• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2202-2209
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• 2009

Joint paths are induced mathematically for many kinds of joint pattern between master- and sub-pipes. By compensating them with root gap of welds and kerf width, real cutting paths are determined. Their NC codes are generated, and the paths generated by NC code are verified by a ghost function. A beveling is implemented through tilting a torch in the A- and B-axis direction for 8 sections in the chuck rotation of C-axis. The effective CAM program was developed specially for 6-axis CNC pipe coasters which cut a master or sub- pipe along the cutting path and simultaneously fulfill a beveling process.

• ETRI Journal
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• v.36 no.1
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• pp.183-186
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• 2014

In this letter, we consider a cooperation system with multiple untrusted relays (URs). To keep the transmitted information confidential, we obtain joint channel characteristics (JCCs) through combining the channels from the source to the destination. Then, in the null space of the JCCs, jammers construct artificial noise to confuse URs when the source node broadcasts its data. Through a distributed implementation algorithm, the weight of each node can be obtained from its own channel state information. Simulation results show that high-level security of the system can be achieved when internal and external eavesdroppers coexist.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3271-3276
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• 2010

Preparing to reclaim the wartime operational control of South Korea's armed forces, Korea Military have to embattle the right capability in relation to conduct of the war. Although Korea Military are operating Joint Exercise Simulation Training System, they are having a lot of difficulties because of interoperability according to a joint exercise with USA military and pursue an independent korea military models. Therefore this study analyzes technical problems and proposes some measures to establish Exercise Simulation System out of regard for South Korea's self defense.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.2
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• pp.348-353
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• 2007

This paper presents design specifications and characteristics of bridge expansion joints to develop new type-joints in fiber reinforced polymer decks. Based on properties of the fiber reinforced polymer decks and fundamental process to calculate their expansion length, new expansion joints fur fiber reinforced polymer decks on typical steel or concrete girder are developed and proposed.

• Proceedings of the Korea Contents Association Conference
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• 2004.05a
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• pp.261-267
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• 2004

In undeniable digital signature scheme, the signature can not be verified without the signer's cooperation. The undeniable signature scheme can be used to computerize many applications which can not be done by a conventional digital signature scheme. In this study, we propose the undeniable digital multi-signature scheme which requires many signers and designated verifier. The multi-signature can be verified only in cooperation with all signers. The proposed scheme satisfies undeniable property and it is secure against active attacks such as modification and denial of the multi-signature by signers. We also discuss practical applications such as joint copyright protection on digital contents.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.4
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• pp.795-802
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• 2007

In the future combat fields, US department of defense (DoD) pursuits the enhancement of the synergy effects of the force through the networking. In specially, the US army force has been emphasized the information superiority for the knowledge superiority and decision superiority of the collaboration force in the Joint Vision 2020, when the operations is performed in the battle fields. In this case study, we are reviewed about the concept of network centric operation and operation case in the centering around the US and analyzed the quantitative distance and effect, performance of communication relay about the distance of mission operation.

• Electronics and Telecommunications Trends
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• v.38 no.4
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• pp.25-35
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• 2023

As the global semiconductor supply chain falters, major countries are pushing to increase their self-sufficiency in semiconductors. In accordance with these global changes, R&D cooperation is evolving in the semiconductor industry. Previously, as for the case of Interuniversity Microelectronics Center (IMEC) in Europe, many cooperation initiatives were established regardless of nationality for improving productivity through measures such as reducing the time and cost required for joint research. Recently, however, cooperation aimed at strengthening one's own industry has been prominent, such as that led by Taiwan Semiconductor Research Institute (TSRI) and the United States National Semiconductor Technology Center (NSTC). Hence, the Korean semiconductor industry also needs to respond. Internally, technology localization should be promoted by strengthening the foundation for domestic R&D cooperation, while externally, it should expand close cooperation with companies from countries leading the semiconductor industry, such as the United States, Europe, and Japan.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.2255-2262
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• 2015

Recent study about near-surface is proposed to overcome non-economic of underground railway and to reduce people's complaints of ground elevated railway. In this report, precast modular structure system replacing temporary facilities is applied to ensure the construction ability and economic feasibility. To verify the performance of connection joint between permanent structural wall and upper slab, loading test is carried out. As a result of the test, wall replacing temporary structure to slab connection is possible to transfer bending moment. By 30% increase of bending resistant performance for connection joint using coupler, coupler connection joint is more advantageous to resist bending moment compared to channel connection.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.138-142
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• 2018

This study used HILS to test an expansion joint, which is vulnerable to the water hammer effect. The operation data for the HIL simulator was the length rate of the expansion joint by the water hammer, which was used for life prediction based on the vibration durability. For the vibration durability test, the internal pressure of the expansion joint was assumed to be a factor of the durability life, and the lifetime prediction model equation was obtained by curve fitting the lifetime data at each pressure. During the test, the major failure modes of crack and water leakage occurred on the surface of the bellows part. The lifetime prediction model typically follows an inverse power law model. The pressure is a stress factor, and the model is effective in only a specific environment. Therefore, another stress factor such as temperature will be added and considered for a mixed lifetime prediction model in the future.

• Journal of the Society of Disaster Information
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• v.4 no.1
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• pp.154-174
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• 2008

Korean public power isn't currently performing its duties of crime prevention or public security services as effectively as the people expect from it due to excessive work load, insufficient budget, and equipment or work force problems, although it should protect the people from increasing crimes. The mutual cooperation between the police and the private security firms can' t be enhanced unless both parties are involved. Above all, the private security companies should secure superior security personnel and provide them with systematic education and training to improve their qualities. The police should also make an effort. In order to foster the private security firms soundly, the police should improve the system if necessary, and establish, guide and monitor the department wholly responsible for the private security affair. Both parties also should deal with crimes systematically by exchanging information for crime prevention, having informal meetings and introducing a joint patrol system. In order to cope with crimes threatening the livelihood of the people in our society, the public and private securities' mutual cooperation plans should be formulated. For this purpose to be achieved, the private security firms and the police should understand each other and bilateral efforts should be made. If both parties understand each other and make an effort, the relationship between them will be improved greatly and developmental plans for preventing crimes can be made.