• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.577-584
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• 2011

To estimate level of genetic variation and genetic differentiation among populations of 3 populations in Abies koreana and 5 populations in Abies nephrolepis, 5 nSSR markers were analyzed. Except 1 locus where too many alleles were observed excessively, population genetic parameters were recalculated with 4 loci. Mean expected heterozygosities ($H_e$) were 0.292 in A. koreana and 0.220 in A. nephrolepis, respectively. In both species, positive fixation coefficient was estimated (F=0.065 for A. koreana and F=0.095 for A. nephrolepis), which suggests that there is an excess of homozygotes relative to Hardy-Weinberg expectations within populations. Relatively high degree of population differentiation was observed in A. koreana ($F_{ST}=0.063$). compared to that of A. nephrolepis ($F_{ST}=0.039$). From 3-level Hierarchical estimation of F-staticstics, only 4.9% of the genetic variation was allocated between species ($F_{PT}$), which suggested that most of genetic variation was shared between two species. On the basis of results from analysis of genetic relationships among populations, 2 populations of A. koreana (Mt. Halla and Mt. Deogyu) were genetically distinct from the populations of A. nephrolepis but a population of Mt. Jiri was allocated within a group of populations of A. nephrolepis. Populations of both species seemed to have undergone genetic drift due to gradual decrease in population size induced by global warming after the last glacier, which resulted in increase of homozygotes by inbreeding. It could be also postulated that these species might be diverged recently and It is likely that the two species have not fully speciated yet.

• Animal Systematics, Evolution and Diversity
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• v.21 no.1
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• pp.123-127
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• 2005

A new species of the genus Tethya (Demospongiae: Hadromerida: Tethyidae), Tethya songakensis, is collected from Jeju Island, Korea, by scuba diving. This new species is characterized by oxyasters, slender tylasters and spherasters with frequently branched ray. Tethya songakensis n. sp. is similar to T. simi Sara and Bavestrello, 2000 in megascleres and megasters, but it can be clearly distinguished with the latter by the shape of microasters.

• The Journal of Engineering Geology
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• v.15 no.4 s.42
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• pp.407-421
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• 2005

This study aims to investigate hydrogeological properties of the central area from Yangjeong-Dong to Sujeong-Dong in Busan Metropolitan City. For this study, pumping tests were carried out in the bedrock aquifer of Yangjeong-Dong and the unconsolidated aquifer near Busanjin railway station. The pumping test in the bedrock aquifer containing the Dongrae fault revealed specific hydraulic characteristics with respect to the fault. The pumping test in the unconsolidated aquifer revealed the hydrogeologic properties of both coastal landfill and fine sediments. It was found that the Moench's sphere-shaped dual-porosity model fits the bedrock aquifer, whereas the Neuman's uncofined aquifer model accords with the unconsolidated aquifer. The average transmissivity and storage coefficient of the bedrock aquifer are $2.75{\times}10^{-5}m^2/s\;and\;6.41{\times}10^{-5}$ and those of the unconsolidated aquifer are $8.24{\times}10^{-4}m^2/s\;and\;3.70{\times}10^{-3}$, respectively. On the other hand, slug tests gave average transmissivity and storage coefficient values of $9.84{\times}10^{-4}m^2/s\;and\;1.21{\times}10^{-2}$, respectively.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.617-622
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• 1997

격납건물내 소격실에서의 수소혼합 정도를 파악하고 격실내 균일한 혼합을 좌우하는 인자의 영향을 분석하기 위하여 소규모 혼합실험을 수행했다. 본 연구에서는 해석적으로 수립된 3차원 혼합 모델의 검증을 위하여 3차원 모사가 가능하도록 실험 장치를 구성하였다. 격납용기 내에서 수소 생성의 주원인이 되는 노심으로부터의 수소거동을 분석하기 위한 기초 실험(실험 A)과 안전주입 탱크 격실에서의 수소거동을 분석하기 위해 원형 혼합 chamber를 구상했다. 기초실험 A에서는 혼합 chamber내 축 방향으로 대칭적인 오리피스형 장애물을 설치하고 실험했고 안전주입 탱크 격실을 모사한 실험 B는 영광 3&4호기를 바탕으로 축소시켜 안전주입탱크 격실내 존재하는 두충과 안전 주입 탱크 사이의 틀을 통한 혼합체의 거동을 분석했다. 실험결과 오리피스형 장애물을 설치한 기초실험에서는 원형 띠모양의 장애물이 혼합체의 거동에 큰 영향을 주지 않는 것이 관측됐지만 안전주입탱크격실 실험에서는 격실내 장애물로 존재하는 두충이 혼합체의 거동에 큰 영향을 주는 것이 관측됐다.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.10a
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• pp.27-31
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• 1997

액상법에 의한 단분산 ZnS입자의 합성을 60~9$0^{\circ}C$에서 행하여, 반응조건이 ZnS입자의 형태에 미치는 효과를 검토했다. ZnS입자의 형태는 반응 시간의 경과와 더불어 단분산으로부터 다분산 혹은 응집체로 변화하였다. 반응 온도 60~9$0^{\circ}C$에서 초기 농도적이 중간값이고, 반응시간이 짧을 경우 입경 0.2~0.8$\mu\textrm{m}$의 구상 단분산 입자를 얻었다. 또한 Ag$_2$NO$_3$, EtOH용액, $0^{\circ}C$에서, Ag$_2$S에 의한 ZnS의 균일 피복이 가능하였다.

