• Title/Summary/Keyword: Grid generation

Search Result 1,129, Processing Time 0.029 seconds

Implementation Strategy of Global Framework for Climate Service through Global Initiatives in AgroMeteorology for Agriculture and Food Security Sector (선도적 농림기상 국제협력을 통한 농업과 식량안보분야 전지구기후 서비스체계 구축 전략)

  • Lee, Byong-Lyol;Rossi, Federica;Motha, Raymond;Stefanski, Robert
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.15 no.2
    • /
    • pp.109-117
    • /
    • 2013
  • The Global Framework on Climate Services (GFCS) will guide the development of climate services that link science-based climate information and predictions with climate-risk management and adaptation to climate change. GFCS structure is made up of 5 pillars; Observations/Monitoring (OBS), Research/ Modeling/ Prediction (RES), Climate Services Information System (CSIS) and User Interface Platform (UIP) which are all supplemented with Capacity Development (CD). Corresponding to each GFCS pillar, the Commission for Agricultural Meteorology (CAgM) has been proposing "Global Initiatives in AgroMeteorology" (GIAM) in order to facilitate GFCS implementation scheme from the perspective of AgroMeteorology - Global AgroMeteorological Outlook System (GAMOS) for OBS, Global AgroMeteorological Pilot Projects (GAMPP) for RES, Global Federation of AgroMeteorological Society (GFAMS) for UIP/RES, WAMIS next phase for CSIS/UIP, and Global Centers of Research and Excellence in AgroMeteorology (GCREAM) for CD, through which next generation experts will be brought up as virtuous cycle for human resource procurements. The World AgroMeteorological Information Service (WAMIS) is a dedicated web server in which agrometeorological bulletins and advisories from members are placed. CAgM is about to extend its service into a Grid portal to share computer resources, information and human resources with user communities as a part of GFCS. To facilitate ICT resources sharing, a specialized or dedicated Data Center or Production Center (DCPC) of WMO Information System for WAMIS is under implementation by Korea Meteorological Administration. CAgM will provide land surface information to support LDAS (Land Data Assimilation System) of next generation Earth System as an information provider. The International Society for Agricultural Meteorology (INSAM) is an Internet market place for agrometeorologists. In an effort to strengthen INSAM as UIP for research community in AgroMeteorology, it was proposed by CAgM to establish Global Federation of AgroMeteorological Society (GFAMS). CAgM will try to encourage the next generation agrometeorological experts through Global Center of Excellence in Research and Education in AgroMeteorology (GCREAM) including graduate programmes under the framework of GENRI as a governing hub of Global Initiatives in AgroMeteorology (GIAM of CAgM). It would be coordinated under the framework of GENRI as a governing hub for all global initiatives such as GFAMS, GAMPP, GAPON including WAMIS II, primarily targeting on GFCS implementations.

Construction of Basin Scale Climate Change Scenarios by the Transfer Function and Stochastic Weather Generation Models (전이함수모형과 일기 발생모형을 이용한 유역규모 기후변화시나리오의 작성)

  • Kim, Byung-Sik;Seoh, Byung-Ha;Kim, Nam-Won
    • Journal of Korea Water Resources Association
    • /
    • v.36 no.3 s.134
    • /
    • pp.345-363
    • /
    • 2003
  • From the General Circulation Models(GCMs), it is known that the increases of concentrations of greenhouse gases will have significant implications for climate change in global and regional scales. The GCM has an uncertainty in analyzing the meteorologic processes at individual sites and so the 'downscaling' techniques are used to bridge the spatial and temporal resolution gaps between what, at present, climate modellers can provide and what impact assessors require. This paper describes a method for assessing local climate change impacts using a robust statistical downscaling technique. The method facilitates the rapid development of multiple, low-cost, single-site scenarios of daily surface weather variables under current and future regional climate forcing. The construction of climate change scenarios based on spatial regression(transfer function) downscaling and on the use of a local stochastic weather generator is described. Regression downscaling translates the GCM grid-box predictions with coarse resolution of climate change to site-specific values and the values were then used to perturb the parameters of the stochastic weather generator in order to simulate site-specific daily weather values. In this study, the global climate change scenarios are constructed using the YONU GCM control run and transient experiments.

