• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 1998.10a
• /
• pp.25-25
• /
• 1998

최근의 선진국의 전략미사일에 사용되는 추진제 개발 방향은 고에너지, 저민감, 무연 및 무공해 추진제를 목표로 하고 있다. 현재까지 가장 널리 사용되어온 AP는 성능이나 기계적 특성에서 우수한 산화제이나 로켓 모타 배출기체 중에 HC1을 생성함으로써 2차 연기를 생성하며, HC1 자체가 인체에 유해한 물질이라는 단점들을 가지고 있다. 또한 RDX나 HMX는 에너지가 높은 반면 쇽(shock)에 대해 매우 민감한 단점을 가지고 있다. AN은 이러한 HC1을 생성하는 AP의 단점과 쇽에 민감한 RDX와 HMX의 단점을 해결할 수 있는 대체 산화제로 사용할 수 있으나, 성능이 대외적으로 떨어지며 상변이와 흡습성이 높은 단점이 있다. ADN은 -100~+10$0^{\circ}C$범위에서 상 변이가 없고 밀도는 1.801g/㎤, Hf는 -290cal/g이다. ADN을 산화제로 사용하면 HTPB/AP 추진제와 동등하거나 그 이상의 성능을 갖는 추진제를 만들 수가 있으며, 유해 기체인 HC1을 배출하지 않음으로 인하여 2차 연기를 없애는 장점이 있다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2000.10b
• /
• pp.371-373
• /
• 2000

본 논문에서는 분절 특징을 모수적 궤적 모델을 이용하여 표현하고, 이 특징을 분절 HMM(segmental HMM)의 입력으로 하는 음성 신호의 모델링 방식을 제안한다. 분절 특징은 음성의 경향을 나타내는 궤적으로 표현되고, 그 궤적은 연속되는 프레임 상에서 전이 정보를 포함하도록 디자인 행렬과 다항식의 회귀 함수를 이용하여 구해진다. 이 궤적을 분절 HMM에 적용하기 위하여, 외적 분절 변이와 내적 분절 변이에 대한 확률 분포 표현을 개선하였다. 제안된 방법의 효과를 살펴보기 위하여 TIMIT 데이터 베이스를 이용하여 실험한 결과, 제안된 분절 특징은 음성 신호의 인접한 프레임간의 상관관계를 표현하는 동적 특징과 같은 효과를 보였으며, 1차 미분계수를 포함하여 분절 특징을 구한 경우에는 기존의 특징 표현보다 좋은 성능을 보였다.

• Journal of The Korean Society of Inherited Metabolic disease
• /
• v.11 no.1
• /
• pp.84-87
• /
• 2011

윌슨병은 ATP7B의 결함에 의해 발생하는 질환으로 구리 대사 이상질환이다. 구리대사의 이상은 체내에 구리의 축적을 유도하며, 이에 따르는 산화스트레스, 염증반응, 세포소멸사의 환경 조성, 마이토콘드리아의 손상 등이 동반되는 것으로 알려져 있다. 윌슨병은 간질환으로 발현하거나, 신경학적 증상으로 발현하는 환자도 있으며, 일부 환자는 무증상적 시기에 발현하기도 한다. 우리나라의 윌슨병 237 가계를 대상으로 한 연구에서 발현 표현형에 따른 임상상의 차이를 발견할 수 있었다. 또한, 이러한 표현형의 차이는 ATP7B의 유전형과도 일부 상관관계를 보이고 있었는데, 돌연변이의 종류나 위치에 따른 발현 임상상의 차이를 확인할 수 있었다. 그러나, 이외의 부위나 한국인에서 흔한 돌연변이에 따른 표현형은 상관관계를 밝힐 수 없었다. 향후 표현형의 다양성에 영향을 주는 요소를 찾아내고 이들이 임상경과에 미치는 영향을 밝히기 위한 노력이 필요하다.

• Radiation Oncology Journal
• /
• v.19 no.2
• /
• pp.107-112
• /
• 2001

Purpose : To determine the prognostic significance of p53 mutations in advanced supraglottic cancer patients. Material and Methods : Twenty-six patients with pertinent tissue materials among 60 patients diagnosed as advanced supraglottic cancer in Kyung Hee university hospital and received total or partial laryngectomy followed by radiation therapy were enrolled. Immunohistochemical staining using DO7 monoclonal antibody was peformed. Tumor specimens were analyzed for p53 mutations in exons 5 through 8 by using PCR-SSCP analysis followed by DNA sequencing of all variants. Results : p53 mutations were present in 8 cases among 26 patiets. Mutations within exon 5 were 3 cases, exon 6 were 4 cases, and exon 7 was 1 case. Mean survival time was 70.2 months in patients without mutations, 61.3 months with mutations but there was no statistically significant differences (p=0.596). Mutations were $25\%$ in stage III and $36\%$ in stage IV but there was no statistically significant differences (p=0.563). Mutations were $25\%$ in lymph node negative group and $42\%$ in lymph node positive group but there was no statistically significant differences (p=0.437). Conclusion : The presence of p53 mutation detected by PCR-SSCP is not associated with survival, stage and lymph node status.

