• Korean Journal of Ecology and Environment
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• v.33 no.4 s.92
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• pp.366-373
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• 2000

Toxin production and low digestibility of cyanobacteria are known to cause low exploitability of cyanobacteria by zooplankton. In this study, we compared relative tolerance and compatibility of zooplankton taxa in eight eutrophic lakes, exposed to frequent cyanobacterial blooms, uring the summer season of 1999. Microcystis, Anabaena, Oscillatoria and Phormidium were common cyanobacteria in all lakes. with relatively lower $NO_3-N$ concentration (<0.2 mgN/l) and TN/TP ratio (<20), compared with other lakes where colonial cyanobacteria dominated. Rotifers were dominant zooplankton in most lakes, and among them, Keratella, Polyarthra and Hexathra were common. The laboratory feeding experiment showed that relative copepods that greatly decreased (90%) after 4 day when cyanobacteria were used as the food source of zooplankton, while rotifers gradually increased with the change of dominant taxa from Keratella through Pompholyx to Monostyla. These results suggest that rotifers may be capable of coexisting with cyanobacteria by exploiting them for the food source.

• Journal of Korean Society of Transportation
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• v.20 no.5
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• pp.113-130
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• 2002

In this paper, we developed DNL(Dynamic Network Loading) model based on Moving cell theory to analyze the dynamic characteristics of traffic flow in congested network. In this paper vehicles entered into link at same interval would construct one cell, and the cells moved according to Cell following rule. In the past researches relating to DNL model a continuous single link is separated into two sections such as running section and queuing section to describe physical queue so that various dynamic states generated in real link are only simplified by running and queuing state. However, the approach has some difficulties in simulating various dynamic flow characteristics. To overcome these problems, we present Moving cell theory which is developed by combining Car following theory and Lagrangian method mainly using for the analysis of air pollutants dispersion. In Moving cell theory platoons are represented by cells and each cell is processed by Cell following theory. This type of simulation model is firstly presented by Cremer et al(1999). However they did not develop merging and diverging model because their model was applied to basic freeway section. Moreover they set the number of vehicles which can be included in one cell in one interval so this formulation cant apply to signalized intersection in urban network. To solve these difficulties we develop new approach using Moving cell theory and simulate traffic flow dynamics continuously by movement and state transition of the cells. The developed model are played on simple network including merging and diverging section and it shows improved abilities to describe flow dynamics comparing past DNL models.

• Journal of Chest Surgery
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• v.35 no.5
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• pp.387-391
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• 2002

Background: Postoperative morbidity and mortality in destroyed lung are relatively high. We tried to identify the prognostic factors affecting postoperative morbidity and mortality in destroyed lung through a retrospective study. Material and method: The retrospective study was undertaken in 112 patients who had undergone pneumonectomy or pleuropneumonectomy for destroyed lung at Severance Hospital from 1970 to 2000. We analyzed the correlation between postoperative morbidity and mortality and etiology, duration of disease, preoperative FEV1, presence or absence of peroperative empyema, operation timing, the side of operation, duration of operation, and operation type. Result: There were 55 men and 57 women, aged 20 to 81 years (mean 44 years). Etiologic diseases were tuberculosis in 86 patients(76.8%) including tuberculos empyema in 20 and tuberculous bronchiectasis in 4, pyogenic empyema in 12(10,7%), bronchiectasis in 12(10.7%), and lung abscess in 2(1.8%). Postoperative morbidity were 25%(n=28) and postoperative mortality was 6%(n=7). The presence of preoperative empyema(p=0.016), pleuropneumonectomy(p=0.037) and preoperative FEV1 of less than 1.75 L(P=0.048) significantly increased the postoperative morbidity, If operation time was less than 300min, postoperative morbidity(p=0.002) and mortality(p=0.03) were significantly low. Conclusion: Postoperative morbidity and mortality in destroyed lung were acceptable. Postoperative morbidity and mortality were significantly low when operation time was less than 300 min. Preoperative existence of empyema, pleuropneumonectomy and preoperative FEV1 of less than 1.75 L significantly increased postoperative morbidity.

• Food Science of Animal Resources
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• v.25 no.4
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• pp.507-512
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• 2005

This study was designed to investigate the effect of $\beta-carotene$ on the heat oxidation stability of deep fried laid with different healing temperature. Commercially purchased $\beta-carotene$ was used to this experiment $\beta-carotene$ was added to the deep fried lard at final concentration of $0\%\;0.001\%\;and\;0.004\%$ (wt/wt fat basis). Total plate count peroxide value, acid value, and TBA(thiobarbituric acid) values of the samples were determined regulary at $50^{\circ}C$ during 15 days. The result of the study are as follows: The number of microorganism was decreased by $\beta-carotene$ added to the deep fried lard Deep fried lard with $0.004\%$ $\beta-carotene$ have higher antioxidative effect than those of control and $0.001\%$ treated group. Peroxide and TBA values were significantly (P<0.05) decreased in all samples by added $\beta-carotene$ at $0.004\%$ Antioxidative effect increased with increasing concentration of $\beta-carotene$. These results suggest that $\beta-carotene$ might inhibit the growth of microganisms and retard lipid oxidation in the deep fried lard.

