• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2277-2278
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• 2008

전력계통에서의 과전압은 계통의 상태 또는 외부상태인 대기의 방전의 결과로써 기원한다. 낙뢰에 의한 뇌서지는 여러 과전압 중에서 가장 큰 전압을 가진다. 절연요구사항에 대한 뇌 과전압의 크기를 특정화하고, 절연 섬락을 발생하는 위험한 뇌격전류를 발견하는 것은 전력계통의 설비 보호를 위한 중요한 요소이다. 본 논문에서는 과도해석 프로그램인 EMTP를 이용하여 송전선로 및 철탑을 모델링하고, 낙뢰에 인한 과전압이 발생하였을 때 송전선로 및 철탑에 어떻게 영향을 미치는지 모의하고 분석하였다.

• Journal of the Korean Geographical Society
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• v.41 no.1 s.112
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• pp.73-93
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• 2006

Despite of ecological and landscape importances and public popularity of Pinaceae, not much scientific informations are known about Korean Pinaceae. Present work aims to understand the biogeography of Korean native Pinaceae, i.e., taxonomy, phylogeny, origin, life form, distribution, dispersal and migration. Korean native Pinaceae consists of five genera and sixteen species. Pinus is systematically closely related to Picea and Larix, but Abies is related to Tsuga. Boreal conifers which have migrated from NE Asia during the Pleistocene glacial epochs successfully survived, but now confined to the alpine and subalpine belts of the Korean Peninsula mainly due to climate warming since the Holocene. Species, such as Picea pungsanensis and Abies koreana have gradually adapted to local environment, and later became an endemic species of Korea. Disjunctive distribution of Pinus parviflora and Tsuga sieboldii are also indicatives of climate change of the Pleistocene. Major dispersal agent of pine trees with winged seed is wind, but wingless pine tree seeds seem to dispersed by birds and rodents. Pine trees with bigger wings are easily dispersed by wind, and now show broader distribution. Species of Pinaceae with disjunctive distribution on the alpine and subalpine belts of both North and South Korea seems to be more vulnerable to global warming.

• Journal of Life Science
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• v.18 no.7
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• pp.907-911
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• 2008

Radish (Raphanus sativus L.) is one of very important crop plants in the world. It is very important to determine hybrid seed quality in the production of hybrid Brassica vegetable seeds to avoid unacceptable contamination with self-inbred (sib) seeds. The allozyme for evaluating seed purity in a commercial $F_1-hybrid$ radish cultivar is demonstrated. Three hundred sixty seeds from the male and female harvest were subsequently screened for seed purity using 27 isozyme loci. Especially, F1 hybrids of radish, Per-1 ($aa{\times}bb$), Lap-1 ($aa{\times}bb$), Est-1 ($aa{\times}bb$) were presented clear hybrid bands. Est-1 locus revealed that 15 (8.3%) seeds from the female harvest and 26 (14.4%) seeds from the male harvest were sibs. It maintains higher than average level of genetic diversity compared with their correspondent parents. Shannon's index of phenotypic diversity (I) of hybrids was the highest of all accessions (R. sativus L. cv. Daepeng, R. sativus L. cv. Backza, and their hybrids). The allozyme may lead to a better insight into the hybrid seed purity.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.371-376
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• 2017

In a nationwide survey of the occurrence and density of the migratory locust (Locusta migratoria), high density was continuously observed in the reclaimed areas of Mangun-myeon in Muan-gun, Jeollanam-do, and Sanye-myeon in Haenam-gun, Jeollanam-do, Korea. We have analyzed the nucleotide sequences of NADH dehydrogenase subunit (NAD) 2, NAD4, and NAD5 genes in order to determine the origins of the migratory locusts at two sites. According to the analysis, the migratory locusts in Haenam-gun were closely related with those in Liaoning Province and Heilongjiang Province in the northeast China. In contrast, the migratory locusts in Muan-gun were most similar to those in Japan. Because Korean migratory locusts were not included in the previous global study on the evolution and migration of migratory locusts, we did not know the origin of Korean migratory locusts, earlier. Phylogenetic analyses this study suggested that the migratory locusts from the northeast Chinese population might have migrated and settled in Haenam-gun in Korea. Moreover, another northeast Chinese population might have migrated to Muan-gun in Korea though Sakhalin, Russia and Hokkaido, Japan. However, the possibility that the migratory locusts moved from northeast China might be isolated from each other in Korea, and that the Muan population might migrate to Japan cannot be excluded.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.175-178
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• 2004

