• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.4
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• pp.421-428
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• 2009

In Korea, the change of river flux due to seasons change is so considerable because of the mountainous terrain with the sharp slope and leaned rainfall. This unfavorable natural condition and the difficulties in precise grasping of the river status made the water resource management difficult so that the necessity of the precise river management has been continuously increased. In this study, a precise river-region DEM using the latest equipments of ALS and MBES is constructed. After acquiring DEM from each senor on the river region, a single DEM was generated by combining them. Also, the field inspection was carried out in the overlapped region of ALS and MBES in order to verify the quality of DEM. The verification of DEM was carried out by comparison between TINs obtained from the combined result of ALS and MBES and the surveying result from total station at more than 10 points in the selected two test areas. As a result, NO.1-area's RMSE of 0.322m and 0.113m are obtained for NO. 1 and NO. 2 areas, respectively. The result of this study shows the feasibility of DEM construction for river region using ALS and MBES as seen in the case of NO. 2 area. At the same time, it was appeared that a better method on the data fusion should be developed as seen in the result of NO. 1 area.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.1
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• pp.9-18
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• 2013

Two-phase vapor-liquid flows exist in many shell and tube heat exchangers such as condensers, evaporators, and nuclear steam generators. To understand the fluid dynamic forces acting on a structure subjected to a two-phase flow, it is essential to obtain detailed information about the characteristics of a two-phase flow. The characteristics of a two-phase flow and the flow parameters were introduced, and then, an experiment was performed to evaluate the pressure loss in the tube bundles and the fluid-dynamic force acting on the cylinder owing to the pressure distribution. A two-phase flow was pre-mixed at the entrance of the test section, and the experiments were undertaken using a normal triangular array of cylinders subjected to a two-phase cross-flow. The pressure loss along the flow direction in the tube bundles was measured to calculate the two-phase friction multiplier, and the multiplier was compared with the analytical value. Furthermore, the circular distributions of the pressure on the cylinders were measured. Based on the distribution and the fundamental theory of two-phase flow, the effects of the void fraction and mass flux per unit area on the pressure coefficient and the drag coefficient were evaluated. The drag coefficient was calculated by integrating the measured pressure on the tube by a numerical method. It was found that for low mass fluxes, the measured two-phase friction multipliers agree well with the analytical results, and good agreement for the effect of the void fraction on the drag coefficients, as calculated by the measured pressure distributions, is shown qualitatively, as compared to the existing experimental results.

• Journal of Haehwa Medicine
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• v.26 no.1
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• pp.33-48
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• 2017

Objective : Ten heavenly stems and twelve earthly branches are the important means to understand the orders of changes in heaven and earth. Method : We have so far looked into detailed explanations about twelve earthly branches in Seolmunhaeja, annotations in Seolmun of four major people, and commentaries in Jeongyeokwonui. Result & Conclusion : This can be also applied to the explanations of twelve early branches, as follows. In the $11^{th}$ month of the lunar calendar, the yang energy is finally born amid full of the ying energy. In the $12^{th}$ month, the yang energy prepares to break through the knots of the ying energy and gets ready to come out of the ground. In the first month, three kinds of the yang energy start to become vigorous and active. In the second month, the yang energy gains more force, sprouting various plants on the ground. In the third month, the yang energy arouse further, strengthening and growing plants. In the fourth month, all the yang energy is released, while the ying energy is still hiding. In the fifth month, one ying energy is born amid full of the yang energy, and there are interchanges between the yang energy and the ying energy. In the sixth month, the yang energy is still strong and vigorous, ripening the fruits in the fields. In the seventh month, the yang energy starts to hurt all creation. In the eighth month, the ying energy starts to flourish, and the yang energy starts to decline, diminishing all creation and, however, still ripening grains to be harvested. In the ninth month, one yang energy starts to hide from sight, not working its duty, while five kinds of the ying energy start to annihilate all creation. Finally, in the tenth month, the small yang energy hides to be rebirthed amid the flux and reflux of the ying-yang energy. The creative and unique interpretation of Jeongyeokwonui about twelve earthly branches is worth to be referred. It is definitely beyond the other existing explanations, as it incorporates trigrams and hexagrams from I Ching (Book of Changes) and the five primary substances.