• Journal of agricultural medicine and community health
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• v.28 no.2
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• pp.155-169
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• 2003

Objectives: The purpose of this study is to provide data for the improvement of hypertension management of community health practitioner posts through the study on hypertension management in community health practitioner posts. Methods: A questionnaire was mailed to 700 community health practitioners and 205 of them responded during the period from March 13, 2003 to May 13. The survey results were analyzed using SPSS program, version 11. Results: The results are as follows; 1. There are two major activities in a hypertension prevention project for community: health education and early detection. About 57% of community health care practitioners perform a health education for community people four times a year. The 64.5% of them used the materials for health education provided from a community health center and 22.1% of them performed a post-evaluation. The main method of early detection of hypertension was measurement of blood pressure of person to visit, which was 96.1%. Other methods included home visiting(89.3%), a referral from community hospitals and other resources(49.1%), health promotion events(39.5%), and a review of medical records(35.7%). 2. For the registration and management of patients with hypertension, about 36% of community health centers used a special form and more than 50% of them have registered patients who were managed by other health care institutions in the community. A computerized program was used for the management of patients with hypertension in 68.5% of them. More than 60% of them responded that it was used for report, treatment, and follow-up of patients with hypertension.

• Journal of Korean Home Economics Education Association
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• v.26 no.3
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• pp.35-52
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• 2014

This study analyzed the 12 different technology home economics textbooks I, II for middle school students and the content systems of the textbooks by 7 instructional strategies in Reigeluth's elaboration theory. The units analyzed were 'Clothing and self-expression' and 'Eco-friendly clothing life and recycling by reform'. The purpose of this study was to provide basic information for the development of textbooks and teaching materials by analyzing current textbooks. Researchers analyzed the textbooks individually using pre-developed analysis frame using Reigeluth's elaboration theory. The results of the study were as follows. The conceptual elaboration process was used in the unit of 'Clothing and self-expression' of all the textbooks used in this study, and procedural elaboration process was mostly used in the unit of 'Eco-friendly clothing life and recycling by reform'. The strategies of advance learning ability were presented mostly in the forms of 'Learning Objective', 'Thought Opening', 'Key terms' in either unit and sub unit. The strategies of summarizer were presented as 'Unit Summary', 'Cleanup' and 'Assessment'. The strategies of synthesizer were used in all the textbooks as the 'Exploration' to increase the students interest through the promotion of the learning content in a variety of activities and projects. The cognitive activator strategies were shown in all of the textbooks using mostly 'Figure,' and others such as 'Table,' 'Diagram', and 'Explanation of Terms'. The strategies of learner control were used to guide the supplement and deepen the learning by various forms. However the analogy strategies were hardly used in units of textbooks analyzed in this study. As a result, the technology home economics textbooks I, II for middle school students applied the Reigeluth's elaboration theory, except the analogy strategies. It is recommended to utilize th analogy strategies and various activities to enhance the students' understanding and participation.

• Journal of Korean Society of Forest Science
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• v.87 no.3
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• pp.466-474
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• 1998

This study was conducted to evaluate heavy metal concentrations(Cd, Cu, Z, and Pb) in the soil of two zinc mines and to correlate heavy metal contents between the soils and trees growing near the mines. Soils and leaves, stems, and roots of five tree species(Corylus heterophylla, Pinus rigida. Populus alba${\times}$glandulosa, Rhododendron mucronulatum, and Robinia pseudoacacia) were collected from Sambo Zinc Mine located in Hwasung and Gahak Zinc Mine in Kwangmyung city in Kyonggido. Soils near two zinc mines were not seriously contaminated by heavy metals, but Zn and Pb concentrations were at toxic level. The heavy metal concentration in soils decreased in the order of Zn, Pb, Cu, and Cd, and decreased with increasing distance from zinc mining sites. Among the five tree species, Populus alba ${\times}$ glandulosa showed the highest heavy metal concentrations in the tissue except for Pb. Particulars, leaves of the species contained the high concentrations of heavy metals to reach the maximum of 91ppm Zn. The roots of Corylus heterophylla contained high concentrations of Cu and Pb. The order of heavy metal concentrations in the tree species was Zn, Cu, Pb and Cd. The concentration of heavy metals in the tree tissues showed a positive correlation with that in soil in which trees are growing. The ratio of heavy metal concentration of trees to that of soils(concentration factor : CF) was highest in Zn and lowest in Pb. Populus alba${\times}$glandulosa had the highest CF value among the five tree species. It was concluded that Populus alba${\times}$glandulosa, based on the high metal uptake ability, could be used for decontaminating of heavy metals from contaminated soils, and Pinus rigida could be used to reflect the level of contamination in soils.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.4
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• pp.233-244
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• 2018

