The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform

Kyudong Park - One of the best experts on this subject based on the ideXlab platform.

  • Usability of the size, spacing, and operation method of virtual buttons with virtual hand on head-mounted displays
    International Journal of Industrial Ergonomics, 2020
    Co-Authors: Kyudong Park
    Abstract:

    Abstract Virtual reality (VR) allows users to see and manipulate virtual scenes and items through input devices, like head-mounted displays. In this study, the effects of button size, spacing, and operation method on the usability of virtual buttons in VR environments were investigated. Task completion time, number of errors, and subjective preferences were collected to test different levels of the button size, spacing, and operation method. The experiment was conducted in a desktop setting with Oculus Rift and Leap motion. A total of 18 subjects performed a button selection task. The optimal levels of button size and spacing within the experimental conditions are 25 mm and between 5 mm and 9 mm, respectively. Button sizes of 15 mm with 1-mm spacing were too small to be used in VR environments. A trend of decreasing task completion time and the number of errors was observed as button size and spacing increased. However, large size and spacing may cause fatigue, due to Continuous Extension of the arms. For operation method, the touch method took a shorter task completion time. However, the push method recorded a smaller number of errors, owing to the visual push-feedback. In this paper, we discuss advantages and disadvantages in detail. The results can be applied to many different application areas with VR HMD using virtual hand interaction.

  • Usability of the Size, Spacing, and Depth of Virtual Buttons on Head-Mounted Displays.
    arXiv: Human-Computer Interaction, 2018
    Co-Authors: Kyudong Park
    Abstract:

    Virtual reality (VR) allows users to see and manipulate virtual scenes and items through input devices, like head-mounted displays. In this study, the effects of button size, spacing, and depth on the usability of virtual buttons in VR environments were investigated. Task completion time, number of errors, and subjective preferences were collected to test different levels of the button size, spacing, and depth. The experiment was conducted in a desktop setting with Oculus Rift and Leap motion. A total of 18 subjects performed a button selection task. The optimal levels of button size and spacing within the experimental conditions are 25 mm and between 5 mm and 9 mm, respectively. Button sizes of 15 mm with 1-mm spacing were too small to be used in VR environments. A trend of decreasing task completion time and the number of errors was observed as button size and spacing increased. However, large size and spacing may cause fatigue, due to Continuous Extension of the arms. For depth effects, the touch method took a shorter task completion time. However, the push method recorded a smaller number of errors, owing to the visual push-feedback. In this paper, we discuss advantages and disadvantages in detail. The results can be applied to many different application areas with VR HMD.

Evgeny Sevost'yanov - One of the best experts on this subject based on the ideXlab platform.

  • On the removal of singularities of the Orlicz–Sobolev classes
    Journal of Mathematical Sciences, 2017
    Co-Authors: Evgeny Sevost'yanov, Ruslan Salimov, Evgenii A. Petrov
    Abstract:

    We study the local behavior of closed-open discrete mappings of the Orlicz–Sobolev classes in ℝ n ; n ≥ 3: It is proved that the indicated mappings have Continuous Extensions to an isolated boundary point x 0 of a domain D/{x 0}, whenever its inner dilatation of order p ∈ (n − 1; n] has FMO (finite mean oscillation) at this point, and, in addition, the limit sets of f at x 0 and on ∂D are disjoint. Another sufficient condition for the possibility of a Continuous Extension can be formulated as a condition of divergence of a certain integral.

  • On the Removability of Isolated Singularities of Orlicz–Sobolev Classes with Branching
    Ukrainian Mathematical Journal, 2016
    Co-Authors: Evgeny Sevost'yanov
    Abstract:

    We study the local behavior of closed-open discrete mappings of the Orlicz–Sobolev classes in $$ {\mathbb{R}}^n $$ , n ≥ 3. It is proved that the indicated mappings have Continuous Extensions to an isolated boundary point x 0 of a domain D \ {x 0}, whenever its inner dilatation has FMO (finite mean oscillation) at this point and, in addition, the limit sets of f at x 0 and on ∂D are disjoint. Another sufficient condition for the possibility of Continuous Extension can be formulated as a condition of divergence of a certain integral.

  • On boundary behavior of mappings of Sobolev and Orlicz--Sobolev class
    arXiv: Complex Variables, 2016
    Co-Authors: Evgeny Sevost'yanov
    Abstract:

    A boundary behavior of closed open discrete mappings of Sobolev and Orlicz--Sobolev classes in ${\Bbb R}^n,$ $n\ge 3,$ is studied. It is proved that, mappings mentioned above have a Continuous Extension to boundary point $x_0$ of a domain $D$ whenever its inner dilatation of order $p$ has a majorant $FMO$ (finite mean oscillation) at the point. Another sufficient condition of possibility of Continuous Extension is a divergence of some integral.

