Biomedical subjects

R Pausch

Publications and source records attributed to R Pausch.

3 recordsLinked to original sources

PubMed1999

Designing a successful HMD-based experience.

For entertainment applications, a successful virtual experience based on a head-mounted display (HMD) needs to overcome some or all of the following problems: entering a virtual world is a jarring experience, people do not naturally turn their heads or talk to each other while wearing an HMD, putting on the equipment is hard, and people do not realize when the experience is over. In the Electric Garden at SIGGRAPH 97, we presented the Mad Hatter's Tea Party, a shared virtual environment experienced by more than 1,500 SIGGRAPH attendees. We addressed these HMD-related problems with a combination of back story, see-through HMDs, virtual characters, continuity of real and virtual objects, and the layout of the physical and virtual environments.

Computer Graphics↗

PubMed1997

The props-based interface for neurosurgical visualization.

We describe a three-dimensional human-computer interface for neurosurgical visualization. The interface is based on the two-handed physical manipulation of hand-held tools, or "props", in free space. These user interface "props" facilitate transfer of the user's skills for manipulating tools with two hands to the operation of a user interface for visualizing 3D medical images, without need for training. The interface allows neurosurgeons to explore a 3D MRI scan of a patient's brain during presurgical planning. From the surgeon's perspective, the interface is analogous to holding a miniature head in one hand which can be "sliced open" or "pointed to" using a cross-sectioning plane or a stylus tool, respectively, held in the other hand. Cross-sectioning a 3D volume, for example, simply requires the surgeon to hold a plastic plate (held in the preferred hand) up to the miniature head (held in the nonpreferred hand) to demonstrate the desired cross-section.

Computer Simulation↗

PubMed1996

Effects of enhanced O3 and CO2 enrichment on plant characteristics in wheat and corn.

The effects of CO(2) enrichment and O(3) induced stress on wheat (Triticum aestivum L.) and corn (Zea mays L.) were studied in field experiments using open-top chambers to simulate the atmospheric concentrations of these two gases that are predicted to occur during the coming century. The experiments were conducted at Beltsville, MD, during 1991 (wheat and corn) and 1992 (wheat). Crops were grown under charcoal filtered (CF) air or ambient air + 40 nl liter(-1) O(3) (7 h per day, 5 days per week) having ambient CO(2) concentration (350 microl liter(-1) CO(2)) or + 150 microl liter(-1) CO(2) (12 h per day.). Averaged over O(3) treatments, the CO(2)-enriched environment had a positive effect on wheat grain yield (26% in 1991 and 15% in 1992) and dry biomass (15% in 1991 and 9% in 1992). Averaged over CO(2) treatments, high O(3) exposure had a negative impact on wheat grain yield (-15% in 1991 and -11% in 1992) and dry biomass (-11% in 1991 and -9% in 1992). Averaged over CO(2) treatments, high O(3) exposure decreased corn grain yield by 9%. No significant interactive effects were observed for either crop. The results indicated that CO(2) enrichment had a beneficial effect in wheat (C(3) crop) but not in corn (C(4) crop). It is likely that the O(3)-induced stress will be diminished under increased atmospheric CO(2) concentrations; however, maximal benefits in crop production in wheat in response to CO(2) enrichment will not be materialized under concomitant increases in tropospheric O(3) concentration.

Journal Article↗