One idea common in the computer industry today is that by the time a technological innovation reaches the mass market it is already obsolete. News of recent technological developments race quickly through the computer industry, creating large scale competition among various businesses for the dollars of both educational institutions and industries. In an effort to produce sophisticated and powerful software readily accessible to users whose area of expertise is not programming, software developers have increasingly turned toward the simplest form of language and concept representation--the icon. As icons become increasingly sophisticated and their function grows, so will their availability in various interfaces. The number of users who operate them will also increase. Advanced help systems and animation will assist in relieving some difficulties while creating others. In either case, icon recognizability will be a crucial factor for anyone (novice or expert) who will use them. The purpose of this study was to verify whether all users unfamiliar with a graphical user interface (GUI) system, specifically icons, will require assistance with 40' "W those icons that are unrecognizable in either form or function. Based on the results of this study, an icon recognizability does exist among different groups of computer users. This recognizability is based upon the experience of the users and not upon the type of software they may use most often.

Mobile devices such as cell phones, personal digital assistants (PDAs), and laptops continue to increase in memory and processor speed at a rapid pace. In recent years it has become common for users to check their email, browse the internet, or play music and movies while traveling. The performance gains are also making mobile graphics renderers more viable applications. However, the underlying battery technology that powers mobile devices has only tripled in capacity in the past 15 years whereas processor speeds have seen a 100-fold increase in the same period. Photon mapping, an extension of ray-tracing, is a robust global illumination algorithm used to produce photorealistic images. Photon mapping, like ray-tracing, can render high-quality specular highlights, transparent and reflective materials, and soft shadows. Complex effects such as caustics, participating media, and subsurface scattering can be rendered more efficiently using photon mapping. This work profiles the energy use of a photon-mapping based renderer to first establish what aspects require the most energy. Second, the effect several photon mapping settings have on image quality is measured. Reasonable tradeoffs between energy savings and moderately diminished image quality can then be recommended, making photon mapping more viable on mobile devices. Our results show that image quality is affected the least as settings corresponding to final gather computations are adjusted. This implies that a user can trade a modest decrease in image quality for significant gains in energy efficiency. Suggestions are made for using energy more efficiently when rendering caustics. Results also show that, although overall energy use is higher with larger image resolutions, per-pixel energy costs are cheaper.

In this thesis we study the isoperimetric problem on trees and graphs with bounded treewidth. Let G = (V,E) be a finite, simple and undirected graph. For let δ(S,G)= {(u,v) ε E : u ε S and v ε V – S }be the edge boundary of S. Given an integer i, 1 ≤ i ≤ | V| , let the edge isoperimetric value of G at I be defined as be(i,G)= mins v;|s|= i | δ(S,G)|. For S V, let φ(S,G) = {u ε V – S : ,such that be the vertex boundary of S. Given an integer i, 1 ≤ i ≤ | V| , let the vertex isoperimetric value of G at I be defined as bv(i,G)= The edge isoperimetric peak of G is defined as be(G) =. Similarly the vertex isoperimetric peak of G is defined as bv(G)= .The problem of determining a lower bound for the vertex isoperimetric peak in complete k-ary trees of depth d,Tdkwas recently considered in[32]. In the first part of this thesis we provide lower bounds for the edge and vertex isoperimetric peaks in complete k-ary trees which improve those in[32]. Our results are then generalized to arbitrary (rooted)trees. Let i be an integer where . For each i define the connected edge isoperimetric value and the connected vertex isoperimetric value of G at i as follows: is connected and is connected A meta-Fibonacci sequence is given by the reccurence a(n)= a(x1(n)+ a1′(n-1))+ a(x2(n)+ a2′(n -2)), where xi: Z+ → Z+ , i =1,2, is a linear function of n and ai′(j)= a(j) or ai′(j)= -a(j), for i=1,2. Sequences belonging to this class have been well studied but in general their properties remain intriguing. In the second part of the thesis we show an interesting connection between the problem of determining and certain meta-Fibonacci sequences. In the third part of the thesis we study the problem of determining be and bv algorithmically for certain special classes of graphs. Definition 0.1. A tree decomposition of a graph G = (V,E) is a pair where I is an index set, is a collection of subsets of V and T is a tree whose node set is I such that the following conditions are satisfied: (For mathematical equations pl see the pdf file)

Thesis (M.F.A.)--Rochester Institute of Technology, 2008. / Typescript. Includes bibliographical references (leaf 50).

