702,606 research outputs found
Themes of drawing and digital context: student engagement with theory and practice using the tool of the integrated learning portfolio
This article presents a reflective visual narrative documenting the learning encounters of BA (Hons) Surface Design undergraduates using the Integrated Learning Portfolio (ILP) tool in Year one. Theoretical themes of drawing, digital drawing design practice, and visual design research experientially blended the physical and the virtual learning tools, environments and collaborative culture through this integrated first year route. Parallel theory and practice on specific themes such as âdrawing lines within the urban landscapeâ, âcreating shadow silhouettesâ, âusing the body as a tool for drawingâ, and âcultivating fortuitous accidents in drawing practiceâ, created a conceptual space for students to evaluate the future relevance of these drawing experiences within the context of their design programme
Hidden surface line drawing algorithm
technical reportThis paper describes a fast procedure in processing hidden surface pictures with the output in vector form. The program has been written expressly for a Decsystem 10 and has performed successfully on three different installations. The algorithm which is being used is a modification to the Watkins' Algorithm. Consequently, the program has inherited many key features which provide for speed, compactness, and flexibility
The drawing of experimental curves
This report presents a discussion of how to determine the location of a line or surface from experimental data. What we desire to know practically is the number of ordinates required to obtain a certain probable precision in drawing a line or surface
Anisotropic super-attenuation of capillary waves on driven glass interfaces
Metrological AFM measurements are performed on the silica glass interfaces of
photonic band-gap fibres and hollow capillaries. The freezing of attenuated
out-of-equilibrium capillary waves during the drawing process is shown to
result in a reduced surface roughness. The roughness attenuation with respect
to the expected thermodynamical limit is determined to vary with the drawing
stress following a power law. A striking anisotropic character of the height
correlation is observed: glass surfaces thus retain a structural record of the
direction of the flow to which the liquid was submitted
The -genus of Kuratowski minors
A drawing of a graph on a surface is independently even if every pair of
nonadjacent edges in the drawing crosses an even number of times. The
-genus of a graph is the minimum such that has an
independently even drawing on the orientable surface of genus . An
unpublished result by Robertson and Seymour implies that for every , every
graph of sufficiently large genus contains as a minor a projective
grid or one of the following so-called -Kuratowski graphs: , or
copies of or sharing at most common vertices. We show that
the -genus of graphs in these families is unbounded in ; in
fact, equal to their genus. Together, this implies that the genus of a graph is
bounded from above by a function of its -genus, solving a problem
posed by Schaefer and \v{S}tefankovi\v{c}, and giving an approximate version of
the Hanani-Tutte theorem on orientable surfaces. We also obtain an analogous
result for Euler genus and Euler -genus of graphs.Comment: 23 pages, 7 figures; a few references added and correcte
The development of a finite elements based springback compensation tool for sheet metal products
Springback is a major problem in the deep drawing process. When the tools are released after the forming stage, the product springs back due to the action of internal stresses. In many cases the shape deviation is too large and springback compensation is needed: the tools of the deep drawing process are changed so, that the product becomes geometrically accurate after springback. In this paper, two different ways of geometric optimization are presented, the smooth displacement adjustment (SDA) method and the surface controlled overbending (SCO) method. Both methods use results from a finite elements deep drawing simulation for the optimization of the tool shape. The methods are demonstrated on an industrial product. The results are satisfactory, but it is shown that both methods still need to be improved and that the FE simulation needs to become more reliable to allow industrial application
Copper-acrylic enamel serves as lubricant for cold drawing of refractory metals
Acrylic enamel spray containing metallic copper pigment lubricates refractory metal tubing during cold drawing operations so that the tubing surface remains free from scratches and nicks and does not seize in the die. Zirconium alloys, zirconium, tantalum alloys, niobium alloys, vanandium alloys and titanium alloys have been drawn using this lubricant
Counterexample to an extension of the Hanani-Tutte theorem on the surface of genus 4
We find a graph of genus and its drawing on the orientable surface of
genus with every pair of independent edges crossing an even number of
times. This shows that the strong Hanani-Tutte theorem cannot be extended to
the orientable surface of genus . As a base step in the construction we use
a counterexample to an extension of the unified Hanani-Tutte theorem on the
torus.Comment: 12 pages, 4 figures; minor revision, new section on open problem
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