• Journal of The Korean Association For Science Education
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• v.38 no.3
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• pp.305-317
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• 2018

In this study, we investigated the characteristics of participant students' modeling with the blackbox simulation program and epistemic criteria. For this research, we developed a blackbox simulation program, which is an ill-structured problem situation reflecting the scientific practice. This simulation program is applied in the activities. 23 groups, 89 second year students of an education college participated in this activity. They visualized, modeled, modified, and evaluated their thoughts on internal structure in the blackbox. All of students' activities were recorded and analyzed. As a result, the students' models in blackbox activities were categorized into four types considering their form and function. Model evaluation occurred in group model selection. Epistemic criteria such as empirical coherence, comprehensiveness, analogy, simplicity, and implementation were adapted in model evaluation. The educational implications discussed above are as follows: First, the blackbox simulation activities in which the students participated in this study have educational implications in that they provide a context in which the nature of scientific practice can be experienced explicitly and implicitly by constructing and testing models. Second, from the beginning of the activity, epistemic criteria such as empirical coherence, comprehensiveness, analogy, simplicity, and implementation were not strictly adapted and dynamically flexibly adapted according to the context. Third, the study of epistemic criteria in various contexts as well as in the context of this study will broaden the horizon of understanding the nature of scientific practice. Simulation activity, which is the context of this study, can lead to research related to computational thinking that will be more important in future society. We expect to be able to lead more discussions by furthering this study by elaborating and systematizing its context and method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.2
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• pp.216-225
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• 2015

The purpose of this study was to evaluate night time eating habits, dietary habits, and nutrient intake in university students according to residence type. A survey was conducted by administering questionnaires to 664 students. Questionnaire interview and 24-h dietary recall were conducted. Subjects were divided into three groups according to residence type: dormitory boarding (DB group, N=313), self-boarding (SB group, N=246), and living with parents (LWP group, N=105). Average ages in the DB, SB, and LWP groups were 21.3, 22.2, and 22.1 years, respectively. There were no significant differences in body mass index between the three groups. In total, 77.3% of students regularly ate night time snacks. The proportion of students who reported night time eating was 84.0% in the DB group, 73.6% in the SB group, and 65.7% in the LWP group (P<0.001). In terms of food types consumed during night time eating, the DB group showed a significantly higher rate of consumption of fried chicken and flour-based foods than the SB and LWP groups, whereas the SB group showed a significantly higher rate of consumption of alcohol beverages than the DB and LWP groups. Energy, carbohydrates, protein, fat, vitamins, and mineral intakes were significantly higher in the DB group than in the SB and LWP groups. In addition, intake of cholesterol per 1,000 kcal was significantly higher in the DB group than in the SB and LWP groups. Thus, SB and DB students seemed to have more night time eating problems than LWP students. Accordingly, nutritional education is needed to support the development of healthier eating habits, in particular, night time eating habits, among students living in dormitories and in self-boarding situations.

• The Journal of Engineering Geology
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• v.23 no.4
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• pp.477-491
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• 2013

Natural radionuclides in groundwater in the Danyang area were investigated to characterize the behaviors of uranium and radon with respect to lithology and physico-chemical components, which can aid our understanding of their occurrence, properties, and origins. To this end, a total of 100 groundwater samples were collected and analyzed, and radionuclide levels were used to construct detailed concentration maps. The water type of the groundwater, assessed using a Piper diagram, is mainly Ca-Na-$HCO_3$. The concentrations of uranium range from 0.02 to $251.0{\mu}g/L$ (average, $3.85{\mu}g/L$) and only 1% exceed USEPA's MCL (Maximum Contaminant Level). Uranium is enriched in groundwaters of Cretaceous granites and Precambrian metamorphic rocks, whereas it is depleted in groundwaters of sedimentary rocks. The concentrations of radon range from 13 to 28,470 pCi/L (average, 2397 pCi/L). Only 15% of the samples exceed AMCL (Alternative Maximum Contaminant Level) of 4000 pCi/L. The radon concentration is highest in groundwater of Cretaceous granites and lowest in groundwater of sedimentary rocks. In conclusion, the distribution and occurrence of radionuclides are intimately related to the basic geological characteristics of the rocks in which the radiogenic minerals are primarily contained. The behavior of uranium is only weakly related to that of radon (correlation coefficient = 0.15). There are also weak correlations between radionuclides and the main chemical components, pH, EC, Eh, and well depth. Of note, the correlation coefficient between radon and $SiO_2$ is 0.68, and that between radon and $HCO_3$ is -0.48. Factor analysis shows that radionuclides behave somewhat independently of each other because there are no significant factors that control the behavior of chemical components as well as radionuclides. The detailed concentration maps during this study will be used to establish useful database of radionuclide distribution and geological properties throughout Korea.

