• Asia Marketing Journal
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• v.12 no.2
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• pp.1-25
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• 2010

Motion pictures are so typical experience goods that consumers tend to look for more credible information. Hence, movie audiences consider movie viewers' reviews more important than the information provided by the film distributor. Recently many portal sites allow consumers to post their reviews and opinions so that other people check the number of consumer reviews and scores before going to the theater. There are a few previous researches studying the electronic word of mouth(eWOM) effect in the movie industry. They found that the volume of eWOM influenced the revenue of the movie significantly but the valence of eWOM did not affect it much (Liu 2006). The goal of our research is also to investigate the eWOM effects in general. But our research is different from the previous studies in several aspects. First, we study the eWOM effect in Korean movie industry. In other words, we would like to check whether we can generalize the results of the previous research across countries. The similar econometric models are applied to Korean movie data that include 746,282 consumer reviews on 439 movies. Our results show that both the valence(RATING) and the volume(LNMSG) of the eWOM influence weekly movie revenues. This result is different from the previous research findings that the volume only influences the revenue. We conjectured that the difference of self construal between Asian and American culture may explain this difference (Kitayama 1991). Asians including Koreans have more interdependent self construal than American, so that they are easily affected by other people's thought and suggestion. Hence, the valence of the eWOM affects Koreans' choice of the movie. Second, we find the critical defect of the previous eWOM models and, hence, attempt to correct it. The previous eWOM model assumes that the volume of eWOM (LNMSG) is an independent variable affecting the movie revenue (LNREV). However, the revenue can influence the volume of the eWOM. We think that treating the volume of eWOM as an independent variable a priori is too restrictive. In order to remedy this problem, we employed a simultaneous equation in which the movie revenue and the volume of the eWOM can affect each other. That is, our eWOM model assumes that the revenue (LNREV) and the volume of eWOM (LNMSG) have endogenous relationship where they influence each other. The results from this simultaneous equation model showed that the movie revenue and the eWOM volume interact each other. The movie revenue influences the eWOM volume for the entire 8 weeks. The reverse effect is more complex. Both the volume and the valence of eWOM affect the revenue in the first week, but only the volume affect the revenue for the rest of the weeks. In the first week, consumers may be curious about the movie and look for various kinds of information they can trust, so that they use the both the quantity and quality of consumer reviews. But from the second week, the quality of the eWOM only affects the movie revenue, implying that the review ratings are more important than the number of reviews. Third, our results show that the ratings by professional critics (CRATING) had negative effect to the weekly movie revenue (LNREV). Professional critics often give low ratings to the blockbuster movies that do not have much cinematic quality. Experienced audiences who watch the movie for fun do not trust the professionals' ratings and, hence, tend to go for the low-rated movies by them. In summary, applied to the Korean movie ratings data and employing a simultaneous model, our results are different from the previous eWOM studies: 1) Koreans (or Asians) care about the others' evaluation quality more than quantity, 2) The volume of eWOM is not the cause but the result of the revenue, 3) Professional reviews can give the negative effect to the movie revenue.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.3
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• pp.204-214
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• 2023

The occlusal treatment including prosthetic treatment should be considered when the pathologic symptom was observed with the excessive discrepancy between the centric relation occlusion (CRO) and the maximum intercuspal position (MIP). Through careful diagnosis, the malocclusion and interarch relationship can be analyzed, and occlusal adjustment, restorative treatment, orthodontic therapy, or orthognathic surgery can be performed depending on the degree of disharmony. The patient in this case report complained the unstable occlusion and loss of masticatory function that had been occurring for several years. At the time of the visit, the patient showed severe occlusal disharmony, with only the upper right second molar contacting the lower jaw at the maximum intercuspal position. Based on the analysis of the occlusion, it was difficult to solve the problem with just occlusal adjustment or restorative treatment. In addition, the patient had the skeletal class II malocclusion between the upper and lower jaws. Therefore, for resolving the severe skeletal class II malocclusion, pre- and post-orthodontic treatment, bilateral sagittal split ramus osteotomy (BSSRO) was performed. After that, the occlusal adjustment was performed for stable occlusion, and the missing teeth area was restored with dental implants. During the follow-up period, a periodic follow-up visits and additional occlusal adjustments were performed to achieve a stable centric occlusion and harmonious anterior and lateral guidance. As a result, the final prosthodontic treatment was completed, and the patient's masticatory function was restored.

