• Fisheries and Aquatic Sciences
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• 제24권3호
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• pp.121-128
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• 2021

The variations of morphological features, density and biomass of vegetative shoots and characteristics of reproductive shoots of Zostera caespitosa were examined in Tongyeong, Korea. Morphological features such as leaf length, width and sheath length of Z. caespitosa showed significant seasonal variation (p < 0.001). The highest aboveground value was recorded in late spring to summer and the lowest value in winter. Density and biomass also showed seasonal variations. Annual average shoot density and biomass of Z. caespitosa were recorded as 1,223.4 leaf m^-2 and 5,956.9 g w.w.m^-2, respectively, and had the highest value in June and lowest values in November and January. Reproductive shoots were observed from April (13℃) to June (21℃). Pistils erected outside sheath, anther dehiscing and small embryos were found in April. Mature fruit and released seeds were found in May and June. These results suggest that this species had a high growth rate in late spring and early summer (15℃-20℃). Reproductive shoots of Z. caespitosa may initially appear at about 10℃ in spring and seed have been released at about 20℃ in fall.

• International Journal of Computer Science & Network Security
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• 제22권7호
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• pp.220-228
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• 2022

Image always carry useful information, detecting a text from scene images is imperative. The proposed work's purpose is to recognize scene text image, example boarding image kept on highways. Scene text detection on highways boarding's plays a vital role in road safety measures. At initial stage applying preprocessing techniques to the image is to sharpen and improve the features exist in the image. Likely, morphological operator were applied on images to remove the close gaps exists between objects. Here we proposed a two phase algorithm for extracting and recognizing text from scene images. In phase I text from scenery image is extracted by applying various image preprocessing techniques like blurring, erosion, tophat followed by applying thresholding, morphological gradient and by fixing kernel sizes, then canny edge detector is applied to detect the text contained in the scene images. In phase II text from scenery image recognized using MSER (Maximally Stable Extremal Region) and OCR; Proposed work aimed to detect the text contained in the scenery images from popular dataset repositories SVT, ICDAR 2003, MSRA-TD 500; these images were captured at various illumination and angles. Proposed algorithm produces higher accuracy in minimal execution time compared with state-of-the-art methodologies.

• 천문학회보
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• 제40권2호
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• pp.36.3-37
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• 2015

4C39.25 (0923+392) is a distant radio loud AGN placed at redshift 0.695. The motivation of our work is peculiar properties 4C39.25. Firstly, it has a conspicuous distinction of jet direction between kilo-parsec scale observation made by VLA (Kollgaard et al. 1990) and the parsec scale observation by VLBA (Kellermann et al. 1998). This might indicate episodic-jet activity which recently turned on. This object currently shows two stationary compact parsec-scale components which are bright jet component on east and less luminous core on west. Also, it is known that there have been superluminal jet components which are flowing from the core toward east, and then merging with the bright jet component (Marscher et al. 1991, Alberdi et al. 2000, Lister et al. 2013). Although 4C39.25 seems to be a blazar-like source having broad emission lines (SDSS) and superluminal motion, its property that jet component is brighter than the core is different from ordinary blazars. Furthermore, it has young radio galaxy-like properties such as non-variation in total flux (Alberdi et al. 1997, 2000, MOJAVE database) and high frequency peak at spectral energy distribution (Orienti et al 2007). Such complex properties led us to make recent observations to reveal precise properties and new changes of the source. We used Korean VLBI Network (KVN) and VLBI Exploration of Radio Astronomy (VERA) Array (KaVA) which provide high-frequency (23GHz and 43GHz) and high spatial resolution (1.2mas and 0.6mas). Therefore, this system is suitable for morphological and physical research on parsec scale structure. We present results for several epochs observed during 2013 to 2014, mainly focusing on morphological changes of 4C39.25 using KaVA images.

• 한국환경복원기술학회지
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• 제11권2호
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• pp.10-18
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• 2008

