• International Commerce and Information Review
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• v.16 no.5
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• pp.409-433
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• 2014

In this paper, I estimate long-run elasticities of US real GDP and real exchange rate between Korean Won and US Dollar on export of Korean goods to US and analyze changes in their trend by using VECM and rolling regression with a fixed window. For the purposes I use the year data from 1990 to 2013 which are selected from UNCTAD, Korea Trade Association(KTA), and Bank of Korea(BOK). The results are that the long-run elasticities of US real GDP vary from 2.849 to 2.938 for the period from 1990 to 2013 depending on the models in VECM and all of them are significant statistically. The elasticities of real exchange rate between Korean WON and US Dollar vary from 0.962 to 0.967 for the same period depending on the models in VECM and all of them are significant statistically. In case of the results through the OLS and the rolling regression, the long-run elasticities of US. real GDP are 3.015 for Basic Model, 2.949 for the modified Model 1, and 2.125 for the modified Model 2 for the period from 1990 to 2013 depending on the models and all of them are significant statistically. The average of long-run elasticities of real US GDP before the global financial crisis of 2008 is greater than that after the global financial crisis of 2008. On the other hand, the long-run elasticities of real exchange rate between Korean WON and US $ are 0.347 for Basic Model, 0.566 for the modified Model 1, and -0.217 for the modified Model 2 for the same period and all of them are significant statistically except for the modified Model 2. The average of long-run elasticities of real exchange rate before the global financial crisis of 2008 is greater than that after the global financial crisis of 2008.

• Korean Journal of Radiology
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• v.22 no.5
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• pp.677-687
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• 2021

Microvascular ultrasound (US) techniques are advanced Doppler techniques that provide high sensitivity and spatial resolution for detailed visualization of low-flow vessels. Microvascular US imaging can be applied to breast lesion evaluation with or without US contrast agents. Microvascular US imaging without a contrast agent uses a sophisticated wall filtering system to selectively obtain low-flow Doppler signals from overlapped artifacts. Microvascular US imaging with second-generation contrast agents amplifies flow signals and makes them last longer, which facilitates hemodynamic evaluation of breast lesions. In this review article, we will introduce various microvascular US techniques, explain their clinical applications in breast cancer diagnosis and radiologic-histopathologic correlation, and provide a summary of a recent radiogenomic study using microvascular US.

• Journal of Families and Better Life
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• v.16 no.3
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• pp.155-168
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• 1998

This study analyzed consumption structures of Korean households of 1991, 1993 and 1995 and compared them to those of Japan and US for setting consumption standards. The study also investigated if consumption structures of Korean and Japanese households are different according to their incomes and age of heads. It was found that the shares of the expenditures for food away home personal transportaton and education to total expenditures had been dramatically increased. It was also found that those shares were greater than those o Japanese and US households especially for younger households and households with highest income level.

• Journal of the Korean Home Economics Association
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• v.24 no.2
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• pp.25-35
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• 1986

The purpose of the study is to research unisex clothing attitude and clothing behavior and to compare the former with the later according to the different sex, the other walks of life and their professional occupations. The factors that one sex clothing has changed to the other sex clothing are illustrated in its attitude and then there are five distinguished parts such as aesthetics, utility, status symbol, conformity and modesty. A common questionaire is introduced for the way to survey them and the sources to measure them are gathered from the former studies for them but some of them are corrected, collegians in the city of Seoul, Sum total ; 578 students including 291 male students and 287 female students are investigated for this research. The date is analyzed by correlation, percentage, mean, analysis of variance and t-test. RESULTS : 1. The affirmative response to the questionaire is reflected stronger by the part of female's cloths changing to male's clothing than by the part of male's cloths changing to female's clothing. 2. Unisex clothing is more affirmative in the group of the same sex persons' living than in the group of the different sex people. 3. A unisex clothing goes for the characteristics of a person but it goes against the modesty. 4. The opinions from the negative group about Unisex clothing show us conspicuous viewpoints compared with them from the affirmative group about it. 5. The number of the group to describe the agreed opinion about Unisex clothing and to point out the trait of any person are so many. 6. While the number of the male group to be right view about Unisex clothing in becoming more and more female style shows us high interesting in status symbol for persons, the female group to agree with female Unisex clothing show us their high concerns at the utility.

