• Journal of radiological science and technology
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• v.30 no.4
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• pp.381-389
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• 2007

The purpose of this study is investigation of radiation dose in CT scan. Data were collected from various references and organizations. Doses measured by CT scanners of each medical organization were analyzed and they were calculated through the examination protocol. The results are as follows : 1. $CTDI_W$ value per 100mAs measured by Head Phantom was the highest in <4-slice MDCT scanner> of 24.20 mGy. $CTDI_W$ values were significantly different among scanner generations(p < 0.01). 2. $CTDI_W$ value per 100 mAs measured using body phantom was the highest in <4-slice MDCT scanner> of 13.58 mGy and the $CTDI_W$ values were significantly different among scanner generations(p < 0.01). 3. When contrast medium was not used, the highest scanner was <16 slice MDCT> of $818.83\;mGy{\codt}cm$ in exposure dose in brain scan(p < 0.05). When the contrast medium was used, the highest scanner was <4 slice MDCT> and its average was $1,460.77\;mGy{\cdot}cm$(p < 0.1). 4. When the contrast medium was not used, the highest scanner was <16-slice MDCT> of $521.63\;mGy{\cdot}cm$ on average in terms of the exposure dose in chest inspection(p<0.05). when the contrast medium was used, the highest scanner was found in 8 slice MDCT scanner and its average was $1,174.70\;mGy{\cdot}cm$. There was no statistically significant difference among scanners. 5. When the contrast medium was not used, the highest scanner was <16-slice MDCT> and its average was $856.27\;mGy{\cdot}cm$ in exposure dose on the abdomen-pelvis(p<0.05). when the contrast medium was used, the highest scanner was <16-slice MDCT> and its average was $1,720.64\;mGy{\cdot}cm$ on average (p < 0.05). 6. When the contrast medium was not used, the highest scanner was <8-slice MDCT> and its average was $612.07\;mGy{\cdot}cm$ in exposure dose in liver inspection(p < 0.05). when the contrast medium was used, the highest scanner was <8-slice MDCT scanner> and its average was $2,197.93\;mGy{\cdot}cm$ in exposure dose(p < 0.1). seventy six point two percent of medical facilities were in risk of radiation exposure while the number of phase was three to four times in their dose inspection of contrast medium.

• The Korean Journal of Malacology
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• v.29 no.4
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• pp.263-272
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• 2013

The development of swift's scallop Chlamys swiftii, reared in the laboratory, has been examined through the investigation of morphological characteristics in fertilized egg, larvae and juvenile. Eggs were fertilized with a dilute sperm solution to improve the survival of fertilized eggs. Developing larvae were maintained at a temperature of $16{\pm}0.5^{\circ}C$ and salinity concentration of 33 ppt. We have investigated the fertilization rates and egg number spawned at several stimulating conditions such as sunlight exposure, air dry, seawater temperature rise ($5^{\circ}C$) and seawater temperature rise ($5^{\circ}C$) after exposure of air dry for spawning induction of swift's scallop Chamys swiftii. Stimulation treated with sunlight exposure and seawater temperature rise ($5^{\circ}C$) have shown the spawning number of 700,000-900,000 and 700,000-800,000 per individual, respectively while stimulation treated with seawater temperature rise ($5^{\circ}C$) after exposure of air dry have shown the high spawning number of 1,000,000-1,500,000 per individual. Survival rate of D-shaped larvae of swift's scallop put into the different seawater temperatures of $8^{\circ}C$, $12^{\circ}C$, $16^{\circ}C$, $20^{\circ}C$ and $24^{\circ}C$ has been 4.1%, 11.6%, 32.7%, 18.6% and 3.2%, respectively. Fertilized eggs with the diameter of $72{\mu}m$ developed into trochophore larvae of $103{\pm}3.8{\mu}m$ shortly after 35 hours and to D larvae of $129{\pm}10.4{\mu}m$ shell length within 72 hours. It took 336 hours to become initial Umbo-stage larva of $145{\pm}16.8{\mu}m$ shell length. Post larvae, which have been $197{\pm}13.6{\mu}m$ shell length, spontaneously have settled in the attachment substances. It have required 528 hours from fertilized eggs to early attached juvenile to become initial juvenile size of $245{\pm}15.8{\mu}m$ shell length.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.537-550
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• 2018