In this study, about 80 Kentucky bluegrass (Poa pratensis L.) ecotypes native to Korea were collected annually to analyze their morphology and growth characteristics from 1995 to 2007. Kentucky bluegrass ecotypes with superior characteristics of 'Pureundle' (Trial No. : P38), 'Sewon' (P77), 'Inje' (00034), 'Donggang' (00052), 'Hwasun' (01001), 'Pyengchang' (01071), 'Kongju' (02006), 'Chungsong' (02077), and 'Kumsan' (03005) and three foreign cultivars were transplanted to flowerpots in May 8, 2006 in order to analyze the blooming and morphological characteristics. Out of the selected superior ecotyes, six were collected on the roadsides, two were collected around paddy or dry fields, and one was collected at riverside. Length of 1st internode of 'Chungsong' was the longest (30.7cm), that of 'Pyengchang' was the shortest (12.8cm), and ecotypes showed variation in length. The 1st angle of branches of 'Donggang' was the narrowest ($141.7^{\circ}$), that of 'Hwasun' was the widest ($188.3^{\circ}$), and that of the introduced foreign cultivars were between $159.3^{\circ}$ and $166.7^{\circ}$. The number of nodes of the introduced cultivars were same (six), while that of Korean ecotypes were four to six. Length of flowering culm of 'Chungsong' was the longest (50.7cm) and while that of 'Pyengchang' was the shortest (19.2cm). 'Donggang' with the highest seed yield showed relatively high (36.8cm) inflorescence height when compared to other ecotypes. The five ecotypes of 'Sewon', 'Inje', 'Donggang', 'Pyengchang', and 'Kongju' were investigated to have relatively wide leaf width. Especially 'Sewon' and 'Inje' were investigated to have wide leaves of 4.5mm and over.

• 아시안잔디학회지
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• 제25권1호
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• pp.11-16
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• 2011

본 연구는 국내 해안 및 도서지역에 자생하고 있는 버뮤다그래스를 지역별로 수집하여 입지환경에 따른 형태적 변이 정도를 알아보고자 수행되었다. 이들 입지환경, 토양의 화학성과 형태적 특성을 조사하였다. 수집된 자생지에 따라 초장, 엽폭, 엽장, 잎털, 포복경 및 화수당 종자수 등에서 큰 변이를 보여 조사 형질 간에 다양한 변이를 보이는 것을 확인할 수 있었다. 광엽과 세엽 특성의 버뮤다그래스가 존재하고 있었으며, 광엽형의 버뮤다그래스의 경우 열악한 환경에서의 적응성이 매우 높아 중 저관리의 잔디면에 이용 가치가 높을 것으로 생각된다. 상기 입지 환경과 형태적 특성 조사 결과 및 수집된 유전자원들은 앞으로 유전자원으로서 보존 가치가 높으며, 유용유전자를 보존할 수 있는 체계가 마련되어야 할 것으로 판단된다.

• 한국자원식물학회지
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• 제24권5호
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• pp.540-548
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• 2011

고로쇠나무 11개 자연집단의 잎의 14가지 형태적 특성에 대한 변이분석을 실시하였다. Nested 분산분석 결과 14가지 양적특성들 모두에서 집단간 및 집단 내 개체 간에 유의적인 차이를 보였으며, 모든 형질들에서 총 분산 가운데 집단 내 개체 간 차지하는 비율이 집단간 차지하는 비율보다 큰 것으로 나타났다. 집단간 분화정도를 알아보고 형질간 상호비교를 위하여 표준화시킨 $D_{ij}$값은 엽신장/엽병장(0.90), 상열편폭(0.85) 및 엽신장과 중열편폭(0.83) 특성들이 다른 형질들에 비해 이탈정도가 큰 형질들로 나타났다. 또한 14가지 형태적 특성에 대한 전체평균 $D_{ij}$값은 광양(1.36)과 청양(1.30) 집단이 집단분화가 가장 큰 값을 보인반면 울주(0.30)와 정선(0.44) 집단이 가장 작은 값을 보여 조사된 집단들 중 울주와 정선집단이 고로쇠나무 잎의 형태적 특성을 대표할 수 있는 평균집단에 가까운 것으로 나타났다.

• Journal of Ecology and Environment
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• 제36권3호
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• pp.159-166
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• 2013

Oryzias latipes and Oryzias sinensis are indigenous species found in Japan, China, and other East Asian countries, including Korea. Based on morphological differences, the species have been classified distinctly. However, the range of morphological characters such as the number of gill rakers, vertebrae, and spots on the lateral body overlaps and is too vague for clear identification, so their classification based on their morphological characteristics remains uncertain. In this study, the mitochondrial cytochrome oxidase subunit I (COI) gene, which is used for DNA barcoding, was applied to clarify interspecific variation of O. latipes and O. sinensis. Intraspecific genetic diversity was calculated to identify correlations with geographic distributions. We studied two species collected from 55 locations in Korea. All individuals carried a 679-base pair gene without deletion or insertion. Between species, 525 base pairs of the gene were shared. The Kimura two parameter (K2P) distance of O. latipes and O. sinensis was 0.41% and 1.39%, respectively. Mean divergence within genera was 23.5%. Therefore, the species were clearly different. The distance between O. latipes and O. sinensis was 14.0%, which is the closest within genera. Interestingly O. latipes from the Japanese and Korean group represented 16.5% distant. These results were derived from geohistorical and anthropogenic environmental factors. The O. latipes haplotypes were joined in only one group, but O. sinensis was divided into two groups, one is found in the Han River and upper Geum River watershed; the other is found in the remaining South Korean watersheds. Further studies will address the causes for geographic speciation of O. sinensis haplotypes.

