• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.3
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• pp.75-86
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• 1999

An analysis model is developed to evaluate the dynamic responses of a bridge system under seismic excitations, in which pounding actions between girders are considered in addition to other phenomena such as nonlinear pier motion, rotational and translational motions of foundations. The model also considers the abutment and restrainers connecting adjacent girders to prevent the unseating failures. Using the developed model, the longitudinal dynamic behaviors of a bridge system are examined for various peak ground accelerations, and the effects of the applied restrainers are investigated. It is found that the restrainers reduce the relative displacement with the shorter clearance length as well as the higher stiffness of the restrainers for moderate excitations. However, in the region with strong excitations the restrainers may yield due to the large relative displacement. Therefore, the extension of support length in addition to restrainers may need to prevent the unseating failure more effectively.

• Journal of the Korea Fashion and Costume Design Association
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• v.11 no.1
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• pp.53-62
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• 2009

Through the result of the investigation on costumes in Bulgarian regions, the main factors for the formation of Bulgarian folk costume and its kinds and history have been found out so far as follows. Alhtough varying according to the district and climate, Bulgarian folk costumes have some general features determined by the material, the pattern, the application. For women, Bulgarian costume consists of a white shirt, a single or double apron unique depending on each region(Bruchnick), a basic dress called a tunic (Soukman), and an open-tunic typed coat (saya). The main factors for the formation of Bulgarian folk costume have been under the influence of natural and environmental features and historical streams resulting from its geographical location. Bulgaria is agriculture-oriented society based on a continental climate. Accordingly, as for the classification of costumes, body-fit clothes, such as shirts and jackets which developed in Europe and fit the body shape, have featured in Bulgaria. Besides, Bulgaria was under the rule of Turk for a long time at the end of the Middle Age. Having been influenced a lot those days, its folk costume shows Turkish elements now. With geographical features, it was found that the southern area was influenced most by Turkey and Greece, and the types of folk costumes in Europe developed mainly from the northern area. The adaptation of traditional costume forms to the new cultural and progressive principles of appeal nowadays needs knowledge, as well as feeling. Finding the right measure and proportions of using old ethnic elemints in contemporary clothing is the prerequisite of successful design.

• Progress in Medical Physics
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• v.33 no.4
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• pp.80-87
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• 2022

Purpose: Proton therapy has different relative biological effectiveness (RBE) compared with X-ray treatment, which is the standard in radiation therapy, and the fixed RBE value of 1.1 is widely used. However, RBE depends on a charged particle's linear energy transfer (LET); therefore, measuring LET is important. We have developed a LET measurement method using the inefficiency characteristic of an EBT3 film on a proton beam's Bragg peak (BP) region. Methods: A Gafchromic EBT3 film was used to measure the proton beam LET. It measured the dose at a 10-cm pristine BP proton beam in water to determine the quenching factor of the EBT3 film as a reference beam condition. Monte Carlo (MC) calculations of dose-averaged LET (LET_d) were used to determine the quenching factor and validation. The dose-averaged LETs at the 12-, 16-, and 20-cm pristine BP proton beam in water were calculated with the quenching factor. Results: Using the passive scattering proton beam nozzle of the National Cancer Center in Korea, the LET_d was measured for each beam range. The quenching factor was determined to be 26.15 with 0.3% uncertainty under the reference beam condition. The dose-averaged LETs were measured for each test beam condition. Conclusions: We developed a method for measuring the proton beam LET using an EBT3 film. This study showed that the magnitude of the quenching effect can be estimated using only one beam range, and the quenching factor determined under the reference condition can be applied to any therapeutic proton beam range.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1377-1382
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• 2011

Recently, alternative and novel energy resources have been developed for use in the future because of the current environmental problems and exhaustion of fossil energy resources. Hydrogen energy has many merits, such as its environmental friendliness, easy storage, and easy production, but it also has disadvantages, in that it is highly combustible and explosive. In this study, a test procedure using a simple SP test under highly pressurized hydrogen gas conditions was established. In order to evaluate its applicability, SP tests were carried out using a stainless steel (SUS316L) sample under atmospheric, pressurized helium, and pressurized hydrogen gas conditions. The results under the pressurized hydrogen gas condition showed fissuring and produced a reduction of the elongation in the plastic instability region due to hydrogen embrittlement, showing the effectiveness of the current in-situ SP test.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.298-307
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• 2018

