• The Journal of Advanced Prosthodontics
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• 제13권4호
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• pp.191-204
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• 2021

PURPOSE. The purpose of this study is to present a methodology to evaluate the accuracy of intraoral scanners (IOS) used in vivo. MATERIALS AND METHODS. A specific feature-based gauge was designed, manufactured, and measured in a coordinate measuring machine (CMM), obtaining reference distances and angles. Then, 10 scans were taken by an IOS with the gauge in the patient's mouth and from the obtained stereolithography (STL) files, a total of 40 distances and 150 angles were measured and compared with the gauge's reference values. In order to provide a comparison, there were defined distance and angle groups in accordance with the increasing scanning area: from a short span area to a complete-arch scanning extension. Data was analyzed using software for statistical analysis. RESULTS. Deviations in measured distances showed that accuracy worsened as the scanning area increased: trueness varied from 0.018 ± 0.021 mm in a distance equivalent to the space spanning a four-unit bridge to 0.106 ± 0.08 mm in a space equivalent to a complete arch. Precision ranged from 0.015 ± 0.03 mm to 0.077 ± 0.073 mm in the same two areas. When analyzing angles, deviations did not show such a worsening pattern. In addition, deviations in angle measurement values were low and there were no calculated significant differences among angle groups. CONCLUSION. Currently, there is no standardized procedure to assess the accuracy of IOS in vivo, and the results show that the proposed methodology can contribute to this purpose. The deviations measured in the study show a worsening accuracy when increasing the length of the scanning area.

• Educational Technology International
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• 제10권2호
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• pp.107-125
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• 2009

This study seeks to prove three points through the research. The first point is to examine the changes of international attitudes with actual experiences using synchronous international distance learning. The second point is to examine the effectiveness of a synchronous international distance system. And the final point is to compare international attitudes among middle school and undergraduate school students in Korea and Japan. The study used the DVTS for audio and video communication tools and automatic translating chat as a text communication tool. This combination of communication tools was very effective for students from both countries to communicate for international collaborative learning activities. The study found several interesting patterns of attitude change from the results of the study. For whole category analysis, there are positive changes in four categories of international attitudes: consciousness to foreign countries, consideration for other's viewpoints, motivation for international education, and recognition for the counterpart country. However, there was no change in the nationality category.

• 지역사회간호학회지
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• 제33권3호
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• pp.312-320
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• 2022

Purpose: This study was performed to explore the effect of the delivery format on teaching presence, learning presence, and learning outcomes in distance learning of nursing students. Methods: A descriptive survey was conducted to understand teaching presence, learning presence, and learning outcomes depending on the delivery format of distance learning. Quota sampling methodology was used to recruit 295 nursing students from all over the country, and data collection was done from July 27 to September 10, 2020. The first delivery format for distance learning was synchronous learning in which communication between the instructor and students occurred simultaneously. The second delivery format was asynchronous learning in which prerecorded videos were provided and communication did not occur simultaneously. Results: In synchronous learning, teaching presence (especially direct facilitation) and learning presence (especially emotional expression) had a statistical significance that was higher than in asynchronous learning. However, in learning outcomes, there was no statistically significant difference. There were significant positive correlations between teaching presence, learning presence, and learning outcomes, and there were significant positive correlations. Conclusion: It can be suggested that learning outcomes can be improved if presence is improved in the distance learning environment based on the results of this study. It is necessary to add contact with nursing students and instructors to improve teaching presence in the asynchronous learning, and it is necessary to help students express their emotions to improve learning presence.

• 무역학회지
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• 제45권4호
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• pp.65-81
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• 2020

Under New Climate Regime, countries are trying to enhance environmental regulations to meet international standards. This study is designed to examine the relationship between the relative level of environmental regulation of the importing countries and the export performance at the industrial level. Panel data from 2009 to 2018 was established for 12 top export industries and empirical analysis was conducted. For the analysis method, panel OLS, Hausman-Taylor, and panel GLS were used based on the results of the Hausman verification. The dependent variable is the export performance of each industry. As the independent variables, the relative level of environmental regulation, GDP per capita of the importing country, exchange rate, FTA agreement, and physical distance from the importing country were used. Results show that the relative level of environmental regulation has a negative effect on export performance of semiconductors, displays, special machines, general machines, electric appliances, and home appliances. On the other hand, there are no relationship between the relative level of environmental regulation of the importing country and export performance of automobile, petroleum refining, petrochemical, shipbuilding, and communication equipment industries.

• 디지털융복합연구
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• 제15권6호
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• pp.1-8
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• 2017

본 연구는 한국이 투자대상국인 OECD국가를 대상으로 외국인직접투자에 영향을 주는 요인을 파악하기 위하여 현지국과 투자국의 문화 거리와 부패인식지수의 차이를 활용하여 외국인직접투자에 영향을 주는 요인을 규명하였다. 연구결과 문화적 차원과 부패인식지수에 따라 외국인직접투자에 차이가 나타나는 것을 살펴볼 수 있었다. 문화적 성향에 따라 외국인직접투자가 증대될 수도 감소될 수도 있으며, 부패인식지수가 높을수록 투자가 활발하게 이루어졌다. 외국인직접투자에 영향을 주는 요인에 있어서 현지국과 투자국사이의 권력거리가 작을수록, 개인주의 대 집단주의 거리가 클수록 투자건수와 규모가 증대되는 것으로 나타났으며, 투자국의 부패인식지수가 높을 때 외국인직접투자가 증대되는 것으로 나타났다. 본 연구결과를 통하여 문화와 부패인식정도가 무역거래에 영향을 줄 수 있음을 확인함으로써 무역거래시 교역당사자간의 문화적 성향과 문화적 거리를 고려하여야 하며, 공공부패 등을 비롯한 사회적 변수를 적절하게 관리함으로써 무역 및 경제성장에 영향을 줄 수 있다는 시사점을 제시하였다.

