• Journal of Korean Society for Atmospheric Environment
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• v.13 no.1
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• pp.9-18
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• 1997

Precipitation samples were collected by the wet- only event sampling method from Seoul during September 1991 to April 1995. These samples were analyzed for the concentrations of the major ionic components (N $O_3$$^{[-10]}$ , N $O_2$$^{[-10]}$ , S $O_4$$^{2-}$, C $l^{[-10]}$ , $F^{[-10]}$ , N $a^{＋}$, $K^{+}$, $Ca^{2＋}$, $Mg^{2＋}$, and N $H_4$$^{＋}$), pH, and electric conductivity. During the study period, a total of 182 samples were collected, but only 163 samples were used for the data analysis via quality assurance of precipitation chemistry data. The volume-weighted pH was found to be 4.7. The major acidifying species from our precipitation studies were identified to be non-seasalt sulfate (84$\pm$9 $\mu$eq/L) and nitrate (24$\pm$2 $\mu$eq/L) except for chloride. Because the Cl/Na ratio in the precipitation was close to the ratio in seawater. If all of the non-seasalt sulfate and nitrate were in the form of sulfuric and nitric acids, the mean pH in the precipitation could have been as low as 3.7 lower than the computed value. Consequently, the difference between two pH values indicate that the acidity of precipitation was neutralized by alkaline species. The equivalent concentration ratio of sulfate to nitrate was 3.5, indicating that sulfuric and nitric acids can comprise 78％ and 22％ of the precipitation acidity, respectively. Analysis of temporal trend in the measured acidity and ionic components were also performed using the linear regression method. The precipitation acidity generally showed a significantly decreasing trend, which was compatible with the pattern of the ratio (N $H_4$$^{＋}$＋C $a^{2＋}$)/ (nss-S $O_4$$^{2-}$＋N $O_3$$^{[-10]}$ ).).

• Korea journal of population studies
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• v.10 no.2
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• pp.1-16
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• 1987

This work examines reemployment processes through the use of event history unemployment data in the United States. Two aspects of these processes, the duration of unemployment and changes in the reemployment rate, are modelled and analyzed in terms of individual characteristics and their structural positions in the labor market. The secondary labor market is a competitive market in which unemployment occurs because people quit their jobs to devote more time in search for better jobs. Using search theory, the rate of reemployment has a positive time dependence as the searcher lower her reservation wage with the passage of time. By contrast, the primary market is characterized by long-term employment relations which reduce voluntary turnovers but generate layoffs temporarily. Relying on contract theory, because workers on temporary layoffs wait for recall, reemployment rates have a constant time dependence. Empirical results of unemployment durations indicate that reemployment processes are influenced by individual's positions in dual labor market structures. While the analysis suggests that the amount of search reemployment seems to be positively related to the degree of competitiveness of a market, somewhat weaker results are noted in the search reemployment processes in competitive markets.

• Journal of the Korean Society of Costume
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• v.60 no.8
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• pp.100-117
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• 2010

The cosmetics industry is executing the experiential marketing strategy, which focuses the brand experiential experience for the connection with consumers and differentiated strategy for the company's brand image, according to the expansion of quality service, which increasingly consume a diverse experience. Among these, the low-priced cosmetics market is trying a variety of experiential marketing to provide positive experience of their product and their brand through a unique service or event to stimulate the motions of young woman, who are changing rapidly, and is actively utilizing the means of marketing to form brand equity for these experiential marketing. Therefore, this study is to find out the effect of customer experiential on the brand equity through a variety of experiential marketing of low-priced cosmetics brand and based on the result, we were able to find out that the experiential marketing is also used as important means of marketing for low-priced cosmetics market to secure the brand equity and to maintain long-term relationship with the customer. This is expected to provide strategic and practical implications to the cosmetic marketing managers for customer management and this will recognize the importance of customer experiential in cosmetic marketing and suggest proper marketing strategy plan. In this study, the multiple regression analysis was mainly uses to find out the influence between the variables for low-cost cosmetic brand but we're hoping to execute a study, which directly and indirectly covers the complete path by using the various parameters, which can be effected on the brand equity.

