• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 춘계학술대회 논문집
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• pp.117-120
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• 2006

Heavy rainfall events are occurred exceedingly various forms by a complex interaction between synoptic, dynamic and atmospheric stability. As the results, quantitative precipitation forecast is extraordinary difficult because it happens locally in a short time and has a strong spatial and temporal variations. GOES-9 imagery data provides continuous observations of the clouds in time and space at the right resolution. In this study, an power-law type algorithm(KAE: Korea auto estimator) for estimating rainfall based on the rainfall type was developed using geostationary meteorological satellite data. GOES-9 imagery and automatic weather station(AWS) measurements data were used for the classification of rainfall types and the development of estimation algorithm. Subjective and objective classification of rainfall types using GOES-9 imagery data and AWS measurements data showed that most of heavy rainfalls are occurred by the convective and mired type. Statistical analysis between AWS rainfall and GOES-IR data according to the rainfall types showed that estimation of rainfall amount using satellite data could be possible only for the convective and mixed type rainfall. The quality of KAE in estimating the rainfall amount and rainfall area is similar or slightly superior to the National Environmental Satellite Data and Information Service's auto-estimator(NESDIS AE), especially for the multi cell convective and mixed type heavy rainfalls. Also the high estimated level is denoted on the mature stage as well as decaying stages of rainfall system.

• 한국작물학회지
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• 제50권5호
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• pp.301-308
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• 2005

This study was carried out to investigate the effect of stem-cutting (SC) length and portion on the major agronomic characters related with dry matter production and accumulation, and to examine their relation­ships in cassava. When cassava was planted with longer SCs or with older portion SCs, major canopy or source characters like leaf number and leaf area index developed excessively, while tuber yields could be reduced due to the decrease of root/shoot ratio, relative growth rate, root dry weight, and harvest index, particularly in the bitter varieties (high cyanide-level varieties). It was considered that the sweet varieties (low cyanide-level varieties) be early­bulked with higher tuber yield when they are planted with the 25-30 cm long SCs or with the SCs from young type to semi-mature portions of mother stems, while the bitter varieties with the 15-20 cm long SCs or with the SCs from semi-mature to hardwood portions of mother stems, respectively. However, a significant interaction between length and portion of SC was not observed in all agronomic characters.

• Natural Product Sciences
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• 제21권1호
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• pp.14-19
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• 2015

Several $19{\alpha}$-hydroxyursane-type triterpenoids and hydrolysable tannins have beneficial effects on human health. Rubus crataegifolius (Rosaceae) has the cleft simple leaf whereas R. parvifolius has pinnate compound leaves. This research was aimed to find the variation in the contents of the triterpenoids and tannins between the infected versus uninfected leaves of R. coreanus and R. parvifolius and between young versus mature leaves. Triterpenoids and tannins were quantitatively analyzed by HPLC. Six triterpenoids including tormentic acid, euscaphic acid, 23-hydroxytormentic acid, coreanoside $F_1$, kaji-ichigoside $F_1$ and niga-ichigoside $F_1$ were used for standard compounds. Gallotannins and ellagitannins were quantitatively evaluated using the indicatives of methyl gallate and ellagic acid. The infected leaves of R. crataegifolius contained higher levels of triterpenoids and tannin than the uninfected leaves; however, lower quantity of total tannin was observed in the mature leaves than in the young leaves. Although the pinnate compound leaves of R. parvifolius exhibited similar tendency of those compositional variation with R. crataegifolius each other, its contents of triterpenoids do not considerably vary. Variation of the contents of triterpenoids and tannins were particularly distinct in R. crataegifolius by growth and infection.

• 한국수산과학회지
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• 제40권3호
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• pp.141-146
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• 2007

We investigated the reproductive cycle of the striped eel catfish Plotosus lineatus. Specimens were sampled in the coastal waters of Sungsan and Jocheon, east of Jeju, Korea, from September 2001 to August 2002. The gonadosomatic index (GSI) in females and males were reached a maximum in June $(14.18{\pm}10.38)$ and July $(0.35{\pm}0.12)$, respectively. Based on histological observations and GSI variation, the reproductive cycle was classified into the following successive stages: in females, growing (September-April), mature (April-June), spawning (June-July), and degenerative and recovery (July-September) and in males, growing (August-December), mature (September-May), spent (April-July), and degenerative and recovery (June-August). The total length at 100% maturity exceeded 15 cm and the fecundity ranged from 525 to 1176 eggs. The fecundity was correlated positively with total length and body weight. Histological observations of the gonads suggest that this species is a spring-summer spawner with group-synchronous type oocyte development.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1985년도 워크샵 및 심포지엄 북한산국립공원의 식생
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• pp.35-48
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• 1985

