• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2696-2698
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• 2000

본 연구에서는 실수형 염색체들로 구성된 개체에 대해 감수분열을 적용하여 개체를 만들고, 이 생식체들의 랜덤한 선택과 교배에 의해 세대가 진화함에 따라 탐색을 수행하는 감수분열 유전알고리즘을 이용하여 퍼지모델의 최적 구조와 파라미터를 탐색하고 Gradient Descent 알고리즘으로 파라미터를 정밀 조정하는 방안을 제안한다. 제안된 방안을 적용하여 Box-Jenkins의 가스로 데이터에 대한 퍼지모델을 구성하고 그 적용 가능성을 보인다.

• Journal of Plant Biology
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• v.34 no.2
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• pp.137-144
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• 1991

기주식물 (토끼풀, Trifolium repens L.)에 기생하는 실새삼(Cuscuta australis R. Brown)의 흡기내 목부의 개체발생 과정을 광학현미경으로 조사하였다. 흡기의 목부 분화를 암시하는 최초의 해부학적 특징이, 흡기 자체내에서가 아니라, 그 흡기가 형성되어 있는 실새삼 줄기에서 나타났다. 즉 실새삼 줄기의 중심주의 유관속 내부 및 유관속 사이에서 세포분열 활성이 관찰되었다. 이 분열로부터 유도된 세포들은 짙게 염색된 세포질과 뚜렷한 핵을 갖고 있었다. 흡기가 기주조직에 침입하여 생장함에 따라, 실새삼 줄기의 중심주에서 시작된 세포분열 활성은 유관속 사이를 거쳐서 흡기의 기부를 향하여 구정적으로 확장되었다. 이와 동시에, 실새삼 줄기의 목부에 인접해 있던, 짙은 세포질 밀도를 갖는 세포들이 목부요소로 분화하기 시작하였다. 결국, 이미 형성되었던 짙게 염색된 세포들을 따라서 흡기의 목부는 구정적으로 분화하였다. 실새삼 줄기의 중심주에서 일어나는 유조직 세포들의 분열활성 및 이로부터 흡기의 목부 분화를 구정적으로 유도할 수 있는 가능성에 대하여 논의하였다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.131-134
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• 2007

This numerical analysis was performed in order to validate adoption of the sheet breakup model in high-pressure environment, which were used for prediction of spray characteristics in atmosphere environment. In experiments the higher environment pressure the shorter breakup length; the results of new sheet breakup model predicted the breakup length in good agreement with experimental results qualitatively and quantitatively. Also the shape of spray calculated by numerical analysis were agreed well with experiments quantitatively.

• Journal of ILASS-Korea
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• v.9 no.4
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• pp.1-8
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• 2004

Breakup characteristics of liquid sheets formed by the impingement of two water jets, such as a breakup length and a breakup wavelength of sheet, were investigated as increasing the injection velocity up to 30m/s and the ambient gas pressure up to 4.0MPa. While round edged orifices formed a laminar sheet which has no waves on the sheet when the injection velocity is low, sharp edged orifices formed a turbulent sheet which has impact waves irrespective of the injection velocity. Thus we compared the differences of breakup characteristics between them. The results showed that the aerodynamic force significantly affects the breakup of laminar sheet when the gas based Weber number is higher than unity, It was also found that the turbulent sheets have three breakup regimes, i.e. expansion regime, wave breakup regime and catastrophic breakup regime according to the gas based Weber number.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1998.04a
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• pp.16-16
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• 1998

로켓의 추진제에는 고체 추진제와 액체 추진제를 사용하는 두 경우로 나눌 수 있는데, 액체 추진제를 사용하는 경우, 액체 연료와 액체 산화제를 다양한 방법으로 연소실내로 분사하게 된다. 이때 사용되는 injector들 중에 impingement type이 있다. 이 type은 injector의 가공이 비교적 용이하고, 혼합성능이 좋기 때문에 LOX/RP-1(Kerosin-based hydrocarbon fuel)을 사용하는 액체 로켓엔진에서 주로 사용되어 왔다. 두 액체 jet의 충돌에 의해 액막이 형성되는데, 이 액막은 가장자리로 갈수록 두께가 얇아지며 액막표면의 파는 충돌점으로부터 멀어질수록 그 진폭의 증가를 이루어 액체의 표면장력과 관성력의 균형을 깨트리며, 이 순간 액막은 rim의 형태로 분열하여 결국에는 액적을 생성하게 된다. 현재까지의 연구내용은 충돌 jet의 형태 laminar jet과 turbulent jet으로 구분된 인젝트에 관해 연구되어왔고, 특히 국내에는 이러한 구분된 충돌 jet의 분열현상에 관한 연구결과가 미흡하다. 동일한 오르피스의 경우에도 laminar jet과 turbulent jet으로 구분되어 지며, 각각의 jet의 형태에 따라 생성되는 액막의 형상 또는 다르게 생성되어 진다. 그러므로 본 연구에서는 두 구분된 jet의 경우의 분열현상을 실험적으로 분석하였다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.171-174
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• 2008

