• Title/Summary/Keyword: Core affect

Search Result 503, Processing Time 0.032 seconds

Analysis of free surface motions in the hoot Pool of KALIMER (KALIMER 고온풀 자유액면 거동 해석)

  • Kim Seong-O;Eoh Jae-Hyuk;Choi Hoon-Ki
    • Journal of computational fluids engineering
    • /
    • v.7 no.3
    • /
    • pp.44-52
    • /
    • 2002
  • An analytic methodology was developed for free surface motions between liquid metal coolant and cover gas in order to calculate the phenomena of gas entrainment in hot pool surface through IHX EMP and reactor core. The methodology was setup by applying the first order VOF convection model to CFX4 general purpose fluid dynamics analysis code. The methodology was validated by applying it to an experimental apparatus designed for free surface motions of KALIMER reactor. The distributions of free surface calculated by the present methodology were almost coincident with the experimental data. The developed methodology was applied to the KALIMER reactor of full power operating condition. The shapes of the free surface were nearly uniform. From the results, it was found that the altitude of the free surface from the IHX inlet nozzle of KALIMER reactor is high enough not to affect to free surface motions of generating gas bubbles from the turbulent shear flows such as hydraulic jump and water falls.

Fault Current Limiting Characteristics of Separated and Integrated Three-Phase Flux-Lock Type SFCLs

  • Lim, Sung-Hun
    • Journal of Electrical Engineering and Technology
    • /
    • v.2 no.3
    • /
    • pp.289-293
    • /
    • 2007
  • The fault current limiting characteristics of the separated and the integrated three-phase flux-lock type superconducting fault current limiters (SFCLs) were analyzed. The three-phase flux-lock type SFCL consisted of three flux-lock reactors and three $high-T_c$ superconducting (HTSC) elements. In the integrated three-phase flux-lock type SFCL, three flux-lock reactors are connected on the same iron core. On the other hand, three flux-lock reactors of the separated three-phase flux-lock type SFCL are connected on three separated iron cores. The integrated three-phase flux-lock type SFCL showed the different fault current limiting characteristics from the separated three-phase flux-lock type SFCL that the fault phase could affect the sound phase, which resulted in quench of the HTSC element in the sound phase. Through the computer simulation applying numerical analysis for its three-phase equivalent circuit, the fault current limiting characteristics of the separated and the integrated three-phase flux-lock type SFCLs according to the ground fault types were compared.

A Study on the Jangseoksun(張錫純)'s "Sanghanrongang-ui(傷寒論講義)" (장석순(張錫純)의 "상한론강의(傷寒論講義)" 연구)

  • Jang, Woo-Chang
    • Journal of Korean Medical classics
    • /
    • v.22 no.2
    • /
    • pp.349-362
    • /
    • 2009
  • Jangseoksun(張錫純), a noted doctor of China in the early 20th century, has influenced the establishment of Contemporary Chinese Medicine greatly. , which is an accumulation of Jang's lectures and publications, contains the essence of his medical spirit to fuse his theory and experience of Traditional Medicine and the newly imported Western Medicine knowledge of his time. is especially important, presenting the core of Jang's academic theory. In this book he gives full play of his unique experience of treating the Eum(陰, Yin) Deficiency Syndrome which is presented as excess in the upper and deficiency in the lower[上盛下虛]. He also shows the importance of merging theory and practice, the pliability to collaborate the Sanghan(傷寒, Damage from Cold) theory and Onbyeong(溫病, Epidemic Febrile Disease) theory and the study of the blended affect of external and internal pathogens.

  • PDF

A Study on the IT Evaluation Framework in perspective of IT competency of Enterprise (기업 정보화 역량 관점의 정보화 수준 평가체계에 관한 연구)

  • Cha, Jeong-Hun;Lee, Byeong-Yul;Sin, Seon-Do;Im, Chun-Seong
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 2008.10a
    • /
    • pp.487-491
    • /
    • 2008
  • An informatization is recognized as core factors to reinforce business competitiveness such as formation of a new business relation, prior occupation of the strategic superiority and being a step ahead from the purpose to improve only the whole efficiency of enterprise. But existed evaluation framework has focused on the visible aspect of all the conditions to create the input and output. In previous studies, it's hard to know that how IT affect business value creation. Therefore, this study presents the evaluation of IT structure and IT competency as drivers and inhibitors of informatization and suggests new IT evaluation framework which can estimate IT competency. The new IT Evaluation Framework was verified through survey with experts.

  • PDF

NMR characterization of SRG3 SWIRM Domain Mutant Proteins.

  • Koh, Woo-Hyoung;Kim, Min-Tae;Moon, Sun-Jin;Lee, Weon-Tae
    • Journal of the Korean Magnetic Resonance Society
    • /
    • v.13 no.1
    • /
    • pp.56-63
    • /
    • 2009
  • SWIRM domain, a core domain of SRG3 is well conserved in SW13, RSC8, and MOIRA family proteins. To understand structural basis for cellular functions of the SWIRM domain, we have initiated biochemical and structural studies on SWIRM domain and mutants using gelfiltration chromatography, circular dichroism and NMR spectroscopy. The structural properties of the mutant SWIRM domains (K34A and M75A) have been characterized, showing that the structures of both wild-type and mutant proteins are a-helical conformation. The data conclude that mutations at interaction sites of its binding partner protein do not affect its secondary and tertiary structure.

