• 제목/요약/키워드: admissible

검색결과 342건 처리시간 0.024초

상계해석법을 이용한 평면변형 열간 판압연공정해석 (Upper Bound Analysis of Plane Strain Hot Strip Rolling Process)

  • 문영훈;천명식;이준성
    • 대한기계학회논문집A
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    • 제20권8호
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    • pp.2468-2479
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    • 1996

  • An upper bound solution is obtained to perform the process analysis of hot strip rolling process. The material flows within the roll bite at various geometries and frictional conditions are obtained from finite element analysis and the typical flow pattern which is necessary to determine the kinematically admissible velocity field is assumed. From the kinematically admissible velocity field, the upper bound energy is calculated and the rolling load, angle of neutral point and forward slip ratio at various operational conditions are obtained from upper bound energy. The process analysis of above mentioned parameters at various operational conditions have provided valuable information which is hard to obtain during rolling operation and the predicted ranges of quantitive values from these analyses lie whthin the bound of actual operational data.

  • https://doi.org/10.22634/KSME-A.1996.20.8.2468 인용 PDF

Recovery of Asteroids from Observations of Too-Short Arcs by Triangulating Their Admissible Regions

  • Espitia, Daniela;Quintero, Edwin A.;Parra, Miguel A.
    • Journal of Astronomy and Space Sciences
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    • 제38권2호
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    • pp.119-134
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    • 2021

  • The data set collected during the night of the discovery of a minor body constitutes a too-short arc (TSA), resulting in failure of the differential correction procedure. This makes it necessary to recover the object during subsequent nights to gather more observations that will allow a preliminary orbit to be calculated. In this work, we present a recovery technique based on sampling the admissible region (AdRe) by the constrained Delaunay triangulation. We construct the AdRe in its topocentric and geocentric variants, using logarithmic and exponential metrics, for the following near-Earth-asteroids: (3122) Florence, (3200) Phaethon, 2003 GW, (1864) Daedalus, 2003 BH84 and 1977 QQ5; and the main-belt asteroids: (1738) Oosterhoff, (4690) Strasbourg, (555) Norma, 2006 SO375, 2003 GE55 and (32811) Apisaon. Using our sampling technique, we established the ephemeris region for these objects, using intervals of observation from 25 minutes up to 2 hours, with propagation times from 1 up to 47 days. All these objects were recoverable in a field of vision of 95' × 72', except for (3122) Florence and (3200) Phaethon, since they were observed during their closest approach to the Earth. In the case of 2006 SO375, we performed an additional test with only two observations separated by 2 minutes, achieving a recovery of up to 28 days after its discovery, which demonstrates the potential of our technique.

  • https://doi.org/10.5140/JASS.2021.38.2.119 인용 PDF KSCI