• Korean Journal of Ecology and Environment
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• v.46 no.4
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• pp.488-498
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• 2013

A three-dimensional hydrodynamic model was applied to the Lake Euiam. The lake has three inflows, of which Gongji Stream has the smallest flow rate and poorest water. The dam-storage volume, watershed area, lake shape and discharge type of the Chuncheon Dam and the Soyang Dam are different. Therefore, it is difficult to analyze the water plume and mixing pattern due to the difference of the two dams regarding the amount of outflow and water temperature. In this study, we analyzed the effects of different characteristics on temperature and conductivity using the model appropriate for the Lake Euiam. We selected an integrated system supporting 3-D time varying modeling (GEMSS) to represent large temporal and spatial variations in hydrodynamics and transport of the Lake Euiam. The model represents the water temperature and hydrodynamics in the lake reasonably well. We examined residence time and spreading patterns of the incoming flows in the lake based on the results of the validated model. The results of the water temperature and conductivity distribution indicated that characteristics of upstream dams greatly influence Lake Euiam. In this study, the three-dimensional time variable water quality model successfully simulated the temporal and spatial variations of the hydrodynamics in the Lake Euiam. The model may be used for efficient water quality management.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.632-637
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• 1996

Effects of refrigeration temperature and its fluctuation range on the growth of psychrotrophic microorganisms and the quality of refrigerated foods such as apple, fish and oyster were evaluated to find optimum storage conditions for a domestic refrigerator. Refrigeration temperature was $2^{\circ}C$ or $4^{\circ}C$, and fluctuation ranges were varied: ${\pm}0.3,\;{\pm}1.0,\;{\pm}1.2,\;or\;{\pm}4.0^{\circ}C$. Changes in hardness of apples stored at $2{\pm}0.3^{\circ}C$ were much slower than those of apples stored at $4{\pm}1.2^{\circ}C$. Freshness of fish and oyster also lasted much longer at low temperature such as $2{\pm}0.3^{\circ}C$. The growth of Listeria monocytogenes inoculated on sliced ham was inhibited for 1 month at $2{\pm}0.3^{\circ}C$, but the cells at $4{\pm}1.2^{\circ}C$ began to grows as time elapsed. Therefore, it was expected that shelf-life of certain food stored in a domestic refrigerator could be extended by lowering temperature to $2^{\circ}C$ and by reducing fluctuation range of refrigerator.

• Journal of Yeungnam Medical Science
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• v.16 no.2
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• pp.208-218
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• 1999

Background: Lung cancer-associated hypercalcemia is one of the most disabling and life-threatening paraneoplastic disorders. Humoral hypercalcemia is responsible for most lung cancer-associated hypercalcemia. Patients with hypercalcemia are usually in the advanced stage with obvious bulky tumor and carry a poor prognosis. Materials and Methods: Total 29 patients satisfied the following criteria: histologically proven primary lung cancer, corrected calcium level ${\geq}$ 10.5 mg/dL, and symptoms which could possibly be attributed to hypercalcemia. In this retrospective study, we evaluated the various clinical aspects of hypercalcemia, in relation to cancer stage, histologic cell type, mass size, bone metastasis, performance status, and other possible characteristics. Results: Total 29 lung cancer patients with hypercalcemia were studied, and most of them had squamous cell carcinoma in their histologic finding. The incidence of hypercalcemia was significantly higher between 50 and 69 years of age, and in the advancement of cancer stage. Although serum calcium level showed positive correlation with mass size, performance status, and bone metastasis, it was not significant statistically. Altered consciousness was significantly more frequent in the patients with higher serum calcium level. There were no differences in effectiveness among therapeutic regimens. Hypercalcemia was more frequently in the later stage of disease than during the initial diagnosis of lung cancer. Most of the patients died within 1 month after development of hypercalcemia. Conclusion: We concluded that hypercalcemia in lung cancer is related to extremely poor prognosis, and may be one of the causes of death and should be treated aggressively to prevent sudden deterioration or death.

• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.263-271
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• 1987

The cyclical trend and seasonal variations of chestnut prices have been analyzed to find out the chestnut price fluctuation in Korea during 1966-1985. The optimum prices, production, and plantation area for the next twenty five years (1986-2010) have been forcasted by the derived equation models. The results of study can be summarized as follows: 1. The chestnut prices were increased by 14.67 percent per annum during 1966-1972, an d decreased by 9.24 percent during 1973-1985, due to the excessive production of chestnut. 2. The chestnut prices showed the lowest price during the harvesting season, especially in October (89.1), and highest in July (109.1). Seasonal fluctuation of chestnut prices were 0.0837 (C.V value) during 1966-1975, and 0.0706 during 1976-1985. Such a seasonal fluctuation of chestnut prices tends to be even with the passage of time. 3. The equation model of predicted chestnut prices was derived as follows : PR=117788.088 - 7.60 TC/Pop + 6.585 GNP/Pop The chestnut prices will be the lowest in 1988, but increased rapidly thereafter. 4. The equation model of optimum chestnut production was derived as follows : $${\ell}n\;PD/Pop=-8.5147-0.8267{\ell}n\;PR+3.3063{\ell}n\;GNP/Pop$$ To maintain optimum chestnut prices according to this model, chestnut production should be 133,000 ton for 1988, and 1,899,000 ton for 2010. 5. Optimum chestnut plantation area will be 4,000 ha in 1988, and thereafter total plantation area will be up to 57,400 ha in 2010.