  • On removability of isolated singularities of Orlicz-Sobolev classes with branching
    arXiv: Complex Variables, 2014
    Co-Authors: Evgeny Sevost'yanov
    Abstract:

    A local behavior of closed open discrete mappings of Orlicz--Sobolev classes in ${\Bbb R}^n,$ $n\ge 3,$ is studied. It is proved that, mappings mentioned above have Continuous Extension to isolated boundary point $x_0$ of a domain $D\setminus\{x_0\}$ whenever $n-1$ degree of its inner dilatation has $FMO$ (finite mean oscillation) at the point and, besides that, limit sets of $f$ at $x_0$ and $\partial D$ are disjoint. Another sufficient condition of possibility of Continuous Extension is a divergence of some integral

Atsushi Moriwaki - One of the best experts on this subject based on the ideXlab platform.

  • Continuous Extension of arithmetic volumes
    International Mathematics Research Notices, 2009
    Co-Authors: Atsushi Moriwaki
    Abstract:

    This article is the sequel of the article [4], in which we established the arithmetic volume function of C ∞ -hermitian -invertible sheaves and proved its continuity. The continuity of the volume function has a lot of applications as treated in [4]. In this article, we would like to consider its Continuous Extension over .

  • Continuous Extension of arithmetic volumes
    arXiv: Algebraic Geometry, 2008
    Co-Authors: Atsushi Moriwaki
    Abstract:

    This paper is the sequel of the paper "Continuity of volumes on arithmetic varieties", in which we established the arithmetic volume function of smooth hermitian Q-invertible sheaves and proved its continuity. The continuity of the volume function has a lot of applications as treated in the paper as above. In this paper, we would like to consider its Continuous Extension over R.

Caterina Sartori - One of the best experts on this subject based on the ideXlab platform.

  • CDC - The value function of a finite fuel problem for a new class of singular stochastic controls
    2008 47th IEEE Conference on Decision and Control, 2008
    Co-Authors: Monica Motta, Caterina Sartori
    Abstract:

    We investigate, via the dynamic programming approach, a finite fuel nonlinear singular stochastic control problem of Bolza type. We prove that the associated value function is Continuous and that its Continuous Extension to the closure of the domain coincides with the value function of a non singular control problem, for which we prove the existence of an optimal control. Moreover such a Continuous Extension is characterized as the unique viscosity solution of a quasi variational inequality with suitable boundary conditions of mixed type.

  • Finite Fuel Problem in Nonlinear Singular Stochastic Control
    Siam Journal on Control and Optimization, 2007
    Co-Authors: Monica Motta, Caterina Sartori
    Abstract:

    We investigate, via the dynamic programming approach, a finite fuel nonlinear singular stochastic control problem of Bolza type. We prove that the associated value function is Continuous and that its Continuous Extension to the closure of the domain coincides with the value function of a nonsingular control problem, for which we prove the existence of an optimal control. Moreover, such a Continuous Extension is characterized as the unique viscosity solution of a quasi-variational inequality with suitable boundary conditions of mixed type.

A Messina - One of the best experts on this subject based on the ideXlab platform.

  • the palmar fascia after treatment by the Continuous Extension technique for dupuytren s contracture
    Journal of Hand Surgery (European Volume), 1994
    Co-Authors: G Brandes, A Messina, E Reale
    Abstract:

    Abstract After complete elongation using the Continuous Extension technique the palmar fascia of four patients with Dupuytren's contracture was examined by light and electron microscopy and compared with non-elongated samples from 20 patients at the same clinical stage of the disease. Nodules and cords were no longer clinically recognizable after Extension. The tissue contained collagen fibrils of uniform diameter (about 50 um), densely packed in fibres parallel to the stretching force. Fine filaments (presumably proteoglycans) formed a network which was intermingled with and periodically bound to the collagen fibrils. Fibroblasts and myofibroblasts with an high biosynthetic activity and oxytalan-like microfibrils were aligned along the collagen fibres. The results show that in Dupuytren's disease the contracted palmar fascia reacts to external forces with neoformation and reorientation of all tissue components by myofibroblasts.

  • the tec treatment Continuous Extension technique for severe dupuytren s contracture of the fingers
    Annales De Chirurgie De La Main Et Du Membre Superieur, 1991
    Co-Authors: A Messina, J Messina
    Abstract:

    Summary TEC used for 2 weeks preoperatively has eliminated finger amputation in severe cases of Dupuytren's disease. It must be Continuous to be effective. The apparatus and technique are described.