The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Jogender Singh - One of the best experts on this subject based on the ideXlab platform.
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a novel laser liquid solid Interaction Technique for synthesis of silver nickel and immiscible silver nickel alloys from liquid precursors
Journal of Materials Science, 2000Co-Authors: Deepak Poondi, Tabbetha Dobbins, Jogender SinghAbstract:Silver, nickel, nickel oxide and silver-nickel alloys have been produced from their inexpensive liquid precursors using CO2 and Nd-YAG lasers. Ethylene glycol, diethylene glycol and 2-ethoxyethanol were used as reductants in the synthesis reactions. Spherical and faceted silver particles of high purity were formed by laser Interaction between the precursor solution and a rotating substrate, while porous dual phase nickel and nickel oxide particles were produced when nickel nitrate was used as a precursor. The composition and morphology of the alloy particles was dependent on laser parameters and chemical composition of the precursor solution. The product composition was dependent only upon the chemistry of the precursors used. The mean particle size was dependent upon the temperature generated by irradition and the duration of exposure to the laser beam. The synthesis of nano-particles and metastable alloys is proposed to occur primarily at the laser-liquid-solid interface by a nucleation and growth mechanism.
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synthesis of metastable silver nickel alloys by a novel laser liquid solid Interaction Technique
Journal of Materials Science, 2000Co-Authors: Deepak Poondi, Jogender SinghAbstract:Metastable silver-nickel alloys have been synthesized by chemical wetness and laser-liquid-solid Interaction Techniques from nitrate and acetate precursors of silver and nickel. Ethylene glycol and 2-ethoxyethanol were used as reductants in the synthesis reactions. Rotating niobium substrates immersed in the liquid precursor were irradiated by a continuos wave CO2 and Nd-YAG laser (λ = 1064 nm). The powders were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and high-resolution transmission electron microscopy (HRTEM). Two-phase alloys containing silver, nickel, and oxygen were fabricated, and the shape of the particles was found to be dependent on laser parameters and the chemical composition of the precursor solution. The synthesis mechanism of non-equilibrium Ag-Ni alloy nanoparticles has been proposed to occur primarily at the laser-liquid-solid interface by a nucleation and growth mechanism.
Deepak Poondi - One of the best experts on this subject based on the ideXlab platform.
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a novel laser liquid solid Interaction Technique for synthesis of silver nickel and immiscible silver nickel alloys from liquid precursors
Journal of Materials Science, 2000Co-Authors: Deepak Poondi, Tabbetha Dobbins, Jogender SinghAbstract:Silver, nickel, nickel oxide and silver-nickel alloys have been produced from their inexpensive liquid precursors using CO2 and Nd-YAG lasers. Ethylene glycol, diethylene glycol and 2-ethoxyethanol were used as reductants in the synthesis reactions. Spherical and faceted silver particles of high purity were formed by laser Interaction between the precursor solution and a rotating substrate, while porous dual phase nickel and nickel oxide particles were produced when nickel nitrate was used as a precursor. The composition and morphology of the alloy particles was dependent on laser parameters and chemical composition of the precursor solution. The product composition was dependent only upon the chemistry of the precursors used. The mean particle size was dependent upon the temperature generated by irradition and the duration of exposure to the laser beam. The synthesis of nano-particles and metastable alloys is proposed to occur primarily at the laser-liquid-solid interface by a nucleation and growth mechanism.
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synthesis of metastable silver nickel alloys by a novel laser liquid solid Interaction Technique
Journal of Materials Science, 2000Co-Authors: Deepak Poondi, Jogender SinghAbstract:Metastable silver-nickel alloys have been synthesized by chemical wetness and laser-liquid-solid Interaction Techniques from nitrate and acetate precursors of silver and nickel. Ethylene glycol and 2-ethoxyethanol were used as reductants in the synthesis reactions. Rotating niobium substrates immersed in the liquid precursor were irradiated by a continuos wave CO2 and Nd-YAG laser (λ = 1064 nm). The powders were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and high-resolution transmission electron microscopy (HRTEM). Two-phase alloys containing silver, nickel, and oxygen were fabricated, and the shape of the particles was found to be dependent on laser parameters and the chemical composition of the precursor solution. The synthesis mechanism of non-equilibrium Ag-Ni alloy nanoparticles has been proposed to occur primarily at the laser-liquid-solid interface by a nucleation and growth mechanism.
Regis Kopper - One of the best experts on this subject based on the ideXlab platform.
