• Korean Journal of Microbiology
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• v.45 no.2
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• pp.112-118
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• 2009

Ammonia-oxidizing bacteria (AOB) are chemolithoautotrophs that play a key role in nitrogen removal from advanced wastewater treatment processes. Various AOB species inhabit and their community compositions vary over time in the wastewater treatment bioreactors. In this study, a hypothesis that operational and environmental conditions affect both the community compositions and the diversity of AOB in the bioreactors was proposed. To verify the hypothesis, the clone libraries based on ammonia monooxygenase subunit A were constructed using activated sludge samples from aerobic bioreactors at the Pohang, the Palo Alto, the Nine Springs, and the Marshall wastewater treatment plants (WWTPs). In those bioreactors, AOB within the Nitrosomonas europaea, N. oligotropha, N.-like, and Nitrosospira lineages were commonly found, while AOB within the N. communis, N. marina, and N. cryotolerans lineages were rarely detected in the samples. The AOB community structures were different in the bioreactors: AOB within the N. oligotropha lineage were the major microorganisms in the Pohang, the Palo Alto, and the Marshall WWTPs, while AOB within the N. europaea lineage were dominant in the Nine Springs WWTP. The correlations between the AOB community compositions of the wastewater treatment bioreactors and their operational (HRT, SRT, and MLSS) and environmental conditions (temperature, pH, COD, $NH_3$, and $NO_3{^-}$) were evaluated using a multivariate statistical analysis called the Redundancy Analysis (RDA). As a result, COD and $NO_3{^-}$ concentrations in the bioreactors were the statistically significant variables influencing the AOB community structures in the wastewater treatment bioreactors.

• Asia-Pacific Journal of Business
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• v.6 no.2
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• pp.81-95
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• 2015

This study is an investigative study into the effects that the 'travel motivations' of participants on walking tourism has on their 'degree of satisfaction' by identifying tourist motivations for selecting walking tour among many types of tourism and their effects on hikers' degree of satisfaction. This study was conducted with hikers affiliated with 'walking on beautiful roads '-one of Busan's preliminary social enterprises- with a total of 176 copies used for a final effective sample. Data collected was analyzed using SPSS WIN 18.0 to conduct a frequency analysis of the sample. Along with exploratory factor analysis, Cronbach's ${\alpha}$ coefficient was used as an estimate of the validity and reliability of each factor. Multiple regression analysis was done for an analysis of travel motivations and their effects on satisfaction. The scale rates items in the questionnaire in the following categories: 'Motivations' for walking tours consist of 5 factors- vacation, soul-searching, social get-togethers, nature tour, community experience-with a total of 20 items. 'The degree of satisfaction' is made up of a factor with a total of 4 items. The results of the study are as follows: with respect to the hypothesis that motivations for walking tour would have a positive effect on the degree of satisfaction, test results show that 'motivations' have significant partial effects on the 'degree of satisfaction'. Motivations affect the degree of satisfaction in the order of nature tour and soul-searching except for experience and social get-togethers- an indication that participants on walking tours tend to travel for the attractiveness of nature, wanting time for reflection and meditation. As the first investigative study into participants in walking tours products offered by travel agencies, the study has the following implications for marketers: First, travel agencies selling walking tour products and government institutions concerned about the development of hiking trails need to discuss ways to make the most of natural resources as they are- rather than using development-oriented approaches. The study has its own limitation: it is that with the lack of domestic and international studies on walking tours, the study has not gained access to precedent studies on the subject so it has not established a systemic approach to the emerging type of tourism. Hopefully, this study will make a small contribution to its development.

• Journal of KIISE:Databases
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• v.35 no.6
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• pp.505-517
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• 2008

This paper proposes a rewriting algorithm of OWL-DL ontology query in SPARQL. Currently, to obtain inference results of given SPARQL queries, Web ontology repositories construct inference ontology models and match the SPARQL queries with the models. However, an inference model requires much larger space than its original base model, and reusability of the model is not available for other inferrable SPARQL queries. Therefore, the aforementioned approach is not suitable for large scale SPARQL query processing. To resolve tills issue, this paper proposes a novel SPARQL query rewriting algorithm that can obtain results by rewriting SPARQL queries and accomplishing query operations against the base ontology model. To achieve this goal, we first define OWL-DL inference rules and apply them on rewriting graph pattern in queries. The paper categorizes the inference rules and discusses on how these rules affect the query rewriting. To show the advantages of our proposal, a prototype system based on lena is implemented. For comparative evaluation, we conduct an experiment with a set of test queries and compare of our proposal with the previous approach. The evaluation result showed the proposed algorithm supports an improved performance in efficiency of the inferrable SPARQL query processing without loss of completeness and soundness.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.6
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• pp.474-481
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• 2011

The discharge coefficient and spatial velocity distribution were clarified by carrying out a physical experiment to assess the performance of sluice for tidal power generation. The physical experiment was performed by manufacturing 10 sluce models whose scale is 1/70 of the prototype and installing it in the planar open channel, which has apron sections in front of and behind the sluice models. In particular, it was attempted to reasonably determine the locations and method of measuring water levels that may affect estimation of the discharge coefficient. Based on the experimental results for various conditions of discharges and tidal levels, the discharge coefficient of the sluice in the experiment was estimated as 1.3 to 1.4. Meanwhile, it was found that velocities were 2~3% faster at the sluices near the central region whereas 4~5% slower at the sluices on both sides, in comparison to the average value of the mean velocities of the ten sluices.