Plastids, which are organelles unique to plant cells, bear their own genome that is organized into DNA-protein complexes (nucleoids). Regulation of gene expression in the plastid has been extensively investigated because this organelle plays an important role in photosynthesis. Few attempts, however, have been made to characterize the regulation of plastid gene expression at the chromosomal structure, using plastid nucleoids. In this report, we summarize the recent progress in the characterization of DNA-binding proteins in plastids, with special emphasis on CND41, a DNA binding protein, which we recently identified in the choloroplast nucleoids from photomixotrophically cultured tobacco cells. CND41 is a protein of 502 amino acids which consisted of a transit peptide of 120 amino acids and a mature protein of 382 amino acids. The N-terminal of the 'mature' protein has lysine-rich region which is essential for DNA-binding. CNA41 also showed significant identities to some aspartyl proteases. Protease activity of purified CND41 has been recently confirmed and characterized. On the other hand, characterization of accumulation of CND41 both in wild type and transgenic tobacco with reduced amount of CND41 suggests that CND41 is a negative regulator in chloroplast gene expression. Further investigation indicated that gene expression of CND41 is cell-specifically and developmentally regulated as well as sugar-induced expression. The reduction of CND41 expression in transgenic tobacco also brought the stunted plant growth due to the reduced cell length in stem. GA3 treatment on apical meristem reversed the dwarf phenotype in the transformants. Effects of CND41 expression on GA biosynthesis will be discussed

• Fisheries and Aquatic Sciences
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• 제9권1호
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• pp.1-6
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• 2006

Mature spermatozoa of dark chub Zacco temmincki (Temminck and Schlegel), were examined under a scanning electron microscope (SEM) and a transmission electron microscope (TEM). The spermatozoa have a spherical, homogeneously electron-dense nucleus with an axial nuclear fossa containing two laterally oriented centrioles. The centrioles, which are arranged at about a $120^{\circ}$ angle to each other, have the 9+2 microtubule structure typical of flagella. The mature spermatozoon is of the primitive anacrosomal aquasperm type. The nuclear envelope is strongly undulated and contains nuclear vacuoles of different sizes and positions. The midpiece contains six or more mitochondria and encircles the basal body of the flagellum with an axoneme covered by the plasma membrane. Cytoplasmic vesicles lie between the axonemal doublets and the plasma membrane, and encircle the anterior part of the tail. The plasma membrane of the flagellum extends laterally and forms a pair of side fins. The species showed minor differences in number and structure of mitochondria, the angle between centrioles, and total length and occurrence of the fins. These characters, especially the side fins, appear to be apomorphic and useful for determining phylogenetic relationships at the genus or family level.

• 대한수의학회지
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• 제26권2호
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• pp.201-210
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• 1986

The cycle of the seminiferous epithelia in the testis of mature Korean native cattle was divided into twelve stages, using criteria the morphological changes in the acrosomic system and the nuclei of developing spematids and germ cells. The results were summarized as follows; 1. The minimum number of tripe A spermatogonia were the average of 1.8 in both at stages I and VI, while maximum numbers were the average of 4.2 at stage XII. Some type A spermatogonia divided at stage XII to produce the type intermediate(IN) spermatogonia at following stage I. The intermediate type spermatogonia divided at stage IV to produce the type B spermatogonia at stage V. 2. The type B spermatogonia divided at stage VII to produce the preleptotene primary spermatocytes at stage XII. The pachytene primary spermatocytes divided at stage XI to produce the secondary spermatocytes at stage VII. The secondary spermatocytes observed at stag XII divided to give rise to the round spermatids at following stage I. Each numbers of the first spermatocytes and of spermatids were almost constant, respectively, through the cycle of the seminiferous epitherium. 3. The relative frequencies of each stage among stages I to XII of the cycle of the seminiferous epithelia were 6.1, 3.7, 5.2, 7.8, 2.2. 3.3, 13.8, 18.4, 11.8, 7.2, 18.1% and 2.4%, respectively.

