• 대한기계학회논문집B
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• 제22권8호
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• pp.1052-1063
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• 1998

The performance database of small-sized centrifugal compressors is needed for the design of high performance machines and also for the verification of design tools and analysis software. An impeller is designed, manufactured and tested. The effects of several parameters on the evaluation of performance are investigated and the performance test of parallel diffuser is also carried out. The proper estimation of static pressure, total temperature and blockage at the impeller exit is important for performance evaluation. 4 method in cooperation with 3-D calculation is suggested. The measured performances are in a good agreement with the predicted results. However, there are some discrepancies in efficiency.

• 항공우주정책ㆍ법학회지
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• 제25권2호
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• pp.231-247
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• 2010

This paper starts with a brief overview of the history of the European Space Agency and recalls some of its main features. Next, the gradual process of cooperation between ESA and the EU is outlined, leading to the creation of the Framework Agreement in 2004 and the adoption of the European Space Policy in 2007. The entry into force of the Lisbon Treaty in 2009 codified the space competence of the EU, and its implications are addressed. Lastly, some attention is paid to the issue of space security in Europe, through ESA's new SSA programme adopted in 2008, and to the relevance of the EU Council initiative for a Code of Conduct for Outer Space Activities in 2008. The paper ends with some conclusions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전력기술부문
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• pp.273-275
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• 2008

In Korea, over 97% of local energy demand is imported from other countries. And we have to lift the energy independence level up to 5% with replacement energy(renewable energy) such as solar, wind..etc. by 2011 according to the energy agreement made in Kyoto Protocol. So, we proposed some opinions such as the better improvement of solar thermal industry the people' view, cooperation among industry/university/research institutes, remote control/maintenance and government's legislature and supporting system etc.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2009년도 추계학술발표논문집
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• pp.562-565
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• 2009

이종 망 환경에서 멀티미디어 서비스의 QoS를 보장하는 것은 3GE 시스템 개발을 위한 중요한 이슈이다. 이동 단말기가 이종 망간의 이동 시 끊임없는 서비스(seamless service)를 지원하기 위해서는 종단간(end-to-end) 협상 정보에 근거하여 사용자의 QoS를 보장할 수 있는 QoS 운영 구조(QoS management structure)를 제공해야 한다. 본 논문에서는 SLA(Service Level Agreement)에 기반한 종단간 QoS 제어 방안을 제시한다. 이를 위하여, QoS 지원을 위한 SLA 제어 구조 및 알고리즘을 제안하고, 시뮬레이션을 통하여 평균 지연과 패킷 손실률을 평가한다. 제안된 방식을 적용한 시스템이 기존의 망보다 더 좋은 성능을 보인다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.249-251
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• 2011

International energy agency(IEA) consisted of OECD countries deals with international energy problems. IEA/Wind ExCo is an execution committee under IEA for the implementing agreement for co-operation in the research, development and deployment of wind energy systems. Currently 22 countries participate the committee and 11 research tasks are in progress. 11 tasks are base technology information exchange, wind energy in cold climates, offshore wind energy technology deployment, integration of wind and hydropower systems, power systems with large amounts of wind power, cost of wind energy, labelling small wind turbines, social acceptance of wind energy projects, MexNext aerodynamics and comparison of dynamic computer codes and models, offshore wind energy and wakebench. At the presentation, activities of major wind energy countries and IEA/Wind ExCo and research tasks are introduced.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2011년도 춘계학술논문집 1부
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• pp.45-48
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• 2011

본 논문에서는 RFID 보다 뛰어난 보안 서비스를 제공하는 NFC의 세 가지 운영모드인 Reader/Writer 모드, Card Emulation 모드, Peer-to-Peer 모드를 살펴보고, NFC 보안 기술인 NFC-SEC에서 제공하는 Key Agreement, Key Confirmation, SSE, SCH를 분석한다. 접속 과정의 경량화를 위해서 마스터 키를 갱신하여 유지하는 프로토콜을 제안하고, 제안 프로토콜을 분석 및 평가한다.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2010년도 춘계학술발표논문집 2부
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• pp.961-964
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• 2010

A semi-empirical fluctuation term is presented to improve a classical equation of state (EOS) for volumetric properties in the critical region. The term is based on the two assumptions: (1) The Helmholtz energy is individually divided into classical and long-range density fluctuation contribution (2) All molecules form cluster near the critical region due to long-range density fluctuation. To formulate such molecular cluster, we extended the Veytsman statistics originally developed for the cluster due to hydrogen bonding. The probability function in the statistics is modified to represent the characteristics of long-range density fluctuation vanishing far from critical region. The proposed fluctuation contribution was incorporated into the Sanchez-Lacombe EOS and the combined model with 6 adjustable parameters has been tested against experimental VLE data. The combined model is found to well represent flatten critical isotherm for methane and top of the coexistence curve for the tested components. The prediction results for caloric data are in good agreement with the experimental data.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 B
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• pp.669-671
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• 1998

Engine immobilizer is the automobile security system which disables the engine if the secrete code in the transponder embedded in the key knob is not in agreement with the code in ECU of the car. There are many types of immobilizer systems, however, the encryption transponder type system is the most secure system due to the code verification method using an encryption method. As an example of the industry-university cooperation, the software development in the system is introduced in this paper.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.762-764
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• 2003

In Korea, over 97% of local energy demand is imported from other countries. And we have to lift the energy independence level up to 5% with replacement energy (renewable energy) such as solar, small hydropower, etc. by 2011 according to the energy agreement made in Kyoto Protocol. So, we proposed some opinions such as the better improvement of small hydropower industry the people' view, cooperation among industry/university/research institutes, remote control/maintenance and goverment's legislature and supporting system etc.

• 한국항공운항학회지
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• 제27권4호
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• pp.83-95
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• 2019

In order to promote the domestic aircraft manufacturing industry, this study analyzed the limitations of the preceding study on the WTO dispute concerning civil aircraft by summarizing the latest developments and issues in the mid-range aircraft dispute between Brazil and Canada and the large civil aircraft dispute between the United States and the EU. Based on the results of the study, we should look closely at WTO regulations and existing cases of disputes to find maximum support measures, and we believe that in order to stimulate the domestic aircraft manufacturing industry, we should refrain from publicly specifying support measures in the data, such as laws and policies, utilize the WTO SCM Agreement exceptions, and strengthen links with international cooperation and other industries.