• The korean journal of orthodontics
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• v.36 no.6
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• pp.412-421
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• 2006

Objective: The result of finite element analysis depends on material properties, structural expression, density of element, and boundar or loading conditions. To represent proper elastic behavior, a finite element model was made using Hounsfield unit (HU) values in CT images. Methods: A 13 year 6 month old male was used as the subject. A 3 dimensional visualizing program, Mimics, was used to build a 3D object from the DICOM file which was acquired from the CT images. Model 1 was established by giving 24 material properties according to HU. Model 2 was constructed by the conventional method which provides 2 material properties. Protraction force of 500g was applied at a 45 degree downward angle from Frankfort horizontal (FH) plane. Results: Model 1 showed a more flexible response on the first premolar region which had more forward and downward movement of the maxillary anterior segment. Maxilla was bent on the sagittal plane and frontal plane. Model 2 revealed less movement in all directions. It moved downward on the anterior part and upward on the posterior part, which is clockwise rotation of the maxilla. Conclusion: These results signify that different outcomes of finite element analysis can occur according to the given material properties and it is recommended to use HU values for more accurate results.

• Journal of Radiation Protection and Research
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• v.40 no.1
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• pp.1-9
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• 2015

Compton cameras overcome several limitations of conventional mechanical collimation based gamma imaging devices, such as pin-hole imaging devices, due to its electronic collimation based on coincidence logic. Especially large-scale Compton camera has wide field of view and high imaging sensitivity. Those merits suggest that a large-scale Compton camera might be applicable to monitoring nuclear materials in large facilities without necessity of portability. To that end, our research group have made an effort to design a large-scale Compton camera for safeguard application. Energy resolution or position resolution of large-area detectors vary with configuration style of the detectors. Those performances directly affect the image quality of the large-scale Compton camera. In the present study, a series of Geant4 Monte Carlo simulations were performed in order to examine the effect of those detector parameters. Performance of the designed large-scale Compton camera was also estimated for various monitoring condition with realistic modeling. The conclusion of the present study indicates that the energy resolution of the component detector is the limiting factor of imaging resolution rather than the position resolution. Also, the designed large-scale Compton camera provides the 16.3 cm image resolution in full width at half maximum (angular resolution: $9.26^{\circ}$) for the depleted uranium source considered in this study located at the 1 m from the system when the component detectors have 10% energy resolution and 7 mm position resolution.

• Journal of The Korean Association For Science Education
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• v.36 no.3
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• pp.471-483
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• 2016

The purpose of this study is to explore how students' epistemological framing and positional framing affect the role of wonderment questions related to the activation of conceptual resources and to investigate what contexts affect students' framings during scientific model construction. Four students were selected as focus group and they participated in collaborative scientific model construction of mechanisms relating to urination. According to the results, one student whose framings were "understanding phenomena" and "facilitator" asked wonderment questions, but the others whose framings were "classroom game" and "non-respondent" were not able to activate their conceptual resources. However, they were able to activate their conceptual resources when they shared the epistemological framing of "understanding phenomena" and shifted between the positional framings of "facilitator" and "respondent." Although they were able to activate their conceptual resources, these activated resources were not able to contribute to their model when they shifted to the framings of "classroom game" and "receiver." In contrast, when students constantly shared an "understanding phenomena" framing and dynamically shifted between the framings of "facilitator" and "respondent," they were able to activate various conceptual resources and develop their group model. The students' framings were affected by the contexts. These included: when students were confronted with cognitive difficulties and were not provided proper scaffolding; when the teacher played the role of answer provider and guided the activity with correctness; when there were several possible explanatory models that students could choose from; and when the teacher played the role of thought facilitator. This study contributes to supporting teaching and learning environments for productive scientific model construction.

• Journal of The Korean Association For Science Education
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• v.33 no.2
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• pp.478-485
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• 2013

"GukMinSoHakDokBon", published in 1895, is the first national textbook designated by the Education Institute. Ten of the 41 chapters consist of scientific contents. In this thesis, some the contents are reviewed in detail and studied to see what significance it has in view of science education. The scientific contents described in "GukMinSoHakDokBon" include Plants Change, Clock, Camels, Wind, Hive, Respiration, Crocodiles, Nature of Animals, and Chemical Elements. For that kind of diversity, it was told that "GukMinSoHakDokBon" was not considered for normal students, and there were many ambiguities due to in sufficient explanations. Some of the contents were even technically wrong. So it has been noted that the scientific contents of "GukMinSoHakDokBon" have more significance in providing new information at that time but not in understanding newly-organized scientific knowledge. However, it is obvious that the early science education in Korea is composed of the methods of reading "GukMinSoHakDokBon". This is a common figure, which can be found in "Willson's Reader", the elementary reading textbook in the U.S. in the 1860's or "小學讀本" by the Ministry of Education in Japan. One thing remarkable is "GukMinSoHakDokBon" induced students' interests through the use of storytelling method for introducing some unfamiliar scientific knowledge. There is no doubt that "GukMinSoHakDokBon" has a very positive role in increasing students interest and intelligence. These advantages are being actively applied in the present model of storytelling education these days. Therefore, "GukMinSoHakDokBon" can be regarded as both a language textbook and an early figure in science education, and it can be also considered that "GukMinSoHakDokBon" has a significance not only in approaching scientific substances theoretically but in using storytelling methods to deliver unfamiliar and strange knowledges to students.