The development focus of a smart city has been changed gradually from a physical development aspect to a space development aspect. In a space development aspect, the major application technologies are Environment Technology (ET), Information Technology (IT) and Environment Information Technology. On the other hand, it is unclear if the space convergence in a smart city has been changed by the 3 technologies. Therefore, specific analysis was performed on the convergence change of smart city 4 spaces (District, Street, Building, Facility) using the 3 technologies. The convergence distribution ratio according to the periods (period 1 : 1972~1999, period 2 : 2000~2009, period 3 : 2010~2017) among the spaces, ET (Environment Technology), IT (Information Technology), ET+IT (Environment Information Technology) in a smart city were examined. The smart city was high in the order of 'District (53/43%) - Building (36/29.1%) - Street (22/17.9%) - Facility (12/10.0%)' in the number of applications and ratio of convergence (Technology Convergence) at Period 1 (1972~1999). The smart city was high in the order of 'District (223/32.4%) - Building (197/28.6%) - Street (195/28.3%) - Facility (74/14.8%)' in the number of applications and ratio of convergence (Technology Convergence) at Period 2 (2000~2009). At period 3, the District (467/33%) was also the highest. On the other hand, the street (384/27.4%) was higher than the building (361/25.8%) and facility (188/13.4%) in smart city space. Fourth, the smart city was high in the order of 'District - Building - Street - Facility' in the number of applications and ratio of convergence (Technology Convergence) at Periods 1 (1972~1999) and 2 (2000~2009). In contrast, the average of number was high in the order of 'Building - Street - District - Facility'. At period 3(2010~2017), the number of applications and the ratio of convergence was high 'District - Street - Building - Facility'; the average of number was the same as in period 1 and 2. As a result, smart city space has been changed by the development of macroscopic urban spaces in the initial stage. Since then, district space-centric development and building space are confused with devices/technologies and changed for citizen inflow. The building space has evolved continually and smart city space will be expected to revitalize the street space connecting completed buildings.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.12
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• pp.810-820
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• 2012

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) contents in marine sediment and edible fish (4 species) from the estuary near the Yongho wharf in Busan were determined to assess their presence and their potential health risk to the local population through fish consumption was also assessed. Levels of ${\Sigma}PCBs$ and ${\Sigma}DDTs$ in marine sediment were 3.22~197.65 and 1.77~20.27 ng/g dw, respectively. HCHs and endosulfan sulfate concentrations in bottom sediment were 1.42~6.08, 0.56~13.89 ng/g dw, respectively. The bottom sediment in the offshore of the Yongho wharf may be characterized as semi-polluted status with potential adverse marine biological effects in terms of sediment quality guidelines of US NOAA. The mean concentrations of ${\Sigma}PCBs$ in the tissues of olive flounder (Paralichthys olivaceus), Korean rockfish (Sebastes schlegelii), file fish (Stephanolepis cirrhifer) and abbysal searobin (Lepidotrigla abyssalis) were 67.37, 10.20, 48.26, 22.81 ng/g lw, respectively. DDTs and HCHs were also detected in all fish samples. Lifetime cancer risk and target hazard quotient to local residents due to those fish consumption were found to pose negligible cancer and non-cancer risk.

• Korean Journal of Optics and Photonics
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• v.13 no.3
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• pp.197-203
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• 2002

The TiO$_2$ coating solutions were synthesized with different concentrations (T1-0.7N, T2-2.0N) of hydrochloric acid used as catalyst. and TiO$_2$ thin films were prepared by sol-gel dip coating. Their structural and optical properties were examined as a function of calcination temperature. XRD results showed that T1 thin films calcined at 400~80$0^{\circ}C$ had the anatase phase, while those calcined at 100$0^{\circ}C$ had the rutile phase. T2 thin films calcined at 40$0^{\circ}C$ and $600^{\circ}C$ had the anatase phase, with the rutile phase for calcination at 80$0^{\circ}C$. Crystallinity of T2 thin films was superior to that of T1 thin films. The crystallite size of TiO$_2$ thin films increased with increasing calcination temperature, and the crystallite size of anatase phase in T2 thin films was larger than that in T1 thin films, but the crystallite size of rutile phase in T2 thin films was smaller. The surface morphology of the films showed that the films were formed more densely in the rutile phase than in the anatase phase, this phenomenon appeared conspicuously in T2 thin films. The transmittance of the samples with thin films on quartz glass calcined at 100$0^{\circ}C$ was significantly reduced at wavelength range about 300-700 nm due to the increased absorption originating from the change of crystallite phase and composition of the films and the scattering effect originating from increasing crystallite size. The refractive index of TiO$_2$ thin films increased, and hence the film thickness as well as the porosity of TiO$_2$ thin films decreased with increasing calcination temperature. Furthermore, the refractive index of T2 thin films was higher than T1 thin films, and porosity of T2 films was lower.