Background: Subalpine ecosystems at high altitudes and latitudes are particularly sensitive to climate change. In South Korea, the prediction of the species richness of subalpine plant species under future climate change is not well studied. Thus, this study aims to assess the potential impact of climate change on species richness of subalpine plant species (14 species) in the 17 mountain national parks (MNPs) of South Korea under climate change scenarios' representative concentration pathways (RCP) 4.5 and RCP 8.5 using maximum entropy (MaxEnt) and Migclim for the years 2050 and 2070. Results: Altogether, 723 species occurrence points of 14 species and six selected variables were used in modeling. The models developed for all species showed excellent performance (AUC > 0.89 and TSS > 0.70). The results predicted a significant loss of species richness in all MNPs. Under RCP 4.5, the range of reduction was predicted to be 15.38-94.02% by 2050 and 21.42-96.64% by 2070. Similarly, under RCP 8.5, it will decline 15.38-97.9% by 2050 and 23.07-100% by 2070. The reduction was relatively high in the MNPs located in the central regions (Songnisan and Gyeryongsan), eastern region (Juwangsan), and southern regions (Mudeungsan, Wolchulsan, Hallasan, and Jirisan) compared to the northern and northeastern regions (Odaesan, Seoraksan, Chiaksan, and Taebaeksan). Conclusions: This result indicates that the MNPs at low altitudes and latitudes have a large effect on the climate change in subalpine plant species. This study suggested that subalpine species are highly threatened due to climate change and that immediate actions are required to conserve subalpine species and to minimize the effect of climate change.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.6
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• pp.773-781
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• 2018

In recent years, a study of power-line inspection using an unmanned aerial vehicle (UAV) has been actively conducted. However, relevant studies have been conducting power-line inspection with an UAV operated by manual control, and they have developed just power-line detection algorithm on aerial images. To overcome limitations of existing research, we propose a drone-based power-line tracking system in this paper. The main contributions of this paper are to operate developed system under configured environment and to develop a power-line detection algorithm in real-time. Developed system is composed of the power-line detection and the image-based tracking control. To detect a power-line in real-time, a region of interest (ROI) image is extracted. Furthermore, clustering algorithm is used in order to discriminate the power-line from background. Finally, the power-line is detected by using the Hough transform, and a center position and a tilt angle are estimated by using the Kalman filter to control a drone smoothly. We design a position controller and an attitude controller for image-based tracking control, and both controllers are designed based on the proportional-derivative (PD) control method. The interaction between the position controller and the attitude controller makes the drone track the power-line. Several experiments were carried out in environments where conditions are similar to actual environments, which demonstrates the superiority of the developed system.

• 대한공업교육학회지
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• v.36 no.2
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• pp.65-84
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• 2011

This Study was to conducted in order to suggest future direction for reorganization of Suwon ${\bigcirc}{\bigcirc}$ Women's High School as a vocational high school. The purpose of this Study was to provide suggestions for the Suwon ${\bigcirc}{\bigcirc}$ women's high school through workforce demand of electric-electronic-communication industry in Gyeonggi Province and SWOT Analysis. The findings of the study were as follows: First, the high school need to work out a educational strategy geared to workforce demand of region based electric-eElectronic-communication industry in Gyeonggi Province for students' employment. Second, the following two approaches are recommended for curriculum development to meet region based electric-eElectronic-communication industry in Gyeonggi Province for students' employment. (1) School curriculum development that is geared to a enterprise for students' employment. Demand of the enterprise is reflected when curriculum is developed under cooperation between school and enterprise. Specific knowledge, attitude and skills is emphasized to students according to demand of the enterprise. (2) school curriculum development that is geared to industry for students' employment. Demand of the electric-electronic-communication industry in Gyeonggi Province is reflected when curriculum is developed under cooperation between school and the electric-electronic-communication industry. Broader knowledge, attitude and skills is emphasized to students for the industry.