• Korean Journal of Remote Sensing
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• v.39 no.5_3
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• pp.1031-1042
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• 2023

In this study, a deep learning model was developed to predict the yield of cabbage and radish, one of the five major supply and demand management vegetables, using satellite images of Landsat 8. To predict the yield of cabbage and radish in Gangwon-do from 2015 to 2020, satellite images from June to September, the growing period of cabbage and radish, were used. Normalized difference vegetation index, enhanced vegetation index, lead area index, and land surface temperature were employed in this study as input data for the yield model. Crop yields can be effectively predicted using satellite images because satellites collect continuous spatiotemporal data on the global environment. Based on the model developed previous study, a model designed for input data was proposed in this study. Using time series satellite images, convolutional neural network, a deep learning model, was used to predict crop yield. Landsat 8 provides images every 16 days, but it is difficult to acquire images especially in summer due to the influence of weather such as clouds. As a result, yield prediction was conducted by splitting June to July into one part and August to September into two. Yield prediction was performed using a machine learning approach and reference models , and modeling performance was compared. The model's performance and early predictability were assessed using year-by-year cross-validation and early prediction. The findings of this study could be applied as basic studies to predict the yield of field crops in Korea.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.6
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• pp.583-603
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• 2023

Recently, the advancement of mechanical tunnel boring machine (TBM) technology and the characteristics of subsea railway tunnels subjected to hydrostatic pressure have led to the widespread application of shield TBM methods in the design and construction of subsea railway tunnels. Subsea railway tunnels are exposed in a constant pore water pressure and are influenced by the amplification of seismic waves during earthquake. In particular, seismic loads acting on subsea railway tunnels under various ground conditions such as soft ground, soft soil-rock composite ground, and fractured zones can cause significant changes in tunnel displacement and stress, thereby affecting tunnel safety. Additionally, the dynamic response of the ground and tunnel varies based on seismic load parameters such as frequency characteristics, seismic waveform, and peak acceleration, adding complexity to the behavior of the ground-tunnel structure system. In this study, a finite difference method is employed to model the entire ground-tunnel structure system, considering hydrostatic pressure, for the investigation of dynamic behavior of subsea railway tunnel during earthquake. Since the key factors influencing the dynamic behavior during seismic events are ground conditions and seismic waves, six analysis cases are established based on virtual ground conditions: Case-1 with weathered soil, Case-2 with hard rock, Case-3 with a composite ground of soil and hard rock in the tunnel longitudinal direction, Case-4 with the tunnel passing through a narrow fault zone, Case-5 with a composite ground of soft soil and hard rock in the tunnel longitudinal direction, and Case-6 with the tunnel passing through a wide fractured zone. As a result, horizontal displacements due to earthquakes tend to increase with an increase in ground stiffness, however, the displacements tend to be restrained due to the confining effects of the ground and the rigid shield segments. On the contrary, peak compressive stress of segment significantly increases with weaker ground stiffness and the effects of displacement restrain contribute the increase of peak compressive stress of segment.

• The Journal of Korean Society for Radiation Therapy
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• v.35
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• pp.41-51
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• 2023

Purpose: This study compares and analyzes the image quality of 3D-CBCT(Cone Beam Computed-Tomography) and Gated CBCT according to baseline changes during SBRT(Stereotactic Body RadioTherapy) in lung cancer patients to find a useful CBCT method for correcting movement due to breathing Materials and methods : Insert a solid tumor material with a diameter of 3 cm into the QUASAR^TM phantom. 4-Dimentional Computed-Tomography(4DCT) images were taken with a speed of the phantom at period 3 sec and a maximum amplitude of 20 mm. Using the contouring menu of the computerized treatment planning system Eclipse^TM Gross Tumor Volume was outlined on solid tumor material. Set-up the same as when acquiring a 4DCT image using Truebeam STx^TM, breathing patterns with baseline changes of 1 mm, 3 mm, and 5 mm were input into the phantom to obtain 3D-CBCT (Spotlight, Full) and Gated-CBCT (Spotlight, Full) images five times repeatedly. The acquired images were compared with the Signal-to-Noise Ratio(SNR), Contrast-to-Noise Ratio(CNR), Tumor Volume Length, and Motion Blurring Ratio(MBR) based on the 4DCT image. Results: The average Signal-to-Noise Ratio, Contrast-to-Noise Ratio, Tumor Volume Length and Motion Blurring Ratio of Spotlight Gated CBCT images were 13.30±0.10%, 7.78±0.16%, 3.55±0.17%, 1.18±0.06%. As a result, Spotlight Gated-CBCT images according to baseline change showed better values than Spotligtht 3D-CBCT images. Also, the average Signal-to-Noise Ratio, Contrast-to-Noise Ratio, Tumor Volume Length and Motion Blurring Ratio of Full Gated CBCT images were 12.80±0.11%, 7.60±0.11%, 3.54±0.16%, 1.18±0.05%. As a result Full GatedCBCT images according to baseline change showed better values than Full 3D-CBCT images. Conclusion : Compared to 3D-CBCT images, Gated-CBCT images had better image quality according to the baseline change, and the effect of Motion Blurring Artifacts caused by breathing was small. Therefore, it is considered useful to image guided using Gated-CBCT when a baseline change occurs due to difficulty in regular breathing during SBRT that exposes high doses in a short period of time