A Study on the Editorial Design of Magazine, Its New Concept & Advancement (디자인 전문지 <에미그레(Emigre)> 편집디자인의 혁신과 진보)

  • 이옥수
    • Archives of design research
    • /
    • v.13 no.4
    • /
    • pp.163-174
    • /
    • 2000
  • issued in the U.S is a magazine specialized in graphic design, which has a totally different style from commercial magazines such as show case. The main motive why Rudy VanderLans, the publisher, first issued this magazine in the early 1980s is his assertion that there is no design paradigm of universial concept in the aspect of viaual communication design. Also, it started from his recognition that a medium for letting a new generation's show their liberal thinking and experimental expressions. This study looks at theologies and assertions on new graphic concept, which is called the New Wave of graphic design by classifying the plans of into form and contents, and analyzes its specialty in design. Also, this study examines the overall trends of non-Grid editorial design since the modern style. By doing so, I could have a general look at the progressive traits and their futuristic directions that become to have a shorter life cycle with the advent of the 21st century's information era, high-tech media and the change of production environment by digital technology.

  • PDF

Generation of Charged Clusters and their Deposition in Polycrystalline Silicon Hot-Wire Chemical Vapor Deposition (열선 CVD 증착 다결정 실리콘에서 전하를 띈 클러스터의 생성 및 증착)

  • Lee, Jae-Ik;Kim, Jin-Yong;Kim, Do-Hyeon;Hwang, Nong-Moon
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2005.11a
    • /
    • pp.561-566
    • /
    • 2005
  • Polycrystalline silicon films were deposited using hot wire CVD (HWCVD). The deposition of silicon thin films was approached by the theory of charged clusters (TCC). The TCC states that thin films grow by self-assembly of charged clusters or nanoparticles that have nucleated in the gas phase during the normal thin film process. Negatively charged clusters of a few nanometer in size were captured on a transmission electron microscopy (TEM) grid and observed by TEM. The negatively charged clusters are believed to have been generated by ion-induced nucleation on negative ions, which are produced by negative surface ionization on a tungsten hot wire. The electric current on the substrate carried by the negatively charged clusters during deposition was measured to be approximately $-2{\mu}A/cm^2$. Silicon thin films were deposited at different $SiH_4$ and $H_2$ gas mixtures and filament temperatures. The crystalline volume fraction, grain size and the growth rate of the films were measured by Raman spectroscopy, X-ray diffraction and scanning electron microscopy. The deposit ion behavior of the si1icon thin films was related to properties of the charged clusters, which were in turn controlled by the process conditions. In order to verify the effect of the charged clusters on the growth behavior, three different electric biases of -200 V, 0 V and +25 V were applied to the substrate during the process, The deposition rate at an applied bias of +25 V was greater than that at 0 V and -200 V, which means that the si1icon film deposition was the result of the deposit ion of charged clusters generated in the gas phase. The working pressures had a large effect on the growth rate dependency on the bias appled to the substrate, which indicates that pressure affects the charging ratio of neutral to negatively charged clusters. These results suggest that polycrystalline silicon thin films with high crystalline volume fraction and large grain size can be produced by control1ing the behavior of the charged clusters generated in the gas phase of a normal HWCVD reactor.

  • PDF

Probabilistic Reliability Based HVDC Expansion Planning of Power System Including Wind Turbine Generators (풍력발전기를 포함하는 전력계통에서의 신뢰도 기반 HVDC 확충계획)