• 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.

• The Journal of Industrial Distribution & Business
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• v.9 no.6
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• pp.57-64
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• 2018

Purpose - With the rapid economic development, great changes have happened in the Chinese beer market. The scale of imported beer is increasing. However, the sales of native Chinese beer decrease in recent years. It is because more Chinese customers prefer beer with unique attributes than those with lower prices. In order to take an advantage in this market, practitioners should develop new products to satisfy Chinese customers. Scholars have also focused on beer characteristics to estimate consumers' behavior for improving the development of beer industry. However, most studies are theoretically centered on marketing strategy management or general understanding of the market. It is not enough for us to explain customers' consumption patterns. Some empirical research did attempt to find out beer attributes that may influence their choice behavior. However, they failed to verify what can increase customers' utility through a new product. More importantly, few evidences can be found in the literature. Therefore this study explores the major characteristics of imported beer which may associate with customers' preferences. Research design, data, and methodology - With the results of literature review and focus group interview, we found out four main imported beer attributes and the levels of each factor. A pre-test is constructed to check the problems in the questionnaire protocol. With the results of pre-test, the revised questionnaire is processed among customers who have purchased and had imported beer in China regions such as Beijing, Shanghai, Jiangsu, Guangdong and so on. The choice-based conjoint analysis is applied to analyze the useful data of 205. Results - Results indicate that choice-based conjoint analysis is the effective method to estimate customers' choice behavior. Results also indicate that country of origin, price, taste, and package affect customers' preference and the importances of imported beer attributes are significantly different. Conclusions - Country of origin, price, taste, and package are important for customers to make an imported beer choice decision. Marketers should consider these determinants and their importance to develop new products. Moreover, choice-based conjoint analysis should be the useful method for practitioners to develop a new product of imported beer for sustainable business in the competitive industry.

• The Korean Journal of Rehabilitation Nursing
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• v.6 no.1
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• pp.51-60
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• 2003

This study was a descriptive research in search of a nursing intervention scheme to improve stroke patients' quality of life by understanding the relationship of stroke patients' ADL, depression, self-efficacy and quality of life with various variables and identifying factors that affect their quality of life. Each subject was interviewed one to one based on a structured questionnaire. With regard to research tools, Modified Barthel Index (MBI: Fortinsky et al., 1981), which was translated by Choi, Hye-sook (1996), was used in measuring ADL, Randloff's (1977) tool, which was translated by Choi, Soon-hee, was used in measuring depression, and the tool developed by Sherer et al. (1982), which is to measures self-efficacy under general conditions not limited to specific conditions, and modified by O, Bok-ja (1994) was used in measuring self-efficacy. The quality of life was measured using the scale of satisfaction of life developed by Diener et al. (1985). The results of this study were as follows: 1. The means of ADL of the subjects was $79.5{\pm}31.9$, depression $26.8{\pm}10.4$, self-efficacy $47.1{\pm}25.7$, and the quality of life $12.3{\pm}4.9$. 2. The subjects' quality of life showed a statistically significant difference according to gender (t=7.9, p= .006), satisfaction with income (F=5.8, p= .004), the burden of medical fee (F=3.7, p= .028) and the period of disease (F=2.8, p= .042). 3. With regard to relationship among ADL, depression, self-efficacy and the quality of life, ADL was in a relatively low positive correlation (r= .293, p= .003) with and the quality of life, depression in a high negative correlation (r=- .634, p= .000) with the quality of life, and self-efficacy in a positive correlation with the quality of life (r= .388, p= .000). 4. Factors that made a significant influence on the quality of life were depression (B=- .309, p= .001) and satisfaction with income (B=-2.611, p= .001). Based on these results, this study made following suggestions: 1. It is necessary to run rehabilitation programs to improve stroke patients' ADL, depression and self-efficacy. 2. It is necessary to perform research of monitoring stroke patients' quality of life in various areas using measuring tools.

