• 한국자원식물학회지
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• 제25권1호
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• pp.105-122
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• 2012

본 조사는 당진, 서산, 태안, 홍성, 보령, 서천 등 충남 도서지역의 관속식물 분포를 연구하기 위해 2010년 3월부터 11월까지 조사하였으며, 본 조사를 통해 확인된 조사지역 내의 소산 관속식물은 105과 326속 454종 4아종 45변종 9품종으로 총 512분류군으로 확인되었다. 조사지역내의 한국특산식물은 벌개미취, 키버들, 좀땅비싸리, 태안원추리, 새끼노루귀, 고광나무 등 총 6분류군으로 확인되었으며, 산림청지정 희귀 및 멸종위기 식물은 목련, 모감주나무, 먹넌출, 갯방풍 등 총 4분류군이 확인되었다. 식물구계학적 특정종은 I등급종은 50분류군, II등급종은 1분류군, III등급종은 11분류군, IV등급종은 4분류군, V등급종은 3분류군으로 총 69분류군이 확인되었다. 기후변화와 관련한 연구 결과에 의한 기준으로 보면 남방계가 14분류군, 북방계가 4분류군이 확인되었다. 귀화식물은 17과 46분류군으로 확인되었으며, 이는 조사된 전체 소산 식물목록 중 약 9.1%를 차지하고 있었다. 귀화식물은 군락을 형성하지 않은 상태로 주변 도서지역의 식생에 큰 영향을 주지 못하는 것으로 확인되었다. 하지만, 도서지역 간에 정기적으로 여객선이 오가며 관광객이 증가함에 따라 종수가 증가하고, 주변 도서지역에 많은 영향을 미칠 것으로 사료된다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.281-285
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• 2006

As the needs of wind energy increase, the more sites for the wind farm are required. As a part of searching for the prominent wind farm site, specially for offshore wind farm, we chose 4 sites along the southern part seashore of JeonNam province based on the analysis of the data gathered by meteorological observatory ud have gathered wind data for more than a year by use of 40m Met masts installed in the representative locations, ie. small islands of 4 different bay area. The siting for the Met masts were very limited by the geographical circumstances The wind data of those areas show a little lower annual average wind speeds, for the wind farm development, of 4m/s to 5.5m/s at the height of 40m above the ground level of the respective islands. The detail figures of one year wind data of those area are presented in this report.

• 한국항해학회지
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• 제18권3호
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• pp.19-30
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• 1994

By use of the recent tropical cyclones' data in the Northwest Pacific Ocean, the occurrence frequency and region of typhoon as well as the features of the monthly mean track were analyzed. As the result of this study, (1) mean occurrence frequency of typhoon per year is 27.5, and 68% of total typhoons were formed in July to October and shown the highest frequency in August. (2) The ave-rage duration of typhoons is 8.5 days, and super typhoon which maximum sustained surface wind speeds is more than 130 knots occurs most frequently in October and November. (3) The highest frequency ap-pears around the Caroline, Mariana and Marshall Islands, and in wintertime, typhoon occurs in lower lati-tude comparing with those in summertime. (4) The typhoon track depends upon the distribution of pres-sure system and steering current in neighbouring areas. The mean track of typhoon can be classified into three types such as westward-moving type, northward-moving type and abnormally moving type. The west-ward-moving typhoons make landfall on the southern China by way of the South China Sea in June and July, on mid-part of China in August and September, and on Indo-china Peninsula in October and Novem-ber. The northward-moving typhoons approximately move on north~northwestward track to $20~30^{\circ}N$ from the occurrence region, then recurve to the East Sea through Korean Peninsula and Kyushu Island in June and July, to the Noth Pacific Ocean along the Japanese Islands in August and September and to the North Pacific Ocean through the seas far south off the Japan in October and November.

• Ocean and Polar Research
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• 제24권3호
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• pp.197-205
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• 2002

Total magnetic field and high-resolution bathymetric data were collected over nine seamounts to the northwest of the Marshall Islands in the western Pacific. Magnetic parameters including inclination and declination were calculated from the magnetic anomalies using inversion algorithm of Plouff (1976), and a corresponding paleomagnetic pole was determined with the magnetic parameters. The paleomagnetic poles determined in this study were compared with the previous apparent polar wander path (APWP) of Pacific plate. Most seamounts of the study area have normal polarity. The study reveals that all nine seamounts in the study area formed in the southern hemisphere during the Cretaceous based on their comparison with the APWP of Pacific plate. The ages estimated from paleomagnetic poles can be divided by age into three groups: the oldest (OSM1 and OSM3), middle age (OSM2, OSM4, and 6-2), and the youngest (OSM5-1, 5-2, 5-3, and 6-1). The fermer two groups and the latter seem to be coincident with two distinct pulses of Cretaceous volcanic activity (115-90 Ma and 83-65 Ma). As a whole the seamounts at southwest of the study area are older than at those northeast.

