• Journal of The Korean Association For Science Education
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• v.38 no.3
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• pp.393-405
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• 2018

In this study, we classified the group model construction types in the actual classroom situation implementing the instructional strategy mixed with individual model construction and group model construction types. The purpose of this study is to analyze the information flow and the individual construction types of each group model construction type to obtain implications for model co-construction in a real classroom environment. A two-session class on sound propagation was carried out for thirty-three 8th grade students in Seoul. A total of 65 individual model construction and 16 group model construction processes were collected and analyzed. The group model construction types were classified as unchanged, enumerated, and elaborated. The unchanged type was found in 8 groups, the enumerated type in 3 groups, and the elaborated type in 5 groups. The isolated individual and independent construction (i.I) were found mostly in the unchanged group construction type (50.0%) and enumerated group construction type (54.5%). In the unchanged type, the radial shape of flow in which one student's information is transmitted to all the members of the group appeared. In the enumerated type, the starting point of the information flow was observed from two individuals. In the elaborated type, linear information flow appeared and both the second dissemination and reflective construction (2d.R) contributed to the group model construction (58.3%). This study suggests a viewpoint that enables to understand the process of complex model construction in an actual classroom context rather than in an ideal situation. The result of this study suggests the necessity of a modeling strategy considering the characteristics of Korean small group culture. It is expected that the discussion will progress through further studies.

• Tuberculosis and Respiratory Diseases
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• v.57 no.5
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• pp.405-410
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• 2004

Background : Moxifloxacin is an 8-methoxyquinolone compound which has been shown to have the best activity of the quinolones against M. tuberculosis but there is no literature showing the rate of cross-resistance between moxifloxacin and the other quinolones such as ofloxacin. Therefore, we tested the activity of moxifloxacin against ofloxacin resistant M. tuberculosis by a study of cross-resistance. Methods : We tested MIC's of moxifloxacin and ofloxacin by proportion method against 34 M. tuberculosis isolates showing resistance against ofloxacin at $2.5{\mu}g/m{\ell}$ concentration and 13 ofloxacin susceptible isolates from specimens submitted to clinical laboratory of National Masan Hospital from March 2003 to March 2004. Results : For ofloxacin susceptible isolates, $MIC_{50}$ and $MIC_{90}$ of ofloxacin were all $1.25{\mu}g/m{\ell}$, and $MIC_{50}$ and $MIC_{90}$ of moxifloxacin were $0.31{\mu}g/m{\ell}$ and $0.63{\mu}g/m{\ell}$ respectively. For ofloxacin resistant isolates, $MIC_{50}$ of ofloxacin was over $10{\mu}g/m{\ell}$ and $MIC_{50}$ of moxifloxacin was $5{\mu}g/m{\ell}$, $MIC_{90}$ of ofloxacin and moxifloxacin were all over $10{\mu}g/m{\ell}$. The rate of cross-resistance between the two was 67.6%(23/34) at $2.5{\mu}g/m{\ell}$ concentration. Conclusions : Moxifloxacin showed activity against 82.4%(28/34) of ofloxacin resistant M. tuberculosis at $10{\mu}g/m{\ell}$, but more studies are needed so that moxifloxacin will be used for patient with multi-drug resistant tuberculosis including oflokacin resistance.

• Research in Community and Public Health Nursing
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• v.12 no.2
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• pp.397-405
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• 2001

