• Journal of the korean society of oceanography
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• 제31권4호
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• pp.207-216
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• 1996

A geochemical study of three piston cores (ST.4, ST.6 and ST.20) taken from the Northwest Pacific (eastern edge of Shikoku Basin) provides information about changes in surface water paleoproductivity and sedimentation during the last 127 kys. Paleoproductivity variations were estimated on the basis of total organic carbon content and carbonate mass accumulation rate. The paleoproductivity based on total organic carbon shows significant spatial variations between glacial and interglacial periods. During the last glacial maximum (LGM) paleoproductivity increased about 1.5 times with deglaciation decrease compared with those of the Holocene at inner side of the Shikoku Basin (ST.4 and ST.6). On the other hand, paleoproductivity at outer side of Shikoku Basin (ST.20) indicating not distinctive increase but deglaciation increase. The C/N ratios fall below 10 for cores ST.4 and ST.6, but C/N ratios between 100 ka and 80 ka in ST.20 which show around 10 or larger values suggest a predominance of marine organic carbon with some admixture of terrigenous materials. The carbonate mass accumulation rate of three cores show different patterns of calcareous record with respect to organic carbon based paleoproductivity variation. In the inner side of Shikoku Basin (ST.4 and ST.6) the carbonate mass accumulation rate decreased during last glacial maximum, and significant increase of carbonate mass accumulation rate is recognized at outer side of Shikoku Basin (ST.20). Thus, this set of data reveals that spatial paleoproductivity variations between inner and outer side of Shikoku Basin during the glacial and interglacial periods.

• 한국환경과학회지
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• 제9권5호
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• pp.375-384
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• 2000

It is very important to interprete and simulate the variation of phytoplankton maximum region for the prediction and control of red tide. This study was composed of two parts first the hydrodynamic simulation such as residual current and salinity diffusion and second the ecological simulation such as phytoplankton distribution according to freshwater discharge and pollutant loads. Without the Nakdong river discharge residual current was stagnated in inner side of this estuary and surface distribution of salinity was over 25psu. On the contrary with summer mean discharge freshwater stretched very far outward and some waters flowed into Chinhae Bay through the Kadok channel and low salinity extended over coastal sea and salinity front occurred. From the result of contributed physical process to phytioplankton biomass the accumulation was occurred at the west part of this estuary and the Kadok channel with the Nakdong river discharge. When more increased input discharge the accumulation band was transported to outer side of this estuary. The frequently outbreak of red tide in this area is caused by accumulation of physical processes. The phytoplankton maximum region located inner side of this estuary without the Nakdong river discharge and with mean discharge of winter but it was moved to outer side when mean discharge of the Nakdong river was increased. The variation of input concentration from the land loads was not largely influenced on phytoplankton biomass and location of maximum region. When discharge was increased phytoplankton maximum region was transferred to inner side of the Kadok channel. ON the other hand when discharge was decreased phytoplankton maximum region was transferred to inner side of this estuary and chlorophyll a contents increased to over 20$\mu\textrm{g}$/L Therefore if any other conditions are favorable for growth of phytoplankton. decreas of discharge causes to increase of possibility of red tide outbreak.

• 대한한의학원전학회지
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• 제12권2호
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• pp.166-174
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• 1999

Meridians are often defined as passway of Ki and Blood or something that can control funtions of the body. It is true but I think meridians have something more than that. Meridians are not just passway of Ki and Blood, rather they receive Ki from outside and transform it into Essence-Ki(精氣). If we draw a line in a body, we have Chang-Pu inside and meridians outside. Chang-Pu whim is inside our body hold Essence-Ki and manipulate it. These Chang-Pu also have variation of Ki accumulation-Tai-Yang, Soyang, T'ae$\breve{u}$m, Soum. Nevertheless, their gradients are not great so Ki flow among them are not great either. If there are much Ki flow in our body there will be much Ki consumption resulting in exhaustion of Essence-Ki, which is very hard to acquire. Therefore Chang-Pu keeps less gradient by not moving Ki a lot to preserve Essence-Ki. Chang-Pu, inside, are suitable for storing Ki while meridians, outside, are for producing Ki. Meridinas have great difference in Ki accumulation so there are great flow of Ki. This nature is suitable for producing Ki. For example, roots and limbs of a tree don't have much gradient in Ki. They are concentrated and their shape are not very distinct. On the other hand, leaves are wide and it's easy to tell front from back. It means their Ki gradient is great and their Ki flow is also great. Therefore they suitable for producing Ki. Just like this, meridians in our body are suitable for producing Ki. Areas that meridians cover are much wider than that of Chang-Pu. Four limbs and surface of our body are very distinctive. Ulnar side is high in Ki accumulation but is small in volume so it's better to store Ki there. Radial side is low in Ki accumulation but big in volume so it's better to receive and consume Ki there. Meridians are deeply involved in producing and storing Ki.