• Journal of Hospice and Palliative Care
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• v.10 no.3
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• pp.128-136
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• 2007

Purpose: The purpose of this study is to investigate the current state of the home-based cancer patient management project of public health centers throughout the country. The results of the investigation is employed to identify obstacles to the execution of the program and, finally, to develop an efficient management program of home-based cancer patients. Methods: Data on the home-based cancer patient management project were collected and analyzed through visiting interviews or telephone interviews with 225 public health centers throughout the country for six months from July to December, 2006. Results: Obstacles to the present execution of the home-based cancer patient management project were identified. Some of them are : (1) patients' low trust in cancer patient management by local health centers, (2) absence of programs customized to local communities, (3) lack of personnel and vehicles for home-based cancer patient management, (4) lack of education program for personnel in charge of home-based cancer patient management, (5) problems in public health doctors, weak connection to private medical institutions, (6) absence of medical institutions and hospice facilities for cancer patients, and (7) non-standardized volunteer workers, so on. Considering all these problems, some effective management methods are proposed. The basic concept is to keep the autonomy and variety of the local helath centers. And based on this concept, three models of (1) public health center controlled model, (2) medical institutions and hospice facilities-entrusted model and (3) medical institutions and hospice facilities-cooperative model are developed. Conclusion: By adopting an adequate model among proposed three models, the public health centers are expected to achieve an efficient utilization of material resources and manpower. In addition, by inventing their own programs that are proper for the local societies, they can improve the home-based cancer patient management.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.342-353
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• 2016

This study was initiated to evaluate green color retention under three different soil systems. Several turfgrasses were evaluated in multi-layer, USGA, and mono-layer systems. Turfgrass entries were comprised of three cultivars of Korean lawngrass (Zoysia japonica Steud.) as warm-season grass (WSG) and three blends and three mixtures of Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), and tall fescue (TF, Festuca arundinacea Schreb.) as cool-season grass (CSG). Significant differences were observed in visual turf color and green color retention among soil systems and turfgrasses. Both the multi-layer and USGA systems were highly associated with better color ratings and longer color retention, as compared with the mono-layer system. Seasonal variation of visual turf color greatly occurred from late December to early spring. CSG exhibited longer color retention than did WSG. The latter maintained green color for approximately 6 months, regardless of the soil system. Spring green-up of Korean lawngrass occurred from early to middle May, while it underwent discoloration from late October to early November. Among the CSGs green-up occurred between early March and early April and leaf color was maintained until middle December to early February. Therefore, the CSGs were green for 8.5 to 11 months, depending on turfgrass and soil system. The mean period of green color duration across all soil systems was approximately 10-11, 9-10 and 8.5-9.0 months for PR, KB and TF, respectively. As for the CSG mixtures, the greater the proportion of PR, the longer the green color retention, while the higher the proportion of TF, the shorter the color retention. There was greater variation in green color duration among the CSGs than the WSGs. Across soil systems, color retention differences of 2 to 6 days were observed for the Korean lawngrass, but 7 to 36 days for the CSGs. These results demonstrate that green color retention varied greatly according to soil systems and also among turfgrasses. Selections of turfgrass and soil system should be made using a concept-oriented approach, when establishing garden, park, soccer field, golf course and other sports field. Information obtained in this study can be used to select soil systems and turfgrasses based on the expected degree of leaf color retention.

