• Strategy21
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• 통권45호
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• pp.116-147
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• 2019

한국은 지형적으로 반도국가이며 국제정치적으로는 중견국의 위상을 갖고 있다. 이런 유리한 조건에도 불구하고 아직도 대륙지향적 사고에 갇혀 있으며 이는 정교한 해양전략의 탄생을 지체시키는 걸림돌로 작용하고 있다. 이를 극복하기 위해 '바다의 유형'과 '위상'이라는 두 가지 변수를 이용하여 '해양접근전략(the Maritime Access Strategy)'을 제시한다. 나아가 전략을 구성하는 3대 요소-목표, 방법, 수단-을 이용하여 해양접근전략의 정교화를 시도한다. 목표 차원에서는 국가적 차원의 목표를 지원하도록 동기화가 필요하다는 전제에 주목한다. 더불어 다양한 행위자와 상대해야 함을 고려하여 억지(Deterrence), 관여(Engagement), 견제(Check)라는 소목표를 제시한다. 방법 차원에서는 기능적 균형화 작전방안을, 수단 차원에서는 기능적 균형전력을 제시한다. 해양접근전략은 다양한 바다에서 접근강도의 유연성을 갖고 맞춤형으로 다가가는 역동적 메커니즘을 품고 있다.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.283-287
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• 2003

A new method to miniaturize ${\lambda}/4$ transmission line of power divider is proposed. The method utilizes simple combination of the shorted coupled-line pair instead of the transmission line with very high impedance and shunt lumped capacitors. The length of ${\lambda}/4$ transmission line of power divider is about 16% over the conventional power divider at 1 GHz.

• 한국항해항만학회지
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• 제27권1호
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• pp.81-86
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• 2003

본 논문은 초고주파 전력증폭기용 LDMOS(Lateral double-diffused MOS) MRF-21060소자의 게이트 바이어스 전압을 조절하여 온도 변화에 따른 드레인(Drain) 전류의 변화를 억제하기 위한 PNP 트랜지스터를 사용하여 능도 바이어스 회로 구현하였다. MRF-21060을 구동하기 위한 방법으로서는 AH1과 평형증폭기인 A11을 사용하여 구동 증폭단을 설계.제작하였다. 제작된 5W 초고주파 전력증폭기는 0~$60^{\circ}C$까지의 온도변화에 대하여 소모전류 변화량이 수동 바이어스 회로에서 0.5A로 높은 반면, 능동 바이어스 회로에서는 0.1A이하의 우수한 특성을 얻었다. 전력증폭기는 2.11~2.17GHz주파수 대역에서 32dB 이상의 이득과 $\pm$0.09dB이하의 이득 평탄도가 나타났으며, -19dB이하의 입.출력 반사손실을 가진다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 F
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• pp.1981-1983
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• 1998

The principle of the MHD generation is based on Faraday's law of induction that a eletromotive force(u ${\times}$ B) is generated when the working gas of velocity u flows a channel in which magnetic field of strength(B) exists. In MHD power generation system, enthalpy of the working gas is converted to electric power directly through expansion in generator channel. It means that electric power can be generated without moving mechanical linkage such as turbine blades. There are two types in the MHD generator; linear type Faraday and disk type hall generator. Disk type hall generator is the main target of this paper. Isentropic efficiency and enthalpy extraction rate of disk type shock tube driven hall generator is discussed here.

• Strategy21
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• 통권43호
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• pp.57-88
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• 2018

Security situations are fundamentally and rapidly changing on the Korean Peninsula. Above all, as North Korea(NK) is heightening its nuclear and missile capabilities, Republic of Korea(ROK) is facing an existential threat. At the same time, as China's economic, diplomatic and military power is quickly rising, the balance of power is shifting and strategic competition between the Unite States(US) and China is accelerating in the Asia-Pacific region. Under the pressure of development of these situations, ROK seems to face allegedly the most serious crisis in its national security since the end of the Korean War. In the current grim geopolitical situation, maritime security may become the most difficult security challenge for ROK in the years to come. The purpose of this paper is to compare major changes in maritime security affairs of the ROK during last twenty years from 1998 until now(2018). 1998 was when this journal 『Strategy 21』 was published for the first time by the Korea Institute for Maritime Strategy. Then, this paper tries to identify challenges and risks with which this country has to deal for its survival and prosperity, and to propose some recommendations for the government, the Navy, and the Coast Guard as they are responsible for the maritime security of the country. The recommendations of this paper are as follows: strengthen ROK-US alliance and expand security cooperation with regional powers in support of the maintenance of the current security order in the region; building-up of maritime security capacity in preparation for crisis on the maritime domain with the navy targeting to acquire 'a non-nuclear, balance-of-terror capability, to improve interoperability with the Coast Guard based on 'a national fleet,' and to actively pursue innovation in naval science and technology. Finally, this paper proposes that naval capability the country needs in another twenty years depends on how effectively and rigorously the navy put its utmost efforts towards building 'a strongest navy' today.

• Strategy21
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• 통권36호
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• pp.121-149
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• 2015

This paper will examine some past and current issues concerning the Republic of Korea's national strategy, focusing predominantly upon how the ROK should respond to the urgent maritime-oriented strategy highlighted by the recent developments and achievements of national prosperity achieved during last three decades and identify some of successful cases in East Asia. Some consideration will also be given to more general emergent issues of trends and developments of East Asian countries which might affect to define the ROK's future national strategy in the context of its national grand strategy to enhance national interests and prosperity. ROK is especially dependent upon open Sea Lanes of Communication (SLOC) and its national security emphasizes the sea as the medium of geopolitical and geo-economic development, given the sea known as core geographic option remains that ROK is an important maritime power, ranking the world-level nation in term of GDP, sea-borne trade, container processing capability, shipbuilding capacity and so on. It should be apparent, therefore, that ROK's national strategic development depends upon the relationship between its peninsula geography and its national development based on sea-borne economic growth and its maritime-oriented future national strategy will be the best option to maintain its national development and economic prosperity.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2010년도 한국컴퓨터종합학술대회논문집 Vol.37 No.1(A)
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• pp.293-294
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• 2010

• International Journal of Fluid Machinery and Systems
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• 제2권2호
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• pp.156-164
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• 2009

This paper aims to describe the importance of data, data collection methods, parameters to estimate the potential of wave energy and environmental impacts. The technical and economical status in wave energy conversion is outlined. Power and energy efficiency relationships are discussed. Many different types of wave-energy converters have been detailed. The progress in wave energy conversion in Malaysia is reviewed.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2018년도 공동국제학술발표회
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• pp.194-194
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• 2018

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 공동학술발표회
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• pp.224-224
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• 2017