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6 degrees of freedom manipulation with a transparent tangible object in world fixed virtual reality displays
IEEE Virtual Reality Conference, 2017Co-Authors: David J Zielinski, Derek Nankivil, Regis KopperAbstract:We propose Specimen Box, an Interaction Technique that allows world-fixed display (such as CAVEs) users to naturally hold a plausible physical object while manipulating virtual content inside it. This virtual content is rendered based on the tracked position of the box. Specimen Box provides the weight and tactile feel of an actual object and does not occlude rendered objects in the scene. The end result is that the user sees the virtual content as if it exists inside the clear physical box. We conducted a user study which involved a cognitively loaded inspection task requiring extensive manipulation of the box. We compared Specimen Box to Grab-and-Twirl, a naturalistic bimanual manipulation Technique that closely mimics the mechanics of our proposed Technique. Results show that performance was significantly faster with Specimen Box. Further, performance of the control Technique was positively affected by experience with Specimen Box.
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specimen box a tangible Interaction Technique for world fixed virtual reality displays
Symposium on 3D User Interfaces, 2017Co-Authors: David J Zielinski, Derek Nankivil, Regis KopperAbstract:Object selection and manipulation in world-fixed displays such as CAVE-type systems are typically achieved with tracked input devices, which lack the tangibility of real-world Interactions. Conversely, due to the visual blockage of the real world, head-mounted displays allow the use of many types of real world objects that can convey realistic haptic feedback. To bridge this gap, we propose Specimen Box, an Interaction Technique that allows users to naturally hold a plausible physical object while manipulating virtual content inside it. This virtual content is rendered based on the tracked position of the box in relation to the user's point of view. Specimen Box provides the weight and tactile feel of an actual object and does not occlude rendered objects in the scene. The end result is that the user sees the virtual content as if it exists inside the clear physical box. We hypothesize that the effect of holding a physical box, which is a valid part of the overall scenario, would improve user performance and experience. To verify this hypothesis, we conducted a user study which involved a cognitively loaded inspection task requiring extensive manipulation of the box. We compared Specimen Box to Grab-and-Twirl, a naturalistic bimanual manipulation Technique that closely mimics the mechanics of our proposed Technique. Results show that in our specific task, performance was significantly faster and rotation rate was significantly lower with Specimen Box. Further, performance of the control Technique was positively affected by experience with Specimen Box.
Doug A Bowman - One of the best experts on this subject based on the ideXlab platform.
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volume cracker a bimanual 3d Interaction Technique for analysis of raw volumetric data
Symposium on Spatial User Interaction, 2013Co-Authors: Bireswar Laha, Doug A BowmanAbstract:Analysis of volume datasets often involves peering inside the volume to understand internal structures. Traditional approaches involve removing part of the volume through slicing, but this can result in the loss of context. Focus+context visualization Techniques can distort part of the volume, or can assume prior definition of a region of interest or segmentation of layers of the volume. We propose a new bimanual 3D Interaction Technique, called Volume Cracker (VC), which allows the user to crack open a raw volume like a book to analyze the internal structures. VC preserves context by always displaying all the voxels, and by connecting the sub-volumes with curves joining the cracked faces. We discuss the design choices that we made, based on observations from prior user studies, input from domain scientists, and design studios. We also report the results of a user study comparing VC with a standard desktop Interaction Technique and a standard 3D bimanual Interaction Technique. The study used tasks from two categories of a generic volume analysis task taxonomy. We found VC had significant advantages over the other two Techniques for search and pattern recognition tasks.
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Poster: Volume Cracker: A bimanual 3D Interaction Technique for analysis of raw volumetric data
2013 IEEE Symposium on 3D User Interfaces (3DUI), 2013Co-Authors: Bireswar Laha, Doug A BowmanAbstract:Volume data analysis often involves finding structures inside the volume. Segmentation is the standard method, but it is quite time-consuming. Alternate approaches remove context, assume prior definition of ROI or segments, or distort part of the volume. We propose a new bimanual 3D Interaction Technique, called Volume Cracker (VC), which allows the user to crack open a volume like a book to analyze the internal structures. VC preserves context by always displaying all the voxels, and by connecting the sub-volumes with curves joining the cracked faces. We discuss the various design choices that we made, based on observations from our prior user studies with volume datasets, inputs from domain scientists, and numerous design studios and brainstorming sessions. We also report the results of a user study comparing VC with a standard desktop Interaction Technique and a standard 3D bimanual Interaction Technique. The study used tasks from two categories of a volume analysis task taxonomy that we are designing in consultation with domain scientists. We found VC had significant advantages over the other two Techniques for search and pattern recognition tasks.
