• Progress in Medical Physics
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• v.27 no.2
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• pp.93-97
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• 2016

In this study, we evaluate the effect of respiration on the dose distribution in patient target volume (PTV) during intensity-modulated radiation therapy (IMRT) and research methods to reduce this impact. The dose distributions, homogeneity index (HI), coverage index (CVI), and conformity index of the PTV, which is calculated from the dose-volume histogram (DVH), are compared between the maximum intensity projection (MIP) image-based plan and other images at respiration phases of 30%, 60% and 90%. In addition, the reducing effect of complication caused by patient respiration is estimated in the case of a bolus and the expended PTV on the skin. The HI is increased by approximately twice, and the CVI is relatively decreased without the bolus at other respiration phases. With the bolus and expended PTV, the change in the dose distribution of the PTV is relatively small with patient respiration. Therefore, the usage of the bolus and expended PTV can be considered as one of the methods to improve the accuracy of IMRT in the treatment of breast cancer patients with respiratory motion.

• Journal of radiological science and technology
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• v.40 no.1
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• pp.57-62
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• 2017

The purpose of this study is to reconstruct the treatment plan by applying CBCT and DIR to dose changes according to the change of the patient's motion and breast shape in the large breast cancer patients and to compare the doses using TWF, FIF and IMRT. CT and CBCT were performed with MIM6 to create DIRCT and each treatment plan was made. The patient underwent computed tomography simulation in both prone and supine position. The homogeneity index (HI), conformity index (CI), coverage index (CVI) to the left breast as planning target volume (PTV) were determined and the doses to the lung, heart, and right breast as organ at risk (OAR) were compared by using dose-volume histogram and the unique property of each organ. The value of HI of the PTV breast increased in all treatment planning methods using DIRCT, and CVI and CI were decreased in the treatment planning methods using DIRCT.

• Journal of the Korean Ceramic Society
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• v.41 no.7
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• pp.518-527
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• 2004

In this study, SiC whiskers were grown in porous alumina substrate in order to enhance the filtering efficiency, performance, and durability by controlling pore morphology. This experiment was performed by Chemical Vapor Infiltration (CVI) in order to obtain the whiskers on the inside of pores as well as on the surface of porous the A1$_2$O$_3$ substrate. The deposition behavior was changed remarkably with the deposition position, temperature, and input gas ratio. First, the mean diameter of whisker was decreased as the position of observation moved into the inside of substrate due to the reactant gas depletion effect'. Second, the deposition temperature caused the changes of the deposition type such as debris, whiskers and films and the change in morphology affect the various properties. When SiC films were deposited. the gas permeability and the specific surface area decreased. However, the whisker showed the opposite result. The whiskers increase not only the specific surface area and minimizing pressure drop but also mechanical strength. Therefore it is expected that the porous alumina body which deposited the SiC whisker is the promising material for the filter trapping the particles.

• Journal of The Korean Association For Science Education
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• v.39 no.2
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• pp.249-261
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• 2019

The purpose of this study is to extract empathy factor in scientists' problem-solving process and to examine how the empathy factor influences scientists' problem-solving situation. In this study, we selected six common persons among the scientists mentioned by creativity researchers. And through their autobiographies and biographies, we extracted elements of empathy from their case of problem-solving and categorized them. We analyzed cases from 12 books and 50 papers using Davis' empathy scale as an analysis framework and extracted common factors. As a result, the scientific empathy elements were extracted from a total of 182 cases, and 33 common elements were found. The validity of this case was verified through the content validity test of the science education specialist group. As a result, the I-CVI average was .86 and the S-CVI average was .90. For the empathy elements that scientists used in problem-solving cases, in cognitive empathy, three elements (empathy through other disciplines, empathy from the perspective of the research object, accommodating others' opinions) were extracted in terms of perspective-taking, and three elements (imagination thought experiment based on observation, thought experiment, feeling like part of object) in fantasy. And in affective empathy, three elements (influenced by fellow researchers' motivation, touching from the subject, excitement studying more) were extracted in terms of empathic concern and two elements (heartache for others' failure in their research, sensitivity to problems) in personal depression. This could not be said to be a perfect match for Davis' empathy, but it would be possible to define the scientific empathy elements based on these common elements found in the scientists' cases.

• The Journal of Korean Academy of Sensory Integration
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• v.17 no.2
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• pp.41-55
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• 2019

Objective : This study was conducted to validate the content validity of the Korean version of the school setting interview (SSI) that assesses the adequacy of school environments for students aged 9-19. Methods : The Korean version of the SSI, which was completed via a translation-reverse translation process, was verified by conducting a questionnaire on category suitability two times with 35 experts. Results : The content validity index (CVI) for the entire K-SSI tool was .90 in the first test. The "Maps and diagrams" measurement in reading items and the "Taking a shower" measurement in sports activities were both below .75. A second round of verification was conducted after the CVI was modified. As a result, the secondary verification CVI results were further raised to .93. Conclusion : This study confirmed that the K-SSI contains items that are appropriate to Korean culture; it has been proven to have high content validity. Future continuous research and clinical use are required to study the validity and reliability of the K-SSI. Further, this tool should also be applied to students with diverse disabilities who face difficulties in school settings.

• Korean Journal of Community Nutrition
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• v.27 no.2
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• pp.146-157
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• 2022

Objectives: This study aimed to develop and assess the content validity and internal consistency of a questionnaire on the feasibility of mobile dietary self-monitoring applications. Methods: We developed a feasibility questionnaire to assess the overall usage, convenience, usefulness, and satisfaction of mobile dietary applications. The initial draft of the questionnaire contained 17 items with yes/no, multiple-choice, and open-ended questions and 52 items on 5-point Likert scales. To validate the content, ten experts evaluated the relevance of the items for each subscale using a 5-point scale. We calculated the item-level content validity index (I-CVI) and scale-level content validity index (S-CVI). A total of 102 adults answered the questionnaires which reflected the experts' reviews. We conducted an exploratory factor analysis to determine the underlying structure of responses and categorized convenience, usefulness, and satisfaction. We also calculated Cronbach's alpha coefficient to examine the internal consistency of items in each subscale. Results: The S-CVI score of the items was 0.86, and we removed items with an I-CVI score of < 0.80. We combined, revised, or separated some remaining items and added one item as per the experts' comments. As a result, we included 16 items about overall usage and 42 sub-questions. Based on the responses of the 102 adults, we performed exploratory factor analysis using the principal axis method. We retained items with a factor loading of > 0.40, resulting in a final set of 35 questions (convenience: 15, usefulness: 12, satisfaction: 8 items). The Cronbach's alpha values of the three scales were 0.93, 0.91, and 0.91 for 1) usefulness, 2) convenience, and 3) satisfaction, respectively. Conclusions: We developed a feasibility questionnaire for mobile dietary self-monitoring applications and examined its content validity and internal consistency. Our questionnaire has the potential to measure the feasibility of mobile dietary self-monitoring applications.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.513-514
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• 2005

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.156.2-156
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• 2003

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.226.2-226
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• 2003

• Proceedings of the Materials Research Society of Korea Conference
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• 1993.05a
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• pp.138-138
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• 1993