• Analytical Science and Technology
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• v.29 no.3
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• pp.114-125
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• 2016

In this study, 165 wastewater discharge facilities in 10 business types were investigated with regard to 24 specific hazardous substances that included heavy metals, VOCs, CN, and phenol in the Gwangju city. Cu in the range from from 0.008 to 35.420 mg/L was detected in all business types and the detection rate was 46.8 %. Other heavy metals, such as Cd, As, Hg, Pb, and Cr⁺⁶ were detected as well. However, their detection rates ranged between 0.6 and 1.8 %. CN and phenol were detected in one and five facilities, respectively. 12 species of VOCs were detected: chloroform 80.6 % (0.42 to 81.60 μg/L), benzene 16.4 % (1.49 to 3.31 μg/L), trichloroethylene 11.5 % (1.78 to 6.02 μg/L), 1,1-dichloroethylene 10.3 % (1.23 to 5.89 μg/L), and dichloromethane 8.5 % (0.28 to 968.86 μg/L) in the detection rate order. The concentration of VOCs was detected in trace amounts, except for dichloromethane that exceeded the effluent quality standard in three business types, namely, metal manufacturing, food industry, and car washing facility. Chloroform was detected in all business types, where 24.88 μg/L were detected in the laundry business and 53.41 μg/L in the water supply business; the mean concentration of chloroform in these two business types was higher than elsewhere. Therefore, for the disposal of non-degradable specific hazardous substances in industrial wastewater, it is necessary to introduce physical and chemical processes, such as activated carbon adsorption, fenton oxidation, ozone treatment, as well as photocatalyst and the UV radiation.

• Journal of Astronomy and Space Sciences
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• v.22 no.3
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• pp.329-352
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• 2005

Long term observations of full-disk Lyman-o irradiance have been made by the instruments on various satellites. In addition, several sounding rockets dating back to the 1950s and up through the present have measured the $Lyman-{\alpha}$ irradiance. Previous full disk $Lyman-{\alpha}$ images of the sun have been very interesting and useful scientifically, but have been only five-minute 'snapshots' obtained on sounding rocket flights. All of these observations to date have been snapshots, with no time resolution to observe changes in the chromospheric structure as a result of the evolving magnetic field, and its effect on the Lyman-o intensity. The $Lyman-{\alpha}$ Imaging Solar Telescope(LIST) can provide a unique opportunity for the study of the sun in the $Lyman-{\alpha}$ region with the high time and spatial resolution for the first time. Up to the 2nd year development, the preliminary design of the optics, mechanical structure and electronics system has been completed. Also the mechanical structure analysis, thermal analysis were performed and the material for the structure was chosen as a result of these analyses. And the test plan and the verification matrix were decided. The operation systems, technical and scientific operation, were studied and finally decided. Those are the technical operation, mechanical working modes for the observation and safety, the scientific operation and the process of the acquired data. The basic techniques acquired through the development of satellite based solar telescope are essential for the construction of space environment forecast system in the future. The techniques which we developed through this study, like mechanical, optical and data processing techniques, could be applied extensively not only to the process of the future production of flight models of this kind, but also to the related industries. Also, we can utilize the scientific achievements which are obtained throughout the project And these can be utilized to build a high resolution photometric detectors for military and commercial purposes. It is also believed that we will be able to apply several acquired techniques for the development of the Korean satellite projects in the future.

• Cartoon and Animation Studies
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• s.30
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• pp.263-291
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• 2013