• Korean small business review
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• v.31 no.2
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• pp.85-102
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• 2009

With the continued globalization of world markets, transfer pricing has become one of the dominant sources of controversy in international taxation. Transfer pricing is the process by which a multinational corporation calculates a price for goods and services that are transferred to affiliated entities. Consider a Korean electronic enterprise that buys supplies from its own subsidiary located in China. How much the Korean parent company pays its subsidiary will determine how much profit the Chinese unit reports in local taxes. If the parent company pays above normal market prices, it may appear to have a poor profit, even if the group as a whole shows a respectable profit margin. In this way, transfer prices impact the taxable income reported in each country in which the multinational enterprise operates. It's importance lies in that around 60% of international trade involves transactions between two related parts of multinationals, according to the OECD. Multinational enterprises (hereafter MEs) exert much effort into utilizing organizational advantages to make global investments. MEs wish to minimize their tax burden. So MEs spend a fortune on economists and accountants to justify transfer prices that suit their tax needs. On the contrary, local governments are not prepared to cope with MEs' powerful financial instruments. Tax authorities in each country wish to ensure that the tax base of any ME is divided fairly. Thus, both tax authorities and MEs have a vested interest in the way in which a transfer price is determined, and this is why MEs' international transfer prices are at the center of disputes concerned with taxation. Transfer pricing issues and practices are sometimes difficult to control for regulators because the tax administration does not have enough staffs with the knowledge and resources necessary to understand them. The authors examine transfer pricing practices to provide relevant resources useful in designing tax incentives and regulation schemes for policy makers. This study focuses on identifying the relevant business and environmental factors that could influence the international transfer pricing of MEs. In this perspective, we empirically investigate how the management perception of related variables influences their choice of international transfer pricing methods. We believe that this research is particularly useful in the design of tax policy. Because it can concentrate on a few selected factors in consideration of the limited budget of the tax administration with assistance of this research. Data is composed of questionnaire responses from foreign firms in Korea with investment balances exceeding one million dollars in the end of 2004. We mailed questionnaires to 861 managers in charge of the accounting departments of each company, resulting in 121 valid responses. Seventy six percent of the sample firms are classified as small and medium sized enterprises with assets below 100 billion Korean won. Reviewing transfer pricing methods, cost-based transfer pricing is most popular showing that 60 firms have adopted it. The market-based method is used by 31 firms, and 13 firms have reported the resale-pricing method. Regarding the nationalities of foreign investors, the Japanese and the Americans constitute most of the sample. Logistic regressions have been performed for statistical analysis. The dependent variable is binary in that whether the method of international transfer pricing is a market-based method or a cost-based method. This type of binary classification is founded on the belief that the market-based method is evaluated as the relatively objective way of pricing compared with the cost-based methods. Cost-based pricing is assumed to give mangers flexibility in transfer pricing decisions. Therefore, local regulatory agencies are thought to prefer market-based pricing over cost-based pricing. Independent variables are composed of eight factors such as corporate tax rate, tariffs, relations with local tax authorities, tax audit, equity ratios of local investors, volume of internal trade, sales volume, and product life cycle. The first four variables are included in the model because taxation lies in the center of transfer pricing disputes. So identifying the impact of these variables in Korean business environments is much needed. Equity ratio is included to represent the interest of local partners. Volume of internal trade was sometimes employed in previous research to check the pricing behavior of managers, so we have followed these footsteps in this paper. Product life cycle is used as a surrogate of competition in local markets. Control variables are firm size and nationality of foreign investors. Firm size is controlled using dummy variables in that whether or not the specific firm is small and medium sized. This is because some researchers report that big firms show different behaviors compared with small and medium sized firms in transfer pricing. The other control variable is also expressed in dummy variable showing if the entrepreneur is the American or not. That's because some prior studies conclude that the American management style is different in that they limit branch manger's freedom of decision. Reviewing the statistical results, we have found that managers prefer the cost-based method over the market-based method as the importance of corporate taxes and tariffs increase. This result means that managers need flexibility to lessen the tax burden when they feel taxes are important. They also prefer the cost-based method as the product life cycle matures, which means that they support subsidiaries in local market competition using cost-based transfer pricing. On the contrary, as the relationship with local tax authorities becomes more important, managers prefer the market-based method. That is because market-based pricing is a better way to maintain good relations with the tax officials. Other variables like tax audit, volume of internal transactions, sales volume, and local equity ratio have shown only insignificant influence. Additionally, we have replaced two tax variables(corporate taxes and tariffs) with the data showing top marginal tax rate and mean tariff rates of each country, and have performed another regression to find if we could get different results compared with the former one. As a consequence, we have found something different on the part of mean tariffs, that shows only an insignificant influence on the dependent variable. We guess that each company in the sample pays tariffs with a specific rate applied only for one's own company, which could be located far from mean tariff rates. Therefore we have concluded we need a more detailed data that shows the tariffs of each company if we want to check the role of this variable. Considering that the present paper has heavily relied on questionnaires, an effort to build a reliable data base is needed for enhancing the research reliability.