• Defense and Technology
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• no.12 s.286
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• pp.22-35
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• 2002

"군 소요(Requirement)"는 "과학기술(Technology)"을 이끌고 가는 견인차이다. "Technology push and Requirements pull"이란 법칙이 있다. 이 Push-Pull이란 법칙이란, 기술의 발전이 장차 전쟁수행방법에 있어서 그 기술을 적용할 군의 역할 혹은 미래군의 구상을 강요한다는 것이다. "첨단 무기체계일수록 국내에서 획득"하도록 국방과 학기술공동체(군.산.학.연)의 모든 노력을 통합하는 가시적인 조치가 절실히 필요하다. 특히, 군.방산간의 "조화와 협력"의 과학기술 기반이 구축되어 군이 방산이고, 방산이 곧 군인 풍토가 조성됨으로써, 우리도 신기술발전속도에 걸맞는 "21세기 정보화 과학화 군건설"이 가능할 것이다.

• Clinics in Shoulder and Elbow
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• v.16 no.2
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• pp.100-106
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• 2013

Purpose: The purpose of this study is to evaluate the relationship between trochlear medial facet osteophyte (TMFO) and elbow flexion in the elbow joints without trauma history. Materials and Methods: Twenty five patients, who underwent computed tomography without elbow trauma history, were reviewed. Patients were checked for osteophyte or loose bodies in the coronoid and olecranon sides. The height and length of TMFO were measured. Results: The average elbow flexion contracture was $18.6^{\circ}$, and further flexion was $112.1^{\circ}$. The TMFO height and length was 2.2 mm and 4.7 mm, respectively. The average elbow further flexion was $105.1^{\circ}$ in the coronoid block group (n=14) and $119.1^{\circ}$ (p=0.011) in the coronoid free group (n=11). The relationship between further elbow flexion and TMFO was significant with a partial correlation coefficient of 0.687(p<0.000) in the TMFO length. Conclusion: Elbow joints with longer TMFO length decrease further flexion.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.19 no.1
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• pp.85-107
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• 1993

The cosmetic fine powders were mixed with variation of mixing time(5) in the mixers (ribbon mixer, powder mixer, micropulverizer and fine impact mill). The powders were nixed with small amount of ferric oxide. as tracer. The mixed powders ere measured the particle size distribution, specific surface area and surface color with mixing time (s). The color variation, particle size distribution and specific surface area of the mixed powder exist a relationship with mining time(s) that can be expressed as mathematical equations to show the degree of the mixing of the powder mixture. The linear velocity of the impellar tip is the main factor contributing to he mixing efficiency of the mixers un this study. According to the linear velocity, he mixers used are devieded as convection mixing (ribbon mixer), sclera mixing powder mixer) and diffusion mixing (micropulverizer/fine impact mill).

• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.14-20
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• 2007

In order to examine the differences in antioxidant enzyme activities which represent defence mechanism to stressful environments, and soil properties between healthy and declining (or unhealthy) trees, we selected three sites, Witseorum, Youngsil and Sungpanak (Jindallebat). Antioxidant enzymes including Ascorbate peroxidase (APX) and Glutathione Reductase (GR), forest soil properties including soil texture, soil pH, organic matter, total nitrogen, available phosphate, cation exchange capacity, exchangeable cation content and nutrient contents in leaves of Abies koreana (Korean fir) trees were analyzed. There were no significant differences between healthy and declining trees in GR activity. However, seasonal difference in antioxidant enzyme activity was observed. GR activity was lower in June and August than that of September. Soil chemical and physical properties of each site showed a tendency that organic content, total nitrogen content, available phosphorus, cation exchange capacity and cation content were lower at the site of declining trees than the site of healthy trees.

• Journal of the Mineralogical Society of Korea
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• v.24 no.2
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• pp.111-118
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• 2011

Hydrated halloysite was formed by the low temperature alteration of trachytic tuff in onion-like spherical or curly platy forms. The Si content was higher than that of ideal kaolin minerals, indicating the possible presence of amorphous materials. The high Fe content is responsible for the platy morphology of halloysite. The leached ions precipitated as halloysite filling the interparticle pores, while trachytic glass was replaced by Si-rich amorphous materials in an hemispherical form, which was further evolved into spherical halloysite. Halloysite is one of the major alteration products of the volcanic ash in Ulleung Island underwent intense trachytic volcanism.