• Journal of Periodontal and Implant Science
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• v.28 no.2
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• pp.309-320
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• 1998

The periodontal health has been evaluated clinically by various epidemiological indices, and in researches by measurement of gingival crevicular fluid. Laser Doppler flowmetry is a reliable and objective method that allows immediate measurement of erythrocyte flux in approximately one cubic mm of the capillary bed without disturbing the tissues. The purpose of the present study was to determine whether human gingival blood flow was different according to measuring area, measuring time, and sex or not. Forty volunteers with good general and periodontal health, aged early twenties and unmarried, were selected. Laser Doppler flowmetry($floLAB^{(R)}$, Moor Instruments Ltd., England) was applied to measure the gingival blood flow of marginal gingiva, interdental papilla, attached gingiva and alveolar mucosa. The blood flow of interdental papilla was measured at 9-10 AM, 1-2 PM, and 5-6 PM. The difference of blood flow according to measuring area and measuring time was statistically analyzed by one way AOVA and Dunkan test, and the difference of blood flow between men and women was statistically analyzed by t-test. (1) Mean blood flow was significantly higher in alveolar mucosa than in the gingiva(p<0.05), and there was no significant difference in blood flow between marginal gingiva and interdental papilla(p>0.1). (2) Mean blood flow was significantly higher at 5-6 PM than at 9-10 AM and 1-2 PM(p<0.05). But there was no significant difference in gingival blood flow between 9-10 AM and 1-2 PM(p>0.1). (3) There was no significant difference in gingival blood flow between men and women(p>0.1). The above results suggest that the measurment of gingival blood flow using laser Doppler flowmetry may be clinically applicable to early determination of gingival inflammation and evaluation of healing status, but further studies are necessary to standardize and simplify the measuring procedure.

• Journal of Environmental Science International
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• v.3 no.2
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• pp.111-128
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• 1994

The distributions of sea surface temperature across the Cheju Strait and the Korea Strait have been measured by using a thermometer installed on board No.1 Cheju, a ferry that operates regularly between Pusan and Seogwipo. The data from 14 October 1991 to 15 August 1992 were analyzed in this paper. A clear temperature front is wormed at the adjacent sea of Geomundo, and its position is not fixed and moves north and south. The slow northward movement of the front can easily be traced, but the southward movement from March to October is obscure. The temperature contrast in the Cheju Soait and the Korea Strait is very we in this period. Some periodical fluctuations with a period of several tens of days are observed in the region of the temperature front from November to February. This fluctuation seems to be caused by winter heat flux exchange and the strong southeastward wind force. The result shows that continous observation of the sea surface temperature distribution across the Cheju Strait and the Korea Strait yields a good method for monitoring the presence of Tsushima Warm Current and the fluctuations of South Korea Coastal Water. The formation and structure of shelf front in the Cheju Strait and the Korea Strait was analysed based on the detailed oceanographic data observed during the period of 1990-1992. The analysis shows that well-defined fronts were formed through yearly around the Chuja Island, particularly, in summer. In nature, its structure and formation position can be changed easily from year % year and by season. But, in region of the Korea Strait this front is relatively weak.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.1
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• pp.132-138
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• 2015

Trees, cultivated in containers, are appropriate in soil deformation such as road sites with cutting and filling. This study tested the effectiveness of trees produced in containers for early rootage in street tree transplantation. For the study, Korean Mountain Ashes(Sorbus alnifolia) were used for experimental groups. The groups were categorized into three categories: trees cultivated in containers with mulching treatment(group A), trees cultivated outdoors with mulching treatment (group B), and trees cultivated in containers with weeding treatment(group C). Each group consisted of ten trees of the same size and transplanted to the experimental site. In order to compare each group's rootage, the study was carried out with the chlorophyll fluorescence method by the analysis of photochemical reaction. As a result of the study, group B had the lowest the maximum fluorescence amount(P). The amount of fluorescence increased by OJ transition of the process, and appeared to reduce the photosystem II electron transport efficiency. In photosystem II, electron transfer energy flux through photosystem I(RE1o/RC, RE1o/CS) was also reduced by more than 20% in group B. These results may imply that transplantation of container-cultivated trees with mulching treatment provides the most rapid rootage among the groups. The weeding treatment is also more effective than mulching treatment for rapid rootage of street trees.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.2
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• pp.144-150
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• 2013

