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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.
71

An exploration of digital technology over a number of manipulated textile surfaces

Ryall, Helen January 2010 (has links)
Ink jet printing for textiles has brought many benefits to the textile print industry. It has an ability to print on demand, using thousands of colours, and at reduced costs compared with rotary screenprinting for small scale production, ink jet technology has already established itself as a reliable method of printing for the textile industry. This research investigates a new approach to ink jet technology. Numerous new surfaces are fed through a textile ink jet printer in the generation of bespoke printed textiles. This is an experimental approach to textile ink jet printing, recording practical solutions, and uncovering innovative processes for a new direction for digital technology for textiles. Various surfaces have been enhanced using screen print techniques and embroidery, or manipulated by hand and digitally printed in the production of an array of unique digital resist techniques. This research combines the use of textile hand craftsmanship with digital technology, crossing the boundaries and discovering ways of combining these disciplines. This research will highlights some of the possibilities with applying a hand crafted approach to ink jet technology for textiles, it demonstrate the control of colour, resist effects and the sensitivity of design which can be achieve using these new processes. In addition to this, the research will demonstrate the added value of this crafted approach to digital design, as well discussing the potential for reproducing these complex textile craft techniques and digital resist effects using CAD and ink jet technology.
72

FutureFactories : the application of random mutation to three-dimensional design

Dean, Lionel Theodore January 2009 (has links)
The title of the project, ‘FutureFactories’, describes an exploration of direct digital manufacturing and the use of this technology in creating new models for consumer product design practice. In additive fabrication itself, there is no economic advantage in producing identical artefacts: given this, and the free-form potential of a technology that can deliver almost any form imaginable, the project examines the possibility of modifying the design with every artefact produced. The aim is to create automated systems capable of volume production, establishing mass individualisation: the industrial scale production of one-off artefacts. This work explores the potential to combine parametric CAD modelling with computer programming to create animated meta-designs that change in real time. These scripts introduce a random computer generated element into each physical product ‘printed out’ using direct digital manufacturing. The intention is to combine qualities normally associated with the vagaries of the hand-made with the technical resolution of industrial mass-manufacture; whilst at the same time maintaining a coherent design and identity. The outputs from this practice-based research project consist of inspirational products ranging from gallery pieces to commercial retail products and, alongside the real-world artefacts, the scripted meta-designs from which they are created. The use of such software processes and real-time networks as generative tools, questions existing transient boundaries of practice, and exposes the irrelevance of conventional definitions of role. It is clear that the outcomes of such a new model of creative production cannot be thought of as traditionally conceived pieces. The outcomes of the research suggest that the resulting artefacts can be considered both functionally useful and as art. Outside of that, existing definitions convey little of the reality of their production, as they lie in some new, as yet unspecified, arena of production.
73

Aplikace CAD/CAM softwaru PowerMILL při obrábění / Application CAD/CAM software PowerMILL for machining

Spáčil, Petr January 2010 (has links)
roject own model of workpiece. Choose competent machine tools for machining. Strategy analysis of machining in software PowerMILL. NC programs processing for given application. Experimental verification of NC programs with system Sinumerik 840D.
74

3D gravírovací frézka / 3D engraving milling machine

Bosák, Daniel January 2014 (has links)
This thesis deals with rebuilding of a laboratory manipulator to 3D engraving machine. First part of the thesis describes the engraving technology and lists the most common types of engraving machines. Next, the initial state of the machine is analysed and modifications of mechanical and electrical equipment are suggested. Design, realisation of a control system and human machine interface are described. The Beckhoff TwinCAT programming environment is used. The last part of the thesis deals with practical realisation and commissioning of the machine. The results of the thesis can be used as an addition for lessons of Automation of Production Machines.
75

Návrh designu a technologie výroby stupaček pro cestovní enduro / Draft of design and manufacturing technology for the enduro footrests

Vrzal, Jan January 2016 (has links)
The diploma thesis is focused on draft of footrests for endure Honda Transalp XL700V of 2008. Attention is paid to the draft of the design of the footrest which is, which is designed for driving in light off-road. There is also described the issue if the choice of the material from aluminium alloy and the verification of the methods of the designed geometry using FEM and Rapid Prototyping. The experimental part deals with the design of appropriate tools and cutting conditions and with the creation of the NC program in ShopMill. There is enclosed the technical documentation and the NC program in the final part.
76

Analysis and time calculations of NC files : Time calculation of Nailing Bridge machine movements

