• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.3
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• pp.43-51
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• 2017

MANET consists of only wireless nodes having limited processing capability. It processes routing and data transmission through cooperation among each other. And it is exposed to many attack threats due to the dynamic topology by movement of nodes and multi-hop communication. Therefore, the reliability of transmitted data between nodes must be improved and security of integrity must be high. In this paper, we propose a method to increase the reliability of transmitted data by providing a secure cryptography protocol. The proposed method used a hierarchical structure to provide smooth cryptographic services. The cluster authentication node issues the cluster authentication key pair and unique key to the nodes. The nodes performs the encryption through two steps of encryption using cluster public key and block encryption using unique key. Because of this, the robustness against data forgery attacks was heightened. The superior performance of the proposed method can be confirmed through comparative experiment with the existing security routing method.

• Management Science and Financial Engineering
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• v.11 no.1
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• pp.63-78
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• 2005

Disassembly scheduling is the problem of determining the ordering and disassembly schedules of used or end-of-life products while satisfying the demand of their parts or components over a certain planning horizon. This paper considers the case of the assembly product structure for the cost-based objective of minimizing the sum of purchase, setup, inventory holding, and disassembly operation costs. To represent and solve the problem optimally, this paper presents an integer programming model, which is a reversed form of the multi-level lot sizing formulation. Computational experiments on an example derived from the literature and a number of randomly generated test problems are done and the results are reported.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2005.06a
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• pp.66-70
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• 2005

Microbiology research must be conducted in a fashion that assures the health and well being of the researcher and the safety of the community. This lecture raises awareness of biosafety issues and discusses how the interaction of the pathogen being studied, the person conducting the research, and the practices being used can be manipulated to assure safety. The characterization of pathogens into Risk Groups, how these relate to Biosafety Levels, and the personal practices and laboratory design criteria associated with each Biosafety Level are explained. The importance of preventing or containing aerosols, limiting opportunities for cross-contamination, and taking a flexible multi-component approach to biosafety are emphasized.

• Journal of Korean Society for Quality Management
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• v.33 no.1
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• pp.64-72
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• 2005

The ever increasing demand for enhanced competitiveness of engineered products requires "designing-in-quality" strategies that can effectively and efficiently incorporate concepts of uncertainty and quality into design. Multi-attribute utility function is commonly used to represent the decision-maker's preference on multiple design attributes under conditions of uncertainty and risk. One of the major issues in implementing this approach concerns the generation of appropriate utility function, especially in a complex engineering design environment. Typically, the decision maker's preference is revealed through lottery questions rather than being structured on the deductive reasoning to reflect the nonlinear tradeoffs among the attributes. The use of such intuitive procedures can lead to inexact preference information that may result in inaccuracy and rank reversal problems. This paper presents an alternative procedure based on the pair-wise comparisons between design alternatives towards a consistent preference presentation in assessing multiplicative utility function. The effectiveness of the overall procedures is tested with the aid of an injection-molding process design for a capacitor can and the results are discussed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.4
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• pp.1178-1191
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• 2014

The fault-tolerance routing problem is one of the most important issues in the application of the Internet of Things, and has been attracting growing research interests. In order to maintain the communication paths from source sensors to the macronodes, we present a hybrid routing scheme and model, in which alternate paths are created once the previous routing is broken. Then, we propose an improved efficient and intelligent fault-tolerance algorithm (IEIFTA) to provide the fast routing recovery and reconstruct the network topology for path failure in the Internet of Things. In the IEIFTA, mutation direction of the particle is determined by multi-swarm evolution equation, and its diversity is improved by the immune mechanism, which can improve the ability of global search and improve the converging rate of the algorithm. The simulation results indicate that the IEIFTA-based fault-tolerance algorithm outperforms the EARQ algorithm and the SPSOA algorithm due to its ability of fast routing recovery mechanism and prolonging the lifetime of the Internet of Things.