• 한국환경과학회지
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• 제30권1호
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• pp.29-43
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• 2021

This study analyzed the status of climate-change indicator plants native to the main islands of the Korean peninsula, while elucidating their distribution characteristics. Information on flora from over 129 island locations, comprising more than 100 species of native plants, was collected, compiled into a database, and utilized as raw data. The distribution of 193 climate-change indicator plants was confirmed. The distribution area of broadleaf evergreen trees and ferns, including Mallotus japonicus and Cyrtomium falcatum, was relatively wide. In contrast, the distribution of common northern plants such as Corydalis turtschaninovii and Malus baccata was limited. If global warming persists, northern plant distribution is expected to decrease rapidly in the Korean Peninsula island region, while the northern limit line of the southern plants is expected to migrate further northward. During this process, it is likely that the plant congregation structure and species diversity within the island region will change dynamically. In this study, comparative analyses between species and regions were conducted by assessing the relative frequency of their occurrence, and six types of botanical geographic distribution patterns were noted.

• Ocean and Polar Research
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• 제28권3호
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• pp.339-352
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• 2006

Seasonal and tidal variations of density stratification in the Saemangeum waters are investigated based on synoptic CTD observations between July 2003 and September 2005. CTD data used in this study are those obtained after closing the dike No. 4 and before closing the two final gaps, the Sinsi and the Garyeok, on the Saemangeum tidal harrier. A total of 19 field campaigns comprehend a wide temporal spectrum, that is, few seasons, spring and neap tides, and high and low waters. In addition, ADCPs were anchored and CTDs were cast at three stations for 25 h in July 2005. Water columns are vertically homogeneous in autumn and winter. The vertical homogeneity persists in spring but with an occasional weak stratification in i:he northern part of the Gogunsan Islands. Increased reshwater runoff tends to stabilize the water columns and strong density stratification is established in summer. The mean potential energy anomaly (PEA) in summer used as a stratification parameter is the largest $(27.7\;J\;m^{-3})$ in the northern part of the Gogunsan Islands where the Geum River discharge dominates, the smallest $(16.9\;J\;m^{-3})$ is in the inner area of the barrier, in between the two $(21.6\;J\;m^{-3})$ in the southern part of the Gogunsan Islands. Whereas the stratification is generally strengthened in summer, strong winds or large tidal currents over the shallow depths frequently destratify the water column near the mouth of river runoff inside the tidal barrier. Periodic stratification, the development of stratification on the ebb and its breakdown on the flood, occurs in the mid-area inside the barrier induced by the tidal straining, which can also be found in the results of 25 h observation.

• 한국수산과학회지
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• 제39권spc1호
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• pp.151-164
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• 2006

We monitored the current macrozoobenthic community structure after the Sea Prince oil spill around Keumo-do and Sori-do, Korea. Macrobenthic animals were collected seasonally around Sori-Keumo do using a van Veen grab ($0.1m^2$) from October 1999 to April 2000. In total, 196 species were identified at 46 sites around Keumho-do. The mean density was 1,460 individuals/$m^2$, and polychaetes comprised 80% of the total density of the macrozoobenthic. Dominant species were the polychaete Tharyx sp. (51%), the echinoderm Amphioplus megapomus (5%) and the polychaete Lumbrineris longifolia (3%). We identified 176 macrobenthic species at 36 sites around Sori-do. The mean density was 1,068 individuals/$m^2$, and polychaetes was the most abundant faunal group, comprising 41%, followed by mollusks (24%) and echinoderms (20%). Dominant species in Sori-do were the mollusk Potamocorbula amurensis (23%), the chinoderm Amphioplus megapomus (14%), and the polychaete Tharyx sp. (10%). The overall community structures in the study area showed few seasonal changes, although there was a gradual change in the species composition within each benthic community. Tharyx sp. was the most abundant species in the study area. Because this species has not been found in the other coastal areas except during recent investigations, it is considered to have increased during the course of community succession after the oil spill. The macrozoobenthic around Keumo-do showed little change in species richness, whereas around Sori-do, it showed a few increases in species richness after the summer of 1998. The overall density showed the same trend as species richness. Based on improved community indices, we suggest that the macrozoobenthic communities around Sori-Keumo Islands are gradually recovering from the oil-spill damagecaused by the oil spill.

