• 한국환경보건학회지
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• 제48권4호
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• pp.236-243
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• 2022

Background: In the case of multiple exposures to different types of heavy metals, such as the conditions faced by residents living near a smelter, it would be preferable to group hazardous substances with similar characteristics rather than individually related substances and evaluate the effects of each group on the human body. Objectives: The purpose of this study is to evaluate the utility of factor analysis in the assessment of health effects caused by exposure to two or more hazardous substances with similar characteristics, such as in the case of residents living near a smelter. Methods: Heavy metal concentration data for 572 people living in the vicinity of the Janghang smelter area were grouped based on several subfactors according to their characteristics using factor analysis. Using these factor scores as an independent variable, multiple regression analysis was performed on health effect markers. Results: Through factor analysis, three subfactors were extracted. Factor 1 contained copper and zinc in serum and revealed a common characteristic of the enzyme co-factor in the human body. Factor 2 involved urinary cadmium and arsenic, which are harmful metals related to kidney damage. Factor 3 encompassed blood mercury and lead, which are classified as related to cardiovascular disease. As a result of multiple linear regression analysis, it was found that using the factor index derived through factor analysis as an independent variable is more advantageous in assessing the relevance to health effects than when analyzing the two heavy metals by including them in a single regression model. Conclusions: The results of this study suggest that regression analysis linked with factor analysis is a good alternative in that it can simultaneously identify the effects of heavy metals with similar properties while overcoming multicollinearity that may occur in environmental epidemiologic studies on exposure to various types of heavy metals.

• 환경위생공학
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• 제22권1호
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• pp.67-74
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• 2007

The purpose of this study is to provide the necessarily basic data of the ideal growth of the students by investigating the effect of the student's stress due to the parent's achievement pressure. The sample of this study are In students consisting of 51 boys and 49 girls in the 3rd grade classes of "J" middle school located in Siheung city, Kyungki-do. The observed materials are used to investigate the parent's achievement pressure and the level of stress. Based on the observed data, the frequency, correlation, and t-test have been gained. The results are summarized as follows : 1. The perception of the parent's achievement pressure is shown more by the boy's achievement pressure($44.2{\pm}9.9$) than the girl's achievement pressure($39.939{\pm}11.089$), among the high level students. 2. The perception of the parent's achievement pressure is shown more the high($43.0{\pm}10.7$) and middle($42.9{\pm}11.8$) level students than the low($39.7{\pm}8.00$) level students. 3. The stress of male students was high in the Solving Problem stress factor with by the mean of $15.1{\pm}3.7$, and the stress of female students was high in the Self-Control stress factor with the mean of $13.3{\pm}3.9$. 4. The stress of high, middle, low level student was high in the Solution of Matter stress factor with the mean of $14.2{\pm}3.9$. 5. The results were the main cause of the stress than the parent's achievement pressure.

• Environmental Analysis Health and Toxicology
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• 제21권3호
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• pp.229-238
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• 2006

Although, mercury (Hg) is not a naturally abundant element in the environment, residues frequently occur in many environmental compartments because of widespread contamination from industrial and agricultural practices. This research evaluated Hg-B concentrations of general population who was not occupationally exposed. And also evaluates the association between life factor and health effect with Hg-B concentration of general adult through interrelationship estimation and index about kidney function and oxidative damage that appeared by questionnaire survey and medical examination. Average concentration of Hg-B was 3.19 $\mu$g/L (ND$\sim$8.64 $\mu$g/L), and persons who exceed mercury exposure level (5 $\mu$g/L) presented in WHO (1990) appeared by 16 (7.0%). High-risk group (smoking and meat main intake group) had significantly higher Hg-B concentration than low-risk group (non-smoking and vegetable diet main intake group) (p < 0.05, low-risk group: 3.30 $\mu$g/L (ND$\sim$8.64 $\mu$g/L), high-risk group: 4.27 $\mu$g/L (ND$\sim$7.84 $\mu$g/L).

• Journal of Microbiology and Biotechnology
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• 제16권12호
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• pp.1940-1946
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• 2006