선박의 수중방사소음은 다양한 기계류나 추진기 혹은 선체와 유체간의 상호 작용으로 인하여 여러 형태의 특성신호로 나타나게 된다. 이는 선박의 운용조건, 장비 회전특성 및 내부구조에 따라 스펙트럼상에 상이한 주파수로 확인됨은 물론, 신호의 출현 형태에도 다양성을 보이고 있다. 일반적으로 선박소음은 속력 종속적인 추진 계통 성분과 비종속적인 보기류 신호로 구분되나 다수의 신호성분이 혼재되어 발생기원을 분류하는 것은 복잡한 과정을 거쳐야 한다. 본 연구에서는 이러한 점을 해결하기 위해 선박의 Tonal성 신호를 자동으로 탐지하고 분류하기 위해 규준화된 스펙트로그램 상에서 연속되는 신호에 가중치를 주어 지속성 신호여부를 판별한 후에 정해진 임계치를 초과하는 성분을 Tonal로 선정하였다. 선정된 Tonal에 대해 주파수선의 대역특성 및 시간 변동성에 대한 패턴인식 방법을 적용하여 Tonal의 발생기원이 속력 종속/비종속적인지를 자동으로 판별하는 알고리즘의 유용성에 대한 결과를 기술하였다.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.491-492
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• 2004

선박의 수중방사소음은 다양한 기계류나 추진기 흑은 선체와 유체간의 상호 작용으로 인하여 여러 형태의 특성신호로 나타나며, 속력 종속적인 추진계통 신호 성분과 비종속적인 보기류 신호 성분이 혼재되어 다수의 신호성분으로 나타난다. 또한 토널 신호의 세기와 바다의 음향 전달 특성 등으로 인하여 신호가 미약하게 되거나 끊어져서 불연속하게 나타나기도 한다. 본 연구에서는 이러한 점을 해결하기 위해 선박의 Tonal성 신호를 자동으로 탐지하고 분류하기 위해 스펙트로그램 상에서 연속되는 신호에 가중치를 주어 지속성 신호여부를 판별한 후에 정해진 임계치를 초과하는 성분을 Tonal로 선정하였으며, 선정된 Tonal 신호의 발생 기원이 속력 종속/비종속적인지를 자동으로 판별하는 알고리즘을 실제 선박 방사소음에 대해 적용한 결과에 대해 보고한다.

• Journal of Plant Biotechnology
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• v.43 no.2
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• pp.151-156
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• 2016

Medicinal plants resources are becoming important assets since their usages have been expanded to the development of functional foods for human health, natural cosmetics, and pharmaceutical industries. However, names are different from each country and their phylogenetic origins are not clear. These lead consumers to be confused. In particular, when they are morphologically similar and distributed as dried roots, it is extremely difficult to differentiate their origins even by specialists. Recently, molecular markers have been extensively applied to identify the origin of many crops. In this review, we tried to overview the current research achievements for the development of suitable 'origin identification' regarding to the differentiation of Angelica species. Furthermore, more advanced techniques including amplification genome based marker analyses are also discussed for their practical applications in the authentication of particular medicinal plant in Angelica species.

