• Journal of the Korean earth science society
• /
• v.23 no.7
• /
• pp.552-564
• /
• 2002

The data of satellite-observed Microwave Sounding Unit (MSU) channel 1 (Ch1) brightness temperature and General Circulation Model (GCM) reanalyses over the globe have been used to investigate low tropospheric hydrometeors and microwave surface emissivity during the period from January 1981 to December 1993. The average of GCM Ch1 temperature has been reconstructed from three kinds of reanalyses, based on the MSU weighting function. Since the GCM temperature mainly corresponds to the thermal state of the lower troposphere without the difference in the emissivity between ocean and land, it is higher in summer than in other seasons over the regions. The MSU temperature over the ocean shows its maximum at the ITCZ and the SPCZ due to hydrometeors. Over high latitude ocean, the temperature is enhanced because of sea ice emissivity, while it is reduced over the land. The seasonal displacement of the ITCZ and the SPCZ systematically appeared in the difference of Ch1 temperature between the GCM and the MSU. The difference values decrease in the regions of the ITCZ, the SPCZ, and the sea ice because of the increase of the MSU temperature. According to the local minima of the values, the ITCZ moves norhward to 9 N in fall, and the SPCZ moves southward to 12 S in boreal fall and winter. The sea ice in the northern hemisphere is extended southward to 53 N in winter, while the ice in the southern hemisphere, northward to 58 S in boreal summer. We also have discussed the separated contribution from hydrometeors and surface emissivity to the MSU Ch1 temperature, utilizing radiative transfer theory. The increase of 4-6K in the temperature over the ITCZ is inferred to result from hydrometeors of 1-1.5mm/day, and furthermore the increase of 10-30K over the high latitude ocean, ice emissivity of 0.6-0.9.

• Journal of Korean Society of Environmental Engineers
• /
• v.29 no.3
• /
• pp.348-356
• /
• 2007

Statistical and probabilistic method was used in the analysis of data, which is the most effective one in describing the various natures, and the methodology relating the results with the design was developed. Influents and effluents of three treatment plants were analyzed and the focus was made on BOD, COD, SS, IN, TP The fluctuations of influent such as BOD, COD, SS were extremely large and their standard deviations(st.dev) were more than 10 mg/L. but those of TN, TP were small; the st.dev was 6.6 mg/L for TN, 0.6 mg/L for TP, respectively. But, effluent concentration showed consistent pattern regardless of the influent fluctuations, the st.dev was ranged between 0.28 and 4.48 mg/L. Effluent distributional characteristics were as follows; BOD, COD were distributed normally, but SS, TN, and TP, log-normally; unsymmetric and skewed to the right. The coefficient of reliability(COR) based on the results of statistics of data was introduced to evaluate the process performance an4 to reflect the process performance to the process design. The coefficient of reliability relates the design value(the goal) with the standards and it can be used in operating treatment facilities under a certain reliability level and/or in evaluating the reliability of the treatment facilities on operation. Each treated water quality of effluent showed the half of water quality standards in the level of 50% percentile and all treatment plant was achieved 100% probability of water quality standards. It was concluded that the variability of the process performance should be reflected to the design procedure and the standards through the analysis based on the statistics and the probability.