• Journal of dental hygiene science
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• v.10 no.3
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• pp.147-153
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• 2010

The purpose of this study was to investigate the correlation between food intake pattern body component bone mineral density(BMD) and dental caries experience of college women and we wanted to determine the correlation of these factors with dental caries experience. Research was conducted to offer basic data to develope a nutritional program for the future prevention from oral disease. The subjects in this study were 132 college women who participated in the food intake survey and who's body component and BMD was measured. The statistical analysis was done by using the SPSS 15.0 program. The results of this study were as follows; 1. The food intake pattern was not directly correlated with DMFT index. 2. The body component was not directly correlated with DMFT index. 3. The SOS, BQI was directly correlated with DMFT index(p<0.05). 4. T-score of BMD had the greatest influence on DMFT index(p<0.05). Above results indicated that bone mineral density are related with the incidence of dental caries experience and further research is necessary to develop a nutritional and health promotional program in order to prevent oral illness.

• Geophysics and Geophysical Exploration
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• v.7 no.3
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• pp.164-173
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• 2004

To delineate geothermal water movement at the Pohang geothermal development site, Self-Potential (SP) survey and monitoring were carried out during pumping tests. Before drilling, background SP data have been gathered to figure out overall potential distribution of the site. The pumping test was performed in two separate periods: 24 hours in December 2003 and 72 hours in March 2004. SP monitoring started several days before the pumping tests with a 128-channel automatic recording system. The background SP survey showed a clear positive anomaly at the northern part of the boreholes, which may be interpreted as an up-flow Bone of the deep geothermal water due to electrokinetic potential generated by hydrothermal circulation. The first and second SP monitoring during the pumping tests performed to figure out the fluid flow in the geothermal reservoir but it was not easy to see clear variations of SP due to pumping and pumping stop. Since the area is covered by some 360 m-thick tertiary sediments with very low electrical resistivity (less than 10 ohm-m), the electrokinetic potential due to deep groundwater flow resulted in being seriously attenuated on the surface. However, when we compared the variation of SP with that of groundwater level and temperature of pumping water, we could identify some areas responsible to the pumping. Dominant SP changes are observed in the south-west part of the boreholes during both the preliminary and long-term pumping periods, where 3-D magnetotelluric survey showed low-resistivity anomaly at the depth of $600m\~1,000m$. Overall analysis suggests that there exist hydraulic connection through the southwestern part to the pumping well.

• Food Science and Preservation
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• v.13 no.2
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• pp.144-153
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• 2006

The effects on deacidification of citrus fruits produced at early harvesting season for juice products were examined by heating treatment of raw fruits and electrodialysis of juice. Weight and total acidities were decreased by heating treatment for 40 hr at $25^{\circ}C,\;30^{\circ}C,\;35^{\circ}C\;and\;40^{\circ}C$, but $^{\circ}Brix$ and pH increased Sugar to acid ratio also increased. Total acidities were decreased from 1.25 (Oct30, 2004), 1.24 (Nov.5, 2004), 0.99 (Nov.13, 2004) and 0.98% (Nov.19, 2004) to 0.48 (Oct30, 2004), 0.51 (Nov.05, 2004), 0.37 (Nov.13, 2004) and 0.42% (Nov.19, 2004) by electrodialysis for 100 min respectively, and $^{\circ}Brix$ also slightly decreased, but solid to acid ratio was increased as a result. However pH and color remained almost unchanged by electodialysis. Also, free sugar contents of citrus juice little were changed, but organic acid content were decreased fairly. Narirutin and hesperidin content among flavonoids were slightly decreased by electrodialysis, but they were not significantly different. $K^+,\;PO_4^{2-},\;SO_4^{2-}\;and\;Cl^-$ content were decreased by electrodialysis, and $K^+$ contents decreased by more than 80% However, $Na^+$ consent was increased by about 2 times. Total polyphenol contents and electron donating abilities were decreased a little by electrodialysis but nitrite scavenging abilities were little changed. By acceptability test citrus juice prepared by electrodialysis for 100 min was superior to original citrus juice.