• The Journal of Fisheries Business Administration
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• v.30 no.2
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• pp.1-23
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• 1999

In the Northeast Asian region fisheries agreements of the past regarding high seas as an agreement area were transformed or new agreements were introduced in order to conform to the EEZ regime. However, the existing joint regulatory zone which “open” status is somewhat similar to the high sea not only disappear, but also two new systems were established. To begin with, parties of the agreement claimed their EEZs to be from the territorial sea baselines to the extent set forth, problem of the fishery access of the other party under the agreement is to be solved on the principle of reciprocity and on recognizing of the catch results achieved in the past. In regards to the overlapping zones like neutral zone of the East Sea of Korea(Sea of Japan) and neutral zone to the south of the Cheju Island, provisional measures zones in the Yellow Sea and in the East China Sea, and transitional zone of the Yellow Sea special fisheries management systems reflecting the legal character of the zone involved are applied. Moreover, as fisheries agreements defining open sea as an agreement zone are not able to conform to the EEZ regime, so new fisheries agreements must be taken out from old systems and conceptions, and must be understood and enforced from the new point view. Therefore, countermeasures needed to do so should be developed, and their basic structure is as follows. Firstly, the basic concept of the EEZ regime requires that the coastal states have sovereign rights on their sea zones' natural resources and bear responsibilities appropriate to their allowed jurisdiction. Each Northeast Asian state should adjust the structure of fishing industries and employ advanced fisheries management system, and should make efforts toward such issues of the state policy as increasing fishery resources and preserving ocean environment. Secondly, measures should be developed to solve the international fisheries disputes which are to occur under enforcement of the new fisheries agreements system. In regards to the acts of violation the fisheries laws in the foreign EEZ the principle of jail sentence prohibition is established by the UN Convention on the Law of the Sea, and every fisheries agreement reflects this principle. Therefore, the present question is to consider concrete measures to enable the easy release of the seamen, who violated fisheries laws slightly and well-intently, through establishment and management of the guarantee fund needed to make collateral reasonable. Thirdly, Korean-Russian and Russian-Japanese fisheries relations were formed on the basis of the EEZ regime, since 1992 and 1977 respectively, and are expected to maintain mutually beneficial cooperative character. As for Korean-Chinese-Japanese fisheries relations, the operational problems of overlapping zones, and problem of the permits for EEZ mutual access should be solved on the basis of the principle of reciprocity and equity rather than unilaterally from any side.

• Environmental and Resource Economics Review
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• v.17 no.3
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• pp.167-199
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• 2008

There are many successful cases in power interconnection among European and South American countries. However, that is not the case in Northeast Asian countries. Even though there will be a considerable benefit in power interconnection in Northeast Asian countries, there will be some difficulties due to various interest relationship and constraints among countries in Northeast Asia. GTMax(Generation and Transmission Maximization) Program is a very useful tool to analyze competitive electricity market and power interconnection developed by Argonne National Laboratory under the Department of Energy in the USA. This study tried to verify applicability and usefulness by GTMax model to domestic electric power system and power transfer from Russia Far East by power interconnection. When the power by importing from Russia is 2,000MW(around 2% of domestic installed capacity in 2017), there is no impact on domestic electricity market because of small power transfer. The power by importing should be large enough for achieving greater cost reduction by power interconnection. Besides, it would be better to supply power to Kyung-In region directly in reducing overall cost when the power by importing from Russia are sold at low price. In the case of interconnecting Young-Dong region, if it is not possible to upgrade transmission line with power transfer capabilities between Young-Dong and Kyung-In region, then the power by importing from Russia can replace the power produced in Jung-Bu region and the relative benefit of importing power can be reduced.

• Archives of design research
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• v.17 no.4
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• pp.15-26
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• 2004

After 19th century of Chosun Dynasty Gilsnagmunja-do such as longevity, good fortune, health, well-being which was explosively prevalent and Hyojemunja-do which was panoramically decorated with eight characters of filial piety, fraternal devotion, loyalty, trust, courtesy, commitment, integrity and humility for enlightment of the public under the name of political ideology are consistency or same origin in traditional concept of Orient. Therefore, in view of Western standard, they are showing an illustration and a photograph of characters in design. There are some differences in way of expressions. They were considerably popular not only in Chosun Dynasty but in China, Japan and Vietnam where belong to the cultural territory of chinese characters. Though, Hyojemunja-do which was built-up in the late period of Chosun Dynasty and developed fro chinese mode is a very peculiar iconography and mode of Chosun Dynasty. Hyojemunja-do is also classified from Chinese Nianhua designed for supply of Conficianism ethics or Folk Painting designed for practical use in chinese cultural territory. In the late period of 19th century, Hyojemunja-do which was re-built with creative modeling has been developed in peculiar mode in the province of Kyunggi, Kangwon(Kwan dong region), Kwanseo region, Jeju island and Namdo region by the diversified level of painters.