• Journal of Korean Academy of Nursing
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• v.4 no.3
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• pp.33-56
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• 1974

간호를 장래의 전문직으로 택하려고 공부하는 간호학생들은 완전한 성인으로서의 발달 과정중 후기 성년기에 속한다. 이시기는 자아를 발견하고 인간이 무엇을 믿으며 인간의 가치가 무엇인가를 추구하는 중요한 시기이다. 다시 말해서 어른과 어린이의 과도기에 서서 자신의 이상적 가치와 기성사회의 기존 가치를 잘 융화시켜 독립된 인간으로서 성숙하려는 노력의 시기이다. 그러므로 성년기의 갈등은 인생의 어느 시기보다도 그 정도가 심하게 나타난다. 간호학생들은 이상의 일반적인 성년기 발달의 요구 외에도 간호대학이라는 특수한 배움의 여건 때문에 좀 더 심각한 문제에 대두된다. 특히 소아과 간호대학이라는 실습환경은 여러 가지 복잡한 병실 사정으로 많은 긴장감을 주는 학습경험이다. 어린이의 간호에는 그들의 발달과정에 따른 다양한 역활이 요구된다. 또한 병원이라는 낯선 환경과 어머니를 떨어져야하는 두려움으로 불안한 어린이와 그 어린이의 불안과 두려움으로 인해 우울과 죄의식에 있는 어머니의 간호는 여러 면에서 성년기 학생들에게 긴장감을 일으키게 하는 요인이 된다. 본 연구의 문헌조사는 주로 미국 문헌에 나타난 간호 대학생들의 성년기 성숙을 위한 발달의 요구와, 소아병실의 복잡한 여건으로 발생되는 긴장감을 다루고 있다. 문헌을 기초로 하여 저자는 긴장감을 주는 간호활동을 크게 다섯 부군으로 묶었다. 1. 어린이 환자의 신체적 간호, 2. 어린이 환자나 부모와의 원만한 대화와 상호관계를 위한 간호활동 3. 소아병실에서 요구되는 다양한 간호원의 역활 4. 어린이나 부모의 간호에 대한 의뢰심 5. 간호의 가치나 이상적 간호. 연구방법으로는 49개의 폐쇄식 질문 항목을 가진 질문지를 사용하였다. 질문 항목들은 문헌연구에서 소아과 간호학 실습시 학생들이 긴장감을 느낀다고 밝혀진 내용들이 다. 학생들은 자신의 경험을 "긴장감이 없었다. ""긴장감이 있었다. ""심한 긴장감이 있었다. ""실습 중 경험이 없었다. "의 사항 중 택일을 하게 되어 있다. 연구대상으로는 모 대학교 간호대학 학생으로 산부인과 간호학 실습을 마친 후 소아과 간호학 실습 8주를 완료한 4학년 학생 42명이었다. 자료분석의 결과는 대부분의 학생들에게 소아과 간호학 실습은 긴장감을 주는 경험이 있다고 나타났다. 다음은 연구결과 주목할만한 몇 가지 사항들이다. 1. 어린이 환자의 신체적 간호는 성년기 학생들에게 긴장감을 주는 실습 경험이었다. 특별히 심하게 긴장감을 주었던 간호활동은 어린이환자의 상태가 중한 경우로, 장기간 앓는 아이, 선천성 기형이 있는 아이, 회복이 불가능하여 죽게될 아이나 사망하는 경우의 어린이 간호였다. 이 결과는 간호학의 기본과정 즉, 기초간호학이나 내 외과 간호학 실습만으로 소아과 간호학 실습을 위한 충분한 준비가 되지 못한다는 것을 뜻 할 수도 있다. 한편, 문헌연구에서 밝힌바와 같이 어리고 연약해 보이는 어린이들의 신체조건이 학생들의 간호활동을 어렵게 하는 경우도 될 수 있겠다. 2. 간호학생들의 어린이 환자와의 대화나 원만한 인간관계에서의 긴장감은 이 연구결과로 평가나 제언이 힘들다. 조사결과에서 학생들은 주로 어린이의 상태가 좋지 않은 경우에 심한 긴장감을 가졌고 일반적인 간호의 경우에는 별로 긴장감이 없었다. 이것은 질병의 상태나 화제, 이야기 할 때의 상황에 따라 긴장감의 여부가 달라질 수 있다는 결론이 되겠다. 3. 소아병실에서의 다양한 역활을 수행하는 것은 비교적 긴장감이 많이 생기는 간호활동으로 나타났다. 