• Journal of Korean Society for Atmospheric Environment
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• v.24 no.2
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• pp.176-188
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• 2008

Anthropogenic emissions of nitrogen oxides and sulfur dioxide in Northeast Asia are of great concern because of their impact on air quality and atmospheric chemistry on regional and intercontinental scales. Satellite remote sensing based on DOAS (Differential Optical Absorption Spectroscopy) technique has been preferred to measure atmospheric trace species and to investigate their emission characteristics on regional and global scales. Absorption spectra obtained by the satellite-born instrument, SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography) have been utilized to retrieve the information of $SO_2$ and $NO_2$ over Northeast Asia. $SO_2$ levels over Northeast Asia were in order of East China, Yellow Sea, South Sea and Korean Peninsula with mean vertical columns of $1.78({\pm}1.0){\times}10^{16}$, $1.11({\pm}0.67){\times}10^{16}$, $0.60({\pm}0.63){\times}10^{16}$, $0.71({\pm}0.65){\times}10^{16}\;molecules/cm^2$, respectively. $NO_2$ levels were in order of East China, Yellow Sea, Korean Peninsula, and South Sea with mean vertical columns of $1.2({\pm}0.56){\times}10^{16}$, $0.38({\pm}0.19){\times}10^{16}$, $0.48({\pm}0.28){\times}10^{16}$, $0.26({\pm}0.16){\times}10^{16}\;molecules/cm^2$, respectively. High levels of $SO_2$ and $NO_2$ were observed over East China, in particular in winter by the contribution of heating fuel combustion exhausts. The $SO_2$ and $NO_2$ levels over East China were the highest in January with 34% and 42% higher over the annual means. Low levels of $SO_2$ ranged over Korean peninsula, while $NO_2$ levels were relatively high, in particular in winter. The $SO_2$ and $NO_2$ levels over Yellow Sea were relatively higher compared to those over Korean peninsula and South Sea, which could be mainly attributed to their transport from East China.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.7
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• pp.498-505
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• 2014

This study was carried out to characterize the ambient VOCs concentrations of industrial complex in Daegu city. VOCs concentrations of industrial complex area appeared to be higher than those in the non-industrial complex area as following order toluene > ethylbenzene > m,p-xylenes > o-xylene but benzene and chloroform were similar to each other sites. There was seasonal variation of VOCs concentrations in the industrial complex area, higher in summer and lower in winter. In particular the industrial complex area shows that higher on weekday than weekend and higher in the daytime than in the morning or nighttime because industrial complex area influenced by the chemicals. Correlation coefficients among VOCs were confirmed that VOCs of industrial complex area were more related to each other than those of non-industrial complex area and VOCs concentrations have shown generally negative correlation with wind speed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.154-164
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• 2016

This study analyzed the determinants of the turnover intention of emotion workers and recent social issues. In particular, this study examined whether the factors that determine the turnover intention affect the quality of service. The job characteristics of emotion workers were set up as an independent variable, and the job environment, organizational culture, such as emotional labor and how it affects the workers' behavior were investigated. How the independent variables influence the turnover of workers was investigated to mediate the emotional job satisfaction. The subjects were primarily targeted by the emotions of the workers engaged in large service accommodation, Kangwon. Among the environmental factors, the job characteristics and job duties are diverse factors and internal and external factors that can affect the compensation turnover intentions. Organizational culture as a factor was the human resources culture, open culture systems, and the hierarchical cultural factors affecting turnover intention. Among the emotional labor practices that also affects the surface of conduct, sincere acts influence the turnover intention. In addition, a one hypothesis testing job satisfaction was mediated by several factors with an impact, such as job diversity. Future empirical research should examined whether temporary full-time is an independent variable factor that can achieve a more fruitful conclusion.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.1
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• pp.26-37
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• 2009

