• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.40 no.6
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• pp.313-315
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• 2014

An oral foregut cyst is a rare congenital choristoma lined by the respiratory and/or gastrointestinal epithelium. The exact etiology has not been fully identified, but it is thought to arise from misplaced primitive foregut. This lesion develops asymptomatically but sometimes causes difficulty in swallowing and pronunciation depending on its size. Thus, the first choice of treatment is surgical excision. Surgeons associated with head and neck pathology should include the oral foregut cyst in the differential diagnosis for ranula, dermoid cyst, thyroglossal duct cyst and lymphangioma in cases of pediatric head and neck lesions.

• The Korean Journal of Applied Statistics
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• v.25 no.6
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• pp.947-958
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• 2012

When modeling event times in biomedical studies, the outcome might be incompletely observed. In this paper, we assume that the outcome is recorded as current status failure time data. Despite well-developed literature the routine practical use of many current status data modeling methods remains infrequent due to the lack of specialized statistical software, the difficulty to assess model goodness-of-fit, as well as the possible loss of information caused by covariate grouping or discretization. We propose a model based on pseudo-observations that is convenient to implement and that allows for flexibility in the choice of the outcome. Parameter estimates are obtained based on generalized estimating equations. Examples from studies in bile duct hyperplasia and breast cancer in conjunction with simulated data illustrate the practical advantages of this model.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.667-677
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• 2013

The introduction of a new transit facility affects mode share of travel alternatives. The multinomial logit model, which has been the most commonly used for estimating mode share, has difficulty in reflecting heterogeneity of travelers' choices, and it has a limitation on grasping their characteristics of mode choice. The limitation may lead to over- or under-estimation of the new transit facility and bring about significant social costs. This paper aims to find a methodology to overcome the problem of preference homogeneity. It also applies market segmentation structure of separating the whole population into direct and indirect beneficiary to consider their preference heterogeneity. A mode choice model is estimated on data from Jeju Province and statistically tested. The results show that mode transfer rate of direct beneficiaries that inhabit in downtown areas increases as the new transit facility provides more advanced services with higher costs. The results and the model suggested in this study can contribute to improving the accuracy of demand forecasting of new transit facilities by reflecting heterogeneity of mode-transfer patterns.

• Journal of The Korean Association For Science Education
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• v.30 no.4
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• pp.452-471
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• 2010

As the Korean College scholastic Ability Test (CSAT) has been implemented for 17 years since 1994, it is becoming more and more difficult to make new items that haven't been previously used to measure students' thinking ability. Therefore, it is necessary to keep conducting research on making new test items that can measure students' scholastic ability reliably. For this reason, multiple choice items on the Japanese university entrance exam, which is a Japanese National Center Test for University Admissions (NCTUA) equivalent of CSAT, were analyzed in order to draw implications for CSAT item development. In this study, we analyzed the Japanese NCTUA administered in January 2009 to investigate the structure of its science test. We also analyzed the NCTUA items by the domains of contents and behaviors, and tried to predict item difficulty from the perspective of Korean applicants. Major findings are as follows: Most NCTUA items measure understanding knowledge or low level thinking ability. Also the alloted time for each item is longer than CSAT. The number of test items, and the number of choice and alloted points for each item are diverse, unlike CSAT. The number of items using real-life materials are much more, but the items are not rigorous in sentence expression compared to CSAT. And the difference of difficulty level among science tests were larger with reference to CSAT. Also science score is required for most applicants regardless whether they are taking liberal arts or going onto the science track.

• Journal of Distribution Science
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• v.15 no.8
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• pp.65-73
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• 2017

Purpose - Although e-learning has this advantage, currently many organizations have failed to recognize the necessity for basic e-learning educational training. It follows that practitioners working in the above organizations face the difficulty of having to find educational training processes of boosting their capabilities by themselves, rather than being able to utilize the educational training processes offered by e-learning. So of their own accord, learners have considered the necessity of information relating to being able to choose between high quality educational training processes. The purpose of this study is to propose opening e-learning content information for enabling an efficient choice of learning processes related to e-learning. Research design, data, and methodology - To pinpoint the items of e-learning content information, the study was initiated according to the following process. First, information relating to e-learning content (offered on e-learning websites) was researched. Second, based on the items of information which emerged from the research, selection and validity verification took place with 5 e-learning specialists as the subjects. Third, the opinions of adult learners at K University were collated relating to the items of information which emerged from the research. Results - The e-learning content information was comprised of 16 items in order to improve the choosing process for learner's e-learning contents. The analysis results showed that when learners were choosing e-learning processes, the most highly considered item was 'mobile support' (4.35). Following this (in order) were 'tuition fees' (4.30), 'certificate issuing' (4.23), and 'awareness of educational institution' (4.18). The least considered items were 'recruiting learners' (3.01) and 'tutor support' (3.18). Conclusions - The 16 items of e-learning content information in this study, were deemed to be helpful to learners in providing them with a choice of desirable e-learning process when this process was offered to them. Following this, there is a need for service institutions offering e-learning processes to make public the information suggested by this study. Research into educational methods additionally points to a necessity for not only e-learning forms, but also offline educational methods and a combination of blended learning to be offered and run parallel to e-learning.