  • Oh, Ungjin;Lee, Yeonchan;Choi, Jaeseok;Yoon, Yongbeum;Kim, Chan-Ki;Lim, Jintaek
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.67 no.1
    • /
    • pp.8-15
    • /
    • 2018
  • New methodology for probabilistic reliability based grid expansion planning of HVDC in power system including Wind Turbine Generators(WTG) is developed in this paper. This problem is focused on scenario based optimal selection technique to decide best connection bus of new transmission lines of HVDC in view point of adequacy reliability in power system including WTG. This requires two kinds of modeling and simulation for reliability evaluation. One is how is reliability evaluation model and simulation of WTG. Another is to develop a failure model of HVDC. First, reliability evaluation of power system including WTG needs multi-state simulation methodology because of intermittent characteristics of wind speed and nonlinear generation curve of WTG. Reliability methodology of power system including WTG has already been developed with considering multi-state simulation over the years in the world. The multi-state model already developed by authors is used for WTG reliability simulation in this study. Second, the power system including HVDC includes AC/DC converter and DC/AC inverter substation. The substation is composed of a lot of thyristor devices, in which devices have possibility of failure occurrence in potential. Failure model of AC/DC converter and DC/AC inverter substation in order to simulate HVDC reliability is newly proposed in this paper. Furthermore, this problem should be formulated in hierarchical level II(HLII) reliability evaluation because of best bus choice problem for connecting new HVDC and transmission lines consideration. HLII reliability simulation technique is not simple but difficult and complex. CmRel program, which is adequacy reliability evaluation program developed by authors, is extended and developed for this study. Using proposed method, new HVDC connected bus point is able to be decided at best reliability level successfully. Methodology proposed in this paper is applied to small sized model power system.

Wind load analysis of Structure for Folding Solar Power System (접이식 태양광 발전 구조물의 풍하중해석)

  • Son, Chang-Woo;Kim, Tae-Kyun;Seo, Tae-Il
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.8
    • /
    • pp.1-7
    • /
    • 2018
  • A folding solar power system is a stand-alone system and is a structure with solar panels attached. It consists of supporting parts and folding parts for ease of movement. While the efficiency of solar panels is also important to produce electricity by maximizing the power efficiency of solar panels, the most important thing is structure stability. The folding solar power structure intended to be developed in this study is a collapsible structure that is easy to move and install into systems that can produce electricity from grid to independent. Since these structures are installed outdoors, wind loads, snow cover, etc. In this paper, the wind loads most affected by the folding solar power generation structure were obtained using the MeshFree Finite Element Method. MeshFree is a program that makes it easier for users to interpret by simplifying the mesh tasks required by an existing analysis. The analysis showed that the greater the angle of inclination of the wind to the ground, the greater the wind load. In addition, reliability was ensured by wind load testing.

A Study on Output Enhancement Method of PV Array Using Electrical Circuit Reconfiguration Algorithm (전기적 회로절체 알고리즘에 의한 태양광 어레이의 출력향상 방안에 관한 연구)

  • Kim, Byung-Mok;Lee, Hu-Dong;Tae, Dong-Hyun;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.21 no.8
    • /
    • pp.9-17
    • /
    • 2020
  • Recently, RES (renewable energy source) projects have been spreading all over the world as an alternative to solve the shortage of energy and environmental problems caused by fossil fuel consumption. The Korean government also supported the policy and demonstration project to increase the proportion of renewable energy to 63.8[GW] until 2030, which is 20[%] of the total power generation. On the other hand, output loss of a PV array can occur when the surrounding high-rise buildings and trees shade a PV array. Therefore, this paper proposes an algorithm to improve the output loss of a PV array, which electrically changes a circuit configuration of PV modules by wiring and switching devices. Furthermore, this study modeled a PV system based on PSIM S/W, which was composed of a PV array, a circuit configuration device, and a grid-connected inverter. From the simulations results with the modeling and test device, the existing method showed no output when 50% of the shade occurs in PV modules. In contrast, the proposed method could produce the output because the voltage in the PV module could be restored to 246[V], and the operation efficiency of the PV system could be improved by the operation algorithm of the circuit configuration device.

Numerical Study on the Performance Assessment for Defrost and De-Icing Modes (승용차의 제상 및 성에 제거 성능 평가를 위한 수치해석적 연구)

  • Kim, Yoon-Kee;Yang, Jang-Sik;Kim, Kyung-Chun;Ji, Ho-Seong
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.35 no.2
    • /
    • pp.161-168
    • /
    • 2011
  • The heating, ventilating, air conditioning (HVAC) system is a very important part of an automotive vehicle: it controls the microclimate inside the passenger's compartment and removes the frost or mist that is produced in cold/rainy weather. In this study, the numerical analysis of the defrost duct in an HVAC system and the de-icing pattern is carried out using commercial CFX-code. The mass flow distribution and flow structure at the outlet of the defrost duct satisfied the duct design specification. For analyzing the de-icing pattern, additional grid generation of solid domain of ice and glass is pre-defined for conductive heat transfer. The flow structure near the windshield, streakline, and temperature fields clearly indicate that the de-icing capacity of the given defrost duct configuration is excellent and that it can be operated in a stable manner. In this paper, the unsteady changes in temperature, water volume fraction, and static enthalpy at four monitoring points are discussed.