• Culinary science and hospitality research
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• v.18 no.5
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• pp.1-15
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• 2012

This study analyzed the influence of the quality of medicinal food on perceived values, repurchase intention and recommendation intention. The objective of this study is to suggest the efficient operating direction for specialized medicinal food restaurants to grow as an axis of the food service industry by showing the future direction of medicinal food and establishing marketing strategies to maintain/secure customers. From June 15th to July 2nd, 2009, the survey was conducted for the customers of medicinal food restaurants, located in Seoul and Gyeonggi-do. After distributing 250 copies of questionnaire, 195 of them were collected and total 192 were used for the analysis after excluding three copies due to lack of showing sincerity. The analysis results of this study can be summarized as follows. First, the quality of medicinal food was found to have a significant influence on 'functional value(t=5.519)' while having no influence on 'social value.' Second, the 'nutritional quality' of medicinal food was analyzed as having a significant influence on 'social value(t=10.954)' and 'functional value'(t=8.237).' Third, the 'medicinal quality' of medicinal food was analyzed as having no significant influence on 'social value(t=1.191)' and 'functional value(t=0.022).' Fourth, it was found that 'social value' had a significant influence on repurchase intention(t=9.743) and recommendation intention(t=9.154). Fifth, the functional value was analyzed as having a significant influence on repurchase intention(t=7.895) and recommendation intention(t=8.143). The results of the empirical analysis shown in this study properly support the theoretical standard system to achieve successful performance and useful information necessary for systematic operation of specialized medicinal food restaurants.

• Tuberculosis and Respiratory Diseases
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• v.41 no.3
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• pp.248-261
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• 1994

Background: Lectins are proteins or glycoproteins of non-immune origin that recognize a specific sequence of sugar residues. The availability of a large number of lectins has provided the capacity to identify selectively glycoconjugates possessing distinctive chemical structure in diverse sites of highly specialized biological activity. The purpose of the present study was to investigate the lectin binding patterns of various components in human pulmonary tubercles. Method: Biopsy specimens of tuberculous lung were obtained from male adult patients who underwent a surgical resection for severe pulmonary tuberculosis. The specimens were processed and stained with 13 kinds of biotinylated lectins according to some modification of Hsu and Raine's methods. Results: 1) In the caseous necrotic lesions, BS $I-B_4$ showed negative reaction and BS I were also negative except some irregularly-shaped cells located in the marginal zone. All other lectins, however, showed a positive reaction with various binding patterns. 2) The epithelioid cells were broadly divided into three groups according to the reaction patterns in the cytoplasms and cell membranes. 3) WGA, ECL, PHA-L, PHA-E and LCA showed strong staining in the lymphocytes. 4) SBA showed a different binding patterns between the endothelial layers located in the region beyond the fibrous layers and those located within the fibrous layers. 5) PNA showed a positive reaction in the outer 1/3 to 1/2 of the fibrous layer, but showed no staining in the inner 1/2 to 2/3 of the fibrous layers. Conclusion: The present lectin histochemical study provided a useful information to assess the characterization and distribution of various glycoconjugates in each constituent of human pulmonary tubercles. The results demonstrate structural differences in the glycoconjugate composition of various components of the tubercles and reveal changes in glycosylation in the components during soft tubercle formation. This study provides a new data useful for the studies on the pathogenesis and pathology of human pulmonary tubercles.

• Tuberculosis and Respiratory Diseases
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• v.43 no.3
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• pp.388-402
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• 1996

Background : To compare the diagnostic accuracies of High-resolution CT(HRCI) and chest radiography in the diagnosis of diffuse infiltrative lung disease(DILD). Methods : This study included ninety-nine patients with a diagnosis of acute or chronic DILD, representing 20 different diseases. Twelve normal subjects were included as control. The disease state was confirmed either pathologically or clinically. Radiographs and CT scans were evaluated separately by three independent observers without knowledge of clinical and pathologic results. The observers listed three most likely diagnoses and recorded degree of confidence. Results : The sensitivity of HRCT in the detection of DILD was 98.9% compared to 97.9% of chest radiography. Overall, a correct first-choice diagnosis was made in 48% using chest radiographs and in 60% using HRCT images. The correct diagnosis was among the top-three choices in 64% when chest radiographs were used, and in 75% when HRCT images were reviewed. Overally a confident diagnosis was reached more often with HRCT(55%) than with chest radiography(26%). The correct first-choice diagnosis increased remarkably when the HRCT was used in usual interstitial pneumonia, miliary tuberculosis, diffuse panbronchiolitis and lymphangitic carcinomatosis. Conclusion : HRCT is confirmed to be superior to conventional radiography in the detection and accurate diagnosis of DILD. HRCT is especially valuable in the diagnosis of usual interstitial pneumonia, miliary tuberculosis, diffuse panbronchiolitis, and lymphangitic carcinomatosis.

