• Ocean and Polar Research
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• v.25 no.3
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• pp.277-286
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• 2003

Nitrification performance of fixed film biofilters using coarse sand, loess bead, or styrofoam beads in biofilter columns 1 meter high and 30cm in diameter were studied at different hydraulic and organic matter loading rates. Synthetic wastewater was supplied to the culture tank in order to maintain desired TAN concentrations in inlet water to biofilters. All the biofilters were conditioned 5 months before start of sampling. TAN and $NO_2-N$ conversion rates increased with an increase in the hydraulic loading rate (HLR). However, the improvement in biofilter performance was not linearly correlated to HLR in styrofoam bead filters. This is mainly due to the characteristics of the styrofoam beads used. TAN conversion rates of sand filters increased with the increase of HLR up to $200m^3/m^2$. per day. No increase in the TAN conversion rate was observed at the highest HLR since flooding on the media surface took place. HLR had a significant impact on the TAN conversion rates in loess bead filter up to the highest HLR tested (P<0.05). TAN conversion rates were much less at organic matter loading rates of 9 and 18kg $O_2/m^3$ per day than those without the addition of organic matter in styrofoam bead filters. The addition of glucose resulted in a reduction of the TAN conversion rate from 540 to 284g $TAN/m^3$ per day. No significant difference of TAN conversion rates between the two organic matter loading rates was found (p<0.05). This indicates that the impact of organic matter on nitrification becomes less and less sensitive with an increase in the COD/TAN ratio. At an organic matter loading rate of 9kg $O_2/m^3$. per day, a great reduction of TAN conversion rates was observed in sand filters and loess bead filters. Clearly, organic matter can be one of the most Important Impacting factors on nitrification. $NO_2-N$ conversion rates showed a similar trend for TAN. Based on the TAN and nitrite conversion rates, styrofoam beads showed the best performance among the three filter media tested. Also, the low gravity and price of styrofoam beads make the handling easier and more cost-effective for commercial application. The results obtained at the highest organic matter loading rates can be used in the biofilter design in recirculating aquaculture system.

• The Korean Journal of Financial Management
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• v.21 no.1
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• pp.87-124
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• 2004

Some studies indicate that investors systematically underreact to new information in the stock market and Other studies indicate that investors systematically overreact. If investors irrationally react to the R&D intensity information, The portfolio strategy based on the R&D intensity information will be provided substantial excess returns. This study investigate that investors systematically underreact or overreact to the R&D intensity and whether portfolio strategy based on the R&D intensity is useful or not. Major results we as follows. First, This study indicate that investor systematically underreact to high R&D intensity and overreact low R&D intensity information. Second, after controlling the firm's specific factor such as firm size, BV/MV and past price performance, it is found that the performance of portfolio strategy based on the R&D intensity is not significant.

• The Korean Journal of Financial Management
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• v.24 no.3
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• pp.29-62
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• 2007

We examine the methods to increase MBS values given parameters of default risks of individual mortgages and their correlation, and analyze the effects of these parameters on the efficiency of the methods. First, the values of MBS can be improved when they are comprised of low-correlation mortgages regardless of specific forms of investors' utility functions. Second, the values of MBS can also be raised even after their components mortgages are determined. More specifically, when investors' utilities are heterogeneous, CMO's of a less risky tranche and a riskier tranche are highly valued compared with pass-through securities of two identical tranches. When investors' utilities are homogeneous(risk averse), however, the latter meets the needs of investors better than the former does. Third, it can be shown that the efficiency of the methods in this paper is an increasing function of default risks of mortgage loans or of the correlation between them, and a decreasing function of the amount of the price fall of MBS when in default.

• The Korean Journal of Community Living Science
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• v.20 no.3
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• pp.397-411
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• 2009

The use of local product foods and fresh-cut products, the dietitian's recognition, the required items and the quality for school foodservice was investigated to increase the consumption of high-quality agricultural products. Data from 578 elementary schools, 228 middle schools and 116 high schools were collected by school foodservice personnels in each regional Education Administration in Gyeong-gi province. The first criteria of buying food materials was reliability/safety for all school foodservice. The second criteria were the origin of the product and freshness/ripeness for elementary and middle schools and high school, respectively. The most important consideration for selecting a supplier was the quality of the material. The appearance/status of the food was the first factor for buying food materials. The origin and the seasonality were very important for buying farm products. Dietitians in Gyeong-gi province recognized the local products, and used them weekly. The advantages of using local products were the quick supply, freshness and safety. On the other hand, the disadvantages were the lack of information and the uncertainty of supply. Sixty eight percent of the subjects had experienced the high-quality agricultural products in school meals, but the frequency was low. The main reasons for not servicing high-quality agricultural products were the high cost and the lack of trust on the quality. Among fresh-cut products, seasonings and root vegetables were purchased most frequently, but leaf vegetables was 5.7% only. The purchase of fresh-cut products was not frequent, but usually satisfied. The advantages of fresh-cut products were the reduced workload and waste, but the reason for not using them were poor hygiene and the high price. The diverse supply system and the promotion of the local product foods would be necessary since the most food materials were purchased through suppliers. In addition, the problems related to the high cost and distrust should be resolved to expand the consumption of the high-quality agricultural products and the fresh-cut vegetables. The institutions for certifying the quality should be needed to increase the confidence of these products.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.12
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• pp.71-75
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• 1972

