• Korean Journal of Ecology and Environment
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• v.51 no.2
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• pp.174-183
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• 2018

In the Sumeunmulbaengdui Wetland Protected Area of Jeju Island, there exists a unique pond, a so-called 'Ohmi', which is likely to be an oasis supporting the wildlife and escaped-livestock. We exquisitely described the diversity and distribution of plant community of the Ohmi. Despite its small area, six syntaxa were identified: Sphagnum community of peat bog type, Nymphoides coreana community of the floating-leaf limnetic vegetation, Scirpus triangulatus community and Schoenoplectus hotarui community of the littoral zone vegetation, and Deinostema violacea-Eleocharis congesta community and Eriocaulon atrum-miquelianum community of the ephemeral vegetation. A zonal distribution of plant communities along the water depth was recognized. The Sphagnum islets regarded as a typical component of peat bog, in Korea were first described at the center of the Ohmi. We conclude that the Ohmi is a primeval keystone habitat of the Sumeunmulbaengdui intermediate moor with a less oligotrophic ombrotrophic environment.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.3
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• pp.181-189
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• 2011

The smooth construction and operation of nuclear facilities requires understanding and support of both the local residents and the national people. It is essential that our country, which should maintain using nuclear energy for national energy security and economic growth, shall improve the social acceptance of nuclear energy. In order to identify the level of social acceptance of nuclear energy, this study investigated the perception of the local residents in Gyeongju and the public in other areas on a nuclear power plant and a low- and intermediate-level radioactive waste disposal facility through an individual interview. The subjects of the investigation were 450 persons. This study identified that perceptions of the respondents were somewhat dependent on the residential area, and derived the implications to be reflected in establishing the customized public-relation strategies.

• Korean Journal of Plant Resources
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• v.22 no.3
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• pp.266-272
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• 2009

Morphological characteristics of leaves, trichomes and acorns were investigated in 6-year-old artificial hybrids of Q. aliena ${\times}$ Q. mongolica var. crispula and Q. serrata ${\times}$ Q. mongolica var. crispula. Leaf shapes of Q. aliena ${\times}$ Q. mongolica var. crispula $F_{1}$ were obovate and resembled to that of Q. aliena. But several characters including the size of leaf and petiole and the shape of leaf base resembled to those of Q. mongolica var. crispula. In F1 hybrids, small stellate hairs distributed sparsely on the abaxial surface and their lay length was intermediate between both parents. There were no big differences on characters of nuts and cupules between both parents and $F_{1}$ hybrids. Leaf shapes of Q. serrata ${\times}$ Q. mongolica var. crispula $F_{1}$ were obovate-elliptic, and the leaf shape and leaf base and the length of petiole resembled to those of Q. mongolica var. crispula, but leaf size and serration resembled to those of Q. serrata. The number of serration in a leaf was intermediate between both parents. Small stellate hairs distributed sparsely and large single hairs were mixed on the reverse side of leaves. there were no big differences on the number and size of stellate hairs between $F_{1}$ hybrid and Q. serrata. It is able to distinguish $F_{1}$ hybrids from both parents by the size leaf size and shapes, leaf base and serration, petiole length and trichome type in the leaf.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2010.05a
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• pp.3-3
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• 2010