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a multiscale Interaction Technique for large high resolution displays
Symposium on 3D User Interfaces, 2009Co-Authors: Sarah M Peck, Chris North, Doug A BowmanAbstract:This paper explores the link between users' physical navigation, specifically their distance from their current object(s) of focus, and their Interaction scale. We define a new 3D Interaction Technique, called multiscale Interaction, which links users' scale of perception and their scale of Interaction. The Technique exploits users' physical navigation in the 3D space in front of a large high-resolution display, using it to explicitly control scale of Interaction, in addition to scale of perception. Other Interaction Techniques for large displays have not previously considered physical navigation to this degree. We identify the design space of the Technique, which other researchers can continue to explore and build on, and evaluate one implementation of multiscale Interaction to begin to quantify the benefits of the Technique. We show evidence of a natural psychological link between scale of perception and scale of Interaction and that exploiting it as an explicit control in the user interface can be beneficial to users in problem solving tasks. In addition, we show that designing against this philosophy can be detrimental.
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separating the effects of level of immersion and 3d Interaction Techniques
Virtual Reality Software and Technology, 2006Co-Authors: Ryan P Mcmahan, Doug Gorton, Joe Gresock, Will Mcconnell, Doug A BowmanAbstract:Empirical evidence of the benefits of immersion is an important goal for the virtual environment (VE) community. Direct comparison of immersive systems and non-immersive systems is insufficient because differences between such systems may be due not only to the level of immersion, but also to other factors, such as the input devices and Interaction Techniques used. In this paper, a study is presented that separates the effects of level of immersion and 3D Interaction Technique for a six-degree-of-freedom manipulation task. In the study, two components of immersion -- stereoscopy and field of regard -- were varied and three 3D Interaction Techniques -- HOMER, Go-Go, and DO-IT (a new keyboard- and mouse-based Technique) -- were tested. The results of the experiment show that the Interaction Technique had a significant effect on object manipulation time, while the two components of immersion did not. The implications of these results are discussed for VE application developers.
David J Zielinski - One of the best experts on this subject based on the ideXlab platform.
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6 degrees of freedom manipulation with a transparent tangible object in world fixed virtual reality displays
IEEE Virtual Reality Conference, 2017Co-Authors: David J Zielinski, Derek Nankivil, Regis KopperAbstract:We propose Specimen Box, an Interaction Technique that allows world-fixed display (such as CAVEs) users to naturally hold a plausible physical object while manipulating virtual content inside it. This virtual content is rendered based on the tracked position of the box. Specimen Box provides the weight and tactile feel of an actual object and does not occlude rendered objects in the scene. The end result is that the user sees the virtual content as if it exists inside the clear physical box. We conducted a user study which involved a cognitively loaded inspection task requiring extensive manipulation of the box. We compared Specimen Box to Grab-and-Twirl, a naturalistic bimanual manipulation Technique that closely mimics the mechanics of our proposed Technique. Results show that performance was significantly faster with Specimen Box. Further, performance of the control Technique was positively affected by experience with Specimen Box.
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specimen box a tangible Interaction Technique for world fixed virtual reality displays
Symposium on 3D User Interfaces, 2017Co-Authors: David J Zielinski, Derek Nankivil, Regis KopperAbstract:Object selection and manipulation in world-fixed displays such as CAVE-type systems are typically achieved with tracked input devices, which lack the tangibility of real-world Interactions. Conversely, due to the visual blockage of the real world, head-mounted displays allow the use of many types of real world objects that can convey realistic haptic feedback. To bridge this gap, we propose Specimen Box, an Interaction Technique that allows users to naturally hold a plausible physical object while manipulating virtual content inside it. This virtual content is rendered based on the tracked position of the box in relation to the user's point of view. Specimen Box provides the weight and tactile feel of an actual object and does not occlude rendered objects in the scene. The end result is that the user sees the virtual content as if it exists inside the clear physical box. We hypothesize that the effect of holding a physical box, which is a valid part of the overall scenario, would improve user performance and experience. To verify this hypothesis, we conducted a user study which involved a cognitively loaded inspection task requiring extensive manipulation of the box. We compared Specimen Box to Grab-and-Twirl, a naturalistic bimanual manipulation Technique that closely mimics the mechanics of our proposed Technique. Results show that in our specific task, performance was significantly faster and rotation rate was significantly lower with Specimen Box. Further, performance of the control Technique was positively affected by experience with Specimen Box.