• Economic and Environmental Geology
• /
• v.37 no.1
• /
• pp.61-72
• /
• 2004

The soil samples were collected from the paddy field near the mine tailing dumps in the abandoned Duckum mine in Korea. In the laboratory, the soil solution was extracted from the soil using centrifuge, and analysed for the chemical composition. Physical and chemical soil properties were also analysed. Kaolinite is the main clay minerals in the paddy soil and the CEC value is therefore relatively low. Nearly all soil samples show enrichment in their trace elemental concentrations(Cd, Cu, Pb and Zn) compared with natural background level. Some soil samples exceed the soil remediation intervention values for Cd, Pb and Zn and target value for Cu, when compared with Dutch standard, whereas As, Ni and Cr are in normal range. Lead concentrations in some samples near the mine tailing dumps also exceed the standard for remediation act for agricultural area set by Korean soil conservation law. The trace elemental concentrations are higher in the paddy soil nearer the mine tailing dumps and lower for the samples from distance. Similar trend with distance is found for the soil solution chemistry but the decrease with distance from the mine tailing dumps are sharper than the changes in soil chemistry. Cadmium, Cu and Pb concentrations in the soil solution are very low, ranging from a tenth and hundredths to a maximum of several mg/l, whereas their concentrations in soils are highly enriched for natural background. Most of the trace elements are thought to be either removed by reduced iron sulphides or iron oxides, depending on the redox changes. Geochemical equilibrium modelling indicate the presence of solubility controlling solid phases for Cd and Pb, whereas Zn and Cu might have been controlled by adsorption/desorption processes. Although pollutants migration through solution phase are thought to be limited by adsorption onto various Fe, Mn solid phases, the pollutants exist as easily releasable fractions such as exchangeable site. In this case, the paddy soil would act as pollutant pool, which will supply to plants in situ. whenever the geochemical conditions favour.

• Economic and Environmental Geology
• /
• v.38 no.6 s.175
• /
• pp.717-729
• /
• 2005

Peak cooling load of large buildings is generally greater than their peak heating load. Internal and solar heat gains are used fur selection of adquate equipment in large building in cold winter climate like Canada and even Korea. The cost of geothermal heat exchanger to meet the cooling loads can increase the initial cost of ground source heat pump system to the extend less costly conventional system often chosen. Thermal ice storage system has been used for many years in Korea to reduce chiller capacity and shift Peak electrical time and demand. A distribution system designed to take advantage of heat extracted from the ice, and use of geothermal loop (geothermal heat exchanger) to heat as an alternate heat source and sink is well known to provide many benifits. The use of thermal energy storage (TES) reduces the heat pump capacity and peak cooling load needed in large building by as much as 40 to $60\%$ with less mechanical equipment and less space for mechanical room. Additionally TES can reduce the size and cost of the geothermal loop by 1/3 to 1/4 compared to ground coupled heat pump system that is designed to meet the peak heating and cooling load and also can eliminate difficuties of geothermal loop installation such as space requirements and thermal conditions of soil and rock at the urban area.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.11 no.4
• /
• pp.236-243
• /
• 1991

A field experiment was conducted during the growing season of 1985 to determine the effects of slope orientation, north and south facing exposures and three different altitudes, 800, 1,000 and 1,200m a.s.1. on the dry matter yield, forage quality and botanical composition of alpine pasture. 1. Total dry matter yield of alpine pasture was influenced by slope orientation and altitude. An average forage yield of both exposures at 1,000m a.s.1. was 9,301kg/ha compared with 10,274kg/ha at 800m a.s.1. and the productivity express in relative percentage decreased by 9.5% per 200m attitudinal increase. 2. An average forage yield of both altitudes, 800 and 1,000m a.s.1. on the south facing exposure was 21.5% higher than that on the north exposure. 3. Crude protein concentration of forage grown on both exposures was lowest at 800m a.s.1. increasing gradually as the altitude increased, but crude fiber concentration decreaced in a manner opposite to that of crude protein. 4. Forage grown on the north facing exposure had a higher concentration of crude protein than that grown on the south facing exposure at the same altitude, but lower concentraion of crude fiber. 5. Orchardgrass and timothy were two main species on both exposures at 800m a.s.1. but timothy was only dominant species at 1,000 and 1,200m a.s.1. and performed well up to 1,200m a.s.1. in alpine area. The economic production limit of orchardgrass would be about 800m a.s.1. in the alpine pasture. 6. No soil property differences were found between the north and south facing exposures as well as three different altitudes in the alpine pasture. It seemed that the previous pasture fertilization of the experimental field completely overshadowed any soil property differences from slope orientation and altitude.