소나무에서 추출해낸 천연유기유황(Natural Sulfur)의 의학적 가치는 1972년 Jacob 박사와 Herschler 박사가 오래곤 과학대학에서 천연식이유황(Natural Sulfur/MSM)을 가지고 표피조직에 미치는 영향을 구명하면서 keratin 단백질에 대한 연구가 활성화 되기 시작하였다. 세포내 골격물질은 크게 형태와 조성에 따라서 actin microfilament, microtubule, 그리고 intermediate filament(IF)로 구분된다. keratin의 특성은 keratin intermediate family중에서 K17 IF가 새로운 기능을 나타내는데 피부세포의 성장에 핵심적인 조절 역할을 한다는 사실이 밝혀 지면서 Dr. Pierre A. Coulombe(The Johns Hopkins University School of Medicine)연구실은 브로컬리와 같은 십자화과 식물 등에 과량 존재하는 항산화 및 항암물질인 sulforaphane이 K17의 발현을 특이적으로 증가시킨다는 것을 알아내어 피부박리와 같은 피부손상을 기능적으로 복구시킬수 있음을 확인하였다. 현재는 수포성 표피박리증 환자군의 많은 부분을 차지하는 K14 돌연변이와 동일한 유전적 변형을 일으킨 생쥐모델을 이용한 약물 효과 검증과 전 임상단계의 인체실험을 함께 진행중에 있다. Mark E. Van Dyke 박사(Wake Forest Institute for Regenerative Medicine Medical Center)는 인간의 머리털에서 유래된 keratin으로 외상에 의한 신경 절단이나 압좌(압박손상)는 현재 다른 부위의 신경을 잘라 이식하거나 절단된 신경 양끝을 인공도관(conduit)으로 연결해 신경재생을 유도하는 미세수술을 시행하게 되는데, 신경재생을 유도하는 도관에 keratin을 주입하면 신경이식과 맞먹는 신경재생 성공률을 기대할 수 있다고 하였다. 앞으로는 동물성 keratin뿐만 아니라 식물성 keratin도 함께 연구할 필요가 있다. 동물성 keratin의 농업적 이용은 가금류 깃털의 keratin을 축출하여 친환경 육묘용 용기를 만드는데 있다. 이 용기는 자연조건에서 생분해될 수 있는 특성을 갖고 있다.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.85-92
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• 2016

Since the power density of the VHTR(Very High Temperature Reactor) is lower, there is less possibility of core melt. VHTR has no risk of explosion caused by hydrogen generation when the loss of coolant accident occurs, which is another advantage. Along with safety benefit, it can be used as a process heat supplier near demand facilities because coolant temperature is very high enough to be used for industrial purpose. In this paper, we designed the primary system using VHTR and the secondary system providing electricity and process heat. Based on that 350 MW thermal reactor proposed by NGNP(Next Generation Nuclear Part), we developed conceptual model that the IHX(Intermediate Heat Exchanger) loop transports 300 MW thermal energy to the secondary system. In addition, we analyzed thermodynamic behavior and performed the efficiency analysis and optimization study depending on major parameters.

• Tunnel and Underground Space
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• v.21 no.6
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• pp.526-535
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• 2011

A new failure criterion for concrete, which takes into account the effect of the intermediate principal stress, is proposed. The new criterion, which takes the advantages from both the Mohr-Coulomb and the Willam-Warnke criteria, is linear in the meridian section, while its octahedral section is always smooth and convex. Fitting the triaxial compression data with the proposed criterion shows the high performance of the new criterion. A new formula for the factor of safety of concrete is defined based on the new failure criterion and it is employed in the stability analysis of the concrete plugs installed in the pilot plant. The new formula for the factor of safety measures the degree of closeness of a stress state to the failure surface in the octahedral plane. Finally, 3-D finite element analyses of pilot plant were carried out to obtain the stress distributions in the plugs. Then, the stress distributions are converted to those of factor of safety by use of the proposed formula. Based on the distribution of factor of safety in the concrete plugs, the stability of the tapered and wedge-shaped plugs is evaluated.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.524-531
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• 2003

The usefulness of vitrification technology for low- and intermediate- level radioactive wastes was demonstrated because of high volume reduction, mechanical and chemical stability of final waste forms. Thus, a construction of the commercial vitrification plant Is currently promoted. Due to the high radiation level of the waste, shielding analysis has to be carried out for safe design in a vitrification facility. Because there has been no experience in the construction and operation of the vitrification facility in Korea, in this study, in order to get some information for help the detailed design and plan for operation in vitrification facility, shielding analysis for each facility in pilot plant is carried out by using source term from established study. For the selection of the shielding material, concrete was chosen compared to the lead because of economic advantage, weight consideration, and thermal resistance.