• The Korean Journal of Malacology
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• v.28 no.3
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• pp.197-213
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• 2012

This study was performed to know the community structure of macrobenthos and environmental factors at each 16 stations in the subtidal sandy bottoms of the southern coastal water of Jeju Island from July to November, 2011. Mean temperature and mean salinity were $20.2-22.7^{\circ}C$, 33.7-34.9 psu which shows stable water messes. Chlorophyll a concentrations of phytoplankton ranged from 0.71 to 1.71 mg/L (1.11 mg/L), showing higher July than September and November with a blooming in summer. The mean concentration values (the ranges in parentheses) of nitrate, phosphate, and silicate are 0.029-0.206 mg/L (0.101 mg/L), 0.001-0.027 mg/L (0.007 mg/L), 0.024-0.682 mg/L (0.454 mg/L), respectively. However, the values higher coastal zone due to influxes from the land. A total of 37 species was identified. of these mollusca comprised 29 secies (78.4%); Echinodermata 5 (13.5%); Arthropoda 3 (8.1%). density and biomass were estimated to be 550 ind./$m^2$ and 20,951.8 gwwt/$m^2$, respectively. Mollusca were the most dominant faunal group in terms of abundance (481 ind./$m^2$) and number of species as well, whereas bivalves were predominant in biomass (16,647.6 gwwt/$m^2$). The dominant species were Vasticardium burchardi, Oblimopa japonica, Mactar achatina, Bornatemishistrioiw akawai, Paphia vernicosa, Amusium japonicum, Glycymeris albolineata, Astriclypeus manni in 15-30 m. The seasonal variation appeared as distinct, Mollusca of individual and biomass. When summer was make a slow increase, after the highest decrease in autumn. The abundance of macrobenthic invertebrates showed significant correlation with environmental factors (Chlorophyll a, DIN, $SiO_2$, Fine sand, Very fine sand) in almost all sampling depths. The biodiversity, evenness richness index were appeared 1.56-2.50 (H'), 0.49-0.80 (E'), 4.12-4.67 (R) in each stations. The dominace index were appeared Highest in November and lowest in September.

• 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.

• Journal of Environmental Impact Assessment
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• v.24 no.4
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• pp.352-366
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• 2015

The purpose of this study is to offer the basic data to the habitat conservation and management by surveying and analysing the ecological characteristics such as the flora, vegetation structure and soil of Rhodotypos scandens habitat. The flora were summarized as 131 taxa including 57 families, 99 genera, 107 species, 1 subspecies, 17 varieties and 6 forms. The life forms grouped as in the follows; the megaphanerophytes(MM) were 21 taxa, 24 taxa of the microphanerophytes(M), 30 taxa of nanophanerophytes(N), 6 taxa of chamaiphytes(Ch), 20 taxa of hemicryptophytes(H), 17 taxa of geophytes(G), 12 taxa of therophytes(Th) and 1 taxa of hydrophytes(HH). The present conditions of communities were 8 types including Zelkova serrata, Quercus aliena, Ulmus parvifolia, Rhamnella frangulioides, Castanea crenata, Albizia julibrissin, Celtis sinensis and Robinia pseudoacacia. In case of the dominant species by layers, the tree layer species were Zelkova serrata, Quercus aliena, Ulmus parvifolia, Castanea crenata, Albizia julibrissin, Celtis sinensis and Robinia pseudoacacia, and the subtree layer species were Rhamnella frangulioides, Q. aliena, Z. serrata, A. julibrissin, U. parvifolia and Broussonetia kazinoki. The shrub layer species was Rhodotypos scandens. In the results of analyzing the diversity index, $H^{\prime}{_{max}}$ from 1.691 to 2.610, from 2.197 to 3.466 in H'max, from 0.646 to 0.903 in J' and from 0.097 to 0.354 in D. In the results of analysing the soil, there showed that acidity was 5.6, 0.5dS/m of electrical conductivity(EC), 59.1mg/kg of available $P_2O_5$, 49.7% of organic matter content, $0.4cmol^+/kg$ of exchangeable $K^+$, $13.5cmol^+/kg$ of exchangeable $Ca^{2+}$, $3.3cmol^+/kg$ of exchangeable $Mg^{2+}$.

