• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.123.1-123.1
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• 2016

마그네슘 및 마그네슘 합금은 차세대 경량 구조 재료로서 많은 각광을 받고 있지만, 상대적으로 높은 반응성과 낮은 부식저항성으로 인해 사용에 제한이 있어왔다. 최근 연구결과에 따르면, 상용으로 널리 쓰이는 AZ91 마그네슘합금에 Ca과 Y을 복합 첨가하였을 경우 마그네슘합금의 발화저항성을 크게 향상시키는 것으로 알려져 있어 마그네슘합금의 적용분야를 확대할 수 있을 것으로 많은 기대를 받고 있다. 그러나 이러한 합금이 실제적으로 적용되기 위해서는 반드시 내식성에 대한 평가와 연구가 수반되어야 하며, 이를 통해 부식거동에 대한 메커니즘을 규명함으로써 고내식 합금 개발을 위한 연구로 이어질 수 있도록 해야 한다. 따라서 본 연구에서는 기존의 AZ91D 합금과 Ca, Y이 복합 첨가된 modified AZ91D 합금 다이캐스트 주조재에 대하여 내식성을 평가 및 비교하고 부식 메커니즘을 규명하기 위한 미세조직 분석 및 부식거동 평가를 실시하였다. 본 연구결과에 따르면, AZ91D 합금 주조재에 Ca과 Y을 복합첨가한 합금은 발화저항성 뿐만 아니라 내식성도 크게 향상되는 것으로 나타났다. 이러한 내식성의 향상은 Ca과 Y의 첨가에 따른 Fe와 같은 불순물의 영향 감소 및 Ca과 Y이 포함된 이차상의 형성으로 인한 상과 기지간의 부식 전위의 차이 감소로 인한 미세 갈바닉 부식 발생의 감소 효과에 기인한 것으로 판단된다.

• Safety and Health at Work
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• v.7 no.2
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• pp.161-165
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• 2016

Background: Despite the declining trend of workplace accidents in Republic of Korea, its level is still quite high compared with that in other developed countries. Factors that are responsible for high workplace accidents have not been well documented in Republic of Korea. The main purpose of this paper is to estimate the effects of unions and health and safety committees on workplace accidents in Korean manufacturing firms. We also allow for the interactions between unions and health and safety committees in the analysis. The results obtained in this paper will not only contribute to the literature in this field, but might also be useful for employers and worker representatives who are trying to find an effective way to reduce workplace accidents. Methods: This paper utilizes the 2012 Occupational Safety and Health Trend Survey data, which is a unique data set providing information on workplace injuries and illness as well as other characteristics of participatory firms, representative of the manufacturing industry in Republic of Korea. Results: In estimating the effects of unions and health and safety committees, we build a negative binomial regression model in which the interactions between unions and health and safety committees are permissible in reducing workplace accidents. Conclusion: Health and safety committees were found to reduce the incidence of accidents whereas unionized establishments have higher incidence of accidents than nonunionized establishments. We also found that health and safety committees can more effectively reduce accidents in nonunionized establishments. By contrast, nonexclusive joint committees can more effectively reduce accidents in unionized establishments.

• Korean Journal of Plant Taxonomy
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• v.51 no.3
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• pp.181-191
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• 2021

Tulips are bulbous geophytes that have considerable commercial value worldwide. This genus primarily originated in the Tien Shan and Pamir-Alai mountain ranges, which surround the Ferghana Valley. The Ferghana Valley is home to five sections of the genus Tulipa L, represented by 23 taxa (22 species). However, there is a lack of detailed information about the distribution of Tulipa species in the natural geographic area of the Ferghana Valley. Therefore, to address this knowledge gap, we comprehensively investigated the spatial distribution of all Tulipa species in the valley. To assess the spatial distribution, the entire area was divided into 32 squares consisting of four latitudinal and eight longitudinal zones. The results showed that latitudinal zones B and C with 15 and 13 taxa, respectively, along with five longitudinal zones (A5, B3, B4, C2, and C3) with 5 to 10 taxa were hotspots for this genus. Additionally, the spatial distributions of the species in terms of the corresponding state borders, mountain ranges, endemism, and conservation issues were assessed. The findings of this study provide comprehensive information about the distribution of Tulipa species to assist with conservation initiatives ultimately to ensure the survival of various species.

• Journal of Astronomy and Space Sciences
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• v.31 no.1
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• pp.33-39
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• 2014

This paper describes an experimental approach to evaluate the effective doses of space radiations at high-altitude by combining the measured data from the Liulin-6K spectrometer loaded onto the air-borne RC-800 cockpit and the calculated data from CARI-6M code developed by FAA. In this paper, 15 exposed dose experiments for the flight missions at a high-altitude above 10 km and 3 experiments at a normal altitude below 4 km were executed over the Korean Peninsula in 2012. The results from the high-altitude flight measurements show a dramatic change in the exposed doses as the altitude increases. The effective dose levels (an average of $15.27{\mu}Sv$) of aircrew at the high-altitude are an order of magnitude larger than those (an average of $0.30{\mu}Sv$) of the normal altitude flight. The comparison was made between the measure dose levels and the calculated dose levels and those were similar each other. It indicates that the annual dose levels of the aircrew boarding RC-800 could be above 1 mSv. These results suggest that a proper procedure to manage the exposed dose of aircrew is required for ROK Air Force.