To investigate the effects of C. E. P. A(2-chloroethyl phosphonic acid) on the ripening of tobacco leaf, the effects on the yield and quality of leaf tobacco, this experiments were carried out during the period of from 1970 to 1971 at tobacco experiment station, Sosa, Korea and 3 locations. The results are summarized as follows. 1. The higher the C. E. P. A concentration was, the more the leaf ripening was accelerated. During the period from 3 to 4 days after treatment, the differences of leaf ripening among levels were prominent. 2. Treatment with C. E. P. A only on the upper surface of the tobacco leaf, accelerated the ripening of that particular part treated, but not apparently the other parts of leaf. 3. Distinctive acceleration of leaf ripening was, obserbed in the fully develope1lower leans, however, the upper leaves were indistinctive. 4. The higher C. E. P. A concentration was, the more the effect of ripening acceleration was. But the yield was reduced over 900ppm because of the low of growth of leaves and the reduced yield was 90% at the 3, 000ppm. So the proper concentration was regarded as 900ppm. 5. In the view point of the days of C. E. P. A ripening acceleration, it was shortened one days at 100 ppm, three days at 300ppm, three days at 450ppm, four days at 900ppm, seven days at 3, 000ppm. 6. In the point of curing process, it was possible that the curing time and fuel was reduced 29% and 45% respectively in the C. E. P. A treatment than the check. 7. Therefore, if it is treated the C. E. P. A at 900ppm in the tobacco cultivation, the quality shall be increased 13.5% and the price shall be increased 12% in the 10 Are. In the point of subsidiary affect, it is possible that the C. E. P. A ripening acceleration is shortened about 7 days at 3, 00ppm and curing time is shortened about 24 hours.

• Journal of Distribution Science
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• v.13 no.7
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• pp.85-90
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• 2015

Purpose - Global trends play a part to change the structure of the fashion industry. In particular, companies attempting to conduct innovative marketing centering on such products as SPA brands are growing into global companies. SPA stands for "Specialty Store Retailer of Private Label Apparel", meaning its activities are fully integrated from manufacturing through sales, including material procurement design, product, distribution, inventory management, and final sales. For this reason, more understanding of individual corporate profitability is very sensitive to consumer's attitudinal changes. The effects that corporate marketing activities on customer lifetime value through brand attitude were analyzed based on a structural equation model. Rust suggested value equity, brand equity, and relationship equity as customer equity driver. The study examines Chinese consumer because China is the fastest growing fashion market in the world. Research design, data, and methodology - The survey targeted Chinese college student age 20s. Only respondents who had purchased SPA brands in the past year were included for this research. A total of 303, except for 47 missing data of 350 distributed questionnaires were included in this research. The questionnaire is consists of six part to measure value, brand, relationship equity, attitude toward brand, purchase intention and demographic characteristics. This research conducted exploratory factor analysis and reliability test. To verify research hypotheses, structural equation model test was conducted. As for customer equity, diversified models in consideration of the scope of acquisition data, a method of collection of data, influencing factor, and predictability were suggested based on a net present value model. However, the history of customer equity study is relatively short, and sufficient empirical analyses have not been conducted, so more integrated analysis is required. In this study, the concept of driver suggested by Rust was applied to figure out the effects that consumer's attitude has on customer equity. The customer equity driver suggested by them consists of brand equity, value equity, and relationship equity. Results - This study reveals that value equity and brand equity have a positive influence on relationship equity. And, relationship equity has a positive influence on purchase intention through brand attitude. However, value equity and brand equity do not influence on brand attitude. Conclusion - The results of this research generated following implications. First, SPA brands need to take advantage of their value equity such as perceived low price and up-to-date fashion style to attract Chinese young consumer. Second, strong brand equity promises dominants position in the competitive market. As Chinese fashion market grows rapidly, SPA brands can consider branding strategy such as flagship store and celebrity marketing enhancing brand image. Third, the core concept of customer equity strategy is to maintain a relationship with their expecting and existing customers. The relationship equity is built by brand equity and value equity. When SPA brands serves product and service meet with individual customers, customers have intimacy to the brands.