In this article, I analyze Korean Dong-in culture and its relationship with Yaoi, focusing on the changes in the 1990s. While Korean Dong-in culture has developed under the influence of Japanese Dojin culture, it is not well-known that Korean Dong-in culture has its own characteristics, reflecting the unique situations surrounding the Korean society. The reason that I pay attention to the changes in the 1990s is that they have created the foundation of the current Korean dong-in culture through changes such as the import and reception of Yaoi, the creation of 'virtual community' in PC telecommunication, the enforcement of Juvenile Protection Law, and the inauguration of 'Comic World,' Among them, the import and reception of Yaoi, a genre characterized by homosexuality including sexual relationship and fanwork, played a decisive role in the change of dong-in culture from manwha circle by highly motivated amatuer artists to fandom. The circumstances that original manhwa dong-in by manwha circle and Yaoi by manhwa fandom coexisted by the mid-1990s, the enforcement of Juvenile Protection Law and the lift of ban on Japanese popular culture rapidly weakened original manhwa dong-in. Also, the popularity of Comic World as a new type of dong-in events reflected the spread of fanwork as a new trend of Korean dong-in. In summary, the import and reception of Yaoi should be considered as one of the important changes in the 1990s Korean Dong-in culture, because 1) Korean women considered Yaoi as a liberating subculture by its powerful contents-homosexuality with sexual relationship, and 2) Yaoi succeeded in attracting new population favoring fanwork as a major trend in Korean Dong-in, differentiated from original manhwa circle population.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.6
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• pp.631-638
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• 2010

The objective of this study was to evaluate the efficiency of zerovalent iron and basic oxygen furnace slag on arsenic stabilization in soils. For this, arsenic (V) contaminated soil and roxarsone contaminated soil were incubated after incorporation with zerovalent iron (ZVI) or basic oxygen furnace slage (BOFS) at four different levels (0%, 1%, 3%, and 5%) for 30 days and then the residual concentrations of arsenic were analysed following extraction with aqua reqia, 1N HCl and 0.01 M $CaCl_2$. The total concentration of arsenic was 2,285 mg/kg in the As(V) contaminated soil and 6.5 mg/kg in the roxarsone contaminated soil. 1 N HCl extractable arsenic concentration in the As(V) contaminated soil was initially 1,351 mg/kg and this was significantly declined by 713~1,034 mg/kg following incubation with ZVI while BOFS treatment showed no effect on the stabilization of inorganic arsenate except 5% treatment which showed around 100 mg/kg reduction in 1N HCl extractable arsenic. Similarly, in the roxarsone contaminated soil 1N HCl extractable concentration of arsenic was reduced from 3.13 mg/kg to 0.69 mg/kg with ZVI treatment increased from 1% to 5% while BOFS treatment did not lead to any statistically significant reduction. Available (0.01M $CaCl_2$ extractable) arsenic was initially 0.85 mg/kg in the As(V) contaminated soil and this declined by 0.79 mg/kg following incorporation with 5% ZVI, which accounted for more than 90% of the available As in the control. When As(V)-contaminated soil was treated with BOFS, the available arsenic was increased due to competing effect of the phosphate originated from BOFS with arsenate for the adsorption sites. For the roxarsone contaminated soil, the greater the treatment of ZVI or BOFS, the lower the available arsenic concentration although it was still higher than that of the control.

• Journal of Nutrition and Health
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• v.53 no.5
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• pp.488-502
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• 2020

Purpose: This study examined the factors influencing Nutrition Quotient for adults (NQ-A), focusing on workers in the manufacturing industry. Methods: The participants were 738 industrial workers in Gwangju. Their dietary information was analyzed using a questionnaire of NQ-A, which consisted of 21 checklist items and the general characteristics of the subjects. The scores of NQ-A and its 4 factors (balance, moderation, diversity, and dietary behavior) were calculated according to the general characteristics of subjects. The data were analyzed using a χ² test, t-test, correlation, and multiple regression using SPSS 21.0 program. Results: The mean NQ-A score was 45.3 for the total subjects, indicating a low grade. Non-shift workers showed significantly higher scores for balance, diversity, and moderation factors than shift workers. Forty-three (8.7%) shift workers and 123 (50.8%) non-shift workers had good NQ-A scores, whereas 453 (91.3%) shift workers and 119 (49.2%) non-shift workers required monitoring for nutrition. The significant influencing factors of NQ-A were the working pattern (p < 0.001), gender (p < 0.001), family composition (p < 0.001), age (p < 0.001), and household income (p < 0.001). As a result of multiple regression analysis, there was a significant difference in the NQ-A score for moderation (F = 141.930, p < 0.001), diversity (F = 98.998, p < 0.001), balance (F = 52.329, p < 0.001), and dietary behavior (F = 12.895, p < 0.001). As a result, shift work and gender had the greatest influence on the balance (β = -0.372, p < 0.001), diversity (β = -0.316, p < 0.001), and moderation (β = -0.507, p < 0.001) factors in NQ-A. Gender had the most influence on the dietary behavior in NQ-A. Conclusion: Shift work and gender were significant factors affecting NQ-A. To manage workers' health better, it will be necessary to prepare a nutrition education program according to the type of working pattern and gender.