• Nuclear Engineering and Technology
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• v.39 no.1
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• pp.9-20
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• 2007

Design study on the Gas Turbine High Temperature Reactor 300-Cogeneration (GTHTR300C) aiming at producing both electricity by a gas turbine and hydrogen by a thermochemical water splitting method (IS process method) has been conducted. It is expected to be one of the most attractive systems to provide hydrogen for fuel cell vehicles after 2030. The GTHTR300C employs a block type Very High Temperature Reactor (VHTR) with thermal power of 600MW and outlet coolant temperature of $950^{\circ}C$. The intermediate heat exchanger (IHX) and the gas turbine are arranged in series in the primary circuit. The IHX transfers the heat of 170MW to the secondary system used for hydrogen production. The balance of the reactor thermal power is used for electricity generation. The GTHTR300C is designed based on the existing technologies of the High Temperature Engineering Test Reactor (HTTR) and helium turbine power conversion and on the technologies whose development have been well under way for IS hydrogen production process so as to minimize cost and risk of deployment. This paper describes the original design features focusing on the plant layout and plant cycle of the GTHTR300C together with present development status of the GTHTR300, IHX, etc. Also, the advantage of the GTHTR300C is presented.

• Journal of People, Plants, and Environment
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• v.24 no.6
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• pp.619-628
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• 2021

Background and objective: Native to the limestone zones of the Korean Peninsula, Zabelia tyaihyonii is a popular plant for landscaping. As it is now classified as a rare species, the conservation of its genetic resources is necessary. Methods: In this study, which aimed to understand the morphological variation of Z. tyaihyonii, 18 characteristics of Z. tyaihyonii from five habitats were examined. Results: Of these 18 characteristics, 16 characteristics showed significant differences among sites, and the coefficient of variation ranged from 5.4% (for corolla lobe number) to 31.3% (for flower number). Notable variations were observed in the size of flower and calyx lobe. When the corolla length and calyx lobe length were used as the classification key of Z. tyaihyonii, the sites were divided into those with small, intermediate, and large values. Hair was observed on the filament of all samples, a finding which conflicts with an earlier report. Rather than classifying Z. tyaihyonii into different species on the basis of corolla length (COL) and calyx lobe length (CALL) values, we recommend modifying the species description to incorporate the variation in these characteristics of interest. Principal component analysis results showed that the first main component was highly correlated with the traits related to the size of the calyx lobe (length: 0.819, width: 0.758), and the second main component was highly correlated with the traits related with the size of the inflorescence (length: 0.790, width: 0.626). Conclusion: Several notable variations were identified among the characteristics related to inflorescence and calyx lobe. There is little genetic exchange among groups, or each group is influenced by micro environmental factors, because sites that are located nearby. In addition, the difference between COL and CALL, which is used as the classification key for Z. tyaihyonii, was divided into small group, large group, and intermediate group, regardless of the sites' geographical distance.

• Korean Journal of Veterinary Research
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• v.57 no.4
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• pp.223-226
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• 2017

This study was undertaken to develop new analytical methods for assessment of anticoccidials. High-performance liquid chromatography (HPLC) was found to be a fast, reliable, and practical method. The anticoccidials used in this experiment were toltrazuril and diclazuril, and the analysis factors were specificity, linearity, accuracy, repeatability, and intermediate precision. The linearity of each anticoccidial was better than 0.99, and the accuracies were 99.5% and 99.1% with relative SD of 0.5 and 0.4, respectively. To assess whether the developed HPLC method could be effectively applied, toltrazuril and diclazuril post-market veterinary products (five products) that are currently sold were tested. The results revealed no non-compliant items and the method was applied successfully. Therefore, the newly developed HPLC method for anticoccidial assessment described in this study may be useful as a reference method in the Korean Standards of Veterinary Pharmaceuticals for the analysis of toltrazuril and diclazuril.