• Health Policy and Management
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• v.28 no.3
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• pp.320-326
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• 2018

As the United Nations announced Sustainable Development Goals (SDGs) in 2015, the world changed its development goals from focusing on efficiency to equity. As a result, in the health sector, universal health coverage (UHC) has become one of the main issues. This paper reviews and discusses on future direction and issue of official development assistance program for developing countries. Korea International Cooperation Agency under the Ministry of Foreign Affairs published on Korea International Cooperation Agency's mid-term health strategy 2016-2020 developed on participation program with stakeholder including governments, civil society partner organizations, and educational institutions. The SDGs expands non-communicable diseases, UHC, and global health security from the existing Millenium Development Goals health sector. Progress toward UHC underpins the achievement of all other targets under SDG Goal 3. Progress in reducing health inequality across the life course is drawing on overall data and from specific target. In order to achieve SDG 3, a multi-disciplinary approach, convergence between IT and u-health of this development, is desirable.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10d
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• pp.304-306
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• 2002

인터넷은 이미 생활의 한 부분이 되었으며 그 중에서 인터넷을 통한 전자상거래가 활발히 진행되고 있다. 그러나 현재의 전자상거래는 판매자가 일방적으로 제시하는 조건(가격)에 구매자는 단순히 거래를 하거나, 제시된 조건을 비교하여 보다 더 좋은 조건을 찾는 수준에 머물러 있으나 향후 전자상거래는 어느 한쪽의 일방적 제시가 아닌 서로의 이익을 최대화 할 수 있는 협상(negotiation)이 필수적이다. 본 논문은 시간제약 환경에서 다중속성을 이용한 협상 모델을 제안하며, 협상에서 고려되는 다중 속성들에 대해 각 에이전트들의 속성 값 변경과 서로의 제안 값 선택 전략을 제시하게 되고, 동일한 형태의 협상 메커니즘별로 두 에이전트간의 협상을 통해 제안한 협상 모델을 평가 한다.

• Journal of Theoretical and Applied Mechanics
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• v.2 no.1
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• pp.15-29
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• 1996

A fair portion of the dream to acquire the solutions to the Navier-Stokes equations has come true through the remarkable development of computers and solution algorithms in recent years. However, it is also true that there still remain serious hurdles in simulating general fluid flows. A few numerical trials to overcome the existing difficulties are introduced. The issues in numerical simulations of high-Reynolds-number flows, flows characterized by complex body geometry, and multi-phase flows, are scrutinized. The future of computational fluid dynamics as a promising tool for flow analyses is illuminated by this review.

• Journal of Communications and Networks
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• v.14 no.6
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• pp.710-718
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• 2012

The implementation of a common control channel is one of the most challenging issues in cognitive radio networks, since a fully reliable control channel cannot be created without reserving bandwidth specifically for this purpose. In this paper, we investigate a promising solution that exploits the ultra wide band (UWB) technology to let cognitive radio nodes discover each other and exchange control information for establishing a communication link. The contribution of this paper is threefold: (i) We define the communication protocol needed to let cognitive radio nodes discover each other and exchange control information for link set up, (ii) we overcome the gap in coverage, which typically exists between UWB and long-medium range technologies, by using multi-hop communication, (iii) we evaluate the performance of our approach by adopting an accurate channel model and show its benefits with respect to an in-band signaling solution.

• International Journal of High-Rise Buildings
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• v.9 no.3
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• pp.255-260
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• 2020

This research and technology development project is based on the concept and plan of Sumitomo Forestry Co., Ltd., and designed by Nikken Sekkei Ltd., and is aiming to realize 350 m supertall timber-framed buildings in urban areas by 2041, the 350 year anniversary of Sumitomo Forestry's founding(Fig. 1). By constructing office-based multi-use buildings which have 70 stories above ground with GFA of 455,000 ㎡, using a huge amount of timber of 185,000 ㎥, this project envisions to connect forests and cities, and to solve the problems in both of forests and cities. At the present stage, the main objective is to identify the issues related to wood, such as building structural systems, construction methods, materials used, and resource development, and to create a roadmap for future technologies to be researched and developed.