• Clean Technology
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• v.24 no.1
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• pp.55-62
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• 2018

The adsorbent used in water-adsorption cooling system utilizing low-temperature heat of below $90^{\circ}C$ is required to exhibit high water uptake capacity at a relative humidity ($P/P_0$) between 0.1 and 0.3. Mesoporous silica (MCM-41) and MOF(MIL-101) exhibit quite large water adsorption capacity under saturated water vapor at $35^{\circ}C$. However, these adsorbents show small water adsorption capacity ($0.027{g_{water}\;g_{ads}}^{-1}$, $0.074{g_{water}\;g_{ads}}^{-1}$, respectively) in the relative humidity ($P/P_0$) range of 0.1 to 0.3. In this study, the surface properties of mesoporous silica and MOF were modified by simple methods to develop an adsorbent having a higher water uptake than the conventional water adsorbents at a relative humidity ($P/P_0$) of 0.1 ~ 0.3. In the case of mesoporous silica (MCM-41) exhibiting mainly water adsorption at $P/P_0=0.5{\sim}0.7$, aluminum species was functionalized on the mesopore walls and then cations existing near the aluminum were exchanged with various cations (e.g., $Na^+$, ${NH_4}^+$, and $(C_2H_5)_4N^+$). In addition, 20 wt% (to total weight of the composites) of hygroscopic inorganic salt ($CaCl_2$) was impregnated on the MCM-41. In the case of the MIL-101 (MOF), 20 wt% of hygroscopic inorganic salt ($CaCl_2$) was impregnated on the MIL-101. The MCM-41 which was ion-exchanged with various cations has main adsorption branch around 0.5 of $P/P_0$ which was slightly shifted with low-pressure direction in comparison with pristine MCM-41. However, tiny increases were observed on the adsorption in the range of $P/P_0$ between 0.1 and 0.3. After salt impregnation on the MCM-41, the adsorption capacity under $P/P_0=0.1{\sim}0.3$ at $35^{\circ}C$ was increased from $0.027{g_{water}\;g_{ads}}^{-1}$ to $0.152{g_{water}\;g_{ads}}^{-1}$. In the case of MIL-101, the amount of water adsorption at $35^{\circ}C$ under $P/P_0=0.1{\sim}0.3$ was increased from $0.074{g_{water}\;g_{ads}}^{-1}$ to $0.330{g_{water}\;g_{ads}}^{-1}$ after the salt impregnation.

• Journal of the Korean GEO-environmental Society
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• v.17 no.3
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• pp.5-12
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• 2016

Stone column is the method that replace soft ground such as weak clay and loose sand with gravel or crushed stone which has relatively high stiffness and low compressive. Stone column increases bearing capacity of the soft ground, reduces settlement, produces ground improvement effect by consolidation drain, and is effective to prevent soil liquefaction in sandy ground during an earthquake. Stone column has been used in many civil works, and has recorded quite a lot of construction achievement internationally, but there is no standardized settlement calculation method yet. Therefore, in this study, the applicability of the existing theoretical equations were evaluated through comparison and analysis to predict a reasonable settlement of the Stone column. Consequently, Hook's law formula was verified to be the most close to numerical analysis.

• Journal of Environmental Health Sciences
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• v.12 no.2
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• pp.75-85
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• 1986

1. 본 調査연구는 1,000가구를 한국의 4대도시인 서울, 부산, 대구, 광주 地域에서 3단계 標本抽出 방법으로 선택하여 이들의 1인1일 Mono Sodium Glutamate(MSG) 섭취량을 包含한 使用實態를 조사한 것이다. 2. 조사결과에 의하면 한국인 1인1일 平均 섭취량은 1.57g이었고, 섭취량의 分布는 1.57g 이하가 전체가구의 62.8%, 1.58~2.57g가 21.5%, 그리고 2.58~3.57g을 섭취하는 가구가 8.7%로 나타났다. 3. 지역별 평균 섭취량은 대구지방이 가장 높았고(2.06g), 이이서 광주(1.80g), 서울(1.55g)및 부산(148g)의 順序로서 전체적으로 지역간에 큰 差異는 없었다.