• Asian Pacific Journal of Cancer Prevention
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• 제17권4호
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• pp.1785-1787
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• 2016

Granular cell tumor (GCT) of the oral cavity is a benign lesion. Half of oral GCTs demonstrate pseudocarcinomatous hyperplasia (PCH) of the mucosa which can mimic invasive islands of oral squamous cell carcinoma (SCC). Such similarity can be confusing when diagnosing or evaluating the two conditions, potentially leading to misdiagnosis or misclassification. Indeed, several misdiagnosed cases of oral GCT have been reported in the literature as OSCC or malignant oral GCT that resulted in unnecessary aggressive treatment for the affected patients. The aim of this study was to investigate if the cytokeratin pattern of the PCH can help in differentiating GCT from oral SCC. To distinguish between these two entities, we examined 12 patient specimens of oral GCT-PCH and oral SCC histologically and via immunohistochemistry (IHC) for CK13, CK17 and P75. The results suggest that the cytokeratin profile of PCH is similar to that of oral SCC. Therefore, consideration of IHC findings for epithelial markers alone may lead to erroneous diagnosis; thus, the presence of the granular tumor underneath the PCH and its immunopositivity for P75 or other neural definition markers can be essential to identify the underlying tumor and exclude oral SCC. Finally we recommend more studies on the molecular biology of PCH to understand how it can mimic oral SCC histologically without harboring its malignant phenotype clinically, which could have significant translational potential for understanding invasive oral SCC.

• Ocean Systems Engineering
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• 제10권1호
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• pp.25-47
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• 2020

A study of the wave conditions for the Asabo offshore location at the Qua Iboe oil field in Eastern Nigeria has been carried out. Statistical analysis was applied to three (3) years of data comprising spectral periods, Tp and significant wave heights, H_s. The data was divided into two (2); data from October to April represents one set of data and data from May to September represents another set of data. The results were compared with similar studies at other locations offshore of West Africa. It was found that there is an absence of direct swellwaves from the Southern Ocean reaching the location under study (the Asabo site). This work suggests that the wave system is largely emanating from the North Atlantic storms. The presence of numerous islands near the Asabo location shields the site from effects of storms from south west and therefore swells from the Southern Ocean. It is noted that the local wind has little or no contribution. An H_s maximum of 2 m is noted at the Asabo offshore location. It is found that the Weibull distribution best describes the wave distribution at Asabo. Thus, the Weibull distribution is suggested to be adequate for long term prediction of extreme waves needed for offshore design and operations at this location.

• 자원환경지질
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• 제14권2호
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• pp.77-91
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• 1981

An airborne magnetometer survey was carried out over an offshore area of about $200,000km^2$ from the southeastern, southern and western part of Korea. Detailed magnetic studies on the geological structure of the southern part of above area ($100,000km^2$) was accomplished. Residual aeromagnetic map was made in order to delineate magnetic provinces, magnetic lineaments and sedimentary basins by application of least square method using computer system. To determine the depth of the sedimentary basins pseudo-gravimetric method was applied. 1. The area studied is divided into four magnetic provinces for the purpose of interpretation on the basis of the magnetic maps. 2. Near shore area and its attached islands of southern part (fiirst and second magnetic province) can be regarded as being the extension from the land geology due to presentation of strong magnetic anomalies and shallow magnetic basements. 3. Magnetic lineament 1-1 is strong magnetic anomalous region which is presumably relevant to volcanic activities in Cretaceous. The depth of magnetic basement of the lineament was determined to 1,500 m. Negative magnetic anomalous zones B1-1 and B1-2 which represent Tertiary basins showed depth of magnetic basement 3 km and 4 km each. The latter can be interpreted as extension of the Taiwan basin which is consisted of Tertiary sediments. 4. Magnetic lineament 2-1 coincide with Rainan-Fukien massif running NE-SW direction. A lineament located in central part of magnetic lineament 2-1 is well connected with extension of Sobacksan anticlinal axis on land. Volcanic rocks in Gyongsang system concentrated along this lineament. 5. The characteristics of magnetic pattern in the southern Yellow sea basin of western part of Jeju island show weaker magnetic anomalies and deeper magnetic basements than first and second magnetic provinces indicating geological structure of this basin seems to be quite different from that of Jeju strait. 6. In southern part of Jeju island, smoother magnetic pattern develope southward. Maximum depth of magnetic basement in sedimentary basins BIV-1 and BIV-2 were determined down to 6,000 m increasing its thickness toward Taiwan up to 11,000 m in the shelf area off Taichung, Taiwan. Judging from the fact that hydrocarbon was founded in the Tertiary sediments of western coastal area of Taiwan, it can be expected that hydrocarbon will be existed in these sedimentary basins of southern part of Jeju island.