• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
• /
• pp.698-702
• /
• 2001

In this paper, to solve the defect of stand-alone type power system in a remote area, a hybrid power system with photovoltaic/wind/diesel generators is proposed. A hybrid power system has a power-balanced controller to equilibrate generation power with a given load demand and which is composed of common DC power system. To execute a power-balanced control, a hybrid power system is assumed that all of power generators have the characteristics of an equivalent current-source and load sharing control technique must be needed at the same time. So this paper describes the algorithm of interactive technique for design of a hybrid power system.

• 한국진공학회지
• /
• 제14권2호
• /
• pp.69-77
• /
• 2005

중성입자빔 가열장치의 이온원과 빔라인 부품들을 개발하고 시험하기 위해 제작한 부피 $60m^3$의 시험설비에는 특성 비교를 위해 몇 가지 다른 방식으로 제작된 대용량 크라이오 흡착펌프를 장착하여 사용하고 있다. 크라이오 펌프의 활성탄 패널을 냉각시키면서 수소를 적절한 간격으로 도입하여 수소 분압을 측정하고 그 시간적인 변화를 통해 온도에 따른 수소흡착과 방출특성을 분석해 보았으며 관련 파라미터 사이의 상호 영향에 대해 알아보기 위해 시뮬레이션을 수행했다.

• 대한기계학회논문집A
• /
• 제25권1호
• /
• pp.127-134
• /
• 2001

Wire ropes are widely used in cable car, suspension bridge and elevator, etc. and composed of single or multi-layer strands. It is difficult to find out the characteristics of a strand or wire rope because of complicated geometry and contact condition. In this study, the axial stiffness is evaluated using finite element method and reliable finite element analysis model is presented, taking into consideration the convergence on the length. The axial stiffness predictive equation of a strand is developed using analysis of variance, which can be applicable for characterizing the relationship between load and displacement when the strand configuration is determined.

• 한국정밀공학회지
• /
• 제12권7호
• /
• pp.114-122
• /
• 1995

A digital preview controller is designed for tandem cold mills to achieve a more improvement of the thickness accuracy. Simultaneously a blocked noninteracting controller is synthesized for rejecting the interactive effects among adjacent stands and for controlling independently each roll stand of tandem cold mills. The performance effects and characteristics of the suggested roll contol system are discussed in the practical viewpoint. The simulaltion results show that the thickness accuracy of tandem cold mills can be largely improved by the blocked noninteracting and digital preview controller.

• 한국조명전기설비학회:학술대회논문집
• /
• 한국조명전기설비학회 2009년도 추계학술대회 논문집
• /
• pp.291-295
• /
• 2009

Economic and environmental concerns over fossil fuels encourage the development of photovoltaic(PV) energy systems. Due to the intermittent nature of solar energy. energy storage is needed in a stand-alone PV system for the purpose of ensuring continuous power flow. Grid-connected PV system that supply power in a critical load demand require to curb power fluctuation. In this case. SCB is a effectiveness in controlling power variation due to intrinsic PV system. We propose the Matlab/Simulink dynamic model and power flow characteristics of a hybrid energy system with PV and SCB.

• 전력전자학회논문지
• /
• 제5권1호
• /
• pp.19-25
• /
• 2000

본 논문은 배터리 충방전 제어기를 가지는 독립형 태양광·풍력 복합발전시스템에 대해서 기술한다. 복합발전시스템의 주요 전력원은 일반적으로 태양전지 어레이, 풍력발전, 배터리로 구성된다. 태양광·풍력 복합발전시스템은 기상조건의 상호 보완성 때문에 풍력 또는 태양광을 단독으로 이용하는 것에 비해서 배터리 수요를 줄일 수 있으며, 자연에너지의 활용도를 높이는 장점이 있다. 제안된 복합발전시스템은 충방전 제어기가 포함되어 있어 태양전지 어레이의 최대출력에서 동작할 수 있도록 순시치 제어기로 설계하였다. 본 논문에서는 실험을 통하여 시스템의 동작특성을 검증하였다.

• 전기학회논문지P
• /
• 제60권2호
• /
• pp.53-55
• /
• 2011

The printed wide band monopole antenna having characteristics of dipole by modified coplanar wave guide(CPW) ground plane is presented. We are called a slot-arm printed monopole antenna and investigated the effect of the surface currents of the radiator on ground plane. The proposed antenna is treated as two asymmetric dipoles with the included angle of $90^{\circ}$ degrees which lie along Z-direction symmetrically. It is observed that the effect of the surface currents on the radiation patterns is similar to that of the corresponding dipole. The length and width of the ground plane correspond the radius and length of the dipole respectively. This approach is also valid to general printed monopole antennas. The simulation impedance bandwidth of the proposed antenna the range of 2.4 to 4.6 [GHz] for a voltage stand wave ratio (VSWR)${\leq}$2 and got pick gain of 6 [dBi]. So the proposed antenna is satisfied the requirement of the industry science medical (ISM) band operation.

• 한국실내디자인학회논문집
• /
• 제14권6호
• /
• pp.86-94
• /
• 2005

The recognition of emotionality becomes so important that it is called' emotional consumption society'. Emotional design, which is mostly concern about user's consensus & experiences and in the space, is appeared on commercial place. Emotional design is understanded from a Interactive point of view, human and interior-space. The purpose of this study is to examine the emotional design by analysis of multiple-commercial-functioned shopping places. Specially, the most recently remarkale Jerde partnership's shopping space in Japan. Jerde partnership' project theme is creative experience by making place and experience design. Though, they weren't claim to stand for emotional design, but presented an emotional element in the shopping mall works.

• The Korean Journal of Ecology
• /
• 제19권6호
• /
• pp.499-506
• /
• 1996

Forest stand development in Kwangnung Experimental Forest, Korea, was simulated with a forest succession gap model of the JABOWA/FORET type, in order to predict climax species and characterime the trend of community structure along the succession. The model runs for a period or 1, 000 yr and is based on the averaged successional characteristics of 50 forest plote with an individual size or 1/12 ha gap consisted of the 15 major tree species. The total bimass and leafarea index have arrived at a steady state since about 200 yr and these values are smaller than that or field survey. Carpinus cordata, C. laxiflora, Quercus mongolica and Q. serrata were epected to be climax species that represent about 86% or total biomass in later stage and these results coincided with the previous succession studies from field survey in the area.

• 천문학회보
• /
• 제39권2호
• /
• pp.119.2-119.2
• /
• 2014

Many astrophysical phenomena involve processes of magnetohydrodynamics (MHD) and relativistic magnetohydrodynamics (RMHD). A number of numerical schemes have been developed to solve the equations of ideal MHD and RMHD. Recent codes are based on upwind schemes which solve hyperbolic systems of equations following the characteristics of the systems. Upwind schemes stand out by their robustness, clarity of the underlying physical model, and ability of achieving high resolution. We present MHD and RMHD codes based on the total variation diminishing (TVD) and weighted essentially non-oscillatory (WENO) schemes, which are second and higher order accurate extensions of upwind schemes. We demonstrate the ability and limitation of codes based on upwind schemes through a series of tests.