• Journal of Korean Society of Coastal and Ocean Engineers
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• v.2 no.2
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• pp.104-111
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• 1990

The water level variation due to the Typhoon around the coast of Pusan in the southern sea of Korea is investigated from the observed tidal record. Water level variations at six stations along the coast are discussed in association with the meteorological data. The characteristics of storm surge at Pusan during Typhoon Thelma in 1987 is analysed using the observed data, and it is performed the numerical simulation of storm surge which includes a inverse barometric effect due to the horizontal distribution of sea sur-face pressure. From the calculation results, the peak value of storm surge in the coast of Pusan was occur-red around the 01：00 July 16th, which is well coincident with the observed water level variation at the Kadukdo. However, the calculated value at the Pusan TBM is inconsistent with the observed one, which is regarded due to a reason that the Tidal Bench Mark (TBM) locates in the channel. In the computation results, the maximum surge occurs at the coast of Nakdong estuary, which is considered primarily due to a topographic effect, and water level variation exceeded 2.5 meter in these areas while only about 60 cm in another coasts.

• Applied Microscopy
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• v.2 no.1
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• pp.17-31
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• 1972

Light and electron microscopic studies were made to investigate the morphological changes in growing galls on the leaf of Lycium chinense MILL caused by Eriophyes kuko Kishda. The results are summarized as follows: 1. Light microscopy At the early stage of the invasion of E. kuko on the back side of the young leaf of L. chinense, the.epidermal cells become hypertrophic and develope a gall. As the gall grows, the cells of both palisade and spongy-layers become hypertrophic and these tissues are hard to be distinguished because of their irregular outgrowth. As the gall grows, the nuclei of the gall also become hypertrophic and larger than these of normal cells. 2. Electron microscopy Under electron microscopy the mitochondria, the golgi apparatus and the plastids of the advanced galls are degenerated and disintergrated and the cell walls become thicker than normal ones. The characteristic star bodies and the ring-form structures are found in the mature gall cells.

• Journal of Plant Biology
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• v.38 no.1
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• pp.79-86
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• 1995

Visible injury symptoms such as necrosis, chlorosis and premature senscence in the leaves of Ginkgo bloba and Pinus thunbergii treated with acid rain of pH 3.2 or below were observed. The epicuticular wax erosions were observed by SEM after exposure to acid rain of pH 2.4 and 3.2 in G. biloba and pH 4.0 below in P. thunbergii. The adaxial epidennal cells and sponge parenchyma cells were compressed, and those were distorted in the leaves of G. biloba treated with simulated acid rain of pH 3.2 or below. However, vascular tissue was intact. With increase of acidity, mesophyll cells were smaller than those of control while intercellular space in mesophyU was increased. In P. thunbergii, sponge parenchyma cells and vascular tissue except epidennis were distorted after exposure to acid rain of pH 2.4. The size change of stomata in foliar injury was not observed, but the stomatal index and size of stomatal aperture in leaves treated with acid rain increased. The stomata of injured leaf were opened in both species examined.amined.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.12 no.1
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• pp.25-30
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• 1976

In the area of the Far East Asia, cyclones are observed 157ea in winter season during the years(1966-1974). Some of them are most difficult to be forecasted due to the extreme irregulalities, have carried out synoptic analysis. The rapid development of cyclones can be attributed to the descending of cold air mass surrounding the axis of the Jet Stream due to the cyclonic rotation, and the lowering of the Jet axis. The Relationships between upper trough line and max. (or min) axis of upper air temperature on the 700mb contributes to the development of the cyclones.

• 한국지구과학회:학술대회논문집
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• 2010.04a
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• pp.70-70
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• 2010