Recently rapid environmental changes due to desertification and industrialization in China make a threat to Korea, especially during Asian Dust Event (ADE). This study was aimed to compare symptoms and behaviors related to ADE between Korea and China. We conducted questionnaires on self-reported symptoms and behaviors before and during ADE. Korean and Chinese subjects were grouped into children, adults, and elderly by nation (n=791). Statistical analyses were performed by $X^2$-test, Fisher's exact test, t-test and chow's test for comparing differences between Korean and Chinese. We estimated the odds ratio for perceived symptoms during ADE by preventive behavior, using Generalized Estimation Equation (GEE). The study indicated that there were significant differences between symptoms in Korea and those in China such as cold, cough, and sore throat, especially in elderly. Preventive behaviors such as avoiding outdoor activity and wearing sunglasses were more often performed in China than Korea. However wearing mask was more often performed in Korea than China. After adjusting for age, sex, educational level, and smoking status, the odds ratio (OR) of dry cough symptom in Korea was significantly decreased by closing the windows and wearing a mask during ADE. In China, the OR of dry cough symptom was decreased by wearing a mask and avoiding outdoor activity. We found that China which had higher performance of preventive behavior showed lower prevalence of symptoms during ADE than Korea. Also preventive behaviors could affects prevalence of symptoms during ADE. This results suggest that preventive behavior. could reduce symptoms during ADE and there are needed for. more attentions to reduce a threat of ADE.

• Cartoon and Animation Studies
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• s.31
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• pp.209-226
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• 2013

With rapidly changing multimedia environment, various artistic changes and digitalized up-to-date social infra, urban environment construction based on culture contents has been activated. The large image in front of urban building that is expressed as media-façade, increasing rapidly in a recent period, is not a new thing at all. In addition, IT technology molten in city space is testing the possibility of new media through the meeting with architecture. However, unlike its infra enlargement, the definition about media-façade is not clear so the system was constructed in a level of night lightscape or outdoor image advertisement. The purpose of this guideline is the regulation from the negative aspect rather than the possibility of various visual, artistic media expressions. Therefore, it could not show essential concept of media-façade. Moreover, most of companies or building owners focus on short-term profit and marketing effect rather than prepare various contents so they can not use constructed infra properly. After all, in many cases, they discolor the meaning of media-façade. This paper is a pilot study to grasp the current definition of media-façade to construct right guideline of media-façade. On the basis of this study, it will prepare academic definition of media-façade and construct the guideline for design evaluation.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.316-322
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• 2005

In this study, the concentration of 17 dioxin congeners in the soil samples near a waste incinerator with respect to distance from incinerator and wind directions were investigated. The effect of PCB source was investigated using the cluster analysis method. The total concentration and I-TEQ concentration of dioxin ranged from 31.065 to 7,257.499 pg/g(dry weight) and from 0.099 to 35.191 pg I-TEQ/g(dry weight.), respectively. There was a weak correlation(not statistically significant) observed between soil concentration and wind direction, and the distance from the incinerator. The reason may be due to the presence of the local combustion sources other than the target incinerator. The fraction of PCDFs and PCDDs was also examined to study the effect of incinerator. The fraction of PCDFs was decreased with the distance from the incinerator. The influence of target incinerator was found within a 500-meter radius. The high concentration in the for site was due to small incinerators and the use of agricultural chemicals such as PCP. To investigate the relationship between soil near the incinerator and the sources, the cluster analysis was conducted using the congener pattern. As a result soil samples were divided into four groups and were qualitatively estimated the influence of sources such as incinerator and PCP by comparing the congener pattern of each roups. It was thought that a cluster analysis was a useful statistical method for the source estimation of dioxin.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.12
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• pp.2205-2213
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• 2000

To investigate removal efficiency of dissolved matter by NF and RO, a pilot plant was operated for six months using groundwater treated by UF membrane. After the pilot plant operation, we performed autopsy test to identify characteristics of foulant attached on the membrane surface applying the used NF and RO in the pilot plant test. In autopsy test, we measured permeate flux and recovery rate of flux by chemical cleaning in each membrane. We also analyzed chemical cleaning disposal to examine component of foulant. Permeate flux of NF and RO1 showed rapid decline after 100 days of operation. Especially, reduction of specific flux in RO1 was more serious than in NF. Specific flux of RO2 with a low recovery rate resulted in gradual flux decline. Removal efficiencies of dissolved inorganic matters as a conductivity were 76.3%, 88.2% and 95.3% respectively for NF, RO1 and RO2, and RO2 presented the highest removal efficiency. And those of dissolved organic matters as TOC were about 80% for both NF and RO. The specific flux of membranes declined gradually from the feed water inlet to outlet of the membrane module and it showed that membrane fouling increased along the feed flow direction. Namely, concentration of pollutants became higher and volume of feed water was less as the feed flow approached to the outlet. It seemed that major foul ants were Ca consolidated into inorganic material and Si consolidated into organic material on the membrane surface. Fe was a great contribution to irreversible fouling. The SEM results indicated that the organic matter was attached to the first layer, closer to the membrane, and then inorganic matter with tetragonal shape layered over them. We could not observe biofouling because microorganism, which was cause of biofouling, was almost pretreated in UF membrane.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.5
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• pp.341-345
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• 2009