• 대한토목학회논문집
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• 제34권3호
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• pp.805-812
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• 2014

본 연구에서는 하상변동의 고려가 물리서식처 모의에 미치는 영향을 검토하였다. 이를 위해 수리 및 이동상 계산은 CCHE2D 모형을 이용하였으며 서식처 적합도 곡선을 사용하여 서식처 평가를 실시하였다. 적용구간은 달천 유역 괴산댐 하류 수전교에서 대수보까지 약 2.5km 구간이며, 2006년 7월 홍수기 시 실측된 유량 및 수위자료를 이용하여 이동상 모의를 수행하였다. 수치모형의 검증은 실측된 수위와의 비교를 통해 수행되었으며 하상변동의 검증은 실시 하지 않았다. 물리서식처 분석은 우점종인 성어기 피라미를 대상으로 실시하였다. 고정상과 이동상 조건에서 각각 갈수량, 저수량, 평수량, 풍수량의 유랑조건에 대한 복합서식처 적합도 지수 분포를 모의하고 가중가용면적을 산정하였다. 모의 결과, 이동상 조건에서 모의구간의 상류 및 만곡부에서 복합 서식처 적합도지수가 상승하는 결과를 확인하였다. 또한 가중가용면적은 이동상 고려 시 5.4~11.3%정도 증가하는 것을 확인하였다.

• 한국자원식물학회지
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• 제25권2호
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• pp.257-270
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• 2012

국내에 분포하는 대사초절에 속하는 3분류군의 외부형태형질을 분석하고 분자계통학적 연구를 수행하여 이들 간의 유연관계를 밝혔다. 대사초절 내의 기본종인 대사초의 외부형태학 특징을 재검토하여 기존 문헌과의 차이를 파악하였으며, 식물상 문헌 및 표본을 통해 국내 분포도를 작성하였다. 문헌에 언급된 형질들 중에서 잎의 형태는 생육지 조건에 따라 변이가 심하였지만, 지하경 생장 양상, 잎과 과낭의 털의 존재 등은 종수준에서 구분하는데 좋은 형질이었다. 분자계통학적 연구에서 털대사초는 독립된 종으로 처리되는 것을 지지하였다.

• 한국환경생태학회지
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• 제29권2호
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• pp.145-161
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• 2015

This research was conducted in order to understand the hybridization between Quercus aliena Blume and Q. serrata Murray in Korea which show wide range of morphological variations within species and interspecific variations of diverse overlapping characteristics caused by hybridization. Morphological analysis (principal components analysis; PCA) of 116 individuals representing two species and their intermediates were performed. As a result, two species were clearly distinguished in terms of morphology, and intermediate morpho-types assumed to be hybrids between the two species were mostly located in the middle of each parent species in the plot of the principal components analysis. There was a clear distinction between two species in trichome distribution pattern which is an important diagnostic character in taxonomy of genus Quercus, whereas intermediate morpho-types showed intermediate state between two species' trichome distributions. Forty-two individuals representing two species and their intermediates were examined for leaf flavonoid constituents. Twenty-three flavonoid compounds were isolated and identified: They were glycosylated derivatives of flavonols, kaempferol, quercetin, isorhamnetin and myricetin. The flavonoid constituents of Q. aliena were five glycosylated derivatives: kaempferol 3-O-galactoside, kaempferol 3-O-glucoside, quercetin 3-O-galactoside, quercetin 3-O-glucoside, and Isorhamnetin 3-O-glucoside. The flavonoid constituents of Q. serrata had 20 diverse flavonol compounds including five flavonoid compounds found in Q. aliena. It was found that there is a clear difference in flavonoid constituents of Q. aliena and Q. serrata. Flavonoid chemistry is very useful in recognizing each species and putative hybrids. The flavonoid constituents of intermediates were a mixture of the two species' constituents and they generally showed similar characteristics to morpho-types. The hybrids between Q. aliena and Q. serrata showed morphologically and chemically diverse characteristics and it is assumed that there are frequent interspecific hybridization and introgression.