이 연구의 목적은 귀추적 탐구 방법과 관련된 전략들을 적용하여 지구온난화에 관련되어 측정된 다양한 유형의 데이터를 관련된 사실, 원리, 법칙, 선행 연구 결과 등을 토대로 지구통합적인 관점과 지구계를 구성하는 요소들 간의 상호작용과 영향을 중심으로 재해석하고 이해하는 것이다. 지구과학(지구시스템과학)의 학문 성격, 최근 동향, 본성 및 탐구 대상의 특성에 대한 내용과 지구과학의 본질적 속성에 잘 부합하는 귀추적 탐구 방법에 대해 학습한 후, 학생들은 인천 및 다양한 지역의 기상과 해양 자료 분석을 통하여 관찰되는 현상(결과)의 원인과 영향을 파악하는 연구 활동을 하였다. 이 과정에서 귀추적 탐구를 충분히 이해할 수 있도록, 과학 탐구에서 귀추적 탐구 방법을 사용하는 과학자들의 예시와 모의 활동을 통하여, 귀추적 탐구 방법에 사용되는 다양한 사고 전략(예, 데이터의 재구성 전략, 유추 전략, 개념적 결합 전략 등)에 대한 예시를 경험하였다. 학생들은 지구온난화에 관련되어 나타나는 현상(조사된 사항 포함)과 영향에 대해 지구시스템적으로 이해하고 재해석하기 위해 지구시스템을 구성하는 요소(예, 수권, 대기권)와 관련된 데이터 정보를 검색하고 수집하였다. 1) 지구시스템과 지구온난화에 대한 조사하고, 2) 지구온난화 및 기후변화의 변동성 확인한 후, 3) 지구온난화와 관련된 선행 연구 결과 분석하였다. 또한, 지구과학의 본질적 속성에 잘 부합하는 귀추적 탐구 방법의 이해와 적용하는 과정에서 1) 지구 온난화 및 기후 변화의 실태 파악하고, 2) 인천 지역의 월별, 계절별 기온 변화 분석 및 경향 조사(탐색: 연구문제 규명)한 후, 3) 인천과 속초 지역의 기온, 수온의 변화 추이 및 분석 (조사: 원인 조사 과정)하였다. 4) 속초 지역의 평균해면기압변화 추이 및 분석한 후, 그 결과를 토대로 5) 문헌조사 및 선행연구 결과 분석을 통한 지구 온난화의 영향을 미치는 요인 재검토 및 확인(선택 및 설명)하여, 6) 인천지역과 속초지역의 지구온난화 원인 분석 및 문제점 보완(설명)하기 위해 7) 겨울철 지구온난화가 더 심각한지 부산지역과 포항지역의 자료 분석을 통하여 연구 결과 내용의 보완 (추가 조사 및 설명)한 후, 8) 분석 결과 및 해석 내용을 전문가와 상담 실시하였다. 이 연구는 연구를 진행하면서 얻은 결과를 교육적 측면에서 다시 정리해 보면 다음과 같다. 우선, 학생들의 지구환경적 문제 해결 과정에서 귀추적 탐구 방법을 활용한 문제 해결 능력을 향상시켰다. 아울러, 지구과학의 탐구 본성, 최근 동향, 탐구대상의 특성 등의 학습을 통해 지구과학도로서의 기본적인 소양과 자질 향상에 기여하였으며, 사회과학의 연구방법을 순수과학연구에 접목하여 과학자로서의 문제해결 능력과 시스템 사고력을 향상시켰다.

• Journal of Nutrition and Health
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• v.48 no.5
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• pp.381-389
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• 2015

Purpose: The objective of this study was to investigate the effects of a high fructose and fat diet on bone growth and maturation in growing female rats. Methods: Three-week-old female SD rats were randomly assigned to four experimental groups; the control group (CON: fed control diet based on AIN-93G, n = 8); the high-fructose diet group (HFrc: fed control diet with 30% fructose, n = 8); the high-fat diet group (Hfat: fed control diet with 45 kcal% fat, n = 8); and the high-fat diet plus high fructose group (HFrc + HFat: fed diets 45 kcal% fat with 30% fructose, n = 8). Each group was assigned their respective diets for the remaining eight weeks. Bone-related parameters (bone mineral density (BMD) and structural parameters, osteocalcin (OC), deoxypyridinoline (DPD)) and morphologic changes of kidney were analyzed at the end of the experiment. Results: Final body weights and weight gain were higher in the HFat and HFrc + HFat groups and showed higher tendency in the HFrc group compared with those of the CON group (p < 0.05); however, no significant difference in caloric intake was observed among the four experimental groups. The serum OC levels of the HFrc and HFrc + HFat groups were lower than those of the CON and HFat groups (p < 0.05). Urinary levels of DPD did not differ among the experimental groups. BV/TV and Tb.N of trabecular bone were higher in the HFrc + HFat group and showed a higher tendency in the HFrc group than those of the CON and HFat groups (p < 0.05). Tb.Pf of trabecular bone were lower in the HFrc + HFat group than those in the CON and HFat groups (p < 0.05). However, no difference in trabecular BMD was observed among the experimental groups. Cortical bone volume was higher in the HFat and HFrc + HFat groups than in the CON and HFrc groups (p < 0.05). No morphology change in kidney was observed among the experimental groups. Conclusion: Our study suggests that 8 weeks of high-fructose and high fat intake could improve the bone quality (Structural parameters) of trabecular and cortical bone of tibia in growing female rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.11
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• pp.1544-1551
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• 2016

