• Magazine of RCR
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• v.16 no.3
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• pp.39-44
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• 2021

• Nuclear Engineering and Technology
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• v.45 no.3
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• pp.393-400
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• 2013

Concrete undergoing early frost damage in cold weather will experience significant loss of not only strength, but also of permeability and durability. Accordingly, concrete codes like ACI-306R prescribe a minimum compressive strength and duration of curing to prevent frost damage at an early age and secure the quality of concrete. Such minimum compressive strength and duration of curing are mostly defined based on the strength development of concrete. However, concrete subjected to frost damage at early age may not show a consistent relationship between its strength and durability. Especially, since durability of concrete is of utmost importance in nuclear power plant structures, this relationship should be imperatively clarified. Therefore, this study verifies the feasibility of the minimum compressive strength specified in the codes like ACI-306R by evaluating the strength development and the durability preventing the frost damage of early age concrete for nuclear power plant. The results indicate that the value of 5 MPa specified by the concrete standards like ACI-306R as the minimum compressive strength to prevent the early frost damage is reasonable in terms of the strength development, but seems to be inappropriate in the viewpoint of the resistance to chloride ion penetration and freeze-thaw. Consequently, it is recommended to propose a minimum compressive strength preventing early frost damage in terms of not only the strength development, but also in terms of the durability to secure the quality of concrete for nuclear power plants in cold climates.

• Korean Journal of Organic Agriculture
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• v.11 no.3
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• pp.37-53
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• 2003

The purpose of this study is to analyze policies on environmental-friendly agriculture(EFA) and find out some implications. As we know well, EFA contributes environmental substantiality by using organic production methods and provides consumers with a secure, safe nutritious food supply. As consumption of environmental-friendly agricultural products increasing, policies on EFA began in the 1990s and it has been generally expanded in Korea. The strategies for sustainable EFA aim to promote harmony among human beings and between humanity and nature require. In addition, support to develop marketing activities, regionalization, and political support must be further developed.

• Journal of the Korean Graphic Arts Communication Society
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• v.20 no.1
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• pp.1-15
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• 2002

The objective of this study was carried out to investigate the study of printing presses and material industry for foreign countries market development(The point of Russia market) by examine the status of printing industry in domestic and russian. The results obtained from this study were the development and insurance of technical in printing industry market seemed to have secure a technical area in 21th century owing to have a exercise influence over about itself and material industry area.

• The Korean Journal of Ecology
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• v.23 no.2
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• pp.75-81
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• 2000

This paper was prepared to have an overview of the Long-Term Ecological Research (LTER ) activities in Korea in order to facilitate further development of Korea LTER Network in the coming 21th century. After the background for the development of the Korea LTER network was reviewed, the network activities of Korea as well as of the world were introduced for sound management and conservation of ecosystems, which can be ultimately carried out by the long-term ecological researches whose results can secure comparability in the dimension of time and space.

• Electronics and Telecommunications Trends
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• v.37 no.4
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• pp.11-18
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• 2022

Sharing vehicle data among the companies within a car ecosystem can improve driving experience, increase driver comfort, contribute to social goals such as improving road safety and lowering fuel consumption. Furthermore, by participating in the ecosystem, companies can secure long-term and sustainable new revenue-generating opportunities. In this paper, we will examine the bottleneck and success factors of data sharing, as well as the technological solutions that urgently require development for car data sharing.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.225-226
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• 2022

In order to secure the practicality of services using drones, improve on-site operability, and improve the convenience of aircraft maintenance, it is necessary to develop a drone station that can be safely stored while ensuring charging performance. Therefore, a total seven points of improvement were derived through laboratory experiments after the development of the first prototype, and an improved second prototype will be developed in the future based on the preceding processes.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.291-294
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• 2007

Countries in the world are setting up policies to implement anti-global warning measures to actively cope with the Agreement on Climate Change. Rising problems related to energy and environment prompted research and development efforts to highly efficient electric instrument and environmentally friendly products to secure resources and save energy Korea's high dependency on imported energy and its lack in natural resources make it urgently necessary to develop energy efficient instrument and equipment that can save energy. Every household now uses a transformer, which is very important instrument among others. A variety of technologies to manufacture transformers are currently used along with efforts to develop new materials. Development nit of high efficient transformers is called for by the time and has direct economic impact on suppliers and consumers. In addition, it is desirable to install a transformer that is trustworthy, secure, low on loss, anti-incident capable, small, anti-flammable, environmentally friendly, cost-efficient high-frequency resistant and easy for maintenance. To do this, it is necessary to look deeper into a highly efficient transformer that can save energy. This paper will discuss the types and characteristics of various transformers and propose ways to save energy and raise efficiency tv analyzing a environmentally friendly amorphous transformer.

• International Commerce and Information Review
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• v.9 no.1
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• pp.355-379
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• 2007

With the effectuation of United Nations Framework Convention on Climate Change(UNFCCC) and Kyoto Protocol in 2005, ever growing concern on the importance of overseas forestation is diffusing worldwide. However, fierce international competition to secure overseas forestation sites, inherent uncertainty in UNFCCC or overseas forestation projects, and imbalances among policies on overseas natural resources development make it difficult to realize Korean long-term overseas forestation objective to secure 1 million ha by 2050. In view of necessity of overseas forestation projects for sustainable forest management and securing sinks of carbon to mitigate climate change, various efforts to reform current Korean overseas forestation systems are required. This study suggests several alternatives to improve current Korean overseas forestation systems including expanding financial support for overseas forestation projects, cultivating overseas forestation experts, establishing official organization for overseas forestation, constructing effective support system for overseas forestation projects, fostering international cooperation in the field of forest resources, and so on. Many theoretical, empirical or policy-oriented studies on the influences of UNFCCC and countermeasures on it in various Korean industries should follow this study.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.2
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• pp.479-487
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• 2015

According to IT development, smart home services is providing remote service, monitoring service and other various services through smart home devices based on network. But, smart home environment exists security threats such as data falsification, illegal authentication and invasion of privacy through a malicious device. Smart home is studying to prevent these security threats, but the studies of smart home environment security are still in early stage of development and the studies of group key management method is lacking in smart home. In this paper, we propose the group key management method for secure device in smart home.