Reduction of Armature Reaction for Moving Coil Linear Oscillatory Actuator (가동코일형 LOA에서의 전기자 반작용 저감법)

  • Jang, S.M.;Jeong, S.S.;Lee, S.H.;Yun, I.K.
    • Proceedings of the KIEE Conference
    • /
    • 2001.07b
    • /
    • pp.580-582
    • /
    • 2001
  • In moving coil LOA, the variation of mover position and the consequent changes of coil flux path affect the coil inductance because of unbalanced magnetic circuit. Furthermore, the armature field shifts and distorts the airgap flux density distribution due to the magnet alone by a certain amount, which cause the unbalanced reciprocating force. In this paper, we propose the reduction method of armature reaction and coil inductance. The proposed LOA has the shorted ring the saturated core, the double coil, and Halbach array.

  • PDF

기술혁신 기업과 R&D 프로젝트 파이낸스 : 지속적 기술혁신을 위한 자금조달의 대안

  • 김영훈;변혜영;이정동
    • Proceedings of the Technology Innovation Conference
    • /
    • 2006.02a
    • /
    • pp.170-186
    • /
    • 2006
  • The guarantee funds for government policy fund, venture capital investment fund, technology guarantee debt are the core parts of the external financing system in the constant technology innovation company. However, the enterpriser's requirement to keep the technology innovation with minimized management intervention and policy maker's hope to advance technology development with clear operation of funds is enough to request for research of the project investment plan to the R&D project. This paper will analyze whether technology innovation company that creates cash flow prefers to the project investment as a financing program or not, and if prefers, what characters of company affect on this preference. The more the company that pursuit the additional R&D activity separated to on-going items becomes over the fixed size, the more prefers the project investment as future external fund-raising. Together with that, this paper suggests that we can apply the plan like special purpose vehicle, SWORD(Stock Warrant Off-Balance sheet R&D) and R&D Limited Partnership as R&D project investment policy, and improve the system itself.

  • PDF

An Experimental Study on Structure of Air-assist Spray with Air Entrainment (공기유입을 고려한 2유체 분무의 구조에 관한 실험적 연구)

  • Chae, H.C.;Kim, D.I.;Oh, S.H.
    • Journal of ILASS-Korea
    • /
    • v.6 no.1
    • /
    • pp.9-17
    • /
    • 2001
  • The effect of air entrainment in twin-fluid spray structure is investigated experimentally by varing the amount of itemizing air. The air entrainment is expected to affect on droplet size and velocity, droplet number density, turbulent kinetic energy and vorticity. PDA(Phase Doppler Anemometer) and PIV(Particle Image Velocimetry) system are used to measure those important factors in analyzing spray structure. The results show that spray structure consists of three distinctive regions ; the atomizing region near nozzle, characterizing strong convective effect, the central core region where droplets are accelerated, and the spray sheath region where droplets are decelerated due to air entrainment. The local air entrainment rate is largest near nozzle, characterizing strong turbulent kinetic energy and vorticity but deceases along axial distance.

  • PDF

Assessing Alternative Renewable Energy Policies in Korea's Electricity Market

  • KIM, HYUNSEOK
    • KDI Journal of Economic Policy
    • /
    • v.41 no.4
    • /
    • pp.67-99
    • /
    • 2019
  • This paper, focusing on the renewable portfolio standard (RPS), evaluates alternative renewable energy policies. We propose a tractable equilibrium model which provides a structural representation of Korea's electricity market, including its energy settlement system and renewable energy certificate (REC) transactions. Arbitrage conditions are used to define the core value of REC prices to identify relevant competitive equilibrium conditions. The model considers R&D investments and learning effects that may affect the development of renewable energy technologies. The model is parameterized to represent the baseline scenario under the currently scheduled RPS reinforcement for a 20% share of renewable generation, and then simulated for alternative scenarios. The result shows that the reinforcement of the RPS leads to higher welfare compared to weakening it as well as repealing it, though there remains room to enhance welfare. It turns out that subsidies are welfare-inferior to the RPS due to financial burdens and that reducing nuclear power generation from the baseline yields lower welfare by worsening environmental externalities.

Optimization of Fuel-cell stack design using CFD-ACE (CFD-ACE를 이용한 연료 전지 냉각판의 최적 설계)

  • 홍민성;김종민
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 2003.10a
    • /
    • pp.14-18
    • /
    • 2003
  • Feul-cell system consists of fuel reformer, stack and energy translator. Among these parts, slack is a core part which produces electricity directly. In order to set a stack module, fabrication of appropriate stack, design of water flow path in stack, and control of coolant are needed. Especially, water or air is used as a coolant to dissipate heat. The different temperature of each electric cells after cooling and the high temperature of the stack affect the performance of the stack, Therefore, it is necessary that the relationship between coolant, healing rate, width of slack, properties of stack, and the shape of water flow path must be understood. For the optimal design, the computational simulation by CFD-ACE has been conducted and the resulting database has been constructed.

  • PDF