• The Korean Journal of Soil Zoology
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• v.8 no.1_2
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• pp.13-16
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• 2003

Disposal possibility of raw food wastes which have various characters without any washing and composting process was tested directly using the earthworm, Eisenia andrei. The amount of feeding treatment a day by the earthworm was investigated according to input amount of 1.5 kg/m$^2$ or 3.0 kg/m$^2$ of fifteen food wastes with the different pH and EC. Earthworm disposed an average of 0.87 kg/m$^2$/day of food wastes at the constant temperature of 15$^{\circ}C$ and 1.01 kg/m$^2$/day at 2$0^{\circ}C$. The most disposal among fifteen food wastes was the food waste with pH 5.3 and EC 17.7 as 1.59 kg/m$^2$/day at 15$^{\circ}C$ and as 1.63 kg/m$^2$/day at 2$0^{\circ}C$. The least disposal was the food waste with pH 3.9 and EC 17.7 as 0.31 kg/m$^2$/day at 15$^{\circ}C$ and as 0.53 kg/m$^2$/day at 2$0^{\circ}C$. It took an average 4 days to dispose the amount of 3 kg raw food wastes at 15$^{\circ}C$ and 3.3 days at 2$0^{\circ}C$.

• Journal of Life Science
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• v.8 no.5
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• pp.563-570
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• 1998

The seven (7) housewives were used as subjects at three times per weeks for twelve (12) weeks in order to find out the effects of aerobic exercise and weight training on body composition and blood lipid. Each subject's weight, lean body mass, percent body fat, BMI and blood lipid were measured immediately after the training and the results compared with the same prior to exercises were obtained as follows ; 1. The weight and percent body fat of the subjects were slightly but not significantly decreased, however the lean body mass following training was significantly increased with 1.3 %. BMI S RBW were also not significantly decreased. 2. Calory intake was 1929.9 cal before the training and 1896.0 cal after the training, which doesn't shows much difference. 3. The blood lipid such as TC and LDL-C were a little increased after the training, but HDL-C shows significant increase of 22.7 %, and HDL-C/TC was significantly increased with 13.2 % (p<.05 ) as well. However, TG shows significant decrease (p<.05 ).

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.715-725
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• 2017

Importance of climate change and its impact on agriculture and environment has increased with the rise in the levels of Green House Gases (GHGs) in the atmosphere. To slow down the speed of climate change, numerous efforts have been applied in industrial sectors to reduce GHGs emission and to enhance carbon storage. In the agricultural sector, several types of research have been performed with emphasis on GHGs emission reduction; however, only a few work has been done in understanding the role of carbon sink on reduction in GHGs emission. In this study, we investigated ecosystem carbon balance and soil carbon storage in an agricultural paddy field. The results obtained were as follows: 1) Evaluation of soil C sequestration in paddy field was average $3.88Mg\;CO_2\;ha^{-1}$ following NPK+rice straw compost treatment, average $3.22Mg\;C\;ha^{-1}$ following NPK+hairy vetch treatment, and average $1.97Mg\;CO_2\;ha^{-1}$ following NPK treatment; and 2) Net ecosystem production (NEP) during the paddy growing season was average $14.01Mg\;CO_2\;ha^{-1}$ following NPK+hairy vetch treatment, average $12.60Mg\;CO_2\;ha^{-1}$ following NPK+rice straw compost treatment, and average $11.31Mg\;CO_2\;ha^{-1}$ following NPK treatment. Therefore, it is proposed that organic matter treatment can lead to an increase in soil organic carbon accumulation and carbon sock of crop ecosystem in fields compared to chemical fertilizers.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.667-677
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• 2020

This study was conducted to investigate the fish fauna and characteristics of the Carassius auratus population in the Boryeong Reservoir in Chungcheongnam-do from October 2017 to June 2018. The collected fish were identified as 3,506 individuals of 15 species from a total of nine families. The dominant and subdominant species were H. nipponensis with 1,706 (48.6%) individuals and C. auratus with 1,021 (29.1%) individuals, respectively. The biomass of C. auratus (246,130g), P. fulvidraco(50,610g), C. cuvieri (14,730 g), S. asotus (11,560 g), and C. carpio (10,930 g) was analyzed. The results of the community analysis showed a dominant index value of 0.87 (±0.2), a diversity index value of 0.78 (±0.5), an evenness index value of 0.47 (±0.2), and a richness index value of 0.99 (±0.5). The length-weight analysis of C. auratus showed a regression coefficient b of 3.06, and a condition factor (K) of 0.0004 with a positive slope. The frequency distribution of the total length analysis of the C. auratus population inhabiting the Boryeong Reservoir showed a high distribution of lengths between 140-160 mm and a low distribution between 230-280 mm. The normalized difference water index (NDWI) was analyzed over the Boryeong Reservoir water surface from 2013 to 2014 using Landsat 8 channel data. The areas where the NDWI was decreased were located at the inflow site of Ungcheon Stream.