• Information Systems Review
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• v.7 no.2
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• pp.229-255
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• 2005

The Korea Development Bank promoted a total outsourcing for IT operation in 1999 for the first time in the banking industry. The Korea Development Bank became the center of public attention because the most banks were unwilling to take an outsourcing with external sources for the reason of financial operation accidents, securities, and threats of strikes. After the introduction of the total IT outsourcing, the Korea Development Bank has continuously diagnosed the problems of the IT outsourcing and adopted various proper complements for the enhancement of the IT outsourcing. As the result of the enhancement, the IT outsourcing of the Korea Development Bank marched into the joint liability operation period after going through the outsourcing operation period and the co-operation period. The joint liability operation which is the most leading outsourcing system which is adopted by the Korea Development Bank for the first time in the banking industry. Through the joint liability operation, the Korea Development Bank could accept the most up-to-date IT, concentrate internal manpower on the core capability, and secure flexibility of manpower. Also, the bank changed the relationship between the bank and the external sources from the one-sided relationship between a producers and a consumer to the joint liability relationship on which both sides are responsible for the operation, and could integrate the internal capacity with the professional know-how of the external IT outsourcing company. In this paper, we testified the soundness and validity for the worries of banks about the total IT outsourcing with external sources. And, we arranged the advantages and outcomes of the total IT outsourcing with external sources compared to the IT outsourcing with internal sources. Moreover, we expect that we can improve the closed financial IT outsourcing industry structure and raise the world competitive power of domestic IT outsourcing companies by correcting wrong ideas on the IT outsourcing with external sources.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.3
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• pp.217-224
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• 2016

Acinetobacter baumannii (A. baumannii) is prevalent in hospital environments and is an important opportunistic pathogen of nosocomial infection. It is known that this pathogen cause herd infection in hospitals, and the mortality rate is remarkably higher for patients infected with this pathogen and already have other underlying diseases. Herein, we investigated the antibiotic resistance rate and the type of resistance genes in 85 isolates of multi-drug resistant A. baumannii from the samples commissioned to laboratory medicine in two university hospitals-in hospital A and hospital B-located in Cheonan and Chungcheong provinces, respectively, in Korea. As a result, $bla_{OXA-23-like}$ and $bla_{OXA-51-like}$ were detected in 82 stains (96.5%). These 82 strains of $bla_{OXA-23-like}$ producing A. baumannii were confirmed with the ISAba1 gene found at the top of the $bla_{OXA-23-like}$ genes by PCR, inducing the resistance against carbapenemase. The armA, AME gene that induces the resistance against aminoglycoside was detected in 34 strains out of 38 strains from Hospital A (89.5%), and in 40 strains out of 47 strains from Hospital B (85.1%), while AMEs were found in 33 strains out of 38 strains from Hospital A (70.2%) and in 44 strains out of 47 strains in Hospital B (93.6%). Therefore, it was found that most multi-drug resistant A. baumannii from the Cheonan area expressed both acethyltransferase and adenyltransferase. This study investigated the multi-drug resistant A. baumannii isolated from Cheonan and Chungcheong provinces in Korea, and it is thought that the results of the study can be utilized as the basic information to cure multi-drug resistant A. baumannii infections and to prevent the spread of drug resistance.