• Cartoon and Animation Studies
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• s.24
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• pp.83-105
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• 2011

The term "ya-o-ii" which is referred as a homosexual comics in Korea came from Japan and it became one of popular genres in both Japan and Korea's comics market. People create yo-o-ii with their own idea or borrow male characters from the pre-existed comics or animation and create a whole new story. Homosexual comics which is based on teenage readers deals with sex and focuses on homosexuality. For that reason it reflects social phenomenon than general material for comics. Before we focus on influence of homosexual comics on teenagers and social phenomenon, this study is for fundamental understanding on homosexual comics itself. In order to look into current state of homosexual comics, the survey was conducted at "Comic World" which is well known as the biggest offline comic event in Korea. This study analyzes range of age and awareness of readers of homosexual comics on the basis of the survey. Hopefully, this study helps better understand an influence of homosexual comics on teenage readers with problem of sex identity and contribute to the study of market segmentations of homosexual comics.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.1
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• pp.17-29
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• 2013

Long-Term Hydrologic Impact Assessment (L-THIA) model which is a distributed watershed model was applied to analyze the spatial distribution of surface runoff and nonpoint source pollutant loading from Imha watershed during 2001~2010. L-THIA CN Calibration Tool linked with SCE-UA was developed to calibrate surface runoff automatically. Calibration (2001~2005) and validation (2006~2010) of monthly surface runoff were represented as 'very good' model performance showing 0.91 for calibration and 0.89 for validation as Nash-Sutcliffe (NS) values. Average annual surface runoff from Imha watershed was 218.4 mm and Banbyun subwatershed was much more than other watersheds due to poor hydrologic condition. Average annual nonpoint source pollutant loading from Imha wateshed were 2,295 ton/year for $BOD_5$, 14,752 ton/year for SS, 358 ton/year for T-N, and 79 ton/year for T-P. Amount of pollutant loading and pollutant loading rates from Banbyun watershed were much higher than other watersheds. As results of analysis of loading rate from grid size ($30m{\times}30m$), most of high 10 % of loading rate were generated from upland. Therefore, major hot spot area to manage nonpoint source pollution in Imha watershed is the combination of upland and Banbyun subwatershed. L-THIA model is easy to use and prepare input file and useful tool to manage nonpoint source pollution at screening level.

• Journal of Labour Economics
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• v.27 no.3
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• pp.75-111
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• 2004

On the basis of data from the National Longitudinal Survey of Youth (NLSY), this paper investigates wage consequences of cumulative experience of job displacement. Unlike previous studies, we consider two measures of cumulative unemployment experience simultaneously: the total frequency and the cumulative duration of unemployment induced by job displacement. When frequency and cumulative duration compete in a wage equation, only cumulative duration remains significant for men, while only frequency matters for women. For men, a one-month increase in the cumulative duration of displacement-initiated unemployment leads to a fall in wages by 0.4 percent. This finding is quite robust with respect to various sample restrictions and/or estimation methods. For women, approximately a 2.5 percent wage reduction is associated with an additional event of displacement.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.2
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• pp.102-107
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• 2007

A remarkable sea surface cooling (SSC) event was observed in the eastern sea of Korean peninsula based on new generation sea surface temperature (NGSST) satellite images in September 2005, when typhoon Nabi passed over the East Sea. The degree of SSC ranged from $1^{\circ}C\;to\;4^{\circ}C$, and its maximum was observed in the southeastern sea area. Daily variations in sea surface temperature at a longitudinal line $(35^{\circ}-41^{\circ}N,\;132^{\circ}E)$, derived from satellite data for September 1-13, 2005, showed that the SSC lasted about 3 days after the typhoon passed in the south of $39^{\circ}N$, whereas it was unclear in the north of$39^{\circ}N$. Water temperature measured by a mooring buoy suggested that the SSC was caused mainly by a vertical mixing of the water column driven by the typhoon, rather than by coastal upwelling.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.1
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• pp.1-14
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• 2009