• Journal of Distribution Research
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• v.17 no.5
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• pp.39-57
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• 2012

The unabated influx of micro businesses has turned the Korean retailing market to a rat race, which causes severe financial distress for micro business owners due to heavy competition. The woes of these micro business owner's are exacerbated by the presence of large scale distributors such as Super Supermarket(SSM) and large discount stores. In summary, the Korean retail market is overburdened an uneconomically viable. Retailing has low barriers to entry which attracts unskilled labor or those with little capital. These start-ups have low opportunity costs since they would make low wages elsewhere in the economy. Thus, these owners are content with relatively low returns on their investment. These 'subsistence ventures' are maintained for economical viability rather than economic growth. These 'subsistence ventures' intensifies competition among small-scale businesses. The presence of large retail corporations also aggravates the situation. The recent stagnation of the economy has worsened the retail market in Korea. The overwhelming competition solidifies the coarse structural system and the prolonged economic sluggishness has increased the risk of insolvency for micro business owners. As the economy continues to stagnate, the imminent risk in retailing market will rise up to surface threatening economic stability. More systematic inflows and outflows of retailers are required in order to redress this structural problem. It has been empirically shown that the self-employment rate is high in Korea compared to other OECD countries. To draw the comparison of self-employment rate by industry, Korea shows high rates among transportation, whole sale, retail, education, lodging, and restaurants. In the case of the transportation and education service sectors, this high rate can be explained by the idiosyncratic nature of Korean culture. In the transportation sector, political policies favor private cap service and private freight carriers. In the education service sector, Koreans put particular emphasis on education that leads to many private institutions that outnumber other OECD countries. For these singular reasons, Korea maintains high micro business, self-employed rates particularly in retailing. A comparable nation is Japan, with its similar social, economic, cultural environment among OECD countries. Unlike Korea, Japan has much lower rates of micro business which continues to decrease. Also Korean retailers are much more destitute than Japanese. The fundamental problem of Korean retailing is the involuntary exit of these 'subsistence ventures,' micro businesses with low margins, in which a small drop in demand can lead to financial difficulties for the owner. This problem will be exacerbated when Korean babyboomers retire and join the micro business ventures. The first priority in order to cope with the severity of oversupply in retailing is to provide better opportunities for the potential self-employers. There should be viable alternatives to subsistent ventures. Strengthening the retirement program, scrutiny of exit process, reconfiguration of policy funds are the recommendations.

• Journal of Distribution Science
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• v.9 no.2
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• pp.83-95
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• 2011