The vision disturbances of school- age children has been recognized as and important school health problem. As the visual disturbances of the school-age children is recognized as the nation's health problem. the importance of the development of educational program for visual health should be emphasized. Recently, eyeball movement and other visual health management method has been introduced for prevention or recovery of decrease in visual acuity. But, the effect of eyeball movement was not confirmed yet. And, the controversy around the treatment effect is continued. The decrease of visual acuity is one of the important school health problem as well as it causes discomfort in daily life of the students. So, it should be considered as an important subject for school health and there is a need to develop an effective intervention program for visual health. The purpose of this study is to develop and evaluate the program with the recognition of the need of the intervention for visual health. The visual health promotion program was developed by the researcher and the program was initiated by the school. Nonequivalent control group pretest-posttest design was applied for study which examined the effect of the visual health promotion program. The subjects were 742 children (experimental group: 398; control group: 344). The experiment was composed of health education and eyeball movement. Health education was provided 5 times to the children in the class room. Children of experimental group exercised eyeball movement in the class, watching video for 10 minutes two times a day. The exercise was continued for 10 weeks. The result of the study were as follows. 1) change of visual acuity Before the intervention, mean of the visual acuity was .86 for the experimental group and .91 for control group. After the intervention, mean of visual acuity was .95 for the experimental group and. 90 for the control group. There was no significant difference in the change of visual acuity between experimental and control group. 2) change of refraction. In the experimental group, 327 eyes (41.08%) were normal vision and 469 eyes (58.98%) were eyes of refraction errors, 38.82 % of the total eyes were myopia. There was no significant change in the refraction in the children with myopia after the intervention. 3) Awareness of visual acuity, change of knowledge, behavior. and attitude (1) After the intervention, there was a significant difference in the awareness of visual acuity (experimental group: 70.10%. control group: 50.97%, p<.01). (2) After the intervention, there was a significant knowledge increase in the experimental group (pp<.01). (3) There was no significant difference in the visual health behavior after the intervention. (4) There was a significant positive change in the attitude related to visual health in the experimental group ( pp<.05). 4) There was a significant positive change in the subjective discomfort of the students. But, there was no significant change in the objective eye symptom after the intervention. Even though there was no effect in the visual acuity and the change of the refraction. subjective visual health as well as the attitude and knowledge' of the children and parents toward visual health was improved significantly. Also, there was an increase in the intention of change and the awareness for the visual health management. It is suggested that various educational strategies for visual health promotion should be developed and examined for the visual health promotion of the students.

• 한국벤처창업학회:학술대회논문집
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• 2007.04a
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• pp.405-433
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• 2007

This study is conducted to examine how purchase behaviors of consumers have affected by the promotion of coupons in internet shopping mall. This study was conducted with the purpose of identifying the differences in purchase behavior based on consumer' s perception and experience of internet shopping mall coupons, and based on consumers' perception of cost and value of coupons, using a theoretic framework presented in previously conducted studies. The results of this study can be summarized as follows. First, based on the perception of coupons, there were significant differences in intent to use and intent to re-use at the time when coupons are offered, and at the time when coupons are offered, no significant differences were found between the level of interest and the importance of coupon at the time of visiting the shopping mall; however, significant differences were found in the overall purchase behavior based on perception of coupons. Second, when overall differences m purchase behavior based on experience in coupon use was observed, having experience in using coupons showed a higher average than did having no experience in using coupons, showing a significant difference. It was found that compared to those without experience in using coupons, those with experience with coupons had higher intent to use at the time when coupon is offered, intent to re-use at the time when coupon is offered, and higher level of purchase behavior in the importance of coupons at the time of visiting the shopping mall. Third, when relationship between purchase behaviors, cost of coupon, and perception of convenience was observed, a clear static relationship was found. This suggests that as the cost and perception of convenience of coupon increases, purchase behavior also increases. Such result suggests that there is a difference in purchase behavior based on experience in coupon use. When relationship of purchase behavior by variables of cost of coupon and perception of convenience is observed, it has a positive relationship with the perception that the use of coupon includes saving money, financial help, enjoyment of use, habitual use, has a short effective date, and has a negative relationship with the perception that it saves little money and is a waste of time. Therefore, it can be seen that purchase behavior has the highest relationship with enjoyment of coupon use and habitual coupon use. Such results suggest that purchase behavior will be significantly influenced based on cost of coupon and perception of convenience.

• Tuberculosis and Respiratory Diseases
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• v.63 no.5
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• pp.405-411
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• 2007