Wind energy has been recognized as one of the most important and fastest growing energy resources without emission of air pollutant. Thus, it is necessary to predict wind speed and direction accurately both in time and space toward the efficient usage of wind energy. Numerical simulation experiments using the Fifth-Generation Mesoscale Model (MM5) are carried out to clarify the impact of surface observation data assimilation on the estimation of wind energy resources. The EXP_Radius run was designed with respect to the radius of influence in the Four-Dimensional Data Assimilation (FDDA), and the EXP_Impact run was made by changing the nudging coefficient that determines the relative magnitude of the nudging term. The simulation period covers a clear-sky event on 3 - 5 June 2007 and another is on 2 - 4 December 2006. It is found that the simulated results are very sensitive to the radius of influence and nudging parameters in the FDDA. The further analysis of the results shows that the impact of the radius of influence tends to be stronger in weak synoptic flow episode than that in strong synoptic flows episode. The nudging factor is also sensitive to the intensity of the synoptic flows.

• Journal of Korean Society of Water and Wastewater
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• v.34 no.5
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• pp.335-344
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• 2020

Due to global climate change, mega-droughts have occurred frequently. Since long-term droughts make it difficult to secure the water resources, water supply needs to be restricted in a reasonable manner. In the event of limited water supply, the waterworks need to develop a restricted water supply strategy. This study showed that analyzing daily water supply could be used to respond to the first stage of a drought. According to an analysis of Korea's major water authorities, there was about 7~21% of room for daily minimum water supply in case of a drought. Restricting the water supply by lowering pressure is a good strategy for local water authorities with high water leakage rate since leakage is inversely dependent with pressure. For this method, it is necessary to quantify water deficiency and pressure at each node using a simulation. Since DDA-based software is not possible to predict changes in demand at nodes with pressure reduction, WaterGEMS, a PDA software, was used to quantitatively predict water shortages and pressures at each node. Locations where water is deficient need to install booster pumps or to be dispatched with water tank truck and bottled water. Without these support, lowering pressure could not be an option for water works. This paper suggests a method for waterworks to plan a drought by lowering pressure to restrict water supply using daily water supply analysis and PDA based simulation.

• Journal of Korean Elementary Science Education
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• v.32 no.3
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• pp.327-345
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• 2013

This study aims to investigate how pre-service elementary school teachers understand 'something scientific', 'being scientific', 'scientific events' and 'scientific questions' through semantic network analysis. To achieve this purpose, this study carried out a central analysis of the frequency and density of words and the degree of connection between key words, a concentric analysis, a click analysis and a common network analysis through text semantic network analysis by using NetMiner 4.0 Program. Based on the results of these analyses, this study came to the following conclusions. Firstly, in perceiving 'something scientific', pre-service elementary school teachers recognized 'verification', 'objective' and 'experiment' as most important words. In other words, they perceived that main grounds for something scientific should be provided through clear facts, possible to be verified and accompanied by an exact and logical theoretical system. In regard to 'being scientific', they perceived 'explanation', 'objective' and 'verification' as most important words, while having a traditional point of view that science is a set that can be explained objectively. Secondly, in regard that the term, 'observation', is contained in 'scientific events', they showed a high rate of understanding it as a scientific event. In regard to scientifical reasons, they showed the highest frequency of 'observation', and for unscientific reasons, they showed the highest frequency of 'behavior'. In perceiving 'scientific questions', they showed the highest frequency of determining bacteria-related questions as scientific. As a reason why they thought as scientific, they mentioned 'observation' most frequently like 'scientific events', while mentioning 'value judgement' as a reason why they thought as unscientific most frequently. From the results of integrated network analysis, this study found out that words pre-service teachers commonly used in stating scientific events or scientific questions were overlapped with words they mentioned for scientific events or scientific questions. As a result, it was found there were many pre-service teachers having interpreted scientific words without clearly distinguishing scientific events or scientific questions.