그러나 재미있는 사실은 학생들이 간호원으로서의 전문가적인 입장에서, 환자나 보호자를 가르칠때는 별로 문제가 없었으나 어린이 기르는 방법이나 어린이 이해면에서 좀 더 잘 안다고 생각되는 어머니가 지켜 볼때의 어린이 간호에는 긴장감을 가진다는 사실이다. 이것은 Jewett의 연구에서 밝힌바와는 상반되는 결과다. 그의 연구에서 학설들은 부모나 어머니들에 의해 전문가로서 인정받고 기대되는 경우가 제일 어려운 경험이 있다고 밝혔다. 4. 어린이 환자나 그들 부모의 간호에 대한 의뢰심은 학생들에게 심한 긴장감을 주는 경험이 있다. 특히 신체적 간호에 대해 의뢰하는 경우에는 더 심한 긴장감을 준다고 표현한다. 일반적으로 부모가 병실에 상주하는 경우에는 그들의 의뢰심이 심하며 이것은 학생들에게 감당하기 힘든 긴장과 어려움을 주게된다. 왜냐하면 성년기의 학생들은 그들 자신이 먼저 타인에게서 이해받기를 원하며 또 관용을 베풀어주기를 원하는데 그것을 남에게 주어야 하는 입장은 학생들을 긴장되게 하는 실습활동인 것이다. 5. 학생들은 그들이 배운 간호의 이상이나 가치가 실습지에서의 여러 경우와 맞지 않는 것을 보았을 때 극심한 긴장감을 갖는다고 밝혔다. 의사나 병원 행정의 사실이 자신의 이상과 맞지 않는다는 것보다는 간호원의 간호업무의 차이에서 더 비판적인 반응을 보였다. 대부분의 성년기 학생들은 그들의 이상적인 간호원상을 그들의 선배나 실무 간호원 중에서 찾으려는 시기에 그들의 간호활동이 이론과 다른 점이나 학생 자신의 소아과 간호의 가치와 다른 것을 보았을 때는 심한 반감과 긴장감을 갖게된다. 이 문제는 어린 사람이 윗 어른과 함께 동료의식을 갖고 일하기 어려운 한국적 사회구조 때문에 더 심하게 긴장감을 주는 경험인지도 모른다. 선배 간호원의 전문인으로서의 권위와 어린이 환자 보호자의 어른으로서의 권위 사이에서 자신의 이상과 가치의 추구는 용이하지 않으며 내적 갈등은 어쩔수 없는 일 일 것이다. 6. 대부분 높은 백분율의 긴장 반응은 죽음이나 환자의 사망에 관련된 간호활동 항목에서 나타났다. 이 연구의 대상 학생들은 2, 3학년에서 죽음에 대한 강의를 들었지만 이 연구 결과에 의하면 충분한 학습 경험이 주어진 것 같지 않다. 어떠한 경우의 죽음에라도 어린이 환자나 그 보호자들의 심리를 잘 이해하고 반응을 잘 관찰해서 적절한 간호를 해 줄 수 있는 다양한 방법의 학습 경험이 필요하다고 보겠다. 7. 학생들의 긴장도가 어린이 간호에 더 심한가, 보호자 간호에 더 심한가를 알기 위한 비교 결과는 비교적 비슷한 정도로 나타났다. 8. 학생들의 소아과 간호학 실습시의 긴장도는 과거의 병실 실습기간의 장, 단이나 가정에서의 어린인 간호의 경험과는 별 연관성이 없었다. 연구의 대상자가 적기 때문에 단정을 하기는 힘이 들지만 소아과 간호학 실습이 다른 병실의 실습과는 분리되어서 완전히 다르게 다루어 져야만 하며 간호교육자들의 주의 깊은 관심과 노력이 필요한 실습교육이 라 하겠다. 이상의 전반적인 고찰에 의하면 한국 성년기 간호학생들의 소아과 간호학 실습은 미국의 경우와 마찬가지로 긴장감을 주는 경험이다. 문화배경의 다른 점은 무시하고라도 Davis와 Oleson이 결론한 바와 같이 "간호대 학생은 어디를 막론하고 다 같은 성격과 문제를 가지고 있다. " 앞으로 보다 효과적인 학생들의 소아과 간호학 실습을 위한 연구를 위해 다음의 몇 가지를 본 연구의 결과를 가지고 제언한다. 1. 보다 여러 지역에서 다양한 교육 방법을 가진 학교의 학생을 대상으로 한 연구의 필요성. 2. 학생들이 실습 전 선입견이나 이미 들어서 생긴 긴장감의 개입 여부를 밝힐 수 있는 연구. 3. 학생 개인의 과거 경침이 긴장감 유발에 미치는 영향을 위한 연구 4. 이 연구의 결과를 입증할 수 있는 종단적 연구. 5. 이 연구에서 나타난 긴장감이 학습 행위에 미치는 영향을 알기 위한 관찰적 연구. 이 연구를 위해 많은 도움을 주셨던 보스턴대학의 Dr. Kennedy와 연세대학의 여러 선생님께 심심한 감사를 드립니다.