Conventional markets in Korea have played a pivotal role in the vitalization of local communities and economies along with the distribution of products. Although many people believe the markets to be disorderly, they are lively and provide local people with things to enjoy, watch and buy. However, superstores have undergone a mushrooming proliferation since Korea opened its gates to multinational superstores in 1996. This phenomenon has caused a crisis for Korea's conventional markets. They have lost their competitiveness because of this environmental change, inefficient management, and their outmoded facilities. Government efforts to revitalize the markets have centered on redevelopment of the facilities, a perspective that has caused not only the fall of the old business districts but also the decline of the distribution function. Under these conditions, the traditional market has re-entered into competition. The Korean government enacted a special law to revitalize the conventional markets and has been implementing many policies to support them since 2003. In 2009, the government amended the law and adopted the Business Improvement District System. The government also changed the official term from 'old markets' to 'Conventional markets'. Despite this legal amendment, though, we still need to re-establish the concept of the Conventional market. Historically, markets grew up spontaneously to dispose of surplus products. Some manmade markets were established through urban planning or as public facilities. Their businesses transactions have always been based on mutual trust between consumers and trades people, the traditional way of commercial dealing. Conventional markets can be defined, then, as creatures of societal necessity where transactions for services and products are based on mutual trust. Problematically, unlisted markets are left out of government support. Although unlisted markets have performed almost the same functions as listed markets, they exist only as a statistic as far as the special law is concerned. In some areas, there are more unlisted markets than unlisted ones. Therefore, it is necessary to establish systematic management methods for the unlisted markets. Some unlisted markets received support in the form of facility improvement from local governments' budgets in the early stage of the special law's enforcement. The current government also assists with safety issues involving unlisted markets; however, the current special law provides no legal framework for unlisted markets. Moreover, consumers cannot tell the difference between unlisted markets and listed ones. Finding a solution to this problemrequires new standards and a wider scope of support by which the efficiency of the market improvement support system might be enhanced.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.109-118
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• 1985

This experiment was carried out to evaluate the water quality in the lower part of the Nagdong river in Korea. Three hundred and sixty water samples were collected from the 15 stations from December 1981 to November 1982 by tide(see Fig.1). Water temperature, pH, chloride ion, salinity, total coliform, fecal coliform, viable cell count and the composition of coliform were observed to evaluate the water quality. The variations of water temperature was ranged from $2.0^{\circ}C\;to\;29.5^{\circ}C$ and as mean value from $15.8^{\circ}C\;to\;18.9^{\circ}C$. The range of pH was 6.00-8.88 and 7.20-7.96 as mean value. The concentration of chloride ion from St. 1 to 5 was higher as 17.51-771 mg/l in flood tide than 13.12-264.58 mg/l in ebb tide. Specially, water quality at St.1 (Samrangjin) which located about 46 km far from Hadan was also influenced by tide. Salinities of water in flood tide were a litte higher ($11.05{\sim}31.08\%0$) than those of in ebb tide ($7.80{\sim}29.28\%0$). Total coliform MPN's ranged from 3.6/100 m/l to 460,000/100ml. The geometric mean value of the upper area (included St. $1{\sim}3$) was $259{\sim}538/100ml$, that of the middle area (included St. $4{\sim}6$) was $1,097{\sim}39,544/100ml$ for it leveled heavy contamination. Specially, in the ebb tide St. 10 was influenced by St. 6 and 7. In the upper area, the geometric mean value of fecal coliform MPN's was $109{\sim}199/100ml$ but in the area in cluded St. 5, 6 and 7 were heavily contaminated by domestic sewage, waste water from the factories area and bird's excrement. Composition of coliform was $17\%$ Escherichia coli group, $33\%$ Citrobacter freundii group, $28\%$ Enterobacter aerogenes group and $21\%$ others. Plate count of samples was varied from <30 to $3.9{\times}10^4/ml$ during the study period.

• Journal of Intelligence and Information Systems
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• v.17 no.4
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• pp.213-226
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• 2011