Forecast study for active factor of V2B(Vehicle to Building) operation zero energy building using monte carlo method (몬테카를로방법을 이용한 V2B(Vehicle to Building) 운용 제로에너지빌딩의 액티브 요소 예측 연구)

  • Kim, Youngil;Kim, Insoo
    • Journal of Energy Engineering
    • /
    • v.26 no.4
    • /
    • pp.29-34
    • /
    • 2017
  • Factors of Zero-Energy Building are divided into active and passive factor. Passive factor means insulation, heat bridge of building like insulation, windows and doors, awning, outside etc. and active factor means energy output and efficiency coefficient. Energy output of active factor is achieved by new generating energy. This study anticipated how many effects will be produced when not new generating energy but Vehicle to Building; V2B, bi-directional charging and discharging technology, is applied to Zero-Energy Building. In new generating energy, power generation will be anticipated by geography and climate, but in V2B, several input variable like user's discharging intention and number of usable charger etc. should be considered. We can check how much V2B contribute to the Zero-Energy Building by anticipated results, and that results should be anticipated by using probabilitic method because there is few statistical data. This study anticipate change of charging and discharging pattern, based by Demand Response slot, by using monte carlo method among the probabilitic methods.

Effect Analysis for Frequency Recovery of 524 MW Energy Storage System for Frequency Regulation by Simulator

  • Lim, Geon-Pyo;Choi, Yo-Han;Park, Chan-Wook;Kim, Soo-Yeol;Chang, Byung-Hoon;Labios, Remund
    • KEPCO Journal on Electric Power and Energy
    • /
    • v.2 no.2
    • /
    • pp.227-232
    • /
    • 2016
  • To test the effectiveness of using an energy storage system for frequency regulation, the Energy New Business Laboratory at KEPCO Research Institute installed a 4 MW energy storage system (ESS) demonstration facility at the Jocheon Substation on Jeju Island. And after the successful completion of demonstration operations, a total of 52 MW ESS for frequency regulation was installed in Seo-Anseong (28 MW, governor-free control) and in Shin-Yongin (24 MW, automatic generation control). The control system used in these two sites was based on the control system developed for the 4 MW ESS demonstration facility. KEPCO recently finished the construction of 184 MW ESS for frequency regulation in 8 locations, (e.g. Shin-Gimjae substation, Shin-Gaeryong substation, etc.) and they are currently being tested for automatic operation. KEPCO plans to construct additional ESS facilities (up to a total of about 500 MW for frequency regulation by 2017), thus, various operational tests would first have to be conducted. The high-speed characteristic of ESS can negatively impact the power system in case the 500 MW ESS is not properly operated. At this stage we need to verify how effectively the 500 MW ESS can regulate frequency. In this paper, the effect of using ESS for frequency regulation on the power system of Korea was studied. Simulations were conducted to determine the effect of using a 524 MW ESS for frequency regulation. Models of the power grid and the ESS were developed to verify the performance of the operation system and its control system. When a high capacity power plant is tripped, a 24 MW ESS supplies power automatically and 4 units of 125MW ESS supply power manually. This study only focuses on transient state analysis. It was verified that 500 MW ESS can regulate system frequency faster and more effectively than conventional power plants. Also, it was verified that time-delayed high speed operations of multiple ESS facilities do not negatively impact power system operations. It is recommended that further testing be conducted for a fleet of multiple ESSs with different capacities distributed over multiple substations (e.g. 16, 24, 28, and 48 MW ESS distributed across 20 substations) because each ESS measures frequency individually. The operation of one ESS facility will differ from the other ESSs within the fleet, and may negatively impact the performance of the others. The following are also recommended: (a) studies wherein all ESSs should be operated in automatic mode; (b) studies on the improvement of individual ESS control; and (c) studies on the reapportionment of all ESS energies within the fleet.