• Title/Summary/Keyword: exact

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Standardized Protocols for Measuring Volatile Sulfur Compounds: Scientific Foundations and Methodologies

  • Ji-Youn Kim;Ji-Rak Kim;Jin-Seok Byun;Jae-Kwang Jung
    • Journal of Oral Medicine and Pain
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    • v.49 no.1
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    • pp.5-11
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    • 2024
  • Halitosis is defined as a nasty odor emanating through the mouth and is primarily related to the enhanced concentration of volatile sulfur compounds (VSCs). VSC measurements have been commonly used for experimental comparison and clinical diagnosis. As quantitative methods for comparative analyses of oral malodor, gas chromatography devices have been most commonly used to quickly and easily determine the concentration of several gas components of VSCs, which are agents primarily responsible for halitosis. The concentrations of VSCs fluctuate dynamically depending on contributing factors, including various oral/systemic conditions, intake of medicine and food/drink, oral hygiene, and even routine daily activities. Therefore, the exact analysis of VSCs requires the appropriate standardization of not only exact measurement techniques but also participant conditioning with scientific considerations. Thus, this paper describes the experimental standardizations commonly recommended in previous literature and their scientific background.

Exact thermoelastoplastic analysis of FGM rotating hollow disks in a linear elastic-fully plastic condition

  • Nadia Alavi;Mohammad Zamani Nejad;Amin Hadi;Anahita Nikeghbalyan
    • Steel and Composite Structures
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    • v.51 no.4
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    • pp.377-389
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    • 2024
  • In the present study, thermoelsatoplastic stresses and displacement for rotating hollow disks made of functionally graded materials (FGMs) has been investigated. The linear elastic-fully plastic condition is considered. The material properties except Poisson's ratio are assumed to vary in the radial direction as a power-law function. The heat conduction equation for the one-dimensional problem in cylindrical coordinates is used to obtain temperature distribution in the disk. The plastic model is based on the Tresca yield criterion and its associated flow rules under the assumption of perfectly plastic material behavior. Exact solutions of field equations for elastic and plastic deformations are obtained. It is shown that the elastoplastic response of the functionally graded (FG) disk is affected notably by the radial variation of material properties. It is also shown that, depending on material properties and disk dimensions, different modes of plastic deformation may occur.

A STUDY ON REIDEMEISTER OPERATION

  • Lee, Seoung-Ho
    • Bulletin of the Korean Mathematical Society
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    • v.36 no.4
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    • pp.661-669
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    • 1999
  • L. Degui introduced an upper bound of Reidemeister number. In this paper we give a simple proof of Degui's Theorem.

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A NOTE ON PROJECTIVE AND INJECTIBVE AUTOMATA

  • Park, Chin-Hong
    • Journal of applied mathematics & informatics
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    • v.3 no.1
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    • pp.79-88
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    • 1996
  • In this paper we define a new short exact sequence of automata and we investigate module-like properties on projective and injective automata