• Journal for History of Mathematics
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• v.32 no.3
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• pp.97-108
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• 2019

This paper is an outgrowth of a study on recent papers and presentations of Hong Sung Sa, Hong Young Hee and/or Lee Seung On on Gugo Wonlyu which is believed to be written by the famous Joseon scholar Jeong Yag-yong. Most of what is discussed here is already explained in these papers and presentations but due to brevity of the papers it is not understood by most of us. Here we present them in more explicit and mathematical ways which, we hope, will make them more accessible to those who have little background in history of classical Joseon mathematics. We also explain them using elementary projective geometry which allow us to visualize Pythagorean polynomials geometrically.

• Korean Journal of Radiology
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• v.24 no.12
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• pp.1284-1292
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• 2023

Objective: We investigated the impacts of computed tomography (CT) added to ultrasound (US) for preoperative evaluation of patients with papillary thyroid carcinoma (PTC) on staging, surgical extent, and postsurgical survival. Materials and Methods: Consecutive patients who underwent surgery for PTC between January 2015 and December 2015 were retrospectively identified. Of them, 584 had undergone preoperative additional thyroid CT imaging (CT + US group), and 859 had not (US group). Inverse probability of treatment weighting (IPTW) and propensity score matching (PSM) were used to adjust for 14 variables and balance the two groups. Changes in nodal staging and surgical extent caused by CT were recorded. The recurrence-free survival and distant metastasis-free survival after surgery were compared between the two groups. Results: In the CT + US group, discordant nodal staging results between CT and US were observed in 94 of 584 patients (16.1%). Of them, CT accurately diagnosed nodal staging in 54 patients (57.4%), while the US provided incorrect nodal staging. Ten patients (1.7%) had a change in the extent of surgery based on CT findings. Postsurgical recurrence developed in 3.6% (31 of 859) of the CT + US group and 2.9% (17 of 584) of the US group during the median follow-up of 59 months. After adjustment using IPTW (580 vs. 861 patients), the CT + US group showed significantly higher recurrence-free survival rates than the US group (hazard ratio [HR], 0.52 [95% confidence interval {CI}, 0.29-0.96]; P = 0.037). PSM analysis (535 patients in each group) showed similar HR without statistical significance (HR, 0.60 [95% CI, 0.31-1.17]; P = 0.134). For distant metastasis-free survival, HRs after IPTW and PSM were 0.75 (95% CI, 0.17-3.36; P = 0.71) and 0.87 (95% CI, 0.20-3.80; P = 0.851), respectively. Conclusion: The addition of CT imaging for preoperative evaluation changed nodal staging and surgical extent and might improve recurrence-free survival in patients with PTC.

• Korean Journal of Child Studies
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• v.32 no.4
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• pp.115-134
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• 2011

The purpose of this study was to understand children's negative attitudes exhibited towards peers with special needs in an inclusive kindergarten, utilizing ethnographic research methodology. The subjects consisted of 54 children undergoing typical development and three children with special needs in a public kindergarten in Busan metropolitan city. Data collection was conducted by means of participant observations and interviews took place from April until November, 2009. Our results revealed that the responses of 'not acknowledging presence', 'differentiating', 'adapting them to us', 'excluding at play' were major themes in children's negative attitudes exhibited towards peers with disabilities in an otherwise ostensibly inclusive kindergarten. The response of 'not acknowledging presence' was categorized as a way of ignoring their existence, whereas 'differentiating' was categorized as stressing difference, and assuring difference. There were two characteristics related to 'adapting them to us' : adapting them to our ways, adapting them to our knowledge. Concerning 'excluding from play', four characteristics were found : excluding indirectly, excluding directly, excluding illogically, and excluding by seeking majority accord. The implications of the findings for inclusive early childhood education were discussed.