• Journal of Distribution Science
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• v.12 no.12
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• pp.107-118
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• 2014

Purpose - Due to the recent slowdown of growth in global luxury brands, which have been an engine of our domestic fashion market growth, there is an increasing need to develop a global market for domestic high-priced fashion brands. In spite of the large scale of trade between Korea and China with respect to fashion products, current trade concentrates on middle- and low-priced products rather than high-priced products. Diversification of the trade between Korea and China in terms of the price levels of trade products is needed. An understanding of Chinese consumption values and purchase intentions for luxury fashion brands will be very helpful for the establishment of strategies with the aim of increasing the level of trade with regard to high-priced fashion products. Therefore, the study aimed to identify the differences in the clothing consumption values of South Korean and Chinese women in their 20s, especially with reference to how those values affect their preference and purchase intention for luxury fashion brands. Research design, data, methodology - The study was implemented through a descriptive survey method using a self-administered questionnaire. The sample consisted of 283 Korean and 306 Chinese women in their 20s, residing in Seoul, Beijing, Guangzhou, and Shanghai. Data were collected from March 3 to 15, 2014. A total of 589 completed responses were analyzed. Data were analyzed by factor analysis, t-test, and multiple regression analysis. Results - Fivefactors for clothing consumption values were formulated: conspicuous/social value, fashionability value, personality expression value, hedonic value, and practical value. There were significant differences between Korean and Chinese consumers in clothing consumption values (except social value), preference, and purchase intention for luxury fashion brands. With regard to clothing consumption values, Chinese women attached more importance to fashionability value, personality expression value, hedonic value, and practical value than South Korean women. In addition, Chinese women's preference and purchase intention for luxury fashion brands were higher than South Korean women's. Second, in the case of South Korean women, social value, practical value, and fashionability value had positive effects on preferences for luxury fashion brands, while attractive/personality expression value and hedonic value had no influence. In contrast, in the case of Chinese women, social value and fashionability value had positive effects on preference for the luxury fashion brands. Third, in the case of South Korean women, social value and practical value had positive effects on purchase intentions for luxury fashion brands. In contrast, in the case of Chinese women, social value, personality expression value, and fashionability value had positive effects on purchase intention for luxury fashion brands. Conclusions - Considering the findings of the study, it is clear that differentiated marketing strategies are needed for luxury fashion brand markets in Korea and China. The results of the study could provide useful information that will help increase the effectiveness of luxury fashion brand marketing strategies in Korea and China.

• Journal of Digital Convergence
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• v.18 no.2
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• pp.197-204
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• 2020

The purpose of this paper is to find the direction by analyzing the synchronization phenomenon and the change rate of apartment charter rate in Korea, Seoul, Busan, Daegu, Gwangju and Daejeon. For this purpose, this study used a total of 239 monthly data from January 2000 to November 2019 in Kookmin Bank housing statistics. In the correlation analysis, Korea showed the highest relationship in order of Seoul, Busan, Incheon and Daegu. Seoul showed a low figure of 0.3 without any distinctive features from other cities. On the other hand, Busan, Daejeon and Daegu showed high correlations. As a result of the regression analysis, Korea and 5 major cities were all moving in the same direction with positive(+) values. And Busan and Seoul responded significantly to Korea. In the shock response, Korea is most shocked by the change in Seoul. Daegu is relatively shocked by Busan and Daejeon. Seoul's charter rate has declined most strongly in the last three years. Therefore, it is time to be careful not to incur losses due to gap investment. If we look at the relationship between the charter rate and the sale price in future studies, we can better understand the Korean apartment market.

• Journal of Plant Biotechnology
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• v.29 no.4
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• pp.223-228
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• 2002

We have developed a homemade particle inflow gun (PIG) system which has simple operation method, low price and high gene introduction efficiency into rice callus. Rice callus were inflowed with gold particles containing DNA of a plasmid, pIG121Hm, harboring intron GUS ($\beta$-glucuronidase) gene, NPTII gene and HPT gene. For optimal GUS transient expression, the effects of parameters on DNA delivery efficiency of the PIG system was investigated by scoring transient GUS expression. The highest number of blue spots was observed at 16 mM of spemidine and 1.5 M of calcium chloride, respectively. And the amount of gold particles required for the best GUD expression was 2 mg. Optimum GUS transient expression was observed at target distance of 12 cm and helium pressure of 3.5 bar (50 psi). Gene introduction efficiency of the PIG system was observed almost similar to that of the Biolistic Gun (Bio-Rad Company). Since PIG system is simple to operate and one doesn't need disposable accessaries, the PIG system can be easily applied to various replication experiments.

• Journal of Mushroom
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• v.8 no.1
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• pp.11-15
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• 2010

The word spawn is derived from an old French verb, espandre, meaning to spread out or expand. Spawn is also defined as "the mycelium of fungi, especially of mushrooms grown to be eaten, used for propagation". The effects of bag spawn to sawdust substrate on the growth of Pleurotus ostreatus were conducted. The duration of mycelial growth and days of pinhead formation of bag spawn(2.5kg) were 18~19days and 7~8days, whereas bottle spawn ($1,000m{\ell}$) was 18days and 6days, respectively. The yield of mushroom fruitbody was that bag spawn is 100~118g, bottle spawn is 95~115g. In economical analysis, bag spawn is increased to 50%, compared to bottle spawn in relative income.