• Clinical and Experimental Pediatrics
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• v.48 no.7
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• pp.737-744
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• 2005

Purpose : Infants and children with cardiovascular diseases often present with respiratory symptoms. However, missed or delayed evaluation for potential airway problem may complicate overall prognosis. The aim of this study is to determine the clinical characteristics of these patients and explore the cause of airway problem. Methods : We reviewed the medical records of 64 patients(M : F=33:31, mean age : $6.3{\pm}7.5$ months) whose airway problems were proven by computed tomography or bronchoscopy in perioperative periods at the Asan Medical Center from January 1997 to June 2004. Patients were divided into two groups based on the duration of ventilator care : ${\leq}7$ days(group 1 : 23 cases, M : F=10 : 13) and >7 days(group 2 : 41 cases, M : F=23 : 18). Results : The patients in group 2 significantly developed more post-operative respiratory symptoms than group 1(P<0.001) and had more airway problems including extrinsic obstruction, intrinsic anomaly, and combined problem than group 1 although not significantly different(P=0.082). Among underlying diseases, the most common diseases were vascular anomaly(26.2 percent) and aortic arch anomaly(26.2 percent) in group 1 and pulmonary atresia with ventricular septal defect(22.4 percent) in group 2. The most frequent respiratory symptoms were recurrent wheezing pre-operatively and failure of ventilator weaning post-operatively. The major types of airway anomaly were tracheomalacia and tracheal stenosis(in each case 18.2 percent). Nineteen patients with persistent airway problems underwent aortopexy or other vascular correction. Of the 19 patients, 13(68.4 percent) were improved, but 2 failed in weaning ventilator and 4 died of non-airway problems. Conclusion : Early evaluation and treatment for potential airway problems may affect natural or surgical prognosis in patients with cardiovascular diseases presenting with respiratory symptoms.