Hybrid ceramic membrane (HCM) processes that combined ozonation with a ceramic membrane (CM) or a reactive ceramic membrane (RM), an iron oxide nanoparticles (IONs) incorporated-CM were investigated for membrane fouling control. Alumina disc type microfiltration and ultrafiltration membranes doped with IONs by sintering method were tested under varying mass fraction of IONs. Scanning electron microscope (SEM) images showed that IONs were well-doped on the CM surface and doped IONs were approximately 50 nm in size. Change in the pure water permeability of RM was negligible compared to that of CM. These results indicate that IONs incorporation onto CM had little effect on CM performance in terms of the flux. Natural organic matter (NOM) fouling and fouling recovery patterns during HCM processes confirmed that the RM-ozonation process enhanced the destruction of NOM and reduced the extent of fouling more than the CM-ozonation process by hydroxyl radical formation in the presence of IONs on RM. In addition, analyses of NOM in the feed water and the permeate showed that the efficiency of membrane fouling control results from the NOM degradation during HCM processes; leading to removal and transformation of relatively high contents of aromatic, high molecular weight and hydrophobic NOM fractions.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.243-251
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• 2011

BACKGROUND: Gypsum($CaSO_4{\cdot}2H_2O$) is known as an ideal amendment to improve soil quality of the reclaimed coastal land. Since gypsum has very high concentration of electron acceptor like ${SO_4}^{2-}$, its application might be effective on reducing $CH_4$ emission during rice cultivation, but its effect has not been studied well. METHODS AND RESULTS: The effect of gypsum on $CH_4$ emission and rice growth characteristics was studied by pot test, which was packed by reclaimed paddy soils collected from Galsa, Hadong, Gyeongnam province. Chemical-grade gypsum was applied in two soils having EC 2.25 and 9.48 dS/m at rates of 0, 0.5, 1.0 and 2.0%(wt/wt). $CH_4$ emission was characterized a week interval by closed chamber method during rice cultivation. $CH_4$ emission rate was significantly decreased with increasing salt accumulation and gypsum application levels. With increasing gypsum application, dissolved ${SO_4}^{2-}$ concentration in the leachate water was significantly increased, which might have suppressed $CH_4$ production in soil. Total $CH_4$ flux was dramatically decreased with increasing gypsum application. In contrast, rice yield was increased with increasing gypsum application and then achieved maximum productivity at 1.0% gypsum application in two soils. CONCLUSION(s): Gypsum is a very good soil amendment to suppress $CH_4$ emission in reclaimed coastal paddy soils, and improve rice productivity and soil properties. The optimum application level of gypsum is assumed at ca. 1% to improve soil productivity with reducing effectively $CH_4$ emission during rice cultivation.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.52-59
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• 2000

A rapid assay to determine respiration inhibition of Saccharomyces cerevisiae by chemicals was developed. S. cerevisiae was harvested with two different liquid media, yeast extract-peptone-dextrose (YPD) medium capable of occurring both glucose fermentation and mitochondrial respiration, and non-fermentable carbon-yeast extract (NFY) medium capable of occurring respiration only Wells in 96-well plate were loaded with each cell suspension and various concentrations of 46 fungicides with various modes of action. n NFY medium, the non-fermentable carbon source, ethanol (NFY-E medium), glycerol (NFY-G medium) or lactate (NFY-L medium), was used. After incubation for $1{\sim}3$ days, minimum inhibitory concentrations (MICs) of the chemicals were recorded in the media. Of the 46 inhibitors employed in this study, four inhibitors of fungal respiration by blockage of electron flux in the mitochondrial respiratory chain, azoxystrobin, kresoxim-methyl, metominostrobin, and trifloxystrobin, exhibited strong antifungal activity in all of NFY media, but no activity in YPD medium. In contrast to this, five N-trihalomethylthio fungicides showed much stronger antifungal activities in YPD medium than three NFY media. Eleven fungicides inhibited growth of S. cerevisiae in all media and the other 26 fungicides showed no antifungal activity in all media. Thus, our rapid and efficient in vitro method can be considered as an alternative assay system for respiration inhibitor.

• Journal of Navigation and Port Research
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• v.39 no.6
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• pp.485-491
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• 2015

The technology review about risk of hypothermia of victim according to heat transfer characteristic of life raft and sea state can use accident correspondence of standing and sinking of ship. This study studied heat transfer characteristics required for the design of life raft and thermal insulation property analysis and evaluation methods. In addition, it is study for comprehend the risk of hypothermia and suggest analysis result that is experiment of thermal insulation property and body temperature property for decide of prediction the body temperature decline Thermal Analysis apply the finite element analysis method is comprehended the property of heat conductivity, convective effect of sea water and properties changes according to property of insulation material. it measure the heat flux with attach temperature sensor on body in order to comprehend the variation of body temperature with boarding a life raft experiment on a human body. This study validate results by comparing variation of temperature measured from experiment on a body with variation of temperature from finite element analysis model. Also, the criteria of hypothermia was discussed through result of finite element analysis.