro power plant called spiral casing. The result of the study is a new design of the spiral casing with a lower weight and volume, made with stainless steel instead of aluminium, and other improvements. Testing of cast samples have shown that the mechanical properties of steel cast in 3D-printed and conventionally manufactured sand molds do not differ significantly. The sample cast in a 3D-printed mold did have a finer surface finish however.  Production volume, product complexity, material and lead time are all factors that determine when additive manufacturing should be used in the creation of sand molds. Further studies are required to better determine where the breakeven points are.
580

Toward a Network Based 3D Printing Service

Ndikuriyo, Laurier, Abdulla, Mohammad January 2013 (has links)
This bachelor’s thesis has given us an opportunity to gain insight into how to create a service from scratch and to develop it into a fully functional service. The 3D printer service starts when a customer uploads a file containing the 3D design that they want to have made via a website. The file is stored and the printing request is placed into a queue. After that the client simply waits until the object is printed, with all of the various steps being handled automatically. The uploaded file containing the 3D design is automatically converted into Gcode by using the software Skeinforge. Gocde is the language that the printer interprets. The printer itself is controlled by the ReplicatorG program. The ReplicatorG program transfers the Gcode commands to the printer to print the desired object. This Gcode includes commands to warm up the automated build platform where the object will be created and to warm up the extruder head – through which plastic will be extruded to create the 3D object. If the customer wants to see the object while it is being printed – we have made this possible via a network attached camera. This camera is placed next to the printer. Once the object has been printed the automated build platform is allowed to cool and a motor driven belt advances to eject the object from the platform. In an ideal system the object would be put directly into a bag or other package – with a pre-printed label, thus it would be ready for shipping to the customer. This portion of the system has not yet been realized and is left as future work. / Detta kandidatexamensarbete har gett oss en möjlighet att få en inblick i hur det är att skapa en tjänst från grund och sedan bygga på den tills en fullt fungerande tjänst var skapad. 3D printertjänsten drar igång då en kund laddar upp den önskade filen via hemsidan, som sedan lagras och läggs i en eventuell kö. Från detta behöver inte kunden eller någon annan göra något mer utan allt sköts automatiskt. En konvertering av kundens STL fil till språket Gcode som skrivaren kan tolka sker med hjälp av programmet Skeinforge. Själva skrivaren styrs av programmet ReplicatorG där allt bestäms och slutligen ger order till skrivaren att börja skriva ut det som önskas. Om kunden vill så finns en möjlighet att med hjälp av en IP kamera även se sina produkter live då de tillverkas. Idén om att obtjekt direkt ska landa i en förpackning som är redo att skickas till kunden lämnas för framtida arbeten.

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