• Tuberculosis and Respiratory Diseases
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• v.55 no.4
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• pp.344-352
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• 2003

Background : The prevalence of multidrug resistant tuberculosis (MDR-TB), resistant to isoniazid (INH) and rifampin (RFP), was 5.3% worldwide in 1995 and its increment has raised important public health problems. Resistance to RFP, one of the key drugs in the treatment of tuberculosis, results in grim clinical outcome. Recently rapid detection of RFP-resistant mutations in rpoB gene based on PCR method has become available. This study evaluated the prevalence of RFP resistance in first diagnosed, treatment failure, and recurred patients using INNO-LiPA test, and compared the results of INNO-LiPA with those of conventional mycobacterial drug susceptibility test. Methods : Forty-six patients, who were diagnosed of pulmonary tuberculosis and had revealed positive sputum AFB smear, were enrolled in this study from 1998 to 2002. The cases were classified as one three groups; first diagnosed, treatment failure, or recurred. RFP resistance was studied using an INNO-LiPA Rif. TB kit and compared with that obtained from drug susceptibility based on M. tuberculosis culture study. Results : Twenty-one out of 46 patients were enrolled under first diagnosis of pulmonary tuberculosis, 17 under treatment failure with first line drugs, and 8 under recurrence. The positive and negative predictive values of INNO-LiPA test in diagnosis in RFP resistant tuberculosis compared with conventional mycobacterial drug susceptibility test were 85.7% and 76.0%, respectively. INNO-LiPA result revealed rpoB gene mutation in 20 (80.0%) out of 25 patients who were diagnosed as treatment failure or recurrence, but in only 4 (19.0%) out of 21 patients who were first diagnosed as pulmonary tuberculosis. Conclusion : This study showed that RFP resistance could be diagnosed rapidly and accurately using INNO-LiPA test and that this test might be helpful for choosing second line anti-mycobacterial drugs. It might be of great help in clinical diagnosis and decision when used in complimentarily with drug susceptibility test based on M. tuberculosis culture.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.441-445
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• 2005

Researches on estimating national-scaled forest biomass are being carried out to quantify the carbon stock of forests with the Kyoto Protocol. In general, estimates of national-scaled forest biomass are based on forest inventory data which provides estimates of forest area, stem volume, and growth of stem by age classes. Estimates of forest biomass are, however, obtained by converting stem volumes to dry weight with stem density and thereafter to whole tree biomass with biomass expansion factors (ratios of whole tree dry weight to stem dry weight). Pinus densiflora is widely distributed and one of the most economically important timber species in Korea. The species are largely grouped into two ecotypes of Geumgang and Jungbu. Stems of Geumgang type trees are straight and high compared to those of Jungbu type trees. The objective of this study was to determine and compare stem density and biomass expansion factors fore two ecotypes of Pinus densiflora according to stand age. Stem density of both ecotypes of Pinus densora increased and biomass expansion factors of them decreased with increasing tree age. In he same age class, stem density and biomass expansion factor of Geungang type Pinus densiflora were lower than those of Jungbu type Pinus densiflora. There were statistically significant differences in stem density and biomass expansion factors between Geumgang type and Jungbu type Pinus densiflora in 0-20-year-old stands and 40-60-year-old stands. Our results suggested that the reliability of the national forest biomass inventory could be improved by applying the ecotype- and age-dependent stem density and biomass expansion factors.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.174-179
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• 2000

The nitrogenous compounds in the muscle extracts of cultured and wild olive flounder, Paralichthys olivaceous, were analyzed. The analyzed coumpounds were extractive nitrogen, free amino acids, oligopeptides, ATP and its related ompounds, quaternary ammonium bases, and guanidino compounds. The distribution pattern of these compounds in cultured and wild fish was found to be very similar. Although the ATP and its related compounds and creatine in the muscle of cultured fish were slightly abundant than those in the muscle of wild one, the extractive nitrogen, total free amino acid, oligopeptides, and TMAO were found to be slightly rich in the muscle of wild fish than those in the muscle of cultrued one. The moisture content of cultured fish was relatively lower but the protein and fat contents of cultured one were higher than those of wild fish. However the differences in the proximate composition, extractive nitrogen and nitrogenous compounds between two fishes were not significantly different.