• Journal of Food Hygiene and Safety
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• v.28 no.3
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• pp.258-266
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• 2013

This study was conducted to determine the PSL and TL properties of foods irradiated with electron beam and gamma-ray. 5 kinds of food including cereal, pulse, fish powder, dried vegetable and tea were irradiated at 0 to 10 kGy by electron beam accelerator or $^{60}Co$ gamma-ray irradiator. The PSL analysis showed negative results for most of the non-irradiated samples. Non-irradiated shrimp powder showed intermediate result. Irradiated samples gave negative or intermediate or positive value which presented the limitation of PSL technique. In TL analysis, there were TL glow curves at around $300^{\circ}C$ with low intensity on non-irradiated samples. Maximum peak in the range of $150-250^{\circ}C$ was appeared on irradiated samples. TL ratio obtained by re-irradiation with 1 kGy was less than 0.1 on non-irradiated samples and higher than 0.1 on irradiated samples. Therefore, in PSL measurement, electron-beam irradiated samples could obtain more clear results. TL analysis showed obvious difference between non-irradiated and irradiated samples. But the identification was impossible for the sample of rice and lemon tea. Because of it's low contents of mineral.

• Journal of fish pathology
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• v.10 no.2
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• pp.125-135
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• 1997

The possibility of identification of families of antibacterial agent residues in fish tissue was studied by disk assay using three test organisms, Bacillus subtilis BGA, Micrococcus luteus ATCC 9341, and Bacillus cereus var. mycoides ATCC 11778. In the present method, a simple clean-up procedure was performed to obtain the aqueous solution from homogenized flounder muscle sample(10g) in Mcilvaine buffer. Then, aqueous solution was fractionated into A and B to be used in disk assay by choloroform and Sep-Pak $C_{18}$ cartridge column after being defatted in hexane. The chloroform layer of fraction A was used for the analysis of macrolide antibiotics(ML), sulfa drugs(SA), chloramphenicol(CP), and quinolone antibiotics(QN). Adsorbed materials to Sep-Pak $C_{18}$ of fraction B were also employed for the analysis of penicillins(PC), tetracyclines(TC), and nitrofuran derivatives(NF) Minimun-detectable concentrations by the present method were, $0.1{\mu}g$/g for oxytetracycline, tetracycline, doxycycline, spiramycin and ciprofloxacin, $0.025{\mu}g$/g for erythromycin and ampicillin, $1.0{\mu}g$/g for sodium nifurstyrenate and florfenical, $0.25{\mu}g$/g for sulfamonomethoxie and sulfadimethoxine, $2.5{\mu}g$/g for oxolinic acid and flumequine, and $15{\mu}g$/g for piromidic acid, respectively. Three test organisms showed different sensitivity patterns for each family of antibacterial agent. Sensitivity patterns were B. cereus > B. subtilis > M. luteus for TC and NF, M. luteus > B, subtilis > B. cereus for ML and PC, B. cereus = B. subtilis > M. luteus for CP and QN, and B. subtilis > B. cereus＝M. luteus for SA. The present method utilizing these characteristics could be useful as a routine screening test for the determination of family of antibacterial agent residues in fish tissue.

• Journal of Gifted/Talented Education
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• v.25 no.2
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• pp.339-358
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• 2015

This study was to examine perceptions of information technology(IT) competencies among gifted and non-gifted students(i.e., information science high school students and technical high school students). Of the 370 high school students surveyed from 3 high schools(i.e., gifted academy, information science high school, and technical high school) in three metropolitan cities, Korea, 351 students completed and returned the questionnaires yielding a total response rate of 94.86%. High school students recognized the IT professional competence as being most important when recruiting IT employees. And they considered that practice-oriented education was the most importantly needed to improve their IT skills. In addition, the most important sub-factors of IT core competencies among gifted academy students and information science high school students were basic software skills. Also Technical high school students responded that the main network and security capabilities were the most importantly needed to do so. Finally, the most appropriate training courses for enhancing IT competencies were recognized differently among gifted and non-gifted students. Gifted academy students responded that the 'algorithm' was the mostly needed for enhancing IT competencies, whereas information science high school students responded that 'data structures' and 'computer architecture' were mostly needed to do. For technical high school students, they responded that a 'programming language' course was the most needed to do so. Results are discussed in relations to IT corporate and school settings.