Background: The objective of this study was to evaluate the clinical applicability of the repeatability criteria recommended by the American Thoracic Society/European Respiratory Society (ATS/ERS) spirometry guidelines and to determine which factors affect the repeatability of spirometry in Korean adults. Methods: We reviewed the spirometry data of 4,663 Korean adults from the Korean National Health and Nutritional Examination Survey (KNHANES) Chronic Obstructive Pulmonary Disease Cohort (COPD cohort) and the Community-based Cohort Study VI-Fishing village/Islands (community cohort). We measured the anthropometric factors and differences between the highest and second-highest FVC (dFVC) and $FEV_1$ ($dFEV_1$) from prebronchodilator spirometry. Analyses included the distribution of dFVC and $dFEV_1$, comparison of the values meeting the 1994 ATS repeatability criteria with the values meeting the 2005 ATS/ERS repeatability criteria, and the performance of linear regression for evaluating the influence of subject characteristics and the change of criteria on the spiro-metric variability. Results: About 95% of subjects were able to reproduce FVC and $FEV_1$ within 150 ml. The KNHANES based on the 1994 ATS guidelines showed poorer repeatability than the COPD cohort and community cohort based on the 2005 ATS/ERS guidelines. Demographic and anthropometric factors had little effect on repeatability, explaining only 0.5 to 3%. Conclusion: We conclude that the new spirometry repeatability criteria recommended by the 2005 ATS/ERS guidelines is also applicable to Korean adults. The repeatability of spirometry depends little on individual characteristics when an experienced technician performs testing. Therefore, we suggest that sustained efforts for public awareness of new repeatability criteria, quality control of spirograms, and education of personnel are needed for reliable spirometric results.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.399-405
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• 2011

In this study, we evaluated the fruit quality indices and the incidence of physiological disorders of Korean new pear cultivar 'Whasan' to determine appropriate harvest time for exportation and to enhance storability and shelf-life of the fruits during simulated exportation and extending market environment under different temperature conditions. In the experiment of simulated exportation headed for North America including Canada and U.S.A., the fruits transported at $1^{\circ}C$ showed less weight loss than those of $5^{\circ}C$. Market temperature appeared as a key factor for keeping freshness of exported pear fruits rather than transportation temperature. Quality factors such as high flesh firmness and low incidence of fruit rot and physiological disorders including core breakdown and pithiness were attained at the fruits maintained at $18^{\circ}C$ when we compared with $25^{\circ}C$. The fruits of harvested early maturity at 135 day after full bloom showed 28.6 N of flesh firmness when the fruits stored at $1^{\circ}C$ of transportation and $18^{\circ}C$ of market temperature, while the fruits progressed $5^{\circ}C$ of transportation and $25^{\circ}C$ of market temperature dropped to 24.2 N during 30 days of shelf life. Also, a high incidences of physiological disorders and of fruit decay rates were obvious in the fruits distributed at $25^{\circ}C$ were observed approximately two times higher than the those of $18^{\circ}C$. Therefore, temperature management during marketing resulted as an important point for maintaining fruits quality in the process of pear fruit exportation.

• Korean journal of food and cookery science
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• v.28 no.4
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• pp.399-405
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• 2012

This study was carried out to investigate the effect of safflower seed powder on the physicochemical characteristics of ground pork during refrigerated storage. Three types of ground pork were evaluated: 20% pork fat added (PF, control), 10% pork fat and 10% added safflower seed powder (PFS), and 20% added safflower seed powder (SS). The pH increased during storage, but decreased after 10 days of the storage (p<0.05). The pH was lower in PFS and SS than that in PF after 10 days of storage (p<0.05). The TBARS (2-thiobarbituric acid reactive substances) values increased with longer storage period (p<0.05), and those of PF, PFS and SS were 1.186, 0.686 and 0.577 mg MA/kg, respectively, after 10 days of storage. The $L^*$ values for external color of PF and PFS decreased (p<0.05), but that of SS was not significantly different after a longer storage period. The $a^*$ values decreased (p<0.05), but the $b^*$ values were not significantly different with longer storage period. The $L^*$ values for internal color of PFS and SS decreased (p<0.05), but that of PF was not significantly different with longer storage period. The $a^*$ value of PF decreased (p<0.05), but that of SS increased with longer storage period. The $b^*$ value decreased (p<0.05), but those of PFS and SS were not significantly different with longer storage period. Water holding capacity decreased with longer storage period, and that of SS was the highest (p<0.05). Cooking loss of PFS and SS was not significantly different with longer storage period, and that of PF was the highest (p<0.05). The reduction in diameter of the samples was not significantly different with longer storage period, and that of PF was the highest (p<0.05). Hardness and chewiness of samples increased, but springiness and cohesiveness decreased with longer storage period (p<0.05). Replacing animal fat with safflower seed powder was effective and may be useful as an innovative meat product.

