• 한국초지학회:학술대회논문집
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• 한국초지조사료학회 1999년도 제24회 정기총회 및 프로그램, 제37회 학술발표회 및 특별강연 초록
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• pp.90-91
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• 1999

알팔파(Medicago sative L.)의 질소공급형태에 따른 저장질소의 함량과 재생기간 중 저장 질소의 이용 및 재생활력을 구명하고자 수경재배하에서(NH$_4$)$_2$SO$_4$, KNO$_3$, Urea, Organic-N 및 NH$_4$NO$_3$를 1mM/week로 4주간 공급후 예취하여 건물생산량을 보았으며, 다시 4mM로 40일 동안 각각의 질소 형태로 공급하여 흡수 및 잔여기관내 축적된 질소의 함량을 분석하였고, 저장된 질소에 의한 재생활력을 보기 위해 0.2mM NH$_4$NO$_3$의 형태로 동일하게 공급하였다.(중략)

• 한국초지학회:학술대회논문집
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• 한국초지조사료학회 1999년도 제24회 정기총회 및 프로그램, 제37회 학술발표회 및 특별강연 초록
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• pp.89-90
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• 1999

페레니얼 라이그라스(Lolium perenne L.)의 질소공급형태에 따른 저장질소의 함량과 재생기간 중 저장질소의 이용 및 재생활력을 구명하고자 수경재배 하였다. (NH$_4$)$_2$SO$_4$, KNO$_3$, Urea, Organic-N 및 NH$_4$NO$_3$의 서로 다른 질소형태로 각각 1mM/week을 4주간 공급하여 건물생산량을 보았고, 예취 후 각각의 질소 형태로 4mM/40days동안 공급하여 흡수된 질소의 함량 및 잔여기관내 축적된 질소의 함량을 관찰하였으며, 예취 후 저장된 질소에 의한 재생활력을 보기 위해 0.2mM NH$_4$NO$_3$의 형태로 동일하게 공급하였다.(중략)

• 한국수소및신에너지학회논문집
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• 제9권1호
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• pp.1-7
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• 1998

Most of today's energy supply is obtained from fossil fuels. Despite of high energy density, higher store efficiency and long mileage, fossil fuels cause environmental pollution and their reserves are limited. In this study pure hydrogen gas and oxygen gas are burned without the emission of pollution. A gas turbine is used to obtain power. Water is injected into a combustor, which prevents overheating and recovers cooling heat. Excessively supplied water is recirculated. With variation of mass flow rate and equivalence ratio, the affection of water injection rate and the temperature of injected water on efficiency and power are experimented. Injected water gets cooling heat, is expanded from liquid to vapor and raises the thermal efficiency. It is enable to determine the rate of water injection, which makes the maximum power. The increase of temperature of water injection raises the efficiency of the system.

• Nuclear Engineering and Technology
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• 제39권6호
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• pp.683-690
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• 2007

Because of increasing concerns regarding global warming and the longevity of oil and gas reserves, the importance of nuclear energy as a major source of sustainable energy is gaining recognition worldwide. To make nuclear energy truly sustainable, it is necessary to ensure not only the sustainability of the fuel supply but also the sustained availability of waste repositories, especially those for high-level radioactive waste (HLW). From this perspective, the effort to maximize the waste loading density in a given repository is important for easing repository capacity problems. In most cases, the loading of a repository is controlled by the decay heat of the emplaced waste. In this paper, a comparison of the decay heat characteristics of HLW is made among the various fuel cycle options. It is suggested that, for a future fast breeder reactor (FBR) cycle, the removal and burning of minor actinides (MA) would significantly reduce the heat load in waste and would allow for a reduction of repository size by half.

