• 한국결정성장학회지
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• 제3권1호
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• pp.75-84
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• 1993

황산동 수용액으로부터 치환법을 이용하여 흑연입자에 동을 코팅시켰다. 흑연입자표면에 연속적이고 균질하게 동이 코팅된 최적조건을 확립하기 위하여 동이온 농도, 교반속도, 반응시간 및 반응온도 등의 영향을 조사하였다. 이때 동 코팅반응의 활성화에너지는 3.59kcal/mole이었다.

• Journal of Communications and Networks
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• 제11권4호
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• pp.406-415
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• 2009

In this work, we consider performance modeling of a wireless sensor network with a time division multiple access (TDMA) media access protocol with slot reuse. It is assumed that all the nodes are peers of each other and they have two modes of operation, active and sleep modes. We model the sensor network as a Jackson network with unreliable nodes with on and off states. Active and sleep modes of sensor nodes are modeled with on and off states of unreliable nodes. We determine the joint distribution of the sensor node queue lengths in the network. From this result, we derive the probability distribution of the number of active nodes and blocking probability of node activation. Then, we present the mean packet delay, average sleep period of a node and the network throughput. We present numerical results as well as simulation results to verify the analysis. Finally, we discuss how the derived results may be used in the design of sensor networks.

• 한국항만경제학회지
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• 제19권2호
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• pp.69-85
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• 2003

The current legislation of the Port Authority which empowers the central government to control finance, personnel management, business of the Port Authority should be amended to allow the Port Authority to exercise its authority over port management and operation by gaining authority from the central government. In addition, to enhance Busan port's competitiveness and for a successive activation of the Susan Port Authority, it is necessary for the BPA to develop its new business and for the Busan Metropolitan City to establish both the department of Port Logistics and relevant regulations. The central government should also support and cooperate with the BPA rather than controlling the Authority.

• Macromolecular Research
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• 제14권3호
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• pp.354-358
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• 2006

Polybutadiene (BR) was pyrolyzed at $540-860^{\circ}C$ and the effect of pyrolysis temperature on variations in the relative abundance of the major pyrolysis products (C4-, C5-, C6-, C7-, and C8-species) was investigated. Formation of the C4-, C5-, C6-, and C7-species competed with that of the C8-species. Relative intensity of the C8-species decreased with increasing pyrolysis temperature, while that of the C5-, C6-, and C7-species increased. Pyrolysis paths were became more complicated with increasing pyrolysis temperature. We suggested the operation of double bond migration and succeeding rearrangements for the formation of the C5- and C7-species and various rearrangements, including a double bond, for the formation of the C6-species at high temperature. The activation energies for the pyrolysis product ratios of(C5+C6+C7)/C4 and C8/C4 were used to explain the competition reactions to form the pyrolysis products.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2007년도 한국컴퓨터종합학술대회논문집 Vol.34 No.1 (B)
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• pp.396-400
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• 2007

우리나라의 게임산업은 지속적으로 성장해왔지만, 플랫폼별 게임산업규모를 살펴보면 PC기반 온라인 게임에 크게 치중되어있는 모습이다. 반면 세계시장은 비디오게임시장이 온라인게임시장보다 약 5배가량 더 크다. 최근 차세대 비디오게임기의 출시, 콘솔제조사들의 콘솔의 온라인기능 강화, 해외 게임개발사의 온라인 게임 개발 러쉬, 크로스플랫폼기반의 게임개발 등 게임시장의 이슈를 살펴보면 플랫폼의 구분은 무의미해지고 점차 온라인을 통한 네트워크 게임이 활발해질 전망이다. 이러한 시장트렌드에 맞춰 온라인게임 강국으로서의 노하우를 콘솔게임에 접목해보는 것은 온라인게임산업에 있어서 제2의 도약을 준비하고 플랫폼별 게임산업간의 불균형을 해소할 수 있는 기회가 될 수 있다. 본 논문에서는 온라인게임의 성장에 가장 큰 역할을 하고 있는 게임유통업계에서 활용할 수 있는 콘솔게임 운영관리시스템의 설계 및 구현 사례를 통해 콘솔게임의 멀티플레이 활성화 방안을 제시한다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 추계학술대회 논문집
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• pp.193-195
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• 2008