Continuous dry anaerobic digestion of organic solid wastes (30% TS, Total Solids) comprised of food waste and paper was performed under mesophilic condition. During the operation, hydraulic retention time (HRT) was decreased as follows: 150 d, 100 d, 60 d, and 40 d, which corresponded to the solid loading rate of 2.0, 3.0, 5.0, and 7.5 kg TS/$m^3$/d, respectively. Volumetric biogas production rate ($m^3$/$m^3$/d) increased as HRT decreased, and the highest biogas production rate of 3.49${\pm}$0.31 $m^3$/$m^3$/d was achieved at 40 d of HRT. At this HRT, high volatile solids (VS) reduction of 76% was maintained, and methane production yield of 0.25 $m^3$/kg $TS_{added}$ was achieved, indicating 67.4% conversion of organic solid waste to bioenergy. The highest biogas production yield of 0.52 $m^3$/kg $TS_{added}$ was achieved at 100 d of HRT, but it did not change much with respect to HRT. For the ease feed pumping, some amount of digester sludge was recycled and mixed with fresh feed to decrease the solid content. Recirculation volume of 5Q was found to be the optimal in this experimental condition. Specific methanogenic activity (SMA) of microorganisms at mesophilic-dry condition was 2.66, 1.94, and 1.20 mL $CH_4$/g VS/d using acetate, butyrate, and propionate as a substrate, respectively.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.649-655
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• 2010

This study investigated the degradation of phenol using sonication and/or UV-C. The effects of frequency, temperature, pH in solution, argon purging, with UV intensity were estimated in sonication-only, UV-only, and the combined reaction of sonication with UV. The optimum condition for degrading phenol in the sonication-only reaction was 35 kHz, $5^{\circ}C$, and pH 4. As this condition approximately 30% degradation of phenol was achieved within 360 min. However, phenol in the UV-only at $19.3\;mw/cm^2$ under the same condition was completely degraded within 60 min. In the combined system of sonication with UV, the degradation of phenol was well fitted to first-order rate model, and phenol was completely degraded within 360 min and 45 min at UV intensity of $7.6\;mW/cm^2$($17.3{\times}10^{-3}\;min^{-1}$) and $19.3\;mW/cm^2$($138.1{\times}10^{-3}\;min^{-1}$), respectively. Adding methanol, as a radical scavenger, in the phenol degradation in the sonication reaction indicates that OH radical is a major factor in the degradation of phenol. The order of degradation efficiencies of phenol was in the order of as follows; combined reaction of sonication with UV > UV-only > sonication-only.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.2
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• pp.98-108
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• 2006

The vessels, already built and is operating in Korea, have the hull form of catamaran, with LOA(Length Over All) 15 m, LBP(Length Between Perpendiculars) 12 m, GT(Gross Tonnage) 9.77ton, Light Load Displacement 15.1ton. Korean Society of Ship Inspection & Technology, Chungnam National University, Inha University, Seoul National University and Advance Marine Tech co. ltd developed by cooperation it for fishing vessels. And it used FRP(Fiber Reinforced Plastics) for hull material and main engine of diesel $360ps{\times}2800rpm{\times}2sets$ with a water jet system. Based on these results, this paper describe small leisure fishing vessels with multi-hull, in relation to the project of CTYS(Regional Reserch Center for Transportation System of Yellow Sea Inha University) that aimed to development of trimaran hull form(LOA=17m, LBP=14m(Side Hull=6m), GT=9.77ton, Light Weight=11.2 ton).