Rohnér, Julia, Sköld, Emelie January 2023 (has links)
Randek is a company that develops machines. The machines are used to build prefabricated houses. They have developed a CNC machine called Nailing Bridge that creates house walls. One of their issues is that they must predict the time it takes to build a wall because their customers need to know how long it takes to deliver their house. Our project solves this problem by making a program that calculates the time it takes to build a wall on the Nailing Bridge with help from NC files (Numerical Control files) consisting of G-code. One NC file contains the machine's operations, such as sawing, nailing, and routing. The goal was to develop a program with a maximum margin of error of 3% from reality. The machine was tested to measure the time of different operations to develop the program, and the NC files were analysed. Calculations for the jerk, acceleration, deceleration, and velocity of the CNC machine were considered to predict the time of the movements with high enough precision. The calculations and implementation are written in C#. A GUI is created for the user to use the program easily. The end product is a program that can take in one NC file and gives output on the time it should take for the Nailing Bridge to go through the file. The margin of error was between 5% to 31% for one operation of sawing or nailing, which is significantly higher than the goal of 3%. The program was therefore debugged with unit testing and new tests of the Nailing Bridge to find the sources for this margin of error. The conclusion is that the program works but not exactly to the company's standards.
77

Synthesis and Photophysical Properties of Porphyrin-Containing Supramolecular Systems

Altamimi, Rashid M. 03 December 2010 (has links)
No description available.
78

MODELING OF I/O BLOCK AND SWITCH BLOCK FOR SECOND GENERATION MULTI-TECHNOLOGY FIELD PROGRAMMABLE GATE ARRAY (MT-FPGA)

SAMSANI, SIVA PRASAD REDDY 03 April 2006 (has links)
No description available.
79

Life history and production of the dominant Chironomidae in the New River, with emphasis on the effects of Bacillus thuringiensis var. Israelensis

Silvia, Antone G. 09 May 2009 (has links)
The effects of Bacillus thuringiensis var. israelensis (Bti) on chironomid production was assessed in the New River in southern West Virginia. Production was measured in a year without Bti treatment (1987) and a year with treatment (1988). Sampling was conducted from June through November at Sandstone Falls, 16 km below Bluestone Dam in Summers County. Sampling was restricted to rock outcrops covered with Podostemum (river weed). Samples were collected at 2- wk intervals with a quantitative device that delineates an area of 0.01 m². Three species belonging to two genera accounted for about two-thirds of chironomid production in both years. Cohort production intervals were estimated to be 27 d for both species of Cricotopus and 20 d for P. convictum. Total chironomid production from June through November 1987 was 10.8 g/m² and during the same period in 1988 was 33.8 g/m². In 1987, the production of C. bicinctus and Cc. politus was 4.09 g/m² (38% of total chironomid production), and production of P. convictum was 2.46 g/m² (23%). In 1988, the production of C. bicinctus and C. politus was 12.39 g/m² (37%), and production of P. convictum was 11.38 g/m² (34%). Bti treatments caused no adverse effect on chironomid production in 1988, because the same species were dominant and their production was 3X higher. In addition, density and mean individual biomass were greater in 1988 than in 1987. The production increase in 1988 was probably related to environmental factors other than Bti treatments, such as discharge and Podostemum standing stock. / Master of Science
80

Croissance et réactivité du silicène / Growth and reactivity of silicene

Tchalala, Mohamed Rachid 24 October 2014 (has links)
L’objet de cette thèse est l’étude de la croissance de silicène sur des substrats d’argent,ainsi que l’étude de sa réactivité vis-à-vis de l’oxygène. La croissance a été réalisée sous ultra-vide et contrôlée par spectroscopie d’électrons Auger (AES) et par diffraction d’électrons lents (LEED). Les structures obtenues et leurs réactivités à l’oxygène ont été étudiées par microscopie à champ proche (STM et nc-AFM) et par spectroscopie de photoémission résolue en angle (ARPES). Nous avons étudié la structure interne des nano-rubans de silicène auto-assemblés sur un substrat d’Ag(110). Sur Ag(111) nous obtenons un feuillet de silicène qui présente différentes structures en fonction de la température du substrat. L’étude de la réactivité des rubans et des feuillets a montré que le silicène formé sur substrat d’argent est relativement stable vis-à-vis de l’oxygène ce qui ouvre des perspectives de fonctionnalisation du silicène. La dernière partie de cette thèse concerne la synthèse de feuillets de silicium par voie chimique. Nous avons mis au point une nouvelle méthode prometteuse de synthèse chimique qui nous a permis de synthétiser des feuillets de silicium de structure graphitique. / The objective of this thesis is the study of the growth of silicene on silver substrates as well as its reactivity towards the oxygen. The growth was performed under ultra-high vacuum and controlled by Auger electrons spectroscopy (AES) and low energy electrons diffraction (LEED). The obtained structures and their relativities towards the oxygen were studied by near field microscopy (STM and nc-AFM) and by angle resolved electrons photoemission spectroscopy (ARPES). We have studied the internal structure of the selfassembled silicene nanoribbons on Ag(110) substrate. On Ag(111), we have obtained a silicene sheet presenting different structures versus the temperature of the substrate. The reactivity of silicene nanoribbons and sheets grown on silver show that silicene is relatively stable towards the oxygen which opens a new perspectives of functionalization of the silicene. The last part of this thesis concerns the synthesis of silicone sheets by chemical process. We have develpped a new promising process of chemical synthesis which allowed us to synthesize silicon sheets with graphitic structure.

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