• Ocean and Polar Research
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• 제38권2호
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• pp.139-148
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• 2016

The activity concentrations of $^{210}Po$ and $^{210}Pb$ within phytoplankton-zooplankton-anchovy-mackerel in the coastal water of the Jeju Island were determined to understand their distribution and bio-accumulation along the trophic level. In the surface water, the total activity concentrations of $^{210}Po$ and $^{210}Pb$ were $0.83{\pm}0.004mBq\;kg^{-1}$ and $1.27{\pm}0.03mBq\;kg^{-1}$. And the dissolved activity concentration of $^{210}Po$ and $^{210}Pb$ were $0.75{\pm}0.06mBq\;kg^{-1}$ and $1.22{\pm}0.09mBq\;kg^{-1}$ respectively. In the phytoplankton, the concentration factor (CF) of $^{210}Po$ and $^{210}Pb$ were $1.5{\times}10^5$ and $2.6{\times}10^4$ shows $^{210}Po$ is 5 times higher compared to $^{210}Pb$. The similar CF factor in the zooplankton of $^{210}Po$ was derived as $1.4{\times}10^5$. The CF of $^{210}Po$ in anchovy was increased twice compared to that in plankton. This is the evidence that there is $^{210}Po$ bio-magnification in the trophic level of plankton-anchovy. However the $^{210}Po$ activity concentration in the muscle tissue of mackerel was one-hundred times lower than that in anchovy. This reflects that in the trophic level of anchovy-mackerel, the bio-accumulation of $^{210}Po$ is decreased. The activity concentrations of $^{210}Po$ in the internal organs of anchovy and mackerel were 8 to 38 times higher than those in muscle tissues. In phytoplankton-zooplankton-anchovy, the CF of $^{210}Pb$ was decreased five times along the trophic level in order. In anchovy-mackerel it was decreased by 30-70%.

• 항공우주시스템공학회지
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• 제11권5호
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• pp.1-5
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• 2017

본 논문은 실 궤도면 누적량 계산법을 활용한 원자산소의 저궤도위성의 태양전지판 코팅재료 침식량에 대한 예측 연구로써, 기존 프로젝트에서 활용하던 최악 경우 추정법과 상호 비교를 통해 원자산소 영향성의 차이가 있음을 확인하였으며, 이렇게 예측된 결과를 바탕으로 해외 제작사의 설계입증 자료 확인시 활용할 예정이다. 가상으로 설정한 궤도정보를 바탕으로 한 계산은 유럽우주기구(ESA)가 제공하고 있는 우주환경정보시스템을 이용하였고, 실제 궤도상에서의 태양전지판에 충돌되는 원자산소 플럭스를 계산하기 위해서 궤도 계산 소프트웨어를 활용하였다.

• 한국어병학회지
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• 제17권1호
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• pp.21-28
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• 2004

양식 미꾸라지 (Misgurnus mizolepis)가 수중으로 잠입하지 못하고 양어지의 물표면에 배를 위로 한 채 힘없이 회전 유영을 하는 질병이 발생하였다. 병어는 복부가 팽만되어 있었으며, 해부하여 보면 소화관에 커다란 공기방울의 축적, 장염이 현저하였다. 병어를 혈액학적으로 조사한 결과 적혈구수, Ht치 및 Hb 농도는 건강어와 차이가 없었다. 병리조직학적으로는 아가미의 호흡상피의 증생과 새변의 유착, 소화관 상피세포의 출혈, 괴사 및 박리가 관찰되었다. 뒷지느러미와 항문사이를 실로 결박하여 항문으로부터 공기의 배출을 억제한 재현 실험에서 발병어와 같은 증상이 재현되었다. 따라서 이 병은 빠른 성장을 목적으로 고단백질 사료를 투여함으로서 장호흡을 위하여 마신 공기가 소화관내에 축적되고, 축적된 공기의 부력 때문에 물속으로 하강하지 못하게 되고, 또 소화관을 압박하여 소화관에 순환장애를 일으킨 결과 폐사한 것으로 추정된다.

• Design & Manufacturing
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• 제8권2호
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• pp.12-17
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• 2014

Currently, injection molding process is a very useful technique that be applied to many field. And injection molding technology has been commercial based on many studies. However, there is no standard of surface roughness because there are few studies about surface technology of injection product. In addition, when designing the mold, changes of the core surface and the injection conditions are not considered. In this paper, change of surface according to the core and the injection conditions was compared with the surface of the injection product. Accumulation of these technologies will propose direction in mold design, manufacturing and injection molding technology.

