• 베이커리
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• no.5 s.322
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• pp.154-161
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• 1995

• The Korean Journal of Rheology
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• v.1 no.1
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• pp.71-79
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• 1989

임계연신비로 특징지어지는 비등온 방사공정에서의 Draw Resonance 발생을, White 의 변형속도에 따라 변하는 물질의 이완시간 모델에 의한 convected Maxwell 유체의 방사 모형을 사용해서 연구했다. 임계연신비의 계산에는 다른 연구자들이 이용하는 통상의 복잡 한 수치계산인 eigenvalue 방법을 쓰지 않고 전파하는 동적 waves 에 근거한 간단한 Hyun 의 이론을 사용했다. 그 결과 Staton Number와 냉각 공기온도로서 나타내지는 방사공정의 냉각이 공정을 안정시킨다는 것이 밝혀졌다. 다시 말해서 연신점도가 변형후화인 유체이거 나 변형박화인 유체이거난 상관없이 항상 Stanton Number가 켜지거나 또는 냉각공기온도 가 낮아질수록(즉냉각효과가 커질 때) 임계연신비가 커지는 것이다(단변형박화 dvcp의 빌부 구간을 제외하고) 한편 Draw Resonacnce 에 미치는 냉각의 효과는 무차원 이완시간(a Weissenberg Number 혹은 a Deborah number)이 커질수록 작아진다는 것도 발견됐다. 이 것은 process Time 이 작아지면 열전달이 작아지기 때문이다. 이러한 내용들은 다른 연구 자들의 결과와도 잘 부합된다.

• Pediatric Infection and Vaccine
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• v.6 no.1
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• pp.93-100
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• 1999

Purpose : For evaluation of acute Mycoplasma pneumoniae(M. pneumoniae) pneumonia in children, we have studied the Mycoplasma indirect particle agglutination test, cold hemagglutinin test, ESR, CRP, and total white blood cell counts and it's differential count retrospectively. Methods : The total numbers of patients whom compatible with diagnostic criteria of acute M. pneumoniae peumonia were 56 cases from Jan. to Dec. 1997. The diagnostic criteria were 1) onset of fever(${\geq}38.0^{\circ}C$) and coughing were within 7 days, 2) rhonchi and/or role was audible on chest, 3) pneumonic infiltration on chest X-ray, and 4) M. pneumoniae indirect particle agglutination test titer was higher than 1:640, or initial titer was less than 1:640 but increased more than 4 folds after week. We classified the enrolled patients according to initial antibody titer, such as soup A(${\leq}1:640$) and group B(${\geq}1:320$). We compared group A and B by demographic findings, clinical symptoms and signs, and laboratory findings. Results : 1) The male and female sex ratio was 1:1.4, and average onset age was $5.8{\pm}2.96$ years. 2) The average body temperature on admission was $38.5{\pm}0.1^{\circ}C$ and productive coughing was noticed in 52 cases(93%). 3) The average total white cell counts were $10,470{\pm}877.0/mm^3$ in group B patients, which was significantly higher compared to $7,761{\pm}508.5/mm^3$ in group A(p<0.014). 4) The average value of ESR and CRP were within normal range in both group. 5) The most common site of pneumonic infiltration was right lower lobe of lung in both groups. 6) There were no correlation between antibody titer and cold hemagglutinine titer in patients and cold hemagglutination titer were less than 1:64 in 25 cases(45%). Conclusion : The clinical manifestations of pneumonia, findings of chest x-ray, and indirect particle agglutination test were useful on diagnosis of M. pneumoniae pnumonia onset within 7 days, but cold hemagglutinin test was a little diagnostic meaning.