• 한국가시화정보학회:학술대회논문집
• /
• 2005.12a
• /
• pp.103-106
• /
• 2005

Lattice Boltzmann method is a new numerical method of investigating the fluid flow which have been solved by Navier-Stokes equation recently. It is known that making the single and parallel algorithms of the Lattice Boltzmann equation is easier than those of Navier-Stokes equations. Also, we can simulate the two phase flow using either the 'Interaction Potential model ' introduced by Shan and Chen. In this paper, we first compared the 3D cavity results of Lattice Boltzmann method with other numerical results for validation and showed the 3D phase transition and its simple application by using the ' Interaction Potential model'

• Proceedings of the KAIS Fall Conference
• /
• 2002.05a
• /
• pp.74-76
• /
• 2002

항균성 및 원적외선 방사량이 높은 원적외선 방사 항균 글라스 및 글라스 세라믹스의 양산화를 위한 유리 용융에 있어 대량용융의 가능성을 확인할 수 있었으며, 열처리온도는 5Li₂Oㆍ36CaOㆍ20TiO₂ㆍ27P₂O/sub 5/와 1Ag₂Oㆍ4Li₂Oㆍ36CaOㆍ20TiO₂ㆍ27P₂O/sub 5/ 조성에서 최적핵형성온도가 620℃, 최적결정성장온도가 각각 78℃, 800℃였다. 원가절감을 위산 건식법과 습식법의 결정상분석의 결과 피크의 차이는 거의 없었다. 이온교환의 경우 5.0mol AgNO₃수용액에 담지한 시편에서는 많은 LTP 결정상이 AgTP 결정상으로 변환되기 시작하여 1.0omol 농도의 AgNO₃ 수용액에서는 결정상의 주피크가 AgTP 절정상으로 변이 되었다. 이 결과로 AgNO₃ 수음액 0.5mol 농도 이상의 이온교환시 항균특성에 있어서도 매우 유리하리라 예상되어진다.

• Asian Journal of Turfgrass Science
• /
• v.15 no.3
• /
• pp.127-136
• /
• 2001

A field trial was initiated to examine the range of inter- and intraspecific variations in morphological and phenological traits with five different accessions of smooth and large crabgrass. In addition, a controlled environment study was conducted to determine the phenotypic plasticity among the accessions of both species in response to 4 daily tempera-ture differentials. In the field experiment, significant inter- and intraspecific variations of smooth and large crabgrass were observed in morphological traits such as leaf length and width. However, most phenological traits were not substantially different between the species and among the accessions of each species. The first seedling emerged at the same time, requiring 9~ 10 days, regardless of the accessions and species. In a controlled environment study, all accessions of each species responded similarly to the 4 temperature differentials in seedling emergence, indicating seedling emergence was not a plastic trait. These results suggest that predicting crabgrass seedling emergence could be independent of geographical regions in the US.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.28 no.1
• /
• pp.115-121
• /
• 1983

This experiment was conducted to investigate the growing process, nitrogen content of leaves and grain weight of the tillers of three wheat and one barley cultivars under space planting condition. The rates of the ear-bearing tillers were highest in the main stem (MS) and followed by the Ist, 2nd, 3rd tiller of the first order tiller. The leaf emergencies on main stem and tillers of barley were found simmilar results to synchronously emerging leaf theory reported by katayama, however, one or more leaves were emerged from the tillers of wheat comparing to the theoretical numbers. The orders of the ear primordia development were MS 1st 2nd 3rd tiller. The differences of ear development between main stem and tillers were greatter in wheat than in barley. Total nitrogen content in leaf decreased accompanying with growth and the highest content were found on the higher ordered tillers. The order of the proportion of each stem grain weight to the grain yield per unit area was MS > 1st≒2nd > 3rd tiller.

• Investigative Magnetic Resonance Imaging
• /
• v.1 no.1
• /
• pp.142-147
• /
• 1997

Purpose: To compare the effectiveness of the in-phase (IP) sequence and the opposed-phase (Op) sequence in the detection of focal hepatic lesions in the single breath-hold hepatic MR imaging with fast gradient T1-weighted pulse sequences. Materials and Methods: IP and OP T1-weighted breath-hold imaging was performed using fast gradient echo sequences in 45 patients referred for known focal hepatic lesions, in which 78 lesions were detected. Three blind readers independently reviewed the images for lesion detectability. The signal-to-noise ratio (SNR) of the liver, the lesion-to-liver contrast-to-noise ratio (CNR) and the liver-to-spleen CNR were also compared. A consensus was reached by three readers to determine which sequence is better in image quality. Results: On OP images, 61(78%), 61(78%), and 63(89%) lesions were correctly identified for reader 1, 2 and 3, respectively. On IP images, 66(85%), 65(83%), and 65(93%) lesions were detected for each reader, respectively. When two image sets were combined, 71(91 %), 69(88 %), and 76(97%) lesions respectively were detected for each reader. In cases of hepatocellular carcinoma, liver-to-Iesion CNR was greater on the OP images(p (0.05), but in other lesions significant difference was not demonstrated. Liver-to-spleen CNR was higher on OP images(p ( 0.1), but the SNR of the liver was higher on the IP images. Conclusion: Use of both IP and OP imaging can be helpful to avoid erroneous missing of some focal hepatic lesions.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.25 no.4
• /
• pp.43-58
• /
• 1980

The study was intended to know the responses of the nitrogen application levels (3, 6, 9, 12 and 15kg ai per $1O^a$) to grain yield and quality of two-malting barley, Golden melon and Hyang maek in 1980. There was investigated chlorophyll content, dry weight, heading, grain yield, yield components, contents of protein, fat and carbohydrate and activity of $\beta$-amylase and invertase. Nitrogen increment was effective to increase of number of grains per spike and number of spikes per unit area, increase of protein content and decrease of $\beta$-amylase activity, but it was not recognized the yield increase under the 12% protein content.