The objective of the study is to utilize the cross-sectional computation capabilities of a computer to calculate the revolutions per minute, to determine the volume of metal being removed by the machine cutter at any point in the programmed path, and to output the feed rate that the particular situation requires. The six chapters which present the information are as follows: Chapter I, introduction; Chapter II, analysis of factors affecting the computation of speed and feed rate parameters; Chapter III, organization of the input by the numerical control programmer; Chapter IV, modifications to the computer software; Chapter V, evaluation of the benefits of utilizing computed speed and feed rates; Chapter VI, summary, findings, conclusions, and recommendations.

<p>3D character modeling is a crucial process of asset creation in the entertainment industry, particularly for animation and games. A fully automated pipeline via sketch-based 3D modeling (SBM) is an emerging possibility, but development is stalled by unrefined outputs and a lack of character-centered tools. This thesis proposes an improved method for constructing 3D character models with minimal user input, using only two sketch inputs  i.e., a front and side unshaded sketch. The system implements a deep convolutional neural network (CNN), a type of deep learning algorithm extending from artificial intelligence (AI), to process the input sketch and generate multi-view depth, normal and confidence maps that offer more information about the 3D surface. These are then fused into a 3D point cloud, which is a type of object representation for 3D space. This point cloud is converted into a 3D mesh via an occupancy network, involving another CNN, for a more precise 3D representation. This reconstruction step contends with non-deep learning approaches such as  Poisson reconstruction. The proposed system is evaluated for character generation on standardized quantitative metrics (i.e., Chamfer Distance [CD], Earth Mover’s Distance [EMD], F-score and Intersection of Union [IoU]), and compared to the base framework trained on the same character sketch and model database. This implementation offers a  significant improvement in the accuracy of vertex positions for the reconstructed character models. </p>

<p dir="ltr">This study provides insights into the right combination of devices in a co-design task, in this case, at designing a game level. The cross-reality systems enable users to connect and collaborate across the Reality-Virtuality continuum i.e., PC/Desktop, augmented reality (AR), mixed reality (MR) and virtual reality (VR). Co-design involves two or more users coming together to ideate a clear objective, and build using the appropriate tools for collaboration, design, testing, and refinement for the masses. It also considers the time and resources used throughout the process with constant and open communication. The simulation design is based on developing an application that allows two users to connect in a pairwise modality (Desktop-Desktop, VR-VR or Desktop-VR) and use the assets provided to design a game level. The users were given a layout of the level and factors based on which the level will be designed. The results are discussed, and future work and conclusions are provided based on them.</p>

Call number: LD2668 .T4 1985 H33 / Master of Landscape Architecture

Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Subdivision is an important and e cient tool for rendering smooth curves and surfaces in computer graphics, by repeatedly applying a subdivision (re ning) scheme to a given set of points. In the literature, attention has been mostly restricted to developing binary subdivision schemes. The primary emphasis of this thesis is on ternary subdivision, and in particular on the interpolatory case. We will derive a symmetric ternary interpolatory subdivision scheme for the rendering of curves, satisfying analogous properties to the Dubuc-Deslauriers binary scheme. Explicit construction methods, as well as a corresponding convergence analysis, will be presented. Graphical illustrations of the results will also be provided. / AFRIKAANSE OPSOMMING: Subdivisie bied 'n belangrike en doeltre ende metode om gladde krommes en oppervlakke in rekenaargra ka te genereer. Hierdie metode behels dat 'n subdivisieskema (of verfyningskema) herhaaldelik toegepas word op 'n gegewe versameling punte. In die literatuur word daar hoofsaaklik gefokus op die ont- wikkeling van bin^ere subdivisieskemas. In hierdie tesis word die klem gel^e op tern^ere subdivisieskemas, en in die besonder op interpolerende skemas. Ons sal 'n simmetriese tern^ere interpolerende subdivisieskema, wat analo e eienskappe as di e van die Dubuc-Deslauriers bin^ere skema bevredig, ontwikkel, om krom- mes te lewer. Eksplisiete konstruksiemetodes en ooreenkomstige konvergensie- analise, asook gra ese illustrasies van die resultate, sal getoon word.