• Korean Journal of Biological Psychiatry
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• v.23 no.4
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• pp.123-129
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• 2016

Depression has a relatively high lifetime prevalence rate in spite of a genetic influence on its etiology and a high mortality rate in untreated cases. This suggests the possibility that depression gives us evolutionary benefits which we do not exactly know yet. There have been several hypotheses which tell us what evolutionary advantages depression could give us. The psychic pain hypothesis considers sad or depressed mood as a negative reward just like physical pain which we have to avoid for our protection and survival. The social rank hypothesis holds that depressed mood is very similar to the emotional state of the defeated in social competition which prevents him from further protesting or fighting that might cause additional damage to him. The inclusive fitness hypothesis views suicide as a sacrifice phenomenon to contribute to inclusive fitness. These hypotheses gives us new insights into mood disorders and also some suggestions about the conditions in which depressed mood or suicidal behaviors increase and the ways to reduce them.

• International journal of advanced smart convergence
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• v.9 no.2
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• pp.147-156
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• 2020

ACM's CSTA has drafted standards for computing curricula and recommended them to schools in the United States. The five core concepts of the US elementary school computing curriculum are computing systems, network and the Internet, data and analysis, algorithms and programming, and impacts of computing. In 2005, Korea prepared ICT education guidelines, including five fields, their subfields, and achievement criteria for each subfield. In the 2015 revised curriculum, software education was introduced and five achievement standards were set. The ACM CSTA has 18 achievement criteria up to K-2 and 21 achievement criteria up to K-5. If we compare the 39 achievement standards of the US to Korea, Korea's 2005 ICT education guidelines include 25 of these, and the 2015 revised curriculum includes 5 of them. In this study, we aim to study the CSTA achievement criteria that second graders should know and the achievement criteria that fifth graders should know. This is compared and analyzed with Korea's 2005 ICT Guidelines and 2015 Software Curriculum. In comparison with the number of achievement standards, the US elementary school's computing achievement standards are much higher than in Korea. Comparing with each standard, there are many areas that are not covered in Korean curriculum, and we can see that the 2015 curriculum has rather receded from 2005.

• Clinics in Shoulder and Elbow
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• v.19 no.2
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• pp.67-72
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• 2016

Background: The aim of this study was to analyze the questions in the shoulder and elbow section of the Korean Orthopaedic In-Training Examination (KOITE) and compare them with those of the US Orthopaedic In-Training Examination (US OITE). Methods: Twenty-nine questions in the shoulder and elbow section of the KOITE from 2010 to 2014 were analyzed and compared with those of the US OITE (80 questions) by literature review. A thorough analysis of the contents was performed after categorizing as topics, diagnostic tools, treatment modalities, taxonomic classification, and references. Results: The shoulder and elbow section of the KOITE was 5.8% weight which was similar to the US OITE (5.9%). The most commonly appearing topic was anterior labral injury (17.2%) on the KOITE compared to instability and arthritis (21.3%, each) on the US OITE. Magnetic resonance imaging was most frequently appeared imaging modality on the KOITE (41.0%) compared to the radiograph on the US OITE (43.0%). The Latarjet procedure was the most commonly asked treatment modality (22.2%) on the KOITE, whereas arthroplasty (33.3%) on the US OITE. The KOITE showed an even taxonomic classification distribution compared to the US OITE. Campbell's operative orthopaedics covered 96.6% questions as a reference on the KOITE compared to the Journal of Bone and Joint Surgery, American Volume on the US OITE, which covered 45.0%. Conclusions: This specific analysis shows us current trends of the shoulder and elbow section of the KOITE and it might be developed for use in the educational curricula for the trainee.