• Journal of Aquaculture
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• v.18 no.4
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• pp.280-286
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• 2005

Experiments were conducted to examine the differences in ammonia removal rates with the different filter media between sand and zeolite, the expanding rates between $50\%$ and $100\%$, the water temperatures between $15^{\circ}C$ and $25^{\circ}C$, and the ammonia loading rates between 2 mg/L and 5 mg/L in the seawater fluidized bed filters system (FBF). The 2.1 m high FBF (8.3 cm diameter) consisted of the clear acrylic for the upper half and a PVC pipe for the lower half, Sand and zeolite were used as the filter media in sizes of 0.5$\pm$0.1mm. Each biofilter contained 5.4 L of media. The ammonia removal rates of the biofilter were higher at the $25^{\circ}C$ water temperature than those of the biofilter at $15^{\circ}C$ water temperature, and higher at the $50\%$ expanding rate of filter media than those of the biofilter at $100\%$ expanding rate of filter media. Also, the ammonia removal rates of FBF were higher at 5 mg/L ammonia concentration than those of FBF at 2 mg/L ammonia concentration in rearing water. With these better conditions the ammonia removal rates of FBF per day are practically acceptable and ranged ken 80.6 to $210.6g/m^3$.

• Journal of Korean Academy of Nursing
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• v.35 no.5
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• pp.774-786
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• 2005

Purpose: The purpose of this study was to measure home health resource utilization using a Case-Mix Adjustor Model developed in the U.S. Method: The subjects of this study were 484 patients who had received home health care more than 4 visits during a 60-day episode at 31 home health care institutions. Data on the 484 patients had to be merged onto a. 60-day payment segment. Based on the results, the researcher classified home health resource groups (HHRG). Result: The subjects were classified into 34 HHRGs in Korea. Home health resource utilization according to clinical severity was in order of Minimum (C0) < 'Low (Cl) < 'Moderate (C2) < 'High (C3), according to dependency in daily activities was in order of Minimum (F0) < 'High (F3) < 'Medium (F2) < 'Low (Fl) < 'Maximum (F4). Resource utilization by HHRGs was the highest 564,735 won in group C0F0S2 (clinical severity minimum, dependency in daily activity minimum, service utilization moderate), and the lowest 97,000 won in group C2F3S1, so the former was 5.82 times higher than the latter. Conclusion: Resource utilization in home health care has become an issue of concern due to rising costs for home health care. The results suggest the need for more analytical attention on the utilization and expenditures for home care using a Case-Mix Adjustor Model.

• Journal of the Korean Geographical Society
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• v.41 no.5 s.116
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• pp.527-544
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• 2006

This study provides a definition of heat waves, which indicate the conditions of strong sultriness in summer, appropriate to Korea and intends to clarify long term(1973-2006) averaged spatial and temporal patterns of annual frequency of heat waves with respect to their intensity. Based on examination of the Korean mortality rate changes due to increase of apparent temperature under hot and humid summer conditions, three consecutive days with at least $32.5^{\circ}C,\;35.5^{\circ}C,\;38.5^{\circ}C,\;and\;41.5^{\circ}C$ of daily maximum Heat Index are defined as the Hot Spell(HS), the Heat Wave(HW), the Strong Heat Wave(SHW), and the Extreme Heat Wave(EHW), respectively. The annual frequency of all categories of heat waves is relatively low in high-elevated regions or on islands adjacent to seas. In contrast, the maximum annual frequency of heat waves during the study period as well as annual average frequency are highest in interior, low-elevated regions along major rivers in South Korea, particularly during the Changma Break period(between late July and mid-August). There is no obvious increasing or decreasing trend in the annual total frequency of all categories of heat waves for the study period However, the maximum annual frequencies of HS days at each weather station were recorded mainly in the 1970s, while most of maximum frequency records of both the HW and the SHW at individual weather stations were observed in the 1990s. It is also revealed that when heat waves occur in South Korea high humidity as well as high temperature contributes to increasing the heat wave intensity by $4.3-9.5^{\circ}C$. These results provide a useful basis to help develop a heat wave warning system appropriate to Korea.