• Korean Journal of Veterinary Research
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• v.33 no.2
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• pp.321-326
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• 1993

Sixty eight wild rats were caught from Seoul, Kyonggi, Kangwon, Cholla, and Kyongsang provinces in Korea. All of them were confirmed in the same species, Rattus norvigicus. All of sera from wild rats were examined by indirect immunofluorescent test against Hantaan-related virus. Detection of anti-body to Hantaan-related virus were 4 out of 68 rats(5.9%), including 2 of 8(25.0%) rats in Kangwon and 2 of 20 rats(10.0%) in Kyongsang province. No difference of the sero-positive rates between sex of rats tested to Hantaan-related virus was recognized. According to age, four rats with antibodies(1:320~640) to Hantaan-related virus belonged one subadult, one young adult, one middle aged adult, and one old adult, respectively.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1999.06a
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• pp.159-164
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• 1999

Homogeneous but distinct visual objects having low-contrast boundaries are usually merged in most of the segmentation algorithms. To alleviate this problem, an efficient image segmentation algorithm based on a bottom-up approach is proposed by using spatial domain information only. For initial image segmentation, we adopt an efficient marker extraction algorithm conforming to the human visual system. Then, two region-merging algorithms are successively applied so that homogeneous visual objects can be represented as simple as possible without destroying low-contrast real boundaries among them. The resultant segmentation describes homogeneous visual objects with few regions while preserving semantic object shapes well. Finally, a size-based region decision procedure may be applied to represent complex visual objects simpler, if their precise semantic contents are not necessary. Experimental results show that the proposed image segmentation algorithm represents homogeneous visual objects with a few regions and describes complex visual objects with a marginal number of regions with well-preserved semantic object shapes.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.123-126
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• 2010

This paper attempts to conceptually examine the factors affecting the growth potential of WiBro in the Korean communication market. The results of the paper implies that the WiBro service operators' business intentions mainly affect the its diffusion negatively and the convergence service combining WiBro with other heterogeneous service including Telematics services might enable WiBro to successfully grow compensating the current limitation of WiBro.

• Journal of the Korean earth science society
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• v.43 no.4
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• pp.481-489
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• 2022

Various types of karst topographies are found worldwide. Owing to their global distribution, karst areas have been extensively studied by scientists who investigate new discoveries by linking the characteristics of karst topographies with their own research fields. However, there have been only a few studies on karsts in the Republic of Korea, and little research exists on their hydrogeology. Fragmentary studies have been conducted on the hydrochemical characteristics of groundwater in limestone areas, the causes of high arsenic concentrations in groundwater, and the hydraulic conductivity of limestone areas. Research on hydrogeological characterization and flow mechanisms in these areas has only began recently. Identification and the proper management of available groundwater resources in karst (limestone) areas is essential as their unique geological characteristics render it difficult to construct reservoirs or dams at appropriate scales. We have reviewed prior work on karsts in the Republic of Korea to provide information that supports water resource security in the karst areas, to improve the understanding of the equitable use of water resources, and to identify the best management practices for groundwater resource resilience improvement.

• Health Policy and Management
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• v.33 no.2
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• pp.214-222
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• 2023

Refugees who are persecuted can apply for refugee recognition in the Republic of Korea in accordance with the Refugee Convention and the Refugee Act. They can do so either at the port of entry or during their stay in Korea. After undergoing screening, individuals may be recognized and protected under different categories, such as recognized refugees, humanitarian status holders, refugee applicants, and refugees seeking resettlement. Recognized refugees are entitled to the same social benefits and basic livelihood guarantees as Korean nationals. Humanitarian status holders and refugee applicants may receive support such as minimum living expenses, housing facilities, medical care, and education. In the medical field, refugees and their unmarried minor children are eligible for medical support through the "Medical Service Support Project for Marginalized Populations, Including Foreign Workers." This support is in addition to the national healthcare coverage and medical benefits provided by the government. However, there are pressing concerns regarding the inadequate budget allocated to this project and the excessive cost burden placed on participating medical institutions. It is crucial to secure additional funding and implement administrative improvements. Furthermore, it is essential to develop medical support measures that ensure the minimum right to health for individuals who choose not to undergo the refugee recognition process at the port of entry.

• Journal of Arbitration Studies
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• v.20 no.1
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• pp.133-167
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• 2010

The enforcement of commercial arbitration awards in the People's Republic of China is one the controversial obstacles faced by foreign investors in China. The foreign investor will fail to enforce the arbitration award, if the Chinese court refuses the enforcement in China, even if the arbitration tribunal rules the award in favor of foreign investor who is in dispute with Chinese partners. In Korea, we have not many researches in the enforcement of foreign related awards and awards ruled by other jurisdiction. In recent times, Professor Kyung-Ja Cha(2005) and Professor Sun-Jeong Kim(2008) analyzed the enforcement of arbitration awards in China. Professor Kyung-Ja Cha(2005) reports the details of the enforcement statistics of CIETAC during 1990s. Professor Sun-Jeong Kim(2008) analyzed the obstacles of the enforcement of foreign related awards in China. This paper extends their researches in the field of the enforcement of arbitration awards in China. First, this paper extends Professor Kyung-Ja Cha(2005)'s study by introducing the Chinese enforcement situation during the period of 2000-2007. Second, this paper extends Professor Sunjung Kim(2008) emphasizes the local protectionism and the weakness of judiciary as key factors of obstacles to enforce the foreign related awards in People's Republic of China. This paper, additionally, highlights the role of the Guanxi and the antagonism of court toward arbitration institution to enforce the foreign related awards in People's Republic of China. Third, this study provides the recent developments of Supreme People's Court(SPC)'s rules to narrow down the gap between the practices of international arbitration and those of People's Republic of China. The Implications of this study are as follows. First, it is desirable for foreign investors to appoint the CIETAC or BAC as the arbitration commission in China. Second, the local competent attorney is the best choice to solve the respondent's insolvency in China. Third, foreign investors is required to monitor the provisions on the electronic instruments such as EDI and Email in Chinese law.