• Journal of the Korean earth science society
• /
• v.28 no.3
• /
• pp.298-310
• /
• 2007

Intercomparison between eight radiative transfer codes used for the studies of COMS (Communications, Ocean, and Meteorological Satellite) in Korea was performed under pure molecular, i.e., Rayleigh atmospheres in four shortwave fluxes: 1) direct solar irradiance at the surface, 2) diffuse irradiance at the surface, 3) diffuse upward flux at the surface, and 4) diffuse upward flux at the top of the atmosphere. The result (hereafter called the H15) from Halthore et al.'s study (2005) which intercompared and averaged 15 codes was used as a benchmark to examine the COMS models. Uncertainty of the seven COMS models except STREAMER was ${\pm}4%$ with respect to the H15, comparable with ${\pm}3%$ of Halthore et al.'s (2005). The uncertainty increased under a large $SZA=75^{\circ}$. The SBDART model generally agreed with the H15 better than the 6S model, but both models in the shortwave infrared region were equally good. The direct solar irradiance fluxes at the surface, computed by the SBDARTs of four different users, were different showing a relative error of 1.4% $(12.1Wm^{-2})$. This reason was partially due to differently installing the wavelength resolution in the flux integration. This study may be useful for selecting the optimum model in the shortwave region.

• Journal of the Korean earth science society
• /
• v.39 no.1
• /
• pp.53-66
• /
• 2018

The information of surface reflectance ($R_{sfc}$) is important for the heat balance and the environmental/climate monitoring. The $R_{sfc}$ sensitivity to error-induced variables for the Geostationary Environment Monitoring Spectrometer (GEMS) retrieval from geostationary-orbit satellite observations at 300-500 nm was investigated, utilizing polar-orbit satellite data of the MODerate resolution Imaging Spectroradiometer (MODIS) and Ozone Mapping Instrument (OMI), and the radiative transfer model (RTM) experiment. The variables in this study can be cloud, Rayleigh-scattering, aerosol, ozone and surface type. The cloud detection in high-resolution MODIS pixels ($1km{\times}1km$) was compared with that in GEMS-scale pixels ($8km{\times}7km$). The GEMS detection was consistent (~79%) with the MODIS result. However, the detection probability in partially-cloudy (${\leq}40%$) GEMS pixels decreased due to other effects (i.e., aerosol and surface type). The Rayleigh-scattering effect in RGB images was noticeable over ocean, based on the RTM calculation. The reflectance at top of atmosphere ($R_{toa}$) increased with aerosol amounts in case of $R_{sfc}$<0.2, but decreased in $R_{sfc}{\geq}0.2$. The $R_{sfc}$ errors due to the aerosol increased with wavelength in the UV, but were constant or slightly decreased in the visible. The ozone absorption was most sensitive at 328 nm in the UV region (328-354 nm). The $R_{sfc}$ error was +0.1 because of negative total ozone anomaly (-100 DU) under the condition of $R_{sfc}=0.15$. This study can be useful to estimate $R_{sfc}$ uncertainties in the GEMS retrieval.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.24 no.5
• /
• pp.744-751
• /
• 1995

Effect of licorice root(Glycyrrhiza Uralensis Fischer) on the Dongchimi(watery radish kimchi) fermentation was investigated by measuring physicochemical, microbiological and sensory properties during fermentation up to 41 days. Dongchimi with the various levels(0, 0.5, 1.0, 1.5%) of licorice root was fermented at two temperatures : Group A was fermented at $10^{\circ}C$ and group B was fermented at $4^{\circ}C$ after keeping at room temperature($16{\pm}0.5^{\circ}C$) for 24 hours. During the fermentatiion, pH was slowly lowered in all Dongchimi samples and pH of Dongchimi added licorice root was a little higher than that of Dongchimi without licorice root. Total acidity of group A was slightly larger than that of group B and Dongchimi added licorice root showed small content than that of Dongchimi without licorice root. Reducing sugar content was reached maximum value in 13 days of fermentation in Dongchimi added licorice root of group A and B, group A decreased remarkably in 32 days of fermentation in all samples and group B was maintained in the rest sample except for Dongchimi without licorice root and Dongchimi added 1.5% licorice root. Total vitamin C of Dongchimi added licorice root was slightly higher than that of Dongchimi without licorice root of two groups. Lightness lowered gradually with the fermentation and Dongchimi without licorice root decreased a little than that of Dongchimi added licorice root. The number of lactic acid bacteria in Dongchimi added licorice root was more numerous than that of Dongchimi without licorice root. As a result of the sensory evaluation, group B showed higher scores than group A and Dongchimi added 0.5% licorice root was the most preferable one.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.31 no.5
• /
• pp.871-876
• /
• 2002