• Journal of Animal Environmental Science
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• v.18 no.3
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• pp.221-228
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• 2012

Physicochemical properties of liquid fertilizer samples of resource organization, which are domestically produced and distributed, are analyzed. Major contents of the research results are as follows. 1. The ratio of complete decomposition for liquid fertilizer is 49% at Public Resource Center and 33% at Liquid Fertilizer Supply Center. The combined ratio of both half-decomposed and un-decomposed liquid fertilizers is over 50% at both centers. 2. The ratio of complete decomposed liquid fertilizer, 67%, is the highest in Gangwon and Gyeonggi-do area. The ratio of un-decomposed liquid fertilizer is high in Chungbuk and Chungnam area. The sum of ratios of the half- and un-decomposed is over 60% in the areas except Gyeonnggi-do and Gangwon-do. 3. As a result of regional comparison of the physicochemical properties of liquid fertilizers, concentration variation in most of the items are large, and the degree of uniformity is found to be considerably low. In particular, concentration variation in T-N and $NH_4$-N is the most noticeable. 4. The items that physicochemically correlated to the degree of decomposition of liquid fertilizer are appeared to be T-N, $NH_4$-N, $NO_3$-N, EC, $SCOD_{Mn}$, and ORP. 5. The physicochemical average values of the liquid fertilizer estimated as "complete decomposed" are appeared to be T-N 829 mg/L,$NH_4$-N 517 mg/L, $NO_3$-N 151 mg/L, $SCOD_{Mn}$ 1,205 mg/L, EC 10.32 mS/cm, ORP -117.12 mV.

• Archives of design research
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• v.17 no.4
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• pp.241-250
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• 2004

In this research, the copper alloy plates C2200, C5210, C7701, C8113 were selected to make datum and to identify further usage of metal craft experimentation. For its experimentation, the general welding and TIG welding methods were researched; for 2nd experimentation, the Reticulation and Electroforming skill's differences in color and temperature were researched. With these methods 3 different kinds of works are introduced for sample studies. For this research, Dr. Lee, Dong-Woo who works in Poongsan Metal Co, supported 4 kinds of copper alloy metals. Which are Commercial bronze (Cu-Zn), Deoxidiged Copper(Cu-Sn-P), Nickel Silver (Cu-Ni-Zn), and White Bronze (Cu-Ni); they were applied partly and wholly by the method of Laminatin, Reticulation, Fusing, and Electroforming skills. In case of C2200, the brass, the A. C. TIG welding method is better under 2mm slight plate; the D.C. TIG welding is better upper 2mm plate; and 250~300$^{\circ}C$ is recommended for remain heat treatment. In case of C5210, not having Hydrogen in high temperature return period, doesn't need Oxygen in high temperature and hardening in comparative high temperature neither, it is good for welding. It contains Sn 2-9% ad P 0.03-0.4% generally; and in accordance with the growth rate of Sn contain amount, the harden temperature boundary become broad. In case of cold moment after welding, they are recommended that higher speed TIG welding, smaller melting site and less than 200$^{\circ}C$ for pre-heating temperature. In case of C7701, the 10-20% Ni, 15-30% Zn are widely used.. If it is upper 30% Zn, it become (${\alpha}+{\beta}$) system and adhesive power rate become lower, and the productivity become lower in low temperature but the productivity become higher in high temperature. Nickel Silver's resistance of electricity is well; and the heatproof and incorrodibility is good, too. Lastly, in case of C8113, good at persistence in salty and grind; high in strength of high temperature. In case of white brass, contain 10-30% Nickel and hardened in high temperature and become single phrase. For these reason, the crystallization particles easily become large, if the resistance become higher small amount of Pb, P, S separation rate become higher.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.61-72
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• 2014

This paper analyzed transition pathways toward a low carbon society in Korea to meet global $2^{\circ}C$ climate target. Lower economic growth, industrial structure change, enhance of energy demand management, decarbonization of power sector, and replacement of low carbon fuel could reduce greenhouse gas (GHG) emission from fuel combustion in 2050 by 67% against in 2011, or by 74% against in BAU (Business-As-Usual). Lower economic growth contributes to 13% of cumulative emission reduction relative to BAU, industrial structure change 9%, enhance of energy demand management 72%, decarbonization of power sector 5% and replacement of low carbon fuel 1% respectively. Final energy consumption in 2050 needs to be reduced to 50% relative to 2011, or to 41% relative to BAU. Nuclear, coal and renewable energy represent 31%, 40%, 2% respectively among electricity generation in 2011, but 38%, 2%, 32% in 2050. CCS represents 23% of total generation in 2050. Emission intensity of electricity in 2050 was decreased to 19% relative to 2011, or to 24% relative to BAU. Primary energy in 2050 was decreased to 64% compared to 2011, or to 44% compared to BAU. Final energy consumption, primary energy supply and GHG emission from fuel combustion from 1990 to 2011 increased by 176%, 197%, 146%. Radical change from historical trend is required to transit toward a low carbon society by 2050. Appropriate economic growth, structural change to non-energy intensive industries, energy technology research, development and deployment (RD&D) in terms of enhancement of energy efficiency and low carbon energy supply technologies, and fuel change to electricity and renewable energy are key instruments.