The influence of environmental conditions on the ganoderic acid (GA) content in the fungus Ganoderma lucidum was investigated using a one-factor-at-a-time design and orthogonal design. Among the various medium components examined, sucrose, soybean powder or peptone, ferrous sulfate, and pH 6.0 were the most suitable carbon source (factor A), nitrogen source (factor B), mineral source (factor C), and initial pH (factor D), respectively, for the GA content in the one-factor-at-a-time design. According to the orthogonal design, the order of effect for the four factors on the GA content was A>C>D>B. The best level of factor A was $A_2$ (sucrose) with a value of +0.34 mg/100 mg DW. The optimal treatment combination was $A_2B_1C_3D_1$ with which the GA content reached up to 2.63$\pm$0.011 mg/100 mg DW. The interactions between the mineral ion and the nitrogen source, and the mineral ion and the pH were both highly significant (P<0.01). The highest interaction effect was ($B_2{\times}D_2$) with a value of +0.19 mg/100 mg DW, which was higher than the level effect value for $B_2$ (peptone) and D$_2$ (pH 5.0). Therefore, the results proved that interactions between factors cannot be ignored. The results also indicated the importance of the interactions between the factors, which may help to understand the metabolic pathway leading to triterpene biosynthesis and the expression and regulation of the key enzymes involved.

• 한국식생활문화학회지
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• 제27권3호
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• pp.251-260
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• 2012

This study was designed to provide practical environmental marketing data by measuring the effect of environmental marketing on customer loyalty and trust at coffee stores. The results were obtained by empirical analysis and are summarized as follows. The first hypothesis, the effect of environmental marketing on consumer trust at coffee stores, showed that environmental marketing at coffee stores had a statistically significant positive effect on consumer trust. Price, product, and facilities as sub-factors of environmental marketing at coffee stores had effects on consumer trust. Especially, facilities was the highest. The second hypothesis, the effect of environmental marketing on customer loyalty at coffee stores, showed that environmental marketing at coffee stores had a statistically significant positive effect on customer loyalty. Price, product, and facilities as sub-factors of environmental marketing at coffee stores had effects on customer loyalty. Especially, facilities was the highest. The third hypothesis, the effect of consumer trust on customer loyalty at coffee stores, showed that consumer trust at coffee stores had a statistically significant positive effect on customer loyalty. Improvement of consumer trust by environmental marketing was an important factor in improving customer loyalty. As for these findings, price, product, and facilities as sub-factors of environmental marketing at coffee stores had effects on consumer trust and loyalty. Consequently, these findings provide helpful information for coffee stores to plan environmental marketing strategies and establish direction, and they can be used for management activities.

• Asia pacific journal of information systems
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• 제26권1호
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• pp.189-210
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• 2016

The current study attempts to expand our understanding of the determinants of energy-saving technology (EST) use by focusing on the individual aspects of environmental behaviors. This study integrates the hedonic, normative, and gain goals to explain the causal relationship between users and EST use. By adopting Goal-Framing Theory, this study proposed three individual goal frames in the environmental context: hedonic (perceived pleasurability), normative (social norms), and gain goals (legislative pressure and economic factor). Partial Least Square (PLS) was used to analyze the data from 104 respondents. Eight of the ten hypotheses were strongly supported. We found that social norms, perceived pleasurability, economic factor, and legislative pressure had positive and significant effects on attitude to EST use. Interestingly, we found that media influence did not have a severe effect on perceived pleasurability, and that the economic factor enforces mainly positive attitude to EST. Important theoretical and practical implications of these findings are discussed.

• 한국산업융합학회 논문집
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• 제25권1호
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• pp.101-110
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• 2022

For this purpose, the authors proposed and proved usefulness of the modified mean skin temperature which is integrated mean radiation temperature and the effect of floor contacted heat conduction. The mean radiation temperature is applied form factor between half cross-legged human body and surrounding wall of indoor. In addition the floor contacted heat conduction is applied heat transfer coefficient of half cross-legged human body. Eight Korean young men were targeted for the experiment. From the experiment the authors excerpted physiological reaction and psychological reaction in Ondol environment which is combined physiccal environmental factor of artificial climate chamber, air and floor temperature. As a result of the experiment it is confirmed that heat conduction has more impact than heat exchange from existing research for the heat exchange between half cross-legged human body and surrounding wall in Ondol thermal environment. Thereby, it is proved the effectiveness of the modified mean skin temperature which is added floor contacted temperature to the Ondol thermal environmental evaluation index.

• 한국환경과학회지
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• 제14권9호
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• pp.851-860
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• 2005

In order to how well predict ISCST3(lndustrial Source Complex Short Term version 3) model dispersion of air pollutant at point source, sensitivity was analysed necessary parameters change. ISCST3 model is Gaussian plume model. Model calculation was performed with change of the wind speed, atmospheric stability and mixing height while the wind direction and ambient temperature are fixed. Fixed factors are wind direction as the south wind(l80") and temperature as 298 K(25 "C). Model's sensitivity is analyzed as wind speed, atmospheric stability and mixing height change. Data of stack are input by inner diameter of 2m, stack height of 30m, emission temperature of 40 "C, outlet velocity of 10m/s. On the whole, main factor which affects in atmospheric dispersion is wind speed and atmospheric stability at ISCST3 model. However it is effect of atmospheric stability rather than effect of distance downwind. Factor that exert big influence in determining point of maximum concentration is wind speed. Meanwhile, influence of mixing height is a little or almost not.