• Korean journal of food and cookery science
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• v.25 no.4
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• pp.395-405
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• 2009

In this study, a survey was conducted to determine consumer perceptions and satisfaction for onion hot-water extracts. Among the study subjects, females (53.3%) were in greater number than males, and individuals in their 40s (35.1%) made up the largest group. Cocerning the detailed efficacy of onion hot-water extracts, most respondents (84.5%) were aware of their efficacy and females recognized this more than males (p<0.001). Most consumers (67.3%) purchased onion hot-water extracts from 'health food stores prepared using a double boiler', and many consumers (47.4%) received information on the extracts from families and relatives. Of the respondents, 51.8% said they purchased 'quantities for $1{\sim}3$ months' at one time, and 33.1% stated that the price of onion hot-water extracts was expensive. They considered 'health' the most important aspect when purchasing, and preferred 'pouch packs' (60.3%) and considered 'easiness to open convenience to drink, and safety' (42.0%) the most important product features. Also, 62.8% of the respondents consumed onion hot-water extracts, and many drank them $1{\sim}3$ times a week, with '70 mL' as one dose, and drank them 'regardless of time'. The consumers were satisfied with the listing of health effects, but were not satisfied with the 'taste', 'smell', or 'color' of products. Concerning advertisements for the efficacy of onion hot-water extracts, 72.5% replied 'I trust them a little'. And concerning the expanding onion hot-water extract market, many respondents said it is difficult to choose an onion hot-water extract due to many similar products at the market. They also requested improvements of taste and flavor.

• Korean Journal of Poultry Science
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• v.49 no.2
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• pp.53-60
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• 2022

This study investigated correlations between egg quality indicators to identify external egg quality traits to predict internal egg quality using non-destructive and convenient measurements. Thirteen indicators, including Haugh unit, albumen height, eggshell breaking strength, eggshell thickness, eggshell color (CIE L^*, CIE a^*, CIE b^*), and reflectivity value, egg weight, egg length, egg width, shape index, and yolk color, were investigated. A total of 180 brown eggs were obtained from one 27-week-old flock of Hy-line brown-laying hens raised in a cage system. Correlations were evaluated using Pearson's correlation coefficient (r). The results showed strong correlations between Haugh unit and albumen height, eggshell color CIE L^* and reflectivity, egg weight and width, egg weight and length, eggshell color CIE L^* and CIE a^*, eggshell color CIE a^* and reflectivity, and shape index and egg length (P<0.001). Moderate correlations were observed between eggshell breaking strength and eggshell thickness, eggshell color CIE a^* and CIE b^*, and shape index and egg width (P<0.001). Eggshell color CIE L^* was correlated with eggshell breaking strength (P<0.01), and eggshell color CIE a^* was correlated with Haugh unit, albumen height (P<0.01), and eggshell breaking strength (P<0.001). The present study showed significant correlations between eggshell color and other quality indicators. Thus, this study suggests that eggshell colors based on reflectiveness and the CIE L^*a^*b^* value can be used to estimate the Haugh unit, albumen height, eggshell breaking strength, and thickness.

• Korean Journal of Mineralogy and Petrology
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• v.37 no.1
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• pp.1-11
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• 2024

World stone production in 2021 stood at 162.5 million tons, up by 7.5 million tons, or 4.8 percent, compared to the previous year when the production came in at 155 million tons. Six top countries with the most of stone production were China, India, Turkey, Brazil, Iran and Italy and these six countries accounted for 72.8 percent of total production in the world. Stone exports stood at $21.68 billion in 2021, up by $2.3 billion from the previous year. Exports of raw materials and processed stones stood at 54.4 million tons, up by 2.98 million tons from the previous year. In terms of aggregate exports, exports of natural stones increased by $2.3 billion to $21.7 billion while exports of artificial stones rose $2.6 billion to $13.6 billion in 2021 compared to the previous year. The average price of stone (Code: 68.02) was up by $65.2 per ton to $794.82. The price of board, processed stone, an ingredient for building materials, increased by $3.52 per square meter to $42.96 per square meter. Recycling was always the problem as the volume of the total quarry was 333.5 million tons, of which only 28.8 percent were finished products and the remaining 71.2 percent were waste generated from stone extraction and processing. Korea's stone exports stood at $1.97 million in 2021, down 38.3 percent on year, while imports were up 8.6 percent to $758.9 million. Stone exports are expected to grow to 66.1 million tons in 2025, while usage is expected to reach 108.92 million tons, or 2 billion square meters.