The purpose of this study was to improve awareness of network marketing business in South Korea, which takes a quite negative view of network marketing, to raise awareness of "starting up a business" as independent business owners, to assist them in building their own subjecthood in network business and entrepreneurial identity, and ultimately to give some suggestions on how to improve their self-directed entrepreneurial competency and the quality of their business management. To make an empirical analysis of 121 independent business owners of Korean native network marketing, the personal and background variables of the entrepreneurs were selected as independent variables, and entrepreneurship was selected as a mediator variable. The selected dependent variables were financial and non-financial business performances. A multiple regression analysis was conducted by inputting the variables. The findings of the study were as follows: It produced an effect of more financial performance when the innovation of the independent business owners of network marketing was better, and this innovation was possible to have only when they improved in entrepreneurial efficacy and locus of control. In contrast, only authenticity had an effect on boosting non-financial business performance among the factors of entrepreneurship. To have authenticity, it's necessary to strengthen achievement needs and awareness of locus of control among the personal characteristics of the independent business owners of network marketing. Among the factors of entrepreneurship, there was better authenticity when their personal networks were broader among their background characteristics. In addition, self-efficacy that was one of personal characteristics made a direct contribution to the enhancement of non-financial performance. As a result, independent business owners of network marketing are required to hold a strong belief in their own business, to be active in business activities and to have a high efficacy as spontaneous principal agents, and they also are required to have more adventurous, planned, active and propulsive achievement needs that enable them to attain the goals of their business and keep moving forward. Besides, they should foster their locus-of-control competency that is to control, endure and be responsible for a variety of phenomena or incidents that they face, and there will be better financial performance or non-financial performance only when they demonstrate their self-belief and confidence and when they have faith in and conviction about themselves. For independent business owners of network marketing, a consumer-centered thinking that entails authenticity and trustworthiness and touches the hearts of customers is a more effective marketing strategy than an egocentric thinking as sellers when they approach customers. And they are expected to make progress in terms of the quality of business management when their business attachment or enthusiasm is great enough to match their own efficacy with entrepreneurial identity or strike a balance between them.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.1
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• pp.1-12
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• 1996

This study was aimed to provide understanding on the eco-physiological response of barley tillers as affected by fertilizer application level. Yield and yield contribution rate of tillers were investigated with the data of field experiments in the former Wheat and Barley Research Institute of Suwon, Korea from September 1982 to July 1984. The 50％ and 100％ increased rates of fertilizer application were compared to the local recommendation, which is 120 - 90 - 70kg /ha for N-P$_2$O$_{5}$-K$_2$O, to examine tiller dynamics under diverse fertilization scheme. With the increased rates, more mainstem leaves appeared and more effective tillers resulted from C3, 4P, 41, 2P1 and 3PP. Higher number and yield of grains per plant were also observed in the increased rates, though the number of grains and grain yield per ear were slightly lower than the recommended rate. The order of yield contribution by various tillers with the recommended rate and 50％ increment was mainstem, 1, 2, 11, 3, 21, 12, 22, 4 and C, but 1 and 11 contributed more than mainstem and 3 with the 100％ increased rate.e.

• The Korean Journal of Malacology
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• v.19 no.2
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• pp.161-169
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• 2003

Seawater and sediment quality analysed was calculated to examinate the present environmental characteristics and pollution load was also calculated to evaluate the effect of farming area on the coastal environment. The measurements for seawater quality demonstrate the coastal environment has relatively eutrophicated with significantly decreased DO (0.2-8.5 mg/l) and elevated COD (9.6-31.2 mg/l) in summer. It was also evident that the water quality in Jindong Bay has been influenced by residues tide from Masan Bay with high metal concentration in August of 2002. Annual total pollution load (land and farm-driven) was estimated at 37,316 ton (SS) /yr: 9,809 ton/yr (26.3%) of land-driven load, 23,576 ton/yr (63.2%) of coastal sedimentation and 3,932 ton/yr (10.5%) of feces of cultural organisms. When all ark shell seedling farms are permitted species conversion to ascidian farm, the pollution load would increase by 196%, which may be another source for accelerating the eutrophication of the environment in Jindong Bay.