• Korean Journal of Heritage: History & Science
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• v.54 no.1
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• pp.100-119
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• 2021

This paper has been written to verify the existing theory that districts occurred independently in various parts of the world, including the Korean Peninsula. Song Giho (2006) claims that the origin of the Gudle, is an example of polygenism that occurred in various areas in the world, including the Korean peninsula. This argument has been corroborated by a large number of researchers. However, it is difficult to understand the lineage of Gudle and its process of development, if a theory of polygenism is continued to be taken into account. The place which is targetet by this theory is the North-West area of the Korean peninsula, south of Primorsky Krai, and in the northern area of Zabaikal-Mongolia. This means that these areas developed independently because they were far from each other and had no direct cultural relationship. However, the structure of Gudle, shape, and assemblages of earthenware it cannot be explained by polygenism, as they are the same in every place. Furthermore, it is also questionable as to the timing and region of emergence of the culture in East Asia over a limited time frame of 3-2 BC. Gudle are formed by furnaces with roofs and walls, Gorae, which saves heat, and it has smoke ventilation that draws smoke out. Therefore, the Gudle is not a structure that anyone can make without advanced technical understanding. So far, the only facility with furnaces and smoke ventilation that appear before the Gudle is Buttumak. Thus, the Gudle is likely to have been invented in the place where Buttumak were used. The area as known for the origin of Gudle was observed to verify the existence of the Buttumak's structure, but none of these facilities were found. The Gudle suddenly appeared within a new culture that had never existed before. That means that none of the three places had the conditions under which the Gudle could be invented, so it must have been introduced from outside. In conclusion, the three places that I mentioned above are not the origin of Gudle. So, the origin of Gudle has to be found elsewhere.

• Journal of The Korean Association For Science Education
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• v.23 no.5
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• pp.470-483
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• 2003

This study analyzed the evolutionary content in 13 textbooks developed from the first to the 6th high school biology curriculum, The content analysis of textbooks, which were delineated nine component, was performed on the 80 evolutionary categories, According to the result, the proportion of the total evolutionary content in textbook increased from the textbooks developed by the Ist curriculum to the textbooks developed by the 6th curriculum, but the proportion of 'main narrative' in total evolutionary content was gradually decreased. It also showed that biology curriculum and points of view of textbook writers influenced on the proportion of evolutionary contents. On the whole, the topics of analysed textbooks exhibit insufficient diversity, Any categories- 'group selection', 'gene selection', 'gaps in fossil record', 'co-evolution', 'punctuated equilibrium', 'mosaic evolution', 'place of labor in human evolution', 'human race differentiation', 'criticism of "ontogeny recapitulates phylogeny", and 'human activities affecting evolution' - were not treated and others - 'theory of neutralism', 'theories of major episodes(excepting extinctions) found in the geologic time scale', 'sympatric speciation', 'clinal and area-effect speciation', 'polyploidy and evolution', 'gradualism' and 'evolution and origin of mammals' - were treated very lightly, the most emphasized topic was 'phylogeny in general' and 'formation of precells', 'miscellaneous' in the order of emphasis. 'Theory of natural selection' was lightly treated as just one of evolutionary theory though it should be emphasized as major theme of evolution. Also, the law of recapitulation, of which biologists doubt the validity, was discussed as an evidence of evolution in some textbooks. And the agents of genetic equilibrium disruption like genetic drift and migration were treated as of little importance. On the basis of above result, it was suggested that the textbook writers introduced the more meaningful evolutionary topics focused the theory of natural selection in explanation of evolution and evolution theory.

• Journal of Life Science
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• v.17 no.11
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• pp.1593-1595
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• 2007

In the study of investigate the expression and effects of adrenomedullin (AM) in the tissue injured by ethanol in our laboratory, there were lymphosarcomas involving mesenteric lymph node and intestine discovered in experimental mice. Lymphosarcoma is probably the second most common spontaneous neoplastic disease, the incidence of which is dependent on the strain of mouse. The diagnosis of lymphosarcoma was based on gross and light microscopic studies. Crossly, the excised intestine and mesentery showed soft-to-firm, cream-colored, displayed protuberance into the lumen. The neoplastic cells had mainly infiltrated into the mucosal and mesenteric lymph node, and have round hyperchromatic nuclei and a small amount of cytoplasm. The origin of these tumor cells was determined by immunohistochemistry positive of CD20, CD3 and Vimentin.