• 식물분류학회지
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• 제53권2호
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• pp.102-109
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• 2023

The basic information of ovule and seed characteristics was investigated for five monotypic and endemic genera in the Korean peninsula as categorized by the Flora of Korea category. The carpels and seeds were sectioned with a rotary microtome. Mature seeds were coated with platinum using an ion sputter and observed using a scanning electron microscope. As a result, Abeliophyllum was found to be anatropous and a unitegmic ovule, with a slightly colliculate seed surface and exotestal seed coat type. The ovule of Coreanomecon was anatropous and bitegmic, having a distinct echinate seed surface, and exo-endotestal seed coat type with a prismatic crystal in the mesotesta. The ovule of Hanabusaya was anatropous and a unitegmic, with a long reticulate seed surface sculpture, and distinct exotestal seed coat type. In addition, a wing developed at the opposite side of the raphe bundle. Megaleranthis was an anatropous and bitegmic ovule, having a small pentagonal disk shape, a concave seed surface and exotestal seed coat type. Finally, Pentactina was also anatropous and a unitegmic ovule, reticulate seed sculpture, and endotestal seed coat type. These data will be proving to be a source of good information for securing bio-sovereignty in the near future.

• 한국도로학회논문집
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• 제14권3호
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• pp.59-67
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• 2012

본 연구는 아스팔트 포장 파손을 복구하는 보수재료에 대한 연구이다. 현재 국내에서 사용되고 있는 네가지 종류 재료들에 대하여 실내 및 현장시험을 실시하였다. 실내 시험으로 마샬안정도시험, 간접인장시험, 수침잔류 안정도시험, 휠트랙킹 시험을 실시하였다. 또한 성능시험으로는 기존 아스팔트 콘크리트 혼합물과의 수평전단강도시험을 실시하였다. 현장시험은 아스팔트 포장 도로상에서 차량바퀴가 통과하는 지점에 패칭 슬래브를 제작하여 차량 통과에 따른 공용 결과를 관찰하였다. 실내시험 결과는 현재 적용되고 있는 설계 재료들의 기준은 수침잔류 안정도를 제외하고 만족하였다. Type C가 가장 높은 수평전단강도를 나타냈다. 그러나 시공후 10일 이후부터 소성변형과 탈리와 같은 파손이 발생하였다. 따라서 현재 사용되고 있는 상온보수 재료들을 현장에 적용할 경우에 우수한 성능을 기대할 수 없어서 조기파손을 방지할 수 있는 새로운 시험방법의 개발과 적용이 필요하다.

• 대한수의학회지
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• 제24권1호
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• pp.8-16
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• 1984

The work was conducted with tole purpose of investigation on the development pattern of epididymis in accordance with the growth of meat-type cockerels. 1. Histological features of various ductules in epididymis of the cockerel on the age of weeks were as follow: within 10 weeks after hatching rete testis and connecting ductules were well developed but efferent ductules were observed in immature form. During 10th to 20th week, the lining epithelium of various ductules in epididymis was in the developing stage near to the mature form. From 21th week, various ductules were abruptly matured. Lumen of rete testis was lined by simple squamous or simple columnar epithelial cells and that of efferent ductules, having many folds and being larger than any others, were lined by ciliated pseudostratified columnar epithelium with ciliated columnar cells, clear cells and basal cells were noted. Luminal epithelium of connecting ductules was composed of ciliated low pseudostratified columnar epithelial cells, ciliated columnar cells, clear cells and basal cells. The luminal surface of epididymal ducts was pseudostratified columnar epithelium and which was composed of high columnar cells and basal cells. 2. In the India ink absorption test, India ink granules were noted above the nucleus of some cells in the efferent ductules and the connecting ductules at 7 hours after administration of India ink to the mature epididymis, but not absorbed in the other ductules. The granules reactive to acid phosphatase were most abundant in some epithelial cells of efferent ductules and connecting ductules, especially above the nucleus of cells. The granules reactive to alkaline phosphatase were noted on the luminal border of efferent ductules. The granules reactive to PAS were scattered in the epithelial cells of efferent ductules and connecting ductules.