• Journal of Periodontal and Implant Science
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• 제35권3호
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• pp.799-811
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• 2005

This study was carried out to examine the potency of the three surface compo- nents from Porphyromonas gingivalis to stimulate the murine macrophage cell line RAW264.7 to synthesize the pro-inflammatory cytokine tumor necrosis factor alpha($TNF-{\alpha}$) and nitric oxide (NO). Lipopolysaccharide(LPS). lipid A-associated proteins(LAP) and saline-extractable surface -associated material(SAM) were isolated from P. gingivalis 381. $TNF-{\alpha}$ release into culture supernatants was determined by two-site ELISA. NO production was assayed by measuring the accumulation of nitrite in culture supernatants. Western blot analysis of iNOS and analysis of reverse transcription(RT)-PCR products were carried out. The surface components extracted from this bacterium were almost equally potent in stimulating release of $TNF-{\alpha}$ and NO by RAW264.7 cells. $TNF-{\alpha}$ that was being measured immunologically was due to activation of $TNF-{\alpha}$ gene transcription. The present study clearly shows that P. gingivalis surface components fully induced iNOS expression in RAW264.7 cells in the absence of other stimuli. The ability of P. gingivalis surface components to promote the production of $TNF-{\alpha}$ and NO may be important in the pathogenesis of inflammatory periodontal disease.

• 한국조경학회지
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• 제33권2호
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• pp.60-70
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• 2005

This study was carried out to elucidate the vertical characteristics of soil properties at six planted sites of land reclaimed from the sea, in Gwangyang Bay, Jeollanam-do Province, Korea. Based on the types of planting site, the chemical properties of the vertical soil layers varied. The vertical variation was great in the planting sites $Z_1\;and\;Z_2$, but less varied in the mounded planting sites $Z_3,\;Z_5,\;and\;Z_6$. Major reasons for the vertical variation in soil chemical properties included differences in the accumulation of organic matter, soil disturbance by heavy construction equipment, and heterogeneity of soil properties between soil horizons. As soil depths increased, soil salts varied. The electrical conductivity (ECe) increased in the lower areas of planting sites $Z_1\;and\;Z_2$, and the disturbed, saline planting site $Z_3$, but decreased in the lower areas of $Z_3,\;Z_5,\;and\;Z_6$. These tendencies did not coincided with exchange cation concentrations $(Na^+,\;K^+,\;Mg^{++},\;Ca^{++})$. Both total carbon (T-C) and total nitrogen (T-N) accumulated more in the lower areas of planting sites than in the higher areas, and levels were higher closer to the surface than in the soil depths. It is supposed that these tendencies are related to the accumulation of fallen leaves or other organic matter at the soil surface, and the soil chemicals then slowly move downward from the surface. Impediments to tree growth included soil hardiness, high soil salinity and exchangeable cation concentration, low soil moisture content, acidic or alkaline soil, low organic matter, heterogeneity of soil texture and establishment of soil stratification.

• 자원환경지질
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• 제30권4호
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• pp.341-352
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• 1997

Retention ponds have been dug along some of the motorways in France to minimize environmental pollution by keeping pollutants from spreading over the surrounding area. In order to study heavy metal pollution and diagenetic behaviour of sediments, eight core samples were collected from the bottom of a retention pond located along the A-71 motorway in Sologne. The metal concentrations in interstitial waters and extractable metal concentrations in sediment layers using sequential chemical extraction method were determined. The depth distributions of Pb, Zn and Cd concentrations in interstitial water and particulate sediments were studied, and distribution coefficients (KD) were also determined to investigate the environmental mobility of these elements. In addition. the index of geoaccumulation and the Fe-normalized enrichment factor were calculated to differentiate the natural accumulation from the anthropogenic pollution. The vertical concentration profiles of heavy metals in core sediments indicate that surface enrichments (0~2 cm) of Pb, Zn, Cd and organic carbon were always observed at each core sample, due to the early diagenesis. However, the major factor contributing to the accumulation of Cd at the sediment surface is attributed to the dissolution of Cd from polluted roadside soil during periods of rainstorms and its subsequent redeposition on the sediment surface after being carried to the retention pond. A comparison of the KD values indiactes that a decrease in the KD values for Pb and Zn was observed with depth while KD values for Cd increase. According to the KD values. the relative mobility of studied metals was determined as following: Mn>Zn>Cd>Pb, for the upper layer, and Mn>Cd>Zn>Pb, for the lower layers.