• Publications
  • Influence
Measuring Presence in Virtual Environments: A Presence Questionnaire
The effectiveness of virtual environments (VEs) has often been linked to the sense of presence reported by users of those VEs. Expand
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The Factor Structure of the Presence Questionnaire
Constructing a valid measure of presence and discovering the factors that contribute to presence have been much sought after goals of presence researchers. Expand
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Critical Evaluation of the Use of Laser Diffraction for Particle-Size Distribution Analysis
Determination of soil particle-size distribution (PSD) by sieving, hydrometer, and pipette methods as well as by laser diffraction (LD) suffers from inherent flaws, mainly due to the difficulty inExpand
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Soils, an introduction
1. Introduction. Soil. What Is Soil? How Do Soils Form? Minerals and Organic Matter. Size and Organization of Particles. Soil Pores. Surface Reactions and Transfer Processses. Soil as an Ecosystem.Expand
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Simulation Fidelity in Training System Design: Bridging the Gap Between Reality and Training
I: Simulation Fidelity: Definitions, Problems, and Historical Perspectives.- 1: Definitions and Problems in Training System Design.- Rationale for use of training devices.- Current training systemExpand
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Soil compaction effects on growth of young ponderosa pine following litter removal in California's Sierra Nevada
Increased use of heavy equipment and more frequent entry into forest stands has increased the potential for soil compaction and decreased productivity. We examined compaction and tree growthExpand
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Oak tree and grazing impacts on soil properties and nutrients in a California oak woodland
There is great interest in understandinghow rangeland management practices affectthe long-term sustainability of California oakwoodland ecosystems through their influence onnutrient cycling. ThisExpand
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Pedogenesis and paleoclimate: Interpretation of the magnetic susceptibility record of Chinese loess-paleosol sequences
In the Chinese loess-paleosol sequences from Luochuan, Haanxi province, China, variations in the magnetic susceptibility have been accepted as an excellent proxy for paleoclimate, and the standardExpand
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Amplification of the human dihydrofolate reductase gene via double minutes is initiated by chromosome breaks.
DNA sequence amplification is one of the most frequent manifestations of genomic instability in human tumors. We have shown previously that amplification of the dihydrofolate reductase (DHFR) gene inExpand
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Distance Estimation in Virtual Environments
This paper describes an experiment to evaluate a procedure for measuring distance perception in immersive VEs. Forty-eight subjects viewed a VE with a Head Mounted Display (HMD), a BinocularExpand
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