In global supply chain, the scheduling problems of large products such as ships, airplanes, space shuttles, assembled constructions, and/or automobiles are complicated by nature. New scheduling systems are often developed in order to reduce inherent computational complexity. As a result, a problem can be decomposed into small sub-problems, problems that contain independently small scheduling systems integrating into the initial problem. As one of the authors experienced, DAS (Daewoo Shipbuilding Scheduling System) has adopted a two-layered hierarchical architecture. In the hierarchical architecture, individual scheduling systems composed of a high-level dock scheduler, DAS-ERECT and low-level assembly plant schedulers, DAS-PBS, DAS-3DS, DAS-NPS, and DAS-A7 try to search the best schedules under their own constraints. Moreover, the steep growth of communication technology and logistics enables it to introduce distributed multi-nation production plants by which different parts are produced by designated plants. Therefore vertical and lateral coordination among decomposed scheduling systems is necessary. No standard coordination mechanism of multiple scheduling systems exists, even though there are various scheduling systems existing in the area of scheduling research. Previous research regarding the coordination mechanism has mainly focused on external conversation without capacity model. Prior research has heavily focuses on agent-based coordination in the area of agent research. Yet, no scheduling domain has been developed. Previous research regarding the agent-based scheduling has paid its ample attention to internal coordination of scheduling process, a process that has not been efficient. In this study, we suggest a general framework for agent-based coordination of multiple scheduling systems in global supply chain. The purpose of this study was to design a standard coordination mechanism. To do so, we first define an individual scheduling agent responsible for their own plants and a meta-level coordination agent involved with each individual scheduling agent. We then suggest variables and values describing the individual scheduling agent and meta-level coordination agent. These variables and values are represented by Backus-Naur Form. Second, we suggest scheduling agent communication protocols for each scheduling agent topology classified into the system architectures, existence or nonexistence of coordinator, and directions of coordination. If there was a coordinating agent, an individual scheduling agent could communicate with another individual agent indirectly through the coordinator. On the other hand, if there was not any coordinating agent existing, an individual scheduling agent should communicate with another individual agent directly. To apply agent communication language specifically to the scheduling coordination domain, we had to additionally define an inner language, a language that suitably expresses scheduling coordination. A scheduling agent communication language is devised for the communication among agents independent of domain. We adopt three message layers which are ACL layer, scheduling coordination layer, and industry-specific layer. The ACL layer is a domain independent outer language layer. The scheduling coordination layer has terms necessary for scheduling coordination. The industry-specific layer expresses the industry specification. Third, in order to improve the efficiency of communication among scheduling agents and avoid possible infinite loops, we suggest a look-ahead load balancing model which supports to monitor participating agents and to analyze the status of the agents. To build the look-ahead load balancing model, the status of participating agents should be monitored. Most of all, the amount of sharing information should be considered. If complete information is collected, updating and maintenance cost of sharing information will be increasing although the frequency of communication will be decreasing. Therefore the level of detail and updating period of sharing information should be decided contingently. By means of this standard coordination mechanism, we can easily model coordination processes of multiple scheduling systems into supply chain. Finally, we apply this mechanism to shipbuilding domain and develop a prototype system which consists of a dock-scheduling agent, four assembly- plant-scheduling agents, and a meta-level coordination agent. A series of experiments using the real world data are used to empirically examine this mechanism. The results of this study show that the effect of agent-based platform on coordinated scheduling is evident in terms of the number of tardy jobs, tardiness, and makespan.

• Weed & Turfgrass Science
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• v.7 no.1
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• pp.35-45
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• 2018

The seaweed Ulva spp., which is frequently bloomed in coastal areas, have negatively affected on marine ecosystem and industrial activities. Therefore, many researches have been conducted to solve this problem in the worldwide. In this study, we carried out several experiments to develop the methods for effectively controlling Ulva growth through an alone or mixture application of chemical and temperature. Three chemical mixtures ($H_2O_2$+N-vanillylnonanamide; $H_2O_2$+nonanoic acid; $H_2O_2$+sodium citrate), those had a synergistic effect to the death of Ulva australis (ULAUS), were found out. On the other hand, the death of ULAUS was significantly enhanced and accelerated as some chemicals were briefly treated with warm water of $40^{\circ}C$ rather than $25^{\circ}C$, showing that peracetic acid 100 ppm, sodium percarbonate 100 ppm, and hydrogen peroxide 30 ppm has a better activity than that of sodium chlorite 200 ppm and menadione sodium bisulfite 4 ppm. In addition, a strong synergistic effect to the death of ULAUS thallus was also observed when the sodium citrate 1,000 ppm (pH 3.0) or acetic acid 200 ppm (pH 3.5) solution prepared in f/2 medium were treated in a short time at $40^{\circ}C$. However, an additive effect was only appeared as pH values of their solutions were increased to 8.0. Taken together, It seemed that our results could be developed as one of an eco-friendly practical measures useful for alleviating Ulva bloom in the future.