• The Journal of Asian Finance, Economics and Business
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• 제8권2호
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• pp.151-164
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• 2021

The paper identifies the enablers (drivers) and inhibitors (barriers) influencing e-customs implementation in Vietnam (known as a developing country with a lower technological environment) along with determining the impact of e-customs on firm performance. The survey was conducted with the representatives (managers) of firms in five cities and provinces dominating Vietnam's international trade. The data was analyzed using structural equation modeling (SEM). The findings show two significant drivers (enablers) - relative advantages and national culture, while compatibility and ease of use are the barriers. Previous studies showed that cultural dimensions related to 'uncertainty acceptance' and 'individualism' encourage innovation; however, this paper demonstrates that 'uncertainty avoidance' and 'collectivism' promote e-customs deployment in Vietnam. Previously, Vietnamese culture was known for scoring high on cultural dimensions related to 'power distance' and 'short-term orientation'. However, today, as an emerging country, Vietnamese has switched to 'low distance' and 'long-term orientation', especially in terms of e-customs innovation. Additionally, the paper also emphasized that e-customs implementation had a positive influence on firm performance in Vietnam. Based on the results of the paper, policy-makers can devise essential solutions to enhance e-customs implementation as well as managers of firms can set-up strategies to adapt to the modernized environment.

• The Journal of Asian Finance, Economics and Business
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• 제9권8호
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• pp.1-6
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• 2022

This paper uses the gravity model estimated by the random effect method to analyze the factors affecting Vietnam's coffee export turnover for the period 2007-2020 major markets according to statistics from the General Statistics Office and the General Department of Customs. Coffee export turnover was collected from the General Statistics Office, General Department of Customs, and Vietnam Cacao Coffee Association. The authors calculated the price of coffee based on output and export value from data on coffee export turnover; the authors calculated the economic gap based on population and Gross Domestic Product data (reference: geographic distance metrics on the website: http://www.distancefromto.net/countries.php) and other data was collected based on the databases of the Food and Agriculture Organization of the United Nations, the International Monetary Fund, and World Bank organizations. The results of the study show that from 2007 to 2020, the factors of Vietnam's export price of coffee, geographical distance, Gross Domestic Product of the importing country and Gross Domestic Product of Vietnam, the population of Vietnam, the economic gap between Vietnam and the importing country, the openness of the economy, all have an impact on Vietnam's coffee export turnover. Finally, some conclusions about the policy's impact are made based on the empirical results of the paper.

• 대한임베디드공학회논문지
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• 제19권2호
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• pp.91-99
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• 2024

Collision avoidance system is important to improve the robustness and functional safety of autonomous vehicles. This paper proposes an object-level distance estimation method to develop a collision avoidance system, and it is applied to golfcarts utilized in country club environments. To improve the detection accuracy, we continually trained an object detection model based on pseudo labels generated by a pre-trained detector. Moreover, we propose object-aware depth estimation (OADE) method which trains a depth model focusing on object regions. In the OADE algorithm, we generated dense depth information for object regions by utilizing detection results and sparse LiDAR points, and it is referred to as object-aware LiDAR projection (OALP). By using the OALP maps, a depth estimation model was trained by backpropagating more gradients of the loss on object regions. Experiments were conducted on our custom dataset, which was collected for the travel distance of 22 km on 54 holes in three country clubs under various weather conditions. The precision and recall rate were respectively improved from 70.5% and 49.1% to 95.3% and 92.1% after the continual learning with pseudo labels. Moreover, the OADE algorithm reduces the absolute relative error from 4.76% to 4.27% for estimating distances to obstacles.

• 한국간호교육학회지
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• 제5권2호
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• pp.165-176
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• 1999

The goal of women's health education can be defined as improvement of the quality of their life during entire life cycle. In Korean society, women's well-being is very important to themselves as well as their families, communities. and country. Thus it is important to systematize information on women's health education. These systematized information can be used in preparation of coming 21st century called information era. Unfortunately there have been few studies in women's health education research in Korea especially distance education for women's health related with korean socio-cultural background, etc. Distance education has been internationally used in a variety of settings as a means of providing health education information. The objective of this study was to apply and evaluate a multimedia videoconferencing on women's health distance teaching-learning process. In this study I'd like to design multimedia digital educational material used in the distance teaching-learning process for women's health, and to practice a multimedia videoconferencing on women's health distance teaching-learning processs. The procedures of this study were summarized as follows ; 1. Analysis of subjects' characteristics and education contents and for women's health. 2. Design of a multimedia videoconferencing on women's health distance teaching-learning process. 3. Development of women's health distance teaching-1earning process. 4. Evaluation of developed digital multimedia and distance teaching-learning process related with women's health These results will be used in development of the distance-learning education program for improving Korean women's health. Findings su99est that the advanced methodologies for designing and evaluating the women's health distance teaching-learning programs be obtained through the collaboration with other field's staffs.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2934-2940
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• 2011

The railway system in Korea is developing more and more rapidly. After development the next generation hi-speed train(HEMU-400X), Korea can compete against developed country. But, speed increasing will cause the greater rolling and aero dynamic noise. In this study shows that measurement noise of the KTX train by 300kn/h class, and KTX-Sancheon train by 350km/h class. The measurements are carried out on open area and noise protection barrier installed area. The microphones were placed at a distance of 3m from the center line of the track at a height of 0.5m above the upper surface of the rail and at a distance of 7.5m from the center line of the track at a height of each 0.6m above(Max 3.6m) the upper surface of the rail. One microphone was placed at a distance of 25m for check the environmental noise.