• 한국환경과학회지
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• 제26권9호
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• pp.1057-1072
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• 2017

In order to investigate the effect of air temperature reduction on an urban neighborhood park, air temperature data from five inside locations (forest, pine tree, lawn, brick and pergola) depending on surface types and three outside locations (Suwon, Maetan and Kwonsun) depending on urban forms were collected during the summer 2016 and compared. The forest location had the lowest mean air temperature amongst all locations sampled, though the mean difference between this and the other four locations in the park was relatively small ($0.2-0.5^{\circ}C$). In the daytime, the greatest mean difference between the forest location and the two locations exposed to direct beam solar radiation (brick and lawn) was $0.5-0.8^{\circ}C$ (Max. $1.6-2.1^{\circ}C$). In the nighttime, the mean difference between the forest location and the other four locations in the park was small, though differences between the forest location and locations with grass cover (pine tree and lawn) reached a maximum of $0.9-1.7^{\circ}C$. Comparing air temperature between sunny and shaded locations, the shaded locations showed a maximum of $1.5^{\circ}C$ lower temperature in the daytime and $0.7^{\circ}C$ higher in the nighttime. Comparing the air temperature of the forest location with those of the residential (Kwonsun) and apartment (Maetan) locations, the mean air temperature difference was $0.8-1.0^{\circ}C$, higher than those measured between the forest location and the other park locations. The temperatures measured in the forest location were mean $0.9-1.3^{\circ}C$ (Max. $2.0-3.9^{\circ}C$) lower in the daytime than for the residential and apartment locations and mean $0.4-1.0^{\circ}C$ (Max. $1.3-3.1^{\circ}C$) lower in the nighttime. During the hottest period of each month, the difference was greater than the mean monthly differences, with temperatures in the residential and apartment locations mean $1.0-1.6^{\circ}C$ higher than those measured in the forest location. The effect of air temperature reduction on sampling locations within the park and a relatively high thermal environment on the urban sampling locations was clearly evident in the daytime, and the shading effect of trees in the forest location must be most effective. In the nighttime, areas with a high sky view factor and surface types with high evapotranspiration potential (e.g. grass) showed the maximum air temperature reduction. In the urban areas outside the park, the low-rise building area, with a high sky view factor, showed high air temperature due to the effect of solar (shortwave) radiation during the daytime, while in the nighttime the area with high-rise buildings, and hence a low sky view factor, showed high air temperature due to the effect of terrestrial (longwave) radiation emitted by surrounding high-rise building surfaces. The effect of air temperature reduction on the park with a high thermal environment in the city was clearly evident in the daytime, and the shading effect of trees in the forest location must be most effective. In the nighttime, areas with high sky view factor and surface types (e.g., grass) with evapotranspiration effect showed maximum air temperature reduction. In the urban areas outside the park, the high sky view factor area (low-rise building area) showed high air temperature due to the effect of solar (shortwave) radiation during the daytime, but in the nighttime the low sky view factor area (high-rise building area) showed high air temperature due to the effect of terrestrial (longwave) radiation emitted surrounding high-rise building surfaces.

• 환경영향평가
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• 제16권4호
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• pp.277-283
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• 2007

Since the Kyoto Protocol became into effect, Korea has been expected to be part of the Annex I countries performing the duty of GHG reduction in the phase of post-Kyoto. Therefore, it is necessary to develop emission factors appropriate to Korean circumstances. In order to develop emission factors this study utilized the CleanSYS, which is the real-time monitoring system for industrial smoke stacks to calculate the emission rate of $CO_2$ continuously. In this study, the main focus was on the power generation plants emitting the largest amount of $CO_2$ among the sectors of fossil fuel combustion. Also, an examination on the comparison of $CO_2$ emission was made among 3 generation plants using the different types of fuels such as bituminous coal and LNG; one for coal and others for LNG. The $CO_2$ concentration of the coal fired plant showed Ave. 13.85 %(10,384 ton/day). The LNG fired plants showed 3.16 %(1,031 ton/day) and 3.19 %(1,209 ton/day), respectably. Consequently, by calculating the emission factors using the above results, it was found that the bituminous coal fired power plant had the $CO_2$ emission factor average of 88,726 kg/TJ, and the LNG fired power plants had the $CO_2$ average emission factors of 56,971 kg/TJ and 55,012 kg/TJ respectably which were similar to the IPCC emission factor.