This paper presents disintegration process of the small rotational fuel injector. In order to understand disintegration precess, we measured droplet diameter, velocity and spray distribution by the PDPA(Phasse Doppler Particle Analyzer) system. Also spray was visualized by using Nd-Yag flash photography. From the test results, the liquid column emerging from the injection orifice is mainly controlled by the rotational speeds. Furthermore, droplet diameter(SMD) and spray distribution were strongly influenced by the diameter of the injection orifice.

• Korean Journal of Biological Psychiatry
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• v.9 no.1
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• pp.62-67
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• 2002

Objective:There is increasing evidence that free radical-mediated CNS neuronal dysfunction is involved in the pathophysiology of schizophrenia. This study was performed to examine the relationship between antioxidant defense system and schizophrenia by analyzing polymorphism of catalase gene, an antioxidant enzyme. Method:Genotype and allele frequencies in the promoter region in the catalase gene using restriction fragment length polymorphism were studied, comparing 155 Korean controls with 167 Korean schizophrenics. Results:No difference was found between the schizophrenics and the controls in genotype and allele frequencies of HinfI polymorphism in the catalase gene. Significant difference was found between the female schizophrenics and the female controls in the genotype distribution(${\chi}^2$=11.096, df=2, p=0.004). Conclusions:The results do not support an association between polymorphism of catalase gene and schizophrenia. However, this study suggests that HinfI polymorphism in the catalase gene could be associated with female schizophrenics.

• Korean Journal of Biological Psychiatry
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• v.4 no.1
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• pp.74-83
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• 1997

With increasing tendency of incidence and interest for the late onset schzophrenia, concerns about whether this disorder is etiologically or phenomenogically distinctive entity or not have increased also. To clarify the disease entity of the late onset schzophrenia and the role of structural brain changes in its etiology, authors tried to prove following hypothesis : Are there any evidences of structural brain changes in the lateonset schizophrenia? ; If present, are they not different from those of the early-onset schizophrenia or progressive schizophrenia? ; And are they not different from those of senile dementia? Subjects were 6 patients with the late-onset schizophrenia, 6 patients with the early-onset schizophrenia, 6 patients with progressive schizophrenia, 6 patients with Alzheimer's dementia, and 6 controls. We measured regions of interest of the magnetic resonance images by computer assisted planimetry using the AutoCad and digitizer. Our study results may suggest that the third ventricular enlargement and a reversal of normal difference between left and right temporal lobe and left-right difference in posterior lateral ventricle are common brain pathology for all types of schizophrenia including the late onset schzophrenia. And also suggest that brain structural changes of the late onset schizophrenia are related with neurodevelopmental abnormality rather than degenerative change.

• Journal of Life Science
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• v.8 no.1
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• pp.60-66
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• 1998

The mototic and meiotic chromosomal characteristics of ICR mice were investigated with G-and C-banding techniques. For the puposes, the chromosomal preparations were made with the modified air-drying method of Imal et al. Chromosomal analysis using testis could be observed mitotic as well as meitotic chromosomal behaviors, and the centromeric regions of all chromosomes including X chromosome were strongly stained in C-banded preparations. Nineteen autosomal bivalents and a single uniequal terminally associated X-Y bivalent in normal cells were observed during the late prophase and the metaphase of the meiosis I. The mean frequencies of previously dissociated X-Y chromosomes in the primary apermatocytes of the control group were 7.45%, but the frequencies of X-Y dissociation in the alkylating agents-treated group were about 3-4 times higher than that in the control group. Application of C-banding in meiotic stages could be certainly distinguish between vibalent type and univalents type of sex chromosomes.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.199-210
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• 2016

This study was conducted to examine the mediation effect of narcissistic personality traits and schizophrenic personality traits on the relationship between smartphone addiction and relational aggression of middle school girls. Data from 378 girls in Kyungki and Chungchoeng areas were analyzed. Main results were as follows. First, smartphone addiction showed significant positive correlations with narcissistic personality traits, schizophrenic personality traits and relational aggression. Both personality traits also showed positive relationship with relational aggression. Second, narcissistic personality traits fully mediated the relationship between smartphone addiction and reactive relational aggression. Third, schizophrenic personality traits partially mediated the relationship between smartphone addiction and relational aggression. Finally, clinical implications for adolescent girls at high risk of smartphone addiction and suggestions for future studies were discussed.