The Visualization Friday Forum
Fall 2005 * Noon-1pm * D106 LSRC
Sept 9 - Visualization at Duke
Visualization Technology Group
Visualization applies the algorithms of computer graphics with the fields of
and representation to communicate digital information visually. Visualization is used for
presentations, art creation, data analysis, model validation, illustration, data
exploration, entertainment, and cognitive studies.
I'll start the fall term by introducing the Visualization Technology Group and the Friday
Forum series. In particular, I'll fill you in on some of the happenings from over the
summer... such as learning a VR Authoring system for the DiVE (nee Visroom) and talk
about some of the projects planned for that space. CSEM's new quarters on 3rd floor of
North building has opened, and the cluster has been moved to a room with cooling and
Sept 16 - Image and Meaning (2) [PowerPoint Presentation]
Visualization Technology Group
The purpose of the Image and Meaning initiative is to: '...help scientists, writers and visual communicators develop and share improved methods of communicating scientific concepts and technical information through images and visual representations linked to appropriate text. The goal is to enhance the level of discourse within the scientific community, among teachers and those who communicate with the public through the mass media. '
This summer I had the opportunity to participate in IM2 (Image and Meaning 2), the second installment of Image and Meaning. For this Friday forum, I will recap the events from the conference that are of interest to the Duke Visualization community.
Sept 23 - A New Approach to Introductory Programming -
Building Virtual Worlds with Alice [PowerPoint Presentation]
The software tool Alice makes learning to program easy and fun. With Alice
a novice can create a 3D virtual world. This world might be a story, or it
might be an interactive game. Students select 3D objects, place them in a
virtual world, and give these objects functionality. For example, the world
may be a snow scene with a frozen pond, an object may be an ice skater, and
the student teaches the ice skater how to skate, spin and even blink. Alice
cuts down on frustration with its drag-and-drop interface. It is difficult
to make a typing or syntax error. We present the tool Alice and show how
we use it for teaching introductory programming in the course CompSci 4 at
Sept 30 - Quick and Dirty Visualization for Geometric Algorithms [PDF Presentation]
I have been working on several computational geometry algorithms for matching various datasets. The purpose of my research is not to visualize the algorithm, but rather to understand the properties of the algorithms and find improvements. Yet, I felt I still needed a visualizer for several reason: 1) raw numbers from these geometry algorithms are hard to interpret, 2) I want to be able to verify whether the code is correctly implemented, 3) when I try various potential improvements, I want to know immediately whether they work without tedious data analysis. The result is a quick and dirty visualization tool, which was simple to implement, yet served my purposes. As an added benefit, with this tool, it is much easier to explain my work and its contribution.
Oct 7- A Trip in the Virtual Forest –
Building Realistic Forest Domains for Atmospheric Large Eddy Simulations [PowerPoint Presentation]
Turbulence affects the onset, propagation and termination of a diverse array of
biological transport phenomena, such as pathogen spread, biogenic aerosol spread, seed
dispersal, and cloud interaction via biogenic cloud condensation nuclei. It also controls
the exchange of water vapor and CO2 from plant canopies into the atmosphere. Turbulent
eddies occur over a wide range of spatial and temporal scales and are strongly affected
by structural changes in the landscape. Turbulence is chaotic with strong non-linear
interdependence among multiple influential factors. Wind dispersal of seeds, and in
particular long distance dispersal of large seeds, which is a rare event that happens in
the "tail" of the dispersal distribution, can be highly biased by averaging the wind flow-field by using a coarse resolution model. Thus, dispersal processes might not be correctly modeled at a mesoscale resolution. Instead, a spatially explicit high-resolution large eddy simulation (LES) of heterogeneous canopies is needed to study these effects.
These types of LES virtual experiments use computer based high-resolution calculations of air-flow as surrogates for actual wind, which is too hard to experimentally manipulate or measure in detail. But what kind of detailed "virtual canopies" can be used by LES models as simulation domains? Is it possible to measure all the canopy features needed to reproduce a canopy in the virtual domain? And how can all the resulting highly detailed data be viewed?
The virtual canopy generator creates random canopies, with statistical features that are based on features of actual canopies. A step-by-step "virtual canopy" recipe and some preliminary application will be presented.