This study was conducted to verify the relation between relation between vegetarian diet and the serum lipid levels, blood sugar and blood pressure from October 1996 to February 1997. The vegetarians subjects were 245 Buddhist nuns (age:23～79 yrs) and control subjects consisted of 235 healthy female adults (age: 23～70 yrs) selected from the teachers, the nurses and the housekeepers living in Chinju Gyeongsang Nam-do. The contents included anthropometric measurement, questionnaires about eating behavior score and preference for taste and biochemical characteristics of the blood. The results were summarized as follows. The average duration of vegetarian diet of the vegetarians was 13.1 years. Vegetarians prefer to a pepper, a sweet and a acidic in the right order but that non-vegetarians prefer to a sweet, a acidic and pepper in the right order. Both groups of less than a decade and more than two decade of vegetarian diet prefer to a pepper, sweet, a acidic, a bitter, a salty and a lily, and a 10～20 yr group with vegetarian diet was fond of a pepper, a bitter, a acidic, a sweet, and a oily, in the right order. This seems to be ascribable to a difference in the health knowledge and interest. Vegetarians and non-vegetarians who said that they were fond of salty were 38.8% and 52.8%, medium was 33.9% and 33.6%, and not salty was 27.3% and 13.6%. Eating behavior score of vegetarians and non-vegetarians were 25.1 and 23.1 respectively. Eating behavior scores of vegetarians were significantly higher than those of non-vegetarians (p<0.05). Eating behavior scores of the group with more than a decade of vegetarian diet were significantly higher than those of the group with less than a decade of vegetarian diet. Levels of serum total-cholesterol, LDL-cholesterol, and AI of the salty group were significantly higher (p<0.05) than those of not salty group. Levels of serum triglyceride, HDL-cholesterol, blood sugar had no significant relation with preference of salty. Blood pressure was not related with preference of salty, but that of those who prefer a salty tended to be high. This study also reveals that the preference of a salty was significant influence on serum total-cholesterol, LDL-cholesterol, and AI, but the vegetarians did not prefer salty and have a good eating behavior. Consequently, vegetarian diet can be considerably effective in reducing the level of the risk factors of cardiovascular disease.

• The korean journal of orthodontics
• /
• v.39 no.4
• /
• pp.213-224
• /
• 2009

Objective: The aim of this study was to find out whether Er:YAG laser can aid in debonding ceramic brackets, and to see what kind of method will be the most appropriate for debonding. Methods: One hundred and ninety teeth, monocrystalline brackets ($MISO^{TM}$, HT, Ansan-Si, Korea), polycrystalline brackets ($Transcend^{TM}$ series 6000, 3M Untek, Monrovia, CA, USA) and the KEY Laser3 (KavoDental, Biberach, Germany) were used. Experimental groups were classified according to the type of ceramic brackets, and the amount of laser energy (0, 140, 300, 450, 600 mJ). After applying laser on the bracket at two points at 1 pulse each, the shear bond strength was measured. The effect of heat caused by laser was measured at the enamel beneath the bracket and pulp chamber. After measuring the shear bond strength, adhesive residue was evaluated and enamel surface was investigated using SEM. Results: All ceramic bracket groups showed a significant decrease in shear bond strength as the laser energy increased. The greatest average temperature change was $3.78^{\circ}C$ on the enamel beneath the bracket and $0.9^{\circ}C$ on the pulp chamber. Through SEM, crater shape holes caused by the laser was seen on the enamel and adhesive surfaces. Conclusions: If laser is applied on ceramic brackets for debonding, 300 - 450 mJ of laser energy will be safe and efficient for monocrystalline brackets ($MISO^{TM}$), and about 450 mJ for polycrystalline brackets ($Transcend^{TM}$ series 6000).