• 한국경영과학회지
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• 제25권1호
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• pp.85-92
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• 2000

Channel management is critical in designing a cellular mobile system that offers high capacity and high quality. In this paper, an integrated channel management scheme is proposed, which consists of a dynamic channel allocation scheme and an admission control scheme. The dynamic channel allocation scheme allocates a call request the channel which minimizes the impact on its interfering cell, and consists of two types of channel allocation strategies : nominal channel allocation strategy and non-nominal channel allocation strategy. The admission control scheme named the variable cutoff priority scheme reserves some frequency channels for handoff cells in each cell the number of which varies according to the blocking probability of handoff class in that cell. Computationl tests are performed to evaluate the performance of the proposed scheme in terms of overall blocking probability, defined by the weighted value of the blocking probabilities of new calls and handoff calls. The results show that the proposed scheme yields better performance than other compared schemes.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.19-23
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• 2003

This paper presents a new concept of reactive reserve based contingency constrained optimal power flow (RCCOPF) for voltage stability enhancement. This concept is based on the fact that increase in reactive reserves is effective for enhancement of voltage stability margins of post-contingent states, in this paper, the proposed algorithm is applied to voltage stability margin of interface flow. Interface flow limit, in the open access environment, can be a main drawback. RCCOPF for enhancement of interface flow margin is composed of two modules, modified continuation power flow (MCPF) and optimal power flow (OPF). These modules art recursively perform ed until satisfying the required margin of interface flow in the given voltage stability criteria.

• Journal of international Conference on Electrical Machines and Systems
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• 제2권2호
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• pp.148-153
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• 2013

It is important to improve the efficiencies of motors to overcome problems such as decreasing energy reserves and environmental pollution. Superconductors are promising for developing high-efficiency motors. However, superconducting wires must be kept in critical conditions and the AC loss needs to be minimized. In this paper, a design of a superconducting interior permanent magnet synchronous motor (IPMSM) is proposed that reduces the AC loss. The characteristics of superconducting and normal-conducting IPMSMs are compared. The proposed superconducting IPMSM has a low AC loss and a very high efficiency at low speeds.

• 한국과학교육학회지
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• 제16권4호
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• pp.461-469
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• 1996

The purpose of this study was to assess the attitudes of secondary school students in Korea toward science-technology related issues. A questionnaire was designed in which students were confronted with personal, global, and philosophical levels of arguments, which were composed of three against and three in favor of each eight issues, i.e., use of antibiotics, family planning, transplant of organs, genetic engineering, use of microorganisms. exploitation of the sea, land reclamation from the sea, and nature reserves. Student was requested to rate each argument independently and to vote for or against each issue. It was shown that most of students voted in favor of using technologies except land reclamation from the sea, and that students having more learning experiences on each topic vote more favorably. It is thought that our science education might be effective in increasing awareness and appreciation of benifits of technology, but it is not as effective in developing ambivalence attitudes.

• 한국정보처리학회논문지
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• 제6권10호
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• pp.2790-2796
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• 1999

In video-on-demand systems, the I.O bandwidth of video servers is the critical resource which contributes to increase in latency. Several approaches: bridging, piggybacking are used to reduce the I/O demand on the video server through sharing. Batching delays the requests for the different videos for a batching window so that more requests for the same video arriving during the current batching window may be served using the same stream. In this paper, we propose an adaptive reservation-based batching policy which dynamically reserves video server capacity for popoular videos according to video server loads. The performance of the proposed policy is evaluated through a simulation, and is compared with simple batching and static reservation-based batching policies. As the result, we know that the adaptive reservation-based batching policy more improves service ratio and average waiting time than simple batching and simple reservation-based batching policy more improves service ratio and average waiting time than simple batching and simple reservation-based batching polices.

• 한국정보처리학회논문지
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• 제7권2호
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• pp.454-460
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• 2000

본 논문에서는 네트워크 환경에서의 외부침입에 대한 효율적인 탐지 구조를 제안하였다. 제안된 탐지구조에서는 각기 고유의 기능과 영역을 갖는 다수의 에이젼트들 사이에 블랙보드 구조를 갖는 협조 에이젼트(Coordination Agent)를 두고 Conflict Resolution 기능과 침입여부 확증 기능을 갖도록 함으로서 False Alarm을 감소시키도록 하였다. 시뮬레이션 결과 단순한 시스템 자원의 접근에도 기존 에이전트 방식은 침입이라는 판단을 내릴 수 있는 반면, 블랙보드 시스템은 에이젼트에 대한 적극적인 질의과정을 통해 최종적인 침입의 여부를 판정함으로써 침입 탐지 시스템의 신뢰도를 높일 수 있는 것으로 판단되었다.