Various types of fermented soybean foods are consumed in various Asian countries, including China, Indonesia, Japan, Korea, and Vietnam. Cheonggukjang is a Korean whole soybean paste fermented by Bacillus subtilis and regarded as a healthy food. The objective of this study was to investigate the Ca-bioavailability and anti-osteoporotic effects of cheonggukjang (CGJ) containing high poly-gamma glutamate (PGA) contents in an animal model. Blood samples were collected from the jugular vein at 0, 0.5, 1, 2, 3, 4, and 5 h after a single oral dose in male rats. Ca-bioavailability in CGJ containing high PGA contents was approximately 3~5 times higher than that of natural CGJ. Female rats were either sham-operated (sham; n=5) or surgically ovariectomized (OVX; five animals per group) and then administered to OVX control, raloxifene hydrochloride (RLX) 1 mg/kg/d, or CGJ containing high contents of PGA (20 and 200 mg/kg/d) for 12 weeks. Serum osteocalcin concentration was significantly lower in the CGJ 200 mg/kg/d group compared with the OVX control group. Serum progesterone concentration was significantly higher in the CGJ 200 mg/kg/d group compared with the OVX control group. Reduction grade of the trabecular bone decreased in the RLX 1 and CGJ 200 mg/kg/d group compared with that of the OVX control group. In conclusion, CGJ 200 mg/kg/d may have inhibitory effects on osteoporosis in OVX rats, and Ca-bioavailability was improved in CGJ containing high PGA contents.

• The korean journal of orthodontics
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• v.26 no.2 s.55
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• pp.153-162
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• 1996

Rapid maxillary expansion is widely used for the correction of anteroposterior discrepancies, constriction of the maxillary arch, etc. This experiment was undertaken to examine the serial changes in the osteogenesis as well as the collagen fiber bundles in the intermaxillary suture during the rapid maxillary expansion treatment. Four young female dogs aged 6 to 8 months old and not showing menarche yet were used for the experiment. The maxillary impression of dogs were taken, expansion device cast and Hyrax screw soldered at the midline in the 1st premolar area. RME device was delivered to the dogs and the activation of 0.25 mm per quarter-turn was done 2 times per day for 10 days until 5 mm separation was made. Separation of the maxilla was confirmed by X-ray. The animals were sacrificed on 0, 15, 30, 60 days from the finish of maxillary separation and preparations for light microscopy and surface electron microscopy were made. The sutures were cut into frontal serial sections for examination of the histological reactions. The following results were obtained and the conclusions made. 1. The edges of the two palatal plates bordering the midpalatal suture which at the beginning of the retention period were mainly composed of compact bone, underwent extensive resorption followed by new bone formation and gradually became spongy bone rich in bone marrow which in the 60 day retention animal became the compact bone with short intermaxillary suture space. During this transformation, newly formed trabecular bone tissues were added to the original margin. 2. Throughout the expansion period, the collagen fibers underwent successive changes such as stretching, loss of polarity, and finally fibrillogenesis. Towards the end of the expansion procedure, sharpey's fiber formation in newly formed bones were observed. 3. Bony spicules were found in the initial stage of retention on occlusal topographic X-rays, which later were confirmed to have ossified. 4. Judging from the histological changes occuring during the experimental expansion, excessive expansion will cause an excessive bleeding, and retard the remodeling of intermaxillary suture. According to the above results, the bone remodeling after rapid maxillary expansion was preceded by the migration of migratory cells into the intermaxillary suture area. The bone remodeling phenomena were on-going during the 2 months retention sample.

• Journal of the Korean Ceramic Society
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• v.41 no.8
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• pp.628-632
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• 2004

A porous hydroxyapatite has been prepared using natural coral which resembles human cancellous bone in microstructure. To obtain a biomaterial having a good biocompatibility, substitution of silicon into the hydroxyapatite framework has been attempted. Si substituted hydroxyapatite has been prepared by hydrothermal treatment and solvothermal treatment of the natural coral repeatedly. Si concentration and phase of the Si substituted hydroxyapatite derived from coral have been characterized using a XRD, ICP, and EDS etc. EDS investigation confirmed the presence of silicon in the framework of hydroxyapatite structure.

• 한국해양학회지
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• v.22 no.4
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• pp.257-270
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• 1987

Fouling communities developing in Jinhae Harbor and Masan Bay were studied by slide and panel immersion test during the period from Dec., 1982 to Nov., 1983. The total viable count of bacteria was estimated more than 1.7${\times}$ 10$\^$4/CFU/$\textrm{cm}^2$ after 15 days of immersion and 46 taxa of benthic diatoms were classified in micro-community. Progressional change of fouling communities was clearly shown and dominant diatom species are Licmophora flavellata, Navicula grevillei, and Nitzschia closterium Major macrofouling organisms are Mytilus edulis, Balanus amphitrite amphitrite, Hydroides ezoensis, and Celleporina sp. Wet weight production of macrofouling organisms exceeds 500g/100cm$\^$2/ after 5months of immersion. Regional defferences in community development are clearly shown in two study areas, and mainly due to the disparities of physicochemical stability and nutritional status of ambient water. Seasonality of larvae and the growth rate are the important factors in fouling community development. Overall process of community development is as follow : bacteria and diatoms-multicellular algae-barnacle, mussels and polychaete-sponge, anemone and ascidian.