• Tuberculosis and Respiratory Diseases
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• v.65 no.3
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• pp.177-182
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• 2008

Background: Isoniazid (INH, H) is a key drug of the standard first-line regimen for the treatment of tuberculosis (TB), yet some reports have suggested that treatment efficacy was maintained even though INH was omitted from the treatment regimen. Methods: One hundred forty C57BL/6 mice were infected with the H37Rv strain of M. tuberculosis with using a Glas-Col aerosol generation device, and this resulted in depositing about 100 bacilli in the lung. Four weeks after infection, anti-TB treatment was initiated with varying regimens for 4-8 weeks; Group 1: no treatment (control), Group 2 (4HREZ): 4 weeks of INH, rifampicin (R), pyrazinamide (Z) and ethambutol (E), Group 3: 1HREZ/3REZ, Group 4: 4REZ, Group 5: 4HREZ/4HRE, Group 6: 1HREZ/3REZ/4RE, and Group 7: 4REZ/4RE. The lungs and spleens were harvested at several time points until 28 weeks after infection, and the colony-forming unit (CFU) counts were determined. Results: The CFU counts increased steadily after infection in the control group. In the 4-week treatment groups (Group 2-4), even though the culture was negative at treatment completion, the bacilli grew again at the 12-week and 20-week time points after completion of treatment. In the 8-week treatment groups (Groups 5-7), the bacilli did not grow in the lung at 4 weeks after treatment initiation and thereafter. In the spleens of Group 7 in which INH was omitted from the treatment regimen, the culture was negative at 4-weeks after treatment initiation and thereafter. However, in Groups 5 and 6 in which INH was taken continuously or intermittently, the bacilli grew in the spleen at some time points after completion of treatment. Conclusion: TThe exclusion of INH from the standard first-line regimen did not affect the treatment outcome in a murine model of TB in the early stage of disease. Further studies using a murine model of chronic TB are necessary to clarify the role of INH in the standard first-line regimen for treating TB.

• Tuberculosis and Respiratory Diseases
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• v.49 no.1
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• pp.37-48
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• 2000

Backgrounds : The pathophysiology of chronic airflow obstruction, such as bronchial asthma, is characterized by mucus hypersecretion, goblet cell hyperplasia(GCH), smooth muscle hypertrophy, and inflammatory cells infiltration. In fatal asthma patients, one distinct findings is mucus hypersecretion due to GCH. However, the mechanisms of GCH in these hypersecretory diseases remain still unknown. In this study, a rat model was rapidly induced with GCH by instillation of $TiO_2$, intratracheally. We intend to confirm GCH and association of concomitant inflammatory cells infiltration and to observe the effect of potent antiinflammatory agent, that is dexamethasone, on GCH with inflammatory cells. Methods : Twenty-one 8-weeks-old male Sprague-Dawley rats were divided into three groups. Endotoxinfree water was instilled intratracheally in group 1(control) ; $TiO_2$, was instilled in the group 2 ; and dexamethasone was injected intraperitoneally to group 3 before $TiO_2$ instillation. After 120 hours, all rats were sacrificed, and trachea, bronchi, and lungs were resected respectively. These tissues were made as paraffin blocks and stained as PAS for goblet cells and Luna stain for eosinophils. We calculated the ratio of goblet cell to respiratory epithelium and number of infiltrated eosinophils from each tissue. Results : (1) Fraction of goblet cells was significantly increased in group 2 than in group 1 in the trachea and in the main bronchus. (10.19$\pm$11.33% vs 4.09$\pm$8.28%, p<0.01 and 34.09$\pm$23.91% vs 3.61$\pm$4.84%, p<0.01, respectively). (2) Eosinophils were significantly increased in the airway of group 2 than that of group 1. (5.43$\pm$3.84% vs 0.17$\pm$0.47 in trachea and 47.71$\pm$16.91 vs 2.71$\pm$1.96 in main bronchi). (3) There was a positive correlation between goblet cells and eosinophils(r=0.719, p=0.001). (4) There was significant difference in the decrease of goblet cells after dexamethasone injection between group 2 and group 3 (p<0.01). Also, infiltration of eosinophils was suppressed by dexamethasone. Conclusion : We made an animal model of $TiO_2$-induced goblet cell hyperplasia. GCH was observed mainly in the main bronchi with concomitant eosinophilic infiltration. Both goblet cell hyperplasia and eosinophilic infiltration were suppressed by dexamethasone. This animal model may serve as a useful tool in understanding of the mechanism of GCH in chronic airway diseases.