Phoenix Encircled by White Dragon

This design combines Chinese cultural symbols with three dimensional geometry to create a soft sculpture. Specifically, the purpose of the design was to 1) transfer Chinese cultural symbols into a dress and 2) explore geometrical shape to create cohesive art-wear. This asymmetrical garment design consists of three layers of designs: a transparent dress, a phoenix, and a Chinese dragon. A white dragon coiled around a transparent dress, which is decorated by phoenix feathers and wings. A contrast effect was created by the solid white cotton fabric and the transparent fabric. Hundreds of dragon scales and dozens of dragon fins were placed on the coiled dragon body, creating a flying, repetition, and rhythm pattern. Visually, the coiled 3D dragon, the phoenix plumes and wings, the contrast texture between solid cotton and transparent fabric, and the unique design shape created a harmonic design effect together

Drishti, a volume exploration and presentation tool

Among several rendering techniques for volumetric data, direct volume rendering is a powerful visualization tool for a wide variety of applications. This paper describes the major features of hardware based volume exploration and presentation tool - Drishti. The word, Drishti, stands for vision or insight in Sanskrit, an ancient Indian language. Drishti is a cross-platform open-source volume rendering system that delivers high quality, state of the art renderings. The features in Drishti include, though not limited to, production quality rendering, volume sculpting, multi-resolution zooming, transfer function blending, profile generation, measurement tools, mesh generation, stereo/anaglyph/crosseye renderings. Ultimately, Drishti provides an intuitive and powerful interface for choreographing animations

Using digital and hand printing techniques to compensate for loss: re-establishing colour and texture in historic textiles

Conservators use a range of 'gap filling' techniques to improve the structural stability and presentation of objects. Textile conservators often use fabric supports to provide reinforcement for weak areas of a textile and to provide a visual infill in missing areas. The most common technique is to use dyed fabrics of a single colour but while a plain dyed support provides good reinforcement, it can be visually obtrusive when used with patterned or textured textiles. Two recent postgraduate dissertation projects at the Textile Conservation Centre (TCC) have experimented with hand printing and digital imaging techniques to alter the appearance of support fabrics so that they are less visually obtrusive and blend well with the colour and texture of the textile being supported. Case studies demonstrate the successful use of these techniques on a painted hessian rocking horse and a knitted glove from an archaeological context

Double-exchange theory of ferroelectric polarization in orthorhombic manganites with twofold periodic magnetic texture

We argue that many aspects of improper ferroelectric activity in orthorhombic manganites can be rationalized by considering the limit of infinite intra-atomic splitting between the majority- and minority-spin states (or the double exchange limit), which reduces the problem to the analysis of a spinless double exchange (DE) Hamiltonian. We apply this strategy to the low-energy model, derived from the first-principles calculations, and combine it with the Berry-phase theory of electric polarization. We start with the simplest two-orbital model, describing the behavior of the eg bands, and apply it to the E-type antiferromagnetic (AFM) phase, which in the DE limit effectively breaks up into one-dimensional zigzag chains. We derive an analytical expression for the electronic polarization (Pel) and explain how it depends on the orbital ordering and the energy splitting Delta between eg states. Then, we evaluate parameters of this model, starting from a more general five-orbital model for all Mn 3d bands and constructing a new downfolded model for the eg bands. From the analysis of these parameters, we conclude that the behavior of Pel in realistic manganites corresponds to the limit of large Delta. We further utilize this property in order to derive an analytical expression for Pel in a general two-fold periodic magnetic texture, based on the five-orbital model and the perturbation-theory expansion for the Wannier functions in the first order of 1/Delta. This expression explains the functional dependence of Pel on the relative directions of spins. Furthermore, it suggests that Pel is related to the asymmetry of the transfer integrals, which should simultaneously have symmetric and antisymmetric components. Finally, we explain how the polarization can be switched between orthorhombic directions a and c by inverting the zigzag AFM texture in every second ab plane.Comment: 41 page, 10 figure

On the Optimization of Visualizations of Complex Phenomena

The problem of perceptually optimizing complex visualizations is a difficult one, involving perceptual as well as aesthetic issues. In our experience, controlled experiments are quite limited in their ability to uncover interrelationships among visualization parameters, and thus may not be the most useful way to develop rules-of-thumb or theory to guide the production of high-quality visualizations. In this paper, we propose a new experimental approach to optimizing visualization quality that integrates some of the strong points of controlled experiments with methods more suited to investigating complex highly-coupled phenomena. We use human-in-the-loop experiments to search through visualization parameter space, generating large databases of rated visualization solutions. This is followed by data mining to extract results such as exemplar visualizations, guidelines for producing visualizations, and hypotheses about strategies leading to strong visualizations. The approach can easily address both perceptual and aesthetic concerns, and can handle complex parameter interactions. We suggest a genetic algorithm as a valuable way of guiding the human-in-the-loop search through visualization parameter space. We describe our methods for using clustering, histogramming, principal component analysis, and neural networks for data mining. The experimental approach is illustrated with a study of the problem of optimal texturing for viewing layered surfaces so that both surfaces are maximally observable