• Journal of The Korean Association For Science Education
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• v.17 no.1
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• pp.93-101
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• 1997

The purpose of this study is to develop a test of earth science inquiry abilities using structured items. To develop a more valid and reliable instrument factual data was used, and most of the previous studies regarding inquiry teaching method and inquiry evaluation were consulted. The model developed in this study is composed of 5 stages; recognizing problems and generating hypotheses, designing inquiry, pursuiting inquiry, interpreting data, and drawing conclusion. Also, in this study 10 science inquiry abilities; recognizing problems, generating hypotheses, controlling variables, designing experiments, performing experiments, transforming data, inferencing, predicting, conclusing, and generalizing were clearly defined. The test developed in the study, Test of Earth Science Inquiry Abilities, includes 25 multiple-choice (five-choice) items and requires testing time of 50 minutes. The content validity of items, objectivity of scoring keys and clarity of items were checked by 7 experienced specialists in science education and earth science. The developed test were investigated and revised through three field tests. According to the results of the third field trial, test reliability (Cronbach $\alpha$) was 0.62, difficulty index was 0.54 and index of discrimination was 0.35. Also, the developed Test of Earth Science Inquiry Abilities showed a correlation coefficient of 0.53 with TIPS. Therefore, the development of Test of Earth Science Inquiry Abilities using structured items satisfied the reliability and validity requirements for general assessment instruments for students' earth science inquiry abilities.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.489-494
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• 2015

Background: Once limited with face-to face courses, health education has now moved into the web environment after new developments in information technology This study was carried out in order to give training to the university academic and administrative female staff who have difficulty in attending health education planned for specific times and places. The web-supported training focuses on healthy diet, the importance of physical activity, damage of smoking and stress management. Materials and Methods: The study was carried out in Sakarya University between the years 2012-2013 as a descriptive and quasi experimental study. The sample consisted of 30 participants who agreed to take part in the survey, filled in the forms and completed the whole training. The data were collected via a "Personel Information Form", "Health Promotion Life-Style Profile (HPLSP)", and "Multiple Choice Questionnaire (MCQ). Results: There was a statistically significant difference between the total points from "Health Promotion Life-Style Profile" and the total points from the sub-scale after and before the training (t=3.63, p=0.001). When the points from the multiple choice questionnaire after and before training were compared, it was seen that the average points were higher after the training (t=8.57, p<0.001). Conclusions: It was found that web-supported health training has a positive effect on the healthy living behaviour of female staff working at a Turkish university and on their knowledge of health promotion.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.7.1-7.7
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• 2015

Background: Osteoradionecrosis is a delayed complication from radiation therapy which causes chronic pain, infection and constant deformity after necrosis. Most of the osteoradionecrosis occurs spontaneously or after the primary oncologic surgery, dental extraction or by trauma of prosthesis. The treatment of osteoradionecrosis relies on both conservative measures and surgical measures. The fibular osteocutaneous free flap has become more popular choice for reconstruction of maxillofacial defects as a treatment of osteoradionecrosis. Methods: We presented our experiences from 7 patients with osteoradionecrosis who have had reconstruction surgery with fibular osteocutaneous free flap at National Cancer Center during the recent 5 years. We performed segmental mandibular resection with fibular osteocutaneous free flap for all 7 patients of advanced osteoradionecrosis who were not controlled by conservative treatment such as wound irrigation, debridement, and antibiotics. Results: A wide range of techniques were available for the reconstruction of composite defects resulted from the treatment of advanced mandibular osteoradionecrosis. Significant improvement was noted in relieving pain and treating trismus after the surgery however difficulty in swallowing and xerostomia showed less improvement. Conclusions: We concluded that fibular osteocutaneous free flap can be performed safely in patients with osteoradionecrosis and yields positive outcomes with significantly increased success rate. The fibular osteocutaneous free flap was our preferred choice for the mandibular reconstruction due to its versatility and predictability.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.1 no.1
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• pp.52-57
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• 2002

A simulation tool for an optimal ATIS design and drivers' dynamic route choice behavior analysis is developed, which is applicable to urban networks. Due to the difficulty to make drivers feel the time pressure according to traffic conditions, current SP questionnaire survey type surveys have a limitation to capture correct driver reactions to real-time traffic Information provision. The simulator Is a web-based upgraded version, named WATiSim (Web-based ATIS Simulator), to quickly perform a wide population survey with a minimal cost using INTERNET Furthermore, the time pressure issue is lessened by its interface and simulation modules. After WATiSim mimicked a VMS based ATIS in a partial network of Seoul Metropolitan, reactions of drivers to various traffic conditions were surveyed through INTERNET and analyzed using a logit model. Drivers under the ATIS environment clearly understood the provided traffic information, and their reactions were closely related to traffic conditions, scheduled delay, trip purposes as well as toll charge if any.

• Journal of the Korea Convergence Society
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• v.11 no.10
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• pp.279-286
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• 2020

The purpose of this study is multicultural adolescents' family reconstruction and maladaptation. Six multicultural adolescents living in Seoul, Gyeonggido, Chungchungdo, Jeolado were selected for the in-depth interview. Data were collected from August to December, 2019. This research is Giorgi's phenomenological method. The results provided 10 themes on the essential structure of experience and 4 theme clusters. The final 10 themes were unintentional choice: immigration, unfamiliar family relationship forming, unacceptable dissatisfaction and anger, absence of belonging and promising, missing homeland, keeping close relationship with old friends, difficulty of learning, following Korea culture, identity crisis and wandering, difficulty in adaptation : addiction to games and misdemeanour. Therefore, it is suggested to announce importance of family meaning and adaptation in Korea society.