This research investigates how shifts in perception might be brought about through the development of visual imagery created by the use of virtual environment technology. Through a discussion of historical uses of immersion in art, this thesis will explore how immersion functions and why immersion has been a goal for artists throughout history. It begins with a discussion of ancient cave drawings and the relevance of Plato’s Allegory of the Cave. Next it examines the biological origins of “making special.” The research will discuss how this concept, combined with the ideas of “action” and “reaction,” has reinforced the view that art is fundamentally experiential rather than static. The research emphasizes how present-day virtual environment art, in providing a space that engages visitors in computer graphics, expands on previous immersive artistic practices. The thesis examines the technical context in which the research occurs by briefly describing the use of computer science technologies, the fundamentals of visual arts practices, and the importance of aesthetics in new media and provides a description of my artistic practice. The aim is to investigate how combining these approaches can enhance virtual environments as artworks. The computer science of virtual environments includes both hardware and software programming. The resultant virtual environment experiences are technologically dependent on the types of visual displays being used, including screens and monitors, and their subsequent viewing affordances. Virtual environments fill the field of view and can be experienced with a head mounted display (HMD) or a large screen display. The sense of immersion gained through the experience depends on how tracking devices and related peripheral devices are used to facilitate interaction. The thesis discusses visual arts practices with a focus on how illusions shift our cognition and perception in the visual modalities. This discussion includes how perceptual thinking is the foundation of art experiences, how analogies are the foundation of cognitive experiences and how the two intertwine in art experiences for virtual environments. An examination of the aesthetic strategies used by artists and new media critics are presented to discuss new media art. This thesis investigates the visual elements used in virtual environments and prescribes strategies for creating art for virtual environments. Methods constituting a unique virtual environment practice that focuses on visual analogies are discussed. The artistic practice that is discussed as the basis for this research also concentrates on experiential moments and shifts in perception and cognition and references Douglas Hofstadter, Rudolf Arnheim and John Dewey. iv Virtual environments provide for experiences in which the imagery generated updates in real time. Following an analysis of existing artwork and critical writing relative to the field, the process of inquiry has required the creation of artworks that involve tracking systems, projection displays, sound work, and an understanding of the importance of the visitor. In practice, the research has shown that the visitor should be seen as an interlocutor, interacting from a first-person perspective with virtual environment events, where avatars or other instrumental intermediaries, such as guns, vehicles, or menu systems, do not to occlude the view. The aesthetic outcomes of this research are the result of combining visual analogies, real time interactive animation, and operatic performance in immersive space. The environments designed in this research were informed initially by paintings created with imagery generated in a hypnopompic state or during the moments of transitioning from sleeping to waking. The drawings often emphasize emotional moments as caricatures and/or elements of the face as seen from a number of perspectives simultaneously, in the way of some cartoons, primitive artwork or Cubist imagery. In the imagery, the faces indicate situations, emotions and confrontations which can offer moments of humour and reflective exploration. At times, the faces usurp the space and stand in representation as both face and figure. The power of the placement of the caricatures in the paintings become apparent as the imagery stages the expressive moment. The placement of faces sets the scene, establishes relationships and promotes the honesty and emotions that develop over time as the paintings are scrutinized. The development process of creating virtual environment imagery starts with hand drawn sketches of characters, develops further as paintings on “digital canvas”, are built as animated, three-dimensional models and finally incorporated into a virtual environment. The imagery is generated while drawing, typically with paper and pencil, in a stream of consciousness during the hypnopompic state. This method became an aesthetic strategy for producing a snappy straightforward sketch. The sketches are explored further as they are worked up as paintings. During the painting process, the figures become fleshed out and their placement on the page, in essence brings them to life. These characters inhabit a world that I explore even further by building them into three dimensional models and placing them in computer generated virtual environments. The methodology of developing and placing the faces/figures became an operational strategy for building virtual environments. In order to open up the range of art virtual environments, and develop operational strategies for visitors’ experience, the characters and their facial features are used as navigational strategies, signposts and methods of wayfinding in order to sustain a stream of consciousness type of navigation. Faces and characters were designed to represent those intimate moments of self-reflection and confrontation that occur daily within ourselves and with others. They sought to reflect moments of wonderment, hurt, curiosity and humour that could subsequently be relinquished for more practical or purposeful endeavours. They were intended to create conditions in which visitors might reflect upon their emotional state, v enabling their understanding and trust of their personal space, in which decisions are made and the nature of world is determined. In order to extend the split-second, frozen moment of recognition that a painting affords, the caricatures and their scenes are given new dimensions as they become characters in a performative virtual reality. Emotables, distinct from avatars, are characters confronting visitors in the virtual environment to engage them in an interactive, stream of consciousness, non-linear dialogue. Visitors are also situated with a role in a virtual world, where they were required to adapt to the language of the environment in order to progress through the dynamics of a drama. The research showed that imagery created in a context of whimsy and fantasy could bring ontological meaning and aesthetic experience into the interactive environment, such that emotables or facially expressive computer graphic characters could be seen as another brushstroke in painting a world of virtual reality.