• Journal of Mushroom
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• v.17 no.4
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• pp.197-204
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• 2019

In this study, smart farm technology was used by farmers cultivating 'CHIKUMASSHU T-011' in order to develop an optimal growth model for the precision cultivation of bottle-grown winter mushroom and the results of the same are mentioned herein. Farmers participating in the experiment used 60 ㎡ of bed area with 4 rows and 13 columns of shelf shape, 20 horsepower refrigerator, 100T of sandwich panel for insulation, 6 ultrasonic humidifiers, 12 kW of heating, and 20,000 bottles of Flammulina velutipes mushroom spores. The temperature, humidity, and carbon dioxide concentrations, which directly affect the growth of the mushroom, were collected and analyzed from the environmental sensors installed at the winter mushroom cultivation area. The initial temperature was found to be 14.5℃, which was maintained at 14℃ to 15℃ until the 10th day. In the restriction phase, the initial temperature was 4℃ and was maintained between 2℃ and 3℃ until the 15th day, while during the growth phase, it was maintained between 7.5℃ to 9.5℃. Analysis of the humidity data revealed initial humidity to be 100%, which varied between 88% to 98% during primordia formation period. The humidity remained between 77% to 96% until the 15th day, in the restriction phase and between 75% to 83% during the growth phase. The initial carbon dioxide concentration was 3,500 ppm and varied between 3,500 ppm to 6,000 ppm during primordia formation period and was maintained at 6,000 ppm until the 15th day. During the growth phase, the carbon dioxide concentration was found to be over 6,000 ppm. Fruiting body characteristics of 'CHIKUMASSHU T-011' cultivated in the farmhouse were as follows: Pileus diameter of 7.5 mm and thickness of 4.1 mm, stipe thickness of 3.3 mm, and length of 154.2 mm. The number of valid fruiting bodies was 1,048 unit per 1,400 mL bottle, and the individual weight was 0.71 g per unit. The yield of fruiting bodies was 402.8 g per 1,400 mL bottle.

• Journal of Korean Home Economics Education Association
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• v.18 no.3 s.41
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• pp.23-40
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• 2006

The purpose of this study was to examine co-ed high school students' concern for appearance, weight control attitude and food behavior. The subjects were 405 students(boys 197, girls 208) in Sokcho area. Most of the students had much interest in appearance, and their perception of body type was significant differences between boys and girls(p<,00l). 22.8% of boys expressed satisfaction at their own body type. while just 9,6% of the girls were contented with their body type. In interest toward weight control. 43.7% of the boys and 79.8% of the girls had a regard for weight control. In relationship between weight control interest and the body type perception, there were significant differences among group of caring about weight control. moderate group and indifferent group(p<,00l), regardless of gender. As a whole, 41.3% of group that cared about weight control found themselves a little fat. Most of the boys who considered themselves thin(24,4%) were much concerned about weight control. where as girls who thought of themselves as thin were little interested in. Body type satisfaction was significant differences among interested group, moderate group and indifferent group(p<.00l). It appeared that they had breakfast very irregularly, But 86.9% of the total students had dinner, which indicated dinner was taken relatively on a regular basis. Among three meals, dinner was skipped the least, 23,5% (17.8% of the boys and 28,9% of the girls) went without breakfast everyday. For the reason, 65.1% of the overall students didn't eat breakfast due to time constraints, and lunch(39.8%) and dinner(31.3%) were skipped largely because eating them was troublesome. Less students went without meals to lose weight. and lunch(7.0%) was skipped more than breakfast(1.3%), and dinner(13,8%) was skipped more than lunch, This study suggested that nutrition education for high school students should be planned to provide nutrition information regarding desirable weight control as well as modifying diets and food behaviors.