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In this paper, we investigate the effects of the physical influence of a virtual human (VH) in the context of face-to-face interaction in augmented reality (AR). In our study, participants played a tabletop game with a VH, in which each player takes a turn and moves their own token along the designated spots on the shared table. We compared two conditions as follows: the VH in the virtual condition moves a virtual token that can only be seen through AR glasses, while the VH in the physical condition moves a physical token as the participants do; therefore the VH’s token can be seen even in the periphery of the AR glasses. For the physical condition, we designed an actuator system underneath the table. The actuator moves a magnet under the table which then moves the VH’s physical token over the surface of the table. Our results indicate that participants felt higher co-presence with the VH in the physical condition, and participants assessed the VH as a more physical entity compared to the VH in the virtual condition. We further observed transference effects when participants attributed the VH’s ability to move physical objects to other elements in the real world. Also, the VH’s physical influence improved participants’ overall experience with the VH. We discuss potential explanations for the findings and implications for future shared AR tabletop setups.
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A random variant of the game of plates and olives
The game of plates and olives was originally formulated by Nicolaescu and encodes the evolution of the topology of the sublevel sets of Morse functions. We consider a random variant of this game. The process starts with an empty table. There are four different types of moves: (1) add a new plate to the table, (2) combine two plates and their olives onto one plate, removing the second plate from the table, (3) add an olive to a plate, and (4) remove an olive from a plate. We show that with high probability the number of olives is linear as the total number of moves goes to infinity. Furthermore, we prove that the number of olives is concentrated around its expectation.
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- Award ID(s):
- 1661063
- PAR ID:
- 10157628
- Date Published:
- Journal Name:
- SIAM journal on discrete mathematics
- Volume:
- 33
- Issue:
- 2019
- ISSN:
- 0895-4801
- Page Range / eLocation ID:
- 1216-1227
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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