• Title/Summary/Keyword: 눌림 현상

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A Survey of Human Injury and Crowd Packing in Mass Gathering (군중집회 시의 인명피해 및 군중눌림 현상의 고찰)

  • Wang, Soon-Joo;Byun, Hyun-Joo
    • Journal of the Society of Disaster Information
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    • v.7 no.1
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    • pp.12-20
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    • 2011
  • This study was performed for identifying the characteristics of mass gathering and human injury in mass gathering based on the literature survey and analysis of mass gathering and crowd packing. The size and density of crowd influenced the characteristics of mass gathering according to type of mass gathering. The variables and causes of human injuries of mass gathering have positive or negative influences based on the weather, attendance, duration, location, mobility, event type, crowd mood, alcohol, drug, crowd density and age. Based on the physical mechanism of crowd packing, the degree of crowd packing was influenced by crowd pressure, crowd density and lasting time. But the magnitude of pressure for pedestrian injury criteria remains for further research.

Morpholgical Characteristics of Hair Section According to Cutting Tools (커트 도구에 따른 모발 절단면의 형태학적 특성)

  • Lee, Gui-Young;Roh, Jung-Ae;Chang, Byung-Soo
    • Applied Microscopy
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    • v.38 no.4
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    • pp.347-351
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    • 2008
  • The morphological characteristics of the cut sections of hair using razor, clipper and scissors were investigated with scanning electron microscopy. With the razor, the cutting section had a long elliptical form and a rhythmical ribbon shape. It was curved outward since the end part of it became thinner. With the scissors, the cutting section had a flat, circular form. It seemed to be because the scissors imposed a constant strength on the hair. With the clipper, the cutting section had also a circular form but a layer of the macrofibril was generated in the middle part of the cortex. It seemed to be generated while the rapidly moving blades of the clipper cut the hair in an instant.

Manufacture of Crack-free Carbonized Board from Fiberboard (섬유판을 이용한 무할렬 탄화보드 제조)

  • Park, Sang-Bum;Lee, Sang-Min;Park, Jong-Young;Lee, Seon-Hwa
    • Journal of the Korean Wood Science and Technology
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    • v.37 no.4
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    • pp.293-299
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    • 2009
  • In manufacturing the crack-free carbonized boards using fiberboards, shrinking ratio, weight loss and density variation of carbonized boards at each carbonization temperature were investigated. Fiberboards with thickness of 3, 4.5, 6, and 18 mm were carbonized while pressed with pressure plates at different temperature from $400^{\circ}C$ to $1,000^{\circ}C$ using a ordinary laboratory furnace. Either of crack or twist was not observed in fiberboards by adapting the pressing carbonization method. The ratios of shrinkage of length, width, and thickness were 10~25%, 12~25%, and 28~48%, respectively, and shrinkage ratio of thickness was higher than those of length and width with increasing the carbonization temperature. Weight loss tended to increase with increasing the carbonization temperature, but low correlation between weight loss in thickness of fiberboards and carbonization temperature was observed. Density of 3 mm carbonized hardboard had the highest value and it tended to increase with increasing the carbonization temperature.

Fossil Scaphopods from the Hagjeon Formation and the Duho Formation, the Cenozoic Pohang Basin, Korea (신생대 제3기 포항분지의 학전층과 두호층에서 산출된 굴족류 화석)

  • Kong, Dal Yong;Lee, Seong Joo
    • Korean Journal of Heritage: History & Science
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    • v.45 no.1
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    • pp.218-231
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    • 2012
  • A total of 126 fossil scaphopods (121 specimens from the Hagjeon Formation and 5 specimens from the Duho Formation) were found from the Cenozoic strata, Hagjeon and Duho Formations, Pohang Basin, Korea. Five species belonging two genera (Fissidentalium yokoyamai, F. sp. A, B, and Rhabdus sp. A, B) were classified: the most dominant species is Fissidentalium yokoyamai. The species of Fissidentalium yokoyamai is characterized by curved shell (accuration=3.90%) and very closely spaced longitudinal ribs on shell surfaces, while the species of Rhabdus is a nearly straight shell characterized by concentric growth lines without longitudinal ribs. Identification of two genera is somewhat easy due to such morphological differences but classification at generic level is hard because diagnostic features (e.g., cross section and apical structure) are lost in the most specimens. Consequently, except for Fissidentalium yokoyamai, the rest were classified temporarily as F. sp. A, B, and Rhabdus sp. A, B. Two types of preservation state were recognized: one is three-dimensionally preserved specimen (3D specimen) and the other is compressed specimen. Internal parts of the 3D specimen is filled with clastic sediments identical to the surrounding sediments of the shells, which is not observed in the compressed specimens. It is, thus, concluded that the 3D fossils were originally empty but internal cavity were immediately filled with the sediments, which may have protect from the compaction due to pressure during deposition of the gravelly to coarse sandstone of the Hagjeon Formation.