• Journal of Microbiology and Biotechnology
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• v.30 no.5
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• pp.785-792
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• 2020

ʟ-Theanine, found in green tea leaves has been shown to positively affect immunity and relaxation in humans. There have been many attempts to produce ʟ-theanine through enzymatic synthesis to overcome the limitations of traditional methods. Among the many genes coding for enzymes in the ʟ-theanine biosynthesis, glutamylmethylamide synthetase (GMAS) exhibits the greatest possibility of producing large amounts of production. Thus, GMAS from Methylovorus mays No. 9 was overexpressed in several strains including vectors with different copy numbers. BW25113(DE3) cells containing the pET24ma::gmas was selected for strains. The optimal temperature, pH, and metal ion concentration were 50℃, 7, and 5 mM MnCl₂, respectively. Additionally, ATP was found to be an important factor for producing high concentration of ʟ-theanine so several strains were tested during the reaction for ATP regeneration. Baker's yeast was found to decrease the demand for ATP most effectively. Addition of potassium phosphate source was demonstrated by producing 4-fold higher ʟ-theanine. To enhance the conversion yield, GMAS was additionally overexpressed in the system. A maximum of 198 mM ʟ-theanine was produced with 16.5 mmol/l/h productivity. The whole-cell reaction involving GMAS has greatest potential for scale-up production of ʟ-theanine.

• Journal of Korean Foot and Ankle Society
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• v.22 no.1
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• pp.21-25
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• 2018

Purpose: To analyze the correlation between a rupture of the hypovascular zone and early single heel raising after Achilles tendon repair. Materials and Methods: From January 2012 to August 2015, 68 patients, who underwent surgical treatment for a Achilles tendon rupture using Krackow method, were analyzed retrospectively. The patients were divided into two groups according to possibility of single heel raises within 3 months postoperatively. During the periodic outpatient observations, the visual analogue scale, Achilles tendon total rupture score (ATRS), and timing capable single heel raises were evaluated. In addition, the preoperative defect size and distance between the calcaneal osteotendinous junction and the rupture site were measured by ultrasound in all cases. Results: Twenty-three patients could perform a single heel raise within 3 months after surgery (early single heel raise group), and fortyfive patients could perform a single heel raise after 3 month postoperatively. The age, gender, body mass index, smoking, and operation delay were similar in the two groups. In addition, the defect size and distance between the calcaneal osteotendinous junction and rupture site as measured by preoperative ultrasound were similar (p=0.379 and p=0.631, respectively). On the other hand, when the rupture site was divided into the hypovascular zone (4~7 cm from calcaneal osteotendinous junction) and non-hypovascular zone, the hypovascular zone rupture rate was significantly lower in the early single heel raise group (60.9%, 14/23; 91.1%, 41/45; p=0.003). In logistic regression analysis, the odds of the hypovascular zone rupture group being capable of early single heel raise were 0.189 (p=0.017). The ATRS score at 3 months and 1 year after surgery were significantly higher in the early single heel raise group (p<0.001). Conclusion: Achilles tendon rupture at the hypovascular zone is a poor prognostic factor for early single heel raise and might affect the prognosis significantly after an Achilles tendon rupture operation.

• Journal of Preventive Medicine and Public Health
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• v.29 no.1 s.52
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• pp.51-65
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• 1996

The purpose of this study was to examine the trends of length of hospital stay (LOS), which is most likely to be a major attribute to hospital performance. From 1984 to 1994, an average LOS of each hospital was analyzed by factors such as medical departments, bed size, occupancy rate, region and ownership. This study was analyzed changing rate of LOS during 11 years. This rate was calculated by simple regression, which was used only with hospital without missing data during 11 years. This study findings are as follows. 1. The results indicated that the average LOS was steadily increased until 1990 but it was slightly decreased after 1990. 2. This trend could be found in all hospital scale and all group of occupancy rate. Specifically this trends of LOS were found in internal medicine, corporate owned hospitals, and hospitals in major city. But LOS of individual owned hospital was continuously increased until 1994. 3. Means of changing rates of LOS were calculated from 1984 to 1994. If we devided it into two parts, before 1990 and after 1990, most changing rates of LOS before 1990 except individual owned hospital were found positive sign. The changing rates after 1990 were negative sign but small hospital(lesser then 200 bed), individual owned hospital, national & public hospital and hospital in small urban have little change of LOS after 1990. Finally from this results we thought that most hospitals in Korea began to be concerned with LOS. Nevertheless LOS of several hospital such as small hospital or individual owned hospital was increased. And this trend may be caused by a few patients, low occupancy rate, or low profit. This trend of LOS is different from that of other countries. Perhaps this phenomenon is resulted from the reimbursement method. Because of fee for service reimbursement system in Korea the hospitals didn't need to shorten LOS in order to save the cost and increase the profit. Therefore reform of hospital cost reimbursement method will be needed to reduce hospital cost in Korea. We thought that the Korean health authority should consider the reimbursement method by unit of bundle of services, for example DRG and prepayment in the United States. This study presents some limitations such as no insight of severity of disease, case-mix measurement of hospital, and other clinical characteristics that can. possibly affect LOS. However, this study reports an important trend in LOS from 1984 to 1994.