As arising the cost and decreasing of gasoline and fossil fuel, renewable energy sources such as photovoltaics, wind and fuel cell have been interested. Among of them, PEM fuel cells are good energy sources to provide reliable power at steady state regardless of weather, time of day and location as long as the fuel and air are supplied, but they cannot respond to electrical load transients as fast as desired. This is mainly due to their slow internal electrochemical and thermodynamic responses. Therefore, to use the fuel cells with high efficiency, this paper finds characteristic curve and understand operation of PEMFC based on three theoretical approaches such as activation, ohmic and concentration and make the model using MATLAB. That result was compared with real system to certify.

• 한국식품영양학회지
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• 제12권4호
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• pp.358-363
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• 1999

This study was conducted to evaluate the extraction methods for the determination of antioxidants in soybean oil. Recovery rates of various antioxidants in soybean oil showed similar rates as 80.4~102.1% by solvent/solvent extraction method and 89.9~106.4% by sweep co-distillation method except 46.6~61.2% of PG at corresponding spiked concentractions. The maximun recovery rates of antioxidnts were obtained when extraction time and extraction temperature used in UNITREX were 20min and 21$0^{\circ}C$ respectively. In the recovery rates with the activation of florisil when 2% ofwater was added to florisil the highest recovery rates for TBHQ, BHA, BHT were obtained by sweep co-distillation met-hod. Therefore sweep co-distillation method showed less solvent simple operation and high recovery rate compared with solvent/solvent extraction method.

• Journal of Ship and Ocean Technology
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• 제7권1호
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• pp.19-28
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• 2003

The systematic results of anti-rolling tanks tests obtained by bench tester and roll test in towing tank have been examined. The effects on the oscillating period of fluid transfer through the duct of U-tube tank due to damper plates and the effects on roll damping moment of the tank due to swash plates are alto evaluated from the results. A simple control algorithm for a forced fluid transfer in U-tube tanks if devised to active operation of the tank by air blower. The active performances of the tank are confirmed very effective through the tank tests carried out in the irregular waves.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1340-1345
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• 2009

Ministry of Land, Transportation and Maritime Affairs has implemented Construction CALS project for improving informationization level of construction industry and for making construction production system efficient. Although an importance of evaluation on level and performance of construction informationziation projects has been emerged, Construction CALS hasn't been evaluated so far. In this study, the performance indicators of construction CALS as the most important base in creating a performance management system were deduced. For this aim, this study reviewed the former researches on system construction for managing performance, analyzed current status of Construction CALS, arranged the relationship between upper strategies and ISP, developed pools of performance indicators, and this study followed IT BSC methodology. As a result, this study developed performance indicators of Construction CALS through four strategies such as globalization and activation of Construction CALS standards, research & development for reaching to international level in construction informationization technology, stabilization of system operation and distribution by publicizing Construction CALS and improving its functions, and policy implementation for managing and coordinating Construction CALS projects. These indicators will be applied to build a system of performance management.

• Nuclear Engineering and Technology
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• 제56권4호
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• pp.1250-1253
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• 2024

Activity measurement of the primary circuit water of fission reactors is one method that can provide early detection of a damaged fuel assembly in the reactor core. This is an important aspect in the safe operation of the reactor and for radiation protection of staff. Radionuclides in the primary circuit water are produced by the activation of stable nuclides and the fission of fissile nuclides, mainly the isotope ²³⁵U. In the LVR-15 research reactor, measurement of the activity of the primary circuit water has been regularly undertaken since 1996. A water sample is taken from the primary circuit every week and the activities are measured four days later using gamma spectrometry. The results of these long-term measurements from 1996 to 2022 are presented. The activity time dependences of the individual radionuclides are discussed in relation to fuel assembly damage and for events connected to contamination of the water by objects inserted into the primary circuit during experiments carried out near the reactor core.