Oct 14 - The Use of Physiological Reaction in Virtual Environments
Computer Science, UNC
A user’s physiological signals, such as her heart rate and skin
conductance, can provide insight into how she is being affected by a
virtual environment(VE). Common measures of VE effectiveness include the extent to which they
induce a sense of presence (the feeling of being “in” the virtual
scene) or co-presence (the feeling of being with others).One
hypothesis is that the more a VE seems real, the more it evokes
physiological responses similar to those evoked by the corresponding
I’ll present several experiments that have measured physiological
signals during VE sessions, and used them as indicators of presence
and co-presence. I’ll discuss the results of those experiments, as
well as strategies and pitfalls related to the use of physiological
monitoring during VE experiences.
Oct 21 Redirected Walking
Computer Science, UNC
Locomotion in human-scale, immersive virtual environments can be specified by flying with a hand-controller, using a treadmill, walking-in-place, etc. Real walking, where the user actually and physically walks in the lab, and moves the same distance in the virtual scene, is better than flying. It is more input-natural, does not require learning a new interface, results in a greater sense of presence, and theoretically results is less simulator sickness.
With real walking, however, the size of the virtual scene is limited by the size of tracked area. For example, for an architect to really walk in a virtual prototype of a house, the tracked area must be as large as the house. This requirement makes real walking infeasible for many facilities and virtual scenes.
To address this limitation, I have developed Redirected Walking, which makes the user turn herself by interactively and imperceptibly rotating the virtual scene about her. Under the right conditions, the user would unknowingly walk in circles in the lab, thinking she is walking in a straight and arbitrarily long path in the virtual scene.
I'll describe Redirection, discuss its theoretical underpinnings, and argue that it can be used: 1) to make the user turn themselves 2) without causing the user to be aware of Redirection or modify her conscious behavior 3) without unacceptably increasing the level of simulator sickness, most importantly, 4) to useful effect:
A) In head-mounted display systems, the user can experience a virtual scene larger then the lab while also having the benefits of real walking.
B) In an open-backed, three-walled CAVE, users can have the increased presence and input-naturalness normally of a fully enclosed CAVE
I'll finally discuss continuing work on on Redirection to address the lack of haptic feedback (being able to touch and feel virtual objects) in large virtual scenes.
Oct 28 - What can patent landscapes tell us about innovation?
Patents provide an excellent opportunity for studying technological change, but the sheer amount of patent information can easily become overwhelming. How does one classify and analyze such a dataset without imposing biases? If most patents are junk, does that necessarily mean they are noise in our study? What types of conclusions can we draw about the history of a field from a landscape of patent information? I will demonstrate techniques for mapping and exploring patent bibliographic and citation data. I will also discuss pitfalls in analyzing citation maps and describe methods of layering visual data.
Nov 4 -
Surface Parameterization: Flattening the protein-protein interface surface.
I will give a brief overview of various surface parameterization techniques and then focus on flattening the protein-protein interface surface. This surface is a 2-manifold and we need a function that with minimum distortion maps the surface onto a convex polygon in the plane. We have looked at three convex combination mappings and have compared the three using area and angle distortion.
Nov 11 -
Navigating through a Virtual World
Desert Research Institute, Reno, NV
Often virtual reality experiences are designed to mimic the
real world, but sometimes this is not possible or even
desireable. So when not constrained by a lifelike interface
to the world the virtual world designer must consider how
to enable the user to move from place to place. Equally
important, the design must help the user move without getting
lost. In this talk, we'll look at a variety of styles of
travel through virtual reality worlds, along with methods of
keeping the user oriented and heading in the right direction.
Nov 18 - Highlights from the IEEE Visualization conference, and the VR Jam Session
Visualization Technology Group
I will present some of my favorite papers from the IEEE Visualization conference. Just to give you a taste -- one is a very clever way to lay out directed acyclic graphs (i.e. complicated node-link diagrams). Another is a semi-automated process to create textures for showing the shape of imbedded surfaces. These are both very difficult problems. There are several more, both from Information visualization and on the regular visualization side.
I'll also talk about some of the applications that David Zielinski was able to get installed from UIUC and Brown.
Nov 25 - Thanksgiving
Dec 2 - Calm Technology: Designing information with manners
THIS TALK WILL TAKE PLACE IN ROOM 240 OF THE FRANKLIN CENTER.
Wireless devices today require an enormous amount of a very scare resource—our attention. Their interfaces are inscrutable and we continuously apologize for their lack of social etiquette with interruptive ringing, beeping, and buzzing.
Ambient Devices, a spinoff of the MIT Media Lab, is pioneering new way of looking at information which leverages our peripheral senses. We see a future where impolite PCs, PDAs and smart phones won’t be the way we access the Internet. Instead we will populate our living and working spaces with dozens of Ambient objects to keep us attuned to the information we care about most.
Dec 9 -